Description:TECHNICAL FIELD
[0001] The present subject matter relates generally to a drum brake assembly and specifically, to a rubber boot that accommodates a hand brake lever within the drum brake assembly.
BACKGROUND
[0002] Generally, a vehicle comprises of a frame extending rearwardly from a front portion of the vehicle. A vehicle, generally a two wheeled vehicle or a three wheeled vehicle is equipped with drum brakes. Drum brakes are a brake system with brake drums (rotor) which rotate with the wheels. Inside each drum are brake shoes fitted with brake linings (friction material). With this system, friction is generated by pressing the brake linings against the inside surfaces of the drums. This friction converts kinetic energy into thermal energy. Drum rotation helps to press the shoes and the lining against the drum with more force, offering superior braking force in comparison with disc brakes.
[0003] Conventionally, drum brakes are provided with a hand brake lever to enable manual engagement of the brake when the vehicle is in parked condition. In the existing brake assembly for three wheeled vehicles, the back plate assembly has a slot in the main plate to allow parking lever movement. Through this slot dust / mud entry is observed into the drum brake assembly in field. Due to entry of mud, it can lead to problems such as reduction of braking efficiency, increased abrasions, reduction of brake shoe life, unexplained noise problems during braking.
[0004] Therefore, it is necessary to provide a solution that enables convenient operation of the parking brake lever while ensuring prevention of entry of foreign items within the slot for accommodating the parking lever.
[0005] Further limitations and disadvantages of conventional and traditional approaches will become apparent to one of skill in the art, through comparison of described systems with some aspects of the present disclosure, as set forth in the remainder of the present application and with reference to the drawings.
SUMMARY
[0006] Aspects of the present disclosure pertain to a rubber boot that accommodates a hand brake lever within the drum brake assembly.
[0007] The present disclosure pertains to a drum brake assembly having a rubber boot. The drum brake assembly comprises a pair of brake shoes, the pair of brake shoes is operable by a brake cam lever. A face cam is disposed such that it transfers rotary actuating force from the brake cam lever to the pair of brake shoes. A rubber boot is disposed on a back plate of an auto adjuster such that a parking lever is accommodated within the rubber boot. The rubber boot has a pre-defined elastic modulus and enables a dust and waterproof seal around the parking lever ensuring prevention of entry of dust particles into a parking lever slot.
[0008] An aspect of the present disclosure pertains to a drum brake assembly. The drum brake assembly comprises a pair of brake shoes such that the pair of brake shoes are operable by a brake cam lever. A face cam is provided that is configured to transfer rotary actuating force from the brake cam lever to the pair of brake shoes. A parking lever is accommodated within a rubber boot, wherein the rubber boot has a pre-defined elastic modulus.
[0009] In an embodiment, the brake drum assembly comprises an auto-adjuster.
[00010] In an embodiment, the rubber boot is configured with a plurality of bellows disposed along the length of the rubber boot.
[00011] In an embodiment, the rubber boot is disposed at an angle relative to a horizontal axis of the parking lever, wherein the angle is selected from a predefined range of angles.
[00012] In an embodiment, the bellows is dimensioned within a pre-defined range.
[00013] In an embodiment, a parking lever slot is adapted to receive the parking lever to enable application of a parking brake.
[00014] In an embodiment, the rubber boot is assembled from within a back plate of the auto-adjuster and the parking lever is inserted through the rubber boot.
[00015] In an embodiment, the rubber boot forming a sealing around the parking lever slot.
[00016] In an embodiment, the parking lever slot is enclosed by the rubber boot to prevent dust/mud entry.
[00017] Yet another aspect of the present disclosure pertains to a method for assembling a drum brake assembly. The method comprises of assembling a rubber boot into a back plate of an auto-adjuster and inserting a parking lever through the rubber boot creating a sealing around the parking lever slot.
[00018] The rubber boot effectively controls the dust/mud entry into back plate and the drum brake assembly through the parking lever slot. The rubber boot covers the lever while allowing the lever movement.
[00019] The rubber boot covers the parking lever in the drum brake assembly. It avoids the dust / mud entry into the drum brake assembly while allowing the free movement of the lever for brake actuation.
[00020] The rubber boot is designed with bellows to avoid dust/mud entry while allowing the lever to move for brake actuation. In an embodiment, the design of the rubber boot can be optimized such that the rubber boot can be accommodated in the existing slot available.
[00021] Optimized design of bellows is provided on the rubber boot to allow the lever movement during parking brake actuation while avoiding dust / mud entry.
BRIEF DESCRIPTION OF THE DRAWINGS
[00022] The detailed description of the present subject matter is described with reference to the accompanying figures. Same numbers are used throughout the drawings to reference like features and components.
[00023] Fig. 1 illustrates a left side view of an exemplary drum brake assembly 100, in accordance with an embodiment of the present subject matter.
[00024] Fig. 2 is a sectional view of the drum brake assembly 100 along an axis A-A illustrating positioning of the rubber boot 102.
[00025] Fig. 3 is a perspective view of the rubber boot 102 in accordance with an embodiment of the present disclosure.
[00026] Fig. 4A is a sectional view of the rubber boot 102 illustrating plurality of bellows 202-n on the rubber boot 102 in accordance with an embodiment of the present disclosure.
[00027] Fig. 4B is a top view of the parking lever 104 assembled within the rubber boot 102 in an embodiment of the present disclosure.
[00028] Fig. 5 illustrates a sectional view, along axis A-A of the rubber boot 102 in accordance with an embodiment of the present disclosure.

