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Title:
BRAKE ASSEMBLY FOR A VEHICLE
Document Type and Number:
WIPO Patent Application WO/2021/152619
Kind Code:
A1
Abstract:
The present invention relates to brake assembly (100) for a vehicle, wherein said brake assembly (100) configured to a proportionating device (204). The proportionating device (204) provided substantially ahead of the seat assembly (111) and located within the imaginary planes such that one end of said proportionating device (204) functionally engages at least one end of a center brake line assembly (206) and another end of said proportionating device (204) functionally engages with at least one end of a tandem master cylinder (211).The present subject matter avoids the accidents due to leakage in the proportionating device (204), because it is externally visible to the operator as located ergonomically and coming within best conical view of the operator.

Inventors:
MUKTHA SAI KUMAR (IN)
GOLLAPALLI SURYA GANGADHARA RAVIKANTH (IN)
MOSALI NAGARJUNREDDY (IN)
Application Number:
PCT/IN2021/050074
Publication Date:
August 05, 2021
Filing Date:
January 23, 2021
Export Citation:
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Assignee:
TVS MOTOR CO LTD (IN)
International Classes:
B60T8/26; B60T7/04; B60T11/12
Foreign References:
US5544946A1996-08-13
US20060055234A12006-03-16
Download PDF:
Claims:
We Claim:

1. A brake assembly for a vehicle (100), said vehicle (100) comprising: a frame assembly (F), said frame assembly (F) includes at least one center rail (208), said center rail (208) having an imaginary plane C-C’ passing in the longitudinal direction (YY’) of the vehicle (100); a seat assembly (111) to seat a driver; and, a proportionating device (204), wherein said proportionating device (204) is configured to be disposed substantially ahead of the seat assembly

(111) and located within the imaginary plane C-C’ and an imaginary plane B-B’ at a predetermined distance (Dra) from said plane C-C’, wherein one end of said proportionating device (204) functionally engages with at least one end of a center brake line assembly (206) and another end of said proportionating device (204) functionally engages with at least one end of a tandem master cylinder (211).

2. A brake assembly for a vehicle (100), said vehicle (100) comprises: a frame assembly (F), said frame assembly (F) includes at least one center rail (208), said center rail (208) having an imaginary plane C-C’ passing in a longitudinal direction (YY’) of the vehicle (100); a seat assembly (111); and, a proportionating device (204), wherein said proportionating device (204) is configured to be disposed substantially ahead of the seat assembly (111) and located within the imaginary plane C-C’ and an imaginary plane A-A’ at a predetermined distance (Dla) from said plane C-C’, wherein one end of said proportionating device (204) functionally engages with at least one end of a center brake line assembly (206) and another end of said proportionating device (204) functionally engages with at least one end of a tandem master cylinder (211).

3. The brake assembly for a vehicle (100) as claimed in claim 1 or claim 2, wherein said center rail (208) comprises a channel which has an interior bound by a vertical side walls (208b) a horizontal top wall (208a) and bottom wall (208c) which extend from top and bottom of the vertical walls

(208b) toward the top and bottom walls of a cross member (302), and other end is connected to a main tube (210) of said frame assembly (F).

4. The brake assembly for a vehicle (100) as claimed in claim 1 or claim 2, wherein said center brake line assembly (206) is enclosed within the channel provided in the center rail (208).

5. The brake assembly for a vehicle (100) as claimed in claim 1, wherein said imaginary plane B-B’ is substantially parallel to the C-C’ plane such that imaginary plane B-B’ is having the predetermined distance (Dra) from the

C-C’ plane in the lateral direction (LL’) of the vehicle (100).

6. The brake assembly for a vehicle (100) as claimed in claim 2, wherein said imaginary plane A-A’ is substantially parallel to the C-C’ plane such that imaginary plane A-A’ is having the predetermined distance (Dla) from the

C-C’ plane in the lateral direction (LL’) of the vehicle (100).

7. The brake assembly for a vehicle (100) as claimed in claim 5 or claim 6, wherein said predetermined distance (Dla, Dra) ranges from 5 millimeter to 100 millimeter.

8. The brake assembly for a vehicle (100) as claimed in claim 1 or claim 2, wherein said center brake assembly (206) includes at least one center brake line (206a), wherein said center brake line (206a) configured to have a S- bend (207) disposed in the driver compartment or region.

9. The brake assembly for a vehicle (100) as claimed in claim 8, wherein said S-bend (207) enables the connection of center brake line (206a) to the proportionating device (204). 10. The brake assembly for a vehicle (100) as claimed in claim 8, wherein said

S-bend (207) is partially enclosed within the said channel in the center rail (208).

11. The brake assembly for a vehicle (100) as claimed in claim 1 or claim 2, wherein said center brake line assembly (206) connected to a rear brake line assembly (202) at one of its end using at least one T-joint (205).

