The present disclosure generally relates to back door of a vehicle. The present invention, in particular, relates to a reinforcement bracket in the back door of the vehicle for damping low frequency noise.
BACKGROUND
[0002] In a vehicle, a back door is provided to access the cargo compartment of a vehicle from the outside. The structure of back door includes an outer panel and an inner panel. When the vehicle is in motion and the back door is in locked state, a noise is felt by the occupants inside the vehicle cabin.
[0003] When the vehicle is in motion, vibrations of engine (hereinafter referred as engine vibrations) is transmitted to vehicle body. In a particular case, when the vehicle is running in low speed, the engine vibrations are transmitted to the vehicle body. The panels of the back door that is in contact with inside cabin air resonates with the engine vibrations. This resonating phenomenon results in low frequency booming noise. This low frequency booming noise provides discomfort to the passengers while travelling thus deteriorates vehicle's NVH performance.
[0004] Referring to FIG. 1 illustrating a bracket to reduce low frequency vibrations in back door 100 of a vehicle in accordance with the existing art. In the back door 100 of a vehicle, a gap is formed between the inner panel 101 and the outer panel 102. To reduce the vibrations in the back door 100, a bracket 103 is installed in the gap, as a reinforcement, to provide rigidity in the gap region. The bracket 103 comprises a base portion 103a and a plurality of annex portions 103b, 103c (top annex portion 103b and bottom annex portion 103c) integrally originating from the top and bottom end of the base portion 103a. The top annex portion 103b of the bracket 103 is securely attached on the outer panel 102 of the back door 100 using a sealer. The bottom annex portion 103c of the bracket 103 is

welded on the inner panel 101 of the back door 100. In the installed state, the bracket 103 enhances rigidity in the gap region of the inner panel 101 and the outer panel 102 of the back door 100. Generally, the bracket 103 is manufactured with sheet metal. This limits the ability of the bracket 103 to be used in different types of vehicle in order to reduce vibrations in the back door 100 of a vehicle. Therefore, there is scope of making further modification on the bracket structure. In existing design, a separate mass damper is used to damp the vibration or noise. However, this adds an additional part in the vehicle which increases weight and cost of the vehicle.
[0005] Accordingly, there is a need for a common reinforcement bracket for damping low frequency noise in back door of different types of vehicle.
SUMMARY
[0006] This summary is provided to introduce concepts related to a reinforcement bracket. The concepts are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.
[0007] The present subject matter relates to a reinforcement bracket for damping low frequency noise in back door of a vehicle. The reinforcement bracket comprises a hat-shaped frame and a support rod. The hat-shaped frame has an elevated portion and a plurality of base portions each integrally originating from ends of the elevated portion. The support rod has a base member fixedly attached to the elevated portion of the hat shaped frame, a first member integrally extending angularly from first end of the base portion and a second member integrally extending angularly from the second end of the base portion. The hat-shaped frame is securely attached to outer panel of the back door through the plurality of base portions. The support rod is securely attached to inner panel of the back door through the second member of the support rod.

[0008] In an aspect, a longitudinal bead is provided in the elevated portion of the hat-shaped frame to accommodate base member of the support rod.
[0009] In an aspect, the base member of the support rod is welded on the longitudinal bead provided on the elevated portion of the hat-shaped frame.
[0010] In an aspect, the plurality of base portions of the hat-shaped frame is attached to the outer panel of the back door using a sealer.
[0011] In an aspect, the second member of the support rod is welded on the inner panel of the back door to securely attach the support rod on the inner panel of the back door.
[0012] In an aspect, the first member of the support rod has threaded profile to accommodate a detachable mass damper.
[0013] In an aspect, the detachable mass damper varies in the weight and the weight of the detachable damper depends on the requirement of damping in back door of a vehicle.
[0014] To further understand the characteristics and technical contents of the present subject matter, a description relating thereto will be made with reference to the accompanying drawings. However, the drawings are illustrative only but not used to limit the scope of the present subject matter.
[0015] Various objects, features, aspects, and advantages of the inventive subject matter will become more apparent from the following detailed description of preferred embodiments, along with the accompanying drawing figures in which like numerals represent like components.
BRIEF DESCRIPTION OF FIGURES
[0016] The illustrated embodiments of the present disclosure will be best understood by reference to the drawings, wherein like parts are designated by like numerals throughout. The following description is intended only by way of example, and simply illustrates certain selected embodiments of devices, systems,

