FIELD OF INVENTION:
[001] The present subject matter described herein, relates to an external gearshift for a manual-shift transmission vehicle, and, in particular, to a select and return mechanism of gear shift lever in manual shift transmission vehicle. 5
BACKGROUND AND PRIOR ART:
[002] In general each manual gear shift transmission system has select return mechanism. Generally, the select return mechanism is a mechanism in which shift lever returns to a neutral position when shift lever is not in engaged position. Further, restore the neutral position of the gear shift lever by pulling it against the 10 resistances offered by the system.
[003] Generally the gear select system comprises a shift selector lever, which is moveable in a holder in two degrees of freedom and whose position by way of control cables connected to the manual-shift transmission determines a gear engaged in said manual-shift transmission. With most external gearshifts, the shift 15 selector lever is mounted in a ball joint, i.e., the two degrees of freedom are rotation degrees of freedom.
[004] Figure 1 and 2 show conventional system of GSLA with torsion spring for select return mechanism. The GSLA 100 has ball joint, in which the shift selector lever 101 is rotatably mounted, is concealed in the interior of the holder/body 102. 20 From a ball that is received in the interior of the holder 102 and connected to the shift selector lever 101 in a fixed manner an axle lever 103 stands away radially, whose tip engages with select bell crank 104 that can be rotatably mounted on fixation shaft 105 in vehicle transverse direction. In order to ensure that the shift selector lever 101 with no gear engaged always assumes a neutral position in the 25 gear select pattern, for example, H gear select pattern, a torsional coil spring 106 is arranged roundabout the fixation shaft 105, which has two arms 106a and 106b standing away radially.
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[005] When the shift selector lever 101 is deflected or moved from the neutral position to the left and right side and the axle lever 103 is lowered and upward with respect to the neutral position. During the select motion as shown the axle lever 103 moves the legs 106a, 106b of the torsional coil spring 106 up and down. During coming back to neutral position these legs 106a, 106b push back the axle 5 lever 103 to its neutral position. The torsional coil spring 106 becomes active during movement of the selector lever 101 in select direction. The axle lever 103 comes back to its neutral position due to restoration force of the torsional coil spring 106. During left side motion of the shift selector 101, the axle lever 103 deflects the lower arm 106b downwards, while the upper arm 106a is blocked on a 10 protrusion 107 of the holder or body of the GSLA 102. The tension of the torsional coil spring 106 resulting from this drives the shift selector lever 101 in direction of its neutral position until the lower arm 106b in turn strikes the bottom of the protrusion 107.
[006] In order to avoid the generation of noises during the striking of the arms 15 106a, 106b against the axle lever 103 or the protrusion 107, the arms 106a, 106b in each case are provided with an elastic covering of rubber. All this increases the costs of the external gearshift.
[007] Further, the conventional coil spring based systems has several disadvantages which are listed below: 20
[008] Due to rubbing in the coils of the torsional coil spring, noise is generated which affects overall noise feeling of the vehicle.
[009] There are losses due to friction between the coils of the torsional coil spring which affect the efficiency of the system.
[0010] One complex part, i.e., torsional coil spring is required to restore the shift 25 select lever to neutral position which adds to cost of the system.
[0011] Therefore, there is a need in the art to eliminate requirement of the torsional coil spring in the gear shift lever assembly to avoid noise and to reduce cost of the gear shift lever assembly. Further, there is a requirement to have close
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tolerances between the parts of the gear shift lever assembly. The present invention has been conceived in view of the aforementioned circumstances. The present subject matter of the invention describes the gear shift lever assembly with select and return mechanism without torsional coil spring.
OBJECTS OF THE INVENTION: 5
[0012] The principal objective of the present invention is to provide a gear shift lever assembly with select and return mechanism.
[0013] Another object of the present invention is to provide a gear shift lever assembly with integrated select and return mechanism.
[0014] Another object of the present invention is to provide a gear shift lever 10 assembly without torsional coil spring.
[0015] Another object of the present invention is to provide a gear shift lever assembly with two metal legs for select and return mechanism.
[0016] Another object of the present invention is to provide a gear shift lever assembly having close tolerances between axle lever of the select shift lever, 15 protrusion and metal legs for avoid noise.
[0017] Yet another object of the present invention is to provide a simple, effective, and cost efficient gear shift lever which eliminates the requirement of the costly torsional coil spring.
