FORM 2
THE PATENTS ACT 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
PROVISIONAL SPECIFICATION
(See Section 10; rule 13)
TITLE OF THE INVENTION DOOR HINGE WITH INTEGRAL DOOR CHECK


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

INVENTORS
Mr.Manoj Gupta &Mr. Abhay Dandekar both 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:
The present invention relates to the hinges and door checks used in automobiles door systems.
BACKGROUND OF INVENTION:
A conventional door check functions to stop the door at in between positions as well as at end position i.e. at full open condition. Door check in modern days comprises of a strip of metal or plastic with indentations. This strip moves in a case as door is opened or closed. The case comprises of rollers and rubber springs which make sure that roller always contact the strip. When roller is in between two indentations it results in door stop.
OBJECTS OF INVENTION:
> The main object of this invention is to integrate the door check function in door hinge.
> Yet another object of this invention is to provide cost effective alternative to conventional check strap.
> Yet another object of this invention is to avoid door check projection in the door cavity and thus improve the door packaging.
BRIEF DESCRIPTION OF INVENTION:
Door hinge with Integral door check for and automobile door in accordance with this invention basically comprises of Door hinge assembly, Two spacers with indentations, rubber bush/ spring and spacer supports. Door spacers have indentations in circular pattern. These spacers are mounted on hinge facing the indentations towards each other and also concentric to the hinge axis. The spacers are connected to body side bracket and door side bracket of the hinge through spacer supports. Rubber bush is assembled behind the inner spacer which exerts force on the spacers to remain in contact with each other. As the door moves, because of relative motion between
3 1 MAR 2009

door side bracket and body side bracket of the hinge, it results in relative motion between two spacers. As they override the indentations it gives the door stop feel in between and also at the end serving the purpose of door check.
BRIEF DESCRIPTION OF THE DRAWINGS
In accordance to the present invention
Fig 1 shows view of door hinge assembly
Fig2 shows exploded view of door hinge assembly.
Fig3 shows door hinge assembly without door check function.
Fig 4 and Fig 5 shows assembly procedure of spacers with hinge.
Fig5 shows alternate proposal to achieve spring action on spacers.
DETAILED DESCRIPTION OF INVENTION:
Referring now to the views showings the areas, only for the purpose of illustrating the
invention, and not for the purpose of limiting the same.
Refereeing figs 1 to 6
Fig. 1 Shows the assembled view of the door hinge assembly. Fig 2 explains this
hinge design through exploded view. Said hinge assembly comprises a hinge leaf
body side (1), hinge leaf door side (2), Upper spacer (3), Lower spacer (4), metal
embedded rubber bush (5), Upper spacer sleeve (6), Lower spacer sleeve (7).
Fig 3 explains the basic hinge assembly, which is formed by said hinge leaf body side (1) and Hinge leaf door side (2) assembled through two pins.
Fig 4 explains in process assembly of door check spacers on hinge. The assembly (8) of lower spacer (4) and sleeve (7)is assembled on said hinge, with reference of hinge pin and Hinge leaf door side (2). Above this assembly (8), an assembly (9) of the upper spacer (3)and sleeve (6) is assembled on hinge, with reference of hinge pin, assembly (8) of lower spacer (4) and sleeve (7) and hinge leaf body side (1).
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Rubber bush (5) is inserted between upper spacer and Hinge leaf body side which ensures the engagement and stacking of the child parts.
Fig 4 also shows the relation between assembly (9) of upper spacer (3) and sleeve (6) and assembly (8) of lower spacer (4) and sleeve(7). Upper spacer (3) consists of at least two serrated portions or peaks (1 Oa, 1 Ob) and lower spacer (4) consists of at least one serrated portion or peak (11), said peaks being radially placed about the hinge axis of the hinge.
When door is set to open, the assembly (8)of lower spacer (4) and sleeve (7) tries to move with hinge leaf door side (2). As the peak (11) of said lower spacer (4) approaches the mating peak (10a, 10b) on upper spacer (3) it tries to lift the assembly (9) of upper spacer (3) and sleeve (6). The rubber bush (5) provided above the upper spacer (3), acts as a spring and constantly gives reaction on the upper spacer and sleeve assembly (9) resulting in resistance to the door movement. This resistance is maximum at the point when the peak (11) of said lower spacer (4) coincides with the peak (10a, 10b) of said upper spacer (3). The resistance starts dropping when the peaks (10a, 10b & 11) cross each other and the resistance is nil when said peak (11) of said lower spacer (4) matches the crest (12) formed between said two peaks (10a, 10b) of said upper spacer (3). At this position the door movement is stopped/checked. This phenomenon can be seen when peak (11) on lower spacer (4) approaches second peak (10b) on upper spacer (3). After passing over second peak (10b) said door is in the full open condition and remains in such position.
While closing the door it goes through the same cycle but in reverse order to have door check performance.
Fig 5 shows the assembly with compression spring which can be an alternative to rubber spacer.
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The upper spacer and lower spacer can be manufactured in plastic material to avoid separate sleeves which assist in eliminating noise at the time of each engagement.
Advantages:
1) Much more cost effective than any other conventional methods.
2) Number of Parts required are less compared to conventional vehicles
3) Very Easy to Assemble and dismantle and hence easily serviceable.
4) Cycle Time required for assembly is less.
5) No reinforcements on door as well as body for mounting door check.
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.
Dated this 31st day of March 2009
TATA MOTORS LIMITED By their Agent & Attorney

Karuna Goleria of DePENNING & DePENNING