DESC:TECHNICAL FIELD

Present disclosure in general relates to a field of automobile engineering. Particularly, but not exclusively, the disclosure relates to a transmission assembly for a vehicle. Further, embodiments of the disclosure, discloses a gearbox assembly for the vehicle.

BACKGROUND OF THE DISCLOSURE
Conventionally, vehicles such as but not limiting to passenger vehicles, light duty vehicles, heavy duty vehicles, sports utility vehicles, and multi utility vehicles are equipped with manual transmission. In manual automotive transmission, gears in the gearbox are operated through gearshift lever. The operation of gearshift lever is transferred to shift rails which are used for changing the gears. The shift rails are arranged next to one another in the gearbox housing. Further, a shifter shaft with a shift finger is provided in the gearbox, in which the shift finger engages alternately with shift slots of the shift rails for gear shifting. In such gear box the gearshift lever will be operated by the user or driver when he intends to shift the gear to either higher or lower or reverse gear. For shifting the gear the user has to first disengage clutch from an input shaft, and then move the gear lever to particular gate for selection of the gear. Generally, each gate of the gear box will be provided with two gears, and the gearshift lever will be moved either in forward or backward direction to select the particular gear in the gearbox. Once, the gear is selected the driver will release the clutch pedal to engage the clutch with the input shaft, and thereby engages the output shaft with the input shaft with the help of selected gear. Generally, such gear shifting is called as manual gear shifting, and the transmission is called manual transmission.

Some of the manual transmission vehicles including but not limiting to commercial vehicles are heavy and bulky and require certain amount of skill and technical knowledge for the user or driver to operate the same in the proper manner. Commercial vehicles such as buses and trucks are equipped with engines which generate high amount of torque for high load carrying capacity and thus, there are numerous factors which will affect the performance of the engine and so the vehicle itself. Conventionally, commercial vehicles in the past were not equipped with complex engineered engines or transmission systems and hence requirement of skilled drivers was not necessary. However, with the increase in demand in operating conditions of such vehicles, complex transmission mechanisms have been used in commercial vehicle to cater various needs. Such complex transmission mechanisms demand for higher gear ratio which increase number gears used in the gearbox.
Due to varying demands in the road and manoeuvring conditions, the users shift the gears drastically. As an example, user would abruptly shift the gears from higher gear to the lower gear to control speed of the vehicle, or by mistake. Such improper shifting of gear is called skip shifting of the gears, and this can critically damage the transmission box or gearbox. The term skip shifting used herein above and below is a process in which the user abruptly shifts the gear from a higher gear to a lower gear. During this process, the rotational speed of the clutch increases. In some scenarios, the speed of the clutch increases to maximum threshold speeds or even beyond. This damages the clutch housing and internal components of the transmission box or gearbox. Further, when the user skip shifts and lowers the gear all of a sudden, undesired mechanical stresses are introduced thereby producing high vibrations in transmission system, which may results in transmission box or gearbox failure. Also, during skip shifting, overhauling of components may occur and over a period of time, these components might have to be changed or reworked. The repair works or replacements of such parts are expensive and time consuming as well.
In light of the foregoing discussion, there is a need to develop a mechanism to inhibit skip shifting of gears in the gearbox of the vehicle to overcome the one or more limitations stated above.
SUMMARY OF THE DISCLOSURE

One or more shortcomings of the prior art are overcome by a mechanism and assembly as claimed and additional advantages are provided through the mechanism and assembly as claimed in the present disclosure. Additional features and advantages are realized through the techniques of the present disclosure. Other embodiments and aspects of the disclosure are described in detail herein and are considered a part of the claimed disclosure.

In one non-limiting embodiment of the disclosure a mechanism to inhibit skip shift in a gearbox of a vehicle is disclosed. The mechanism comprises a member which is slidably disposed in gearbox housing. The member comprises a slot of predetermined shape configured to accommodate a projection of a shift finger and at least one first protrusion is configured on a first side of the member. The mechanism comprises at least one first detent configured in the gearbox housing, such that the at least one first detent comprises a pin configured to selectively abut the at least one first protrusion on the member during the gear shifting. Also, the at least one first detent is configured to allow the at least one first protrusion on the member to slide on the pin during shifting of gear from lower gear to higher gear while the pin inhibits the movement of the member during shifting of gear from higher gear to lower gear.

In an embodiment of present disclosure, at least one first protrusion is configured in a wedge shape.

In an embodiment of present disclosure, a contact surface of the pin with the at least one first protrusion is configured in a wedge shape.

