Description:FIELD OF THE INVENTION
[001] The present invention relates to a gearshift assembly. More particularly, the present invention relates to a gearshift assembly for a vehicle.

BACKGROUND OF THE INVENTION
[002] Conventionally, in saddle type vehicles, particularly motorcycle type vehicles, the gearshift operation is performed by the user using their foot. In existing vehicles, the rider footrest and gear shift pedal positions are fixed. For the gear shifting operation, the gear shift pedal is connected to gear shift shaft of the engine with a fixed length four bar linkage mechanism. The rider actuates the gear shift shaft of engine by actuating this four bar linkage mechanism. Any change in the positions of rider footrest, gear shift pedal due to different ergonomical requirement needs complete re-design of four bar linkage mechanism.
[003] However, in modern vehicles, there is an increased demand and requirement for providing adjustable foot pegs or adjustable gear shift pedals which can be dynamically adjusted in accordance with the ergonomic requirements of the rider. In existing solutions for allowing provision of adjustable foot pegs and adjustable gear shift pedals, there has been a shift from conventional four bar linkage mechanisms to shift by wire technologies. Shift by wire systems employ electrical or electronic connections that replace the mechanical connection between the user's gearshift mechanism and the transmission. Since, these systems eliminate the requirement of the four bar linkage mechanism, the gear shift pedal as well as the foot pegs can be adjusted.
[004] However, in gearshift by wire configurations, there is no positive feedback of the gearshift process to user. Due to lack of positive feedback to the user, there occur two major problem scenarios. The first being that when the user intends to shift the gear and operates the pedal, the gear gets shifted but the user does not feel that the gear has shifted or changed. The second problem scenario occurs when the user operates the pedal but the gear does not get shifted, the user may still feel that the gear has been shifted/changed.
[005] Thus, there is a need in the art for a gearshift assembly for a vehicle which addresses at least the aforementioned problems.