SUMMARY OF THE INVENTION: 20
[0018] The subject matter disclosed herein relates to a gear shift lever assembly (GSLA) for select return mechanism of shift lever during select operation. The gear shift lever assembly has a select lever that is configured to move in shift degree of freedom and selector degree of freedom. The select lever is rotatably mounted in a ball joint for selecting the gear and correspondingly changing the 25 gear in select direction. The select lever is assembled in a holder that can be made of plastic or metal or combination of plastic and metal. Further, a axle lever is coupled with the select lever and extend in perpendicular direction away from the
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ball joint of the select lever in order to follow a movement of select lever in the selector degree of freedom. The holder has fixation shaft for holding a bell crank. The bell crank is coupled with the axle lever from one end and select and shift cable from other end to transfer select and shift motion from the select lever to gear box. In the present subject matter, two bent metal legs are used for select 5 return mechanism of the select lever. The two bent metal legs are molded in the holder around the fixation shaft from one end and other end rests on protrusion which extends away from the holder in direction of the axle lever. The two bent metal legs configured to act on the axle lever during select operation and restore force applied during select operation and further configured to push the axle lever 10 into neutral position of the selector degree of freedom.
[0019] In order to further understand the characteristics and technical contents of the present subject matter, a description relating thereto will be made with reference to the accompanying drawings. However, the drawings are illustrative only but not used to limit scope of the present subject matter. 15
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] It is to be noted, however, that the appended drawings illustrate only typical embodiments of the present subject matter and are therefore not to be considered for limiting of its scope, for the invention may admit to other equally effective embodiments. The detailed description is described with reference to the 20 accompanying figures. In the figures, the left-most digit(s) of a reference number identifies the figure in which the reference number first appears. The same numbers are used throughout the figures to reference like features and components. Some embodiments of system or methods in accordance with embodiments of the present subject matter are now described, by way of example, 25 and with reference to the accompanying figures, in which:
[0021] Fig. 1 and 2 illustrate conventional Gear shift Lever Assembly (GSLA) with torsional spring;
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[0022] Fig. 3 illustrates assembled and exploded view of Gear shift Lever Assembly (GSLA) with two bent metal legs for select return mechanism, in accordance with an embodiment of the present subject matter;
[0023] Fig. 4 illustrate side view of the Gear shift Lever Assembly (GSLA) with two bent metal legs, in accordance with an embodiment of the present subject 5 matter;
[0024] Fig. 5 illustrates exploded view of the Gear shift Lever Assembly (GSLA) with two bent metal legs of figure 3, in accordance with an embodiment of the present subject matter;
[0025] Fig. 6 illustrates structure of the two bent metal legs of figure 3, in 10 accordance with an embodiment of the present subject matter; and
[0026] Fig. 7 illustrates position of the two bent metal legs with axle lever and fixation shaft of the GSLA of figure 3, in accordance with an embodiment of the present subject matter.
[0027] The figures depict embodiments of the present subject matter for the 15 purposes of illustration only. A person skilled in the art will easily recognize from the following description that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the disclosure described herein.
DESCRIPTION OF THE PREFERRED EMBODIMENTS: 20
[0028] The subject matter disclosed herein relates to a gear shift lever assembly (GSLA) for select return mechanism of shift lever during select operation. The gear shift lever assembly has a select lever that is configured to move in shift degree of freedom and selector degree of freedom. The select lever is rotatably mounted in a ball joint for selecting the gear and correspondingly changing the 25 gear in select direction. The select lever is assembled in a holder that can be made of plastic or metal or combination of plastic and metal. Further, a axle lever is coupled with the select lever and extend in perpendicular direction away from the ball joint of the select lever in order to follow a movement of select lever in the
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selector degree of freedom. The holder has fixation shaft for holding a bell crank. The bell crank is coupled with the axle lever from one end and select and shift cable from other end to transfer select and shift motion from the select lever to gear box. In the present subject matter, two bent metal legs are used for select return mechanism of the select lever. The two bent metal legs are molded in the 5 holder around the fixation shaft from one end and other end rests on protrusion which extends away from the holder in direction of the axle lever. The two bent metal legs configured to act on the axle lever during select operation and restore force applied during select operation and further configured to push the axle lever into neutral position of the selector degree of freedom. During the select motion of 10 the axle lever, the axle lever moves the two bent metal legs and during coming back to neutral position these two bent metal legs push back the axle lever to its neutral position. The bent metal legs become active during movement of GSLA in select direction. The select lever comes back to neutral position due to restoration force of the two bent metal legs. In the present subject matter, there is no 15 requirement of costly torsional coil spring for select return mechanism. Further, bent in the two bent metal legs provide close tolerances between the axle lever, bent metal legs which restrict movement of the axle lever in vehicle running condition and avoid generation of rattling sound in the GSLA.