In an embodiment of present disclosure, at least one slider pin is provided extending from either sides of the member for guiding the member in the gearbox housing.

In an embodiment of present disclosure, at least one slider pin comprises of at least one flange. Further, at least one first resilient member is disposed between either sides of the member and the at least one flange provided on the at least one slider pin.

In an embodiment of present disclosure, the member comprises of at least one second protrusion in a second side.

In an embodiment of present disclosure, a second detent is configured between the gearbox housing and a second protrusion of the member. The second detent is configured to apply selection resisting force on the member during shifting of gear from lower gear to higher gear and selection assisting force on the member during shifting of gear from higher gear to lower gear.

In an embodiment of present disclosure, the pin in the at least one first detent is actuated by a second resilient member.

In an embodiment of present disclosure, the slot is configured in substantially “T-shape”. The “T-shape” slot comprises a first portion extending in axial direction (A-A) of the shifter shaft, and a second portion extending in transverse direction (B-B) of the shifter shaft, and the second portion is adjacent to the first portion.

In an embodiment of present disclosure, the projection on the shift finger is configured to reside in a first portion of a “T-shape” slot when the member is inhibited by the at least one first detent. The at least one first protrusion is configured to offset from the pin of the at least one first detent, when the projection is operated in transverse direction (B-B) of the shifter shaft in a second portion of a “T-slot”. Further, the second detent is configured to push the member in axial direction (A-A) of the shifter shaft when the at least one first protrusion is offset from the pin of the at least one first detent.

In another non-limiting embodiment of the disclosure, a shifter assembly for a gearbox of a vehicle is disclosed. The assembly comprises a shifter shaft mounted in a gearbox housing, wherein the shifter shaft is coupled to a shift lever and is adapted to make rotary and translatory movement in the gearbox housing for gate selection and gear shifting. A shift finger mounted on the shifter shaft, wherein the shift finger comprises of a projection. The shifter assembly also comprises a mechanism configured in the gearbox housing to inhibit skip shift of gears. The mechanism comprises a member slidably disposed in a gearbox housing, wherein the member comprises a slot of predetermined shape configured to accommodate the projection of the shift finger and at least one first protrusion configured in a first side of the member. The mechanism also comprises at least one first detent configured in the gearbox housing, wherein the at least one first detent comprises a pin configured to selectively abut the at least one first protrusion during the gear shifting. Further, the at least one first detent is configured to allow the at least one first protrusion to slide on the pin during shifting of gear from lower gear to higher gear, and inhibit the movement of the member during shifting of gear from higher gear to lower gear.

In an embodiment of present disclosure, the member is positioned on a guide way in the gearbox housing.

In an embodiment of present disclosure, a vehicle comprising a mechanism to inhibit skip shift in a gearbox of a vehicle.

It is to be understood that the aspects and embodiments of the disclosure described above may be used in any combination with each other. Several of the aspects and embodiments may be combined together to form a further embodiment of the disclosure.

The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

The novel features and characteristic of the disclosure are set forth in the appended claims. The disclosure itself, however, as well as a preferred mode of use, further objectives and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying figures. One or more embodiments are now described, by way of example only, with reference to the accompanying figures wherein like reference numerals represent like elements and in which:

Figure 1 illustrates a perspective view of a gearbox of a vehicle according to an exemplary embodiment of the present disclosure.
Figure 2 illustrates perspective view of the top cover assembly used in gearbox according to an exemplary embodiment of the present disclosure.
Figure 3 illustrates sectional view of the top cover assembly of FIG. 2.
Figure 4 illustrates top view of the member incorporated in the top cover assembly of FIG. 2, according to an exemplary embodiment of the present disclosure.
Figure 5 illustrates a perspective view of shift finger of shifter assembly of the gearbox according to an exemplary embodiment of the present disclosure.
Figure 6 illustrates a perspective view of first detent incorporated in the gearbox housing as an exemplary embodiment of the present disclosure.
Figure 7 illustrates perspective view of top cover assembly of the gearbox showing a mechanism to inhibit the skip shift of gears in the gearbox according to an exemplary embodiment of the present disclosure.
Figure 8 illustrates top view of the top cover mechanism showing position of the mechanism to inhibit skip shift with gear at Neutral position according to an exemplary embodiment of the present disclosure.
Figure 9 illustrates perspective view of the top cover assembly of the gearbox showing first detent and the second detent in working according to an exemplary embodiment of the present disclosure.
Figure 10a illustrates top view of the top cover mechanism showing position of the projection to inhibit skip shift during actuation of higher gears according to an exemplary embodiment of the present disclosure.
Figure 10b illustrates top view of the top cover mechanism of FIG. 10a showing position of projection on the shift lever to actuate fifth gear according to an exemplary embodiment of the present disclosure.
Figure 10c illustrates top view top cover mechanism showing position of the mechanism to inhibit skip shift during shifting of gear to neutral position from fifth gear according to an exemplary embodiment of the present disclosure.
Figure 10d illustrates top view of the top cover mechanism showing position of the mechanism to inhibit skip shift ensuring the member engages into moderate gear [third gear] from neutral position according to an exemplary embodiment of the present disclosure.
Figure 11 illustrates a top view of top cover mechanism showing displacement of member away from the first detent according to an exemplary embodiment of the present disclosure.
The figures depict embodiments of the disclosure for purposes of illustration only. One skilled in the art will readily recognize from the following description that alternative embodiments of the mechanism and assembly illustrated herein may be employed without departing from the principles of the disclosure described herein.

