FORM 2
THE PATENT ACT 1970 (as amended)
[39 OF 1970]
&
The Patents Rules, 2003
COMPLETE SPECIFICATION
[See Section 10 and Rule 13]
TITLE: “A WIPER ARM MECHANISM FOR A WINDSHIELD OF A VEHICLE AND METHOD OF ASSEMBLING THEREOF”
Name of the Applicant: TATA MOTORS LIMITED
Address: Bombay House, 24 Homi Mody Street, Hutatma Chowk, Mumbai 400 001, Maharashtra, INDIA
Nationality: INDIAN
The following specification particularly describes the nature of the invention and the manner in which it is to be performed.

TECHNICAL FIELD
The disclosure relates to wiping mechanism used in vehicles, more particularly relates to string type wiping mechanism.
BACKGROUND AND PRIOR ART
Windshield wiping mechanism is generally used in vehicles to wipe the windshield glass to make it free from water, dirt and dust.
Conventional windshield wiper mechanism comprises of motor driven spindle, arm and blade. Wherein said arm is connected to the said spindle and blade, the rotary motion of the motor is converted to oscillatory motion of the blade through arm.
The drawback associated with said conventional windshield wiping mechanism is that, it is not possible to reach the desired parking and up positions with this type of mechanisms. Also the swept area is not maximum because the wiping blade does not reach desired parking and up position.
US2336007 teaches the wiping mechanisms used in air craft, comprises of motor driven spindle, arm, link structure and blade. Wherein said arm is connected to the said spindle and blade, the rotary motion of the motor is converted to oscillatory motion of the blade through arm. Said link structure assist in achieving the wiping. The drawback associated with said prior art is that, it requires additional link mechanism and the mounting of which obstructs the field of vision. In addition to this, this also affects aesthetic appeal.
In order to overcome the above said drawbacks, this invention is devised.
OBJECTIVES
The principal object is to provide an improved wiper arm mechanism which will not affect the field of vision and contribute for good aesthetics.
Another object is to provide a wiper mechanism which is flexible, non-elastic and capable of reaching desired parking and up positions of the windshield.

Yet another object is to provide an improved wiper arm mechanism which is simple in construction and cost effective.
SUMMARY OF THE DISCLOSURE
Accordingly, the present disclosure provides a wiper arm mechanism for a windshield of a vehicle, said wiper mechanism comprising a head portion (1a), a body portion (1b) and a hook portions (1c) connected together to configure an arm (1); a spindle (8) connected to the head portion (1a) of the arm (1) and mounted onto the windshield (C); a blade (7) connected to the hook portion (1c) of the arm (1); pair of strings (5, 6) connected to the spindle (8) and the hook portion (1c) of the arm (1), wherein said strings (5, 6) upon rotation of the arm (1) pulls the hook portion (1c) to facilitate the blade (7) for wiping the windshield (C) and a method of assembling wiper arm mechanism, said method comprises acts of connecting head portion (1a), body portion (1b) and hook portion (1c) together to configure an arm (1); connecting spindle (8) to the head portion (1a) of the arm (1) and mounting onto the windshield (C); connecting blade (7) to the hook portion (1c) of the arm (1); and fixing pair of strings (5, 6) to the spindle (8) and the hook portion (1c) of the arm (1).
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
The features of the present disclosure will become more fully apparent from the following description and appended claims, taken in conjunction with the accompanying drawings. Understanding that these drawings depict only several embodiments in accordance with the disclosure and are, therefore, not to be considered limiting of its scope, the disclosure will be described with additional specificity and detail through use of the accompanying drawings.
FIG. 1 shows line diagram of the wiper arm mechanism in side view in accordance with the
disclosure,
FIG. 2 shows line diagram of the wiper arm mechanism in top view in accordance with the
disclosure,
FIG. 3 shows exploded view of the wiper arm mechanism in accordance with the disclosure,
FIG. 4 shows side view articulation mechanism of the wiper arm in accordance with the
disclosure,