SUMMARY OF THE INVENTION
[006] In one aspect, the present invention relates to a gearshift assembly for a vehicle. The gearshift assembly has a lever configured to be operated by a user. The gearshift assembly further has a central assembly configured to be engaged with the lever. An upper assembly is configured to alternately rotate and engage with the central assembly for at least one of a gear change operation or generating a sound for notifying the rider of the gear change. Further, a lower assembly is configured to alternately rotate and engage with the central assembly for at least one of a gear change operation and generating a sound for notifying the rider of the gear change.
[007] In an embodiment of the invention, the central assembly has a rotary shaft is configured to rotatably provided within a casing. A central cam is rotatably provided on the rotary shaft. The central cam has a pin protruding radially outward and the pin is configured to be engaged with the lever. The central cam has a first set of helical teeth and a second set of helical teeth.
[008] In a further embodiment of the invention, the upper assembly has an upper cam configured to be selectively engaged with the rotary shaft. The upper cam has a third set of helical teeth configured to be alternately engaged and rotated by the first set of helical teeth, wherein rotating of the third set of helical teeth causes rotational movement of the upper cam, thereby rotating the rotary shaft for a gear change operation, and the engaging of third set of helical teeth with the first set of helical teeth generates a sound for notifying the rider of the gear change.
[009] In a further embodiment of the invention, the lower assembly has a lower cam that is configured to be selectively engaged with the rotary shaft . The lower cam has having a fourth set of helical teeth configured to be alternately engaged and rotated by the second set of helical teeth, wherein rotating of the fourth set of helical teeth causes rotational movement of the lower cam, thereby rotating the rotary shaft for the gear change operation, and wherein the engaging of the fourth set of helical teeth with the second set of helical teeth generates a sound for notifying the rider of the gear change.
[010] In an embodiment of the invention, upward movement of the central cam causes rotating of the third set of helical teeth and rotational movement of the upper cam, thereby rotating the rotary shaft for an upshift gear change operation.
[011] In another embodiment of the invention, downward movement of the central cam causes rotating of the fourth set of helical teeth and rotational movement of the lower cam, thereby rotating the rotary shaft for a downshift gear change operation, wherein the lower cam is configured to rotate in an opposite direction to a direction of rotation of the upper cam.
[012] In a further embodiment of the invention, the casing is configured to house the central cam, the upper cam and the lower cam, and further the casing has a cylindrical profile.
[013] In a further embodiment of the invention, the casing has a casing upper having a set of upper helical teeth, and a casing lower having a set of lower helical teeth. The set of upper helical teeth are configured to engage with the third set of helical teeth of the upper cam for restricting the rotational movement of the upper cam and generating a sound. The set of lower helical teeth are configured to engage with the fourth set of helical teeth of the lower cam for restricting the rotational movement of the lower cam and generating a sound.
[014] In a further embodiment of the invention, the gearshift assembly has a first spring provided between the casing and the upper cam. The first spring is configured to resist the translational movement of the upper cam within the casing.
[015] In a further embodiment of the invention, the gearshift assembly has a second spring provided between the casing and the lower cam. The second spring is configured to resist the translational movement of the lower cam within the casing.
[016] In a further embodiment of the invention, the gearshift assembly has a motion sensor configured to sense the rotation of the rotary shaft. The motion sensor is in communication with a control unit for activating a motor for performing the gear change operation.
[017] In a further embodiment of the invention, an upper end of the rotary shaft has an upper protrusion, and the upper cam has an upper recess. The upper protrusion is configured to engage with the upper recess for transmitting the rotational motion of the upper cam to the rotary shaft.
[018] In a further embodiment of the invention, a lower end of the rotary shaft has a lower protrusion, and the lower cam has a lower recess. The lower protrusion is configured to engage with the lower recess, for transmitting the rotational motion of the lower cam to the rotary shaft.
[019] In another aspect, the present invention relates to a method for a gear change operation. The method has the steps of: operating a lever by a user; moving, a central assembly by operation of the lever for engaging the central assembly with an upper assembly or a lower assembly; alternately engaging and rotating the upper assembly with the central assembly for at least one of a gear change operation and generating a sound for notifying the rider of the gear change; or alternately engaging and rotating the lower assembly with the central assembly for at least one of a gear change operation and generating a sound for notifying the rider of the gear change.
[020] In a further embodiment of the invention, the method has the steps of: operating a lever by a user; moving, a central cam of the central assembly by operation of the lever through a pin for engaging the central cam with an upper cam of the upper assembly or a lower cam of the lower assembly.
[021] In a further embodiment of the invention, the method has the step of alternately engaging and rotating a third set of helical teeth of the upper cam by a first set of helical teeth of the central cam, wherein rotating of the third set of helical teeth causes rotational movement of the upper cam, thereby rotating a rotary shaft for a gear change operation, and wherein the engaging of third set of helical teeth with the first set of helical teeth generates a sound for notifying the rider of the gear change.
[022] In a further embodiment of the invention, the method has the step of alternately engaging and rotating a fourth set of helical teeth of the lower cam by a second set of helical teeth of the central cam, wherein rotating of the fourth set of helical teeth causes rotational movement of the lower cam, thereby rotating the rotary shaft for the gear change operation, and wherein the engaging of the fourth set of helical teeth with the second set of helical teeth generates a sound for notifying the rider of the gear change.
[023] In an embodiment of the invention, the method further has the steps of: moving, the central cam in an upward direction by operation of the lever causing the rotation of third set of helical teeth; and rotating the upper cam, causing rotation of the rotary shaft for an upshift gear change operation.
[024] In a further embodiment of the invention, the method further has the steps of: moving, the central cam in a downward direction by operation of the lever causing the rotation of fourth set of helical teeth; and rotating the lower cam, causing rotation of the rotary shaft for a downshift gear change operation.
[025] In a further embodiment of the invention, the method further has the steps of: engaging a set of upper helical teeth on a casing upper with the third set of helical teeth for restricting the rotational movement of the upper cam and generating a sound: and engaging a set of lower helical teeth on a casing lower with the fourth set of helical teeth for restricting the rotational movement of the lower cam for restricting the movement of the lower cam and generating a sound.
[026] In an embodiment of the invention, the method further has the steps of: sensing, by a motion sensor, rotation of the rotary shaft; and activating, by a control unit in communication with the motion sensor, a motor for performing a gearshift operation.