DETAILED DESCRIPTION

While the embodiments in the disclosure are subject to various modifications and alternative forms, specific embodiment thereof has been shown by way of example in the figures and will be described below. It should be understood, however that it is not intended to limit the disclosure to the particular forms disclosed, but on the contrary, the disclosure is to cover all modifications, equivalents, and alternative falling within the scope of the disclosure.

The terms “comprises”, “comprising”, or any other variations thereof used in the disclosure, are intended to cover a non-exclusive inclusion, such that a device, assembly, mechanism, system, method that comprises a list of components does not include only those components but may include other components not expressly listed or inherent to such system, or assembly, or device. In other words, one or more elements in a system proceeded by “comprises… a” does not, without more constraints, preclude the existence of other elements or additional elements in the system or mechanism.

In order to overcome one or more limitations stated in the background, the present disclosure provides a mechanism which may be employed in a gearbox of the vehicle to inhibit skip shift of gears. The mechanism broadly comprises a member of predetermined shape is slidably disposed in a gearbox housing. The member is supported by one or more slider pins in the gearbox housing. The one or more slider pins are configured to slide on a guide way provisioned in the housing to facilitate movement of the member in the gearbox housing. The member comprises a slot of predetermined shape configured to accommodate a projection of a shift finger, such that the member moves relative to the movement of shift finger in the gearbox housing. The member also comprises at least one first protrusion configured on a first side of the member. The mechanism also comprises at least one first detent is configured in the gearbox housing. The at least one first detent comprises a pin configured to selectively abut the at least one first protrusion on the member during the gear shifting. Also, the at least one first detent is configured to allow the at least one first protrusion on the member to slide on the pin during shifting of gear from lower gear to higher gear while the pin inhibits the movement of the member during shifting of gear from higher gear to lower gear. This avoids abrupt shifting of gears from higher gear to the lower gear in the gearbox, thereby reduces effect on the clutch and other parts of the gearbox.

Embodiments of the disclosure are described in the following paragraphs with reference to Figures 1 to 13. In the figures, the same element or elements which have same functions are indicated by the same reference signs. It is to be noted that, the vehicle is not illustrated in the figures for the purpose of simplicity. One skilled in the art would appreciate that the mechanisms and assembly as disclosed in the present disclosure can be used in any vehicle including but not liming to passenger car, heavy vehicles, light duty vehicles or any other vehicle.

Figure 1 is an exemplary embodiment of the present disclosure which illustrates a perspective view of the gearbox (25). The gearbox (25) is used in transmission layout [not shown] of the vehicle to transmit power generated by an engine to the wheels depending on the requirement. As it is known the gearbox (25) generally comprises an input shaft (27) connectable to an engine crank shaft and output shaft (28) connectable to a transmission assembly such as differential or drive shafts. The input shaft (27) and the output shafts are provided with a plurality driving and driven gears [not shown] housed in a gearbox housing (22). The driven gears on the output shaft are engaged with the corresponding driving gear in the inputs shaft (27) by one or more clutch mechanisms [not shown]. The gearbox (25) also comprises a top cover assembly (500) which is coupled to a gear lever [not shown]. The top cover assembly (500) is adapted to shift or change the gears or gates in the gearbox (25) when the user actuates the gear lever [not shown in the figures] in order to shift from one gear to another.

