|Title of Invention
STOPPER GEAR SHIFT CAM
|This invention relates to an improvement on stopper gearshift cam. The device incorporates a specific shape of the stopper gearshift cam that offers highest resistive force or damphing force to the cam gearshift oscillations at the start of the oscillations itself, thereby by avoiding the un-desirable gearshift on its own. All this without an increase in the gear shifting force.
Field of Invention
This invention in general relates to auto mobile. In particular this invention relates to scooter type motor cycle. The present invention relates to "An improvement on Stopper gearshift cam" used on motorcycles. State of Art
Stopper gearshift cam is an essential part of all foot operated geared motorcycles. This is employed to retain the Cam gearshift in the intended gear position i.e., Neutral or 1st or 2nd or 3rd or 4th or 5th etc. The Cam gearshift is retained in each indexed position by the Stopper gearshift cam, which has a tension spring or a torsion spring. One of the known types of Stopper gearshift cam is the plate type, which has a specific shape on which the cam roller pins slide. Each time the rider intends to shift the gear, the Cam gearshift has to index through predetermined angle. Under dynamic conditions when the gears are rotating at higher speeds, the Cam gearshift tends to oscillate which amplifies due its own inertia. If this inertia f exceeds the retaining force of the Stopper gearshift cam and Spring, the Cam gearshift indexes on its own, shifting the gear to neutral or to the next gear. Such un-intended gearshift is both undesirable to the rider as well as to the safety of gearbox. One countermeasure is to increase the spring force of Stopper gearshift cam spring. However this has the negative effect of increasing the gearshift force that can be felt by the rider while shifting gears and hence may not be acceptable to the customers.
Many device are already known in the art. However the known device suffer from various drawbacks.
Accordingly what is needed in the art is an improvement that overcomes the above mentioned deficiencies of the prior art.
It is to be noted that the prior art description give in detail information of the technology, method, process and device known in the art. It explain the deficiency in the related art and the object of the invention being to overcome or surmount the problem
associated with the prior art. This forms the essential feature and the object of the invention.
SUMMARY OF INVENTION
The inventors have made great effort to provide a device which meet the requirement of the industry and overcome the problem associated in the prior art.
To achieve the above object according to first aspect and feature of the present invention there is provided a device to improve, efficiency,.
According to second aspect and feature of the invention in addition to the first feature the invention comprises a device which is unique, rugged efficient, economical
At the outset of the description which follows it is to be understood that ensuring description only illustrate a particular from of this invention. However, such particular form is only an exemplary embodiment without intending to imply any limitation on the scope of this invention. Accordingly, the description is to be understood as an exemplary embodiment and reading of the invention is not intended to be taken restrictively.
The above and other objects features and disadvantages will be clear from the following description of preferred embodiment taken in conjunction with accompanying drawings.
The foregoing description is outlined rather broadly preferred and alternative feature of the present invention so that those skilled in the art may better understand the detailed description of the invention that follows. Additional features of the invention will be described hereinafter that form the subject of claims of the invention. Those skilled in the art should appreciate that they can readily use the disclosed conception and specific embodiment as a basis for designing and modifying other structures for carrying out the same purposes of the present invention. Those skilled in the art should realize
such equivalent conception do not depart from the spirit and scope of the invention in its broadest form.
An improvement on stopper gearshift cam incorporating a specific shape of the stopper gearshift cam that offers higher resistive force or damping force to the cam gearshift oscillations at the start of the oscillations itself, there by avoiding the undesirable gearshift on its own, all this without an increase in the gear shifting force.
The accompanying drawing is intended to provide further understanding of invention and is incorporated in and constitute a part of invention. The drawings illustrate an embodiment of invention and together with the description illustrate principle of invention.
The drawings should not be taken as implying any necessary limitation on the essential scope of invention.
The drawings are given by way of non-limitative example to explain the nature of the invention.
For a more complete understanding of the instant invention reference is now made to the following description taken in conjunction with accompanying drawings.
The various feature of novelty which characterise the invention are pointed out specifically in the claims which a part of description. For a better understanding of the invention, its operating advantage, specific objects obtained by its use, reference should be made to the drawings and descriptive matter is which there are illustrated and described preferred embodiments of invention.