BRIEF DESCRIPTION OF THE DRAWINGS
[027] Reference will be made to embodiments of the invention, examples of which may be illustrated in accompanying figures. These figures are intended to be illustrative, not limiting. Although the invention is generally described in context of these embodiments, it should be understood that it is not intended to limit the scope of the invention to these particular embodiments.
Figure 1 illustrates a perspective view of a gearshift assembly for a vehicle, in accordance with an embodiment of the invention.
Figure 2 illustrates a sectional view of a gearshift assembly for a vehicle, in accordance with an embodiment of the invention.
Figure 3 illustrates another perspective view of the gearshift assembly for a vehicle, in accordance with an embodiment of the invention.
Figure 4 illustrates another perspective view of the gearshift assembly for a vehicle, in accordance with an embodiment of the invention.
Figure 5 illustrates an exploded view of the gearshift assembly for a vehicle, in accordance with an embodiment of the invention.
Figure 6A-6B illustrate perspective views of a central cam of the gearshift assembly, in accordance with an embodiment of the invention.
Figure 7A-7D illustrate different views of an upper cam of the gearshift assembly, in accordance with an embodiment of the invention.
Figure 7E-7G illustrate different views of a lower cam of the gearshift assembly, in accordance with an embodiment of the invention.
Figure 8 illustrates a perspective view of a rotary shaft of the gearshift assembly, in accordance with an embodiment of the invention.
Figure 9 illustrates a perspective view of a casing of the gearshift assembly, in accordance with and embodiment of the invention.
Figure 10A-10B illustrate perspective views of a casing upper and casing lower of the gearshift assembly, in accordance with an embodiment of the invention.
Figure 11 illustrates the method steps involved in a method for a gear change operation, in accordance with an embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION
[028] The present invention relates to a gearshift assembly. In an embodiment, the present invention relates to a gearshift assembly for a vehicle. The gearshift assembly of the present invention is typically used in a vehicle such as a two wheeled vehicle. However, it should be understood that the gearshift assembly as illustrated may find its application in a three wheeled vehicle, or a four wheeled vehicle, or other multi-wheeled vehicles, or any non-automotive application using a gearshift assembly as required.
[029] Figure 1 illustrates a perspective view of a gearshift assembly 100 for a vehicle. As illustrated, the gearshift assembly 100 comprises a lever 110 configured to be operated by a user. In an embodiment, the lever 110 is pivotally mounted on the vehicle one end and the user operated the other end of the lever in an up or down direction to perform a gearshift function. As illustrated in Figure 1 and Figure 2, the gearshift assembly 100 has a central assembly 112. The central assembly 112 is configured to be engaged with the lever 110. Further, the gearshift assembly 100 has an upper assembly 114 that is configured to alternately rotate and engage with the central assembly 112 for at least one of a gear change operation or generating a sound for notifying the rider of the gear change. Furthermore, the gearshift assembly 100 has a lower assembly 116 that is configured to alternately rotate and engage with the central assembly 112 for at least one of a gear change operation and generating a sound for notifying the rider of the gear change.
[030] As illustrated in Figure 1, and further illustrated in the embodiment depicted in Figure 2 and Figure 3, the central assembly 112 comprises a rotary shaft 120. The rotary shaft 120 is configured to rotatably provided within a casing 130, wherein the movement of the lever 110 causes the rotary shaft 120 to rotate for performing a gearshift operation. To achieve the rotation of the rotary shaft 120, the central assembly 112 has a central cam 140. The central cam 140 is rotatably provided on the rotary shaft 120. As illustrated in Figure 3, the central cam 140 has a pin 142 that protrudes radially outward. The pin 142 is configured to be engaged with the lever 110. The pin 142 being engaged with the lever 110 means that when the lever 110 is moved by the user, it causes the central cam 140 to move in the same direction.
[031] As further illustrated in Figure 4, the central cam 140 comprises a first set of helical teeth 144 (as also illustrated in Figure 6A and 6B) and a second set of helical teeth 146 (as also illustrated in Figure 6A and 6B). In an embodiment, the first set of helical teeth 144 are provided at a top end of the central cam 140 and the second set of helical teeth 146 are provided at a bottom end of the central cam 140. As further illustrated in Figure 4 and Figure 5, the upper assembly 114 has an upper cam 150. In that, the upper cam 150 is configured to be selectively engaged with the rotary shaft 120. As illustrated, the upper cam 150 has a third set of helical teeth 152 (as also illustrated in Figure 7A-7C). The third set of helical teeth 152 are configured to be alternately engaged and rotated by the first set of helical teeth 144. The alternate engagement and rotation of the third set of helical teeth 152 and the first set of helical teeth 144 is facilitated by the helical profile of the third set of helical teeth 152 and the first set of helical teeth 144. In that, as the central cam 140 moves up, the first set of helical teeth 144 push the third set of helical teeth 152 of the upper cam 150, and due to the helical profile and sloping of the helical profile of the teeth, the pushing of the third set of helical teeth 152 causes the upper cam 150 to rotate. The upper cam 150 rotates till the point when the third set of helical teeth 152 engage with the first set of helical teeth 144 of the central cam 140, which ceases the rotation of the upper cam 150.
[032] Herein, rotating of the first set of helical teeth 144 causes rotational movement of the upper cam 150 as explained above thereby rotating the rotary shaft 120 for a gear change operation. Further, the engaging of third set of helical teeth 152 with the first set of helical teeth 144 generates a sound for notifying the rider of the gear change, thereby providing the user with a feedback for a gear change operation. In an embodiment, upward movement of the central cam 140 causes rotating of the third set of helical teeth 152 and rotational movement of the upper cam 150, thereby rotating the rotary shaft 120 for an upshift gear change operation.
[033] As further illustrated in Figure 4 and 5, the lower assembly 116 has a lower cam 160. The lower cam 160 is configured to be selectively engaged with the rotary shaft 120. The lower cam 160 has a fourth set of helical teeth 162 (as also illustrated in Figure 7E and 7F). The fourth set of helical teeth 162 are configured to be alternately engaged and rotated by the second set of helical teeth 146. The alternate engagement and rotation of the fourth set of helical teeth 162 and the second set of helical teeth 146 is facilitated by the helical profile of the third set of helical teeth and the second set of helical teeth 146. In that, as the central cam 140 moves down, the second set of helical teeth 146 push the fourth set of helical teeth 162 of the lower cam 160, and due to the helical profile and sloping of the helical profile of the teeth, the pushing of the fourth set of helical teeth 162 causes the lower cam 160 to rotate. The lower cam 160 rotates till the point when the fourth set of helical teeth 162 engage with the second set of helical teeth 146 of the central cam 140, which ceases the rotation of the lower cam 160.
