FORM 2
THE PATENTS ACT 1970
[39 OF 1970]
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
[See section 10; rule 13]
TITLE: “AN AUTOMATED BRAKE ADJUSTMENT SYSTEM AND A METHOD
THEREOF”
Name and Address of the Applicant: TATA MOTORS LIMITED: of Bombay House, 24 Homi Mody Street, Hutatma Chowk, Mumbai – 400 001, Maharashtra, India
Nationality: Indian
The following specification particularly describes the nature of the invention and the manner in which it is to be performed.

TECHNICAL FIELD
Present disclosure generally relates to brake systems for automobiles. Particularly, but not exclusively, the present disclosure relates to a system and a method for automatically adjusting a gap between brake liners and a brake drum of a braking system.
BACKGROUND OF THE DISCLOSURE
Vehicles nowadays have become a prime mode of transportation. Many users utilize a wide variety of vehicles right from passenger cars to commercial vehicles to move people or goods from one place to another. Vehicles are equipped with various braking systems to reduce the speed of the vehicle or to stop the vehicle. Based on medium used to transfer brake application force, various types of braking system are used in the vehicles such as pneumatic braking system, hydraulic braking system, and electromagnetic braking system.. These braking systems use frictional force generated by frictional contact between brake liners and a moving brake drum or disc of the braking system to stop the vehicle.
Typically, a pneumatic braking system as shown in figure 1 (prior art) comprises a brake chamber connected to a brake pedal through a brake valve at one end and to a push rod at another end. The brake valve receives compressed air from a storage tank. The push rod is further connected to an input shaft of a slack adjuster. An output shaft of the slack adjuster is connected to the brake drum via a cam shaft. The cam shaft includes an S-cam connected to a brake liner to displace the brake liner within the brake drum upon rotation of the cam shaft for braking. Upon actuation of the brake pedal, the compressed air enters into the vacuum chamber to linearly displace the push rod which rotates the cam shaft to contact the brake liners with the brake drum. Further, the slack adjuster has an adjusting mechanism with a worm wheel and a pinion gear arrangement. The adjuster mechanism is configured to adjust and maintain a fixed gap between the brake liner and the brake drum to compensate increase in gap which may occur due to wear of the brake liners. However, this adjustment can be made in a fixed range, for example from 0.3-1mm based on gear pitch values of the adjustment mechanism.
Further, upon frequent braking at higher vehicle speeds and during downhill travel, the brake drum may subject to thermal expansion which leads to increase in the gap between the brake liners and the drum. At this point the slack adjuster adjusts the gap to a fixed range. Now, when the brake drum contracts after thermal expansion, the position of the brake liners remains same and therefore the brake drum contacts the brake liners without any gap. This leads to brake

dragging and the braking as well vehicle fuel efficiency decreases. Also, dragging of brake increases brake temperature which shall lead to fire accidents and also reduces liner life, as increases down time of vehicle.
The present disclosure is directed to overcome one or more limitations stated above or other such limitations associated with the prior art.
SUMMARY OF THE DISCLOSURE
One or more shortcomings of conventional systems are overcome, and additional advantages are provided through a system and a method as claimed in the present disclosure. Additional features and advantages are realized through the techniques of the present disclosure. Other embodiments and aspects of the disclosure are described in detail herein and are considered as a part of the claimed disclosure.
In one non-limiting embodiment of the disclosure, a system for automatically adjusting the liner-drum gap of a brake is disclosed. The system comprises a brake pedal connected to a brake chamber through a brake valve. An adjuster unit is coupled to the brake chamber by a push rod. A cam shaft is connected to the adjuster unit and the cam shaft comprises a cam at one end, wherein the cam is defined in a brake drum. Further, an actuator is integrated to the adjuster unit to selectively actuate the adjuster unit. A plurality of sensors are connected to the pushrod ,the adjuster unit and the cam shaft. The plurality of sensors detects and sends a signal upon actuation of the brake pedal. The system further comprises a control unit in communication with the plurality of sensors and the actuator. The control unit is configured to receive a signal from a plurality of sensors to determine displacement of the push rod with respect to time. Receive a signal from a plurality of sensors and the control unit is configured to determine slope of displacement of the push rod and a change in slope of displacement of the push rod. Record a travel and time stamp at which the determined change in slope of displacement of the push rod has taken place. Determine a gap between a brake liner and the brake drum based on the determined change in displacement of the pushrod with respect to time and travel and time stamp. The control unit sends an actuation signal to the actuator to selectively adjust the gap, if the determined gap is more than a predefined gap and less than the predefined gap.
In an embodiment of the disclosure, the cam of the cam shaft is configured to be in contact with the brake liner to displace the brake liner within the brake drum.

