Claims:
1. A hydraulic braking system (100) for a vehicle, the hydraulic braking system (100) operatively coupled to a brake pedal of the vehicle, the hydraulic braking system (100) comprising:
a first and a second sets of wheel brake cylinders (2, 4);
a first cylinder (10) configured to supply a pressurized fluid at a first cylinder pressure to the first and the second sets of wheel brake cylinders (2, 4), through a first fluid line (14) and a second fluid line (16), respectively, in response to a force exerted on the first cylinder (10) through the brake pedal of the vehicle;
a first vacuum booster (20) operatively connected between the first cylinder (10) and the brake pedal, the first vacuum booster (20) configured for augmenting the force exerted on the first cylinder (10) to increase the first cylinder pressure of the pressurized fluid;
an auxiliary cylinder (30) fluidly coupled to the second fluid line (16) for receiving the pressurized fluid at the first cylinder pressure from the first cylinder (10), the auxiliary cylinder (30) including a chamber and a piston slidably disposed within the chamber, and being configured to derive a piston force from the pressurized fluid at the first pressure;
a second cylinder (40) disposed downstream to and coupled to the auxiliary cylinder (30), the second cylinder (40) being configured to supply a pressurized fluid at a second cylinder pressure to the second set of wheel brake cylinders (4), through a third fluid line (18), in response to the piston force; and
a second vacuum booster (50) operatively connected to the second cylinder (40) for augmenting the piston force exerted on the second cylinder (40) to increase the second cylinder pressure of the pressurized fluid.

2. The hydraulic braking system (100) as claimed in claim 1, wherein the auxiliary cylinder (30) includes a stepped internal bore in the chamber, and a diameter of the stepped internal bore at an input end is more than a diameter of the stepped internal bore at an output end.

3. The hydraulic braking system (100) as claimed in claim 2, wherein the auxiliary cylinder (30) is adapted to receive the pressurized fluid at the first cylinder pressure at the input end of the stepped internal bore and the piston outputs the piston force at the output end of the stepped internal bore.

4. The hydraulic braking system (100) as claimed in claim 1, wherein an internal diameter of a bore of the auxiliary cylinder (30) is less than an internal diameter of a bore of the first cylinder (10).

5. The hydraulic barking system (100) as claimed in claim 1, including a vacuum circuit (90) operatively connected to the first vacuum booster (20) and the second vacuum booster (50).

6. The hydraulic barking system (100) as claimed in claim 1, including a brake fluid circuit (80) operatively connected to the first cylinder (10) and the second cylinder (40).

7. The hydraulic braking system (100) as claimed in claim 1, wherein the piston force is more than the force exerted on the brake pedal.

8. The hydraulic braking system (100) as claimed in claim 1, wherein the first cylinder (10) is a tandem master cylinder.

9. The hydraulic braking system (100) as claimed in claim 1, wherein the second cylinder (40) is a single piston cylinder.

10. The hydraulic barking system (100) as claimed in claim 1, wherein the second set of wheel brake cylinders (4) corresponds to rear wheels of the vehicle.

11. The hydraulic barking system (100) as claimed in claim 1, wherein the second set of wheel brake cylinders (4) corresponds to front wheels of the vehicle.

12. A vehicle including the hydraulic barking system (100) as claimed in claim 1.
, Description:TECHNICAL FIELD
[001] The present disclosure relates to the field of automobiles. Particularly, but not exclusively, the present disclosure relates to hydraulic braking system with booster mechanism for an automobile.

BACKGROUND
[002] The information in this section merely provides background information related to the present disclosure and may not constitute prior art(s) for the present disclosure.
[003] Commonly known techniques for improving the performance of a vehicle braking system include power assisted braking mechanism that often uses a fluid pressure actuator, such as a vacuum booster, to assist/boost a driver-exerted force on a brake pedal of the vehicle.
[004] However, it has been found that the existing vacuum assisted hydraulic brake system has limitations of being capable to properly and sufficiently utilize the brake system for the vehicles bearing vehicle gross weight up to 7.5 ton. For the vehicles bearing vehicle gross weight more than 7.5 ton, the existing vacuum assisted hydraulic brake system fails to provide desired brake performance. Further, there remains constraints on a size of the vacuum booster as their size cannot be increased beyond a certain limit due to vehicle packaging constrains.
[005] Currently, pneumatic S-cam braking systems are being used in the vehicles bearing weight above 7.5 ton. However, said pneumatic braking systems are expensive and heavier in weight in comparison to vacuum assisted hydraulic brakes.
[006] Therefore, there remains a need for an improved hydraulic braking system for a vehicle and that is adapted to overcome the problems identified above. Specifically, there remains a need for a hydraulic braking system that is assisted by vacuum booster(s) and capable of being used in the vehicles bearing gross vehicle weight more than 7.5 ton, that is being operable at less brake pedal travel and input force, that is cheaper and light in weight.

