FORM 2
THE PATENTS ACT 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION (See Section 10; rule 13)
TITLE OF THE INVENTION Parking Brake Mechanism in Vehicle Dashboard Console
APPLICANTS
TATA MOTORS LIMITED, an Indian company
having its registered office at Bombay House,
24 Homi Mody Street, Hutatma Chowk,
Mumbai 400 001 Maharashtra, India
INVENTOR Sivaprakash R, G H N V Druga Prasad
Indian national
of TATA MOTORS LIMITED an Indian company
having its registered office at Bombay House,
24 Homi Mody Street, Hutatma Chowk,
Mumbai 400 001 Maharashtra, India
PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the invention and the manner
in which it is to be performed

FIELD OF INVENTION
The present invention relates to parking brake control mechanism more particularly to mechanically operate parking brake that can be packaged in vehicle dashboard console, for holding the vehicle stationary when parked.
BACKGROUND OF INVENTION
Parking brake mechanism for use on vehicle normally includes a hand-actuated brake. Conventionally this hand-actuated brake is mounted on floor in between driver and co-driver. The parking brake mechanism uses ratchet and pawl mechanism and is mounted on the floor. A switch is used to give signal to the driver about the parking brake engagement condition. One end of pull rod is riveted to hole and equalizer is fitted to the other end of the pull rod. From equalizer two cable splits and are fitted to the LH and RH rear brake.
When the driver want to apply parking brake he has to press the push button and simultaneously he has to rotate the lever to pull the pull rod and the brake is applied at the rear. As the driver releases the push button the pawl gets locked with the ratchet. To release the parking brake the driver has to pull the lever and he has to press the push button so that the pawl is free from ratchet and the lever is rotated to its original position.
This parking brake can be mounted only on floor between driver and co-driver because of engineering and packaging constraints. Hence the space between driver and co-driver is not effectively utilized for Utility package. Though there is an option of Electric parking brake but it is expensive, and has its own limitations.
OBJECT OF THE INVENTION
The main object of the invention is to obviate the above mentioned drawbacks.

Another object of the invention is to develop a parking brake mechanism that can be packaged in vehicle dashboard console.
Yet another object of the invention is to design a parking brake mechanism by incorporating the dog clutch principle so that it is compact enough to package in vehicle dashboard console.
SUMMARY OF THE INVENTION
The embodiments herein provide a parking brake control mechanism in vehicle dashboard. The mechanism comprises a base component with at least three mounting legs towards outer side and a shaft towards inner side. The shaft includes a shaft hole at its end. A switch is connected to a switch mounting bracket in said base component. A rachet having a hole and a notch is connected to said shaft in said base component, said rachet is followed by a spacer and a bush bearing. A pawl disc having a shaft is followed by said spacer and bearing and is inserted through said shaft. The pawl disc includes a guide, pawl disc hole, cable hole, and an interference means. A lever handle disc is inserted over said pawl disc shaft by interference means with a corresponding interference means in said pawl disc towards one end and the other end of the lever handle disc is locked at shaft hole to complete the lever handle sub assembly. A vertical link extends between said lever handle disc and lever handle. The vertical link includes a plurality of cut out and mounting points. A pawl is riveted on the pawl disc hole for rotating about its pivot axis. A pull wire passing through said guide in said pawl disc is connected to one end of said pawl and other end is connected to a release mechanism inside said handle grip. A push button is assembled at other end of release mechanism and then the lever handle grip is assembled over it.
According to present invention, during rotation of the lever handle grip the subassembly gets rotated and said pawl sweeps over the notches of ratchet as a result the lever handle disc and pawl disc rotates as single unit without slippage. The sub