In an embodiment of the disclosure, the adjuster unit comprises a worm shaft coupled to a gear assembly of the actuator to adjust the gap upon rotation of the gear assembly.
In an embodiment of the disclosure, the control unit receives the signal from the plurality of sensors corresponding to a linear displacement of the push rod ,an angular displacement of the adjuster and a rotation angle of the cam shaft upon actuation of the brake pedal.
In an embodiment of the disclosure, the change in displacement of the push rod and the adjuster is proportional to an increase in the brake pedal movement during braking.
In an embodiment of the disclosure, the control unit determines the gap based on change of angular displacement of the adjuster unit.
In an embodiment of the disclosure, the control unit determines the gap based on change of rotational angle of the cam shaft.
In an embodiment of the disclosure, the control unit compares one or more values of the change in slope of displacement of the push rod with respect to time with a set of predefined values to determine the gap and operates the actuator to selectively adjust the gap if the determined gap deviates from the set of predefined values.
In an embodiment of the disclosure, the set of predefined values correspond to a displacement of the push rod when the brake liners come into contact with the brake drum with respect to time.
In an embodiment of the disclosure, the linear displacement of the push rod (2) is in the range of 0 to 65 mm, angular displacement of the adjuster (3) and rotational angle of the cam shaft (9) are in the range of 0 – 90°.
In an embodiment of the disclosure, the adjuster unit is actuated by the actuator to adjust the gap between the brake liner and the brake drum when the vehicle speed is less than 5 kmph and when the brakes are in disengaged condition.
In an embodiment of the disclosure, the plurality of sensors is at least one of a linear variable differential transducer (LVDT), a linear potentiometer, a rotary encoder and an angle sensor.
In another non-limiting embodiment of the disclosure, a method for automatically adjusting a braking system. The method comprising receiving, by a control unit, a signal corresponding to

a change in slope of displacement of a push rod with respect to time from a plurality of sensors associated with the push rod. The push rod is coupled to an adjuster unit which is connected to a brake drum. Recording, by a control unit, a travel and time stamp at which a change in slope of displacement of the push rod has taken place. Determining, by a control unit, a gap between a brake liner and the brake drum based on the determined change in slope of displacement of the pushrod and the travel and time stamp at which the change in slope of displacement has taken place. The control unit sends an actuation signal to the actuator to selectively adjust the gap if the determined gap is more or less than a predefined gap.
It is to be understood that the aspects and embodiments of the disclosure described above may be used in any combination with each other. Several of the aspects and embodiments may be combined together to form a further embodiment of the disclosure.
The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.
BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS
The novel features and characteristic of the disclosure are set forth in the appended claims. The disclosure itself, however, as well as a mode of use, further objectives and advantages thereof, will best be understood by reference to the following detailed description of an embodiment when read in conjunction with the accompanying drawings. One or more embodiments are now described, by way of example only, with reference to the accompanying drawings wherein like reference numerals represent like elements and in which:
Fig. 1 (Prior Art) illustrates a front view of a prior art depicting a pneumatic braking system.
Fig. 2 illustrate a schematic layout of an automated brake adjustment system in accordance with an embodiment of the present disclosure.
Fig. 3 illustrates a front sectional view of an adjuster unit used in accordance with an embodiment of the present disclosure.
Fig. 4 illustrates a perspective view showing arrangements of components depicted in the system of figure. 2.

Fig. 5 illustrates a side view of the automated brake adjustment system, in accordance with an embodiment of the present disclosure.
Fig. 6 illustrates a flow diagram of a method showing steps involved in the automated brake adjustment system depicted in figure. 2.
Fig. 7 illustrates a flow chart showing conditional parameters to activate the automated brake adjustment system of figure. 2, in accordance with an embodiment of the present disclosure.
The figures depict embodiments of the disclosure for purposes of illustration only. One skilled in the art will readily 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
While the embodiments in the disclosure are subject to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the figure and will be described below. It should be understood, however, that it is not intended to limit the disclosure to the particular forms disclosed, but on the contrary, the disclosure is to cover all modifications, equivalents, and alternative falling within the scope of the disclosure.
It is to be noted that a person skilled in the art would be motivated from the present disclosure and modify various features of the method and the system, without departing from the scope of the disclosure. Therefore, such modifications are considered to be part of the disclosure. Accordingly, the drawings show only those specific details that are pertinent to understand the embodiments of the present disclosure, so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skilled in the art having benefit of the description herein. Also, the method of the present disclosure may be employed in a variety of vehicles having different specification.
The terms “comprises”, “comprising”, or any other variations thereof used in the disclosure, are intended to cover a non-exclusive inclusion, such that of a system that comprises a list of components does not include only those components but may include other components not expressly listed or inherent to such system, method, or assembly, or device. In other words, one or more elements in a system or device proceeded by “comprises… a” does not,