and processes that are consistent with the subject matter as claimed herein, wherein:
[0017] FIG. 1 illustrates a bracket to reduce low frequency vibrations in back door of a vehicle in accordance with the existing art;
[0018] FIG. 2 illustrates isometric view of an exemplary reinforcement bracket that can be utilized to implement one or more exemplary embodiments of the present disclosure;
[0019] FIG. 3 illustrates the reinforcement bracket in installed state that can be utilized to implement one or more exemplary embodiments of the present disclosure; and
[0020] FIG. 4 illustrates performance graphs before and after implementation of the proposed reinforcement bracket in the back door of a vehicle.
[0021] The figures depict embodiments of the present subject matter for the purposes of illustration only. A person skilled in the art will easily recognize from the following description that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the disclosure described herein.
DETAILED DESCRIPTION
[0022] A few aspects of the present disclosure are explained in detail below with reference to the various figures. Example implementations are described to illustrate the disclosed subject matter, not to limit its scope, which is defined by the claims. Those of ordinary skill in the art will recognize a number of equivalent variations of the various features provided in the description that follows.
Definitions
[0023] In the disclosure hereinafter, one or more terms are used to describe various aspects of the present disclosure. For a better understanding of the present

disclosure, a few definitions are provided herein for better understating of the present disclosure.
[0024] "Engine vibrations" may be defined as vibrations generated by the engine and transmitted towards the back door of a vehicle.
EXEMPLARY IMPLEMENT A TIONS
[0025] While the present disclosure may be embodied in various forms, there are shown in the drawings, and will hereinafter be described, some exemplary and non-limiting embodiments, with the understanding that the present disclosure is to be considered an exemplification of the invention and is not intended to limit the invention to the specific embodiments illustrated. Not all of the depicted components described in this disclosure may be required, however, and some implementations may include additional, different, or fewer components from those expressly described in this disclosure. Variations in the arrangement and type of the components may be made without departing from the scope of the claims as set forth herein.
[0026] During low speed running of a vehicle, a low frequency booming noise is generated in the back door. In the automobile industry, noise, vibration and harshness are quantitative parameters to determine the NVH performance of the vehicle. The low frequency booming noise in the back door of a vehicle deteriorate the NVH performance. The low frequency booming noise reduces the sound quality in the car and negatively affect the psychology and physiology of passengers.
[0027] To solve the problem, a reinforcement bracket for damping low frequency noise in back door of all types of vehicles, is required.
[0028] In order to achieve this goal of damping low frequency noise in back door of a vehicle, a reinforcement bracket may be utilized. The reinforcement bracket is described in more detail below.