DETAILED DESCRIPTION
[00029] Through the parking lever slot dust / mud entry is observed into the drum brake assembly in field. Due to entry of mud, it can lead to problems such as reduction of braking efficiency, increased abrasions, reduction of brake shoe life, unexplained noise problems during braking. Therefore, it is an object of the present disclosure to ensure sealing of the parking lever slot to prevent dust/mud entry into the drum brake assembly.
[00030] The rubber boot is designed with bellows to avoid dust/mud entry while allowing the lever to move for brake actuation. In an embodiment, the design of the rubber boot can be optimized such that the rubber boot can be accommodated in the existing slot available. It is yet another object to provide a simple solution that is cost effective and can be implemented on to existing designs of the drum brake assembly.
[00031] Therefore, it is an object of the present invention to enable convenient operation of the parking brake lever while ensuring prevention of entry of foreign items within the slot for accommodating the parking lever.
[00032] Exemplary embodiments are described with reference to the accompanying drawings. Wherever convenient, the same reference numbers are used throughout the drawings to refer to the same or like parts. While examples and features of disclosed principles are described herein, modifications, adaptations, and other implementations are possible without departing from the spirit and scope of the disclosed embodiments. It is intended that the following detailed description be considered as exemplary only, with the true scope and spirit is indicated by the following claims.
[00033] The embodiments of the present invention will now be described in detail with reference to a wheel along with the accompanying drawings. However, the present invention is not limited to the present embodiments. The present subject matter is further described with reference to accompanying figures. It should be noted that the description and figures merely illustrate principles of the present subject matter. Various arrangements may be devised that, although not explicitly described or shown herein, encompass the principles of the present subject matter. Moreover, all statements herein reciting principles, aspects, and examples of the present subject matter, as well as specific examples thereof, are intended to encompass equivalents thereof.
[00034] Referring now to Fig. 1, that illustrates a left side view of an exemplary drum brake assembly 100, in accordance with an embodiment of the present subject matter, a drum brake assembly 100 is disclosed. The drum brake assembly includes a pair of brake shoes (not shown), the pair of brake shoes are operable by a brake cam lever (not shown). A face cam (not shown) arrangement transfers rotary actuating force from a brake cam lever (not shown) to the pair of brake shoes. The Drum brakes consists of a pair of brake shoes (not shown), outer lining around the pair of brake shoes (not shown), drum wheel (not shown). Automatic adjuster 200 for a brake device of a vehicle includes the components such as the brake cam which may be a rod like structure accommodating the other components of auto-adjuster. The auto-adjuster 200 is disclosed within the brake drum assembly. A rubber boot 102 is disposed from within the back plate 204 of the adjuster. A parking lever 104 is accommodated within the rubber boot 102. The rubber boot 102 has a pre-defined elastic modulus and is composed of rubber having a pre-defined elasticity. The rubber boot 102 is assembled from within a back plate 204 of the auto-adjuster and the parking lever is inserted through the rubber boot 102. Fig. 2 is a sectional view of the drum brake assembly 100 along an axis A-A illustrating positioning of the rubber boot 102.
[00035] Fig. 3 is a perspective view of the rubber boot 102 in accordance with an embodiment of the present disclosure.
[00036] Fig. 4A is a sectional view of the rubber boot 102 illustrating plurality of bellows 202-n on the rubber boot 102 in accordance with an embodiment of the present disclosure. In this illustrated embodiment, three bellows can be seen 202-1, 202-2 and 202-3. The rubber boot 102 is configured with a plurality of bellows 202-n disposed along an axial length of the rubber boot 104.
[00037] The rubber boot 102 is disposed at an angle relative to a horizontal axis of the parking lever 104, wherein the angle is selected from a predefined range of angles. The plurality of bellows 202-n is dimensioned within a pre-defined range.
[00038] The parking lever slot is adapted to receive the parking lever 104 to enable application of parking brake. The rubber boot 102 forms a sealing around the parking lever slot. The rubber boot 102 is hollow and is adapted to receive a parking lever through.
[00039] Fig. 4B is a sectional top view of the parking lever 104 along the axis A-A. The parking lever 104 can be seen assembled within the rubber boot 102.
[00040] Fig. 5 illustrates a sectional side view, along the axis A-A of the rubber boot 102 in accordance with an embodiment of the present disclosure.
[00041] The parking lever slot is enclosed by the rubber boot 102 to prevent dust/mud entry.
[00042] An aspect of the present disclosure pertains to a method for assembling a drum brake assembly 100. The method includes assembling a rubber boot 102 into a back plate 204 of an auto-adjuster 200 and inserting a parking lever 104 through the rubber boot 102 creating a sealing around a parking lever slot.
[00043] If the dust/mud/water entry is avoided into brake assembly, brake shoe and brake drum life is improved, which improves the brake performance and durability. Further, the brake squeal noise can also be reduced.
[00044] This rubber boot design avoids dust / mud entry into the back plate, which in turn helps to improve brake shoe and brake drum durability life and avoids brake noise.
[00045] The Brake shoe life is increased because of reduced foreign particles within the drum brake assembly.
[00046] The drum brake assembly also leads to a reduction in noise because of reduced foreign particles within the drum brake assembly.
[00047] In view of the above, the claimed limitations as discussed above are not routine, conventional, or well understood in the art, as the claimed limitations enable the above solutions to the existing problems in conventional technologies.
[00048] The present subject matter is described using a drum brake assembly for a vehicle, a three-wheeled or a four wheeled vehicle whereas the claimed subject matter can be used in any other type of application employing above-mentioned drum brake assembly, with required changes and without deviating from the scope of invention. Further, it is intended that the disclosure and examples given herein be considered as exemplary only.
[00049] The terms “an embodiment”, “embodiment”, “embodiments”, “the embodiment”, “the embodiments”, “one or more embodiments”, “some embodiments”, and “one embodiment” mean “one or more (but not all) embodiments of the invention(s)” unless expressly specified otherwise. The terms “including”, “comprising”, “having” and variations thereof mean “including but not limited to”, unless expressly specified otherwise. The terms “a”, “an” and “the” mean “one or more”, unless expressly specified otherwise.
[00050] Finally, the language used in the specification has been principally selected for readability and instructional purposes, and it may not have been selected to delineate or circumscribe the inventive subject matter and is therefore intended that the scope of the invention be limited not by this detailed description, but rather by any claims that issue on an application based here on. Accordingly, the embodiments of the present invention are intended to be illustrative, but not limiting, of the scope of the invention, which is set forth in the following claims.
[00051] While various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.
[00052] A person with ordinary skills in the art will appreciate that the systems, modules, and sub-modules have been illustrated and explained to serve as examples and should not be considered limiting in any manner. It will be further appreciated that the variants of the above disclosed system elements, modules, and other features and functions, or alternatives thereof, may be combined to create other different systems or applications.
[00053] While the present disclosure has been described with reference to certain embodiments, it will be understood by those skilled in the art that various changes may be made, and equivalents may be substituted without departing from the scope of the present disclosure. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the present disclosure without departing from its scope. Therefore, it is intended that the present disclosure not be limited to the particular embodiment disclosed, but that the present disclosure will include all embodiments falling within the scope of the appended claims.
[00054] It is to be understood that the aspects of the embodiments are not necessarily limited to the features described herein. Many modifications and variations of the present subject matter are possible in the light of above disclosure. Therefore, within the scope of claims of the present subject matter, the present disclosure may be practiced other than as specifically described.