assembly is inserted over the bush, which acts as a bearing for rotation over shaft. The washer is inserted in to said shaft and the spit pin is inserted in said shaft hole to lock the lever handle disc. To hold vehicle in stationary position said lever handle grip is pulled and then the driver has to release the lever handle grip, at this position the pawl gets locked with the ratchet and keeps the lever in stationary position.
In order to release the parking brake, the driver has to hold the lever handle grip and by pulling it, the push button has to be pressed. The release assembly converts the push action in to pull action, this disengages the pawl and ratchet contact and allows the sub assembly to rotate to its original position. The pawl disc is riveted to pawl disc cable hole and an equalizer is attached to other end of cable from which two cable splits and are fitted to the left hand and right hand rear brake. The pawl disc hole is pulled in opposite direction to that of the rotation of the lever handle grip to hold vehicle in stationary position. The mounting points are provided in said vertical link to hold a pull wire running between said pawl and lever handle. The pawl disc includes a plurality of projections for interference fit with corresponding plurality of projections in said lever handle disc. A flap is connected to the pawl disc for actuating said switch and for providing signal to the driver about the parking brake engagement condition. A gear shifter 27 is mounted on a bracket or parking brake operating envelope 28 in said dashboard.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be more completely understood by reference to the following detailed description of a preferred embodiment of the present invention when read in conjunction with the accompanying drawing, in which:
FIG. 1 is an elevated perspective view of the conventional parking brake mechanism.

FIG. 2 is an elevated view of prior art showing the parking brake actuation. Position 1 shows the parking brake in released condition and Position 2 shows the parking brake in applied condition. Arrow 1 shows the parking brake lever handle pull direction and Arrow 2 show the pull rod (not shown in Fig.) pull direction.
FIG. 3 is an exploded view of prior art.
Fig. 4 is an elevated perspective view of instant invention, which shows the Parking brake mechanism in assembled condition that can be packaged in Vehicle dash board.
Fig. 5 shows the elevated perspective view of parking brake, showing its actuation. Position 3 shows the parking brake in released condition and Position 4 shows the parking brake in applied condition. Arrow 3 shows the parking brake lever handle pull direction and Arrow 4 show the pull cable (not shown in Fig.) pull direction.
Fig. 6 shows the exploded view of parking brake.
Fig.7 shows the invented parking brake assembly packaged in the vehicle dashboard console.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings wherein the showings are for the purpose of illustrating a preferred embodiment of the invention only, and not for the purpose of limiting the same.
Parking brake mechanism for use on vehicle normally includes a hand-actuated brake. Conventionally this hand-actuated brake is mounted on floor in between driver and co-driver as shown in Figure '1', '2' and '3'. The parking brake mechanism as illustrated in Fig. '1' is simple ratchet and pawl mechanism, where the ratchet 1 together with the mounting bracket 2 is a single component as shown in Fig

'3' which is mounted on the floor. The lever 3 which is riveted 9 to the mounting bracket 2, can rotate about the rivet hole 9a. Pawl 4 and push rod 5 shown in Fig. 3, where the later is assembled inside the lever 3 and the pawl 4 is riveted 9 to the lever 3 at rivet hole 9b, as the lever rotates the pawl sweeps over the ratchet 1. The Push button 6 (refer Fig. '3') is used to operate the push rod 5 for actuating the pawl 4. The switch 7 (refer Fig. '3') is fixed to the switch mounting bracket 8 which in turn welded on the mounting bracket 2. A flap 9c on lever 3 is to actuate the switch 7. This switch is used to give signal to the driver about the parking brake engagement condition. One end of pull rod (not shown in Fig.) is riveted to hole 10 and equalizer (not shown in Fig.) is fitted to the other end of the pull rod (not shown in Fig.). From equalizei two cable splits and are fitted to the LH and RH rear brake.
At initial condition i.e. before applying parking brake, the lever is in position 1 (refer Fig. '2'). When the driver want to apply parking brake he has to press the push button 6 and simultaneously he has to rotate the lever 3 to pull the pull rod (not shown in Fig.) and hence the brake is applied at the rear. As the driver releases the push button 6 the pawl 4 gets locked with the ratchet 1 and the lever stops in the position 2 (refer Fig. '2'). To release the parking brake the driver has to pull the lever 3 and he has to press the push button 6 so that the pawl 4 frees the ratchet 1 and the lever is rotated to its original position 1. The position 2 is parking brake engaged condition and position 1 is in disengaged condition.
The customers are delighted if the newer passenger car is provided with more/newer utility provision, so it is required to maximize the utility package in the passenger car. As said this parking brake can be mounted only on floor between driver and co-driver. If the parking brake is relocated from this position, then this space between driver and co-driver can be effectively utilized for Utility package. There is option of Electric parking brake which is expensive, so a new parking brake that can be package in vehicle dashboard console is required. To full fill this requirement a new parking brake is proposed.