FIG. 5 shows connectivity in between the hook and blade in accordance with the disclosure,
and
FIG. 6 shows wiper arm mechanism fitted on a windshield of a vehicle in accordance with
the disclosure.
DETAILED DESCRIPTION
In the following detailed description, reference is made to the accompanying drawings, which form a part hereof. In the drawings, similar symbols typically identify similar components, unless context dictates otherwise. The illustrative embodiments described in the detailed description and drawings are not meant to be limiting. Other embodiments may be utilized, and other changes may be made, without departing from the spirit or scope of the subject matter presented herein. It will be readily understood that the aspects of the present disclosure, as generally described herein, and illustrated in the figures, can be arranged, substituted, combined, and designed in a wide variety of different configurations, all of which are explicitly contemplated and make part of this disclosure.
Referral Numerals:
1: Arm,
1a: Head portion of the arm (1),
1b: Body portion of the arm (1),
1c: Hook portion of the arm (1),
2: Provision for holding spindle,
3a: Slot on hook portion (1c) to fix string,
3b: Slot on hook portion (1c) to fix string,
4: Articulation means,
4a: Locking means,
5, 6: String,
7: Blade,
8: Spindle,
10: Provision on hook portion (1c) to hold the blade,
11: Coil spring,
12: Stopper,

13a, 13b: Periphery of the spindle (8), A: Parking position, B: Up position, C: Windshield, and α: Desired angle.
The present invention is in relation to a wiper arm mechanism for a windshield of a vehicle, said wiper mechanism comprising a head portion (1a), a body portion (1b) and a hook portions (1c) connected together to configure an arm (1); a spindle (8) connected to the head portion (1a) of the arm (1) and mounted onto the windshield (C); a blade (7) connected to the hook portion (1c) of the arm (1); pair of strings (5, 6) connected to the spindle (8) and the hook portion (1c) of the arm (1), wherein said strings (5, 6) upon rotation of the arm (1) pulls the hook portion (1c) to facilitate the blade (7) for wiping the windshield (C).
In one embodiment of the present disclosure the head portion (1a) is provided with a provision (2) to hold the spindle (8) and is hinged to the said body portion (1b).
In one embodiment of the present disclosure the body portion (1b) is provided with stopper (12) to prevent movement of the wiper blade (7) beyond desired wiping area.
In one embodiment of the present disclosure the hook portion (1c) is provided with slots (3a, 3b) to fix the strings (5, 6) and a provision (10) to hold the blade (7).
In one embodiment of the present disclosure the body portion (1b) is extruded at its one end to form an articulation means (4) for connecting with the hook portion (1c).
In one embodiment of the present disclosure the one end of said pair of strings (5, 6) is connected to the spindle (8) at its periphery (13a, 13b) and other end is fixed to in slot (3a, 3b) provided in base portion of the hook portion (1c) respectively and said strings (5, 6) are made to pass along the said body portion (1b) of the said arm (1).
In one embodiment of the present disclosure the said strings (5, 6) are made of metal which are flexible and non-elastic in nature.

In one embodiment of the present disclosure the said spindle (8) is rotated in oscillatory motion using a motor to oscillate the arm (1) between parking position (A) and up-position (B).
In one embodiment of the present disclosure the said string (5) facilitates pulling of the hook portion (1c) to tilt the blade (7) to an angle (α) to wipe the desired wiping area on the windshield (C) during rotation of the arm (1) from the parking position (A) to the up-position (B).
In one embodiment of the present disclosure the said string (6) facilitates pulling of the hook portion (1c) to pull the blade (7) from the up-position (B) to the parking position (A).
In one embodiment of the present disclosure the arm (1) is optionally provided with a coil spring (11), wherein one end of said coil spring (11) is connected to the head portion (1a) and other end is connected to the body portion (1b).
In one embodiment of the present disclosure the said coil spring (11) is pre-tensioned when the arm (1) moves from the parking position (A) to the up-position (B) and facilitates the arm (1) to move back from the up-position to the parking position (A).
The present disclosure is in relation to a method of assembling wiper arm mechanism, said method comprises acts of connecting head portion (1a), body portion (1b) and hook portion (1c) together to configure an arm (1); connecting spindle (8) to the head portion (1a) of the arm (1) and mounting onto the windshield (C); connecting blade (7) to the hook portion (1c) of the arm (1); and fixing pair of strings (5, 6) to the spindle (8) and the hook portion (1c) of the arm (1).
FIGS. 1 and 2 illustrate line diagrams of the wiper mechanism in side and top views in accordance with the disclosure. The wiper mechanism with double strings in accordance with the disclosure basically comprises of arm (1), first string (5), second string (6), spindle (8) and blade (7). The said arm (1) is having a head portion (1a), a body portion (1b) and a hook portion (1c), said head portion (1a) is provided with a provision (2) to hold in a spindle (8),