[0029] FIG. 2 illustrates isometric view of an exemplary reinforcement bracket that can be utilized to implement one or more exemplary embodiments of the present disclosure. The reinforcement bracket 200 comprises a hat-shaped frame 201 and a support rod 202 fixedly attached with the hat-shaped frame 201. The hat-shaped frame 201 has an elevated portion 201a and a plurality of base portions 201b. The plurality of base portions 201b integrally originates from opposite ends of the elevated portion 201a such that the plurality of base portions 201b and the elevated portion 201a creates a hat-shaped profile of the frame 201. A longitudinal bead 203 is provided in the elevated portion 201a of the hat-shaped frame 201. In an aspect, the longitudinal bead 203 is provided in the middle along the length of the elevated portion 201a. The support rod 202 of the reinforcement bracket 200 is arc welded to the elevated portion 201a of the hat-shaped frame 201 at the longitudinal bead 203.
[0030] The support rod 202 has a base member 202a, a first member 202b
and a second member 202c. The base member 202a of the support rod 202 has a straight profile having a first end and a second end. The first member 202b of the support rod 202 integrally extends angularly from the first end of the base member 202a. In an aspect, the first member 202b extends perpendicularly from the first end of the base member 202a. Based on the vehicle design and NVH requirement, provision is provided on the first member 202b to accommodate a detachable mass damper 205. In an aspect, a threaded profile is provided at the free end of the first member 202b to accommodate the detachable mass damper 205. Further, the weight of the detachable mass damper 205 can be varied as per the amount of damping required in back door of a vehicle.
[0031] The second member 202c of the support rod 202 integrally extends angularly from the second end of the base member 202a. In an aspect, the second member 202c extends perpendicularly from the second end of the base member 202a.
[0032] In an aspect, the second member 202c of the support rod 202 comprises an L-shaped portion 202ca and an extension portion 202cb. The

extension portion 202cb integrally connects the second end of the base member 202a of the support rod 202 with the L-shaped portion 202ca of the second member 202c. The L-shaped portion 202ca of the second member 202c is arc welded on the inner panel of the back door.
[0033] FIG. 3 illustrates the reinforcement bracket in installed state that can be utilized to implement one or more exemplary embodiments of the present disclosure. The hat-shaped frame 201 is securely attached to the outer panel 301 of the back door 300. The plurality of base portions 201b of the hat-shaped frame 201 is securely attached to the outer panel 301, in a way, that a gap is maintained between the elevated portion 201a of the hat-shaped frame 201 and the outer panel 301 of the back door 300. In an aspect, the plurality of base portions 201b of the hat-shaped frame 201 are securely attached to the outer panel 301 of the back door 300 using a sealer.
[0034] The support rod 202 is securely attached to the inner panel 302 of the back door 300. The second member 202c of the support rod 202 is securely attached to the inner panel 302, in a way, that the support rod 202 together with the hat-shaped frame 201 secure a connection between the inner panel 302 and the outer panel 301 of the back door 300 resulting in providing rigidity in the structure of the back door 300. In an aspect, the second member 202c of the support rod 202 is welded on the inner panel 302 of the back door 300 to securely attach the support rod 202 on the inner panel 302 of the back door 300.
[0035] In an aspect, The L-shaped portion 202ca of the second member 202c is securely attached to the inner panel 302 of the back door 300 in a way that the L-shaped portion 202ca of the second member 202c completely rest on the inner panel 302.
WORKING OF THE REINFORCEMENT BRACKET IN INSTALLED STATE
[0036] The structure of the reinforcement bracket 200 is designed such that the hat-shaped frame 201 and the support rod 202 are fixedly attached to each

other and together the hat-shaped frame 201 and the support rod 202 creates a connection between the inner panel 301 and the outer panel 302 of the back door. The formation of this connection between the inner panel 302 and the outer panel 301 provides rigidity in the back door 300 structure and facilitate in damping of the low frequency noise created in the back door 300. In addition, the reinforcement bracket 200 is equipped with the provision of providing a detachable mass damper 205 to further improve damping of low frequency noise for better comfort of the passenger. The mass damper 205 can be removed from the support rod 202 if needed and can also be replaced with another mass damper with different weight based on the amount of damping required in the vehicle.
[0037] FIG. 4 illustrates performance graphs before and after implementation of the proposed reinforcement bracket in the back door of a vehicle. The black line in the graph indicates low frequency noise generated in the back door of a vehicle without implementation of the reinforcement bracket 200 and the red dotted line indicates low frequency noise generated in the back door 300 of a vehicle after implementation of the reinforcement bracket 200. The graph clearly shows the damping of low frequency noise achieved after implementing the proposed reinforcement bracket 200. In an aspect, improvement of about 3 dB is achieved by implementing the proposed reinforcement bracket 200 in the back door of the vehicle.
ADVANTAGES
[0038] The reinforcement bracket ensures damping of low frequency noise in back door of different types of vehicles. Further, the proposed reinforcement bracket works both as a reinforcement bracket as well as a damper.
[0039] In addition to above mentioned advantages, the proposed reinforcement bracket is capable of improving the NVH performance of the vehicle.

