TECHNICAL FIELD
Embodiments of the present invention relate generally to automatic transmissions and more specifically to a gear shifter assembly for an automatic transmission of a vehicle.
BACKGROUND ART 5
An automatic transmission usually includes a gear shift lever for shifting between a park, a reverse, a neutral and a drive positions. Another, variation of the automatic transmissions, known as an automatic manual transmission (AMT) also requires the gear shift lever to be shifted to a manual mode, where shifting of gears is as per manual inputs. Various 10 security requirements demand that the gear shift lever of the automatic transmission (or the automatic manual transmission) not be shifted from a park position or a neutral position or a reverse position, without taking prescribed security precautions.
Conventional methods of achieving the same involves use of shift 15 lock buttons and solenoids. While shift lock buttons are adapted to be manually pressed, the solenoids are actuated in response to one or more inputs. Some examples of the one or more input include pressing of a brake pedal or a vehicular speed value or a direction of motion of the vehicle etc. However, in most of the solutions in the art, at least two solenoids are 20 required, one for locking the gear shift lever in the park position and the other solenoid for locking the gear shift lever in the neutral position. Use of two or more solenoids can be a costly proposition, also it leads to added complexity and packaging issues. There have been a number of solutions suggested in the art employing only a single solenoid. Some of these 25 solutions include DE4217773A1, US7530286B2, WO02/08008A1, US6009769A and EP1271009B1. However, each of these solutions include a large number of components and added complexity and costs.
Therefore, in light of the discussion above, there is a need in the art
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for a gear shifter assembly for an automatic transmission of a vehicle, which does not suffer from above mentioned deficiencies.
SUMMARY OF THE INVENTION
Embodiments of the present invention aim to provide a gear shifter assembly for an automatic transmission of a vehicle. The gear shifter 5 assembly employs a single solenoid to lock a gear shift lever in a park and a neutral position. Further, the gear shifter assembly is simple and cost effective to manufacture.
In accordance with an embodiment of the present invention, a gear shifter assembly for an automatic transmission of a vehicle, comprises a 10 gear shift lever having a knob assembly at a first end and a shift cable connected at a second end, a first link having a first top end and adapted to pivot about a first pivot point, between a first lock position and a first release position, a second link having a second top end and adapted to pivot about a second pivot point, between a second lock position and a second release 15 position, a solenoid having a plunger and placed in a substantially transverse direction with respect to the first link and the second link, the plunger being adapted to move from a plunger released position to a plunger retracted position, when the solenoid is actuated, a transverse link mechanism connected with the first link, the second link and the plunger. 20 Further, the gear shift lever is adapted to shift between at least a park, a reverse, a neutral and a drive positions. Further, when in the first lock position, the first link is adapted to arrest the shifting of the gear shift lever from the neutral to the reverse positions. Further, when in the second lock position, the second link is adapted to arrest the shifting of the gear shift 25 lever from the park to the reverse positions. Further, the transverse link mechanism is adapted to maintain the first link and the second link in the first lock position and the second lock position, respectively, when the plunger is in the plunger released position. Also, the transverse link mechanism is adapted to maintain the first link and the second link in the 30
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first release position and the second release position, respectively, when the plunger is in the plunger retracted position.
In accordance with an embodiment of the present invention, the transverse link mechanism is connected with the first link at a first connection point, such that, the first pivot point lies between the first top end 5 and the first connection point.
In accordance with an embodiment of the present invention, the transverse link mechanism is connected with the second link at a second connection point, such that, the second connection point lies between the second top end and the second pivot point. 10
In accordance with an embodiment of the present invention, the solenoid is adapted to actuate on pressing of a brake pedal of the vehicle.
In accordance with an embodiment of the present invention, the knob assembly further comprises a shift lock button adapted to shift between a button pressed position and a button released position. 15
In accordance with an embodiment of the present invention, the gear shifter assembly further comprises a locking link mechanism connected with the shift lock button, wherein, when the shift lock button is in the button released position, the locking link mechanism is adapted to arrest the shifting of the gear shift lever from, the park positon to the reverse position, 20 the reverse position to the park position and the neutral position to the reverse position.
