AU2019272061A1

AU2019272061A1 - Braking system for machine

Info

Publication number: AU2019272061A1
Application number: AU2019272061A
Authority: AU
Inventors: Alexander Eli Dowling
Original assignee: Caterpillar Underground Mining Pty Ltd
Current assignee: Caterpillar Underground Mining Pty Ltd
Priority date: 2019-11-29
Filing date: 2019-11-29
Publication date: 2021-06-17
Also published as: ZA202006769B

Abstract

of the Disclosure BRAKING SYSTEM FOR MACHINE A braking system for a machine includes a source of hydraulic fluid and a first valve assembly in fluid communication with the source. The braking system further includes an electro-hydraulic brake booster device. The electro-hydraulic brake booster device includes a second valve assembly in fluid communication with the source and a control module communicably coupled with the second valve assembly. The control module is configured to transmit control signals to the second valve assembly for operating the second valve assembly. The braking system includes at least one brake assembly that is actuated based on fluid pressure received from the source via both the first valve assembly and the second valve assembly. The first valve assembly and the second valve assembly are connected in parallel between the source and each of the at least one brake assembly by selective fluid communication. 214 (Zo C.1.1) CO CID CO C"2 Sq CNZ CO co t- rl CO CIQ C,2 LO C\? C\2 CIQ tl- o'2 co C\2 r o co zl- cc - CD C'Q C\? co C', CV Co C.,2 -q CZ) CV ck2 ck2 C1.2 CO co co t* 4zo tl- o'2 cv -,rQ- CV CV -- ro c I, CV CV CV tCV oo CV CV CV CV 00 C\2 co C\2 ZO C C\2 Cv C\2 NOW V CO CV\ , ) rZo CV CV Cv CNZ CO FT CO CV CV LO CV CV CO Lo CO CO CV ,Izq. 012 CV C\2 A\ IRr CV C\.Z 0,2 cl 2 cq .J C\2 CO NZ C,2 CAD C112 Lo C\2 C\2 C,,,2 C'2 C112 CID C112 114- CN2 C112 co CvD C\2 C\2 114- ------------- t C: CO cc CO C\2 C\2 C 2 C,2 C112 CIQ C\2 C\2 CZ) co 012 C112

Description

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BRAKING SYSTEM FOR MACHINE

Technical Field

[0001] The present disclosure relates to a braking system. More particularly, the present disclosure relates to the braking system for machines, such as those used at mining or construction sites.

Background

[0002] Machines, such as those operating at mining worksites, typically include a braking system that is used to slow a speed of the machines or halt the machines, as per requirements. Such braking systems are typically mechanically operated systems. More particularly, the braking systems are actuated based on opening of a brake pedal valve that is mechanically linked with the brake pedal. As per current machine compliance regulations, it is desirable that the braking system provides a quicker brake response timing to allow deceleration or halting of the machine within a certain distance as well as time limit. However, increasingly stringent compliance regulations demand advanced braking systems that exhibit improved performance as compared to conventional braking systems.

[0003] U.S. Patent Number 8,870,300 describes a method for actuating a hydraulic vehicle brake system. The method includes a master brake cylinder with a preferably electromechanical brake booster and a wheel slip control device. The master brake cylinder is actuated simultaneously with the brake booster, and hydraulic pumps of the wheel slip control device are driven by an electric motor. Pressure builds more quickly in the wheel brakes of the vehicle brake system for safety and assistance functions that require high pressure build-up dynamic. The method also increases the wheel brake pressure using the pressure that can be generated by actuating the master brake cylinder with the brake booster.

[0004] Reference to any prior art in the specification is not an acknowledgement or suggestion that this prior art forms part of the common general knowledge in any jurisdiction or that this prior art could reasonably be expected to be combined with any other piece of prior art by a skilled person in the art.

[0005] By way of clarification and for avoidance of doubt, as used herein and except where the context requires otherwise, the term "comprise" and variations of the term, such as "comprising", "comprises" and "comprised", are not intended to exclude further additions, components, integers or steps.