SUMMARY
[007] The one or more shortcomings of the prior art are overcome by an assembly as claimed and additional advantages are provided through the provision of assembly 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 a part of the claimed disclosure.
[008] In an aspect, the present disclosure relates to a hydraulic braking system for a vehicle. The hydraulic braking system is operatively coupled to a brake pedal of the vehicle. The hydraulic braking system comprises a first and a second sets of wheel brake cylinders. The hydraulic braking system includes a first cylinder configured to supply a pressurized fluid at a first cylinder pressure to the first and the second sets of wheel brake cylinders, through a first fluid line and a second fluid line, respectively, in response to a force exerted on the first cylinder through the brake pedal of the vehicle. The hydraulic braking system further includes a first vacuum booster operatively connected between the first cylinder and the brake pedal, the first vacuum booster configured for augmenting the force exerted on the first cylinder to increase the first cylinder pressure of the pressurized fluid. The hydraulic braking system furthermore includes an auxiliary cylinder fluidly coupled to the second fluid line for receiving the pressurized fluid at the first cylinder pressure from the first cylinder, the auxiliary cylinder including a chamber and a piston slidably disposed within the chamber, and being configured to derive a piston force from the pressurized fluid at the first pressure. The hydraulic braking system also includes a second cylinder disposed downstream to and coupled to the auxiliary cylinder, the second cylinder being configured to supply a pressurized fluid at a second cylinder pressure to the second set of wheel brake cylinders, through a third fluid line, in response to the piston force. Also, the hydraulic braking system includes a second vacuum booster operatively connected to the second cylinder for augmenting the piston force exerted on the second cylinder to increase the second cylinder pressure of the pressurized fluid.
[009] In an embodiment, the auxiliary cylinder includes a stepped internal bore in the chamber, and a diameter of the stepped internal bore at an input end is more than a diameter of the stepped internal bore at an output end.
[010] In an embodiment, the auxiliary cylinder is adapted to receive the pressurized fluid at the first cylinder pressure at the input end of the stepped internal bore and the piston outputs the piston force at the output end of the stepped internal bore.
[011] In an embodiment, an internal diameter of a bore of the auxiliary cylinder is less than an internal diameter of a bore of the first cylinder.
[012] In an embodiment, a vacuum circuit is operatively connected to the first vacuum booster and the second vacuum booster.
[013] In an embodiment, a brake fluid circuit is operatively connected to the first cylinder and the second cylinder.
[014] In an embodiment, the piston force is more than the force exerted on the brake pedal.
[015] In an embodiment, the first cylinder is a tandem master cylinder.
[016] In an embodiment, the second cylinder is a single piston cylinder.
[017] In an embodiment, the second set of wheel brake cylinders correspond to rear wheels of the vehicle.
[018] In an embodiment, the second set of wheel brake cylinders correspond to front wheels of the vehicle.
[019] In another aspect, the present disclosure relates to a vehicle including the hydraulic barking system as described above.
[020] 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.
[021] 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 FIGURES
[022] The novel features and characteristics of the disclosure are set forth in the description. The disclosure itself, however, as well as a preferred mode of use, further objectives, and advantages thereof, will best be understood by reference to the following description of an illustrative 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 illustrates a schematic diagram of a hydraulic braking system, and components thereof, in accordance with an embodiment of the present disclosure.

[023] Skilled artisans will appreciate that elements in the drawings are illustrated for simplicity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the drawings may be exaggerated relative to other elements to help to improve understanding of embodiments of the present disclosure.