[034] Herein, rotating of the fourth set of helical teeth 162 causes rotational movement of the lower cam 160, thereby rotating the rotary shaft 120 for the gear change operation. Further, engaging of the fourth set of helical teeth 162 with the second set of helical teeth 146 generates a sound for notifying the rider of the gear change, thereby providing the user with a feedback for a gear change operation. In an embodiment, downward movement of the central cam 140 causes rotating of the fourth set of helical teeth 162 and rotational movement of the lower cam 160, thereby rotating the rotary shaft 120 for a downshift gear change operation. Herein, the lower cam 160 is configured to rotate in an opposite direction to a direction of rotation of the upper cam 150.
[035] Thus, when the rotary shaft 120 is rotated by engagement with the upper cam 150, the rotary shaft 120 rotates in first rotational direction, and when the rotary shaft 120 is rotated by engagement with the lower cam 160, the rotary shaft 120 rotates in second rotational direction, which is opposite to the first rotational direction.
[036] In an embodiment as illustrated in Figure 5, the gearshift assembly 100 comprises a motion sensor 180. The motion sensor 180 is configured to sense the rotation of the rotary shaft 120. The motion sensor 180 is in communication with a control unit for activating a motor for performing the gear change operation. The motion sensor 180 detects the direction of rotation of the rotary shaft 120, and communicates with the control unit for performing an upshift or a downshift gear change operation.
[037] In the embodiment as illustrated in Figure 5, the casing 130 houses the central cam 140, the upper cam 150 and the lower cam 150. Further, the gearshift assembly 100 has a first spring 170. The first spring 170 is provided between the casing 130 and the upper cam 150. The first spring 170 is configured to resist the translational movement of the upper cam 150 within the casing 130. Thus, when the user moves the lever 110 up, which in turn causes movement of the upper cam 150, the same is resisted by the first spring 170, and that resistance is felt by the user in the lever 110 providing a better feel to the user. Further, the first spring 170 also pushes the upper cam 150 back to an original position of the upper cam 150 once the first set of helical teeth 144 of the central cam 140 disengage with and move away from the third set of helical teeth 152 of the upper cam 150.
[038] In another embodiment, the gearshift assembly 100 has a second spring 172. The second spring 172 is provided between the casing 130 and the lower cam 160. The second spring 172 is configured to resist the translational movement of the lower cam 160 within the casing 130. Thus, when the user moves the lever 110 down, which in turn causes movement of the lower cam 160, the same is resisted by the second spring 172, and that resistance is felt by the user in the lever 110 providing a better feel to the user. Further, the second spring 172 also pushes the lower cam 160 back to an original position of the lower cam 160 once the second set of helical teeth 146 of the central cam 140 disengage with and move away from the fourth set of helical teeth 162 of the lower cam 160.
[039] In the embodiment depicted in Figure 7D and Figure 8, to allow for the selective engagement of the rotary shaft 120 with the upper cam 150, an upper end 120A of the rotary shaft 120 comprises an upper protrusion 122. The upper cam 150 comprises an upper recess 154. The upper protrusion 122 is configured to engage with the upper recess 154, for transmitting the rotational motion of the upper cam 150 to the rotary shaft 120. This configuration ensures that the upper cam 150 engages with the rotary shaft 120 only when the upper cam 150 is pushed up by a predetermined distance.
[040] Further, in the embodiment depicted in Figure 7G and Figure 8, to allow for the selective engagement of the rotary shaft 120 with the lower cam 160, a lower end 120B of the rotary shaft 120 comprises a lower protrusion 124 and the lower cam 160 comprises a lower recess 164. The lower protrusion 124 is configured to engage with the lower recess 164, for transmitting the rotational motion of the lower cam 160 to the rotary shaft 120. This configuration ensures that the lower cam 160 engages with the rotary shaft 120 only when the lower cam 160 is pushed down by a predetermined distance.
[041] In the embodiment depicted in Figure 9 and Figures 10A-10B, the casing 130 is configured to house the central cam 140, the upper cam 150 and the lower cam 160. For facilitation of the housing and operation of the gearshift assembly 100, in an embodiment, the casing 130 has a cylindrical profile. In an embodiment, the casing 130 comprises a casing upper 130A having a set of upper helical teeth 132, and a casing lower 130B having a set of lower helical teeth 134. Herein, the set of upper helical teeth 132 are configured to engage with the third set of helical teeth 152 of the upper cam 150 for restricting the rotational movement of the upper cam 150 and generating a sound after the upper cam 150 disengages with the central cam 140, thus providing another feedback to the user in respect of the gearshift operation.
[042] Further, the set of lower helical teeth 134 are configured to engage with the fourth set of helical teeth 162 of the lower cam 160 for restricting the rotational movement of the lower cam 160 and generating a sound after the lower cam 160 disengages with the central cam 140, thus providing another feedback to the user in respect of the gearshift operation.
[043] Thus, in an embodiment, in operation, for an upshift gear change operation, the user lifts the lever 110 up. Since the lever 110 is connected to the central cam 140 through the pin 142, the upward movement of the lever 110 causes the central cam 140 to move upwards. As the central cam 140 moves upwards, the first set of helical teeth 144 of the central cam 140 come in contact with the third set of helical teeth 152 of the upper cam 150, and the central cam 140 starts pushing the upper cam 150 against the preloaded first spring 170, which is felt by the user. As the upper cam 150 keeps moving upwards, the upper recess 154 of the upper cam 150 engages with the upper protrusion 122 on the rotary shaft 120. After the upper cam 150 moves up by a predetermined distance (for example, 10 mm), the upper cam 150 starts rotating due to helical profile of the third set of helical teeth 152 and the first set of helical teeth 144 of the central cam 140. The rotation of the upper cam 150 causes the rotary shaft 120 to rotate by a predetermined angle (for example, 120 degrees), which is detected by the motion sensor 180, which actuates the motor for the upshift gear change operation. During this rotation, the upper cam 150 moves down by a certain distance, which causes a drop in force of the first spring 170 which is felt by the user. Thereafter, the third set of helical teeth 152 engage with the first set of helical teeth 144, thereby ceasing the rotation of the upper cam 150 and generating a hitting sound, which is heard by the user. After listening to this sound, the user shall release the lever 110. In turn, the central cam 140 will move down. Once the central cam 140 moves down to disengage with the upper cam 150, the upper cam 150 further rotates till the third set of helical teeth 152 engage with the set of upper helical teeth 132 of the casing upper 130A, which generates another sound, and further downward travel of the upper cam 150 causes a further drop in force felt by the user in the lever 110. By generation of this sound, the user is notified that the upshift gear change operation is complete.