[0029] It should be noted that the description and figures merely illustrate the 20 principles of the present subject matter. It should be appreciated by those skilled in the art that conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present subject matter. It should also be appreciated by those skilled in the art that by devising various assembly that, although not explicitly 25 described or shown herein, embody the principles of the present subject matter and are included within its scope. Furthermore, all examples recited herein are principally intended expressly to be for pedagogical purposes to aid the reader in understanding the principles of the present subject matter and the concepts contributed by the inventor(s) to furthering the art, and are to be construed as 30 being without limitation to such specifically recited examples and conditions. The
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novel features which are believed to be characteristic of the present subject matter, both as to its organization and method of operation, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures.
[0030] These and other advantages of the present subject matter would be 5 described in greater detail with reference to the following figures. It should be noted that the description merely illustrates the principles of the present subject matter. It will thus be appreciated that those skilled in the art will be able to devise various arrangements that, although not explicitly described herein, embody the principles of the present subject matter and are included within its scope. 10
[0031] In the present GSLA, the torsion spring has been eliminated for select return mechanism. Instead of torsion spring, two metal legs have been molded in to the housing of the GSLA. The metal two legs become active during select operation and provide required restoration. The legs rest on protrusion of the housing. During the select motion, the axle lever moves the legs and during 15 coming back to neutral these legs push back the axle lever to its neutral position. Detailed explanation and working of the present subject matter is described in the following figures.
[0032] Fig. 3 illustrates structure of gear shift lever assembly (GSLA) with two bent metal legs for select return mechanism, in accordance with an embodiment of 20 the present subject matter. The gear shift lever assembly 300 has a select lever 301 which is configured to move in shift degree of freedom and select degree of freedom. There can be any pattern, for example, H selection pattern for selection of gears in the vehicles. In the select degree of freedom of the H selection pattern, the select lever 301 can move in H pattern for selection and shifting of different 25 gears. Generally in the vehicle transmission systems, the gears are selected first and then shifting is happened. The select lever 301 is rotatably mounted in a ball joint 301a of holder 302. The holder 302 is a housing that has different grooves and protrusion for holding parts of the gear shift lever assembly. The holder 302 is mounted on the floor or central console of the vehicle. An axle lever 303 is 30
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coupled to the select lever 301 and extends perpendicularly away from the ball joint 301a of the select lever 301. The axle lever 303 directs movement of the select lever 301 in the selector degree of freedom. On the other end, the axle lever 303 is coupled with a bell crank 304 to transfer select and shift motion. The bell crank 304 coupled with shift and select cable of the vehicle transmission system 5 for transferring the corresponding motion to gear box.
[0033] The holder 302 has a fixation shaft 305 to mount the bell crank 304 in the assembly. The bell crank 304 receives circular end of the axle lever 303. Further, the fixation shaft 305 is integrated molded in the holder 302 and extends ways from the holder 302 in direction of the axle lever 303. On opposite side that on 10 other side of the axle lever 303, the holder 302 has a protrusion 307 which extend away from the side of the holder 302 in direction of the axle lever 303.
[0034] As shown in the figure 4 and 5, 5he gear shift lever assembly 300 has two bent metal legs 306a, 306b that are mounted around the axle lever 303. As shown in the figure 4, the two bent medal legs 306a, 306b are molded into the holder 15 303. As shown in the figure 4, first bent metal leg 306a is molded at upper side of the fixation shaft 305 and second bent metal leg 306b is molded in the holder at lower side of the fixation shaft 305. The two bent metal legs 306a, 306b define a ‘<’ shaped profile to cover the axle lever 303. After covering the axle lever 303, the two bent metal legs 306a, 306b rest on the protrusion 307 of the holder 302. 20 The two bent metal legs 306a, 306b configured to act on axle lever 303 during select operation and further configured to load the axle lever 303 into a neutral position of the select degree of freedom. The axle lever 303 is in close tolerance with the two bent metal legs 306a, 306b. Further, the first bent metal leg 306a has tension in downward direction and the second bent metal leg 306b has tension in 25 upward direction. Therefore, the axle lever 303 is tightly coupled in between the two bent metal legs 306a, 306b.
[0035] When axle lever 303 moves upward direction according to select pattern, the axle lever 303 pushes the first leg 306a in upward direction. Due to push, the first leg 306a stores the push force that helps the axle lever 303 to regain its 30
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neutral position with less force on the select lever 301. Similarly, when the axle lever 303 moves downward direction according to select pattern, the axle lever 303 pushes the second leg 306b in downward direction. Due to push, the second leg 306b stores the push force that helps the axle lever 303 to regain its neutral position with less force on the select lever 301. In this way, the two bent metal 5 legs 306a, 306b helps in select return mechanism.
