TECHNICAL FIELD
[001] The embodiments herein generally relate to power transmission unit in vehicles and more particularly, to a locking arrangement in a power transmission unit of a vehicle and a method, which restricts the movement of a gear shift mechanism (gear shift lever and/or 5 speed shift lever) from a neutral gear position towards a reverse gear position thereby restricting engagement of a reverse gear when a range shift mechanism (range lever and/or range shift lever) is in a high range position, and also restricts the movement of the range shift mechanism (range lever and/or range shift lever) from a neutral range position towards the high 10 range position when the reverse gear is in engaged position (gear shift mechanism is in the reverse gear position).
BACKGROUND
[002] Generally, a power transmission unit of a vehicle is used for 15 transmitting power from an engine or an electric motor to the wheels of the vehicle for propelling the vehicle, and for increasing and decreasing the speed of the vehicle. In vehicles such as tractors or other similar vehicles, the power transmission unit comprises a gear shift lever, a range lever, a plurality of gears and may include other standard components as present in 20 a standard power transmission unit. The gear shift lever is operatively connected to at least one of a first gear, a second gear, a third gear, a fourth
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gear and a reverse gear. The range lever is operatively connected to at least one of a low range gear, a medium range gear and a high range dog clutch (high range dog teeth), where the high range dog teeth is integrated with an output shaft of the power transmission unit. The output speed of the first gear is based on the engagement of at least one of the low range gear, the 5 medium range gear and the high range dog clutch. Hence, the first gear has three different output speeds based on the position of the range lever. Similarly the second gear, the third gear, the fourth gear and the reverse gear has three different output speeds based on the position of the range lever. Therefore, the vehicle is provided with twelve forward speeds and 10 three reverse speeds. There are two possible ways to obtain reverse high gear. One way of obtaining the reverse high gear is to engage the range lever adapted to be shifted from a neutral range position to a high range position thereby facilitating engagement of the high range dog clutch (high range) and thereafter, engaging the gear shift lever adapted to be shifted 15 from a neutral gear position to a reverse gear position thereby facilitating engagement of the reverse gear. Other way of obtaining the reverse high gear is to engage the gear shift lever adapted to be shifted from the neutral gear position to the reverse gear position thereby facilitating engagement of the reverse gear and thereafter, engaging the range lever adapted to be 20 shifted from the neutral range position to the high range position thereby facilitating engagement of the high range dog clutch (high range). The
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engagement of the gear shift lever adapted to be shifted from the neutral gear position to the reverse gear position after the engagement of range lever adapted to be shifted from the neutral range position to the high range position, or vice-versa is undesirable to the operator (user) driving the vehicle when the vehicle is operated at no load condition. Further, in heavy 5 haulage application, the engine of the vehicle stalls when the vehicle is operated in reverse gear with the range lever in high range position (high range dog clutch in engaged position). Therefore, it is difficult to control the vehicle when the vehicle is operated in reverse gear with the range lever in high range position (high range dog clutch in engaged position). Hence, 10 the engagement of reverse gear (gear shift lever is in the reverse gear position) after the engagement of range lever adapted to be shifted to high range position (high range dog clutch in engaged position) or the engagement of range lever adapted to be shifted to high range position (high range dog clutch in engaged position) after the engagement of reverse 15 gear (gear shift lever is in the reverse gear position) is undesirable.
[003] Therefore, there exists a need for a locking arrangement in a power transmission unit of a vehicle and a method, which restricts the movement of a gear shift mechanism (gear shift lever and/or speed shift lever) from a neutral gear position towards a reverse gear position thereby 20 restricting engagement of a reverse gear when a range shift mechanism (range lever and/or range shift lever) is in a high range position, and also
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restricts the movement of the range shift mechanism (range lever and/or range shift lever) from a neutral range position towards the high range position when the reverse gear is in engaged position (gear shift mechanism is in the reverse gear position). Further, there exists a need for a locking arrangement in a power transmission unit of a vehicle and a method, which 5 obviates the aforementioned drawbacks.
OBJECTS
[004] The principal object of an embodiment of this invention is to 10 provide a locking arrangement in a power transmission unit of a vehicle, which restricts the movement of a gear shift mechanism (gear shift lever and/or speed shift lever) from a neutral gear position towards a reverse gear position thereby restricting engagement of a reverse gear when a range shift mechanism (range lever and/or range shift lever) is in a high range position, 15 and also restricts the movement of the range shift mechanism (range lever and/or range shift lever) from a neutral range position towards the high range position when the reverse gear is in engaged position (gear shift mechanism is in the reverse gear position).
[005] Another object of an embodiment of this invention is to 20 provide a method for restricting at least one the movement of a gear shift mechanism (gear shift lever and/or speed shift lever) from a neutral gear position towards a reverse gear position thereby restricting engagement of a reverse gear when a range shift mechanism (range lever and/or range shift
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lever) is in a high range position, and the movement of the range shift mechanism (range lever and/or range shift lever) from a neutral range position towards the high range position when the reverse gear is in engaged position (gear shift mechanism is in the reverse gear position) in a power transmission unit of a vehicle. 5
[006] These and other objects of the embodiments herein will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that the following descriptions, while indicating embodiments and numerous specific details thereof, are given by way of 10 illustration and not of limitation. Many changes and modifications may be made within the scope of the embodiments herein without departing from the spirit thereof, and the embodiments herein include all such modifications.
15
BRIEF DESCRIPTION OF DRAWINGS
[007] The embodiments of the invention are illustrated in the accompanying drawings, throughout which like reference letters indicate corresponding parts in the various figures. The embodiments herein will be better understood from the following description with reference to the 20 drawings, in which:
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[008] FIG. 1 depicts a transparent perspective view of a portion of a power transmission unit of a vehicle, according to an embodiment of the invention as disclosed herein;
[009] FIG. 2 depicts a perspective view of another portion of the power transmission unit, according to an embodiment of the invention as 5 disclosed herein;
[0010] FIG. 3 depicts a perspective view of a first locking element of a locking arrangement in the power transmission unit, according to an embodiment of the invention as disclosed herein;
[0011] FIG. 4 depicts a perspective view of the first locking element 10 and a medium and high range shift fork in assembled condition, according to an embodiment of the invention as disclosed herein;
[0012] FIG. 5 depicts another perspective view of another portion of the power transmission unit, where a portion of the first locking element is immediately disposed above a lever engaging portion of a reverse shifter 15 bush therein to restrict engagement of a reverse driven gear on engagement of a gear shift lever adapted to be shifted towards a reverse gear position when a high range dog clutch is in engaged position, according to an embodiment of the invention as disclosed herein;
[0013] FIG. 6 depicts a partial front view of a portion of the power 20 transmission unit, where the first locking element engages corresponding locking element of a speed shift lever therein to restrict engagement of a
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high range dog clutch on engagement of a range lever adapted to be shifted towards a high range position when the reverse driven gear is in engaged position, according to an embodiment of the invention as disclosed herein;
[0014] FIG. 7 depicts a front view of a portion of the power transmission unit, according to embodiment of the invention as disclosed 5 herein;
[0015] FIG. 8 depicts another front view of the portion of the power transmission unit, according to an embodiment of the invention as disclosed herein;
[0016] FIG. 9a depicts a schematic view of a gear shift pattern of 10 the gear shift lever in the power transmission unit, according to an embodiment of the invention as disclosed herein;
[0017] FIG. 9b depicts a schematic view of a range shift pattern of a the range lever in the power transmission unit, according to an embodiment of the invention as disclosed herein; 15
[0018] FIG. 10 depicts a perspective view of a first locking element of a locking arrangement in a power transmission unit of the vehicle, according to another embodiment of the invention as disclosed herein;
[0019] FIG. 11 depicts a perspective view of a speed shift lever and a second locking element of the locking arrangement in assembled 20 condition, according to another embodiment of the invention as disclosed herein;
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[0020] FIG. 12a depicts a flowchart showing the steps of a method for restricting at least one of the movement of a speed shift lever towards a reverse gear position thereby restricting the engagement of a reverse driven gear when a range shift lever is in a high range position and the movement of the range shift lever towards the high range position when the reverse 5 driven gear is in engaged position in a power transmission unit of a vehicle, according to an embodiment of the invention as disclosed herein; and
[0021] FIG. 12b depicts a flowchart showing the steps of a method for restricting at least one of the movement of a speed shift lever towards a reverse gear position thereby restricting the engagement of a reverse driven 10 gear when a range shift lever is in a high range position and the movement of the range shift lever towards the high range position when the reverse driven gear is in engaged position in a power transmission unit of a vehicle, according to another embodiment of the invention as disclosed herein.
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DETAILED DESCRIPTION
[0022] The embodiments herein and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments that are illustrated in the accompanying drawings and detailed in the following description. Descriptions of well-5 known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples 10 should not be construed as limiting the scope of the embodiments herein.
[0023] The embodiments herein achieve a locking arrangement in a power transmission unit of a vehicle and a method, which restricts the movement of a gear shift mechanism (gear shift lever and/or speed shift lever) from a neutral gear position towards a reverse gear position thereby 15 restricting engagement of a reverse gear when a range shift mechanism (range lever and/or range shift lever) is in a high range position, and also restricts the movement of the range shift mechanism (range lever and/or range shift lever) from a neutral range position towards the high range position when the reverse gear is in engaged position (gear shift mechanism 20 is in the reverse gear position). Referring now to the drawings, and more particularly to FIGS. 1 through 12b, where similar reference characters
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denote corresponding features consistently throughout the figures, there are shown embodiments.