Now referring to Fig. 4, there is an elevated perspective view of a parking brake mechanism embodying the principles of the present invention. Refer Fig. 6 for exploded view of the parking brake mechanism of this invention. The following description will be with reference to the Fig. 6 in assembly sequence. The shaft 13 is the base component with three mounting legs. The ratchet is case hardened steel assembled at 13a of shaft 13, the ratchet is being welded at this position. The spacer 15 is then inserted, followed which the Bush 16 is inserted which acts as bearing. The pawl 19a is riveted 19b on the pawl disc hole 17a, so that this can rotate about this pivot. The Lever handle disc 20 is inserted over the pawl disc shaft 17b, in such a way that pawl disc projection 17e, 17f gets locked in between the Lever handle disc projection 20b, 20c, 20d, 20e by means of interference fit, i.e., the lever handle disc 20 and pawl disc 17 rotates as single unit without slippage. This sub assembly 26 is inserted over the bush 16 with interference. As the bush 16 acts as bearing, this subassembly 26 (pawl disc 17, pawl 19a and lever handle disc 20) can rotate over the shaft 13. The washer 18 is inserted in to the shaft 13 and the spit pin 18a inserted in shaft hole 13 c. One end of the pull wire 19 is assembled with release mechanism assembly 22. This release mechanism assembly 22 is assembled inside the Lever handle 21 and the other end of the pull wire is assembled to the pawl 19a passing through guide 17c. Push button 23 is assembled at other end of release mechanism and then the lever handle grip 24 is assembled.
Fig. 5 shows the parking brake actuation. At initial condition i.e. before applying parking brake the lever is in position 3 (refer Fig. s5'). When the driver wants to apply parking brake he has to hold the Lever handle grip 24 and by pressing the push button 23 it should be rotated. During rotation of the lever handle grip 24, the subassembly 26 (pawl disc 17, pawl 19a and lever handle disc 20) gets rotated; due to this the pawl 19a sweeps over the notches 14a of ratchet 14. The dog clutch principle works over here during this rotation, the lever handle disc 20 and the pawl disc 17 never gets slipped and rotates as a single unit. This rotation is by means of

interference fit of projections in the lever handle disc 20 and pawl disc 17 and not by friction. After enough pull of the lever handle grip 24 to hold the vehicle stationary, the driver releases the Lever handle grip 24. At this position the pawl 19a gets locked with the ratchet 14 and keeps the lever in position 4 (refer Fig. '5'). To release the parking brake the driver has to hold the lever handle grip 24 and by pulling it, the push button 23 has to be pressed. The release mechanism assembly 22 converts the push action in to pull action; this disengages the pawl and ratchet contact and allows the sub assembly (lever handle disc, pawl disc, and pawl) to rotate to its original position. During the rotation of the Lever handle grip 24 in the direction shown by arrow 3 (Refer Fig '5'), the pawl disc cable hole 17d is pulled in the direction as shown by arrow 4. A cable (not shown in Fig.) is riveted to pawl disc cable hole 17d and a equalizer (not shown in Fig.) is attached to other end of cable (not show in Fig.) from which two cable splits and are fitted to the LH and RH rear brake. The switch 25 (refer Fig '6') is fixed to the switch mounting bracket 13b which in turn welded on the shaft disc 13d. A flap 17g is welded to the Pawl disc 17 is for actuating the switch 25. This switch is used to give signal to the driver about the parking brake engagement condition.
Fig. 6 shows the perspective view of Invented parking brake mechanism packaged in the Vehicle dashboard console. The dashboard 31 and steering wheel 32 is mounted to the vehicle cross car beam (not shown in Fig.).The Gear shifter 27 is mounted on bracket inside dashboard console 28. The parking brake operating envelope i.e. In released condition 29 and in applied condition 30 is packaged in the vehicle dashboard console 28.
Advantages
• The parking brake mechanism according to present invention is packaged in vehicle dashboard console to utilize the space between the front driver and passenger.

