FORM 2
The Patent Act 1970
(39 OF 1970)
AND
THE PATENT RULES, 2005
COMPLETE SPECIFICATION (SEE SECTION 10; RULE 13)
TITLE OF THE INVENTION
“DUAL LOCKING MECHANISM FOR INTERIOR TRIM ASSEMBLY”
APPLICANT (S)
TATA MOTORS LIMITED
an Indian Company
Bombay House, 24 Homi Mody Street,
Hutatma Chowk, Mumbai - 400 001,
Maharashtra, India.
PREAMBLE TO THE DESCRIPTION
The following specification particularly describes and ascertains the nature of this invention and the manner in which it is to be performed:-

FIELD OF THE INVENTION
[0001] The present disclosure relates to interior trim assembly, and more particularly relates to a dual locking mechanism for interior trim assembly which ensures preload condition and robust mounting scheme for two mating trim members.
BACKGROUND OF THE INVENTION
[0002] The sound inside a vehicle cabin is composed of many elements such as engine noise, wind cutting noise, trim noises, seat noises, tire noise, etc. The fundamental elements of which are irritating noises comprising of Buzz, Squeaks and Rattles (BSR). Rattling noises from interior trims are one of the major concerns of customer irritant noises. Customers increasingly perceive BSR noises as direct indicators of vehicle build quality and durability. The high profile nature of S&R has led manufacturer to formulate numerous specifications for assemblies and components. BSR issues arising from doors are of high importance and require greater attention for resolving the same. The rattling noises from door trims and Rear Quarter Trims are one of the major concerns of customer irritant noises. There are many triggers for this rattling noise, which are improper snapping, insufficient preload, ribs not provided, insufficient mounting scheme and looseness in trim welded parts etc. Under the different road condition, noise from interior trims are more irritating to customer as these are nearer to customer. Different types of noise from interior trims joinery is due to insufficient fixing and material pairing. The rattling and squeaking noise from the interior trim joinery is perianal issue in almost all the project. The major contribution for this noise was insufficient/weak mounting scheme. In traditional approach, felt is provided between the joinery of two trims to avoid the rubbing effect.

[0003] Conventional configuration of the automobile door trim (10) is described with reference to FIGS. 1a-1c. Two interior trim members (11 and 12) are joined by metal clip (13), flower button or vibration welding as shown in the FIG. 1c. The joinery of the trim members (11 and 12) are illustrated in the FIG. 1b. Felt is provided between joinery to avoid the rubbing effect. Conventional approach for Joining of two interior trims (11 and 12) are by using metal clip, flower button or vibration welding as shown in FIG. 1c. This trim fixing create the looseness in two trim parts joinery over the period of time. Due to no preload condition and guiding locator not available in the trim joinery area. In addition, the trim joinery not easy to fix on panel and loose fitment of these create BSR issues.
OBJECT OF THE INVENTION
[0004] The principal object of the embodiments herein is to provide a dual locking mechanism for interior trim assembly which ensures preload condition and robust mounting scheme for two mating trim members.
[0005] Another object of the embodiments herein is to provide combined effect to restrict the movement of trim joinery which results in eliminating rattle and squeak noise issue.
SUMMARY OF THE INVENTION
[0006] In one aspect object is satisfied by providing an interior trim assembly of an automobile. The interior trim assembly comprising a first trim member, a second trim member and a rib-lock clip. The first trim member comprising guiding lug and auxiliary rib protruding from one end of the first trim member. The second trim member comprising holes at one end to insert the guiding lug and the auxiliary rib of the first trim member. The rib-lock clip to

lock the auxiliary rib. When the first trim member is mated with the second trim member, the first trim member is locked with the second trim member at a first position (27) using the guiding lug and at a second position (28) using the rib-lock clip.
[0007] In an embodiment, the first trim member and the second trim member is associated with a door body of the automobile.
[0008] In an embodiment, the first trim member and the second trim member locked at the first position (27) and the second position (28) eliminates looseness & clearance issue.
[0009] In an embodiment, the first trim member (21) and the second trim member (24) locked at the first position (27) and the second position (28) eliminates rattle and squeak noise issue.
[0010] These and other aspects of the embodiments herein will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that the following descriptions, while indicating preferred embodiments and numerous specific details thereof, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the embodiments herein without departing from the spirit thereof, and the embodiments herein include all such modifications.
BRIEF DESCRIPTION OF DRAWINGS
[0011] This connector is illustrated in the accompanying drawings, throughout which like reference letters indicate corresponding parts in the