without more constraints, preclude the existence of other elements or additional elements in the system or device.
Embodiments of the present disclosure discloses an automated brake adjustment system of a vehicle to maintain optimum gap between a brake liner and a brake drum. Conventionally, a pneumatic brake system includes a brake chamber connected to a push rod. The brake chamber is connected to a brake pedal through a brake valve. The brake valve receives compressed air from a storage tank supplied by a compressor. Upon actuation of the brake pedal, the compressed air is released from the brake valve and enters into the brake chamber to linearly displace the push rod. The push rod is coupled to a slack adjuster which is connected to a cam shaft. The cam shaft is disposed within the brake drum and is in contact with the brake liners. The push rod actuates the slack adjuster to rotate the cam shaft to displace the brake liners within and toward the brake drum. This enables frictional contact of the brake liners with the brake drum to decelerate and stop the vehicle. However, repeated braking of the vehicle may increase wear of the brake liners which eventually increases slackness within the brake drum with increase in the displacement of the push rod. To counter this, the slack adjuster includes an adjusting mechanism with a worm wheel and pinion gear arrangement. The adjuster mechanism is configured to adjust and maintain the fixed gap between the brake liner and the brake drum to compensate increase in gap which may occur due to wear of the brake liners. However, this adjustment is carried out in a fixed range and only in forward direction or rotation of the worm shaft within the slack adjuster. In an embodiment, this adjustment may also be carried out manually as well by a trained or skilled person. The manual slack adjuster may comprise of operation of the worm shaft that is rotated manually using a suitable tool to adjust the gap (a) when the slack adjuster is stationary. In an embodiment, the suitable tool may be a wrench.
In view of the above, upon frequent braking at higher vehicle speeds, the brake drum is subjected to thermal expansion which leads to increase in the gap between the brake liners and the drum. At this point, the slack adjuster adjusts the gap to a fixed range. Now, when the brake drum contracts, the gap decreases which leads to brake dragging and the braking efficiency decreases. Moreover, this may lead to major accidents and frequent replacement of the slack adjuster increases maintenance cost of the braking system.
In view of this, embodiments of the present disclosure disclose a system and method for automatically adjusting a gap between a brake liner and a brake drum to maintain optimum gap

in order to enable effective braking of the vehicle in all operating conditions. The system and method may be employed in heavy duty vehicles as well as light duty commercial vehicles. The system comprises a brake pedal connected to a brake chamber through a brake valve. An adjuster unit is coupled to the brake chamber by a push rod. A cam shaft is connected to the adjuster unit and the cam shaft comprises a cam at one end, wherein the cam is defined in a brake drum. Further, an actuator is integrated to the adjuster unit to selectively actuate the adjuster unit. A plurality of sensors are connected to the pushrod and the adjuster unit. The plurality of sensors are configured to detect and send a signal upon actuation of the brake pedal. A control unit is communicatively coupled to the plurality of sensors and the actuator. The control unit is configured to receive a signal from a plurality of sensors to determine the slope of displacement of the push rod and the change in slope of displacement of the push rod. The control unit also records travel and time stamp at which a change in slope of displacement of the push rod has taken place and determines a gap between the brake liners and the brake drum. The control unit determines the gap based on the determined change in slope of displacement of the pushrod and the travel and time stamp at which the change in slope of displacement of the push rod has occurred. Lastly, the control unit sends an actuation signal to the actuator to selectively adjust the gap.
Further, the present disclosure also discloses a method of adjusting a method for automatically adjusting a brake device. The method comprises the steps of receiving, by a control unit, a signal corresponding to a displacement of a push rod and a slope of displacement of the push rod from a plurality of sensors associated with the push rod. The push rod is coupled to an adjuster unit which is connected to a brake drum. A control unit records, a travel and time stamp at which a change in slope of displacement of the push rod has occurred. Followed by, determining gap between a brake liner and the brake drum based on the determined change in displacement of the pushrod and the travel and time stamp of the change in displacement of the push rod.
The following paragraphs describe the present disclosure with reference to Figures. 1 to 5. In the figures, the same element or elements which have similar functions are indicated by the same reference signs.
Figure. 2 illustrates a schematic layout of an automated brake adjustment system of a vehicle. The system comprises a control unit (10), communicatively coupled to a plurality of sensors (7) and an actuator (4). The plurality of sensors (7) are connected to a push rod (2), an adjuster