• The parking brake mechanism employs doc clutch principle and is compact enough to be packaged in vehicle dashboard console.
The foregoing description is a specific embodiment of the present invention. It should be appreciated that this embodiment is described for purpose of illustration only, and that numerous alterations and modifications may be practiced by those skilled in the art without departing from the spirit and scope of the invention. It is intended that all such modifications and alterations be included insofar as they come within the scope of the invention as claimed or the equivalents thereof.

We claim
1. A parking brake control mechanism provided in vehicle dashboard, comprising;
a base component 13d with at least three mounting legs towards outer side and a
shaft 13 towards inner side, said shaft having a shaft hole; a switch 25 is connected
to a switch mounting bracket 13b in said base component 13d.
a rachet having a hole and a notch is connected to said shaft 13 in said base
component, said rachet is followed by a spacer and a bush bearing;
a pawl disc 17 having a shaft 17b and a hole is followed by said spacer and bearing
and is inserted through said shaft 13, said pawl disc having a guide 17c, pawl disc
hole 17a, cable hole 17d, and an interference means (17e and 17f);
a lever handle disc 20 is inserted over said pawl disc shaft 17b by interference
means with a corresponding interference means in said pawl disc 17 towards one end
and the other end of the lever handle disc 20 is locked at shaft hole 13c to complete
the lever handle sub assembly 26;
a vertical link 20a extends between said lever handle disc 20 and lever handle 21,
said vertical link having plurality of cut out and mounting points();
a pawl 19a is riveted (19b) on the pawl disc hole 17a for rotating about its pivot axis;
a pull wire 19 passing through said guide 17c in said pawl disc 17 is connected to
one end of said pawl 19a and other end is connected to a release mechanism inside
said handle grip 24;
a push button 23 is assembled at other end of release mechanism and then the lever
handle grip 24 is assembled over it.
2. The parking brake mechanism according to claim 1, wherein during rotation of the lever handle grip 24 said subassembly gets rotated and said pawl 19a sweeps over the notches 14a of ratchet 14 as a result said lever handle disc 20 and pawl disc 17 rotates as single unit without slippage.

3. The parking brake mechanism according to claim 1, wherein said sub assembly 26 is inserted over said bush 16 which acts as a bearing for rotation over shaft 13.
4. The parking brake mechanism according to claim 1, wherein a washer 18 is inserted in to said shaft 13 and the spit pin 18a inserted in said shaft hole 13c to lock the lever handle disc.
5. The parking brake mechanism according to claim 1, wherein to hold vehicle in stationary position said lever handle grip 24 is pulled and then the driver has to release the lever handle grip 24, at this position the pawl 19a gets locked with the ratchet 14 and keeps the lever in stationary this position.
6. The parking brake mechanism according to claim 1, wherein to release the parking brake the driver has to hold the lever handle grip 24 and by pulling it, the push button 23 has to be pressed, the release mechanism assembly 22 converts the push action in to pull action; this disengages the pawl and ratchet contact and allows the sub assembly to rotate to its original position.
7. The parking brake mechanism according to claim 1, wherein said pawl disc is riveted to pawl disc cable hole 17d and a equalizer is attached to other end of cable from which two cable splits and are fitted to the left hand and right hand rear brake.
8. The parking brake mechanism according to claim 1, wherein during the rotation of the lever handle grip 24 to hold vehicle in stationary position said pawl disc cable hole 17d is pulled in opposite direction.
9. The parking brake mechanism according to claim 1, wherein said mounting points are provided in said vertical link to hold a pull wire running between said pawl and lever handle.

10. The parking brake mechanism according to claim 1, wherein said rachet 14 is case hardened steel which is welded with shaft of said base component ratchet.
11. The parking brake mechanism according to claim 1, wherein said pawl disc 17 having a plurality of projections (20b, 20c, 20d, 20e) for interference fit with corresponding plurality of projections (17e, 17f) in said lever handle disc.
12. The parking brake mechanism according to claim 1, wherein a flap 17g is connected to said pawl disc 17 for actuating said switch 25 and for providing signal to the driver about the parking brake engagement condition.
13. The parking brake mechanism according to claim 1, wherein a gear shifter 27 is mounted on a bracket or parking brake operating envelope 28 in said dashboard.