DETAILED DESCRIPTION
[024] While the disclosure is susceptible to various modifications and alternative forms, specific embodiment thereof has been shown by way of example in the figures and will be described in detail 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 alternatives falling within the spirit and the scope of the disclosure as defined by the appended claims.
[025] Before describing detailed embodiments, it may be observed that the novelty and inventive step that are in accordance with the present disclosure resides in a hydraulic braking system for a vehicle. It is to be noted that a person skilled in the art can be motivated from the present disclosure and modify the various constructions of the hydraulic braking system. However, such modification should be construed within the scope of the disclosure. Accordingly, the drawings are showing only those specific details that are pertinent to understanding the embodiments of the present disclosure so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having benefit of the description herein. Further, hydraulic braking system may be employed in any vehicle including but not limiting to heavy and light commercial vehicles, and passenger vehicles. However, neither the complete braking system nor the vehicle is illustrated in the figure for the purpose of simplicity.
[026] The terms “comprises”, “comprising”, or any other variations thereof, are intended to cover a non-exclusive inclusions, such that a setup, device that comprises a list of components does not include only those components but may include other components not expressly listed or inherent to such setup or device. In other words, one or more elements in a system or apparatus proceeded by “comprises… a” does not, without more constraints, preclude the existence of other elements or additional elements in the system or apparatus.
[027] Reference will now be made to the exemplary embodiments of the disclosure, as illustrated in the accompanying drawings. Wherever possible same numerals will be used to refer to the same or like parts.
[028] Embodiments of the disclosure are described in the following paragraphs with reference to FIG. 1. In the figure, the same element or elements which have same functions are indicated by the same reference signs.
[029] Referring to FIG. 1, a schematic diagram of a hydraulic braking system (100) of a vehicle (not shown) in accordance with an embodiment of the present disclosure, is disclosed. Within the scope of the present disclosure, the hydraulic braking system (100) is adapted to be assisted by vacuum booster(s) and capable of being used in heavy vehicles, for example the vehicles bearing gross vehicle weight more than 7.5 ton, capable of producing desired brake performance at less brake pedal travel and input force, is cheaper and light in weight.
[030] The hydraulic braking system (100) comprises a first and a second sets of wheel brake cylinders (2, 4), a first cylinder (10), a first vacuum booster (20), an auxiliary cylinder (30), a second cylinder (40) and a second vacuum booster (50), operably and fluidly coupled to each other. In accordance with the present disclosure, the hydraulic braking system (100) includes four wheel brake cylinders forming the first set of wheel brake cylinders (2) and the second set of wheel brake cylinders (4), each of which is composed of two wheel brake cylinders. In an embodiment, the first and the second sets of wheel brake cylinders (2, 4) may be connected respectively to front and rear wheels of the vehicle. In alternate embodiments, the first and the second sets of wheel brake cylinders (2, 4) may be connected respectively diagonally to one front and the opposite rear wheel of the vehicle, depending upon the type of vehicle in which the hydraulic braking system (100) is installed. Without deviating from the scope of the present disclosure, the hydraulic braking system (100) may include eight wheel brake cylinders forming the first set of wheel brake cylinders (2) and the second set of wheel brake cylinders (4), in which case each of the first set of wheel brake cylinders (2) and the second set of wheel brake cylinders (4) is composed of four wheel brake cylinders. In said configuration, each wheel of the front wheels and the rear wheels of the vehicle may be coupled to two wheel brake cylinders.
[031] The hydraulic braking system (100) includes the first cylinder (10) that is adapted to supply a pressurized fluid at a first cylinder pressure to the first set of wheel brake cylinders (2) and the second set of wheel brake cylinders (4), in response to a force exerted, by a driver of the vehicle, on a brake pedal (not shown) of the vehicle. In accordance with the present disclosure, the first cylinder (10) may be operably coupled to the brake pedal of the vehicle by means of a push rod (12) connected to the brake pedal at one end and to a piston (not shown) of the first cylinder (10) at the other end. During an operation of the hydraulic braking system (100), when the driver exerts the force on the brake pedal, the push rod (12) attached to the brake pedal applies an input force to one or more pistons (not shown) located inside of the first cylinder (10). It is pertinent to note that the input force applied to the first cylinder piston(s) is greater than the force exerted on the brake pedal, due to the leverage provided by a length of the brake pedal and/or a configuration of the push rod (12).
[032] The hydraulic braking system (100) further includes a first fluid line (14) and a second fluid line (16) configured to couple the first cylinder (10) to the first set of wheel brake cylinders (2) and the second set of wheel brake cylinders (4), respectively. In accordance with the present disclosure, the hydraulic braking system (100) is configured to supply the pressurized fluid at the first cylinder pressure from the first cylinder (10) to the first set of wheel brake cylinders (2) and the second set of wheel brake cylinders (4) through the first fluid line (14) and the second fluid line (16), respectively. In an embodiment, the first cylinder (10) of the hydraulic braking system (100) is a tandem master cylinder including two pistons operating in series within a common bore of the first cylinder (10). In said embodiment, the first fluid line (14) may be adapted to fluidly couple one of the two pistons of the first cylinder (10) with the first set of wheel brake cylinders (2), and the second fluid line (16) may be adapted to fluidly couple other of the two pistons of the first cylinder (10) with the second set of wheel brake cylinders (4).
[033] Additionally, the hydraulic braking system (100) of the present disclosure may include a brake fluid circuit (80) operatively connected to the first cylinder (10) for supplying fluid to the first cylinder (10). The brake fluid circuit (80) may include a brake fluid reservoir (82) containing the fluid and brake fluid lines (84) to supply the fluid from the brake fluid reservoir (82) to the first cylinder (10).