Summary of the Disclosure

[0006] In an aspect, the present invention provides a braking system for a machine. The machine includes a brake pedal. Further, the braking system includes a source of hydraulic fluid. The braking system also includes a first valve assembly in fluid communication with the source. An operation of the first valve assembly is based on a movement of the brake pedal. The braking system further includes an electro-hydraulic brake booster device that is operable based on the movement of the brake pedal. The electro-hydraulic brake booster device includes a second valve assembly in fluid communication with the source. The electro hydraulic brake booster device also includes a control module communicably coupled with the second valve assembly. The control module is configured to transmit control signals to the second valve assembly for operating the second valve assembly based on the movement of the brake pedal. The braking system includes at least one brake assembly. The first valve assembly and the second valve assembly are connected in parallel between the source and each of the at least one brake assembly by selective fluid communication. Further, the at least one brake assembly is actuated based on fluid pressure received from the source via both the first valve assembly and the second valve assembly.

[0007] In another aspect, the present invention provides a machine. The machine includes a machine frame. The machine also includes a plurality of axles supported on the machine frame. Each of the plurality of axles support a pair of wheels. The machine further includes a brake pedal movable by an operator of the machine. The machine includes a braking system adapted to initiate at least one of a halting and deceleration of the machine based on a movement of the brake pedal. The braking system includes a source of hydraulic fluid. The braking system also includes a first valve assembly in fluid communication with the source. An operation of the first valve assembly is based on a movement of the brake pedal.

The braking system further includes an electro-hydraulic brake booster device that is operable based on the movement of the brake pedal. The electro-hydraulic brake booster device includes a second valve assembly in fluid communication with the source. The electro-hydraulic brake booster device also includes a control module communicably coupled with the second valve assembly. The control module is configured to transmit control signals to the second valve assembly for operating the second valve assembly based on the movement of the brake pedal. The braking system includes at least one brake assembly. The first valve assembly and the second valve assembly being connected in parallel between the source and each of the at least one brake assembly by selective fluid communication. Further, the at least one brake assembly is actuated based on fluid pressure received from the source via both the first valve assembly and the second valve assembly.

[0008] Other features and aspects of this disclosure will be apparent from the following description and the accompanying drawings.

Brief Description of the Drawings

[0009] FIG. 1 is a perspective view of a machine, according to one embodiment of the present disclosure;

[0010] FIG. 2 is a schematic representation of a braking system associated with the machine shown in FIG. 1, according to one embodiment of the present disclosure;

[0011] FIG. 3 is a block diagram illustrating the braking system shown in FIG. 2; and

[0012] FIG. 4 is a block diagram illustrating an electro-hydraulic brake booster device associated with the braking system shown in FIG. 2.

Detailed Description

[0013] Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.

[0014] FIG. 1 illustrates a perspective view of a machine 100, according to an exemplary embodiment of the present disclosure. The machine 100 is embodied as a manually operated machine. However, the machine 100 may be embodied as an autonomous or semi-autonomous machine, without any limitations. In the illustrated embodiment, the machine 100 is an underground articulated truck. In alternative embodiments, the machine 100 may include a mining truck, an excavator, a dozer, a harvester, a backhoe, or other types of machines known in the art. Further, the machine 100 may operate at a worksite such as a mine site, a landfill, a quarry, a construction site, or any other type of worksite. The machine 100 may perform one or more than one type of operation associated with an industry such as mining, construction, farming, transportation, or any other industry known in the art.

[0015] The machine 100 includes a machine frame 102. The machine frame 102 supports one or more components of the machine 100. The machine 100 includes an enclosure 104 provided on the machine frame 102. The enclosure 104 encloses a power source (not shown) that is mounted on the machine frame 102. The power source may provide power to the machine 100 for mobility and operational requirements. The power source may be any power source, such as an internal combustion engine, batteries, motor, and so on, or a combination thereof. The internal combustion engine may include a diesel engine, a gasoline engine, a gaseous fuel-powered engine, or any other combustion engine.

[0016] Further, the machine 100 also includes a number of axles 106, 108 supported on the machine frame 102. In the illustrated example, the machine 100 include two axles, namely the front axle 106 and the rear axle 108. Further, each of the number of axles 106, 108 support a pair of wheels 110, 112. More particularly, the front axle 106 supports the pair of front wheels 110, whereas the rear axle 108 supports the pair of rear wheels 112. The wheels 110, 112 rotate about their respective axes thereby propelling the machine 100 on the worksite. Alternatively, when the machine 100 is embodied as another type of machine, such as a tractor, it can be contemplated to embody the wheels 110, 112 in the form of tracks (not shown) such that the tracks propel the machine 100.

