Claims:
1. A system for drum brake liner replacement indicator, said system comprising:
at least one brake assembly further comprising at least one drum brake with at least one brake lining (2) mounted on at least two brake shoe sub assembly (1) having a cam end (5) and an anchor end (6) and positioned against the inside surface of the drum brake adapted to apply brakes to at least one moving wheel of a vehicle;
at least one S-cam (3) positioned between the at least two Brake shoe sub assembly (1);
at least one sensor or at least one wire (4) coupled with a plurality of electrical connections and positioned at preset gap between the at least two Brake shoe sub assembly (1);
wherein the brake lining (2) is having a predetermined thickness for gradually wearing away as the brake of the vehicle is applied; and
wherein as the brake lining (2) wears out, the advancement by rotation of the at least one S-cam (3) lifts the at least two Brake shoe sub assembly (1) apart from each other which in turn increases the gap between the at least two Brake shoe sub assembly (1) resulting in activating the at least one sensor or breaking the at least one wire (4) connected to the plurality of electrical connections adapted to send signal for indication for replacement need of the brake lining (2)of the drum brake.

2. The system as claimed in claim 1, wherein the system is linked to a data management or fleet management system adapted to ensure the indications/ alerts on time for replacement of the brake linings (2) of the drum brake.

3. The system as claimed in claim 1, wherein the system can be employed to multiple points at the Brake shoe sub assembly (1) of the drum brake.

4. The system as claimed in claim 1, wherein the plurality of electrical connections is an electrical circuit or a wiring connection to a bulb indictor or to a IOT platform or to a Vehicle system for related alerts.

5. The system as claimed in claim 1, wherein the at least one sensor or at least one wire (4) are positioned either at the cam end or at the anchor end of the at least two Brake shoe sub assembly (1) carrying the brake lining (2).

6. The system as claimed in claim 1, wherein the system comprises at least two cam rollers (7) adapted to move the at least one S-cam (3).
, Description:
TECHNICAL FIELD OF THE INVENTION
The present invention relates to the field of automotive engineering and more particularly to the liner replacement sensing systems for the brake linings of vehicle drum brake or indication system for the liner replacement requirement.

BACKGROUND OF THE INVENTION
Most motor vehicles include a Drum brake system having a set of Brake shoe sub assembly assemblies for retarding the rotation of the Drum which is mounted to the wheels of the vehicle when the brakes are applied. Typically, each Brake shoe sub assembly includes a brake lining made of a friction material which gradually wears away during brake applications. After numerous brake applications, the brake lining wears below a critical material thickness and, therefore, must be replaced. As a result, the brake lining must be periodically inspected for excessive wear. To eliminate time-consuming and visual inspections of the brake lining, the prior art has taught several types of brake lining replacement sensing for indicating when the brake lining must be replaced.

Document US4250978 A discloses a brake lining wear sensor produces an audible signal when it engages a rotating brake drum upon a predetermined amount of lining wear. The sensor is disposed within a groove between a friction lining and a Brake shoe sub assembly rim. Portions of the sensor project away from a body portion and engage the rotating brake drum to produce the warning signal. The projecting portions also cooperate with surfaces of the brake shoe sub assembly rim or the friction lining to retain the sensor within the groove.

Document US5559286 A discloses a sensor which responds to both changes in working length and temperature is embedded in a friction lining to provide a signal indicative of both wear and temperature to an electronic control unit which interprets long term averaged change in the sensor resistance measured when the vehicle is stationary as lining wear and short term changes in sensor resistance as representative of lining temperature.

Document US5848672 A discloses a wear sensing system for the brake linings of a vehicle. Since the sensors are mounted within the brake mechanism, the reduction in the disc thickness must be taken into account to supply an accurate reading. A non-volatile memory stores the position of the brake before replacement and is compared to the position after replacement. However, the latter reading is established only after a predetermined number of brake applications to take up any starting clearances.

Document US6250429 B1 discloses a brake shoe sub assembly which includes a brake lining and a brake lining wear sensor. The brake lining has a predetermined thickness which gradually wears away as the brake shoe sub assembly is used to brake a vehicle. The brake lining wear sensor has a pair of spaced electrical conductors and an electrical resistance located across the pair of spaced conductors for indicating the thickness of the brake lining. The brake lining wear sensor is positioned to wear away concurrently with the brake lining, thereby continuously changing the electrical resistance across the pair of spaced conductors. In this manner, the electrical resistance across the pair of spaced conductors is used to determine the thickness of the brake lining.

Although the above mentioned prior arts discloses wearing system for detecting the wearing of brake lining in vehicles but still the existing systems are very complex and less user friendly. Moreover, the existing brake lining wear sensing systems are expensive. Further, in India at present no such mechanism exists on the drum brake liners resulting in the physical verification needs. At present no such commercialized system of Liner replacement alert is available in the industry for the Drum brakes on commercial vehicles in India. Even though there are pad wear sensors available in the industry for the disc brakes and not application to the brake drum liner replacement requirements. Majority of the physical verifications are done only post the concern of less braking is observed or any abnormality is being reported by the drivers.