In accordance with an embodiment of the present invention, the locking link mechanism further comprises a locking pin, the locking pin being perpendicular to a plane of the gear shift lever. Further, when the gear shift 25 lever is in the neutral position, the locking pin is adapted to slide downwards and upwards in a first groove, on pressing and release of the shift lock
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button, respectively. Further, on pressing of the shift lock button, the locking pin is adapted to slide downwards and out of the first groove and allow a shifting of the gear shift lever from the neutral position to the reverse position. Further, on release of the shift lock button, the locking pin is adapted to slide upwards in the first groove and arrest the shifting of the gear shift lever from 5 the neutral position to the reverse position.
In accordance with an embodiment of the present invention, in the first lock position, the first top end of the first link is adapted to arrest the downward sliding of the locking pin, in the first groove, thereby arresting the shifting of the gear shift lever from the neutral position to the reverse position. 10
In accordance with an embodiment of the present invention, when the gear shift lever is in the park position, the locking pin is adapted to slide downwards and upwards in a second groove, on pressing and release of the shift lock button, respectively. Further, on pressing of the shift lock button, the locking pin is adapted to slide downwards and out of the second groove 15 and allow a shifting of the gear shift lever from the park position to the reverse position. Further, on release of the shift lock button, the locking pin is adapted to slide upwards in the second groove and arrest the shifting of the gear shift lever from the park position to the reverse position.
In accordance with an embodiment of the present invention, in the 20 second lock position, the second top end of the second link is adapted to arrest the downward sliding of the locking pin, in the second groove, thereby arresting the shifting of the gear shift lever from the park position to the reverse position.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS 25
So that the manner in which the above recited features of the present invention can be understood in detail, a more particular description of the invention, briefly summarized above, may have been referred by embodiments, some of which are illustrated in the appended drawings. It is
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to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.
These and other features, benefits, and advantages of the present 5 invention will become apparent by reference to the following text figure, with like reference numbers referring to like structures across the views, wherein:
Fig. 1 illustrates a gear shifter assembly for an automatic transmission of a vehicle, in accordance with an embodiment of the present invention; 10
Fig. 2 illustrates a housing for the gear shifter assembly, in accordance with an embodiment of the present invention;
Fig. 3 illustrates a cross sectional view of the gear shifter assembly, in accordance with an embodiment of the present invention; and
Fig. 4 illustrates a cross sectional view of the gear shifter assembly, 15 in accordance with another embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
While the present invention is described herein by way of example using embodiments and illustrative drawings, those skilled in the art will recognize that the invention is not limited to the embodiments of drawing or 20 drawings described, and are not intended to represent the scale of the various components. Further, some components that may form a part of the invention may not be illustrated in certain figures, for ease of illustration, and such omissions do not limit the embodiments outlined in any way. It should be understood that the drawings and detailed description thereto are not 25 intended to limit the invention to the particular form disclosed, but on the contrary, the invention is to cover all modifications, equivalents, and
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alternatives falling within the scope of the present invention as defined by the appended claim. As used throughout this description, the word "may" is used in a permissive sense (i.e. meaning having the potential to), rather than the mandatory sense, (i.e. meaning must). Further, the words "a" or "an" mean "at least one” and the word “plurality” means “one or more” unless 5 otherwise mentioned. Furthermore, the terminology and phraseology used herein is solely used for descriptive purposes and should not be construed as limiting in scope. Language such as "including," "comprising," "having," "containing," or "involving," and variations thereof, is intended to be broad and encompass the subject matter listed thereafter, equivalents, and 10 additional subject matter not recited, and is not intended to exclude other additives, components, integers or steps. Likewise, the term "comprising" is considered synonymous with the terms "including" or "containing" for applicable legal purposes. Any discussion of documents, acts, materials, devices, articles and the like is included in the specification solely for the 15 purpose of providing a context for the present invention. It is not suggested or represented that any or all of these matters form part of the prior art base or were common general knowledge in the field relevant to the present invention.