[044] In another embodiment, in operation, for a downshift gear change operation, the user presses the lever 110 down. Since the lever 110 is connected to the central cam 140 through the pin 142, the downward movement of the lever 110 causes the central cam 140 to move downwards. As the central cam 140 moves downwards, the second set of helical teeth 146 of the central cam 140 come in contact with the fourth set of helical teeth 162 of the lower cam 160, and the central cam 140 starts pushing the lower cam 160 against the preloaded second spring 172, which is felt by the user. As the lower cam 160 keeps moving downwards, the lower recess 164 of the lower cam 160 engages with the lower protrusion 124 on the rotary shaft 120. After the lower cam 150 moves down by a predetermined distance (for example, 10 mm), the lower cam 160 starts rotating due to helical profile of the fourth set of helical teeth 162 and the second set of helical teeth 146 of the central cam 140. The rotation of the lower cam 160 causes the rotary shaft 120 to rotate by a predetermined angle in an opposite direction as explained hereinbefore, which is detected by the motion sensor 180, which actuates the motor for the downshift gear change operation. During this rotation, the lower cam 160 moves up by a certain distance, which causes a drop in force of the second spring 172 which is felt by the user. Thereafter, the fourth set of helical teeth 162 engage with the second set of helical teeth 146, thereby ceasing the rotation of the lower cam 160 and generating a hitting sound, which is heard by the user. After listening to this sound, the user shall release the lever 110. In turn, the central cam 140 will move up. Once the central cam 140 moves up to disengage with the lower cam 160, the lower cam 160 further rotates till the fourth set of helical teeth 162 engage with the set of lower helical teeth 134 of the casing lower 130B, which generates another sound, and further upward travel of the lower cam 160 causes a further drop in force felt by the user in the lever 110. By generation of this sound, the user is notified that the downshift gear change operation is complete.
[045] In another aspect, the present invention relates to a method 200 for a gear change operation. The method comprises the steps of operating a lever 110 by a user. Thereafter, the method (200) has the step of moving, a central assembly 112 by operation of the lever 110 for engaging the central assembly 112 with an upper assembly 114 or a lower assembly 114. The method 200 further has the step of alternately engaging and rotating the upper assembly 114 with the central assembly 112 for at least one of a gear change operation or generating a sound for notifying the rider of the gear change. The method 200 has an alternate step and alternately engaging and rotating the lower assembly 116 with the central assembly 112 for at least one of a gear change operation or generating a sound for notifying the rider of the gear change.
[046] The method steps involved in method 200 as per an embodiment are illustrated in Figure 11. As illustrated in Figure 11, the method 200 comprises the steps of moving, a central cam 140 of the central assembly 112 by operation of the lever 110 through a pin 142 for engaging the central cam 140 with an upper cam 150 of the upper assembly 114 or a lower cam 160 of the lower assembly 116. Thereafter, the method has the step of alternately engaging and rotating a third set of helical teeth 152 of the upper cam 150 by a first set of helical teeth 144 of the central cam 140, wherein rotating of the third set of helical teeth 152 causes rotational movement of the upper cam 150, thereby rotating a rotary shaft 120 of the central assembly 112 for a gear change operation, and wherein the engaging of third set of helical teeth 152 with the first set of helical teeth 144 generates a sound for notifying the rider of the gear change. Alternatively, the method 200 has the step of alternately engaging and rotating a fourth set of helical teeth 162 of the lower cam 160 with a second set of helical teeth 146 of the central cam 140, wherein rotating of the fourth set of helical teeth 162 causes rotational movement of the lower cam 160, thereby rotating the rotary shaft 120 for the gear change operation, and wherein the engaging of the fourth set of helical teeth 162 with the second set of helical teeth 146 generates a sound for notifying the rider of the gear change.
[047] In an embodiment, the method 200 has the step of moving, the central cam 140 in an upward direction by operation of the lever 110 causing the rotation of third set of helical teeth 152; and rotating the upper cam 150, causing rotation of the rotary shaft 120 for an upshift gear change operation. In another embodiment, the method 200 has the step of moving, the central cam 140 in a downward direction by operation of the lever 110 causing the rotation of fourth set of helical teeth 162; and rotating the lower cam 160, causing rotation of the rotary shaft 120 for a downshift gear change operation.
[048] In a further embodiment, the method 200 has the steps of engaging a set of upper helical teeth 132 on a casing upper 130A with the third set of helical teeth 152 for restricting the rotational movement of the upper cam 150 and generating a sound; and engaging a set of lower helical teeth 134 on a casing lower 130B with the fourth set of helical teeth 162 for restricting the rotational movement of the lower cam 160 for restricting the movement of the lower cam 160 and generating a sound. The method 200 further has the step of sensing, by a motion sensor 180, rotation of the rotary shaft 120; and activating, by a control unit in communication with the motion sensor 180, a motor for performing a gearshift operation.
[049] Thus, in operation, as illustrated in the embodiment depicted in Figure 11, at step 202 the user moves the lever 110. If the user moves the lever 110 up, the method 200 moves to step 204, and if the user moves the lever 110 down, the method 200 moves to step 220. At step 204, the central cam 140 moves in the upward direction and at step 206, the upper cam 150 is rotated by the central cam 140 as explained hereinbefore. Thereafter, at step 208, the upper cam 150 rotates the rotary shaft 120 for an upshift gear change operation, and at step 210, the third set of helical teeth 152 of the upper cam 150 engage with the first set of helical teeth 144 on the central cam 140 thereby generating a sound as explained hereinbefore. Thereafter at step 212, the lever 110 is released by the user, post which at step 214, the third set of helical teeth 152 engage with the set of upper helical teeth 132 on the casing upper 130A for generating a sound.
[050] Alternatively, at step 220, the central cam 140 moves in the downward direction and at step 222, the lower cam 160 is rotated by the central cam 140 as explained hereinbefore. Thereafter, at step 224, the lower cam 160 rotates the rotary shaft 120 for a downshift gear change operation, and at step 226, the fourth set of helical teeth 162 of the lower cam 160 engage with the second set of helical teeth 146 on the central cam 140 thereby generating a sound as explained hereinbefore. Thereafter at step 228, the lever 110 is released by the user, post which at step 230, the fourth set of helical teeth 162 engage with the set of lower helical teeth 134 on the casing lower 130B for generating a sound.
[051] Advantageously, the present invention provides a gearshift assembly for a vehicle that allows elimination of a conventional four bar linkage mechanism to link the lever to the transmission. Elimination of the conventional four bar linkage mechanism allows for both a footrest/peg of the vehicle as well as the lever to be adjustable in accordance with the ergonomic requirements of the user.
[052] Further, the gearshift assembly provides for the user to receive feedback for the gear change operation, in the form of sounds generated during upshift as well as the downshift operation. This allows for the user to know that the gear change operation has been completed on moving the lever, post which the user can release the lever. Conversely, till the user hears the sound, the user can keep operating/pushing the lever to perform the gear change operation, which results in better predictability and better riding characteristics in relation to the gearshift operation.
[053] Further, the change in force felt by the user in the lever at various stages of the gear change operation also allows for better transmission feel and predictability for the user.
[054] While the present invention has been described with respect to certain embodiments, it will be apparent to those skilled in the art that various changes and modification may be made without departing from the scope of the invention as defined in the following claims.