[0024] FIG. 1 depicts a transparent perspective view of a portion of a power transmission unit 10 of a vehicle, according to an embodiment of the invention as disclosed herein. In an embodiment, the power 5 transmission unit 10 (as shown in fig. 1, fig. 2 and fig. 5 to fig. 8) includes a locking arrangement 100 (as shown in fig. 1, fig. 2, fig. 5 and fig. 6), a gear shift mechanism (where the gear shift mechanism can be considered as gear shift lever 12), a speed crossrod link 14, a speed crossrod 16, a speed shift lever 18 (as shown in fig. 1, fig. 2, fig. 5 and fig. 6), a range shift 10 mechanism (where the range shift mechanism can be considered as range lever 20), a range crossrod link 22, a range crossrod 24, a range shift lever 26 (as shown in fig. 1, fig. 2 and fig. 5), a plurality of shifter rods 28 (as shown in fig. 1 and fig. 2), a plurality of shifter bushes 30 (as shown in fig. 2), a plurality of shift forks 32, a plurality of gears 34 (as shown in fig. 7), a 15 plurality of synchronizer units 36 (as shown in fig. 7), a plurality of shifter sleeves 38 (as shown in fig. 7), an input shaft I (as shown in fig. 8), a counter shaft C (as shown in fig. 8), an output shaft O (as shown in fig. 8), a range driving shaft S (as shown in fig. 8), a range driven shaft (not shown) and may include other standard components as present in standard 20 power transmission unit. In an embodiment, the power transmission unit 10 can be considered to be a manual power transmission unit. It is also
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within the scope of the invention to practice/implement the locking arrangement 100 in an automatic power transmission unit or an automated manual power transmission unit or a hydro-static power transmission unit or any other type of power transmission unit incorporating any other type of shifting mechanisms. For the purpose of this description and ease of 5 understanding, the locking arrangement 100 of the power transmission unit 10 is explained herein below with reference to be provided in a tractor. It is also within the scope of the invention to implement/practice the components of the locking arrangement 100 of the power transmission unit 10 in an off road vehicle or any other type of vehicle. 10
[0025] FIG. 3 depicts a perspective view of a first locking element 102 of the locking arrangement 100 in the power transmission unit 10, according to an embodiment of the invention as disclosed herein. In an embodiment, the locking arrangement 100 includes a first locking element 102 and the speed shift lever 18 defining a locking element 18a (as shown 15 in fig. 2 and fig. 5). In an embodiment, the first locking element 102 is used to restrict the movement of the gear shift mechanism (gear shift lever 12 and/or the speed shift lever 18) from a neutral gear position (N represents neutral gear position, as shown in fig. 9a and fig. 7) towards a reverse gear position (R represents reverse gear position, as shown in fig. 20 9a and fig. 7) thereby restricting the engagement of a synchronizer ring (not shown) of a reverse synchronizer unit 36r (as shown in fig. 8) with a
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reverse driven gear 34j (as shown in fig. 8) on engagement of the gear shift lever 12 adapted to be shifted/ moved towards the reverse gear position (R) when a high range dog clutch D (as shown in fig. 8) is in engaged position and the range shift mechanism (range lever 20 and/or the range shift lever 26) is in a high range position (H represents high range position, as shown 5 in fig. 9b and fig. 7), and also restricts the movement of the range shift mechanism (range lever 20 and/or range shift lever 26) from a neural range position (N represents neutral range position, as shown in fig. 9b and fig. 7) towards the high range position (H) thereby restricting the engagement of a medium and high range shifter sleeve 38b (as shown in 8) with the high 10 range dog clutch D (as shown in fig. 8) on engagement of the range lever 20 adapted to be shifted/moved towards the high range position (H) when the reverse driven gear 34j is in engaged position and the gear shift mechanism (gear shift lever 12 and/or the speed shift lever 18) is the reverse gear position (R). The high range dog clutch D can be considered 15 to be a high range dog teeth adapted to be integrated with the output shaft O of the power transmission unit 10. In an embodiment, the first locking element 102 includes a first portion 102a, a second portion 102b, a third portion 102c, a fourth portion 102d, a fifth portion 102e and a sixth portion 102f. The first portion 102a of the first locking element 102 extends along 20 the widthwise direction of the power transmission unit 10. The second portion 102b of the first locking element 102 is extending from the first
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portion 102a and disposed away from the first portion 102a of the first locking element 102. The second portion 102b of the first locking element 102 is removably connected to a medium and high range shift fork 32h (as shown in fig. 2, fig. 4, fig. 5 and fig. 8). It is also within the scope of the invention to provide the first locking element 102 removably connected to a 5 medium and high range shifter rod 28h (as shown in fig. 2). The second portion 102b of the first locking element 102 defines a plurality of openings 102o adapted to receive fasteners (not shown) therein to secure the first locking element 102 to the medium and high range shift fork 32h. It is also within the scope of the invention to connect the second portion 102b of the 10 first locking element 102 to the medium and high range shift fork 32h by any other means. The third portion 102c of the first locking element 102 is transversely extending from the first portion 102a of the first locking element 102. The fourth portion 102d of the first locking element 102 is transversely extending from the third portion 102c of the first locking 15 element 102. The fifth portion 102e of the first locking element 102 is extending from the fourth portion 102d and disposed away from the fourth portion 102d of the first locking element 102. The fifth portion 102e (as shown fig. 5) of the first locking element 102 is immediately disposed above a lever engaging portion L (as shown in fig. 5) of a reverse shifter 20 bush 30r (as shown in fig. 2 and fig. 5) on engagement of the range lever 20 adapted to be shifted from the neutral range position (N) to the high range
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position (H), where the movement of the range lever 20 (range shift mechanism) from the neutral range position (N) to the high range position (H) facilitates engagement of the medium and high range shifter sleeve 38b with the high range dog clutch D and thereafter, corresponding portion of the speed shift lever 18 is adapted to engage the fifth portion 102e of the 5 first locking element 102 to restrict the engagement of corresponding portion 18b of the speed shift lever 18 with the lever engaging portion L of the reverse shifter bush 30r therein to restrict the movement of at least one of the speed shift lever 18, the reverse shifter bush 30r, a reverse shift fork 32r and a synchronizer sleeve of the reverse synchronizer unit 36r towards 10 the reverse gear position (R) thereby restricting the engagement of a synchronizer ring of the reverse synchronizer unit 36r with the reverse driven gear 34j on engagement of the gear shift lever 12 adapted to be shifted from the neutral gear position (N) towards the reverse gear position (R) when the high range dog clutch D is in engaged position, and the range 15 shift lever 26 and the range lever 20 is in the high range position (R), where the engagement of the gear shift lever 12 adapted to be shifted towards the reverse gear position (R) occurs after the engagement of the range lever 20 adapted to be shifted to the high range position (H). The fifth portion 102e (as shown in fig. 6) of the first locking element 102 is adapted to engage 20 corresponding portion 18p of the locking element 18a (as shown in fig. 6) of the speed shift lever 18 therein to restrict the movement of at least one of
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the range shift lever 26, a medium and high range shifter bush 30h, the medium and high range shift fork 32h, and a medium and high range shifter sleeve 38b towards the high range position (H) thereby restricting the engagement of the medium and high range shifter sleeve 38b with the high range dog clutch D on engagement of the range lever 20 adapted to be 5 shifted from the neutral range position (N) towards the high range position (H) when the reverse driven gear 34j is in engaged position, and the speed shift lever 18 and the gear shift lever 12 is in the reverse gear position (R), where the engagement of the range lever 20 adapted to be shifted towards the high range position (H) occurs after the engagement of the gear shift 10 lever 12 adapted to be shifted to the reverse gear position (R). The fifth portion 102e of the first locking element 102 substantially defines a slope shape configuration. It is also within the scope of the invention to provide the fifth portion 102e of the first locking element 102 with at least one protrusion corresponding to the locking element 18a of the speed shift lever 15 18, where the locking element 18a of the speed shift lever 18 can be provided with at least one cavity therein to receive the protrusion of the fifth portion 102e of the first locking element 102 therein to restrict at least one of the engagement of medium and high range shifter sleeve 38b with the high range dog clutch D when the reverse driven gear 34j is in engaged 20 position, and the engagement of synchronizer ring (not shown) of reverse synchronizer unit 36r with reverse driven gear 34j, when the high range dog
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clutch D is in engaged position. Further, it is also within the scope of the invention to provide the fifth portion 102e of the first locking element 102 and the locking element 18a of the speed shift lever 18 with the aforementioned combination thereof or with any other locking means therein to restrict at least one of the engagement of medium and high range 5 shifter sleeve 38b with the high range dog clutch D when the reverse driven gear 34j is in engaged position, and the engagement of synchronizer ring (not shown) of reverse synchronizer unit 36r with reverse driven gear 34j, when the high range dog clutch D is in engaged position. The sixth portion 102f of the first locking element 102 is transversely extending from the first 10 portion 102a and connected to the third portion 102c of the first locking element 102. The sixth portion 102f of the first locking element 102 is adapted to provide stiffness to the third portion 102c of the first locking element 102. The first locking element 102 substantially defines a L-shape configuration. However, it is also within the scope of the invention to 15 provide the first locking element 102 in any other shape and size without otherwise deterring the intended function of the first locking element 102 as can be deduced from the description and corresponding drawings.
[0026] In an embodiment, the gear shift mechanism can be considered to be a gear shift lever 12. It is also within the scope of the 20 invention to consider the gear shift mechanism as any other gear shifting means or buttons operated in conjunction with gear shifting means to
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facilitate engagement of corresponding gears 34 (34f, 34g, 34h, 34i and 34j, as shown in fig. 8). The gear shift lever 12 is engaged/operated (pushed or pulled) by the operator (driver/user) to shift/move the gear shift lever 12 to corresponding gear position (N, 1, 2, 3, 4 and R, as shown in fig. 9a) therein to facilitate engagement of corresponding gear 34 (34f, 34g, 34h, 5 34i and 34j) respectively which are required for various driving conditions of the vehicle. For example, the gear shift lever 12 is adapted to be shifted from the neutral gear position (N) to the reverse gear position (R) therein to facilitate engagement of the reverse driven gear 34j. The gear shift lever 12 is engaged by the operator to shift/move the gear shift lever 12 to at least 10 one of a neutral gear position (N), a first gear position (1 represents first gear position, as shown in fig. 9a), a second gear position (2 represents second gear position, as shown in fig. 9a), a third gear position (3 represents third gear position, as shown in fig. 9a), a fourth gear position (4 represents fourth gear position, as shown in fig. 9a) and a reverse gear 15 position (R) thereby facilitating engagement of corresponding gear 34 (34f, 34g, 34h, 34i and 34j) respectively based on the driving condition of the vehicle. The gear shift lever 12 is connected to the speed crossrod link 14.
[0027] The speed crossrod link 14 is used for connecting the gear shift lever 12 to the speed cross rod 16. The speed crossrod link 14 is 20 adapted to move to the speed crossrod 16 in a pre-defined direction (left or right direction) along x-axis (as shown in fig. 1, where the x-axis is parallel
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or co-axial to a longitudinal axis of the speed crossrod 16) and also moves (turns) the speed crossrod 16 in a predefined direction (clockwise or counter clockwise direction) along x-axis in response to the movement of the gear shift lever 12 along corresponding gear position (N, 1, 2, 3, 4 and R). The speed crossrod link 14 is connected to the gear shift lever 12 and 5 the speed crossrod 16.
[0028] The speed crossrod 16 is used to move the speed shift lever 18 in a pre-defined direction (left or right direction) along x-axis therein to facilitate engagement of corresponding portion 18b of the speed shift lever 18 with the lever engaging portion (not shown) of corresponding shifter 10 bush 30 (30f, 30s and 30r, as shown in fig. 2) and also moving (turning) the speed shift lever 18 in a pre-defined direction (clockwise or counter clockwise direction) along x-axis towards corresponding gear position (N, 1, 2, 3, 4 and R, as shown in fig. 7) therein to move corresponding shifter bush 30 (30f, 30s and 30r) in a predefined direction (forward or backward 15 direction) along y-axis (as shown in fig. 1, where the y-axis is parallel or co-axial to a longitudinal axis of the corresponding shifter rods 28 (28f, 28s and 28r, as shown in fig. 2)) towards corresponding gear position (N, 1, 2, 3, 4 and R, as shown in fig. 7) in response to the movement of the speed crossrod link 14 on engagement of the gear shift lever 12 adapted to be 20 moved/shifted to corresponding gear position (N, 1, 2, 3, 4 and R).
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[0029] The speed shift lever 18 is used for selecting corresponding shifter bush 30 (30f, 30s and 30r) and moving corresponding shifter bush 30 (30f, 30s and 30r) in a predefined direction (forward or backward direction) along y-axis towards corresponding gear position (N, 1, 2, 3, 4 and R, as shown in fig. 7) thereby moving/shifting corresponding shifter 5 rod (28f, 28s and 28r, as shown in fig. 5) in a predefined direction (forward or backward direction) along y-axis in response to at least one of the movement of the speed crossrod 16 in the predefined direction (left or right direction) along x-axis, and movement (turning) of the speed crossrod 16 in the predefined direction (clockwise or counter clockwise direction) along x-10 axis towards corresponding gear position (N, 1, 2, 3, 4 and R). The speed shift lever 18 defines a locking element 18a. The locking element 18a is an integral part of the speed shift lever 18 formed thereof in forging process. It is also within the scope of the invention to provide the locking element 18a as a separate part connected to the speed shift lever 18. The locking 15 element 18a of the speed shift lever 18 defines a portion 18p (as shown in fig. 6) corresponding to the fifth portion 102e of the first locking element 102. The portion 18p of the locking element 18a of the speed shift lever 18 is adapted to be engaged by the fifth portion 102e of the first locking element 102 therein to restrict the movement of at least one of the range 20 shift lever 26, the medium and high range shifter bush 30h, the medium and high range shift fork 32h, and the medium and high range shifter sleeve 38b
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towards the high range position (H) thereby restricting the engagement of the medium and high range shifter sleeve 38b with the high range dog clutch D on engagement of the range lever 20 adapted to be shifted from the neutral range position (N) towards the high range position (H) when the reverse driven gear 34j is in engaged position, and the speed shift lever 18 5 and the gear shift lever 12 is in the reverse gear position (R), where the engagement of the range lever 20 adapted to be shifted towards the high range position (H) occurs after the engagement of the gear shift lever 12 adapted to be shifted to the reverse gear position (R). The portion 18p of the locking element 18a of the speed shift lever 18 substantially defines a 10 slope shape configuration. However, it is also within the scope of the invention to provide any other locking means connected to the speed shift lever 18 at a predefined angle without otherwise deterring the intended function of the locking element 18a of the speed shift lever 18 as can be deduced from the description and corresponding drawings. Furthermore, it 15 is also within the scope of the invention to provide the locking element 18a of the speed shift lever 18 in any other shape and size.
[0030] The range shift mechanism can be considered to be a range lever 20. It is also within the scope of the invention to consider the range shift mechanism as any other gear shifting means or buttons operated in 20 conjunction with range shifting means to facilitate engagement of corresponding gears 34 (34l and 34m, as shown in fig. 8) and high range
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dog clutch D. The range lever 20 is engaged/operated (pushed or pulled) by the operator (driver/user) to shift/move the range lever 20 to corresponding range position (N, L and H, as shown in fig. 9b) therein to facilitate engagement of corresponding gear 34 (34l and 34m) and high range dog clutch D respectively which are required for various driving 5 conditions of the vehicle. For example, the range lever 20 is adapted to be shifted from the neutral range position (N) to the high range position (H) therein to facilitate engagement of the high range dog clutch D. The range lever 20 is engaged by the operator to shift/move the range lever 20 to at least one of a neutral range position (N), a low range gear position (L 10 represents low range position, as shown in fig. 9b), a medium range gear position (M represents medium range position, as shown in fig. 9b) and a high range position (H) therein to facilitate engagement of corresponding gear 34 (34l and 34m) and high range dog clutch D respectively based on the driving condition of the vehicle. The range lever 20 is connected to the 15 range crossrod link 22.
[0031] The range crossrod link 22 is used for connecting the range lever 20 to the range crossrod 24. The range crossrod link 22 is adapted to move to the range crossrod 24 in a pre-defined direction (left or right direction) along x-axis (as shown in fig. 1, where x-axis is parallel or co-20 axial to a longitudinal axis of the range crossrod 24) and also moves (turns) the range crossrod 24 in a pre-defined direction (clockwise or counter
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clockwise direction) along x-axis respectively in response to the movement of the range lever 20 along corresponding range position (N, L, M and H). The range crossrod link 22 is connected to the range lever 20 and the range crossrod 24.