12. The brake assembly for a vehicle (100) as claimed in claim 11, wherein said rear brake line assembly (202) includes at least two brake lines (202a, 202b) functionally connected to the rear wheels (107) respectively.

Description:
BRAKE ASSEMBLY FOR A VEHICLE

TECHNICAL FIELD

[0001] The present subject matter relates to a multi-track vehicle. More particularly, it relates to a brake assembly for a multi-track vehicle.

BACKGROUND

[0002] Over the past few years, the public transport means becomes predominant means which include light commercial multi wheeled multi-track vehicles. Such vehicles especially in developing countries is one of the chief modes of transport. The typical public transport is operated day and night on roads and such increasing number of vehicles on road led to many innovations. Improving the comfort and safety of vehicle and also the safety of passengers in public transport is always a big challenge for automobile manufacturers as the increased safety features requires lot of controls and indication which needs to be accommodated within defined space. But these vehicles must withstand wide temperature ranges as well as shock, different road conditions, vibration abuse as well as need to have robust braking system for safe retardation or reliable stopping. BRIEF DESCRIPTION OF THE DRAWINGS

[0003] The detailed description is described with reference to an embodiment of a brake assembly for a vehicle with the accompanying figures. The same numbers are used throughout the drawings to reference like features and components.

[0004] Fig. 1 illustrates side view of the vehicle as per embodiment of the present invention.

[0005] Fig. 2 illustrates the partial rear perspective view of the vehicle where few parts are omitted as per embodiment of the present invention.

[0006] Fig. 3(a) and Fig. 3(b) illustrates the top view and rear side cut section view across Z-Z axis of the vehicle respectively where few parts are omitted as per embodiment of the present invention. [0007] Fig. 4(a) and Fig. 4(b) illustrates the side view and top view of the vehicle respectively where few parts are omitted as per embodiment of the present invention.

[0008] Fig. 5(a) and 5(b) illustrates the comparison of conventional braking system and proposed braking system through graphical representation as per embodiment of the present invention.

DETAILED DESCRIPTION [0009] Various features and embodiments of the present invention here will be discernible from the following further description thereof, set out hereunder. It is contemplated that the concepts of the present invention may be applied to any type of vehicle employing the similar configuration within the spirit and scope of this invention. Further "front" and "rear", and "left" and "right" referred to in the ensuing description of the illustrated embodiment refer to front and rear, and left and right directions as seen from a rear portion of the vehicle and looking forward. Furthermore, a longitudinal axis unless otherwise mentioned, refers to a front to rear axis relative to the vehicle, while a lateral axis unless otherwise mentioned, refers generally to a side to side, or left to right axis relative to the vehicle. The detailed explanation of the constitution of parts other than the present subject matter which constitutes an essential part has been omitted at suitable places.

[00010] In present day road traffic, it is important to enhance the safety of a vehicle and its occupants; therefore, efforts are being made to assist the operator in routine driving operations as well as in extraordinary situations using systems that intervene automatically in the control of the multi-wheeled vehicle or of particular vehicle system like braking system. Hence it is important in all road conditions to enhance transverse stability of the vehicle in dynamically critical situations, particularly in situations brought about and influenced by braking action taken by the operator. During the braking process, typically the pedal force acts through a mechanical hydraulic system to apply a retarding torque to each wheel of the vehicle. The braking torque is opposed by the inertia of the wheel and the frictional force between the tire and the road, which results bringing the vehicle into deceleration mode. Consequently, the control of the deceleration of a vehicle through brake pedal force depends on the static and dynamic characteristics of the entire brake system, when brake force applied on the brake pedal is greater than the required braking force the wheel locks, which leads to panic braking or skidding scenario. It can further be aggravated by the road friction which if low may lead to wheel slip to the nominal slip value especially in rural areas or hilly areas etc. This scenario is especially true where the coefficient of friction of rural areas road surfaces can be less due presence of sand or mud etc. The panic situation leads many average operators to apply the brakes with some period of hesitation at the beginning. This hesitation has a large influence on the stopping distance as well as safety since it occurs at the highest vehicle velocity. Application of such panic brakes in undesirable driving and / or adverse road friction conditions, makes the vehicle unstable leading to locked wheel condition. While in a 4 wheeled vehicle, this leads to slip of front or rear wheels depending on which brake is being applied or which wheel is tending to lock, the situation becomes more precarious in a 3 wheeled vehicle (one front wheel) when front wheel tends to get into wheel lock condition. Typically 3 and 4 wheeled vehicles configured with hydraulic brake system have brake pressure / forces proportionately distributed to front & rear wheels depending on various factors like calibration of the vehicle tyre characteristics, vertical load distribution on each wheel etc. , A vehicle with locked front wheels can have a stable straight ahead motion, however, the steerability is lost because the friction forces in the tire road contact are counter directed towards the sliding motion for locked wheels. Conventionally, under normal driving conditions, the side / steering forces on rolling wheels tend to return the vehicle to straight line motion. Furthermore, a vehicle with locked rear wheels will become unstable. The vehicle turns around and ends up in sliding as side forces on rolling front wheels tend to increase the unstable motion. Potential safety concern arises which can be fatal & can lead to toppling over of the vehicle.