[034] In accordance with the present disclosure, the hydraulic braking system (100) includes the first vacuum booster (20) operatively connected between the first cylinder (10) and the brake pedal of the vehicle. The first vacuum booster (20) may be configured for augmenting the force exerted on the first cylinder (10) to increase the first cylinder pressure of the pressurized fluid. Within the scope of the present disclosure, the push rod (12) may extend through the first vacuum booster (20) that includes a diaphragm (not shown), having a large area, connected to the push rod (12). The diaphragm separates and seals a forward fluid chamber of the first vacuum booster (20) from a rear fluid chamber of the first vacuum booster (20). The forward fluid chamber may be connected to a vacuum circuit (90), including a vacuum tank (92) and a vacuum pump (94), and the rear fluid chamber may be vented to atmosphere via a port.
[035] As the driver exerts the force on the brake pedal, the push rod (12) operates a control valve (not shown) in the first vacuum booster (20), in a manner known in the art, to open the forward chamber to the vacuum circuit (90). As the vacuum circuit (90) evacuates the forward chamber, atmospheric air pressure in the rear chamber acting against the diaphragm area provides an additive force that substantially increases the input force applied to the first cylinder (10) by the push rod (12), in comparison to the force exerted on the push rod (12) by the brake pedal of the vehicle. Accordingly, in said manner, the first vacuum booster (20) augments the force applied to the brake pedal by the driver in a manner that causes the first cylinder (10) to provide substantially high pressurized fluid in the first fluid line (14) and the second fluid line (16), thereby increasing the braking force while keeping the force that the driver must apply to the brake pedal at a modest value.
[036] The hydraulic braking system (100) of the present disclosure further includes the auxiliary cylinder (30) fluidly coupled to the second fluid line (16) for receiving the pressurized fluid at the first cylinder pressure from the first cylinder (10). In an embodiment, the auxiliary cylinder (30) may include an inlet port for receiving the pressurized fluid at the first cylinder pressure, through the second fluid line (16), from the first cylinder (10). The auxiliary cylinder (30) may further include a chamber (not shown) having a stepped internal bore, and a piston slidably disposed within the stepped internal bore (or the chamber). In an embodiment, the piston disposed within the stepped internal bore may be a stepped piston formed of a shape complimentary to a shape of the internal bore. In an embodiment, the auxiliary cylinder is a single piston cylinder. In another embodiment, the auxiliary cylinder is a slave cylinder.
[037] The stepped internal bore of the auxiliary cylinder (30) may be formed of a configuration in which a diameter of the stepped internal bore at an input end is more than a diameter of the stepped internal bore at an output end. Accordingly, it can be contemplated that the piston has a larger end (at the input end of the stepped bore) exposed to the pressurized fluid at the first cylinder pressure at the inlet port. The pressure applied by the pressurized fluid at the first cylinder pressure to the larger end of the piston, in the auxiliary cylinder, generates a piston force, at the output end of the stepped internal bore, which is derivable by a piston rod of the auxiliary cylinder disposed at the output end of the stepped internal bore. By virtue of the difference in area between the input end and the output end of the stepped internal bore, the piston force derived by the piston rod is greater than a force corresponding to the pressurised fluid at the first cylinder pressure acting on the large end of the piston, according to the principles of hydraulics.
[038] The quantum of the piston force is directly proportional to a ratio of the area of the input end and the output end of the stepped internal bore. For instance, where the input end of the stepped internal bore has an area approximately twice as large as the area of the output end, the piston force derived by the piston rod will be approximately double than the force corresponding to the pressurised fluid at the first cylinder pressure acting on the large end of the piston. Within the scope of the present disclosure, an average diameter of the internal bore of the auxiliary cylinder (30) is less than an average diameter of a bore of the first cylinder (10) for further augmenting the quantum of the piston force derived by the piston rod. In an exemplary embodiment, the average diameter of the internal bore of the auxiliary cylinder (30) is 25 percent of the average diameter of the bore of the first cylinder (10). Accordingly, the piston force may be at least equal to the force exerted by the driver on the brake pedal of the vehicle. It can therefore be contemplated that the piston force may either be equal to or more than the force exerted by the driver on the brake pedal of the vehicle.
[039] The hydraulic braking system includes the second cylinder (40) that is disposed downstream to the auxiliary cylinder (30) and is coupled to the auxiliary cylinder (30). The second cylinder (40) may be adapted to supply a pressurized fluid at a second cylinder pressure to the second set of wheel brake cylinders (4), in response to the piston force derived by the piston rod. In accordance with the present disclosure, the second cylinder (40) is operably coupled to the piston rod of the auxiliary cylinder (30). During an operation of the hydraulic braking system (100), the piston rod actuates the second cylinder (40) to generate and supply the pressurized fluid at the second cylinder pressure to the second set of wheel brake cylinders (4). In an embodiment, an input force exerted on second cylinder piston may be greater than the piston force of the piston rod, on basis the coupling between the auxiliary cylinder (30) and the second cylinder (40) and a configuration of the piston rod.
[040] The hydraulic braking system (100) further includes a third fluid line (18) connecting the second cylinder (40) to the second set of wheel brake cylinders (4). In accordance with the present disclosure, the hydraulic braking system (100) is configured to supply the pressurized fluid at the second cylinder pressure from the second cylinder (40) to the second set of wheel brake cylinders (4) through the third fluid line (18). Without deviating from the scope of the present disclosure, the second cylinder (40) may be a tandem master cylinder or a single piston cylinder. Also, the second cylinder (40) may be fluidly coupled with the brake fluid circuit (80) for receiving the fluid from the brake fluid reservoir (82) through a brake fluid line (86).