[0032] The range crossrod 24 is used to move the range shift lever 5 26 in a pre-defined direction (left or right direction) along x-axis therein to facilitate engagement of corresponding portion (not shown, can be considered as ball portion) of the range shift lever with the lever engaging portion (not shown) of corresponding shifter bush 30 (30l and 30h, as shown in fig. 2) and also moves (turns) the range shift lever 26 in a pre-10 defined direction (clockwise or counter clockwise direction) along x-axis therein to move corresponding shifter bush 30 (30l and 30h) in a predefined direction (forward or backward direction) along y-axis (as shown in fig. 1, where the y-axis is parallel or co-axial to a longitudinal axis of corresponding shifter rods 28 (28l and 28h, as shown in fig. 2)) towards 15 corresponding range position (N, L and H, as shown in fig. 7) in response to the movement of the range crossrod link 22 on engagement of the range lever 20 adapted to be moved/shifted to corresponding range position (N, L and H).
[0033] The range shift lever 26 is used for selecting corresponding 20 shifter bush (30l and 30h) and also moving/shifting corresponding shifter bush 30 (30l and 30h) in a predefined direction (forward or backward
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direction) along y-axis towards corresponding range position (N, L and H) thereby moving/shifting corresponding shifter rod 28 (28l and 28h, as shown in fig. 5) in a predefined direction (forward or backward direction) along y-axis in response to at least one of the movement of the range crossrod 24 in the predefined direction (left or right direction) along x-axis, 5 and movement (turning) of the range crossrod 24 in the predefined direction (clockwise or counter clockwise direction) along x-axis towards corresponding gear position (N, L and H).
[0034] The plurality of shifter rods 28 (as shown in fig. 1, fig. 2, fig. 5 and fig. 8) include a first shifter rod 28f, a second shifter rod 28s, a 10 reverse shifter rod 28r, a low range shifter rod 28l, and a medium and high range shifter rod 28h. The first shifter rod 28f is used for moving a first shift fork 32f (as shown in fig. 8) and a synchronizer sleeve (not shown) of a first synchronizer unit 36f (as shown in fig. 8) in a direction towards a first driven gear 34f or a second driven gear 34g (as shown in fig. 8) 15 thereby facilitating engagement of corresponding synchronizer ring (not shown) of the first synchronizer unit 36f with the first driven gear 34f or the second driven gear 34g respectively in response to the movement of a first shifter bush 30f (as shown in fig. 2) in the predefined direction (forward or backward direction) along y-axis (where y-axis is parallel or 20 co-axial to a longitudinal axis of the first shifter rod 28f) due to the movement (turning) of the speed shift lever 18 in the predefined direction
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(clockwise or counter clockwise direction) along x-axis towards the first gear position (1, as shown in fig. 7) or the second gear position (2, as shown in fig. 7) respectively. The second shifter rod 28s is used for moving a second shift fork 32s (as shown in fig. 8) and a synchronizer sleeve (not shown) of a second synchronizer unit 36s (as shown in fig. 8) in 5 a direction towards a third driven gear 34h or a fourth driven gear 34i (as shown in fig. 8) thereby facilitating engagement corresponding synchronizer ring (not shown) of the second synchronizer unit 36s with third driven gear 34h or the fourth driven gear 34i respectively in response to the movement of a second shifter bush 30s (as shown in fig. 2) in the 10 predefined direction (forward or backward direction) along y-axis (where y-axis is parallel or co-axial to a longitudinal axis of the second shifter rod 28s) due to the movement (turning) of the speed shift lever 18 in the predefined direction (clockwise or counter clockwise direction) along x-axis towards the third gear position (3, as shown in fig. 7) or the fourth gear 15 position (4, as shown in fig. 7) respectively. The reverse shifter rod 28r is used for moving a reverse shift fork 32r (as shown in fig. 8) and a synchronizer sleeve (not shown) of a reverse synchronizer unit 36r (as shown in fig. 8) in a direction towards a reverse driven gear 34j (as shown in fig. 8) thereby facilitating engagement of corresponding synchronizer 20 ring (not shown) of the reverse synchronizer unit 36r with the reverse driven gear 34j in response to the movement of the reverse shifter bush 30r
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(as shown in fig. 2) in the predefined direction (backward direction) along y-axis (where y-axis is parallel or co-axial to a longitudinal axis of the reverse shifter rod 28r) due to the movement (turning) of the speed shift lever 18 in the predefined direction (counter clockwise direction) along x-axis towards the reverse gear position (R, as shown in fig. 7). The low 5 range shifter rod 28l is used for moving a low range shift fork 32l (as shown in fig. 2, fig. 5 and fig. 8) and a low range shifter sleeve 38a (as shown in fig. 8) in a direction towards a low range driven gear 34l (as shown in fig. 8) thereby facilitating engagement of the low range shifter sleeve 38a with the low range driven gear 34l in response to the movement 10 of a low range shifter bush 30l (as shown in fig. 2) in the predefined direction (backward direction) along y-axis (where y-axis is parallel or co-axial to a longitudinal axis of the low range shifter rod 28l) due to the movement (turning) of the range shift lever 26 in the predefined direction (counter clockwise direction) along x-axis towards the low range position 15 (L, as shown in fig. 7). The medium and high range shifter rod 28h is used for moving a medium and high range shift fork 32h (as shown in fig. 2, fig. 4, fig. 5 and fig. 8) and a medium and high range shifter sleeve 38b (as shown in fig. 8) in a direction towards a medium range driven gear 34m or a high range dog clutch D (as shown in fig. 8) thereby facilitating 20 engagement of medium and high range shifter sleeve 38b with the medium range driven gear 34m or the high range dog clutch D respectively in
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response to the movement of a medium and high range shifter bush 30h (as shown in fig. 2) in the predefined direction (forward or backward direction) along y-axis (where y-axis is parallel or co-axial to a longitudinal axis of the medium and high range shifter rod 28h) due to the movement (turning) of the range shift lever 26 in the predefined direction (clockwise or counter 5 clockwise direction) along x-axis towards the medium range position (M, as shown in fig. 7) or the high range position (H, as shown in fig. 7) respectively.
[0035] The plurality of shifter bushes 30 (as shown in fig. 2) include a first shifter bush 30f, a second shifter bush 30s, a reverse shifter bush 30r, 10 a low range shifter bush 30l, and a medium and high range shifter bush 30h. The first shifter bush 30f is mounted to the first shifter rod 28f. The first shifter bush 30f includes a lever engaging portion (not shown), where the lever engaging portion (not shown) of the first shifter bush 30f can be considered to be a slot or an opening or a cavity. The lever engaging 15 portion (not shown) of the first shifter bush 30f is adapted to be engaged by corresponding portion 18b of the speed shift lever 18 therein to move the first shifter bush 30f towards the first gear position (1, as shown in fig. 7) or the second gear position (2, as shown in fig. 7) thereby moving/shifting the first shifter rod 28f in the predefined direction (forward or backward 20 direction) along y-axis therein to move the first shift fork 32f and the synchronizer sleeve (not shown) of the first synchronizer unit 36f in a
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direction towards the first driven gear 34f or the second driven gear 34g respectively thereby facilitating engagement of corresponding synchronizer ring (not shown) of the first synchronizer unit 36f with the first driven gear 34f or the second driven gear 34g respectively in response to movement (turning) of the speed shift lever 18 in predefined direction (clockwise or 5 counter clockwise direction) along x-axis towards the first gear position (1, as shown in fig. 7) or the second gear position (2, as shown in fig. 7) respectively. The second shifter bush 30s is mounted to the second shifter rod 28s. The second shifter bush 30s includes a lever engaging portion (not shown), where the lever engaging portion (not shown) of the second shifter 10 bush 30s can be considered to be a slot or an opening or a cavity. The lever engaging portion (not shown) of the second shifter bush 30s is adapted to engaged by corresponding portion 18b of the speed shift lever 18 therein to move the second shifter bush 30s towards the third gear position (3, as shown in fig. 3) or the fourth gear position (4, as shown in fig. 7) thereby 15 moving/shifting the second shifter rod 28s in the predefined direction (forward or backward direction) along y-axis therein to move the second shift fork 32s and the synchronizer sleeve (not shown) of the second synchronizer unit 36s in a direction towards the third driven gear 34h or the fourth driven gear 34i respectively thereby facilitating engagement of the 20 synchronizer sleeve (not shown) of the second synchronizer unit 36s with the third driven gear 34h or the fourth driven gear 34i respectively in
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response to the movement (turning) of the speed shift lever 18 in the predefined direction (clockwise or counter clockwise direction) along x-axis towards the third gear position (3, as shown in fig. 7) or the fourth gear position (4, as shown in fig. 7) respectively. The reverse shifter bush 30r is mounted to the reverse shifter rod 28r. The reverse shifter bush 30r 5 includes a lever engaging portion L, where the lever engaging portion L of the reverse shifter bush 30r can be considered to be a slot or an opening or a cavity. The lever engaging portion L of the reverse shifter bush 30r is adapted to be engaged by corresponding portion 18b of the speed shift lever 18 therein to move the reverse shifter bush 30r towards the reverse gear 10 position (R, as shown in fig. 7) thereby moving/shifting the reverse shifter rod 28r in the predefined direction (backward direction) along y-axis therein to move the reverse shift fork 32r and the synchronizer sleeve (not shown) of the reverse synchronizer unit 36r in a direction towards the reverse driven gear 34j thereby facilitating engagement of synchronizer 15 sleeve (not shown) of the reverse synchronizer unit 36r with the reverse driven gear 34j in response to the movement (turning) of the speed shift lever 18 in the predefined direction (counter clockwise direction) along x-axis towards the reverse gear position (R, as shown in fig. 7). The low range shifter bush 30l is mounted to the low range shifter rod 28l. The low 20 range shifter bush 30l includes a lever engaging portion (not shown), where the lever engaging portion (not shown) of the low range shifter bush 30l
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can be considered to be a slot or an opening or a cavity. The lever engaging portion (not shown) of the low range shifter bush 30l is adapted to be engaged by corresponding portion (ball portion) of the range shift lever 26 therein to move the low range shifter bush 30l towards the low range position (L, as shown in fig. 7) thereby moving/shifting the low range 5 shifter rod 28l in the predefined direction (backward direction) along y-axis therein to move the low range shift fork 32l and the low range shifter sleeve 38a in a direction towards the low range driven gear 34l thereby facilitating engagement of the low range shifter sleeve 38a with low range driven gear 34l in response to movement (turning) of the range shift lever 26 in the 10 predefined direction (counter clockwise direction) along x-axis towards the low range position (L, as shown in fig. 7). The medium and high range shifter bush 30h is mounted to the medium and high range shifter rod 28h. The medium and high range shifter bush 30h includes a lever engaging portion Z (as shown in fig. 2), where the lever engaging portion Z of the 15 medium and high range shifter bush 30h can be considered to be a slot or an opening or a cavity. The lever engaging portion Z of the medium and high range shifter bush 30h is adapted to be engaged by corresponding portion (ball portion) of the range shift lever 26 therein to move the medium and high range shifter bush 30h towards the medium range 20 position (M, as shown in fig. 7) or the high range position (H, as shown in fig. 7) thereby moving shifting the medium and high range shifter rod 28h
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in the predefined direction (forward or backward direction) along y-axis therein to move the medium and high range shift fork 32h, and the medium and high range shifter sleeve 38b in a direction towards the medium range driven gear 34m or the high range dog clutch D respectively thereby facilitating engagement of the medium and high range shifter sleeve 38b 5 with the medium range driven gear 34m or high range dog clutch D respectively in response to movement (turning) of the range shift lever 26 in the predefined direction (clockwise direction or counter clockwise direction) along y-axis towards the medium range position (M) or the high range position (H) respectively. 10
[0036] The plurality of shift forks 32 (as shown in fig. 1, fig. 2 and fig. 8) includes a first shift fork 32f, a second shift fork 32s, a reverse shift fork 32r, a low range shift fork 32l, and a medium and high range shift fork 32h. The first shift fork 32f is mounted to the first shifter rod 28f and connected to the synchronizer sleeve (not shown) of the first synchronizer 15 unit 36f. The first shift fork 32f is used to move synchronizer sleeve (not shown) of the first synchronizer unit 36f in the direction towards the first driven gear 34f or the second driven gear 34g thereby facilitating engagement of the synchronizer sleeve (not shown) of the first synchronizer unit 36f with the first driven gear 34f or the second driven 20 gear 34g respectively in response to the movement of the first shifter rod 28f in the predefined direction (forward or backward direction) along y-
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axis due to movement of the speed shift lever 18 and the first shifter bush 30f towards the first gear position (1, as shown in fig. 7) or the second gear position (2, as shown in fig. 7) respectively. The second shift fork 32s is mounted to the second shifter rod 28s and connected to the synchronizer sleeve (not shown) of the second synchronizer unit 36s. The second shift 5 fork 32s is used to move the synchronizer sleeve (not shown) of the second synchronizer unit 36s in the direction towards the third driven gear 34h or the fourth driven gear 34i thereby to facilitating engagement of the synchronizer sleeve (not shown) of the second synchronizer unit 36s with the third driven gear 34h or the fourth driven gear 34i in response to the 10 movement of the second shifter rod 28s in the predefined direction (forward or backward direction) along y-axis due to movement of the speed shift lever 18 and the second shifter bush 30s towards the third gear position (3, as shown in fig. 7) or the fourth gear position (4, as shown in fig. 7) respectively. The reverse shift fork 32r is mounted to the reverse shifter 15 rod 28r and connected to the synchronizer sleeve (not shown) of the reverse synchronizer unit 36r. The reverse shift fork 32r is used to move synchronizer sleeve (not shown) of the reverse synchronizer unit 36r in the direction towards the reverse driven gear 34j thereby facilitating engagement of the synchronizer sleeve (not shown) of the reverse 20 synchronizer unit 36r with the reverse driven gear 34j in response to the movement of the reverse shifter rod 28r in the predefined direction
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(backward direction) along y-axis due to movement of the speed shift lever 18 and the reverse shifter bush 30r towards the reverse gear position (R, as shown in fig. 7). The low range shift fork 32l is connected to the low range shifter rod 28l and connected to the low range shifter sleeve 38a. The low range shift fork 32l is used to move low range shifter sleeve 38a in the 5 direction towards the low range driven gear 34l thereby facilitating engagement of the low range shifter sleeve 38a with the low range driven gear 34l in response to the movement of the low range shifter rod 28l in the predefined direction (backward direction) along y-axis due to movement of the range shift lever 26 and the low range shifter bush 30l towards the low 10 range position (L, as shown in fig. 7). The medium and high range shift fork 32h is mounted to the medium and high range shifter rod 28h, and connected to the medium and high range shifter sleeve 38b. The medium and high range shift fork 32h is used to move medium and high range shifter sleeve 38b in the direction towards the medium range driven gear 15 34m or the high range dog clutch D thereby facilitating engagement of the medium and high range shifter sleeve 38b with the medium range driven gear 34m or the high range dog clutch D respectively in response to the movement of the medium and high range shifter rod 28h in the predefined direction (forward or backward direction) along y-axis due to movement of 20 the range shift lever 26, and the medium and high range shifter bush 30h
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towards the medium range position (M, as shown in fig. 7) or the high range position (H, as shown in fig. 7) respectively.