[0036] Fig. 6 illustrates structure of the two bent metal legs for select return mechanism in the gear shift lever assembly, in accordance with an embodiment of the present subject matter. The two bent metal leg structure 600 has two legs, i.e., first leg 601 (same as first leg 306a) and second leg 602 (same as second leg 10 306b). In the complete specification of the present subject matter, the two bent metal legs 306a, 306b interchangeably can be referred as two bent metal legs 601, 602. In the description of the figure 6, the two bent metal legs are referred with reference numeral 601, 602. The second bent metal leg 602 is mirror image of the first bent metal leg 601 along the axis X-X. Both the legs have same dimensions 15 and bend angles. The two bent metal legs 601, 602 has two ends one is fixed end and other is free end. Further, dimensions and bend angle of both the legs can be optimized as per size and shape of the gear shift lever assembly. Therefore, any size and shape with present structure of the two bent metal legs are within the scope of the present invention. 20
[0037] As shown in the figure 6, the first bent metal leg 601 is molded into the holder 302 from the fixed end 601a. Further, the first bent metal leg 601 bends in downward direction upto bent point 601ab to cover circular circumference of the fixation shaft 305 and inclined in upward direction from the bent point 601ab to cover the axle lever 303 and matches with shape and dimensions of the axle lever 25 303 as shown in the figure 7.
[0038] The second bent metal leg 602 is mirror image of the first bent metal leg 601. The second bent metal leg 602 has same dimension and bent profile as of first bent metal leg 601. Similarly, the second bent metal leg 602 is molded into the holder 302 from fixed end 602b. Further, the second bent metal leg 602 bends 30
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in upward direction upto bent point 602bb to cover circular circumference of the fixation shaft 305 and bent in downward direction from the bent point 602bb to go below the axle lever 303 and matches with shape and dimensions of the axle lever 303 as shown in the figure 7. As shown from the figures 3-7, both the legs 601, 602 have same dimensions and bent profile. 5
[0039] The free end 601ac of the first metal bent leg 601 rests on upper surface of the protrusion 307 that extends outwardly away from the holder 302 in direction along the axle lever 303. On the other hand free end 602bc of the second mental bent leg 602 rests on the lower surface of the protrusion 307 of the holder. The protrusion 307 restricts movement of the legs beyond the specified point. 10
[0040] As shown in the figure 7, the bent points 601ab, 602bb of the two bent metal legs 601, 602, respectively, are present in between the fixation shaft 305 and the axle lever 303 that provide close tolerance between the axle lever 303, the two bent metal legs 601, 602, and the protrusion 307 during select return mechanism for avoiding or eliminating rattling sound which generates in between 15 the legs of the torsional coil spring and the axle lever and in between the legs of the torsional coil spring and the protrusions. In the present subject matter, the shape and dimensions of the two bent metal legs 601, 602, the axle lever 303, and the protrusion 307 matches with one another and have close tolerances to eliminate free of play of the select lever 301 during neutral position. 20
[0041] The select return mechanism of the present subject matter has two bent metal legs that have been molded in to the housing of the GSLA from one end. The two bent metal legs become active during select operation and provide required restoration. The two bent metal legs rest on the protrusion from other free end. During the select motion of the axle lever, the axle lever moves the legs and 25 during coming back to neutral these legs push back the axle lever to its neutral position. The legs become active during movement of GSLA in select direction. The lever comes back to neutral due to restoration force of legs.
[0042] With the present two bent leg structure, requirement of the torsional coil spring has been eliminated. With the elimination of the torsional coil spring, the 30
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technical problem associated with the spring has been eliminated also. The present subject matter has better Noise, Vibration, and Harshness (NVH) characteristics as the rubbing noise of coils present in the earlier system has been eliminated.The frictional losses of coil is also eliminated as coils have been eliminated in the current system. There is reduction in cost due to replacement of complex child 5 part, i.e., torsional coil spring with extending legs with simple child part, i.e., two bent metal legs.
[0043] The term “vehicle” as used throughout this detailed description and in the claims refers to any moving vehicle that is capable of carrying one or more human occupants and is powered by any form of energy. The term “vehicle” is a motor 10 vehicle which includes, but is not limited to: cars, trucks, vans, minivans, hatchback, sedan, MUVs, and SUVs.