unit (3) and a cam shaft (9). The plurality of sensors (7) are configured to detect linear displacement of the push rod (2). an angular displacement of the adjuster unit and a rotational angle of the cam shaft (9). In an embodiment, the plurality of sensors (7) is at least one of linear variable differential transducer (LVDT), angular sensor, linear potentiometer and rotary encoder. The adjuster unit (3) includes an input end and an output end. The input and output ends are defined with a provision to receive the push rod (2) and the cam shaft (9) at both ends respectively. In an embodiment, the adjuster unit (3) is a slack adjuster coupled to the brake drum (8) through a cam shaft (9) (fig. 4) at its output end. However, this cannot be considered as a limitation and any type of adjuster may be used to convert linear motion of the push rod (2) into rotary motion of the cam shaft (9). The adjuster unit (3) is connected to the push rod (2) at the input end and is configured to convert linear motion of the push rod (2) into a rotary motion of the cam shaft (9). The cam shaft (9) includes an S-cam (12) at one end that is disposed within the brake drum (8). The brake chamber (1) includes a diaphragm (18) and a spring member (16) that are in contact with the push rod (2). The diaphragm (18) actuates the push rod (2) upon actuation of the brake pedal (15) by the user. The S-cam (12) is in contact with the brake liners (5) such that rotation of the S-cam (12) displaces the brake liners (5) within an inner surface of the brake drum (8).The brake chamber (1) receives compressed air through a brake valve (14) upon operation of the brake pedal (15). The brake valve (14) is operated to enable or disable the supply of compressed air into the brake chamber (1). In an embodiment, the brake valve (14) is connected to a storage tank (21) having compressed air. Upon actuation of the brake pedal (15), the compressed air pushes the diaphragm (18) to actuate the push rod (2) and the push rod (2) is retracted by the spring (16) upon release of the brake pedal (15). This linear actuation of the push rod (2) further actuates the adjuster unit (3) angularly to rotate the cam shaft (9) such that, the S-cam (12) pivots about its axis to enable frictional contact of the brake liners (5) with the inner surface of the brake drum (8) to achieve braking of the vehicle.
Now referring to figure. 3, the adjuster unit (3) [hereinafter referred to as adjuster (3)] is defined with a housing (3d) having a provision at its top end and a bottom end to receive the push rod (2) and the cam shaft (9) respectively. The adjuster (3) includes a gear assembly (30) disposed within the housing (3d) at a central portion of the adjuster (3) and this cannot be considered as a limitation. The gear assembly (30) includes a worm wheel (3b) that has a first gear teeth (32) defined on an outer circumferential surface. The gear assembly (30) further includes a worm shaft (3a) that has a longitudinal central axis (A-A). A portion of the worm