[0037] The plurality of gears 34 (as shown in fig. 7 and fig. 8) include a first driving gear 34a, a second driving gear 34b, a third driving gear 34c, a fourth driving gear 34d, a reverse driving gear 34e, a first driven 5 gear 34f, a second driven gear 34g, a third driven gear 34h, a fourth driven gear 34i, a reverse driven gear 34j, a low range driving gear (not shown), a medium range driving gear 34k, a low range driven gear 34l and a medium range driven gear 34m. The first driving gear 34a is mounted to the countershaft C of the power transmission unit 10. The second driving gear 10 34b is mounted to the countershaft C of the power transmission unit 10. The third driving gear 34c is mounted to the countershaft C of the power transmission unit 10. The fourth driving gear 34d is mounted to the countershaft of the power transmission unit 10. The reverse driving gear 34e is mounted to the input shaft I of the power transmission unit 10. The 15 first driven gear 34f is mounted to the output shaft O of the power transmission unit 10 and rotatably connected to the first driving gear 34a adapted to be mounted to the countershaft C of the power transmission unit 10. The second driven gear 34g is mounted to the output shaft O of the power transmission unit 10 and rotatably connected to the second driving 20 gear 34b adapted to be mounted to the countershaft C of the power transmission unit 10. The third driven gear 34h is mounted to the output
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shaft O of the power transmission unit 10 and rotatably connected to the third driving gear 34c adapted to be mounted to the countershaft C of the power transmission unit 10. The fourth driven gear 34i is mounted to the output shaft O of the power transmission unit 10 and rotatably connected to the fourth driving gear 34d adapted to be mounted to the countershaft C of 5 the power transmission unit 10. The reverse driven gear 34j is mounted to the output shaft O of the power transmission unit 10 and rotatably connected to the reverse driving gear 34e through a cluster of reverse idler gears (not shown) adapted to be mounted to an idler shaft (not shown) of the power transmission unit 10. The low range driving gear (not shown) is 10 mounted to the range driving shaft S of the power transmission unit 10. The medium range driving gear 34k is mounted to the range driving shaft S of the power transmission unit 10. The low range driven gear 34l is mounted to the range driven shaft (not shown) of the power transmission unit 10 and rotatably connected to the low range driving gear (not shown) 15 through a cluster of low range idler gear (not shown). The medium range driven gear 34m is mounted to the range driven shaft (not shown) of the power transmission unit 10 and rotatably connected to the medium range driving gear 34k adapted to be mounted to the range driving shaft S of the power transmission unit 10. 20
[0038] Each synchronizer unit 36 (36f, 36s and 36r, as shown in fig. 7 and fog. 8) includes a synchronizer sleeve (not shown), a hub (not
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shown), a plurality of synchronizer rings (not shown) and may include other standard components as present in standard synchronizer unit of standard power transmission unit. The plurality of synchronizer units 36 (as shown in fig. 7 and fig. 8) includes a first synchronizer unit 36f, a second synchronizer unit 36s and a reverse synchronizer unit 36r. The first 5 synchronizer unit 36f is mounted to the output shaft O of the power transmission unit 10. The first synchronizer unit 36f is used to facilitate smooth engagement of the first driven gear 34f or the second driven gear 34g in response to the movement of the first shift fork 32f in a direction towards the first driven gear 34f or the second driven gear 34g respectively 10 (first gear position (1) or the second gear position (2) respectively). The second synchronizer unit 32s is mounted to the output shaft O of the power transmission unit 10. The second synchronizer unit 36s is used to facilitate smooth engagement of the third driven gear 34h or the fourth driven gear 34i in response to the movement of the second shift fork 32s towards the 15 third driven gear 34h or the fourth driven gear 34i respectively (third gear position (3) or the fourth gear position (4) respectively). The reverse synchronizer unit 36r is mounted to the output shaft O of the power transmission unit 10. The reverse synchronizer unit 36r is used to facilitate smooth engagement of the reverse driven gear 34j in response to the 20 movement of the reverse shift fork 32r towards the reverse driven gear 34j (reverse gear position, R).
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[0039] The plurality of shifter sleeves 38 (as shown in fig. 7 and fig. 8) includes a low range shifter sleeve 38a, and a medium and high range shifter sleeve 38b. The low range shifter sleeve 38a is used to facilitate engagement of the low range driven gear 34l in response to the movement of the low range shift fork 32l towards the low range driven gear 34l (low 5 range position, L). The low range shifter sleeve 38a defines a plurality of internal teeth (not shown) corresponding to the plurality of external teeth (not shown) of the low range driven gear 34l, where the low range shifter sleeve 38a moves towards the low range driven gear 34l thereby enabling the plurality of internal teeth (not shown) of the low range shifter sleeve 10 38a to engage corresponding external teeth (not shown) of the low range driven gear 34l in response to the movement of the low range shift fork 32l towards the low range driven gear 34l (low range position, L) thereby facilitating engagement of the low range shifter sleeve 38a with the low range driven gear 34l. The medium and high range shifter sleeve 38b is 15 used to facilitate engagement of the medium range driven gear 34m or the high range dog clutch D in response to the movement of the medium and high range shift fork 32h in the direction towards medium range driven gear 34m or the high range dog clutch D (medium range position M or high range position, H) respectively. The medium and high range shifter sleeve 20 38b defines a plurality of first internal teeth (not shown) corresponding to the plurality of external teeth (not shown) of the medium range driven gear
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34m, and a plurality of second internal teeth (not shown) corresponding to the plurality of external teeth (not shown) of the high range dog clutch D. The medium and high range shifter sleeve 38b moves towards the medium range driven gear 34m thereby enabling the plurality of first internal teeth (not shown) of the medium and high range shifter sleeve 38b to engage 5 corresponding external teeth (not shown) of the medium range driven gear 34m in response to the movement of the medium and high range shift fork 32h towards the medium range driven gear 34m (medium range position, M) thereby facilitating engagement of the medium and high range shifter sleeve 38b with the medium range driven gear 34m. The medium and high 10 range shifter sleeve 38b moves towards the high range dog clutch D thereby enabling the plurality of second internal teeth (not shown) to engage corresponding external teeth (not shown) of the high range dog clutch D in response to the movement of the medium and high range shift fork 32h towards high range dog clutch D (high range position, H) thereby 15 facilitating engagement of the medium and high range shifter sleeve 38b with the high range dog clutch D.
[0040] The input shaft I of the power transmission unit 10 is rotatably connected to an engine (not shown) of the vehicle through a clutch unit (not shown) of the vehicle. The counter shaft C of the power 20 transmission unit 10 is rotatably connected to the input shaft I of the power transmission unit 10. The output shaft O of the power transmission unit 10
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is rotatably connected to the counter shaft C of the power transmission unit 10 through gears 34. The output shaft O defines a high range dog clutch D (high range dog teeth), where the high range dog clutch D is adapted to be integrated with the output shaft O. The high range dog clutch D defines a plurality of external teeth (not shown) adapted to be engaged by 5 corresponding plurality of second internal teeth (not shown) of the medium and high range shifter sleeve 38b thereby facilitating engagement of the medium and high range shifter sleeve 38b with the high range dog clutch D on engagement of the range lever 20 adapted to be shifted from the neutral range position (N) to the high range position (H). 10
[0041] FIG. 12a depicts a flowchart showing the steps of a method 200 for restricting at least one of the movement of a speed shift lever 18 towards a reverse gear position (R, as shown in fig. 7) thereby restricting the engagement of a reverse driven gear 34j when a range shift lever 26 is in a high range position (H, as shown in fig. 7), and the movement of the 15 range shift lever 26 towards the high range position (H, as shown in fig. 7) when the reverse driven gear 34j is in engaged position in a power transmission unit 10 of a vehicle, according to an embodiment of the invention as disclosed herein. In an embodiment, the method 200 for restricting at least one of the movement of the speed shift lever 18 towards 20 the reverse gear position (R, as shown in fig. 7) thereby restricting the engagement of the reverse driven gear 34j when the range shift lever 26 is
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in the high range position (H, as shown in fig. 7), and the movement of the range shift lever 26 towards the high range position (H, as shown in fig. 7) when the reverse driven gear 34j is in engaged position in the power transmission unit 10 of the vehicle is as follows, the method 200 comprising, providing a locking arrangement 100 comprising a first locking 5 element 102; and a speed shift lever 18 defining a locking element 18a (step 202); moving the first locking element 102 in a direction towards a reverse shifter bush 30r enables a fifth portion 102e of the first locking element 102 to be disposed immediately above a lever engaging portion L of the reverse shifter bush 30r in response to the movement of the range 10 shift lever 26 from a neutral range position (N, as shown in fig. 7) to the high range position (H, as shown in fig. 7) on engagement of a range lever 20 adapted to be shifted from the neutral range position (N, as shown in fig. 9b) to the high range position (H, as shown in fig. 9b), where the engagement of the range lever 20 from the neutral range position (N, , as 15 shown in fig. 9b) to the high range position (H, as shown in fig. 9b) moves at least one of the range shift lever 26, the reverse shifter bush 30r, the medium and high range shift fork 32h, and a medium and high range shifter sleeve 38b to the high range position (H, as shown in fig. 7) thereby facilitating engagement of the medium and high range shifter sleeve 38b 20 with a high range dog clutch D (step 204); moving the speed shift lever 18 in the direction towards the reverse shifter bush 30r enables corresponding
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portion of the speed shift lever 18 to engage the fifth portion 102e of the first locking element 102 to restrict the engagement of corresponding portion 18b of the speed shift lever 18 with the lever engaging portion L of the reverse shifter bush 30r therein to restrict the movement of at least one of the speed shift lever 18, a reverse shifter bush 30r, a reverse shift fork 5 32r and a synchronizer sleeve of a reverse synchronizer unit 36r towards the reverse gear position (R, as shown in fig. 7) thereby restricting the engagement of a synchronizer ring of the reverse synchronizer unit 36r with the reverse driven gear 34j on engagement of a gear shift lever 12 adapted to be shifted from a neutral gear position (N, as shown in fig. 9a) towards 10 the reverse gear position (R, as shown in fig. 9a) when the high range dog clutch D is in engaged position, and the range shift lever 26 and the range lever 20 is in the high range position (R, as shown in fig. 7 and fig 9b) (step 206); moving the fifth portion 102e of the first locking element 102 away from the lever engaging portion L of the reverse shifter bush 30r in 15 response to the movement of the range shift lever 26 from the high range position (H, as shown in fig. 7) to the neutral range position (N, as shown in fig. 7) on engagement of the range lever 20 adapted to be shifted from the high range position (H, as shown in fig. 9b) to the neutral range position (N, as shown in fig. 9b) (step 208); moving the speed shift lever 18 in the 20 direction towards the reverse shifter bush 30r facilitates engagement of corresponding portion 18b of said speed shift lever 18 with the lever
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engaging portion L of the reverse shifter bush 30r therein to move at least one of said speed shift lever 18, the reverse shifter bush 30r, the reverse shift fork 32r and the synchronizer sleeve of the reverse synchronizer unit 36r to the reverse gear position (R, as shown in fig. 7) thereby facilitating engagement of the synchronizer ring of the reverse synchronizer unit 36r 5 with the reverse driven gear 34j on engagement of the gear shift lever 12 adapted to be shifted from the neutral gear position (N, as shown in fig. 9a) to the reverse gear position (R, as shown in fig. 9a) when the range shift lever 26 and the range lever 20 is in the neutral range position (N, as shown in fig. 7 and fig 9b) (step 210); and moving the first locking element 102 in 10 the direction towards the speed shift lever 18 enables the fifth portion 102e of the first locking element 102 to engage corresponding portion 18p of the locking element 18a of the speed shift lever 18 therein to restrict the movement of at least one of the range shift lever 26, the reverse shifter bush 30r, the medium and high range shift fork 32h, and the medium and high 15 range shifter sleeve 38b to the high range position (H, , as shown in fig. 7) thereby restricting engagement of the medium and high range shifter sleeve 38b with the high range dog clutch D when the reverse driven gear 34j is in engaged position, and the speed shift lever 18 and the gear shift lever 12 is in the reverse gear position (R, as shown in fig. 7 and fig. 9a) (step 212). 20
[0042] The working of the locking arrangement 100 in the power transmission unit 10 in conjunction with the method 200 for restricting at
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least one of the movement of the speed shift lever 18 towards the reverse gear position (R, , as shown in fig. 7) thereby restricting the engagement of the reverse driven gear 34j when the range shift lever 26 is in the high range position (H, as shown in fig. 7), and the movement of the range shift lever 26 towards the high range position (H, as shown in fig. 7) when the 5 reverse driven gear 34j is in engaged position in the power transmission unit 10 of the vehicle is as follows. When the operator (user) engages the range lever 20 adapted to be moved/shifted from the neutral range position (N, as shown in fig. 9b) to the high range position (H, as shown in fig. 9b), the range lever 20 moves the range crossrod link 22 therein to move the 10 range crossrod 24 in a predefined direction (right direction) along x-axis thereby enabling corresponding portion (not shown, can be considered as ball portion) of the range shift lever 26 to engage the lever engaging portion Z (as shown in fig. 2) of the medium and high range shifter bush 30h, and also to move (turn) the range crossrod 24 in a predefined direction 15 (counter-clockwise direction) along x-axis therein to enable corresponding portion (not shown, ball portion) of the range shift lever 26 to move the medium and high range shifter bush 30h to the high range position (H, as shown in fig. 7) thereby moving the medium and high range shifter rod 28h in a predefined direction (backward direction) along y-axis thereby 20 enabling the medium and high range shift fork 32h to move the medium and high range shifter sleeve 38b towards the high range dog clutch D