[0017] The machine 100 also includes an operator cabin 114 mounted on the machine frame 102. An operator of the machine 100 is seated within the operator cabin 114 to perform one or more machine operations. The operator cabin 114 houses one or more devices (not shown) of the machine 100, such as a display unit, a touchscreen unit, a steering, an operator console, switches, levers, knobs, buttons, and so on. These controls may assist the operator in operating the machine 100. Further, the machine 100 includes a brake pedal 116 (shown in FIG. 3) movable by an operator of the machine 100. The brake pedal 116 is disposed in the operator cabin 114. When the operator of the machine 100 depresses the brake pedal 116, a braking system 200 (shown in FIG. 2) of the machine 100 causes the wheels 110, 112 of the machine 100 to slow down or come to a halt, thereby decelerating the machine 100 or halting the machine 100.

[0018] In an example, a sensor 118 (shown in FIGS. 3 and 4) may be associated with the brake pedal 116 for acquisition of the operator's braking demand. The sensor 118 may be embodied as a rotary sensor. The sensor 118 may generate a signal corresponding to a distance by which the brake pedal 116 moves when the brake pedal 116 is depressed by the operator. In another example, the sensor 118 may generate a signal that corresponds to a pressure applied by the operator on the brake pedal 116. Further, the machine 100 also includes a park lever (not shown) disposed in the operator cabin 114. The park lever may be used to actuate park brakes of the machine 100.

[0019] The machine 100 further includes a load carrier 120 for carrying material for transportation purposes. The load carrier 120 is coupled with the machine frame 102, and may be tilted between a lowered position, as shown, and a lifted position, to dump material from the load carrier 120 in a conventional manner. Additionally, the machine 100 may include components and/or systems (not shown), such as a fuel delivery system, an air delivery system, a lubrication system, a propulsion system, a drivetrain, a drive control system, a machine control system, a ballast system, and so on, based on application requirements.

[0020] As shown in FIG. 2, the machine 100 also includes the braking system 200. The braking system 200 initiates a halting or deceleration of the machine 100 based on a movement of the brake pedal 116 (see FIG. 3). In the illustrated example, the braking system 200 controls each of the front wheels 110 (see FIG. 1) and the rear wheels 112 (see FIG. 1) of the machine 100 in order to halt or decelerate the machine 100. Alternatively, the braking system 200 may control only the front wheels 110 in order to halt or decelerate the machine 100, as per requirements.

[0021] The braking system 200 includes a source 202, 204 of hydraulic fluid. More particularly, the braking system 200 includes the first source 202 of hydraulic fluid and the second source 204 of hydraulic fluid. Alternatively, the braking system 200 may include a single source of hydraulic fluid. The hydraulic fluid may include oil. Further, the source 202, 204 may include a variable volume fluid reservoir for containing hydraulic fluid which is maintained at a slightly elevated pressure. In the illustrated example, the source 202, 204 includes an accumulator for storing hydraulic fluid under pressure. The accumulator may embody a bladder type accumulator, a piston actuated accumulator, or a diaphragm actuated accumulator.

[0022] The braking system 200 includes a hydraulic tank 206 (shown in FIG. 3) in selective fluid communication with cylinders 274 of a corresponding brake assembly 208, 210. The hydraulic tank 206 receives hydraulic fluid from the cylinders 274, via a first valve assembly 212. More particularly, hydraulic fluid drains from the cylinders 274 into the hydraulic tank 206 when the brake pedal 116 is released. The hydraulic tank 206 includes a reservoir or tank that is generally known in the art for receiving hydraulic fluid from the cylinders 274 and delivering hydraulic fluid to the first and second sources 202, 204. A pump (not shown) may be used to pressurize hydraulic fluid and deliver hydraulic fluid from the hydraulic tank 206 to the first and second sources 202, 204 via fluid lines 282, 284, respectively.