shaft (3a) is defined with a clutch worm wheel (3e) with a second gear teeth (36). A pinion gear (3f) with the third gear teeth (38) is disposed between the clutch worm wheel (3e) and the worm wheel (3b). The third gear teeth (38) of the pinion gear (3f) meshes with the worm wheel (3b). The pinion gear includes a fourth gear teeth (40) having a ratchet wheel mechanism (not shown) at its output end. The fourth gear teeth (40) is meshed with the clutch worm wheel (3e). The worm wheel (3b), pinon gear (3f) and the clutch worm wheel (3e) are rotated in tandem upon actuation of the S -cam (12) [by pressing the brake pedal (15)]. The gear assembly (30) is covered with a cover plate (3c) to support the gear assembly (30). In an embodiment, the cover plate (3c) is assembled with any suitable fastening means such as nuts and bolts, screws etc. During brake application, the rotational input to the pinion gear (3f) is in a free-wheel direction, and thus the second gear teeth (26) of the clutch worm wheel (3e) tend to slide out of engagement with the fourth gear teeth (40) of the ratchet wheel. The cam shaft (9) drives the worm wheel (3b) upon displacement of the push rod up to a point where the brake liners (5) contact the brake drum (8) when the brake pedal (15) is actuated. If the force pushing the ratchet wheel is sufficiently high or in case of slackness of the adjuster (3) which may occur due to wear of the brake liners (5), the clutch worm wheel (3e) skips forward by a tooth corresponding to a gear pitch of the clutch worm wheel (3e) to adjust the slackness. Further, during the brake release, as the pinion gear (3f) rotates in the brake release direction, the ratchet wheel rotates the clutch worm wheel (3e) in the brake release direction. Consequently, the worm shaft (3a) is rotationally displaced relative to the worm wheel (3b), such that the worm wheel (3b) comes to rest in a position corresponding to the cam shaft (9) and the brake liners (5) being closer to the brake drum (8), i.e., in a position which reduces the gap (a). In an embodiment, a manual slack adjuster without the clutch worm wheel (3e) and pinion gear (3f) may also be used to adjust the gap (a).
Referring back to figures 1 and 4 , the adjuster (3) is coupled with an actuator (4). The actuator (4) is in contact with the worm shaft (3a) of the adjuster (3). In an embodiment, the actuator (4) may be of an electric motor, hydraulic or mechanical actuators. The actuator (4) is operable by the control unit (10). Further, the plurality of sensors (7) are mounted on the push rod (2) and are in communication with the control unit (10). The plurality of sensors (7) are configured to detect the values of linear displacement of the push rod (2) with respect to time. The push rod (2) is actuated by the brake chamber (1) upon pressing the brake pedal (15) by the user. In an embodiment, the plurality of sensors (7) may be mounted on the adjuster (3) to detect angular displacement of the adjuster (3). In an embodiment, the plurality of sensors (7) may be

mounted on the cam shaft (9) to measure angle of rotation of cam shaft (9) upon actuation of the brake pedal (15). The plurality of sensors (7) sends signals corresponding to the displacement of the pushrod (2) at various time intervals. The control unit (10) receives the signals from the plurality of sensors (7) and determines the displacement of the push rod (2). The control unit also determines a slope of displacement of the pushrod (2) which is the change in displacement of the push rod (2) with respect to time. The travel and time stamp at which a change in slope of displacement has taken place is recorded by the control unit (10). The control unit (10) determines the gap (a) between the brake liners (5) and the brake drum (8) based on the change in slope of displacement of the push rod (2) and the travel and time stamp at which the change in slope has taken place. If the determined gap (a) is more than a predefined value, the control unit (10) sends an actuation signal to the actuator (4) to adjust the gap (a). The actuator (4) comprises a gear unit (not shown in figures) which is coupled to rotate the worm shaft (3a) of the adjuster (3) to advance the worm wheel (3b) by required threads or gears. Alternatively, if the determined gap (a) falls below the pre-set value, the control unit (10) accordingly send an actuation signal to de-adjust or decrease the gap between the brake liners (5) and the brake drum (8). In an embodiment, the control unit (10) considers the angular displacement and rotation angle of the cam shaft (9). In an embodiment, the control unit (10) determines the gap (a) based on the angular displacement of the adjuster unit and the rotation of the cam shaft (9).
In an embodiment, the control unit (10) includes a memory to store the values detected by the plurality of sensors (7). A set of predefined values corresponding to the displacement of the push rod (2) and a gap (a) at that point of displacement for a known braking system is programmed into the control unit (10). In an embodiment, the predefined values may also correspond to the angular displacement of the adjuster (3) and the rotational angle of the cam shaft (9). The set of predefined values include an upper limit, a lower limit of the gap (a) and a predefined gap (a) to be maintained between the brake liners (5) and the brake drum (8). The control unit (10) is configured to compare the determined change in slope of displacement values stored in the data library with the set of predefined values to determine the gap (a). If the determined gap (a) crosses the upper limit, the control unit (10) sends the actuation signal to the actuator (4) to rotate the gear unit in a direction towards reducing the gap (a) by rotating the worm shaft (3a) of the adjuster (3). Alternatively, if the determined gap (a) is closer to the lower limit, the control unit (10) sends the actuation signal to the actuator (4) to rotate the gear unit in a direction towards increasing the gap (a). In an embodiment, the linear displacement

