FIELD OF INVENTION
This invention is directed to gear shifter assembly with variable lever ratio for
vehicle.
BACKGROUND1 PRIOR ART
Gear shift lever is an integral part of gear shift system which is attached tn gear
shift lever assembly (GSLA). The purpose of said lever is to act as interface
between driver and gear box which enables driver to shift the gears. It also
contributes towards the overall shift efforts requirements. As it is known lever
ratio is inversely proportional to gear shifting efforts; which is defined as
follows:
Lever Ratio =
L2
LI: Distance between centre of pivot ball to tip of lever rod (knob center).
L2: Centre to centre distance between pivot ball and shift pin of lever
assembly. . .
Currently existing gear shift lever assembly is illustrated in fig. 1
indicating the following: -
Socket Liner- 1 .
Noise Damper-5
Shift Pin-7
Spring (Anti Noise)-9
f Fixation Shaft- 1 1
I BII.& (4 places)- 13
Lugs on socket-L
Lever Rod-2.
Axle Lever Selection-4
Pivot . Ba. ll-6
Aronlock Washer-8
Shifter Box- 10
Bell Crank- 12
Silent Block (4 places)- 14
In the current system the gear lever constitutes a single body with pivot ball
over molded to it which in turn is assembled to the GSLA housing. There is a
socket liner between the pivot ball and housing. Thus, in the existing system
the lever rod is'assembled to the GSLA with pivot ball as the pivot point on the
housing & lever interface about which the lever moves. as per the desired gear
position.
Further 'in the current lever assembly the gear lever (1) constitutes a single
piece with .pivot ball (2) over molded thereto as shown in fig. 2 which in turn is
assembled to the lever assembly housing.
The lever, one end of which is connected to shift pin (3) for connection with the . . .
cable and other end of which is attached to a shift knob (4). 1t also has 'I
provision to hold one end of the boot.
I I
I-lere the lever konstitutes a single piece on which the knob is assembled by
me,ans of snap joint or threaded joint.
In ,case of snap fit type knob, plastic over molded lever rod is inserted into
female part within the knob. In case of threaded knob, 'knob with. internal
threads is. locked with external threads of the lever rod. The method of
assembling the bo.o . t to the knob depends on the snap or threaded joint.
The current configuration has following shortcomings:
. 1. Fixed lever ratio as length of the lever is fixed with no other provision
, to vary the lever ratio. . .
2. In case of threaded joint between lever rod and knob, the assembly of
knob is not possible at vehicle assembly line as knob is required to be
. .
assembled at supplier end only:.
3: Only one type of boot can be used for any knob-boot configuration.i.e.
rubber boot for threaded knob and leather boot for snap fit knob.
4. Limitationto the serviceability of the knob e.g. in case of threaded
knob, the whole GSLA needs to be replaced and. in case of snap type
knob, the knob replacement is possible for only a limited number of
times.
5. Difficulty in the knob removal in case of snap fit knob' as very high
load is required to dismantle the knob. Also in case of threaded knob
, the knob removal is not possible at all, which requires replacement of
whole Gear Shift Lever Assembly. . .
Some prior publication/patent may be discussed hereinunder:
CN203093742(U):- It pertains a gear shifting device with a changeable lever
ratio, which comprises a gear selecting and shifting armmovably arranged on a
gear shifting lever and is fixed by a fastening means. The fastening means
includes .a threaded section in the lever and also in the arm.
According to another disclosure a gear shift lever is provided for effecting a gear
ratio change by manipulation of the lever. The gear shifting lever with
changeable rod.ratio comprises an elongated main portion connected by spaced I
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leaf springs with a handle movable relative to the main portion and a hall effect
, - sensor for detection of movements on the handle .
This prior art forms an electromechanical system, which is complicated and
expensive.
In order to overcome shortcomings of the aforesaid know arts, the present
invention has been proposed, which can serve the purpose effectively with ease
and cost effectiveness.
OBJECTS OF THE INVENTION
An object.of this invention is to propose a gear shifter assembly with variable
lever ratio for vehicle to vary lever ratio as per need of user.
Another object of this invention is to propose a .gear shifter assembly with
variable lever ratio for vehicle having flexibility of using any lype of boot.
Further object of' this invention is to propose a gear shifter assembly with
variable lever ratio for vehicle which enables replacement of boot multiple times
without requiring to replace the knob.
Yet another object of this invention is to propose a gear shifter assembly with
variable lever ratio for vehicle which facilitates assembly.
SUMMARY OF INVENTION ,
~cco;din~to this invention there is provided a gear' shifter assembly with
variable lever ratio for a vehicle comprising a gear knob having. a centrally
placed .tubular section with a lug to be engaged in a guide of lever rod so .as to
set lever ratio according to requirement.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Further objects and advantages of this invention will be more apparent from
the ensuing description when read in conjunction with the accompanying
drawings of exemplary embodiments of invention and wherein:
Fig. 1 shows: Gear shift lever assembly according to prior art.
Fig. 2 shows: Conventional lever rod and knob.
Fig. 3 shows: .Gear knob and lever rod according to present invention prior to
assembly. . .