and is hinged to the said body portion (1b). One end of said arm (1) is connected to spindle (8) and hooked end (1c) is connected to said blade (7). One end of said first string (5) is connected to the said spindle (8) at its periphery (13a) and the other end is fixed in a slot (3a) provided in the base portion of said hook portion (1c) of said arm. One end of said second string (6) is connected to the said spindle (8) at its periphery (13b) and the other end is fixed in a slot (3b) provided in the base portion of said hook portion (1c) of said arm as shown in FIG 3. The said first string (5) is connected to the said spindle (8) at left side of the centre line of the arm when it is in up position based on the requirement of desired wiping area. The said second string (6) is connected to said spindle (8) at right side of the centre line of the arm when it is in parking position. The said hooking portion of said arm (1c) is provided with provision (10) to hold the said blade (7).
FIG. 3 illustrates exploded view of the wiper arm mechanism in accordance with the disclosure. The said body portion (1b) of said arm (1) is provided with stopper (12) to prevent the movement of the wiper blade beyond the desired wiping area. The head portion (1a) is provided with a provision (2) to hold the spindle (8). The said provision (2) is a hollow circular means in the head portion (1a) for holding the spindle (8) of the motor which is being passed. Thus the connectivity between the head portion (1a) of the arm (1) and the motor is made through the provision (2) for transfer of oscillatory motion from the motor to the arm (1) for wiping the windshield.
Optionally the said arm (1) is provided with a coil spring (11) to apply pressure on said blade (7). One end of the said coil spring (11) is connected to the said head portion (1a) and other end is connected to the said body portion (1b). During oscillatory movement the arm (1) moves from the parking position (A) to the up-position (B) which tensions the spring coil (11) during wiping. The spring (11) pulls back the wiper arm (1) after completing the wiping on the windshield (C) from the up-position (B) to the parking position (A). Thus the coil spring (11) retracts the wiper arm (1) to original parking position (A).
FIG. 4 illustrates side view of articulation mechanism. The body portion (1b) is extruded to form the articulation means (4) which is used to connect the hook portion (1c). The hook portion (1c) is inserted is provided with a provision to get connected with the articulation

