FORM 2
THE PATENTS ACT 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
(See Section 10; rule 13)


TITLE OF THE INVENTION
Improved Pantograph Wiper Mechanism With Auxiliary Blade
APPLICANTS
TATA MOTORS LIMITED
An Indian company
having its registered office at Bombay House,
24 Ho mi Mody Street, Hutatma Chowk,
Mumbai 400 001 Maharashtra, India
INVENTORS
Ashfaque Ahmed Ansari, R G Rajhans,
R G Patil, A R Kale and Onkar Gorade
AH are Indian Nationals
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
This invention relates to the wiping mechanism used in vehicles and more particularly to pantograph type wiping mechanism.
BACKGROUND OF THE INVENTION
Windshield wiping mechanism is generally used in vehicles to wipe the windshield glass to make it free from water, dirt and dust.
Conventional pantograph wiper mechanism comprises motor driven spindle, main arm, auxiliary arm parallel to main arm and a blade.
The drawback associated with said conventional pantograph windshield wiping mechanism is that, the windshield area below the main pantograph wiper arm is not cleaned which results in poor visibility and sometimes lead to accidents. Also, since the auxiliary arm is parallel to the main arm, it obstructs the vision.
Existing prior art describes the pantograph wiping mechanism in which an add-on blade is mounted beneath the main arm of the pantograph. The drawback associated with the said prior art is that, it requires the auxiliary arm parallel to the main arm which obstructs the vision. In addition to this, this also adversely affects aesthetic appeal. Again the pantograph is centrally fixed on the base of windshield, so the wiping is not that effective for the driver and possibility of accident increases.
OBJECTS OF INVENTION
The main object of this invention is to obviate the aforementioned drawbacks by providing an improved pantograph wiper mechanism, which cleans the maximum
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portion of the windshield glass, not affect the field of vision and contribute to good aesthetics value.
Yet another object of this invention is to provide an improved pantograph wiper mechanism which can reach to the desired close (parking) and open (up) positions.
STATEMENT OF INVENTION
An Improved pantograph wiper mechanism with auxiliary blade comprising:
a main arm having a hook portion, a body portion and a head portion coupled to a main blade at movable end and to a spindle at other end, said spindle is coupled to a ball pin located at said other end, said ball pin is movably fixed to an auxiliary arm coupled to an auxiliary blade such that said main arm and the auxiliary arm are coplanar.
The body portion and said hook portions are joined together through a connecting mechanism.
The head portion is provided with a provision to be held with said spindle, and is hinged to the said body portion.
One end of said auxiliary arm is connected to said ball-pin adjacent to the spindle and other end is connected to the said connecting mechanism.
Said spindle and said ball pin are fixed proximal to one end of the windshield depending on the driver's sitting position.
BRIEF DESCRIPTION OF DRAWINGS
Figure 1 shows assembly of the "Improved pantograph wiper mechanism with auxiliary blade" in accordance with this invention.
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Figure 2 shows the exploded view of the "Improved pantograph wiper mechanism with auxiliary blade".
Figure 3 shows vehicle assembly of the "Improved pantograph wiper mechanism with auxiliary blade".
DETAILED DESCRIPTION OF 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, improved pantograph wiper mechanism with auxiliary blade in accordance with this invention basically comprises of main arm (1), auxiliary arm (2), main blade (3), auxiliary blade (4) connecting means (5), spindle (6) and ball-pin (7). Said main arm (1) is having a head portion (la), a body portion (lb) and a hook portion (1c), said head portion (la) is connected to the spindle (6), and is hinged to the said body portion (lb). Said body portion (lb) and hook portions (lc) are linked together by a connecting means (5). One end (2a) of said auxiliary arm (2) is connected to the ball-pin (7) adjacent to the said spindle (6) and the other end (2b) is pivoted to the connecting means (5). Said main arm (1) is provided with coil spring (8) to apply pressure on said main blade (3), one end of said coil spring (8) is connected to the said head portion (la) and other end is connected to the said body portion (lb). Said auxiliary blade (4) is fastened to the said auxiliary arm (2) using two rivets (9).
During operation, the spindle (6) receives oscillatory motion from motor, said oscillatory motion is transferred to the said main wiper blade (3) through said main arm (1). Because of which the said main blade (3) moves between close (parking) position (A) and open position (B) on windshield (C). During movement of said main blade (3) from close (A) to open (B) positions and vice-versa, the said auxiliary blade (4) also moves over the windshield (C) thus cleaning an additional area (E) below the area (D) cleaned by said main blade (3).
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Advantages of the instant invention over the prior art are:
- More area is wiped by the main blade at the top and side portion.
- Use of auxiliary blade improves visibility at the bottom as well.
- Fixing the arrangement at one side increases the visibility for the driver.
- The placement of main arm and the auxiliary arm in same plane not only increases visibility but also increases the aesthetic value of the vehicle.
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.
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WE CLAIM
1. An Improved pantograph wiper mechanism with auxiliary blade
comprising:
a main arm having a hook portion, a body portion and a head portion coupled to a main blade at movable end and to a spindle at other end, said spindle is coupled to a ball pin located at said other end, said ball pin is movably fixed to an auxiliary arm coupled to an auxiliary blade such that said main arm and the auxiliary arm are coplanar.
2. The pantograph wiper mechanism as claimed in claim 1, wherein said body portion and said hook portions are joined together through a connecting mechanism.
3. The pantograph wiper mechanism as claimed in claim 1, wherein said head portion is provided with a provision to be held with said spindle, and is hinged to the said body portion.
4. The pantograph wiper mechanism as claimed in claim 1, wherein one end of said auxiliary arm is connected to said ball-pin adjacent to the spindle and other end is connected to the said connecting mechanism.
5. The pantograph wiper mechanism as claimed in claim 1, wherein said spindle and said ball pin are fixed proximal to one end of the windshield depending on the driver's sitting position.
6. The pantograph wiper mechanism as claimed in claim 1, wherein a spring is provided between said head portion and said body portion to facilitate pressure on said wiper blades.
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7. The pantograph wiper mechanism as claimed in claim 1. wherein a motor provides oscillatory motion to said spindle, said oscillatory motion is transferred to the said main blade through said main arm and said main blade and auxiliary blade moves between close (parking) and open positions.
8. An Improved pantograph wiper mechanism with auxiliary blade as herein described and illustrated in figures of the accompanying drawings.
Dated this 4th day of February 2009
TATA Motors Limited By their Agent & Attorney
(Karuna Goleria) of De PENNING & De PENNING
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