In an embodiment of the present disclosure, the orientations of the top cover assembly (500) on the gearbox (25) need not be limited as illustrated. The orientation can be designed and assembled according to the requirements of the vehicle such as whether the vehicle is a left hand driven or right hand driven or any similar manner that serves the purpose.
The top cover assembly (500) [shown in FIG.2] comprises an upper cover (1a) which is configured to house skip shift inhibition mechanism (100) [see Figure 7] and gear shift mechanism [not shown in figures]. A lower cover (1b) is provided in the top cover assembly (500) to house a shifter shaft (9) connected to a shift lever (3). Further, the other end of the shift lever (3) is linked to a gear lever for operating or changing or shifting of gears. A rubber bellow (2) is provided at the interface of shift lever (3) and lower housing (1b) to ensure adequate protection to shifter shaft (9) from air and dust in the vehicle. The lower cover (1b) of the top cover assembly (500) can be removably attached to the gearbox housing (22), through a suitable joining mechanism such as but not limiting to fastening, welding or any other method that serves the purpose.
Figure 3 is an exemplary embodiment of the disclosure which illustrates front sectional view of the top cover assembly (500). As shown in Figure 3, the top cover assembly (500) houses a shifter shaft (9) mounted in the lower cover (1b) and is connected to the shift lever (3) through a link. Other end of the shifter shaft (9) is equipped with a plurality of springs (24) to apply selection resisting and assisting force during gear shifting. The shifter shaft (9) is sealed within the lower cover (1b) with a mechanical seal (23), to restrict entry of foreign particles into the assembly (500). The shifter shaft (9) actuates linearly within the lower cover (1b) for shifting of gears and a shift finger (5) is sandwiched between a pair of interlock finger (6) is connected to the shifter shaft (9) with a pin insert (26). In an embodiment, the pin insert (26) can be a dowel pin, a fastener assembly, dowel joint or any other mechanical component that serves the purpose of fixing and enabling the shift finger (5) to rotate with the shifter shaft (9).
The upper cover (1a) of the top cover assembly is configured to accommodate the mechanism to inhibit the skip shift in the gearbox (25). The mechanism broadly comprises a member (4), at least one first detent (7) and a second detent (10).
Figure 4 is an exemplary embodiment of the disclosure which illustrates top view of the member (4) incorporated in the top cover assembly (500). The member (4) will be slidably disposed in the top cover assembly (500) [in-turn in the gearbox housing (22)] with the help of at least one slider pins (15). The member (4) comprises a slot (14) of predetermined shape which accommodates a projection (20) provided on the shift finger (9). In an embodiment of the disclosure, the slot (14) is configured in substantially “T” shape, and comprises a first portion (FP) which extends along the axial direction (A-A) of the shifter shaft (9), and second portion (SP) adjacent to the first portion (FP). The second portion (SP) of the slot (14) extends in transverse direction (B-B) of the shifter shaft (9). The projection (20) is configured to reside in at least one of first portion (FP) and the second portion (SP) of the slot (14) during gear shifting. The member (4) also comprises at least one first protrusion (12) and a second protrusion (13) on first and second sides of the member (4) respectively. In an embodiment, the at least one first protrusion (12) is configured in a wedge shape. However, one should not construe a wedge shape as a limitation as one can provide any other shape that serves the purpose.
As shown in FIG. 4 the at least one slider pin (15) is provided on either side of the member (4) to slidably move the member (4) on the guide ways (21) of the gearbox housing (22). Further, each of the at least one slider pin (15) comprises at least one flange (19), and a first resilient member (16) is accommodated between the sides of the member (4) and at least one flange (19). The first resilient member (16) is configured to be compressed and relaxed during transverse movement of the member (4) due to action of projection (20). On actuation of the gear lever, the shift lever (3) actuates shift finger (5) to change or shift the gear and simultaneously the projection (20) moves the member (4) in the guide ways (21). The movement of the member (4) can be along the axial direction (A-A) or transverse direction (B-B) or both.
In an embodiment, the projection (20) moves to a first portion (FP) of the slot (14) when the member (4) is to be moved either in axial direction (A-A) or both axial direction (A-A) and transverse direction (B-B).
In an embodiment, the projection (20) moves to a second portion (SP) of the slot (14) when the member (4) is to be moved in transverse direction (B-B).
Figure 5 is an exemplary embodiment of the disclosure which illustrates perspective view of the shift finger (5) incorporated in the top cover assembly (500). The shift finger (5) is designed such that a projection (20) extends from the top portion of the shift finger (5). The projection (20) can be accommodated within the slot (14) of the member (4). The shift finger (5) is fixed on the shifter shaft (9) a suitable mechanism. In an embodiment of the disclosure, the shift finger (5) is fixed on the shifter shaft (9) using the pin insert (26). Thus, the shift finger (5) is enabled to move and twist along the shifter shaft (9) during changing or shifting of gears.
Figure 6 illustrates a perspective view of the at least one first detent (7) incorporated in the top cover assembly (500). The first detent (7) comprises housing configurable in the top cover assembly (500)/gearbox housing. The housing (29) comprises a through hole configured to accommodate a pin (8). The pin (8) is loaded with a second resilient member (17) and is enclosed by an end cap (30) of the housing (29). The pin (8) is configured such that the second end of the pin (8) reciprocates in and out of the housing (29) due to action of the second resilient member (17). In an embodiment of the disclosure, the second resilient member (17) is a coil spring, and is positioned in housing (29) such that, the second end of the pin (8) will protrude completely out of the housing (29) when the second resilient member (17) is extended state. Further, the second end of the pin (8) is configured in a wedge shape, such that that the at least one first protrusion (12) of the member (4) will slide on the pin (8) during shifting of gear from lower gear to moderate gear, and the member (4) will be inhibited from movement during skip-down shifting i.e. while changing or shifting directly from higher gear to lower gear.
