Title of Invention	A GEAR SHIFTING DEVICE FOR A THREE WHEELED MOTOR VEHICLE
Abstract	A gear shifting device for a three wheeled motor vehicle comprising lugs on the face of the transmission gears, engaged by axial movement of forks; a cam drum for moving the gears axially said drum having grooves of predetermined shapes with which projections provided on the said fork engage; a set of reduction gears for rotating the cam drum; a driven gear being fixed to one end of the cam drum to engage with a drive gear; a shaft parallel to the cam drum axis, the drive gear being fixed at one end of the said shaft; a pulley fixed at the other end of the said shaft, said pulley being connected through a cable to a second pulley provided on the handle bar grip of the said vehicle. (Figure 1)

Title of Invention

A GEAR SHIFTING DEVICE FOR A THREE WHEELED MOTOR VEHICLE

Abstract

A gear shifting device for a three wheeled motor vehicle comprising lugs on the face of the transmission gears, engaged by axial movement of forks; a cam drum for moving the gears axially said drum having grooves of predetermined shapes with which projections provided on the said fork engage; a set of reduction gears for rotating the cam drum; a driven gear being fixed to one end of the cam drum to engage with a drive gear; a shaft parallel to the cam drum axis, the drive gear being fixed at one end of the said shaft; a pulley fixed at the other end of the said shaft, said pulley being connected through a cable to a second pulley provided on the handle bar grip of the said vehicle. (Figure 1)

Full Text	This invention relates to a gear shifting device for a three wheeled motor vehicle, more particularly to a three wheeled vehicle provided with a handle bar for steering control and gear shifting. In any known type of three wheeled vehicle provided with a handle for steering, gear changing or shifting is achieved by rotating handle bar grip to a predetermined angle, which is attached to a pulley. This in turn rotates another pulley through a cable, which is mounted on the engine gear box cover. The pulley provided in the engine gear box cover moves a shifter star having lugs through a push rod into the desired gear slot provided on the respective gears. For example, if the first gear speed is to be attached, then lug on shifter star will be moved into slot of first gear driven. Thus the shifter star will be operating all the gears at all times during gear shift. This continuous operation leads to wear and tear of lugs causing improper/abrupt gear shifting over a period of time causing inconvenience to the rider from point of view of riding, serviceability and maintainability. Hence the objective of the invention is to provide a gear-shifting device for three wheeled vehicles having handle bar math steering, which will give smooth gear shifting at all times, high reliability and low maintenance. This invention will now be described with reference to the accompanying drawings, which illustrate, by way of example, and not by way of limitation one of possible embodiments of this invention. Fig, I illustrating the gear box Fig. 2 illustrating section of gear-shifting arrangement. And Fig.3 illustrating the handle bar of the vehicle. In the proposed gear shifting mechanism, the shifting is obtained m the gear box 1 through lugs 2 provided on the face of the transmission gears 3, which are engaged by axial movement of forks 4. The number of lugs 2 provided on the face of these transmission gears 3 vary depending upon use. Conventionally, the first gear 5 and second gear 6 are used frequently compared to other gears and hence subjected to more wear and tear. Therefore the number of lugs 2 provided on these gears is greater than the number of other gears. The above mentioned gears are moved axially by a cam drum 7 which has grooves 8 of predetermined shapes with which projections 9 provided on the said fork 4 engage. The cam drum 6 is rotated by a set of reduction gears, the driven gear 10 being smaller, is fixed at one end 13 of the cam drum to engage with driver gear 12. The said drive gear being bigger is fixed at one end of shaft 13 which is parallel to the cam drum 7 axis. A first pulley 14 is fixed at the other end of the said shaft. The pulley 14 is connected through a cable 15 to another pulley 16 provided on the handle bar grip 17. Gear changing or shifting is achieved by rotating the handle bar grip 17 (attached to the pulleys 16) through a predetermined angle. This in tarn rotates said pulley 14 thoroughly the cable. The pulley 14 rotates the said drive gear, which in turn rotates the driven gear mounted on the cam drum, thus providing predetermined axial movement of the fork 4. It will be appreciated that various other embodiments of this invention are possible without departing from the scope and ambit of this invention. We Claim: 1. A gear shifting device for a three wheeled motor vehicle, comprising lugs on the face of the transmission gears, engaged by axial movement of forks; a cam drum for moving the gears axially said drum having grooves of predetermined shapes with which projections provided on the said fork engage; a set of reduction gears for rotating the cam drum; a driven gear being fixed to one end of the cam drum to engage with a drive gear; a shaft parallel to the cam drum axis, the drive gear being fixed at one end of the said shaft; a pulley fixed at the other end of the said shaft, said pulley being connected through a cable to a second pulley provided on the handle bar grip of the said vehicle. 2. A device as claimed in Claim 1 wherein the number of lugs provided on the first and second gears is greater than the number of lugs provided on the other gears. 3. A gear shifting device for a three wheeled motor vehicle substantially as herein described and illustrated with reference to the accompanying drawings.

Full Text

This invention relates to a gear shifting device for a three wheeled motor vehicle, more particularly to a three wheeled vehicle provided with a handle bar for steering control and gear shifting.