This invention relates to the design modification to the specific shape of the Stopper gearshift cam that offers higher resistive force or damping force to the Cam
gearshift oscillations at the start of the oscillations itself, there by avoiding the undesirable gearshift on its own. All this without an increase in the gear shifting force;
The invention will now be explained with reference to the following drawings.
Statement of Figures of Drawings
Referring now to drawings, where like numerals designate identical or corresponding parts throughout the referred views.
Figure 1 is a side view of a typical engine gear box assembly of motorcycle on which the Stopper gearshift cam of the,proposed invention is used
Figure 2 is the schematic arrangement of the Stopper gearshift cam of present design
Figure 3 is the schematic arrangement of the Stopper gearshift cam of the proposed
Detailed Description of an embodiment of invention
Referring to Figure 1, the Cam gearshift C is held between the Crankcase L and R of an engine gearbox assembly. Five Roller pins P are provided on the right side of the Cam gearshift C (Refer Section A -A). These five Roller pins P facilitate the rotation of the Cam gearshift C through a known type of Pawl W and Shaft gearshift S mechanism. The five Roller pins P are retained in the axial direction by Retainer plate R.A Stopper gearshift cam S retains the indexed position of Cam gearshift C. The Stopper gearshift cam S hinged at H rests on two of the Roller pins P under tension of the spring G.
During the indexing of the Cam gearshift C for changing the gears, any two of the roller pins P has to slide on the Stopper gear shift cam S profile defined as "a, b,c,d,e" (Refer Figure 2)
In the schematic diagram shown in Figure 2 the Stopper gearshift cam S profile "a" to "e" of the current design is shown on which the roller pins P has to slide.
In the schematic diagram given in Figure 3, the Stopper cam gearshift profile "a" to "e of the proposed invention is shown on which the roller pins P has to slide.
The invention has been explained in relation to specific embodiment. It is inferred that the foregoing description is only illustrative of the present invention and it is not intended that the invention be limited or restrictive thereto. Many other specific embodiments of the present invention will be apparent to one skilled in the art from the foregoing disclosure. All substitution, alterations and modification of the present invention which come within the scope of the following claims are to which the present invention is readily susceptible without departing from the spirit of the invention.
The scope of the invention should therefore be determined not with reference to the above description but should be determined with reference to appended claims along with fiiU scope of equivalents to which such claims are entitled.
1. An improvement on stopper gearshift cam wherein the said device incorporates a
specific shape of the stopper gearshift cam that offers higher resistive force or
damping force to the cam gearshift oscillations at the start of the oscillations
itself, there by avoiding the un-desirable gearshift on its own, all this without an
increase in the gear shifting force.
2. An improvement on stopper gearshift cam as claimed in claim 1 wherein the cam
gearshift is held between the crankcase and of an engine gearbox assembly, five
roller pins are provided on the right side of the cam gearshift, these five roller pins
facilitate the rotation of the cam gearshift through a known type of pawl and
shaft gearshift mechanism, the five roller pins are retained in the axial direction
by retainer plate, a stopper gearshift cam retains the indexed-position of cam
gearshift, the stopper gearshift cam hinged at rests on two of the roller pins
under tension of the spring.
3. An improvement on stopper gearshift cam as claimed in claim 1 wherein During
the indexing of the cam gearshift for changing the gears, any two of the roller pins
has to slide on the stopper gear shift cam profile defined as "a, b,c,d,e",
4. An improvement on stopper gearshift cam as claimed in claim 1 wherein the
stopper gearshift cam profile "a" to "e" of the current design is shown on which
the roller pins has to slide.
5. An improvement on stopper gearshift cam as claimed in claim 1 wherein the
stopper cam gearshift profile "a" to "e" of the proposed invention is shown on
which the roller pins has to slide.
6. An improvement on stopper gearshift cam as described in the complete
specification and as illustrated by way of drawings accompanying the complete
|Indian Patent Application Number
|PG Journal Number
|Date of Filing
|Name of Patentee
|TVS MOTOR COMPANY LIMITED,
|1956 JAYALAKSHMI ESTATES #8, HADDOWS ROAD, CHENNAI-600 006
|PCT International Classification Number
|PCT International Application Number
|PCT International Filing date