[0044] It will be further appreciated that functions or structures of a plurality of components or steps may be combined into a single component or step, or the functions or structures of one-step or component may be split among plural steps 15 or components. The present invention contemplates all of these combinations. Unless stated otherwise, dimensions and geometries of the various structures depicted herein are not intended to be restrictive of the invention, and other dimensions or geometries are possible. In addition, while a feature of the present invention may have been described in the context of only one of the illustrated 20 embodiments, such feature may be combined with one or more other features of other embodiments, for any given application. It will also be appreciated from the above that the fabrication of the unique structures herein and the operation thereof also constitute methods in accordance with the present invention. The present invention also encompasses intermediate and end products resulting from the 25 practice of the methods herein. The use of “comprising” or “including” also contemplates embodiments that “consist essentially of” or “consist of” the recited feature.
[0045] Although embodiments for the present subject matter have been described in language specific to structural features, it is to be understood that the present 30
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subject matter is not necessarily limited to the specific features described. Rather, the specific features and methods are disclosed as embodiments for the present subject matter. Numerous modifications and adaptations of the system/component of the present invention will be apparent to those skilled in the art, and thus it is intended by the appended claims to cover all such modifications and adaptations 5 which fall within the scope of the present subject matter.

We claim:
1. A gear shift lever assembly (GSLA) (300) for vehicle shift transmission and select return mechanism, the gear shift lever assembly (GSLA) (300) comprising:
a select lever (301) that is configured to move in a shift degree of 5 freedom and a selector degree of freedom, wherein the select lever (301) is rotatably mounted in ball joint of holder (302);
a axle lever (303) coupled to the select lever (301) and extend perpendicularly away from base of the select lever (301) in order to follow a movement of the select lever (301) in the selector degree of freedom; 10
characterized in that
two bent metal legs (600, 306a, 306b) molded into the holder (302), wherein first bent metal leg (601, 306a) is molded at upper side of fixation shaft (305) which is integrated with the holder (302) and second bent metal leg (602, 306b) is molded at lower side of fixation shaft (305), wherein the 15 two bent metal legs (306a, 306b) configured to act on the axle lever (303) during select operation and further configured to load the axle lever (303) into a neutral position of the selector degree of freedom.
2. The gear shift lever assembly (GSLA) (300) as claimed in claim 1, wherein 20 the two bent metal legs (600) comprise:
first bent metal leg (601) molded into the holder (302) from fixed end (601a), the first bent metal leg (601) bends in downward direction upto bent point (601ab) to cover circular circumference of the fixation shaft (305) and inclined in upward direction from the bent point (601ab) to go over the axle 25 lever (303) and matches with shape and dimensions of the axle lever (303); and
the second bent metal leg (602) molded into the holder (302) from fixed end (602b), the second bent metal leg (602) bends in upward direction upto bent point (602bb) to cover circular circumference of the fixation shaft 30 (305) and bent in downward direction from the bent point (602bb) to go
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below the axle lever (303) and matches with shape and dimensions of the axle lever (303).
3. The gear shift lever assembly (GSLA) (300) as claimed in claim 2, wherein the first bent metal leg (601) and the second bent metal leg (602) are same 5 in dimensions and bent angles.
4. The gear shift lever assembly (GSLA) (300) as claimed in claim 2, wherein the first bent metal leg (601) and the second bent metal leg (602) are mirror image of each other. 10
5. The gear shift lever assembly (GSLA) (300) as claimed in claim 2, wherein free end (601ac) of the first bent metal leg (601) rests on upper surface of a protrusion (307) which extends outwardly away from the holder (302) in 15 direction of the axle lever (303).
6. The gear shift lever assembly (GSLA) (300) as claimed in claim 2, wherein free end (602bc) of the second bent metal leg (602) rests on lower surface of a protrusion (307) which extends outwardly away from the holder (302) in 20 direction of the axle lever (303).
7. The gear shift lever assembly (GSLA) (300) as claimed in claim 2, wherein the first bent metal leg (601), the second bent metal leg (602), the axle lever (303), and the protrusion (307) matches with one another in shape and 25 dimensions and have close tolerances.
8. The gear shift lever assembly (GSLA) (300) as claimed in claim 2, wherein the first bent metal leg (601) has tension in downward direction.
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9. The gear shift lever assembly (GSLA) (300) as claimed in claim 2, wherein the second bent metal leg (602) has tension in upward direction.
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10. The gear shift lever assembly (GSLA) (300) as claimed in claim 2, wherein the bent points (601ab, 602bb) of the first bent metal leg (601) and the second bent metal leg (602) in between the fixation shaft (305) and the axle lever (303) provide close tolerance between the axle lever (303) and the two bent metal legs (601, 602) during select return mechanism.