In an embodiment, the second resilient member (17) is actuated when the wedge shape of the pin (8) is comes in contact with the wedge shape of at least one first protrusion (12) and the gear can be shifted from lower gear to moderate gear. This enables the member (4) to slide over the pin (8) thereby allows the movement of member (4). During this condition, the second resilient member (17) will be compressed by the member (4). Once, the member (4) surpasses the pin (8), the second resilient member (17) expand and push the pin (8) to protrude out of the housing.
Figure 7 is an exemplary embodiment of the disclosure, which illustrates perspective view of the top cover assembly (500) on the gearbox (25). As shown in the Figure 7, the top cover assembly (500) houses a mechanism (100) to inhibit skip shift of gears. The mechanism comprises a member (4) slidably disposed in a top cover assembly (500). The member (4) is supported by at least one slider pin (11) in the top cover assembly (500). The at least one slider pin (11) is configured to slide on a guide way (21) provisioned in the top cover assembly (500) to facilitate movement of the member (4) in the top cover assembly (500). The member (4) comprises a slot (14) of predetermined shape configured to accommodate a projection (20) of a shift finger (5), such that the member (4) moves relative to the movement of shift finger (5) in the gearbox housing (22). The member (4) also comprises at least one first protrusion (12) configured on a first side of the member (4). The mechanism (100) also comprises at least one first detent (7) configured in the top cover assembly (500). The at least one first detent (7) comprises a pin (8) configured to selectively abut the at least one first protrusion (12) on the member (4) during gear shifting. Also, the at least one first detent (7) is configured to allow the at least one first protrusion (12) on the member (4) to slide on the pin (8) during shifting of gear from lower gear to moderate gear while the pin (8) inhibits the movement of the member (4) during shifting of gear from higher gear to lower gear. This avoids abrupt shifting of gears from higher gear to the lower gear in the gearbox (25), thereby reduces effect on the clutch and other parts of the gearbox (25). It is to be noted that the words gearbox assembly and the top cover assembly are interchangeably used. One should not consider the same as two different aspects, as the top cover assembly is a part of gearbox housing and is mounted on the gearbox housing.
The member (4) also comprises a second protrusion (13) on the second side, and at least one second detent (10) is configured between the second protrusion (13) and a wall of the top cover assembly (500). The second detent (10) is configured to the third resilient member (18), so that the second detent (10) triggers the member (4) via second protrusion (13) to move along axial direction (A-A).
In an embodiment, during down-shift of the gear i.e. shifting from higher gear, third resilient member (17) triggers the second detent (10) to move the member (4) instantly in order to provide minimal time for the user, if attempted to skip shift, and hence, at least one first protrusion on the member (4) encounters the at least one first detent (7). The pin (8) of at least one first detent (7) locks with the at least one first protrusion (12) on the member (4) to avoid further movement of the member (4), thereby avoiding skip shifting of gears. When at least one first protrusion (12) on the member (4) is locked by the pin (8), the gear lever is restricted from moving towards lower gears and cannot easily surpass the pin (8) thereby the user is forced to engage to any of the moderate gears.
Figure 8 is an exemplary embodiment of the disclosure which illustrates top view of the mechanism (100) for inhibiting skip shift of gears for a 7 speed gearbox [not shown].
In the 7 speed gearbox (25), the gear arrangement will be as follows: in the neutral position of the gear lever at user end will be unaltered and the member (4) will be in its initial position [shown in FIG. 8]. The higher gears i.e. 6th gear and 5th gear are arranged towards second end (SE) of the member (4), so that the member (4) should be moved in axial direction (A-A) from its initial position and then moved in transverse direction (B-B) to engage to either of the gears. Further, the moderate gears i.e. 4th gear and 3rd gear are arranged adjacent to initial position of the member (4) and either of the gears is engaged by moving the member (4) in transverse direction (B-B). Lastly, the lower gears i.e. 2nd gear and 1st gear are positioned towards first end (FE) of the member (4), and the member (4) will be moved forward from its initial position in axial direction (A-A) and then moved in transverse direction (B-B) to engage either of the gears. The gear lever will be provided with an inverted mirror image of the same for the user reference. Also, during shifting of gear from one gear level to another, the gear lever as well as the shift finger (5) should pass via neutral position to ensure smooth gear shift.
In the neutral position, the projection (20) on the shift finger (5) is configured to reside in the second portion (SP) of the slot (14) in the member (4). The member (4) will be configured such that at least one first protrusion (12) will be abutting the pin (8) of the at least one first detent (7). When the user operate the gear lever to select the lower gears i.e. 1st or 2nd gear, the projection (20) will move to the first portion (FP) of the slot (14) towards the first end (FE) of the member (4) and the member (4) will be moved forward with respect to axial axis (A-A), and can be operated in transverse direction (B-B) to select the lower gear. Further, while shifting of gears from lower gear to moderate gears, at least one first protrusion (12) will slide on the pin (8) and allow the movement of the member (4). The projection (20) will move in the first portion (FP) of the slot (14) towards the second end (SE) of the member ((4) and the member (4) will be moved back with respect to axial axis (A-A), and can be operated in transverse direction (B-B) to select the moderate gear.