[041] Further, the hydraulic braking system (100) includes the second vacuum booster (50) operatively connected to the second cylinder (40) and the piston rod of the auxiliary cylinder (30). The second vacuum booster (50) is configured for augmenting the piston force exerted on the second cylinder (40) to increase the second cylinder pressure of the pressurized fluid. Within the scope of the present disclosure, the piston rod may extend through the second vacuum booster (50) that includes a diaphragm (not shown), having a large area, connected to the piston rod. The diaphragm separates and seals a forward fluid chamber of the second vacuum booster (50) from a rear fluid chamber of the second vacuum booster (50). The forward fluid chamber may be connected to the vacuum circuit (90) and the rear fluid chamber may be vented to atmosphere via a port.
[042] Similar to the operation of the first vacuum booster (20), the piston rod operates a control valve (not shown) in the second vacuum booster (50), in a manner known in the art, to open the forward chamber to the vacuum circuit (90). As the vacuum circuit (90) evacuates the forward chamber, atmospheric air pressure in the rear chamber acting against the diaphragm area provides an additive force that substantially increases the piston force applied to the second cylinder (40) by the piston rod. Accordingly, in said manner, the second vacuum booster (50) augments the piston force applied to the second cylinder (40) that causes the second cylinder (40) to provide substantially high pressurized fluid to the third fluid line (18), thereby increasing the braking force at the second set of wheel brake cylinders (4).
[043] Within the scope of the present disclosure, during operation of the hydraulic braking system (100), the first cylinder (10) supplies the pressurized fluid at the first cylinder pressure to the first set of wheel brake cylinders (2). Likewise, the second cylinder (40) supplies the pressurized fluid at the second cylinder pressure to the second set of wheel brake cylinders (4). Upon receiving pressurized fluid from their respective cylinders, the first and the second set of wheel brake cylinders (2, 4) are being actuated to apply brakes to the wheels of the vehicle, thereby decelerating/stopping the vehicles. In an embodiment, the second set of wheel brake cylinders (4) may correspond to the rear wheels of the vehicle. In alternate embodiment, the set of wheel brake cylinders (4) may correspond to the front wheels of the vehicle.
[044] The function and operation of the hydraulic braking system of the present disclosure shall be described in the subsequent paragraphs.
[045] For decelerating/stopping the heavy vehicles, for example, a vehicle bearing gross vehicle weight more than 7.5 ton with a desired braking rate, for example a braking rate of 5m/s2, the present disclosure provides an improved hydraulic braking system (100) that can provide desired brake performance, unlike the conventional hydraulic brake systems. The hydraulic braking system (100) comprises the first and the second sets of wheel brake cylinders (2, 4), the first cylinder (10), the first vacuum booster (20), the auxiliary cylinder (30), the second cylinder (40) and the second vacuum booster (50), operably and fluidly coupled to each other.
[046] When the driver of the vehicle exerts a force on the brake pedal of the vehicle to decelerate the vehicle, the first cylinder (10) supplies the pressurised fluid at the first cylinder pressure to the first and the second sets of wheel brake cylinders (2, 4), through the first fluid line (14) and the second fluid line (16). Said pressurized fluid at the first cylinder pressure corresponds to the fluid which has been pressurized in response to the force exerted on the first cylinder (10) through the brake pedal of the vehicle and being augmented by the first vacuum booster (20) operatively connected between the first cylinder (10) and the brake pedal.
[047] Thereafter, the pressurized fluid at the first cylinder pressure is being received by the auxiliary cylinder (30) at the inlet port thereof, through the second fluid line (16), and the auxiliary cylinder (30) derives the piston force, which is at least equal to the force exerted on the brake pedal, from the pressurized fluid at the first cylinder pressure using the stepped internal bore-piston arrangement. The auxiliary cylinder (30) further actuates the second cylinder (40).
[048] Upon actuation by the auxiliary cylinder (30), the second cylinder (40) supplies the pressurized fluid at the second cylinder pressure to the second sets of wheel brake cylinders (4), through the third fluid line (18). Said pressurized fluid at the second cylinder pressure corresponds to the fluid which has been pressurized in response to the piston force exerted on the second cylinder (40) and being augmented by the second vacuum booster (50) operatively connected between the second cylinder (40) and the auxiliary cylinder (30).
[049] As forestated, the first cylinder (10) supplies the pressurized fluid at the first cylinder pressure to the first set of wheel brake cylinders (2) and the second cylinder (40) supplies the pressurized fluid at the second cylinder pressure to the second set of wheel brake cylinders (4) to actuate the wheel brake cylinders, thereby decelerating/stopping the vehicles.
[050] In accordance with the configuration of the hydraulic braking system (100) of the present disclosure, the driver is able to obtain the desired braking force from the system keeping the force that the driver must apply to the brake pedal at a modest value and the first and the second set of the wheel brake cylinders (2, 4) achieve same brake force with less pedal travel.
[051] Also, the auxiliary cylinder (30) in addition to the two vacuum boosters, i.e., the first vacuum booster (20) and the second vacuum booster (50), facilitate to maintain desired fluid pressure in the hydraulic braking system (100) and make the system suitable for being used in the vehicles bearing gross vehicle weight more than 7.5 ton. Also, the hydraulic braking system (100) is cheaper to manufacture and is lighter in weight compared to the conventional pneumatic braking systems.
[052] While considerable emphasis has been placed herein on the particular features of this disclosure, it will be appreciated that various modifications can be made, and that many changes can be made in the preferred embodiments without departing from the principles of the disclosure. These and other modifications in the nature of the disclosure or the preferred embodiments will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation.

