FORM 2
THE PATENTS ACT 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
PROVISIONAL SPECIFICATION
(See Section 10; rule 13)
TITLE OF THE INVENTION
"STEERING COLUMN TILT MECHANISM" APPLICANT
TATA MOTORS LIMITED, an Indian company
having its registered office at Bombay House,
24 Homi Mody Street, Hutatma Chowk,
Mumbai 400 001 Maharashtra, India
INVESTORS
Milind Bhatambarekar
All 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 describes the invention
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FIELD OF INVENTION
The present invention relates to steering column tilt mechanism. BACKGROUND
Steering column tilt mechanism allows simple, quick and convenient adjustment of a steering wheel in a plurality of positions. Steering column can be tilted by operating a pawl lever. The pawl lever is functionally coupled to the gear and pinion of the steering column. By the operation of the pawl lever the gear and pinion of the steering column gets disengaged and the steering column can be tilted. The steering column can be fixed at the desired position and gets locked after release of the pawl lever. For the tilting operation the pawl lever has to be rotated by 180 degrees. The Steering column tilt mechanism allows the steering wheel to be placed at any one of a plurality of positions located along the arcuate path. Once the steering wheel is at the desired position, the lever is returned to the original position to lock the column at that position.
As size of dash board occupies more space, free space available for rotation / operation of the pawl lever will be less. In such case rotation angle of 180 degrees of the pawl lever for disengagement of the gear and pinion is not possible due to inadequate space.
OBJECTS OF THE INVENTION
An object of the present invention is to decrease the rotation angle of a pawl lever.
Another object of the present invention is to provide easy tilting of steering column.
Yet another object of the present invention is to provide a cam to reduce the rotation angle of a pawl lever.
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Further object of the present invention is to provide a steering column tilt mechanism to accommodate less space.
Still further object of the present invention is to provide a steering column tilt mechanism to accommodate dash board space constraint.
The invention is described with reference to the embodiments given hereinafter. It may however be understood that the embodiments only by way of example and that the invention may be exemplified in many other ways obvious to a person skilled in the art. BRIEF DESCRIPTION OF DRAWING
Figure 1 shows pictorial view of pawl and lever mechanism embodying present invention.
Figure 2 shows pictorial view of cam mechanism embodying present invention.
Figure 3 shows pictorial view of pawl and lever mechanism with its location embodying present invention.
Figure 4 shows pictorial view of the cam profile of the steering column embodying the present invention.
Figure 5 shows pictorial view of connection of pawl and lever embodying present invention.
Figure 6 shows pictorial view of connection of pawl and lever in another view embodying present invention.
Figure 7 shows pictorial view of gear mating position embodying present invention. DRAWINGS- REFERENCE NUMERALS
202- Pawl lever (locking position)
204- Progressive cam
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206- Pawl
208- Holding bracket
210- Pawl lever (unlocking position)
212-Rachet
214- Tension spring
216-Bracket
218- Mounting bracket
220- Boss
222- Holding bracket
224- Boss for combo switch
226- Rod
228- Steering spindle top
230- Gear mating position
DESCRIPTION
In the present invention cam profile of progressive cam 204 of steering column tilt mechanism is redesigned as shown in figure 4. In the present invention a pawl lever 202 is functionally coupled to the cam 204. The contour of the cam 204 when actuated by the pawl lever 202 controls engagement and disengagement of gear and pinion. The contour of the cam 204 is made in such a way that the pawl lever needs to be rotated by 60 degrees max for disengagement of the gear and pinion. Positive locking is provided on the pawl 206 and the cam 204.
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It is reiterated that the present invention is not limited to the above embodiments. Various other embodiments of the invention will be apparent to a person skilled in the art or follow from routine experimentation.
Dated this 18th Day of June 2007
To
The Controller of Patents
The Patent office at Mumbai
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