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thereby facilitating engagement of the medium and high range shifter sleeve 38b with the high range dog clutch D, where the first locking element 102 is adapted to move in a direction towards the reverse shifter bush 30r thereby enabling the fifth portion 102e of the first locking element 102 to be disposed immediately above the lever engaging portion L of the 5 reverse shifter bush 30r when the range shift lever 26 moves to the high range position (H, as shown in fig. 7) on engagement of the range lever 20 adapted to be shifted/moved from the neutral range position (N, as shown in fig. 9b) to the high range position (H, as shown in fig. 9b) thereby facilitating engagement of the medium and high range shifter sleeve 38b 10 with the high range dog clutch D. Thereafter, when the operator engages the gear shift lever 12 adapted to be moved/shifted from the neutral gear position (N, as shown in fig. 9a) towards the reverse gear position (R, as shown in fig. 9a), the gear shift lever 12 moves the speed crossrod link 14 therein to move the speed crossrod 16 in a predefined direction (right 15 direction) along x-axis therein to move the speed shift lever 18 towards the reverse shifter bush 30r thereby enabling corresponding portion of the speed shift lever 18 to engage the fifth portion 102e of the first locking element 102 therein to restrict the engagement of the portion 18b of the speed shift lever 18 with the lever engaging portion L of the reverse shifter 20 bush 30r therein to restrict the movement of at least one of speed shift lever 12, the reverse shifter bush 30r, the reverse shift fork 32r and the
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synchronizer sleeve (not shown) of the reverse synchronizer unit 36r towards the reverse gear position (R, as shown in fig. 7) thereby restricting the engagement of the synchronizer ring (not shown) of the reverse synchronizer unit 36r with the reverse driven gear 34j on engagement of the gear shift lever 12 adapted to be shifted from the neutral gear position 5 (N, as shown in fig. 9a) towards the reverse gear position (R, as shown in fig. 9a) when the range lever 20 and the range shift lever 26 is in the high range position (R, as shown in fig. 9b and fig. 7), and the high range dog clutch D is in engaged position, where the engagement of the gear shift lever 12 adapted to be shifted from the neutral gear position (N, as shown 10 in fig. 9a) towards the reverse gear position (R, as shown in fig. 9a) occurs after the engagement of the range lever 20 adapted to be shifted from the neutral range position (N, as shown in fig. 9b) to the high range position (H, as shown in fig. 9b).
[0043] Now, when the operator engages the gear shift lever 12 15 adapted to moved/shifted from the neutral gear position (N, as shown in fig. 9a) to the reverse gear position (R, as shown in fig. 9b), the gear shift lever 12 moves the speed crossrod link 14 therein to move the speed crossrod 16 in a predefined direction (right direction) along x-axis thereby enabling the portion 18b (ball portion) of the speed shift lever 18 to engage the lever 20 engaging portion L of the reverse shifter bush 30r, and also to move (turn) the speed crossrod 16 in a predefined direction (counter-clockwise
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direction) along x-axis therein to enable the portion 18b of the speed shift lever 18 to move the reverse shifter bush 30r to the reverse gear position (R, as shown in fig. 7) thereby moving the reverse shifter rod 28r in a predefined direction (reverse direction) along y-axis thereby enabling the reverse shift fork 32r to move corresponding synchronizer sleeve (not 5 shown) of the reverse synchronizer unit 36r to move towards the reverse gear position (R, as shown in fig. 7) thereby moving corresponding synchronizer ring (not shown) of the reverse synchronizer unit 36r towards the reverse driven gear 34j thereby facilitating engagement of synchronizer ring (not shown) of the reverse synchronizer unit 36r with the reverse 10 driven gear 34j. Thereafter, when the operator engages the range lever 20 adapted to be moved/shifted from the neutral range position (N, as shown in fig. 9b) towards the high range gear position (H, as shown in fig. 9b), the range lever 20 moves the range crossrod link 22 therein to move the range crossrod 24 in a predefined direction (right direction) along x-axis thereby 15 enabling corresponding portion (not shown, ball portion) of the range shift lever 26 to engage the lever engaging portion Z of the medium and high range shifter bush 30h, and also to move (turn) the range crossrod 24 in a predefined direction (counter-clockwise direction) along x-axis therein to enable corresponding portion (not shown, ball portion) of the range shift 20 lever 26 to move the medium and high range shifter bush 30h towards the high range position (H, as shown in fig. 7) thereby moving the medium and
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high range shifter rod 28h in a predefined direction (backward direction) along y-axis therein to move the first locking element 102 in the direction towards the speed shift lever 18 thereby enabling the fifth portion 102e of the first locking element 102 to engage corresponding portion 18p of the locking element 18a of the speed shift lever 18 therein to restrict the 5 movement of at least one of the range shift lever 26, the reverse shifter bush 30r, the medium and high range shift fork 32h, and the medium and high range shifter sleeve 38b to the high range position (H, as shown in fig. 7) thereby restricting engagement of the medium and high range shifter sleeve 38b with the high range dog clutch D when the reverse driven gear 34j is in 10 engaged position, and the speed shift lever 18 and the gear shift lever 12 is in the reverse gear position (R, as shown in fig. 7 and fig. 9a), where the engagement of the range lever 20 adapted to be shifted from the neutral gear position (N, as shown in fig. 9b) towards the high range position (H, as shown in fig. 9b) occurs after the engagement of the gear shift lever 12 15 adapted to be shifted from the neutral gear position (N, as shown in fig. 9a) to the reverse gear position (R, as shown in fig. 9a).
[0044] FIG. 10 depicts a perspective view of a first locking element 102 of a locking arrangement 100 in a power transmission unit 10 of the vehicle, according to another embodiment of the invention as disclosed 20 herein. In another embodiment, the locking arrangement 100 includes a first locking element 102 (as shown in fig. 10) and a second locking
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element 104 (as shown in fig. 11). In another embodiment, the first locking element 102 is used to restrict the movement of the gear shift mechanism (gear shift lever 12 and/or the speed shift lever 18) from a neutral gear position (N, as shown in fig. 9a and fig. 7) towards a reverse gear position (R, as shown in fig. 9a and fig. 7) thereby restricting the engagement of a 5 synchronizer ring (not shown) of a reverse synchronizer unit 36r (as shown in fig. 8) with a reverse driven gear 34j (as shown in fig. 8) on engagement of the gear shift lever 12 adapted to be shifted/ moved towards the reverse gear position (R) when a high range dog clutch D (as shown in fig. 8) is in engaged position and the range shift mechanism (range lever 20 and/or the 10 range shift lever 26) is in a high range position (H, as shown in fig. 9b and fig. 7), and also restricts the movement of the range shift mechanism (range lever 20 and/or range shift lever 26) from a neural range position (N, as shown in fig. 9b and fig. 7) towards the high range position (H) thereby restricting the engagement of a medium and high range shifter sleeve 38b 15 (as shown in 8) with the high range dog clutch D (as shown in fig. 8) on engagement of the range lever 20 adapted to be shifted/moved towards the high range position (H) when the reverse driven gear 34j is in engaged position and the gear shift mechanism (gear shift lever 12 and/or the speed shift lever 18) is the reverse gear position (R). The high range dog clutch D 20 can be considered to be a high range dog teeth adapted to be integrated with the output shaft O of the power transmission unit 10. In another
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embodiment, the first locking element 102 includes a first portion 102a, a second portion 102b, a third portion 102c, a fourth portion 102d and a fifth portion 102e. The first portion 102a of the first locking element 102 extends along the widthwise direction of the power transmission unit 10. The second portion 102b of the first locking element 102 is transversely 5 extending from the first portion 102a and thereafter extending parallel to the first portion 102a and disposed away from the first portion 102a. The second portion 102b of the first locking element 102 is removably connected to the medium and high range shift fork 32h. It is also within the scope of the invention to connect the second portion 102b of the first 10 locking element 102 with the medium and high range shifter rod 28h. The second portion 102b of the first locking element 102 defines a plurality of openings 102o adapted to receive fasteners (not shown) therein to secure the first locking element 102 to the medium and high range shift fork 32h. It is also within the scope of the invention to connect the second portion 15 102b of the first locking element 102 to the medium and high range shift fork 32h by any other means. The second portion 102b of the first locking element 102 defines a L-shape configuration. The third portion 102c of the first locking element 102 is transversely extending from the first portion 102a of the locking element 102. The third portion 102c of the first locking 20 element 102 defines a rod receiving portion 102r adapted to receive the reverse shifter rod 28r thereby enabling the movement of the first locking
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element 102 on engagement of the range lever 20 adapted to be shifted from the neutral range position (N) to the high range position (H). The fourth portion 102d of the first locking element 102 is transversely extending from the third portion 102c of the first locking element 102. The fifth portion 102e of the first locking element 102 is extending from the 5 fourth portion 102d and disposed away from the fourth portion 102d of the first locking element 102. The fifth portion 102e (as shown fig. 10) of the first locking element 102 is immediately disposed above the lever engaging portion L of the reverse shifter bush 30r on engagement of the range lever 20 adapted to be shifted from the neutral range position (N) to the high 10 range position (H), where the movement of the range lever 20 (range shift mechanism) from the neutral range position (N) to the high range position (H) facilitates engagement of the medium and high range shifter sleeve 38b with the high range dog clutch D and thereafter, corresponding portion of the speed shift lever 18 is adapted to engage the fifth portion 102e of the 15 first locking element 102 to restrict the engagement of corresponding portion 18b of the speed shift lever 18 with the lever engaging portion L of the reverse shifter bush 30r therein to restrict the movement of at least one of the speed shift lever 18, the reverse shifter bush 30r, a reverse shift fork 32r and a synchronizer sleeve of the reverse synchronizer unit 36r towards 20 the reverse gear position (R) thereby restricting the engagement of a synchronizer ring of the reverse synchronizer unit 36r with the reverse
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driven gear 34j on engagement of the gear shift lever 12 adapted to be shifted from the neutral gear position (N) towards the reverse gear position (R) when the high range dog clutch D is in engaged position, and the range shift lever 26 and the range lever 20 is in the high range position (R), where the engagement of the gear shift lever 12 adapted to be shifted towards the 5 reverse gear position (R) occurs after the engagement of the range lever 20 adapted to be shifted to the high range position (H). The fifth portion 102e of the first locking element 102 is adapted to engage corresponding portion 104p (as shown in fig. 11) of the second locking element 104 therein to restrict the movement of at least one of the range shift lever 26, a medium 10 and high range shifter bush 30h, the medium and high range shift fork 32h, and a medium and high range shifter sleeve 38b towards the high range position (H) thereby restricting the engagement of the medium and high range shifter sleeve 38b with the high range dog clutch D on engagement of the range lever 20 adapted to be shifted from the neutral range position (N) 15 towards the high range position (H) when the reverse driven gear 34j is in engaged position, and the speed shift lever 18 and the gear shift lever 12 is in the reverse gear position (R), where the engagement of the range lever 20 adapted to be shifted towards the high range position (H) occurs after the engagement of the gear shift lever 12 adapted to be shifted to the 20 reverse gear position (R). The fifth portion 102e of the first locking element 102 substantially defines a slope shape configuration. It is also
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within the scope of the invention to provide the fifth portion 102e of the first locking element 102 with at least one protrusion corresponding to the second locking element 104, where the second locking element 104 can be provided with at least one cavity therein to receive the protrusion of the fifth portion 102e of the first locking element 102 therein to restrict at least 5 one of the engagement of medium and high range shifter sleeve 38b with the high range dog clutch D when the reverse driven gear 34j is in engaged position, and the engagement of synchronizer ring (not shown) of reverse synchronizer unit 36r with reverse driven gear 34j, when the high range dog clutch D is in engaged position. Further, it is also within the scope of the 10 invention to provide the fifth portion 102e of the first locking element 102 and second locking element 104 with the aforementioned combination thereof or with any other locking means therein to restrict at least one of the engagement of medium and high range shifter sleeve 38b with the high range dog clutch D when the reverse driven gear 34j is in engaged position, 15 and the engagement of synchronizer ring (not shown) of reverse synchronizer unit 36r with reverse driven gear 34j, when the high range dog clutch D is in engaged position. The first locking element 102 substantially defines a L-shape configuration. However, it is also within the scope of the invention to provide the first locking element 102 in any other shape 20 and size without otherwise deterring the intended function of the first
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locking element 102 as can be deduced from the description and corresponding drawings.