In this disclosure, whenever a composition or an element or a group 20 of elements is preceded with the transitional phrase “comprising”, it is understood that we also contemplate the same composition, element or group of elements with transitional phrases “consisting of”, “consisting”, “selected from the group of consisting of, “including”, or “is” preceding the recitation of the composition, element or group of elements and vice versa. 25
The present invention is described hereinafter by various embodiments with reference to the accompanying drawing, wherein reference numerals used in the accompanying drawing correspond to the like elements throughout the description. This invention may, however, be embodied in many different forms and should not be construed as limited to 30
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the embodiment set forth herein. Rather, the embodiment is provided so that this disclosure will be thorough and complete and will fully convey the scope of the invention to those skilled in the art. In the following detailed description, numeric values and ranges are provided for various aspects of the implementations described. These values and ranges are to be treated as 5 examples only, and are not intended to limit the scope of the claims. In addition, a number of materials are identified as suitable for various facets of the implementations. These materials are to be treated as exemplary, and are not intended to limit the scope of the invention.
Referring to the drawings, the invention will now be described in 10 more detail. Figure 1 illustrates a gear shifter assembly 100 for an automatic transmission of a vehicle, in accordance with an embodiment of the present invention. It is to be noted here that the automatic transmission here also includes automatic manual transmission (AMT) as a subset. As shown in figure 1, the gear shifter assembly 100 includes a gear shift lever 110 15 having a knob assembly 120 at a first end 112 and a shift cable connected at a second end 114. The knob assembly 120 further comprises a shift lock button 122 adapted to shift between a button pressed position and a button released position. The shift lock button 122 is adapted to be shifted between the button pressed position and the button released position by a driver of 20 the vehicle.
Figure 2 illustrates a housing 210 for the gear shifter assembly 100, in accordance with an embodiment 200 of the present invention. As can be seen from the figure 2, the gear shift lever 110 is adapted to shift between at least a park (P), a reverse (R), a neutral (N) and a drive (D) positions. In 25 accordance with an embodiment, the gear shift lever 110 is further configured to shift into a manual (M) mode, where, in use, the automatic transmission is shifted as per a manual input of the driver. In that manner, it will be appreciated by a person skilled in the art, that a sensor may be connected to read the shifting of the gear shift lever 110 in the manual mode. 30
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The sensor may then communicate a position of the gear shift lever 110 to a microprocessor. The microprocessor may then shift the automatic transmission based on the position of the gear shift lever 110 in the manual mode.
Figure 3 illustrates a cross sectional view of the gear shifter 5 assembly 100, in accordance with an embodiment 300 of the present invention. As can be seen in figure 3, the gear shifter assembly 100 further comprises a first link 310 having a first top end 312 and adapted to pivot about a first pivot point 314. Further, the first link 310 is adapted to pivot between a first lock position and a first release position. Further, when in the 10 first lock position, the first link 310 is adapted to arrest the shifting of the gear shift lever 110 from the neutral to the reverse positions. The gear shifter assembly 100 further comprises a second link 320 having a second top end 322 and adapted to pivot about a second pivot point 324, between a second lock position and a second release position. Further, when in the second 15 lock position, the second link 320 is adapted to arrest the shifting of the gear shift lever 110 from the park to the reverse positions.
Further, the gear shifter assembly 100 comprises a solenoid 330 having a plunger 332. The solenoid 330 is placed in a substantially transverse direction with respect to the first link 310 and the second link 320. 20 Further, the plunger 332 is adapted to move from a plunger released position to a plunger retracted position, when the solenoid 330 is actuated. When the actuation is removed, a spring brings the plunger 332 from the plunger retracted position to the plunger released position. In accordance with an embodiment, the solenoid 330 is adapted to actuate on pressing of 25 a brake pedal of the vehicle.
In that manner, it is envisaged, that the brake pedal is connected with a motion sensor. The motion sensor is adapted to read a position of the brake pedal. When the brake pedal is pressed the motion sensor sends a
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first signal, indicative of the pressing of the brake pedal to the microprocessor. The microprocessor then closes a circuit supplying current to the solenoid 330 and the solenoid 330 is actuated. In accordance with an another embodiment, the solenoid 330 is actuated by the microprocessor based on one or more additional inputs. In accordance with an embodiment, 5 the one or more additional inputs include, but are not limited to, a speed of a vehicle, a direction of motion of the vehicle and proximity of other entities, such as humans and other vehicles, at a rear or a front sides of the vehicle.