The above described prior art system suffers from many disadvantages, which the instant invention effectively eliminates. For this reason, there is a dire need to provide an improved system for drum brake liner replacement indicator to overcome the problems of the prior art.

SUMMARY OF THE INVENTION
The following disclosure presents a simplified summary of the invention in order to provide a basic understanding of some aspects of the invention. This summary is not an extensive overview of the present invention. It is not intended to identify the key/critical elements of the invention or to delineate the scope of the invention. Its sole purpose is to present some concept of the invention in a simplified form as a prelude to a more detailed description of the invention presented later.

An object of the present invention is to overcome the problems of prior art.

An object of the present invention is to provide an improved system for drum brake liner replacement indicator.

An object of the present invention is to provide a cost effective system for drum brake liner replacement indicator.

Yet another object of the present invention is to provide a system for drum brake liner replacement indicator which alerts the drivers or the fleet operator upfront and improves the safety of the driver and the vehicles.

One aspect of the present disclosure is to provide an improved system for drum brake liner replacement indicator. The invention discloses a sensor or wire coupled with the electrical connections and positioned between the brake shoe sub assembly which indicates as soon as the liner reaches closer to the usable liner thickness alerting the driver/fleet data management for the replacement need.

In an implementation of the aspect described above, the invention discloses a system for drum brake liner replacement indicator comprising at least one brake assembly further comprising at least one drum brake with at least one brake lining mounted on at least two Brake shoe sub assembly having a cam end and an anchor end and positioned against the inside surface of the drum brake adapted to apply brakes to at least one moving wheel of a vehicle, at least one S-cam positioned between the at least two brake shoe sub assembly, at least one sensor or at least one wire coupled with a plurality of electrical connections and positioned at preset gap between the at least two Brake shoe sub assembly, wherein the brake lining is having a predetermined thickness for gradually wearing away as the brake of the vehicle is applied and wherein as the brake lining wears out, the advancement by rotation of the at least one S-cam lifts the at least two brake shoe sub assembly apart from each other which in turn increases the gap between the at least two brake shoe sub assembly resulting in activating the at least one sensor or breaking the at least one wire connected to the plurality of electrical connections adapted to send signal for indication for replacement need of the brake lining of the drum brake.

In an implementation, the system is linked to a data management or fleet management system adapted to ensure the indications/ alerts on time for replacement of the brake linings of the drum brake.

In an implementation, the plurality of electrical connections is an electrical circuit or a wiring connection to a bulb indictor or to a IOT platform or to a Vehicle system for related alerts.

In an another implementation, the at least one sensor or at least one wire are positioned either at the cam end or at the anchor end of the at least two brake shoe sub assembly carrying the brake lining.

Other aspects, advantages, and salient features of the invention will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses exemplary embodiments of the invention.

BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS
The above and other aspects, features and advantages of the embodiments of the present disclosure will be more apparent in the following description taken in conjunction with the accompanying drawings, in which:

Figure 1 (a) Illustrates the schematic view of the system for drum brake liner replacement with a sensor placed between the pair of brake shoe sub assembly, according to one of the embodiments of the present invention.

Figure 1(b) Illustrates the magnified view of the system for drum brake liner replacement with a sensor or wire placed between the pair of brake shoe sub assembly, according to one of the embodiments of the present invention.

Persons skilled in the art will appreciate that elements in the figures are illustrated for simplicity and clarity and may not have been drawn to scale. For example, the dimensions of some of the elements in the figure may be exaggerated relative to other elements to help to improve understanding of various exemplary embodiments of the present disclosure. Throughout the drawings, it should be noted that like reference numbers are used to depict the same or similar elements, features, and structures.

DETAILED DESCRIPTION OF THE PRESENT INVENTION
The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of various embodiments of the present disclosure as defined by the claims and their equivalents. It includes various specific details to assist in that understanding, but these are to be regarded as merely exemplary. Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the various embodiments described herein can be made without departing from the scope and spirit of the present disclosure. In addition, descriptions of well-known functions and constructions may be omitted for clarity and conciseness.

The terms and words used in the following description and claims are not limited to the bibliographical meanings, but, are merely used by the inventor to enable a clear and consistent understanding of the present disclosure. Accordingly, it should be apparent to those skilled in the art that the following description of various embodiments of the present disclosure is provided for illustration purpose only and not for the purpose of limiting the present disclosure as defined by the appended claims and their equivalents.

It is to be understood that the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, a reference to "a component surface" includes a reference to one or more of such surfaces.

All terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which various embodiments belong. Further, the meaning of terms or words used in the specification and the claims should not be limited to the literal or commonly employed sense, but should be construed in accordance with the spirit of the disclosure to most properly describe the present disclosure.

The terminology used herein is for the purpose of describing particular various embodiments only and is not intended to be limiting of various embodiments. As used herein, the singular forms "a," "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising" used herein specify the presence of stated features, integers, steps, operations, members, components, and/or groups thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, members, components, and/or groups thereof. Also, Expressions such as "at least one of," when preceding a list of elements, modify the entire list of elements and do not modify the individual elements of the list.

The present invention provides an improved system for drum brake liner replacement indicator. The sensor in this invention is assembled on the Brake shoe sub assembly at preset gap of the Brake shoe sub assembly within the Brake assembly other side with the electrical wiring. The Sensor will get released as the liner is worn out which in turn has resulted in the increased or decreased gap between the Brake shoe sub assembly of the same brake providing the electrical signal for indication.

Reference is made to figure 1. The technical components as shown in the figure are:

1 – Brake shoe sub assembly
2- Brake lining
3- S-cam
4- Sensor or wire
5- Cam end
6.-Anchor end
7. Cam rollers

The system disclosed in the present invention will help is alerting the drivers upfront and improves the safety of the driver and the vehicles. The system can also be linked to various data management or fleet management systems to ensure the indications/ alerts on time for the replacement liners resulting the better on road brake functioning and safety.

S-Cam brake with new liners fitted shown in figure 1(a) and 1(b), where the distance between the Brake shoe sub assembly is at a certain dimension (called ‘X’), considered between any two points, anywhere in the Brake shoe sub assembly or can be the distance considered between the two Cam rollers (7).

As the liner wears out, the advancement by rotation of the S-cam will lift the Brake shoe sub assembly apart from each other, making the dimension `X` vary. Dimension `X` will increase above the anchor axis of the shoe & `X` will decrease below the anchor axis of the shoe as shown in figure 1 (a) and 1 (b).

Sensor or wire connected between the two Brake shoe sub assembly, either at the cam end (5) or at the anchor end (6) of the Brake shoe sub assembly (1). When the Brake liner (2) wears out and reaches the recommended replacement stage, the sensor (4) will be activated or the wire (4) will break; which will be converted to electronic signal to for the indication for liner replacement.

In an embodiment of the present invention, the system for drum brake liner replacement indicator comprising at least one brake assembly further comprising at least one drum brake with at least one brake lining (2) mounted on at least two Brake shoe sub assembly (1) having a cam end (5) and an anchor end (6) and positioned against the inside surface of the drum brake adapted to apply brakes to at least one moving wheel of a vehicle, at least one S-cam (3) positioned between the at least two Brake shoe sub assembly sub assembly (1), at least one sensor or at least one wire (4) coupled with a plurality of electrical connections and positioned at preset gap between the at least two Brake shoe sub assembly (1), wherein the brake lining (2) is having a predetermined thickness for gradually wearing away as the brake of the vehicle is applied and wherein as the brake lining (2) wears out, the advancement by rotation of the at least one S-cam (3) lifts the at least two Brake shoe sub assembly (1) apart from each other which in turn increases the gap between the at least two Brake shoe sub assembly (1) resulting in activating the at least one sensor or breaking the at least one wire (4) connected to the plurality of electrical connections adapted to send signal for indication for replacement need of the brake lining (2)of the drum brake.

In an embodiment of the present invention, the system is linked to a data management or fleet management system adapted to ensure the indications/ alerts on time for replacement of the brake linings (2) of the drum brake.

In an embodiment of the present invention, the plurality of electrical connections is an electrical circuit or a wiring connection to a bulb indictor or to a IOT platform or to a Vehicle system for related alerts.

In an embodiment of the present invention, the at least one sensor or at least one wire (4) are positioned either at the cam end or at the anchor end of the at least two Brake shoe sub assembly (1) carrying the brake lining (2).

In an embodiment of the present invention, the system can be employed to multiple points at the brake lining (2) of the drum brake or at multiple brake lining of the drum brake (1).

In an embodiment of the present invention, the system comprises at least two cam rollers (7) adapted to move the at least one S-cam (3).

Some of the non-limiting advantages of the present invention are as follows:
1. The system is more economical and user friendly as compared to the existing wear monitoring systems.
2. It alerts the drivers upfront and improves the safety of the driver and the vehicles.
3. The system can be easily linked to various data management or fleet management systems to ensure the indications/alerts on time for the replacement liners resulting in the better on road brake functioning and safety.
4. The system can be employed to multiple points at the Brake shoe sub assembly of the drum brake.

Those skilled in the art will recognize other use cases, improvements, and modification to the embodiments of the present disclosure. All such improvements and other use-cases are considered within the scope of the concepts disclosed herein.