In an embodiment, the projection (20) in the slot (14) is initially at rest or at the intersection of axis of axial direction (A-A) and axis of transverse direction (B-B) and the gear is in Neutral position.
Referring to Figure 9, which illustrate perspective view of at least one first detent (7) and the second detent (10) in working condition. During shifting of gear from moderate gear to higher gear, the projection (20) pushes the member (4) in axial direction (A-A) and the second protrusion (13) at second end (SE) of the member (4) drives the second detent (10) in order to compress the third resilient member (18). This enables the member (4) to move in axial direction (A-A) and thus, to engage the required higher gear. Meanwhile, at least one first detent (7) is idle and second resilient (17) is relaxed.
Now referring to Figures 10a and 10b, which illustrates movement of member (4) for shifting to higher gears. Considering an example, wherein the user is currently in moderate gear i.e. either 4th gear or 3rd gear and needs to up-shift the gear to higher level. The user brings back the lever to Neutral position before shifting to higher gear. In the gearbox (25), to reach higher gears, the member (4) should be moved towards second end (SE) of the member (16) from initial position in axial direction (A-A) by the projection (20). The transverse axis (B-B) shifts to transverse axis (B’-B’). Further, to engage higher gear i.e. either of 5th gear or 6th gear, the projection (20) moves into second portion (SP) of the “T” slot (14), and moves in traverse direction (B’-B’) due to rotation of the shifter shaft to select the required higher gear. As illustrated in Figure 10b, to engage 5th gear, the projection (20) moves below axial direction axis (A-A) and thus, the gear is engaged.
In an embodiment, to engage 5th gear, the first resilient member (16) configured between at least one slider pin (15) and at least one flange (19) will be compressed due to action of the projection (20) in the second portion (SP) of the “T” slot (14) and the counter part is relaxed.
In an embodiment, to engage 6th gear, the first resilient member (16) configured between at least one slider pin (15) and at least one flange (19) will be compressed due to action of the projection (20) in the second portion (SP) of the “T” slot (14) and the counter part is relaxed.
Referring now to Figures 10c and 10d, which illustrates movement of member (4) during shifting from higher gears to lower gears. The skip-shifting of the gear happens when the user tries to move the gears abruptly from higher gears to lower gears without shifting to moderate gears. The mechanism (100) proposed prevents such skip shifting by inhibiting the movement of the member (4) to move towards lower gear. As shown in FIG. 10c, when the user shifts the gear directly from higher to lower gear, the projection (20) moves back in transverse direction axis (B’-B’) and then is moved along axial axis (A-A) to reach the first portion (FP) of the “T” slot (14) due to the action of second detent (10). When the projection (20) reaches the Neutral position, third resilient member (18) triggers second detent (10) to push the member (4) forward along with the projection (20), thereby ensuring pin (8) of at least one first detent (7) is locked with at least one first protrusion (12) of the member (4). Thus, the user is inhibited to move the member (4) forward to reach for lower gears and is forced to shift to either of the moderate gears. This gives an indication to the user to shift the gear to moderate gear.
When the gear lever is moved to engage 3rd gear, the first resilient member (16) configured between at least one slider pin (15) will compressed due to action of the projection (20) in first portion (FP) of “T” slot (14) and along the transverse axis (B-B), while the counter part is relaxed, and the member (4) will move offset from the first detent (7) Similarly, when the user moves the gear lever to shift to engage 4th gear, the first resilient member (16) configured between at least one slider pin (15) and at least one flange (19), will be compressed due to action of the projection (20) in first portion (FP) of the “T” slot (14) along the transverse axis (B-B), while the counter part is relaxed, and the member (4) will move offset from the first detent (7).
In an embodiment, during engagement of either of moderate gears, the member (4) is pushed by the second detent (10) which moves the member (4) offset from at least one first detent. During offset movement of the member (4), the second detent (10) pushes the member (4) forward which is in turn is triggered by the third resilient member (18) due to spring action. Due to this push by third resilient member (18), the member (4) is moved along the axial direction (A-A) by a predetermined value. Also, the third resilient member (18) is completely relaxed and is free from compression and the moderate gears can be engaged. Further, the user is now allowed to shift to lower gears.
In an embodiment, the predetermined value by which the member (4) is displaced is in the range of about 5mm to 13mm.
Figure 11 is an exemplary embodiment which illustrate the at least one first protrusion (12) on the member (4) being displaced away from the pin (8) of at least one first detent (7). The projection (20) in the first portion (FP) of “T” slot (14) and first end (FE) of the member (4), is moved forward along the axial axis (A-A) and then moved in transverse direction (B-B) to actuate the lower gears. Further, when projection (20) is moved to its initial position, the pin (8) of the at least one first detent (7) will be compressed and allow the at least one first protrusion (12) slide on the same. This ensures, smooth movement of the member (4) without any inhibition during shifting of gears from lower gear to higher gear.
EQUIVALENTS