List of Reference Numerals
100: Gearshift Assembly
110: Lever
112: Central Assembly
114: Upper Assembly
116: Lower Assembly
120: Rotary Shaft
120A: Upper end of the Rotary Shaft
120B: Lower end of the Rotary Shaft
122: Upper Protrusion
124: Lower Protrusion
130: Casing
130A: Casing Upper
130B: Casing Lower
132: Set of Upper Helical teeth
134: Set of Lower Helical teeth
140: Central Cam
142: Pin
144: First Set of Helical teeth
146: Second Set of Helical teeth
150: Upper Cam
152: Third Set of Helical teeth
154: Upper Recess
160: Lower Cam
162: Fourth Set of Helical teeth
164: Lower Recess
170: First Spring
172: Second Spring
180: Motion Sensor
200: Method for a gear change operation , Claims:WE CLAIM:
1. A gearshift assembly (100) for a vehicle, the gearshift assembly (100) comprising:
a lever (110), the lever (110) configured to be operated by a user;
a central assembly (112), the central assembly (112) configured to be engaged with the lever (110);
an upper assembly (114), the upper assembly (114) configured to alternately rotate and engage with the central assembly (112) for at least one of a gear change operation or generating a sound for notifying the rider of the gear change; and
a lower assembly (116), the lower assembly (116) configured to alternately rotate and engage with the central assembly (112) for at least one of a gear change operation or generating a sound for notifying the rider of the gear change.