of the push rod (2) is in the range of 0 to 65 mm, angular displacement of the adjuster (3) and rotational angle of the cam shaft (9) are in the range of 0 – 90°. However, this cannot be considered as a limitation and the values can be varied based on the configuration of the braking system.
The control unit (10) is also communicatively coupled to an accelerator pedal, a parking brake sensor, a brake sensor, air pressure sensors and to an electromagnetic retarder (not shown) equipped in the vehicle. The electromagnetic retarder (EMR) is connected to the propeller shaft to apply braking torque on the propeller shaft to reduce the speed of the transmission output shaft of the vehicle. The actuation signal for the adjustment of the gap (a) is given by the control unit (10) only when the vehicle speed (20) is in the range of 0-5 kmph. Further, the control unit (10) also receives the status of the parking brake (22) of the vehicle in an engaged or disengaged condition. In an embodiment, the status is received in form of a signal by a sensor associated with the parking brake (22) of the vehicle. The control unit (10) detects when the EMR is in operation (28), and sends an actuation signal to increase the gap (a) between the brake liners (5) and the brake drum (8). In an embodiment, the control unit (10) receives signals from the air pressure sensors (27) to determine the pressure drop in a brake line and generates an actuation signal to reduce the gap (a) for better contact of the brake liners (5) with the brake drum (8) to support the braking of the vehicle.
The present disclosure also discloses a method (200) of adjusting a braking system as shown in Figure 6. The method (200) comprises determining displacement values of a push rod (2) continuously at step 101. Further, the slope of displacement of the push rod (2) is determined by the control unit (10) and a change in slope of displacement of the push rod (2) at step 102. Later, the travel and time stamp of the change in slope of displacement of the push rod (2) is recorded at step 103. At step 104, the gap between the brake liner (5) and the brake drum (8) is determined by the control unit (10) based on the calculated change in slope of displacement of push rod (2) and its corresponding travel and time stamp values. Lastly, the gap (a) is selectively adjusted if the determined gap (a) is more than the predefined gap (a) at step 105.
Referring back to figure 7, a flow diagram of a method of adjusting a braking system is disclosed. The method incudes the aspects of determining the displacement of the push rod (2). The displacement of the push rod (2) is determined by the plurality of sensors (7) associated with the push rod (2). The plurality of sensors (7) provide signal to the control unit (10) corresponding to the displacement of the push rod (2) with respect to time. The control unit

(10) receives a plurality of signals from a sensor (not shown) that determines speed of the vehicle and the sensor associated with the electromagnetic retarder (EMR) of a vehicle. In an embodiment, the control unit (10) may receive signals directly from the respective sensors or through a transmission module associated with the control unit (10). Based on the parameters of the received signals, the control unit (10) determines the slope of displacement of the push rod (2) and the change in slope value. The control unit (10) determines a travel and time stamp at which the change in slope of displacement of the push rod (2) has taken place. Based on the determined change in slope of displacement values of the push rod (2) and the travel and time stamp, the control unit (10) determines the gap (a) between the brake liners (5) from the inner surface of the brake drum (8). If the determined gap (a) is more than the predefined value recorded in the control unit (10), the control unit (10) proceeds to the next step to check the status of EMR operation. If the EMR mode (28) is in operation the control unit (10) proceeds to the next step and determines the speed of the vehicle based on the signals received by the plurality of sensors (7). If the vehicle speed (20) is found to be less than 5kmph, the control unit (10) determines the status of the parking brake (22) in engaged or in disengaged position. If all the three conditions such as the EMR operation/mode (28), vehicle speed (20) and the parking brake status (22) are satisfied, the control unit (10) sends an actuation signal to the actuator (4) to adjust the gap (a) between the brake liner (5) and the brake drum (8). Similarly, if the determined gap (a) is less than the pre-set value, the control unit (10) checks for all the three conditions of the EMR mode (28), vehicle speed and the parking brake status and de-adjusts the gap (a) if all the conditions are satisfied. Alternatively, if any one of the three aforementioned conditions are not satisfied, the control unit (10) takes no action and the brake system is operated without adjusting the gap (a).
In an embodiment, the control unit (10) sends an actuation signal to the adjuster (3) to the gap (a) when the EMR is in operation and the speed of the vehicle is in the range of 0-5 kmph.
In an embodiment, the control unit (10) continuously monitors the displacement of the push rod (2), angular displacement of the adjuster (3), rotation angle of the camshaft (9) and determines the values either independently or in combination to accurately determine the gap (a).