[0045] FIG. 11 depicts a perspective view of a speed shift lever 18 and a second locking element 104 of the locking arrangement 100 in assembled condition, according to another embodiment of the invention as 5 disclosed herein. In another embodiment, the second locking element 104 is used to restrict the engagement of the medium and high range shifter sleeve 38b with the high range dog clutch D when the reverse driven gear 34j is in engaged position and the gear shift lever 12 is in the reverse gear position. The second locking element 104 is connected to the speed shift 10 lever 18. The second locking element 104 defines a portion 104p (as shown in fig. 11) adapted to be engaged by the fifth portion 102e of the first locking element 102 therein to restrict the movement of at least one of the range shift lever 26, the medium and high range shifter bush 30h, the medium and high range shift fork 32h, and the medium and high range 15 shifter sleeve 38b towards the high range position (H) thereby restricting the engagement of the medium and high range shifter sleeve 38b with the high range dog clutch D on engagement of the range lever 20 adapted to be shifted from the neutral range position (N) towards the high range position (H) when the reverse driven gear 34j is in engaged position, and the speed 20 shift lever 18 and the gear shift lever 12 is in the reverse gear position (R), where the engagement of the range lever 20 adapted to be shifted towards
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the high range position (H) occurs after the engagement of the gear shift lever 12 adapted to be shifted to the reverse gear position (R. The portion 104p of the second locking element 104 substantially defines a slope shape configuration. Further, it is also within the scope of the invention to provide any other locking means connected to the speed shift lever 18 at a 5 predefined angle without otherwise deterring the intended function of the second locking element 104 as can be deduced from the description and corresponding drawing. Furthermore, it is also within the scope of the invention to provide the second locking element 104 in any other shape and size. 10
[0046] FIG. 12b depicts a flowchart showing the steps of a method 300 for restricting at least one of the movement of a speed shift lever 18 towards a reverse gear position (R, as shown in fig. 7) thereby restricting the engagement of a reverse driven gear 34j when a range shift lever 26 is in a high range position (H, as shown in fig. 7), and the movement of the 15 range shift lever 26 towards the high range position (H, as shown in fig. 7) when the reverse driven gear 34j is in engaged position in a power transmission unit 10 of a vehicle, according to another embodiment of the invention as disclosed herein. In an embodiment, the method 300 for restricting at least one of the movement of the speed shift lever 18 towards 20 the reverse gear position (R, as shown in fig. 7) thereby restricting the engagement of the reverse driven gear 34j when the range shift lever 26 is
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in the high range position (H, as shown in fig. 7), and the movement of the range shift lever 26 towards the high range position (H, as shown in fig. 7) when the reverse driven gear 34j is in engaged position in the power transmission unit 10 of the vehicle is as follows, the method 300 comprising, providing a locking arrangement 100 comprising a first locking 5 element 102; and a second locking element 104 adapted to be connected to a speed shift lever 18 (step 302); moving the first locking element 102 in a direction towards a reverse shifter bush 30r enables a fifth portion 102e of the first locking element 102 to be disposed immediately above a lever engaging portion L of the reverse shifter bush 30r in response to the 10 movement of the range shift lever 26 from a neutral range position (N, as shown in fig. 7) to the high range position (H, as shown in fig. 7) on engagement of a range lever 20 adapted to be shifted from the neutral range position (N, as shown in fig. 9b) to the high range position (H, as shown in fig. 9b), where the engagement of the range lever 20 from the neutral range 15 position (N, as shown in fig. 9b) to the high range position (H, as shown in fig. 9b) moves at least one of the range shift lever 26, the reverse shifter bush 30r, the medium and high range shift fork 32h, and a medium and high range shifter sleeve 38b to the high range position (H, as shown in fig. 7) thereby facilitating engagement of the medium and high range shifter 20 sleeve 38b with a high range dog clutch D (step 304); moving the speed shift lever 18 in the direction towards the reverse shifter bush 30r enables
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corresponding portion of the speed shift lever 18 to engage the fifth portion 102e of the first locking element 102 to restrict the engagement of corresponding portion 18b of the speed shift lever 18 with the lever engaging portion L of the reverse shifter bush 30r therein to restrict the movement of at least one of the speed shift lever 18, a reverse shifter bush 5 30r, a reverse shift fork 32r and a synchronizer sleeve of a reverse synchronizer unit 36r towards the reverse gear position (R, as shown in fig. 7) thereby restricting the engagement of a synchronizer ring of the reverse synchronizer unit 36r with the reverse driven gear 34j on engagement of a gear shift lever 12 adapted to be shifted from a neutral gear position (N, as 10 shown in fig. 9a) towards the reverse gear position (R, as shown in fig. 9a) when the high range dog clutch D is in engaged position, and the range shift lever 26 and the range lever 20 is in the high range position (R, as shown in fig. 7 and fig 9b) (step 306); moving the fifth portion 102e of the first locking element 102 away from the lever engaging portion L of the 15 reverse shifter bush 30r in response to the movement of the range shift lever 26 from the high range position (H, as shown in fig. 7) to the neutral range position (N, as shown in fig. 7) on engagement of the range lever 20 adapted to be shifted from the high range position (H, as shown in fig. 9b) to the neutral range position (N, as shown in fig. 9b) (step 308); moving the 20 speed shift lever 18 in the direction towards the reverse shifter bush 30r facilitates engagement of corresponding portion 18b of said speed shift
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lever 18 with the lever engaging portion L of the reverse shifter bush 30r therein to move at least one of said speed shift lever 18, the reverse shifter bush 30r, the reverse shift fork 32r and the synchronizer sleeve of the reverse synchronizer unit 36r to the reverse gear position (R, as shown in fig. 7) thereby facilitating engagement of the synchronizer ring of the 5 reverse synchronizer unit 36r with the reverse driven gear 34j on engagement of the gear shift lever 12 adapted to be shifted from the neutral gear position (N, as shown in fig. 9a) to the reverse gear position (R, as shown in fig. 9a) when the range shift lever 26 and the range lever 20 is in the neutral range position (N, as shown in fig. 7 and fig 9b) (step 310); and 10 moving the first locking element 102 in the direction towards the speed shift lever 18 enables the fifth portion 102e of the first locking element 102 to engage corresponding portion 104p of the second locking element 104 therein to restrict the movement of at least one of the range shift lever 26, the reverse shifter bush 30r, the medium and high range shift fork 32h, and 15 the medium and high range shifter sleeve 38b to the high range position (H, as shown in fig. 7) thereby restricting engagement of the medium and high range shifter sleeve 38b with the high range dog clutch D when the reverse driven gear 34j is in engaged position, and the speed shift lever 18 and the gear shift lever 12 is in the reverse gear position (R, as shown in fig. 7 and 20 fig. 9a) (step 312).
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[0047] The working of the locking arrangement 100 in the power transmission unit 10 (according to another embodiment) in conjunction with the method 300 for restricting at least one of the movement of the speed shift lever 18 towards the reverse gear position (R, as shown in fig. 7) thereby restricting the engagement of the reverse driven gear 34j when 5 the range shift lever 26 is in the high range position (H, as shown in fig. 7), and the movement of the range shift lever 26 towards the high range position (H, as shown in fig. 7) when the reverse driven gear 34j is in engaged position in the power transmission unit 10 of the vehicle is as follows. When the operator (user) engages the range lever 20 adapted to be 10 moved/shifted from the neutral range position (N, as shown in fig. 9b) to the high range position (H, as shown in fig. 9b), the range lever 20 moves the range crossrod link 22 therein to move the range crossrod 24 in a predefined direction (right direction) along x-axis thereby enabling corresponding portion (not shown, can be considered as ball portion) of the 15 range shift lever 26 to engage the lever engaging portion Z (as shown in fig. 2) of the medium and high range shifter bush 30h, and also to move (turn) the range crossrod 24 in a predefined direction (counter-clockwise direction) along x-axis therein to enable corresponding portion (not shown, ball portion) of the range shift lever 26 to move the medium and high range 20 shifter bush 30h to the high range position (H, as shown in fig. 7) thereby moving the medium and high range shifter rod 28h in a predefined
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direction (backward direction) along y-axis thereby enabling the medium and high range shift fork 32h to move the medium and high range shifter sleeve 38b towards the high range dog clutch D thereby facilitating engagement of the medium and high range shifter sleeve 38b with the high range dog clutch D, where the first locking element 102 is adapted to move 5 in a direction towards the reverse shifter bush 30r thereby enabling the fifth portion 102e of the first locking element 102 to be disposed immediately above the lever engaging portion L of the reverse shifter bush 30r when the range shift lever 26 moves to the high range position (H, as shown in fig. 7) on engagement of the range lever 20 adapted to be shifted/moved from the 10 neutral range position (N, as shown in fig. 9b) to the high range position (H, as shown in fig. 9b) thereby facilitating engagement of the medium and high range shifter sleeve 38b with the high range dog clutch D. Thereafter, when the operator engages the gear shift lever 12 adapted to be moved/shifted from the neutral gear position (N, as shown in fig. 9a) 15 towards the reverse gear position (R, as shown in fig. 9a), the gear shift lever 12 moves the speed crossrod link 14 therein to move the speed crossrod 16 in a predefined direction (right direction) along x-axis therein to move the speed shift lever 18 towards the reverse shifter bush 30r thereby enabling corresponding portion of the speed shift lever 18 to 20 engage the fifth portion 102e of the first locking element 102 therein to restrict the engagement of the portion 18b of the speed shift lever 18 with
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the lever engaging portion L of the reverse shifter bush 30r therein to restrict the movement of at least one of speed shift lever 12, the reverse shifter bush 30r, the reverse shift fork 32r and the synchronizer sleeve (not shown) of the reverse synchronizer unit 36r towards the reverse gear position (R, as shown in fig. 7) thereby restricting the engagement of the 5 synchronizer ring (not shown) of the reverse synchronizer unit 36r with the reverse driven gear 34j on engagement of the gear shift lever 12 adapted to be shifted from the neutral gear position (N, as shown in fig. 9a) towards the reverse gear position (R, as shown in fig. 9a) when the range lever 20 and the range shift lever 26 is in the high range position (R, as shown in fig. 10 9b and fig. 7), and the high range dog clutch D is in engaged position, where the engagement of the gear shift lever 12 adapted to be shifted from the neutral gear position (N, as shown in fig. 9a) towards the reverse gear position (R, as shown in fig. 9a) occurs after the engagement of the range lever 20 adapted to be shifted from the neutral range position (N, as shown 15 in fig. 9b) to the high range position (H, as shown in fig. 9b).