[0023] The braking system 200 includes the first valve assembly 212 in fluid communication with the source 202, 204. The first valve assembly 212 is a mechanically actuated valve assembly. The first valve assembly 212 may be mechanically connected to the brake pedal 116. More particularly, the first valve assembly 212 includes a first valve 214 and a second valve 216, such that the first and second valves 214, 216 are embodied as brake pedal valves that are mechanically linked to the brake pedal 116. In an example, each of the first and second valves 214, 216 may be embodied as a directional valve, without any limitations. Further, the first and second valves 214, 216 are in fluid communication with the first and second sources 202, 204, respectively, the hydraulic tank 206, and the brake assembly 208, 210. The first valve 214 is in fluid communication with the first source 202 via a fluid line 218. Further, the second valve 216 is in fluid communication with the second source 204 via a fluid line 220.

[0024] An operation of the first valve assembly 212 is based on the movement of the brake pedal 116. More particularly, the depression of the brake pedal 116 causes the first and second valves 214, 216 to open. When the first and second valves 214, 216 open, hydraulic fluid from the first and second sources 202, 204 is directed towards the brake assembly 208, 210, respectively. Further, the release of the brake pedal 116 causes the first and second valves 214, 216 to close. When the first and second valves 214, 216 close, the first and second valves 214, 216 restrict a flow of hydraulic fluid towards the brake assembly 208, 210, via the first valve assembly 212.

[0025] The braking system 200 includes an electro-hydraulic brake booster device 222 that is operable based on the movement of the brake pedal 116. The electro-hydraulic brake booster device 222 includes a second valve assembly 224 in fluid communication with the source 202, 204. The first valve assembly 212 and the second valve assembly 224 are connected in parallel between the source 202, 204 and the brake assembly 208, 210 by selective fluid communication.

[0026] An operation of the second valve assembly 224 is based on the movement of the brake pedal 116. The second valve assembly 224 is embodied as an electro-hydraulic valve assembly. The second valve assembly 224 includes one or more solenoid operated valves 226, 228, 230, 232. The second valve assembly 224 includes one or more on/off valves 226, 228. More particularly, the second valve assembly 224 includes the first on/off valve 226 and the second on/off valve 228. In an example, each of the first and second on/off valves 226, 228 may be embodied as a 2/2 way valve, without any limitations. A control module 234 (shown in FIG. 3) controls an operation of the on/off valves 226, 228 based on the movement of the brake pedal 116. The first and second on/off valves 226, 228 open and close based on signals received from the control module 234. The first on/off valve 226 is in fluid communication with the first source 202 via a fluid line

236. Further, the second on/off valve 228 is in fluid communication with the second source 204 via a fluid line 238.

[0027] Further, the second valve assembly 224 includes one or more proportional pressure control valves 230, 232. More particularly, the second valve assembly 224 includes the first proportional pressure control valve 230 and the second proportional pressure control valve 232. In an example, each of the first and second proportional pressure control valves 230, 232 may be embodied as a directional valve, without any limitations. The first proportional pressure control valve 230 is in fluid communication with the first on/off valve 226 via a fluid line 240. Further, the second proportional pressure control valve 232 is in fluid communication with the second on/off valve 228 via a fluid line 242.

[0028] The control module 234 controls an operation of the proportional pressure control valves 230, 232 based on a distance of the movement of the brake pedal 116. More particularly, a degree of opening of the first and second proportional pressure control valves 230, 232 is based on the distance of the movement of the brake pedal 116. For example, the first and second proportional pressure control valves 230, 232 may open fully if the brake pedal 116 is fully depressed, or the first and second proportional pressure control valves 230, 232 may partially open if the brake pedal 116 is slightly depressed or if the brake pedal 116 is depressed half-way. In one example, the second valve assembly 224 may omit the on/off valves 226, 228 and only include the proportional pressure control valves 230, 232.

[0029] As shown in FIG. 4, the depression of the brake pedal 116 causes the on/off valves 226, 228 and the proportional pressure control valves 230, 232 to open. When the on/offvalves 226, 228 and the proportional pressure control valves 230, 232 open, hydraulic fluid from the first and second sources 202, 204 is directed towards the brake assembly 208, 210, respectively. Further, the release of the brake pedal 116 causes the on/off valves 226, 228 and the proportional pressure control valves 230, 232 to close. When the on/off valves 226, 228 and the proportional pressure control valves 230, 232 close, a flow of hydraulic fluid towards the brake assembly 208, 210, via the second valve assembly 224, is restricted.