2. The gearshift assembly (100) as claimed in claim 1, wherein the central assembly (112) comprises a rotary shaft (120), the rotary shaft (120) configured to rotatably provided within a casing (130); and
a central cam (140), the central cam (140) rotatably provided on the rotary shaft (120), the central cam (140) having a pin (142) protruding radially outward, the pin (142) being configured to be engaged with the lever (110), the central cam (140) comprising a first set of helical teeth (144), and a second set of helical teeth (146).

3. The gearshift assembly (100) as claimed in claim 2, wherein the upper assembly (114) comprises an upper cam (150), the upper cam (150) being configured to be selectively engaged with the rotary shaft (120), the upper cam (150) having a third set of helical teeth (152) configured to be alternately engaged and rotated by the first set of helical teeth (144), wherein rotating of the third set of helical teeth (152) causes rotational movement of the upper cam (150), thereby rotating the rotary shaft (120) for a gear change operation, and wherein the engaging of third set of helical teeth (152) with the first set of helical teeth (144) generates a sound for notifying the rider of the gear change;

4. The gearshift assembly (100) as claimed in claim 2, wherein the lower assembly (116) comprises a lower cam (160), the lower cam (160) being configured to be selectively engaged with the rotary shaft (120), the lower cam (160) having a fourth set of helical teeth (162) configured to be alternately engaged and rotated by the second set of helical teeth (146), wherein rotating of the fourth set of helical teeth (162) causes rotational movement of the lower cam (160), thereby rotating the rotary shaft (120) for the gear change operation, and wherein the engaging of the fourth set of helical teeth (162) with the second set of helical teeth (146) generates a sound for notifying the rider of the gear change.

5. The gearshift assembly (100) as claimed in claim 3, wherein upward movement of the central cam (140) causes rotating of the third set of helical teeth (152) and rotational movement of the upper cam (150), thereby rotating the rotary shaft (120) for an upshift gear change operation.

6. The gearshift assembly (100) as claimed in claim 4, wherein downward movement of the central cam (140) causes rotating of the fourth set of helical teeth (162) and rotational movement of the lower cam (160), thereby rotating the rotary shaft (120) for a downshift gear change operation, wherein the lower cam (160) is configured to rotate in an opposite direction to a direction of rotation of the upper cam (150).

7. The gearshift assembly (100) as claimed in claim 3 or 4, wherein the casing (130) is configured to house the central cam (140), the upper cam (150) and the lower cam (160), the casing (130) having a cylindrical profile.

8. The gearshift assembly (100) as claimed in claim 7, wherein the casing (130) comprises a casing upper (130A) having a set of upper helical teeth (132), and a casing lower (130B) having a set of lower helical teeth (134), wherein the set of upper helical teeth (132) configured to engage with the third set of helical teeth (152) of the upper cam (150) for restricting the rotational movement of the upper cam (150) and generating a sound, and the set of lower helical teeth (134) being configured to engage with the fourth set of helical teeth (162) of the lower cam (160) for restricting the rotational movement of the lower cam (160) and generating a sound.