With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity.

It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes but is not limited to,” etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases “at least one” and “one or more” to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim recitation to inventions containing only one such recitation, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an” (e.g., “a” and/or “an” should typically be interpreted to mean “at least one” or “one or more”); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of “two recitations,” without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to “at least one of A, B, and C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, and C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances where a convention analogous to “at least one of A, B, or C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, or C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase “A or B” will be understood to include the possibilities of “A” or “B” or “A and B.”

In addition, where features or aspects of the disclosure are described in terms of Markush groups, those skilled in the art will recognize that the disclosure is also thereby described in terms of any individual member or subgroup of members of the Markush group.

While various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.

REFERAL NUMERALS:
PARTICULARS NUMBER
Upper cover 1a
Lower cover 1b
Rubber bellow 2
Shift lever 3
Member 4
Shift finger 5
Interlock finger 6
First detent 7
Pin 8
Shifter shaft 9
Second detent 10
Slider pin 11
First protrusion 12
Second protrusion 13
Slot 14
Slider pin 15
First resilient member 16
Second resilient member 17
Third resilient member 18
Flange 19
Projection 20
Guide ways 21
Gearbox housing 22
Mechanical seal 23
Plurality of springs 24
Gearbox 25
Pin insert 26
Input shaft 27
Output shaft 28
First detent housing 29
End cap 30
Mechanism 100
Top cover assembly 500
First portion FP
Second portion SP
First end FE
Second end SE
,CLAIMS:WE CLAIM:
1. A mechanism (100) to inhibit skip shift in a gearbox (25) of a vehicle, the mechanism (100) comprising:
a member (4) slidably disposed in a gearbox housing (22), wherein the member (4) comprises:
a slot (14) of predetermined shape configured to accommodate a projection (20) of a shift finger (5); and
at least one first protrusion (12) configured in a first side of the member (4); and
at least one first detent (7) configured in the gearbox housing (22), wherein the at least one first detent (7) comprises a pin (8) configured to selectively abut the at least one first protrusion (12) during the gear shifting,
wherein, the at least one first detent (7) is configured to allow the at least one first protrusion (12) to slide on the pin (8) during shifting of gear from lower gear to higher gear, and inhibit the movement of the member (4) during shifting of gear from higher gear to lower gear.

2. The mechanism (100) as claimed in claim 1, wherein the at least one first protrusion (12) is configured in a wedge shape.

3. The mechanism (100) as claimed in claim 1, wherein a contact surface of the pin (8) with the at least one first protrusion (12) is configured in a wedge shape.