[0030] The electro-hydraulic brake booster device 222 also includes the control module 234. The control module 234 is communicably coupled with the second valve assembly 224. The control module 234 transmits control signals to the second valve assembly 224 for operating the second valve assembly 224 based on the movement of the brake pedal 116. More particularly, the control module 234 is communicably coupled with the sensor 118. Based on signals received from the sensor 118, the control module 234 generates the control signals to open or close the on/off valves 226, 228 and the proportional pressure control valves 230, 232. More particularly, when the brake pedal 116 is depressed, the sensor 118 generates the signal indicating the depression of the brake pedal 116 that is received by the control module 234. The control module 234 in turn generates the control signal to open the on/off valves 226, 228. Further, the control module 234 also generates the control signal to open the proportional pressure control valves 230, 232 based on the distance of the movement of the brake pedal 116.

[0031] In some examples, the control module 234 may receive a Pulse Width Modulation (PWM) signal from the sensor 118. The control module 234 interprets this PWM signal to determine a percentage "P" by which the proportional pressure control valves 230, 232 needs to be opened. If the percentage "P" is greater than a predefined value "Xl", the control module 234 generates and transmits the control signal to open the on/off valves 226, 228. The predefined value "X1" may be stored in a memory of the control module 234. The predefined value "X1" may be defined as a threshold value such that when the percentage "P" is greater than the predefined value "X1", the control module 234 causes opening of the second valve assembly 224. Further, based on the percentage "P", the control module 234 generates another control signal to control the degree of opening of the proportional pressure control valves 230, 232. It should be noted that the percentage "P" is based on the distance travelled by the brake pedal 116. In another example, the percentage "P" may be based on the amount of pressure applied on the brake pedal 116, without any limitations. Moreover, when the brake pedal 116 is released, the sensor 118 generates a signal indicating the release of the brake pedal 116 that is received by the control module 234. The control module 234 in turn generates the control signals to close the on/off valves 226, 228 and the proportional pressure control valves 230, 232.

[0032] Referring now to FIG. 2, the braking system 200 includes a pair of shuttle valves 244, 246. More particularly, the braking system 200 includes the first shuttle valve 244 and the second shuttle valve 246. The first shuttle valve 244 is in fluid communication with the first valve 214 via a fluid line 248 and the first proportional control valve 230 via a fluid line 250. The second shuttle valve 246 is in fluid communication with the second valve 216 via a fluid line 252 and the second proportional control valve 232 via a fluid line 254. Further, the first and second shuttle valves 244, 246 are in fluid communication with the cylinders 274 of the corresponding brake assembly 208, 210, via fluid lines 256, 258.

[0033] When the brake pedal 116 (see FIG. 3) is depressed, the first on/off valve 226 and the first proportional pressure control valve 230 open so that hydraulic fluid from the first source 202 is directed towards the first shuttle valve 244 via the fluid lines 236, 240, 250. The first shuttle valve 244 may in turn direct hydraulic fluid towards the brake assembly 208 via the fluid line 256. Further, the depression of the brake pedal 116 causes the first valve 214 to open so that hydraulic fluid from the first source 202 is directed towards the first shuttle valve 244 via the fluid lines 218, 248. The first shuttle valve 244 may in turn directs hydraulic fluid towards the brake assembly 208 via the fluid line 256.

[0034] It should be noted that the first shuttle valve 244 receives hydraulic fluid flow via both the first proportional pressure control valve 230 and the first valve 214. However, the first shuttle valve 244 directs hydraulic fluid that is at a higher pressure towards the brake assembly 208. When the brake pedal 116 is depressed, the first shuttle valve 244 initially receives hydraulic fluid at high pressure from the first on/off valve 226 and the first proportional control valve 230. This high pressure hydraulic fluid is then directed towards the brake assembly 208 to start filling the cylinder 274 of a service brake actuator 266 in order to pressurize a brake pack 264. Meanwhile, the first shuttle valve 244 also receives high pressure hydraulic fluid through the first valve 214. At this stage, the pressure of hydraulic fluid received from the first valve 214 is greater than the pressure of hydraulic fluid received from the first on/offvalve 226 and the first proportional control valve 230.

Thus, the first shuttle valve 244 allows passage of hydraulic fluid received from the first valve 214 to continue pressurizing the brake pack 264.