9. The gearshift assembly (100) as claimed in claim 7, comprising a first spring (170), the first spring (170) provided between the casing (130) and the upper cam (150), the first spring (170) being configured to resist the translational movement of the upper cam (150) within the casing (130).

10. The gearshift assembly (100) as claimed in claim 7, comprising a second spring (172), the second spring (172) provided between the casing (130) and the lower cam (160), the second spring (172) being configured to resist the translational movement of the lower cam (160) within the casing (130).

11. The gearshift assembly (100) as claimed in claim 2, comprising a motion sensor (180), the motion sensor (180) being configured to sense the rotation of the rotary shaft (120), the motion sensor (180) being in communication with a control unit for activating a motor for performing the gear change operation.

12. The gearshift assembly (100) as claimed in claim 3, wherein an upper end (120A) of the rotary shaft (120) comprises an upper protrusion (122), and the upper cam (150) comprises an upper recess (154), the upper protrusion (122) being configured to engage with the upper recess (154), for transmitting the rotational motion of the upper cam (150) to the rotary shaft (120).

13. The gearshift assembly (100) as claimed in claim 4, wherein a lower end (120B) of the rotary shaft (120) comprises a lower protrusion (124), and the lower cam (160) comprises a lower recess (164), the lower protrusion (124) being configured to engage with the lower recess (164), for transmitting the rotational motion of the lower cam (160) to the rotary shaft (120).

14. A method (200) for a gear change operation, comprising a steps of:
operating a lever (110) by a user;
moving, a central assembly (112) by operation of the lever (110) for engaging the central assembly (112) with an upper assembly (114) or a lower assembly (114);
alternately engaging and rotating the upper assembly (114) with the central assembly (112) for at least one of a gear change operation or generating a sound for notifying the rider of the gear change; or
alternately engaging and rotating the lower assembly (116) with the central assembly (112) for at least one of a gear change operation or generating a sound for notifying the rider of the gear change.

15. The method (200) as claimed in claim 14, comprising the steps of:
moving, a central cam (140) of the central assembly (112), by operation of the lever (110) through a pin (142) for engaging the central cam (140) with an upper cam (150) of the upper assembly (114) or a lower cam (160) of the lower assembly (116).

16. The method (200) as claimed in claim 15, comprising the steps of:
alternately engaging and rotating a third set of helical teeth (152) of the upper cam (150) by a first set of helical teeth (144) of the central cam (140), wherein rotating of the third set of helical teeth (152) causes rotational movement of the upper cam (150), thereby rotating a rotary shaft (120) for a gear change operation, and wherein the engaging of third set of helical teeth (152) with the first set of helical teeth (144) generates a sound for notifying the rider of the gear change.

17. The method (200) as claimed in claim 15, comprising the steps of:
alternately engaging and rotating a fourth set of helical teeth (162) of the lower cam (160) by a second set of helical teeth (146) of the central cam (140), wherein rotating of the fourth set of helical teeth (162) causes rotational movement of the lower cam (160), thereby rotating the rotary shaft (120) for the gear change operation, and wherein the engaging of the fourth set of helical teeth (162) with the second set of helical teeth (146) generates a sound for notifying the rider of the gear change.

18. The method (200) as claimed in claim 16, comprising the steps of:
moving, the central cam (140) in an upward direction by operation of the lever (110) causing the rotation of third set of helical teeth (152); and
rotating the upper cam (150), causing rotation of the rotary shaft (120) for an upshift gear change operation.

19. The method (200) as claimed in claim 17, comprising the steps of:
moving, the central cam (140) in a downward direction by operation of the lever (110) causing the rotation of fourth set of helical teeth (162); and
rotating the lower cam (160), causing rotation of the rotary shaft (120) for a downshift gear change operation.

20. The method (200) as claimed in claim 16 or 17, comprising the steps of:
engaging a set of upper helical teeth (132) on a casing upper (130A) with the third set of helical teeth (152) for restricting the rotational movement of the upper cam (150) and generating a sound: and
engaging a set of lower helical teeth (134) on a casing lower (130B) with the fourth set of helical teeth (162) for restricting the rotational movement of the lower cam (160) for restricting the movement of the lower cam (160) and generating a sound.

21. The method as claimed in claim 16 or 17, comprising the steps of:
sensing, by a motion sensor (180), rotation of the rotary shaft (120); and
activating, by a control unit in communication with the motion sensor (180), a motor for performing a gearshift operation.

Dated this 20th day of March 2024
TVS MOTOR COMPANY LIMITED
By their Agent & Attorney

(Nikhil Ranjan)
of Khaitan & Co
Reg No IN/PA-1471