means (4) so as to become a single unit after assembling. The articulation means (4) is provided with a locking means (4a) to connect the hook portion (1c) intact with the body portion (1b). The locking means (4a) is connected at the end portion of the articulation means (4) for locking the body portion (1b) with the hook portion (1c).
FIG. 5 illustrates connectivity in between the hook portion (1c) and the blade (7). The hook portion (1c) is provided with a provision (10) having hook of C-shaped for connecting with the blade (7). The said blade (7) is free to rotate in the wiping area.
FIG. 6 illustrates wiper arm mechanism fitted on a windshield of a vehicle in accordance with the disclosure. During operation the spindle (8) receives oscillatory motion from motor, said oscillatory motion is transferred to the said wiper blade (7) through said arm (1). Because of which the said blade (7) moves between parking position (A) and up position (B) on windshield (C). During movement of said blade (7) from parking to up positions, the said string (5) pulls the said hook portion (1c) of arm (1), which in turn tilts the said blade (7) by an angle (α) to the desired wiping area. During movement of said blade (7) from up position (B) to parking position (A) the said second string (6) pulls the said hook portion (1c) of arm (1), which in turn brings the said blade (7) to original parking position (A).
Advantages:
The present disclosure provides for a wiper arm mechanism with double strings, which will
not affect the field of vision and contribute for good aesthetics.
The present disclosure provides for a wiper arm mechanism which is flexible, and which can reach to the desired parking (close) and open positions.
The present disclosure provides for a wiper arm mechanism which is simple in construction and cost effective.
Equivalents:
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 wiper arm mechanism for a windshield of a vehicle, said wiper mechanism comprising:
a head portion (1a), a body portion (1b) and a hook portions (1c) connected together to configure an arm (1);
a spindle (8) connected to the head portion (1a) of the arm (1) and mounted onto the windshield (C);
a blade (7) connected to the hook portion (1c) of the arm (1);
pair of strings (5, 6) connected to the spindle (8) and the hook portion (1c) of the arm (1), wherein said strings (5, 6) upon rotation of the arm (1) pulls the hook portion (1c) to facilitate the blade (7) for wiping the windshield (C).
2. The wiper arm mechanism as claimed in claim 1, wherein the head portion (1a) is provided with a provision (2) to hold the spindle (8) and is hinged to the said body portion (1b).
3. The wiper arm mechanism as claimed in claim 1, wherein the body portion (1b) is provided with stopper (12) to prevent movement of the wiper blade (7) beyond desired wiping area.
4. The wiper arm mechanism as claimed in claim 1, wherein the hook portion (1c) is provided with slots (3a, 3b) to fix the strings (5, 6) and a provision (10) to hold the blade (7).
5. The wiper arm mechanism as claimed in claim 1, wherein the body portion (1b) is extruded at its one end to form an articulation means (4) for connecting with the hook portion (1c).
6. The wiper arm mechanism as claimed in claim 1, wherein one end of said pair of strings (5, 6) is connected to the spindle (8) at its periphery (13a, 13b) and other end is fixed to in slot (3a, 3b) provided in base portion of the hook portion (1c) respectively and said strings (5, 6) are made to pass along the said body portion (1b) of the said arm (1).

7. The wiper arm mechanism as claimed in claim 1, wherein said strings (5, 6) are made of metal which are flexible and non-elastic in nature.
8. The wiper arm mechanism as claimed in claim 1, wherein said spindle (8) is rotated in oscillatory motion using a motor to oscillate the arm (1) between parking position (A) and up-position (B).
9. The wiper arm mechanism as claimed in claim 7, wherein said string (5) facilitates pulling of the hook portion (1c) to tilt the blade (7) to an angle (α) to wipe the desired wiping area on the windshield (C) during rotation of the arm (1) from the parking position (A) to the up-position (B).
10. The wiper arm mechanism as claimed in claims 7 and 8, wherein said string (6) facilitates pulling of the hook portion (1c) to pull the blade (7) from the up-position (B) to the parking position (A).
11. The wiper arm mechanism as claimed in claim 1, wherein the arm (1) is optionally provided with a coil spring (11), wherein one end of said coil spring (11) is connected to the head portion (1a) and other end is connected to the body portion (1b).
12. The wiper arm mechanism as claimed in claim 11, wherein said coil spring (11) is pre-tensioned when the arm (1) moves from the parking position (A) to the up-position (B) and facilitates the arm (1) to move back from the up-position to the parking position (A).
13. A method of assembling wiper arm mechanism, said method comprises acts of:
connecting head portion (1a), body portion (1b) and hook portion (1c) together to configure an arm (1);
connecting spindle (8) to the head portion (1a) of the arm (1) and mounting onto the windshield (C);
connecting blade (7) to the hook portion (1c) of the arm (1); and
fixing pair of strings (5, 6) to the spindle (8) and the hook portion (1c) of the arm (1).

14. A wiper arm mechanism for a windshield of a vehicle and a method of assembling the wiper arm mechanism are substantially as herein above described and as illustrated in accompanying drawings.