[0035] Similarly, the depression of the brake pedal 116 causes the second on/off valve 228 and the second proportional pressure control valve 232 to open so that hydraulic fluid from the second source 204 is directed towards the second shuttle valve 246 via the fluid lines 238, 242, 254. The second shuttle valve 246 may in turn directs hydraulic fluid towards the brake assembly 208, 210 via the fluid line 258. Further, the depression of the brake pedal 116 causes the second valve 216 to open so that hydraulic fluid from the second source 204 is directed towards the second shuttle valve 246 via the fluid lines 220, 252. The second shuttle valve 246 may in turn direct hydraulic fluid towards the brake assembly 208, 210 via the fluid line 258.

[0036] It should be noted that the second shuttle valve 246 receives hydraulic fluid flow via both the second proportional pressure control valve 232 and the second valve 214. However, the second shuttle valve 246 directs hydraulic fluid that is at a higher pressure towards the brake assembly 210. When the brake pedal 116 is depressed, the second shuttle valve 246 initially receives hydraulic fluid at high pressure from the second on/off valve 228 and the second proportional control valve 232. This high pressure hydraulic fluid is then directed towards the brake assembly 210 to start filling the cylinder 274 of a service brake actuator 266 in order to pressurize a brake pack 264. Meanwhile, the second shuttle valve 246 also receives high pressure hydraulic fluid through the second valve 216. At this stage, the pressure of hydraulic fluid received from the second valve 216 is greater than the pressure of hydraulic fluid received from the second on/off valve 228 and the second proportional control valve 232. Thus, the second shuttle valve 246 allows passage of hydraulic fluid received from the second valve 216 to continue pressurizing the brake pack 264. In the illustrated example, the fluid lines 256, 258 include a pressure sensor 260, 262 to sense a pressure of hydraulic fluid flowing through the fluid lines 256, 258.

[0037] Further, the braking system 200 includes the brake assembly 208, 210. The brake assembly 208, 210 may be associated with the pair of front wheels 110 (see FIG. 1) and/or the pair of rear wheels 112 (see FIG. 1) of the machine 100. In the illustrated example, the braking system 200 includes a pair of brake assemblies 208 associated with the front wheels 110 and a pair of brake assemblies 210 associated with the rear wheels 112.

[0038] The brake assembly 208, 210 is in selective fluid communication with the first and second sources 202, 204 and receives hydraulic fluid from the first and second sources 202, 204, respectively. The brake assembly 208, 210 is actuated based on fluid pressure received from the source 202, 204 via both the first valve assembly 212 and the second valve assembly 224. More particularly, as each of the first and second valve assemblies 212, 224 are disposed parallelly between the first and second sources 202, 204 and the brake assembly 208, 210, the brake assembly 208, 210 receives hydraulic fluid from each of the first and second sources 202, 204, respectively.

[0039] Each brake assembly 208, 210 includes the brake pack 264 disposed within a chamber (not shown), the service brake actuator 266, and a park brake actuator 268. The brake pack 264 may include a drum brake pack or a disc brake pack. The service brake actuator 266 is provided to actuate service brakes of the machine 100, whereas the park brake actuator 268 is provided to actuate park brakes of the machine 100. Each of the service and park brake actuators 266, 268 include a piston 270, 272, a cylinder 274, 276, and a biasing member 278, 280. The pistons 270, 272 are operably connected to the brake pack 264. When the brake pedal 116 is depressed, hydraulic fluid from the first and second sources 202, 204 is received within the respective cylinders 274 of the service brake actuator 266. Further, hydraulic fluid received within the cylinders 274 impinges on the corresponding pistons 270 of the service brake actuator 266. The hydraulic fluid applies a force on the pistons 270 against a biasing force of the corresponding biasing members 278. The force applied on the pistons 270 effects hydraulic actuation of the service brake actuator 266. The service brake actuator 266 in turn actuates the brake packs 264 thereby causing deceleration or halting of the machine 100.

[0040] Further, when the brake pedal 116 is released, hydraulic fluid flow from the sources 202, 204 is restricted. Moreover, hydraulic fluid starts returning towards the hydraulic tank 206 via the first valve assembly 212 and the second valve assembly 224, thereby causing the pistons 270 of the respective service brake actuators 266 to retract. It should be noted that the first valve assembly 212 and the second valve assembly 224 are in communication with the hydraulic tank 206 via fluid lines 288, 286 respectively, so that the hydraulic fluid can drain to the hydraulic tank 206.