Fig. 4 shows: Gear knob and lever rod of invention following assembly.
DETAIL DESCRIPTION OF THE INVENTION WITH REFERENCE TO THE
ACCOMPANYING DRAWINGS
The present invention makes a.disclosure in respect. of gear shifter assembly
with variable lever ratio for a vehicle.
In this regard, reference may be. made to fig 3 . The gear shifter assembly
includes a non metallic knob (1A) constituting a single piece preferably made of
resin having a centrally placed tubular section (2A). The tubular section at the
center of the knob accommodates .a spring (3A), preferably a torsional
compression spring. The tubular section is integral to a lug (4A) adjacent to the
spring .maintaining a clearance therefrom for uninterrupted linear movement of
the spring through the tubular section during change of lever ratio.
HPO DEbHI 1 4 - 1 0 - 2 8 1 5 ,168 1 0 7
Further, in accordance with the present invention, top surface of the lever rod
(5A) is provided with a groove (6A) which forms resting surface for the spring .
while changing the lever ratio.
.In addition to the abov,e, there is provision of a guide on the lever rod. Said .
guide comprises a longitudinal slot (7A) in longitudinal direction of the rod.
Said slot connects the groove at one end. Further, the longitudinal slot is
connected to a plurality of slots (8A) in the transverse direction of the rod. The
transverse slot is ,having substantially a L-section as illustrated.
The guide on lever rod guides and locks the lug at different positions on the rod
as per need of user i.e. H,M and L where H refers to highest lever ratio, M refers
to medium and L refers to lowest lever .r a. tio.
. .
In order to set the knob at a particular position, the knob is pushed along the
guide (longitudinal slot) on the lever rod and thereafter rotated to a particular
position through transverse slot and released. The spring provides the required
force so that the lug cannot pop out of the locking slot during gear shifting
operation.
Following assembly the knob is engaged with the lever rod as shown in the fig 4
reflecting the lug in locked position.
Thus, the gear knob of invention is fitted by a spring-slot mechanism instead of
conventional snap .or threaded joint. This enables usage of various types of
knobs. for both rubber and leather boots. Further, the user can conveniently
set the lever ratio by engaging the knob at different positions of , sl.o t i.e. L, M. H
as described hereinabove.
Advantageous Features
- Availability of. multiple lever ratios enabling user to select lever ratio as,
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I per choice, which' in turn reduces/increases the gear shifting effort as
per user's will.
. - Elimination of threaded joint and snap joint which gives rise the
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.. flexibility of implementing any type of boot i.e. leather and rubber.
I 1 Enabling serviceability of thi knub/boot. e.g. in case of damage to
knob/boot, only damaged part needs t'o be substituted in lieu olentire
lever assembly.
1 - Facilitates knob removal, which can be carried out any number of times
I with ease.
I - Damp the vibration on the knob-w. h. ichg ets transferred from, engine room.
. .
, .
It is to be noted that the present invention is susceptible to modifications,
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adaptations and changes by those skilled in the art. Such variant embodiments
employing the concepts and features of this invention are intended to be within
the scope of the present invention, which is. further set forth' under th.e
following claims:-

WE CLAIM:
1. A gear shifter assembly with variable.lever ratio for a vehicle comprising
a gear knob having a centrally placed tubular section with a lug to be ,
engaged in a guide of lever rod so as to set lever ratio according to
require~lleril.
2. A gear shifter assembly with variable lever ratio' for a vehicle as claimed
. in claim 1 wherein the gear knob comprises a non metallic knob
constituting a single piece, the tubular section of which accommodates a
spring such as torsional Compression spring.
3. A gear shifter assembly with variable lever ratio for a vehicle as claimed
in claim 1 or 2 wherein the tubular section is integrated to said lug
4
adjacent to the spring maintaining a gap therebetween.
4. A gear shifter assembly with variable lever ratio for a vehicle as claimed
in any of the proceeding claims wherein the lever rod is provided with a
groove on top surface thereof forming a resting surface for said spring
during changing the lever ratio.
5. A gear shifter assembly with variable lever ratio for a vehicle as claimed
in any of the proceeding. claims wherein said guide comprises a
longitudinal slot in longitudinal direction of the rod, which connects the
groove at one end.
6. A gear shifter assembly with variable lever ratio for a vehicle as claimed
in any of the proceeding claims wherein the longitudinal slot is provided
in .connection with multitude of slots in transverse direction of the rod.
7. A gear shifter assembly with variable lever ratio for a vehicle as claimed
in any 'of the proceeding claims wherein the slots in transverse direction
are having a substantially L-section.
8. A gear shifter assembly with variable lever ratio for a vehicle as claimed
in any of the proceeding claims wherein the transverse slots are provided
to set the lever ratio at the highest, medium and lowest position by
I engaging said lug in the respective slot. of the guide.
9. A gear shifter'assembly with variable lever ratio for a vehicle as claimed
in any. of the preceding claims is associated with the advantageous
features such as herein described.
10. A gear shifter assembly with variable .lever ratio for a
vehiclesubstantially as herein described , with reference to the
accbmpanying drawings.