, C , Claims:We claim:
1. A drum brake assembly (100), the drum brake assembly (100) comprising:
a pair of brake shoes, the pair of brake shoes being operable by a brake cam lever;
a face cam, the face cam being configures to transfer rotary actuating force from the brake cam lever to the pair of brake shoes;
a rubber boot (102);
a parking lever (104), the parking lever (104) being accommodated within the rubber boot (102);
wherein the rubber boot (102) having a pre-defined elastic modulus.

2. The brake drum assembly (100) as claimed in claim 1, wherein the brake drum assembly (100) comprising an auto-adjuster (200).

3. The drum brake assembly (100) as claimed in claim 1, wherein, the rubber boot (102) being a hollow structure and configured with a plurality of bellows (202-n) disposed along an axial length of the rubber boot (104).

4. The drum brake assembly (100) as claimed in claim 1, wherein the rubber boot (102) being disposed at an angle relative to a horizontal axis of the parking lever (104), wherein the angle being selected from a predefined range of angles.

5. The drum brake assembly (100) as claimed in claim 1, wherein the plurality of bellows (202-n) being dimensioned within a pre-defined range.

6. The drum brake assembly (100) as claimed in claim 1, wherein a parking lever slot being adapted to receive the parking lever (104) to enable application of parking brake.

7. The drum brake assembly (100) as claimed in claim 2, wherein the rubber boot (102) being assembled from within a back plate (204) of the auto-adjuster and the parking lever being inserted through the rubber boot (102).

8. The drum brake assembly (100) as claimed in claim 7, wherein the rubber boot (102) forming a sealing around the parking lever slot.

9. The drum brake assembly (100) as claimed in claim 1, wherein the parking lever slot being enclosed by the rubber boot (102) to prevent dust/mud entry.

10. A method for assembling a drum brake assembly (100), the method comprising:
assembling a rubber boot (102) into a back plate (204) of an auto-adjuster (200); and,
inserting a parking lever (104) through the rubber boot (102) creating a sealing around a parking lever slot.