In an embodiment, the control unit (10) also uses pressure value data (27) from the brake lines along with the change in displacement values to improve the accuracy of determination of the gap (a).
In an embodiment, the speed of the vehicle may be in range of 0-10 kmph for adjusting the gap (a). However this cannot be considered as a limitation and the adjustment depends on the control unit (10) and the accuracy in detecting the values of change in slope of the push rod, adjuster and the camshaft at various speeds of the vehicle.
In an embodiment, the control unit (10) receives signal from a sensor associated with EMR and sends an actuation signal .to the adjuster to increase the gap (a) between the brake liners (5) and the brake drum (8) for effective usage of EMR for braking of the vehicle.
In an embodiment, the increase in gap (a) during EMR mode (28) enables full utilization of EMR braking, thus improving the life of brake liners (5) and offers effective braking of the vehicle.
In an embodiment, the actuator of the actuator (4) may be a servo motor, electrical motor or connected to the adjuster to provide automated movement of the worm shaft (3a) without affecting the worm wheel (3b) position to automatically adjust the gap (a).
In an embodiment, the system (100) and the method may be easily employed in heavy and light duty vehicles for effective braking.
In an embodiment, the system (100) may be economical to manufacture, as the actuator (4) may be installed to the existing (auto or manual) adjuster (3), leading to less complexity and a simple system.
In an embodiment of the disclosure, the control unit (10) or electronic control unit may be a centralized control unit, or a dedicated control unit associated with the vehicle. The control unit may be implemented by any computing systems that is utilized to implement the features of the present disclosure. The control unit may be comprised of a processing unit. The processing unit may comprise at least one data processor for executing program components for executing user- or system-generated requests. The processing unit may be a specialized processing unit such as integrated system (bus) controllers, memory management control units, floating point units, graphics processing units, digital signal processing units, etc. The processing unit may

include a microprocessor, such as AMD Athlon, Duron or Opteron, ARM’s application, embedded or secure processors, IBM PowerPC, Intel’s Core, Itanium, Xeon, Celeron or other line of processors, etc. The processing unit may be implemented using a mainframe, distributed processor, multi-core, parallel, grid, or other architectures. Some embodiments may utilize embedded technologies like application-specific integrated circuits (ASICs), digital signal processors (DSPs), Field Programmable Gate Arrays (FPGAs), etc.
In some embodiments, the ECU may be disposed in communication with one or more memory devices (e.g., RAM, ROM etc.) via a storage interface. The storage interface may connect to memory devices including, without limitation, memory drives, removable disc drives, etc., employing connection protocols such as serial advanced technology attachment (SATA), integrated drive electronics (IDE), IEEE-1394, universal serial bus (USB), fiber channel, small computing system interface (SCSI), etc. The memory drives may further include a drum, magnetic disc drive, magneto-optical drive, optical drive, redundant array of independent discs (RAID), solid-state memory devices, solid-state drives, etc.
It is to be understood that a person of ordinary skill in the art may develop a system of similar configuration without deviating from the scope of the present disclosure. Such modifications and variations may be made without departing from the scope of the present invention. Therefore, it is intended that the present disclosure covers such modifications and variations provided they come within the ambit of the appended claims and their equivalents.
Equivalents:
With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity.
It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes but is not limited to,” etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an

intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases “at least one” and “one or more” to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim recitation to inventions containing only one such recitation, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an” (e.g., “a” and/or “an” should typically be interpreted to mean “at least one” or “one or more”); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of “two recitations,” without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to “at least one of A, B, and C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system (108) having at least one of A, B, and C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances, where a convention analogous to “at least one of A, B, or C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system (108) having at least one of A, B, or C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase “A or B” will be understood to include the possibilities of “A” or “B” or “A and B.” 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.
Referral Numerals:

System 100
Method 200
Control unit 10
Brake chamber 1
Push rod 2
Adjuster unit 3
Worm shaft 3a
Worm wheel 3b
Lock plate Assembly 3c
Housing 3d
Clutch worm wheel 3e
Pinion gear 3f
Actuator 4
Brake liners 5
Wheel hub 6
Plurality of sensors 7
Brake drum 8
Cam shaft 9
S-cam 12
Gap a
Brake valve 14
Brake pedal 15
Spring member 16
Diaphragm 18
Vehicle speed status 20
Parking brake status 22
Main brake status 24

Air pressure data 27
EMR mode 28
Gear assembly 30
First gear teeth 32
Second gear teeth 36
Third gear teeth 38
Fourth gear teeth 40