REFERAL NUMERICALS

PARTICULARS REFERRAL NUMERAL
Hydraulic Braking System 100
First set of wheel brake cylinders 2
Second set of wheel brake cylinders 4
First cylinder 10
Push rod 12
First fluid line 14
Second fluid line 16
Third fluid line 18
First vacuum booster 20
Auxiliary cylinder 30
Second cylinder 40
Second vacuum booster 50
Brake fluid circuit 80
Brake fluid reservoir 82
Brake fluid lines 84
Brake fluid line 86
Vacuum circuit 90
Vacuum tank 92
Vacuum pump 94

EQUIVALENTS:
[053] The embodiments herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
[054] The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.
[055] Throughout this specification the word “comprise”, or variations such as “comprises” or “comprising”, will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.
[056] The use of the expression “at least” or “at least one” suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the disclosure to achieve one or more of the desired objects or results.
[057] Any discussion of documents, acts, materials, devices, articles and the like that has been included in this specification is solely for the purpose of providing a context for the disclosure. It is not to be taken as an admission that any or all of these matters form a part of the prior art base or were common general knowledge in the field relevant to the disclosure as it existed anywhere before the priority date of this application.
[058] The numerical values mentioned for the various physical parameters, dimensions or quantities are only approximations and it is envisaged that the values higher/lower than the numerical values assigned to the parameters, dimensions or quantities fall within the scope of the disclosure, unless there is a statement in the specification specific to the contrary.