[0041] When the park lever is operated to release the park brakes, hydraulic fluid is directed towards the cylinders 276 of the respective park brake actuators 268 causing an increase in pressure on the respective pistons 272. Thus, hydraulic fluid applies a force on the pistons 272 against a biasing force of the corresponding biasing members 280. The force applied on the pistons 272 causes the brake pack 264 to disengage thereby allowing movement of the machine 100. It should be noted that an architecture of the braking system 200 described herein is exemplary in nature, and the braking system 200 may include additional or fewer components that are arranged in a different configuration to fulfill the function of the braking system 200.

[0042] The control module 234 may embody a single microprocessor or multiple microprocessors for receiving signals from various components of the machine 100. Numerous commercially available microprocessors may be configured to perform the functions of the control module 234. It should be appreciated that the control module 234 may embody a machine microprocessor capable of controlling numerous machine functions. A person of ordinary skill in the art will appreciate that the control module 234 may additionally include other components and may also perform other functions not described herein.

[0043] It is to be understood that individual features shown or described for one embodiment may be combined with individual features shown or described for another embodiment. The above described implementation does not in any way limit the scope of the present disclosure. Therefore, it is to be understood although some features are shown or described to illustrate the use of the present disclosure in the context of functional segments, such features may be omitted from the scope of the present disclosure without departing from the spirit of the present disclosure as defined in the appended claims.

Industrial Applicability

[0044] The braking system 200 provide a simple, effective, and cost-efficient solution for quicker actuation of the brake pack 264 in order to decelerate or halt the machine 100. More particularly, the braking system 200 includes the electro hydraulic brake booster device 222 that provides improved brake response timing by instantly directing hydraulic fluid towards the brake assembly 208, 210 for actuation of the corresponding brake packs 264 when the brake pedal 116 is depressed. Further, as the first and second valve assemblies 212, 224 are arranged in parallel between the source 202, 204 and the brake assembly 208, 210, the service brake actuator 266 receives hydraulic fluid via each of the first and second valve assemblies 212, 224. However, due to the improved brake response timing provided by the incorporation of the electro-hydraulic brake booster device 222, the service brake actuator 266 receives the initial high pressure hydraulic fluid via the second valve assembly 224 followed by receipt of the high pressure hydraulic fluid via the first valve assembly 212.

[0045] As such, the braking system 200 may provide improved automation for the braking system 200 by incorporating an electro-hydraulic braking response in the braking system 200. Further, the braking system 200 described herein ensures adherence to machine compliance regulations as the electro-hydraulic brake booster device 222 allows quicker actuation of the brake packs 264. The braking system 200 employs easily available components on the machine 100, such as the control module 234 and the second valve assembly 224, which in turn reduces complexity and costs. The braking system 200 may be retrofitted on any machine with limited modification to the existing braking system, in turn, providing flexibility and compatibility.

[0046] While aspects of the present disclosure have been particularly shown and described with reference to the embodiments above, it will be understood by those skilled in the art that various additional embodiments may be contemplated by the modification of the disclosed machines, systems and methods without departing from the spirit and scope of the disclosure. Such embodiments should be understood to fall within the scope of the present disclosure as determined based upon the claims and any equivalents thereof.