[0048] Now, when the operator engages the gear shift lever 12 adapted to moved/shifted from the neutral gear position (N, as shown in fig. 9a) to the reverse gear position (R, as shown in fig. 9b), the gear shift lever 12 moves the speed crossrod link 14 therein to move the speed crossrod 16 20 in a predefined direction (right direction) along x-axis thereby enabling the portion 18b (ball portion) of the speed shift lever 18 to engage the lever
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engaging portion L of the reverse shifter bush 30r, and also to move (turn) the speed crossrod 16 in a predefined direction (counter-clockwise direction) along x-axis therein to enable the portion 18b of the speed shift lever 18 to move the reverse shifter bush 30r to the reverse gear position (R, as shown in fig. 7) thereby moving the reverse shifter rod 28r in a 5 predefined direction (reverse direction) along y-axis thereby enabling the reverse shift fork 32r to move corresponding synchronizer sleeve (not shown) of the reverse synchronizer unit 36r to move towards the reverse gear position (R, as shown in fig. 7) thereby moving corresponding synchronizer ring (not shown) of the reverse synchronizer unit 36r towards 10 the reverse driven gear 34j thereby facilitating engagement of synchronizer ring (not shown) of the reverse synchronizer unit 36r with the reverse driven gear 34j. Thereafter, when the operator engages the range lever 20 adapted to be moved/shifted from the neutral range position (N, as shown in fig. 9b) towards the high range gear position (H, as shown in fig. 9b), the 15 range lever 20 moves the range crossrod link 22 therein to move the range crossrod 24 in a predefined direction (right direction) along x-axis thereby enabling corresponding portion (not shown, ball portion) of the range shift lever 26 to engage the lever engaging portion Z of the medium and high range shifter bush 30h, and also to move (turn) the range crossrod 24 in a 20 predefined direction (counter-clockwise direction) along x-axis therein to enable corresponding portion (not shown, ball portion) of the range shift
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lever 26 to move the medium and high range shifter bush 30h towards the high range position (H, as shown in fig. 7) thereby moving the medium and high range shifter rod 28h in a predefined direction (backward direction) along y-axis therein to move the first locking element 102 in the direction towards the speed shift lever 18 thereby enabling the fifth portion 102e of 5 the first locking element 102 to engage corresponding portion 104p of the second locking element 104 therein to restrict the movement of at least one of the range shift lever 26, the reverse shifter bush 30r, the medium and high range shift fork 32h, and the medium and high range shifter sleeve 38b to the high range position (H, as shown in fig. 7) thereby restricting 10 engagement of the medium and high range shifter sleeve 38b with the high range dog clutch D when the reverse driven gear 34j is in engaged position, and the speed shift lever 18 and the gear shift lever 12 is in the reverse gear position (R, as shown in fig. 7 and fig. 9a), where the engagement of the range lever 20 adapted to be shifted from the neutral gear position (N, as 15 shown in fig. 9b) towards the high range position (H, as shown in fig. 9b) occurs after the engagement of the gear shift lever 12 adapted to be shifted from the neutral gear position (N, as shown in fig. 9a) to the reverse gear position (R, as shown in fig. 9a).
[0049] Therefore, a locking arrangement 100 in a power 20 transmission unit 10 and a method (200 and 300), which restricts the movement of a gear shift mechanism (gear shift lever 12 and/or speed shift
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lever 18) from a neutral gear position (N, as shown in fig. 9a and fig. 7) towards a reverse gear position (R, fig. 9a) thereby restricting engagement of a reverse driven gear 34j when a range shift mechanism (range lever 20 and/or range shift lever 26) is in a high range position (H, as shown in fig. 9b and fig. 7) and a high range dog clutch D is in engaged position, and 5 also restricts the movement of the range shift mechanism (range lever 20 and/or range shift lever 26) from a neutral range position (N, as shown in fig. 9b and fig. 7) towards the high range position (H, as shown in fig. 9b and fig. 7) when the reverse driven gear 34j is in engaged position and gear shift mechanism (gear shift lever 12 and/or speed shift lever 18) is in the 10 reverse gear position (R, as shown in fig. 9a and fig. 7) is provided for a vehicle.
[0050] The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various 15 applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of 20 limitation. Therefore, while the embodiments herein have been described in terms of embodiments, those skilled in the art will recognize that the
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embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.

CLAIMS
We claim,
1. A locking arrangement 100 in a power transmission unit 10 of a vehicle, said locking arrangement 100 comprising:
a first locking element 102 adapted to be removably connected to a medium and high range shift fork 32h; and
a speed shift lever 18 defining a locking element 18a, said speed shift lever 18 adapted to be mounted to a speed crossrod 16,
wherein
said first locking element 102 is adapted to move in a direction towards a reverse shifter bush 30r thereby enabling corresponding portion of said first locking element 102 to be disposed immediately above a lever engaging portion L of the reverse shifter bush 30r when a range shift lever 26 is in a high range position (H), and moving said speed shift lever 18 in a direction towards the reverse shifter bush 30r thereby enabling corresponding portion of said speed shift lever 18 to engage corresponding portion of said first locking element 102 to restrict the engagement of corresponding portion 18b of said speed shift lever 18 with the lever engaging portion L of the reverse shifter bush 30r therein to restrict the movement of said speed shift lever 18 towards a reverse gear position (R) thereby restricting the engagement of a reverse driven gear 34j when the range shift lever 26 is in the high range position (H), where the movement
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of said speed shift lever 18 is restricted towards the reverse gear position (R) occurs after the movement of the range shift lever 26 to the high range position (H); and
moving said first locking element 102 in a direction towards said speed shift lever 18 thereby enabling corresponding portion of said first locking element 102 to engage corresponding portion of the locking element 18a of said speed shift lever 18 therein to restrict the movement of at least one of the range shift lever 26, and the medium and high range shift fork 32h towards the high range position (H) when the reverse driven gear 34j is in engaged position and said speed shift lever 18 is in the reverse gear position (R), where the movement of at least one of the range shift lever 26, and the medium and high range shift fork 32h is restricted towards the high range position (H) occurs after the movement of said speed shift lever 18 to the reverse gear position (R).
2. The locking arrangement 100 as claimed in claim 1, wherein said first locking element 102 having a first portion 102a extending along the widthwise direction of the power transmission unit 10; a second portion 102b extending from the first portion 102a and disposed away from the first portion 102a; a third portion 102c transversely extending from the first portion 102a; a fourth portion 102d transversely extending from the third portion 102c; a fifth portion 102e extending from the fourth portion 102d
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and disposed away from the fourth portion 102d, where the fifth portion 102e substantially defines a slope shape configuration, and a sixth portion 102f transversely extending from the first portion 102a and connected to the third portion 102c, where the sixth portion 102f is adapted to provide stiffness to the third portion 102c of said first locking element 102.
3. The locking arrangement 100 as claimed in claim 2, wherein the fifth portion 102e of said first locking element 102 is adapted to engage corresponding portion 18p of the locking element 18a of said speed shift lever 18 therein to restrict the movement of at least one of the range shift lever 26, a medium and high range shifter bush 30h, the medium and high range shift fork 32h, and a medium and high range shifter sleeve 38b towards the high range position (H) thereby restricting the engagement of the medium and high range shifter sleeve 38b with a high range dog clutch D on engagement of a range lever 20 adapted to be shifted from a neutral range position (N) towards the high range position (H) when the reverse driven gear 34j is in engaged position, and said speed shift lever 18 and a gear shift lever 12 is in the reverse gear position (R), where the engagement of the range lever 20 adapted to be shifted towards the high range position (H) occurs after the engagement of the gear shift lever 12 adapted to be shifted to the reverse gear position (R).
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4. The locking arrangement 100 as claimed in claim 3, wherein the portion 18p of the locking element 18a of said speed shift lever 18 substantially defines a slope shape configuration.
5. The locking arrangement 100 as claimed in claim 4, wherein said first locking element 102 is adapted to move in a direction towards the reverse shifter bush 30r thereby enabling the fifth portion 102e of said first locking element 102 to be disposed immediately above the lever engaging portion L of the reverse shifter bush 30r when the range shift lever 26 moves to the high range position (H) on engagement of the range lever 20 adapted to be shifted from the neutral range position (N) to the high range position (H), and a portion of said speed shift lever 18 is adapted to engage the fifth portion 102e of said first locking element 102 to restrict the engagement of corresponding portion 18b of said speed shift lever 18 with the lever engaging portion L of the reverse shifter bush 30r therein to restrict the movement of at least one of said speed shift lever 18, a reverse shifter bush 30r, a reverse shift fork 32r and a synchronizer sleeve of a reverse synchronizer unit 36r towards the reverse gear position (R) thereby restricting the engagement of a synchronizer ring of the reverse synchronizer unit 36r with the reverse driven gear 34j on engagement of the gear shift lever 12 adapted to be shifted from a neutral gear position (N) towards the reverse gear position (R) when the high range dog clutch D is
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in engaged position, and the range shift lever 26 and the range lever 20 is in the high range position (R), where the engagement of the gear shift lever 12 adapted to be shifted towards the reverse gear position (R) occurs after the engagement of the range lever 20 adapted to be shifted to the high range position (H).
6. The locking arrangement 100 as claimed in claim 5, wherein the second portion 102b of said first locking element 102 is removably connected to the medium and high range shift fork 32h, where the second portion 102b of said first locking element 102 defines a plurality of openings 102o adapted to receive fasteners therein to secure said first locking element 102 to the medium and high range shift fork 32h.
7. The locking arrangement 100 as claimed in claim 1, wherein the power transmission unit 10 is at least a manual power transmission unit.
8. The locking arrangement 100 as claimed in claim 1 can be configured to be provided in at least one of an automatic power transmission unit, an automated manual power transmission unit and a hydro-static power transmission unit.
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9. The locking arrangement 100 as claimed in claim 1, wherein the vehicle is at least a tractor.
10. The locking arrangement 100 as claimed in claim 1, wherein the vehicle is an off-road vehicle.
11. A method 200 for restricting at least one of the movement of a speed shift lever 18 towards a reverse gear position (R) thereby restricting the engagement of a reverse driven gear 34j when a range shift lever 26 is in a high range position (H), and the movement of the range shift lever 26 towards the high range position (H) when the reverse driven gear 34j is in engaged position in a power transmission unit 10 of a vehicle, said method 200 comprising:
providing a locking arrangement 100 comprising a first locking element 102; and a speed shift lever 18 defining a locking element 18a;
moving said first locking element 102 in a direction towards a reverse shifter bush 30r enables corresponding portion of said first locking element 102 to be disposed immediately above a lever engaging portion L of the reverse shifter bush 30r in response to the movement of the range shift lever 26 from a neutral range position (N) to the high range position (H);
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moving said speed shift lever 18 in a direction towards the reverse shifter bush 30r enables corresponding portion of said speed shift lever 18 to engage corresponding portion of said first locking element 102 to restrict the engagement of corresponding portion 18b of said speed shift lever 18 with the lever engaging portion L of the reverse shifter bush 30r therein to restrict the movement of said speed shift lever 18 towards the reverse gear position (R) thereby restricting the engagement of the reverse driven gear 34j when the range shift lever 26 is in the high range position (H);
moving corresponding portion of said first locking element 102 away from the lever engaging portion L of the reverse shifter bush 30r in response to the movement of the range shift lever 26 from the high range position (H) to the neutral range position (N);
moving said speed shift lever 18 in a direction towards the reverse shifter bush 30r to facilitate engagement of corresponding portion 18b of said speed shift lever 18 with the lever engaging portion L of the reverse shifter bush 30r therein to move said speed shift lever 18 to the reverse gear position (R) thereby facilitating engagement of the reverse driven gear 34j when the range shift lever 26 is in the neutral range position (N); and
moving said first locking element 102 in a direction towards said speed shift lever 18 thereby enabling corresponding portion of said first locking element 102 to engage corresponding portion of the locking element 18a of said speed shift lever 18 therein to restrict the movement of
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at least one of the range shift lever 26, and the medium and high range shift fork 32h towards the high range position (H) when the reverse driven gear 34j is in engaged position and said speed shift lever 18 is in the reverse gear position (R).
12. The method 200 as claimed in claim 11, wherein said first locking element having a first portion 102a extending along the widthwise direction of the power transmission unit 10; a second portion 102b extending from the first portion 102a and disposed away from the first portion 102a; a third portion 102c transversely extending from the first portion 102a; a fourth portion 102d transversely extending from the third portion 102c; a fifth portion 102e extending from the fourth portion 102d and disposed away from the fourth portion 102d, where the fifth portion 102e substantially defines a slope shape configuration, and a sixth portion 102f transversely extending from the first portion 102a and connected to the third portion 102c, where the sixth portion 102f is adapted to provide stiffness to the third portion 102c of said first locking element 102.
13. The method 200 as claimed in claim 12, wherein moving said first locking element 102 in the direction towards the reverse shifter bush 30r enables the fifth portion 102e of said first locking element 102 to be disposed immediately above the lever engaging portion L of the reverse
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shifter bush 30r in response to the movement of the range shift lever 26 from a neutral range position (N) to the high range position (H) on engagement of a range lever 20 from the neutral range position (N) to the high range position (H), where the engagement of the range lever 20 from the neutral range position (N) to the high range position (H) moves at least one of the range shift lever 26, the reverse shifter bush 30r, the medium and high range shift fork 32h, and a medium and high range shifter sleeve 38b to the high range position (H) thereby facilitating engagement of the medium and high range shifter sleeve 38b with a high range dog clutch D.