Further, the gear shifter assembly 100 comprises a transverse link mechanism 340 connected with the first link 310, the second link 320 and 10 the plunger 332. In accordance with an embodiment, the transverse link mechanism 340 comprises a plurality of links in series. In accordance with an embodiment, each one of the plurality of links is pivotable with respect to an adjoining link. The transverse link mechanism 340 is adapted to maintain the first link 310 and the second link 320 in the first lock position and the 15 second lock position, respectively, when the plunger 332 is in the plunger released position. In accordance with an embodiment, the transverse link mechanism 340 is connected with the first link 310 at a first connection point 316, such that, the first pivot point 314 lies between the first top end 312 and the first connection point 316. 20
Further, in accordance with an embodiment, the transverse link mechanism 340 is connected with the second link 320 at a second connection point 326, such that, the second connection point 326 lies between the second top end 322 and the second pivot point 324. In that manner, when the plunger 332 moves from the plunger released position to 25 the plunger retracted position, the first link 310 pivots in a first angular direction and the second link 320 pivots in a direction opposite to the first angular direction. In this manner, the gear shift lever 110 cannot transition from the neutral to the reverse position or from the park to reverse position until the solenoid 330 is actuated and the plunger 332 is moved to the 30
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plunger retracted position.
In accordance with an embodiment, the gear shifter assembly further comprises a locking link mechanism 350 (not shown in figure 3) connected with the shift lock button 122. Further, when the shift lock button 122 is in the button released position, the locking link mechanism 350 is 5 adapted to arrest the shifting of the gear shift lever 110 from the park positon to the reverse position, the reverse position to the park position and the neutral position to the reverse position. This way an additional layer of security is added and the automatic transmission cannot be shifted from the park positon to the reverse position, the reverse position to the park position 10 and the neutral position to the reverse position, until the shift lock button 122 is pressed to the button pressed position.
In accordance with an embodiment of the present invention, the locking link mechanism 350 further comprises a locking pin 352, the locking pin 352 being perpendicular to a plane of the gear shift lever 110. When the 15 gear shift lever 110 is in the neutral position, the locking pin 352 is adapted to slide downwards and upwards in a first groove 360, on pressing and release of the shift lock button 122, respectively. On pressing of the shift lock button 122, the locking pin 352 is adapted to slide downwards and out of the first groove 360 and allow a shifting of the gear shift lever 110 from 20 the neutral position to the reverse position. On release of the shift lock button 122, the locking pin 352 is adapted to slide upwards in the first groove 360 and arrest the shifting of the gear shift lever 110 from the neutral position to the reverse position. However, in the first lock position, the first top end 312 of the first link 310 is adapted to arrest the downward sliding of 25 the locking pin 352, in the first groove 360, thereby arresting the shifting of the gear shift lever 110 from the neutral position to the reverse position.
Further, when the gear shift lever 110 is in the park position, the locking pin 352 is adapted to slide downwards and upwards in a second
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groove 370, on pressing and release of the shift lock button 122, respectively. On pressing of the shift lock button 122, the locking pin 352 is adapted to slide downwards and out of the second groove 370 and allow a shifting of the gear shift lever 110 from the park position to the reverse position. On release of the shift lock button 122, the locking pin 352 is 5 adapted to slide upwards in the second groove 370 and arrest the shifting of the gear shift lever 110 from the park position to the reverse position. However, in the second lock position, the second top end 322 of the second link 320 is adapted to arrest the downward sliding of the locking pin 352, in the second groove 370, thereby arresting the shifting of the gear shift lever 10 110 from the park position to the reverse position.
Figure 4 illustrates a cross sectional view of the gear shifter assembly 100, in accordance with another embodiment 400 of the present invention. Here the shift lock button 122 is in the button pressed position and the plunger 322 is in the plunger retracted position. Further, the 15 transverse link mechanism 340 is adapted to maintain the first link 310 and the second link 320 in the first release position and the second release position, respectively, when the plunger 322 is in the plunger retracted position. As can be further seen from the figure 4, the locking pin 352 is in the first groove 360 and the first link 310 is in the first release position. 20 Therefore, on pressing of the shift lock button 122, the locking pin 352 is free to slide downwards and out of the first groove 360, thereby allowing the gear shift lever 110 to shift from the park position to the reverse position.