[0040] The above description does not provide specific details of the manufacture or design of the various components. Those of skill in the art are familiar with such details, and unless departures from those techniques are set out, techniques, known, related art or later developed designs and materials should be employed. Those in the art are capable of choosing suitable manufacturing and design details.
[0041] Further, the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. It will be appreciated that several of the above-disclosed and other features and functions, or alternatives thereof, may be combined into other systems or applications. Various presently unforeseen or unanticipated alternatives, modifications, variations, or improvements therein may subsequently be made by those skilled in the art without departing from the scope of the present disclosure as encompassed by the following claims.
[0042] The claims, as originally presented and as they may be amended, encompass variations, alternatives, modifications, improvements, equivalents, and substantial equivalents of the embodiments and teachings disclosed herein, including those that are presently unforeseen or unappreciated, and that, for example, may arise from applicants/patentees and others.
[0043] It will be appreciated that variants of the above-disclosed and other features and functions, or alternatives thereof, may be combined into many other different systems or applications. Various presently unforeseen or unanticipated alternatives, modifications, variations, or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the following claims.

We Claim:

1. A reinforcement bracket (200) for a back door (300) of a vehicle, the
reinforcement bracket (200) comprises:
a hat-shaped frame (201) having an elevated portion (201a) and plurality of base portions (201b) each integrally originating from ends of the elevated portion (201a); and
a support rod (202) having a base member (202a) fixedly attached to the elevated portion (201a) of the hat shaped frame (201), a first member (202b) integrally extending angularly from first end of the base portion (202a) and a second member (202c) integrally extending angularly from the second end of the base portion (202a), wherein
the hat-shaped frame (201) is securely attached to outer panel (301) of the back door (300) through the plurality of base portions (201b); and
the support rod (202) is securely attached to inner panel (302) of the back door (300) through the second member (202c) of the support rod (202).
2. The reinforcement bracket (200) as claimed in claim 1, wherein a
longitudinal bead (203) is provided in the elevated portion (201a) of the hat-
shaped frame (201) to accommodate base member (202a) of the support rod (202).
3. The reinforcement bracket (200) as claimed in claim 2, wherein the base member (202a) of the support rod (202) is welded on the longitudinal bead (203) provided on the elevated portion (201a) of the hat-shaped frame (201).
4. The reinforcement bracket (200) as claimed in claim 1, wherein the plurality of base portions (201b) of the hat-shaped frame (201) are attached to the outer panel (301) of the back door using a sealer.

5. The reinforcement bracket (200) as claimed in claim 1, wherein the second
member (202c) of the support rod (202) is welded on the inner panel (302) of the
back door (300) to securely attach the support rod (202) on the inner panel (302)
of the back door (300).
6. The reinforcement bracket (200) as claimed in claim 1, wherein the first
member (202b) of the support rod (202) has threaded profile to accommodate a
detachable mass damper (205).
7. The reinforcement bracket (200) as claimed in claim 6, wherein weight of the detachable mass damper (205) is varied as per the amount of damping required in back door of a vehicle.
8. The reinforcement bracket (200) as claimed in claim 1, wherein the second member (202c) of the support rod (202) comprises an L-shaped portion (202ca) and an extension portion (202cb).
9. The reinforcement bracket (200) as claimed in claim 8, wherein the extension portion (202cb) integrally connects the second end of the base member (202a) of the support rod (202) with the L-shaped portion (202ca) of the second member (202c).