various figures. The embodiments herein will be better understood from the following description with reference to the drawings, in which:
[0012] FIGS. 1a-1c illustrates single locking mechanism for interior trim assembly, according to prior art; and
[0013] FIGS. 2a-2c illustrates dual locking mechanism for interior trim assembly, according to embodiments as disclosed herein.
DETAILED DESCRIPTION OF THE INVENTION
[0014] The embodiments herein and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments that are illustrated in the accompanying drawings and detailed in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. Also, the various embodiments described herein are not necessarily mutually exclusive, as some embodiments can be combined with one or more other embodiments to form new embodiments. The term “or” as used herein, refers to a non-exclusive or, unless otherwise indicated. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein can be practiced and to further enable those skilled in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
[0015] The accompanying drawings are used to help easily understand various technical features and it should be understood that the embodiments presented herein are not limited by the accompanying drawings. As such, the present disclosure should be construed to extend to any alterations, equivalents and substitutes in addition to those which are particularly set out in the accompanying drawings. Although the terms first, second, etc. may be used

herein to describe various elements, these elements should not be limited by these terms. These terms are generally only used to distinguish one element from another.
[0016] Referring now to the drawings, and more particularly to FIGS. 2a-2c, there are shown preferred embodiments.
[0017] FIGS. 2a-2c illustrates dual locking mechanism for an interior trim assembly (20) of an automobile, according to embodiments as disclosed herein. The interior trim assembly (20) comprising a first trim member (21), a second trim member (24) and a rib-lock clip (26). The first trim member (21) and the second trim member (24) is associated with a door body of the automobile. The first trim member (21) comprising guiding lug (22) and auxiliary rib (23) protruding from one end of the first trim member (21). The second trim member (24) comprising holes (25) at one end to insert the guiding lug (22) and the auxiliary rib (23) of the first trim member (21). The rib-lock clip (26) to lock the auxiliary rib (23). When the first trim member (21) is mated with the second trim member (24), the first trim member (21) is locked with the second trim member (24) at a first position (27) using the guiding lug (22) and at a second position (28) using the rib-lock clip (26). The first trim member (21) and the second trim member (24) locked at the first position (27) and the second position (28) eliminates looseness & clearance issue. The first trim member (21) and the second trim member (24) locked at the first position (27) and the second position (28) eliminates rattle and squeak noise issue.
[0018] Unlike the conventional interior trim assembly, the proposed fixing features has dual locking mechanism which ensures preload condition and robust mounting scheme for two mating trim parts. The dual locking mechanism provides a combined effect to restrict the movement of trim assembly. The

proposed dual locking mechanism ensures the looseness & clearance issue which results in eliminating rattle and squeak noise issue. Also use of additional cost of using the BSR felt is elimination as no felt is used in the proposed interior trim assembly. The dual locking mechanism of the interior trim assembly eliminates the irritant noise from interior trims, the fitment and assembly issues for inner trims. It further reduces the cost by eliminating felt and foam pieces at joinery and a risk of Squeak and rattling noise due to earlier used mounting scheme used for door trims with maintaining requirement of Gap and flush.
[0019] The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.

We Claim:
1. An interior trim assembly (20) of an automobile, comprising:
a first trim member (21) comprising guiding lug (22) and auxiliary rib (23) protruding from one end of the first trim member (21);
a second trim member (24) comprising holes / slots (25) at one end to insert the guiding lug (22) and the auxiliary rib (23) of the first trim member (21); and
a rib-lock clip (26) to lock the auxiliary rib (23),
wherein when the first trim member (21) is mated with the second trim member (24), the first trim member (21) is locked with the second trim member (24) at a first position (27) using the guiding lug (22) and at a second position (28) using the rib-lock clip (26).
2. The interior trim assembly (20) as claimed in claim 1, wherein the first trim member (21) and the second trim member (24) is associated with a door body of the automobile.
3. The interior trim assembly (20) as claimed in claim 1, wherein the first trim member (21) and the second trim member (24) locked at the first position (27) and the second position (28) eliminates looseness & clearance issue.
4. The interior trim assembly (20) as claimed in claim 1, wherein the first trim member (21) and the second trim member (24) locked at the first position (27) and the second position (28) eliminates rattle and squeak noise issue.