In use, when in the first lock position, the first link 310 arrests the shifting of the gear shift lever 110 from the neutral to the reverse positions. 25 Further, when in the second lock position, the second link 320 arrests the shifting of the gear shift lever 110 from the park to the reverse positions. Further, the transverse link mechanism 340 is maintains the first link 310 and the second link 320 in the first lock position and the second lock position, respectively, when the plunger 332 is in the plunger released position. Also, 30
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the transverse link mechanism 340 maintains the first link 310 and the second link 320 in the first release position and the second release position, respectively, when the plunger 332 is in the plunger retracted position.
In accordance with an embodiment, the solenoid 330 is to actuated on pressing of the brake pedal of the vehicle. Further, in accordance with 5 an embodiment, when the shift lock button 122 is in the button released position, the locking link mechanism 350 arrests the shifting of the gear shift lever 110 from the park positon to the reverse position, the reverse position to the park position and the neutral position to the reverse position.
In accordance with an embodiment, when said gear shift lever 110 10 is in the neutral position, the locking pin 352 slides downwards and upwards in the first groove 360, on pressing and release of the shift lock button 122, respectively. Further, on pressing of the shift lock button 122, the locking pin 352 slides downwards and out of the first groove 360 and allows the shifting of the gear shift lever 110 from the neutral position to the reverse position. 15 Further, on release of the shift lock button 122, the locking pin 352 slides upwards in the first groove 360 and arrests the shifting of the gear shift lever 110 from the neutral position to the reverse position. In accordance with an embodiment, in the first lock position, the first top end 312 of the first link 310 arrests the downward sliding of the locking pin 352, in the first groove 20 360, thereby arresting the shifting of the gear shift lever 110 from the neutral position to the reverse position.
In accordance with an embodiment, when the gear shift lever 110 is in the park position, the locking pin 352 slides downwards and upwards in the second groove 370, on pressing and release of the shift lock button 122, 25 respectively. Further, on pressing of the shift lock button 122, the locking pin 352 slides downwards and out of the second groove 370 and allows a shifting of said gear shift lever 110 from the park position to the reverse position. Further, on release of the shift lock button 122, the locking pin 352
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slides upwards in the second groove 370 and arrests the shifting of the gear shift lever 110 from the park position to the reverse position. In accordance with an embodiment, in the second lock position, the second top end 322 of the second link 320 arrests the downward sliding of the locking pin 352, in the second groove 370, thereby arresting the shifting of the gear shift lever 5 110 from the park position to the reverse position.
Hence, the gear shifter assembly 100 employs a single solenoid 330 to lock a gear shift lever 110 in a park and a neutral position. Further, the gear shifter assembly 100 is simple and cost effective to manufacture.
Various modifications to these embodiments are apparent to those 10 skilled in the art from the description and the accompanying drawings. The principles associated with the various embodiments described herein may be applied to other embodiments. Therefore, the description is not intended to be limited to the embodiments shown along with the accompanying drawings but is to be providing broadest scope of consistent with the 15 principles and the novel and inventive features disclosed or suggested herein. Accordingly, the invention is anticipated to hold on to all other such alternatives, modifications, and variations that fall within the scope of the present invention and appended claims.