14. The method 200 as claimed in claim 13, wherein moving said speed shift lever 18 in the direction towards the reverse shifter bush 30r enables corresponding portion of said speed shift lever 18 to engage the fifth portion 102e of said first locking element 102 to restrict the engagement of corresponding portion 18b of said speed shift lever 18 with the lever engaging portion L of the reverse shifter bush 30r therein to restrict the movement of at least one of said speed shift lever 18, a reverse shifter bush 30r, a reverse shift fork 32r and a synchronizer sleeve of a reverse synchronizer unit 36r towards the reverse gear position (R) thereby restricting the engagement of a synchronizer ring of the reverse synchronizer unit 36r with the reverse driven gear 34j on engagement of the gear shift lever 12 adapted to be shifted from a neutral gear position (N)
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towards the reverse gear position (R) when the high range dog clutch D is in engaged position, and the range shift lever 26 and the range lever 20 is in the high range position (R).
15. The method 200A as claimed in claim 14, wherein moving said speed shift lever 18 in the direction towards the reverse shifter bush 30r facilitates engagement of corresponding portion 18b of said speed shift lever 18 with the lever engaging portion L of the reverse shifter bush 30r therein to move at least one of said speed shift lever 18, the reverse shifter bush 30r, the reverse shift fork 32r and the synchronizer sleeve of the reverse synchronizer unit 36r to the reverse gear position (R) thereby facilitating engagement of the synchronizer ring of the reverse synchronizer unit 36r with the reverse driven gear 34j on engagement of the gear shift lever 12 adapted to be shifted from the neutral gear position (N) to the reverse gear position (R) when the range shift lever 26 and the range lever 20 is in the neutral range position (N).
16. The method 200A as claimed in claim 15, wherein moving said first locking element 102 in the direction towards said speed shift lever 18 enables the fifth portion 102e of said first locking element 102 to engage corresponding portion 18p of the locking element 18a of said speed shift lever 18 therein to restrict the movement of at least one of the range shift
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lever 26, the reverse shifter bush 30r, the medium and high range shift fork 32h, and the medium and high range shifter sleeve 38b to the high range position (H) thereby restricting engagement of the medium and high range shifter sleeve 38b with the high range dog clutch D when the reverse driven gear 34j is in engaged position, and said speed shift lever 18 and the gear shift lever 12 is in the reverse gear position (R).
17. A locking arrangement 100 in a power transmission unit 10 of a vehicle, said locking arrangement 100 comprising:
a first locking element 102 adapted to be removably connected to a medium and high range shift fork 32h; and
a second locking element 104 adapted to be connected to a speed shift lever 18, said speed shift lever 18 adapted to be mounted to a speed crossrod 16,
wherein
said first locking element 102 is adapted to move in a direction towards a reverse shifter bush 30r thereby enabling corresponding portion of said first locking element 102 to be disposed immediately above a lever engaging portion L of the reverse shifter bush 30r when a range shift lever 26 is in a high range position (H), and moving said speed shift lever 18 in a direction towards the reverse shifter bush 30r thereby enabling corresponding portion of said speed shift lever 18 to engage corresponding
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portion of said first locking element 102 to restrict the engagement of corresponding portion 18b of said speed shift lever 18 with the lever engaging portion L of the reverse shifter bush 30r therein to restrict the movement of said speed shift lever 18 towards a reverse gear position (R) thereby restricting the engagement of a reverse driven gear 34j when the range shift lever 26 is in the high range position (H), where the movement of said speed shift lever 18 is restricted towards the reverse gear position (R) occurs after the movement of the range shift lever 26 to the high range position (H); and
moving said first locking element 102 in a direction towards said speed shift lever 18 thereby enabling corresponding portion of said first locking element 102 to engage corresponding portion of said second locking element 104 therein to restrict the movement of at least one of the range shift lever 26, and the medium and high range shift fork 32h towards the high range position (H) when the reverse driven gear 34j is in engaged position and said speed shift lever 18 is in the reverse gear position (R), where the movement of at least one of the range shift lever 26, and the medium and high range shift fork 32h is restricted towards the high range position (H) occurs after the movement of said speed shift lever 18 to the reverse gear position (R).
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18. The locking arrangement 100 as claimed in claim 17, wherein said first locking element 102 having a first portion 102a extending along the widthwise direction of the power transmission unit 10; a second portion 102b extending from the first portion 102a and disposed away from the first portion 102a; a third portion 102c transversely extending from the first portion 102a; a fourth portion 102d transversely extending from the third portion 102c; and a fifth portion 102e extending from the fourth portion 102d and disposed away from the fourth portion 102d, where the fifth portion 102e substantially defines a slope shape configuration.
19. The locking arrangement 100 as claimed in claim 18, wherein the fifth portion 102e of said first locking element 102 is adapted to engage corresponding portion 104p of said second locking element 104 therein to restrict the movement of at least one of the range shift lever 26, a medium and high range shifter bush 30h, the medium and high range shift fork 32h, and a medium and high range shifter sleeve 38b towards the high range position (H) thereby restricting the engagement of the medium and high range shifter sleeve 38b with a high range dog clutch D on engagement of a range lever 20 adapted to be shifted from a neutral range position (N) towards the high range position (H) when the reverse driven gear 34j is in engaged position, and said speed shift lever 18 and a gear shift lever 12 is in the reverse gear position (R), where the engagement of the range lever
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20 adapted to be shifted towards the high range position (H) occurs after the engagement of the gear shift lever 12 adapted to be shifted to the reverse gear position (R).
20. The locking arrangement 100 as claimed in claim 19, wherein the portion 104p of said second locking element 104 substantially defines a slope shape configuration.
21. The locking arrangement 100 as claimed in claim 20, wherein said first locking element 102 is adapted to move in the direction towards the reverse shifter bush 30r thereby enabling the fifth portion 102e of said first locking element 102 to be disposed immediately above the lever engaging portion L of the reverse shifter bush 30r when the range shift lever 26 moves to the high range position (H) on engagement of the range lever 20 adapted to be shifted from the neutral range position (N) to the high range position (H), and a portion of said speed shift lever 18 is adapted to engage the fifth portion 102e of said first locking element 102 to restrict the engagement of corresponding portion 18b of said speed shift lever 18 with the lever engaging portion L of the reverse shifter bush 30r therein to restrict the movement of at least one of said speed shift lever 18, a reverse shifter bush 30r, a reverse shift fork 32r and a synchronizer sleeve of a reverse synchronizer unit 36r towards the reverse gear position (R) thereby
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restricting the engagement of a synchronizer ring of the reverse synchronizer unit 36r with the reverse driven gear 34j on engagement of the gear shift lever 12 adapted to be shifted from a neutral gear position (N) towards the reverse gear position (R) when the high range dog clutch D is in engaged position, and the range shift lever 26 and the range lever 20 is in the high range position (R), where the engagement of the gear shift lever 12 adapted to be shifted towards the reverse gear position (R) occurs after the engagement of the range lever 20 adapted to be shifted to the high range position (H).
22. The locking arrangement 100 as claimed in claim 21, wherein the second portion 102b of said first locking element 102 is removably connected to the medium and high range shift fork 32h, where the second portion 102b of said first locking element 102 defines a plurality of openings 102o adapted to receive fasteners therein to secure said first locking element 102 to the medium and high range shift fork 32h.
23. The locking arrangement 100 as claimed in claim 17, wherein the power transmission unit 10 is at least a manual power transmission unit.
24. The locking arrangement 100 as claimed in claim 17 can be configured to be provided in at least one of an automatic power transmission unit, an
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automated manual power transmission unit and a hydro-static power transmission unit.
25. The locking arrangement 100 as claimed in claim 17, wherein the vehicle is at least a tractor.
26. The locking arrangement 100 as claimed in claim 17, wherein the vehicle is an off-road vehicle.
27. A method 300 for restricting at least one of the movement of a speed shift lever 18 towards a reverse gear position (R) thereby restricting the engagement of a reverse driven gear 34j when a range shift lever 26 is in a high range position (H), and the movement of the range shift lever 26 towards the high range position (H) when the reverse driven gear 34j is in engaged position in a power transmission unit 10 of a vehicle, said method 200 comprising:
providing a locking arrangement 100 comprising a first locking element 102; and a second locking element 104 adapted to be connected to a speed shift lever 18;
moving said first locking element 102 in a direction towards a reverse shifter bush 30r enables corresponding portion of said first locking element 102 to be disposed immediately above a lever engaging portion L
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of the reverse shifter bush 30r in response to the movement of the range shift lever 26 from a neutral range position (N) to the high range position (H);
moving said speed shift lever 18 in a direction towards the reverse shifter bush 30r enables corresponding portion of said speed shift lever 18 to engage corresponding portion of said first locking element 102 to restrict the engagement of corresponding portion 18b of said speed shift lever 18 with the lever engaging portion L of the reverse shifter bush 30r therein to restrict the movement of said speed shift lever 18 towards the reverse gear position (R) thereby restricting the engagement of the reverse driven gear 34j when the range shift lever 26 is in the high range position (H);
moving corresponding portion of said first locking element 102 away from the lever engaging portion L of the reverse shifter bush 30r in response to the movement of the range shift lever 26 from the high range position (H) to the neutral range position (N);
moving said speed shift lever 18 in a direction towards the reverse shifter bush 30r to facilitate engagement of corresponding portion 18b of said speed shift lever 18 with the lever engaging portion L of the reverse shifter bush 30r therein to move said speed shift lever 18 to the reverse gear position (R) thereby facilitating engagement of the reverse driven gear 34j when the range shift lever 26 is in the neutral range position (N); and
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moving said first locking element 102 in a direction towards said speed shift lever 18 thereby enabling corresponding portion of said first locking element 102 to engage corresponding portion of said second locking element 104 therein to restrict the movement of at least one of the range shift lever 26, and the medium and high range shift fork 32h towards the high range position (H) when the reverse driven gear 34j is in engaged position and said speed shift lever 18 is in the reverse gear position (R).
28. The method 300 as claimed in claim 27, wherein said first locking element having a first portion 102a extending along the widthwise direction of the power transmission unit 10; a second portion 102b extending from the first portion 102a and disposed away from the first portion 102a; a third portion 102c transversely extending from the first portion 102a; a fourth portion 102d transversely extending from the third portion 102c; and a fifth portion 102e extending from the fourth portion 102d and disposed away from the fourth portion 102d, where the fifth portion 102e substantially defines a slope shape configuration.
29. The method 300 as claimed in claim 28, wherein moving said first locking element 102 in the direction towards the reverse shifter bush 30r enables the fifth portion 102e of said first locking element 102 to be disposed immediately above the lever engaging portion L of the reverse
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shifter bush 30r in response to the movement of the range shift lever 26 from a neutral range position (N) to the high range position (H) on engagement of a range lever 20 from the neutral range position (N) to the high range position (H), where the engagement of the range lever 20 from the neutral range position (N) to the high range position (H) moves at least one of the range shift lever 26, the reverse shifter bush 30r, the medium and high range shift fork 32h, and a medium and high range shifter sleeve 38b to the high range position (H) thereby facilitating engagement of the medium and high range shifter sleeve 38b with a high range dog clutch D.
30. The method 300 as claimed in claim 29, wherein moving said speed shift lever 18 in the direction towards the reverse shifter bush 30r enables corresponding portion of said speed shift lever 18 to engage the fifth portion 102e of said first locking element 102 to restrict the engagement of corresponding portion 18b of said speed shift lever 18 with the lever engaging portion L of the reverse shifter bush 30r therein to restrict the movement of at least one of said speed shift lever 18, a reverse shifter bush 30r, a reverse shift fork 32r and a synchronizer sleeve of a reverse synchronizer unit 36r towards the reverse gear position (R) thereby restricting the engagement of a synchronizer ring of the reverse synchronizer unit 36r with the reverse driven gear 34j on engagement of the gear shift lever 12 adapted to be shifted from a neutral gear position (N)
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towards the reverse gear position (R) when the high range dog clutch D is in engaged position, and the range shift lever 26 and the range lever 20 is in the high range position (R).
31. The method 300 as claimed in claim 30, wherein moving said speed shift lever 18 in the direction towards the reverse shifter bush 30r facilitates engagement of corresponding portion 18b of said speed shift lever 18 with the lever engaging portion L of the reverse shifter bush 30r therein to move at least one of said speed shift lever 18, the reverse shifter bush 30r, the reverse shift fork 32r and the synchronizer sleeve of the reverse synchronizer unit 36r to the reverse gear position (R) thereby facilitating engagement of the synchronizer ring of the reverse synchronizer unit 36r with the reverse driven gear 34j on engagement of the gear shift lever 12 adapted to be shifted from the neutral gear position (N) to the reverse gear position (R) when the range shift lever 26 and the range lever 20 is in the neutral range position (N).
32. The method 300 as claimed in claim 31, wherein moving said first locking element 102 in the direction towards said speed shift lever 18 enables the fifth portion 102e of said first locking element 102 to engage corresponding portion 104p of said second locking element 104 therein to restrict the movement of at least one of the range shift lever 26, the reverse
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shifter bush 30r, the medium and high range shift fork 32h, and the medium and high range shifter sleeve 38b to the high range position (H) thereby restricting engagement of the medium and high range shifter sleeve 38b with the high range dog clutch D when the reverse driven gear 34j is in engaged position, and said speed shift lever 18 and the gear shift lever 12 is in the reverse gear position (R).