4. The mechanism (100) as claimed in claim 1, comprises at least one slider pin (15) extending from either sides of the member (4) for guiding the member (4) in the gearbox housing (22).

5. The mechanism (100) as claimed in claim 4, wherein the at least one slider pin (15) comprises at least one flange (19).

6. The mechanism (100) as claimed in claim 5, comprises at least one first resilient member (16) disposed between either sides of the member (4) and the at least one flange (19) provided on the at least one slider pin (15).

7. The mechanism (100) as claimed in claim 1, wherein the member (4) comprises at least one second protrusion (13) in a second side.

8. The mechanism (100) as claimed in claim 1, comprises a second detent (10) configured between the gearbox housing (22) and a second protrusion (13) of the member (4).

9. The mechanism (100) as claimed in claim 8, wherein the second detent (10) is configured to apply selection resisting force on the member (4) during shifting of gear from lower gear to higher gear and selection assisting force on the member (4) during shifting of gear from higher gear to lower gear.

10. The mechanism (100) as claimed in claim 1, wherein the pin (8) in the at least one first detent (7) is actuated by a second resilient member (17).

11. The mechanism (100) as claimed in claim 1, wherein the slot (14) is configured in substantially “T-shape”.

12. The mechanism (100) as claimed in claim 11, wherein the “T-shape” slot (14) comprises:
a first portion (FP) extending in axial direction (A-A) of the shifter shaft (9); and
a second portion (SP) extending in transverse direction (B-B) of the shifter shaft (9), wherein the second portion (SP) is adjacent to the first portion (FP).

13. The mechanism (100) as claimed in claim 1, wherein the projection (20) on the shift finger (5) is configured to reside in a first portion (FP) of a “T-shape” slot (14) when the member (4) is inhibited by the at least one first detent (7).

14. The mechanism as claimed in claim 1, wherein the at least one first protrusion (12) is configured to offset from the pin (8) of the at least one first detent (7), when the projection (20) is operated in transverse direction (B-B) of the shifter shaft (9) in a second portion (SP) of a “T-slot”.

15. The mechanism as claimed in claim 14, wherein the second detent (10) is configured to push the member (4) in axial direction (A-A) of the shifter shaft (9) when the at least one first protrusion (12) is offset from the pin (8) of the at least one first detent (7).

16. A shifter assembly (500) for a gearbox of a vehicle, the assembly (500) comprising:
a shifter shaft (9) mounted in a gearbox housing (22), wherein the shifter shaft (9) is coupled to a shift lever (3) and is adapted to make rotary and translatory movement in the gearbox housing (22) for gate selection and gear shifting;
a shift finger (4) mounted on the shifter shaft (9), wherein the shift finger (4) comprises a projection (20); and
a mechanism (100) configured in the gearbox housing (22) to inhibit skip shift of gears, the mechanism (100) comprising:
a member (4) slidably disposed in a gearbox housing (22), wherein the member (4) comprises:
slot (14) of predetermined shape configured to accommodate the projection (20) of the shift finger (4); and
at least one first protrusion (12) configured in a first side of the member (4); and
at least one first detent (7) configured in the gearbox housing (22), wherein the at least one first detent (7) comprises a pin (8) configured to selectively abut the at least one first protrusion (12) during the gear shifting,
wherein, the at least one first detent (7) is configured to allow the at least one first protrusion (12) to slide on the pin (8) during shifting of gear from lower gear to higher gear, and inhibit the movement of the member (4) during shifting of gear from higher gear to lower gear.
17. The assembly (500) as claimed in claim 16, wherein the member (4) is positioned on a guide way (16) in the gearbox housing (22).

18. The assembly (500) as claimed in claim 16, wherein the member (4) comprises at least one slider pin (15) extending from either sides for guiding the member (4) in the gearbox housing (22).

19. The assembly (500) as claimed in claim 16, wherein the pin (8) in the at least one first detent (7) is spring loaded by a second resilient member (17).
20. The assembly (500) as claimed in claim 16, comprises a second detent (10) between the gearbox housing (22) and a second protrusion (13) of the member (4) is actuated by a third resilient member (18).

21. The assembly (500) as claimed in claim 20, wherein the second detent (10) is configured to apply selection resisting force on the member (4) during shifting of gear from lower gear to higher gear and selection assisting force on the member (4) during shifting of gear from higher gear to lower gear.

22. A vehicle comprising a mechanism (100) to inhibit skip shift in a gearbox (25) of a vehicle as claimed in claim 1.