We Claim:
1. A gear shifter assembly (100) for an automatic transmission of a vehicle, the gear shifter assembly (100) comprising:
a gear shift lever (110) having a knob assembly (120) at a first 5 end (112) and a shift cable connected at a second end (114);
a first link (310) having a first top end (312) and adapted to pivot about a first pivot point (314), between a first lock position and a first release position;
a second link (320) having a second top end (322) and 10 adapted to pivot about a second pivot point (324), between a second lock position and a second release position;
a solenoid (330) having a plunger (332) and placed in a substantially transverse direction with respect to said first link (310) and said second link (320), said plunger (332) being adapted to move 15 from a plunger released position to a plunger retracted position, when said solenoid (330) is actuated; and
a transverse link mechanism (340) connected with said first link (310), said second link (320) and said plunger (332);
wherein said gear shift lever (110) is adapted to shift between 20 at least a park, a reverse, a neutral and a drive positions;
wherein, when in said first lock position, said first link (310) is adapted to arrest said shifting of said gear shift lever (110) from said neutral to said reverse positions;
wherein, when in said second lock position, said second link 25 (320) is adapted to arrest said shifting of said gear shift lever (110) from said park to said reverse positions;
wherein said transverse link mechanism (340) is adapted to maintain said first link (310) and said second link (320) in said first lock position and said second lock position, respectively, when said 30 plunger (332) is in said plunger released position; and
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wherein said transverse link mechanism (340) is adapted to maintain said first link (310) and said second link (320) in said first release position and said second release position, respectively, when said plunger (332) is in said plunger retracted position.
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2. The gear shifter assembly (100) as claimed in claim 1, wherein said transverse link mechanism (340) is connected with said first link (310) at a first connection point (316), such that, said first pivot point (314) lies between said first top end (312) and said first connection point (316). 10
3. The gear shifter assembly (100) as claimed in claim 1, wherein said transverse link mechanism (340) is connected with said second link (320) at a second connection point (326), such that, said second connection point (326) lies between said second top end (322) and 15 said second pivot point (324).
4. The gear shifter assembly (100) as claimed in claim 1, wherein said solenoid (330) is adapted to actuate on pressing of a brake pedal of said vehicle. 20
5. The gear shifter assembly (100) as claimed in claim 1, wherein said knob assembly (120) further comprises a shift lock button (122) adapted to shift between a button pressed position and a button released position. 25
6. The gear shifter assembly (100) as claimed in claim 5, further comprising a locking link mechanism (350) connected with said shift lock button (122), wherein, when said shift lock button (122) is in said button released position, said locking link mechanism (350) is 30 adapted to arrest said shifting of said gear shift lever (110) from:
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said park positon to said reverse position;
said reverse position to said park position; and
said neutral position to said reverse position.
7. The gear shifter assembly (100) as claimed in claim 6, wherein said 5 locking link mechanism (350) further comprises a locking pin (352), said locking pin (352) being perpendicular to a plane of said gear shift lever (110);
wherein, when said gear shift lever (110) is in said neutral position, said locking pin (352) is adapted to slide downwards and 10 upwards in a first groove (360), on pressing and release of said shift lock button (122), respectively;
wherein, on pressing of said shift lock button (122), said locking pin (352) is adapted to slide downwards and out of said first groove (360) and allow a shifting of said gear shift lever (110) from 15 said neutral position to said reverse position;
wherein, on release of said shift lock button (122), said locking pin (352) is adapted to slide upwards in said first groove (360) and arrest said shifting of said gear shift lever (110) from said neutral position to said reverse position. 20
8. The gear shifter assembly (100) as claimed in claim 7, wherein, in said first lock position, said first top end (312) of said first link (310) is adapted to arrest said downward sliding of said locking pin (352), in said first groove (360), thereby arresting said shifting of said gear 25 shift lever (110) from said neutral position to said reverse position.
9. The gear shifter assembly (100) as claimed in claim 7, wherein, when said gear shift lever (110) is in said park position, said locking pin (352) is adapted to slide downwards and upwards in a second groove 30 (370), on pressing and release of said shift lock button (122),
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respectively;
wherein, on pressing of said shift lock button (122), said locking pin (352) is adapted to slide downwards and out of said second groove (370) and allow a shifting of said gear shift lever (110) from said park position to said reverse position; 5
wherein, on release of said shift lock button (122), said locking pin (352) is adapted to slide upwards in said second groove (370) and arrest said shifting of said gear shift lever (110) from said park position to said reverse position
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10. The gear shifter assembly (100) as claimed in claim 9, wherein, in said second lock position, said second top end (322) of said second link (320) is adapted to arrest said downward sliding of said locking pin (352), in said second groove (370), thereby arresting said shifting of said gear shift lever (110) from said park position to said reverse 15 position.