List of Elements

TITLE: BRAKING SYSTEM FOR MACHINE

FILE: 19-0998-73659

100 Machine

102 Machine Frame

104 Enclosure

106 Front Axle

108 Rear Axle

110 Front Wheels

112 Rear Wheels

114 Operator Cabin

116 Brake Pedal

118 Sensor

120 Load Carrier

200 Braking System

202 First Source

204 Second Source

206 Hydraulic Tank

208 First Brake Assembly

210 Second Brake Assembly

212 First Valve Assembly

214 First Valve

216 Second Valve

218 Fluid Line

220 Fluid Line

222 Electro-Hydraulic Brake Booster Device

224 Second Valve Assembly

226 First On/Off Valve

228 Second On/Off Valve

230 First Proportional Pressure Control Valve

232 Second Proportional Pressure Control Valve

234 Control Module

236 Fluid Line

238 Fluid Line

240 Fluid Line

242 Fluid Line

244 First Shuttle Valve

246 Second Shuttle Valve

248 Fluid Line

250 Fluid Line

252 Fluid Line

254 Fluid Line

256 Fluid Line

258 Fluid Line

260 Pressure Sensor

262 Pressure Sensor

264 Brake pack

266 Service brake actuator

268 Park brake actuator

270 Piston

272 Piston

274 Cylinder

276 Cylinder

278 Biasing Member

280 BiasingMember

282 Fluid Line

284 Fluid Line

286 Fluid Line

288 Fluid Line

Claims

1. A braking system for a machine, wherein the machine includes a brake pedal, the braking system comprising: a source of hydraulic fluid; a first valve assembly in fluid communication with the source, wherein an operation of the first valve assembly is based on a movement of the brake pedal; an electro-hydraulic brake booster device that is operable based on the movement of the brake pedal, the electro-hydraulic brake booster device comprising: a second valve assembly in fluid communication with the source; and a control module communicably coupled with the second valve assembly, wherein the control module is configured to transmit control signals to the second valve assembly for operating the second valve assembly based on the movement of the brake pedal; and at least one brake assembly, the first valve assembly and the second valve assembly being connected in parallel between the source and each of the at least one brake assembly by selective fluid communication, wherein the at least one brake assembly is actuated based on fluid pressure received from the source via both the first valve assembly and the second valve assembly.

2. The braking system of claim 1, wherein the source includes an accumulator for storing hydraulic fluid under pressure.

3. The braking system of claim 1 or 2, wherein the second valve assembly includes at least one solenoid operated valve.

4. The braking system of any one of claims 1 to 3, wherein the second valve assembly includes at least one on/off valve.

5. The braking system of claim 4, wherein the control module is configured to control an operation of the at least one on/off valve based on the movement of the brake pedal.

6. The braking system of any one of claims 1 to 3, wherein the second valve assembly includes at least one proportional pressure control valve.

7. The braking system of claim 6, wherein the control module is configured to control an operation of the at least one proportional pressure control valve based on a distance of the movement of the brake pedal.

8. The braking system of claim 1 or 2, wherein the first valve assembly is a mechanically actuated valve assembly.

9. The braking system of any one of claims 1, 2 and 8, wherein the first valve assembly is mechanically connected to the brake pedal.

10. The braking system of claim 1 or 2, wherein the at least one brake assembly is associated with at least one of a pair of front wheels and a pair of rear wheels of the machine.

11. A machine comprising: a machine frame; a plurality of axles supported on the machine frame, wherein each of the plurality of axles support a pair of wheels; a brake pedal movable by an operator of the machine; and a braking system adapted to initiate at least one of a halting and deceleration of the machine based on a movement of the brake pedal, the braking system comprising: a source of hydraulic fluid; a first valve assembly in fluid communication with the source, wherein an operation of the first valve assembly is based on a movement of the brake pedal; an electro-hydraulic brake booster device that is operable based on the movement of the brake pedal, the electro-hydraulic brake booster device comprising: a second valve assembly in fluid communication with the source; and a control module communicably coupled with the second valve assembly, wherein the control module is configured to transmit control signals to the second valve assembly for operating the second valve assembly based on the movement of the brake pedal; and at least one brake assembly, the first valve assembly and the second valve assembly being connected in parallel between the source and each of the at least one brake assembly by selective fluid communication, wherein the at least one brake assembly is actuated based on fluid pressure received from the source via both the first valve assembly and the second valve assembly.

12. The machine of claim 11, wherein the source includes an accumulator for storing hydraulic fluid under pressure.

13. The machine of claim 11 or 12, wherein the second valve assembly includes at least one solenoid operated valve.

14. The machine of any one of claims 11 to 13, wherein the second valve assembly includes at least one on/off valve.

15. The machine of claim 14, wherein the control module is configured to control an operation of the at least one on/off valve based on the movement of the brake pedal.

16. The machine of any one of claims 11 to 13, wherein the second valve assembly includes at least one proportional pressure control valve.

17. The machine of claim 16, wherein the control module is configured to control an operation of the at least one proportional pressure control valve based on a distance of the movement of the brake pedal.

18. The machine of claim 11 or 12, wherein the first valve assembly is a mechanically actuated valve assembly.

19. The machine of any one of claims 11, 12 and 18, wherein the first valve assembly is mechanically connected to the brake pedal.

20. The machine of claim 11 or 12, wherein the at least one brake assembly is associated with at least one of a pair of front wheels and a pair of rear wheels of the machine.