In any known type of three wheeled vehicle provided with a handle for steering, gear changing or shifting is achieved by rotating handle bar grip to a predetermined angle, which is attached to a pulley. This in turn rotates another pulley through a cable, which is mounted on the engine gear box cover. The pulley provided in the engine gear box cover moves a shifter star having lugs through a push rod into the desired gear slot provided on the respective gears. For example, if the first gear speed is to be attached, then lug on shifter star will be moved into slot of first gear driven. Thus the shifter star will be operating all the gears at all times during gear shift. This continuous operation leads to wear and tear of lugs causing improper/abrupt gear shifting over a period of time causing inconvenience to the rider from point of view of riding, serviceability and maintainability.

Hence the objective of the invention is to provide a gear-shifting device for three wheeled vehicles having handle bar math steering, which will give smooth gear shifting at all times, high reliability and low maintenance.

This invention will now be described with reference to the accompanying drawings, which illustrate, by way of example, and not by way of limitation one of possible embodiments of this invention.

Fig, I illustrating the gear box

Fig. 2 illustrating section of gear-shifting arrangement.

And Fig.3 illustrating the handle bar of the vehicle.

In the proposed gear shifting mechanism, the shifting is obtained m the gear box 1 through lugs 2 provided on the face of the transmission gears 3, which are engaged by axial movement of forks 4. The number of lugs 2 provided on the face of these transmission gears 3 vary depending upon use. Conventionally, the first gear 5 and second gear 6 are used frequently compared to other gears and hence subjected to more wear and tear. Therefore the number of lugs 2 provided on these gears is greater than the number of other gears. The above mentioned gears are moved axially by a cam drum 7 which has grooves 8 of predetermined shapes with which projections 9 provided on the said fork 4 engage.

The cam drum 6 is rotated by a set of reduction gears, the driven gear 10 being smaller, is fixed at one end 13 of the cam drum to engage with driver gear 12. The said drive gear being bigger is fixed at one end of shaft 13 which is parallel to the cam drum 7 axis.

A first pulley 14 is fixed at the other end of the said shaft. The pulley 14 is connected through a cable 15 to another pulley 16 provided on the handle bar grip 17.

Gear changing or shifting is achieved by rotating the handle bar grip 17 (attached to the pulleys 16) through a predetermined angle. This in tarn rotates said pulley 14 thoroughly the cable.

The pulley 14 rotates the said drive gear, which in turn rotates the driven gear mounted on the cam drum, thus providing predetermined axial movement of the fork 4. It will be appreciated that various other embodiments of this invention are possible without departing from the scope and ambit of this invention.

We Claim:

1. A gear shifting device for a three wheeled motor vehicle, comprising lugs on the face of the transmission gears, engaged by axial movement of forks; a cam drum for moving the gears axially said drum having grooves of predetermined shapes with which projections provided on the said fork engage; a set of reduction gears for rotating the cam drum; a driven gear being fixed to one end of the cam drum to engage with a drive gear; a shaft parallel to the cam drum axis, the drive gear being fixed at one end of the said shaft; a pulley fixed at the other end of the said shaft, said pulley being connected through a cable to a second pulley provided on the handle bar grip of the said vehicle.

2. A device as claimed in Claim 1 wherein the number of lugs provided on the first and second gears is greater than the number of lugs provided on the other gears.

3. A gear shifting device for a three wheeled motor vehicle substantially as herein described and illustrated with reference to the accompanying drawings.

Documents:

http://ipindiaonline.gov.in/patentsearch/GrantedSearch/viewdoc.aspx?id=l/gByVI+rsm+DL7D3gUENg==&loc=egcICQiyoj82NGgGrC5ChA==

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Patent Number

279350

Indian Patent Application Number

1938/CHE/2007

PG Journal Number

03/2017

Publication Date

20-Jan-2017

Grant Date

18-Jan-2017

Date of Filing

30-Aug-2007

Name of Patentee

TVS MOTOR COMPANY LIMITED

Applicant Address

JAYALAKSHMI ESTATES, NO.24 (OLD NO.8), HADDOWS ROAD, CHENNAI - 600 006

Inventors:

#	Inventor's Name	Inventor's Address
1	GNANA KOTAIAH GUTTI	RESEARCH & DEVELOPMENT, TVS MOTOR COMPANY LIMITED JAYALAKSHMI ESTATES, NO.24 (OLD NO.8) HADDOWS ROAD, CHENNAI - 600 006
2	BALAKRISHNAN SADESH	RESEARCH & DEVELOPMENT, TVS MOTOR COMPANY LIMITED JAYALAKSHMI ESTATES, NO.24 (OLD NO.8) HADDOWS ROAD, CHENNAI - 600 006
3	SIVARAMAN GOPALAKRISHNAN	RESEARCH & DEVELOPMENT, TVS MOTOR COMPANY LIMITED JAYALAKSHMI ESTATES, NO.24 (OLD NO.8) HADDOWS ROAD, CHENNAI - 600 006

PCT International Classification Number

F16H

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1			NA