We claim:
1. An automated brake adjustment system (100) for a vehicle comprising:
a brake pedal (15) connected to a brake chamber (1) through a brake valve (14); an adjuster unit (3) coupled to the brake chamber (1) by a push rod (2); a cam shaft (9) connected to the adjuster unit (3) comprises a cam at one end, wherein the cam is defined in a brake drum (8);
an actuator (4) integrated to the adjuster unit (3) wherein the actuator (4) selectively actuates the adjuster unit (3);
a plurality of sensors (7) connected to the pushrod (2), the adjuster unit (3) and the cam shaft (9), wherein the plurality of sensors (7) detects and sends a signal upon actuation of the brake pedal; and
a control unit (10) in communication with the plurality of sensors (7) and the actuator (4), the control unit (10) is configured to:
receive a signal from a plurality of sensors (7) to determine displacement of the push rod (2);
receive a signal from a plurality of sensors to determine slope of displacement of the push rod (2) and a change in slope of displacement of the push rod (2);
record a travel and time stamp at which the change in slope of displacement of the push rod (2) has occurred;
determine a gap (a) between a brake liner (5) and the brake drum (8) based on the determined slope of displacement of the pushrod (2) and the travel and time stamp of the change in slope of displacement; and
wherein the control unit (10) sends an actuation signal to the actuator (4) to selectively adjust the gap (a) if the determined gap is more than a predefined gap and less than the predefined gap.
2. The system (100) as claimed in claim 1, wherein the cam of the cam shaft (9) is configured to be in contact with the brake liner (5) to displace the brake liner (5) within the brake drum (8).
3. The system (100) as claimed in claim 1, wherein the adjuster unit (3) comprises a worm shaft (3a) coupled to a gear assembly of the actuator (4) to adjust the gap (a) upon rotation of the gear assembly.

4. The system (100) as claimed in claim 1, wherein the control unit receives the signal from the plurality of sensors (7) corresponding to a linear displacement of the push rod (2), an angular displacement of the adjuster (3) and a rotation angle of the cam shaft (9) upon actuation of the brake pedal (15).
5. The system (100) as claimed in claim 1, wherein the change in displacement of the push rod (2) and the adjuster (3) is proportional to an increase in the brake pedal (15) movement during braking.
6. The system (100) as claimed in claim 1, wherein the control unit (10) determines the gap (a) based on change of slope of angular displacement of the adjuster (3).
7. The system (100) as claimed in claim 1, wherein the control unit (10) determines the gap (a) based on change of rotational angle of the cam shaft (9).
8. The system (100) as claimed in claim 1, wherein the control unit (10) compares one or more values of the change in slope of displacement of the push rod (2) with a set of predefined values to determine the gap (a) and operates the actuator to selectively adjust the gap (a) if the determined gap deviates from the set of predefined values.
9. The system (100) as claimed in claim 1, wherein, the set of predefined values correspond to a displacement of the push rod when the brake liners (5) come into contact with the brake drum (8) with respect to time.
10. The system (100) as claimed in claim 1, wherein the linear displacement of the push rod (2) is in the range of 0 to 65 mm, angular displacement of the adjuster (3) and rotational angle of the cam shaft (9) are in the range of 0 to 90°.
11. The system (100) as claimed in claim 1, wherein the adjuster unit is actuated by the actuator to adjust the gap (a) between the brake liner (5) and the brake drum (8) when the vehicle speed is less than 5 kmph and when the brakes are in disengaged condition.
12. The system (100) as claimed in claim 1, wherein the plurality of sensors (7) is at least one of linear variable differential transducer (LVDT), linear potentiometer, angle sensor and rotary encoder.

13. The system (100) as claimed in claim 1, wherein the control unit (10) receives a signal from an electromagnetic retarder equipped on a propeller shaft of the vehicle from a sensor, the control unit (10) generates an actuation signal to the adjuster unit (3) to increase the gap (a) during an operation of the electromagnetic retarder.
14. A method (200) for automatically adjusting a braking system, the method (200) comprising;
receiving, by a control unit (10), a signal from a plurality of sensors associated with the push rod (2) to determine displacement of a push rod (2), the push rod (2) is coupled to an adjuster unit (3) which is connected to a brake drum (8);
determine, by a control unit (10), a slope of displacement of the push rod (2) and a change in slope of displacement of the push rod (2);
recording, by a control unit (10), the travel and time stamp at which a change in displacement of the push rod (2) has occurred (1);
determining, by a control unit (10), a gap (a) between a brake liner (5) and the brake drum (8) based on the determined change in slope of displacement of the pushrod (2), travel and time stamp of the change in displacement of the push rod (2); and
wherein the control unit (10) sends an actuation signal to the actuator (4) to selectively adjust the gap (a) if the determined gap is more than a predefined gap and less than the predefined gap.