[00011] Thus, the brake force applied to each one of the wheels must be proportionate to the vertical load acting on wheel for instance, in a 3 wheeled multi-track vehicle with rear mounted powertrain or high percentage of load distribution on the rear wheels, 2/3 rd percent of total brake forces are typically supplied or distributed to the front wheel brake assemblies while l/3 rd percent thereof are supplied to the rear wheel brake assemblies during predetermined high decelerations the vehicle brake load applied onto the front wheels is greater than that applied onto the rear wheels due to dynamic load transfer of the vehicle i.e. high dynamic load transfer during brake application. Further, due to improper proportioning, poor calibration, panic scenario, undesirable road friction condition etc. there is always a chance of wheels getting locked up due to brake force i.e. the improper distribution of the brake force at each of the wheels based on the load or pressure acting on the wheels not being adequately balanced. Hence, the various proportioning devices are designed to prevent wheel lock up. The above challenges become all the more critical when the vehicle under consideration is a public transport vehicle like a 3 -wheeler auto or a 4-wheeler cab which needs to be up & running throughout day & night with negligible time for service & maintenance. [00012] Typically, as explained above, the brake pressure is higher at front end of the proportionating devices specially during high deceleration. Thus, these said front brake devices require frequent servicing to prevent any leakage or damage. But the arrangement of the devices is at locations which is difficult to access for the operators and requires jack and external means to access these proportionating devices. This increases the serviceability time and cost of service operation due to increased workman hours. Furthermore, any loss of brake fluid can result from a small leak in one of the components of the brake assembly like hoses/bundies or seals or fittings or proportionating devices which are leading to the wheel brake assembly. Typically, low viscosity fluid may be preferred to improve the response time of the brake system i.e. low fluid resistance, this is contradictory to the ease of leakage property. Low fluid viscosity can lead to high affinity of undesirable leak that may occur. Since the hydraulic system depends on brake fluid i.e. light viscous fluid, this brake fluid seeps past the seals, and the leak is usually infinitesimal and unnoticed until it is completely depleted or functionally ineffective braking. Thus, during minor leads, in each application of the brake pedal, contents of the master cylinder gets depleted to a dangerous level, like completely emptying the master cylinder in a short time. This becomes a grave danger when leakage is unattended during driving condition as proportioning devices are hard to access or visually inspect. Thus, these known designs are far less effective in delivery safe braking system as well as not very efficient because these vehicles need frequent road side assistance including towing of the vehicle due to complete loss of brake fluid from several causes. If left unnoticed or unattended, consequential safety hazard in form of accident or toppling are further detrimental problems to be addressed. While on one side it is important that the braking system responds in short time efficiently to deliver safe braking on demand, there are considerable challenges in ensuring reliable braking with ease of service & maintenance while ensuring compact clean looks of the system all of which to be achieved at lowest cost impact.

[00013] Secondly, public transport vehicles are generally operated intermittently for 12-14 hours a day to enable the operator to maximize his earnings. Further, due to dusty and muddy terrain in most areas and also because of the largely unmetalled roads connecting the villages to the cities lot of undesirable foreign matter including dust affects the durability and performance of braking operation. Even due to the vibration the various fittings may get loosened and may lead to falling of the various parts of the brake assembly like proportioning devices during vehicle movement. In some known arts, in brake assembly includes plurality of brackets to the mount the various parts like proportionating devices to the frame assembly the service operation time is increased due to plurality of brackets. Furthermore, any break or leakage in any of the lines leads to pressure drop in the other lines, thereby resulting in failure of the whole system. Such failures are very common and often result in serious accidents. Thus, brake lines, proportioning devices among others, are components whose performance in the vehicle has a direct impact on its safety and reliability.

[00014] Therefore, it is a challenge for designers to design an efficient braking system where braking efficiency defined for a complete vehicle including high dynamic load transfer in addition to front axle static load and rear axle static load is met while achieving safe, reliable & quick system performance without leading to wheel locking condition with minimum service downtime, ease of access for service cum periodic inspection & thereby improve the safety of the vehicle & its occupants as a whole.

[00015] It is therefore object of the present invention is to provide a braking assembly having a pressure responsive means for actuating a rear brakes to avoid wheel locking during high deceleration.

[00016] It is yet another object of the present invention is to provide a brake assembly that is designed to make it easy to perform servicing as well as improve external appearance.

[00017] It is an object of the present invention to provide a brake assembly which is designed to decrease the response time of the brake system of the vehicle by reducing the fluid resistance.

[00018] It is an object of the present invention to provide a brake assembly having a proportionating device provided in optimum location so that any leakage can be easily spotted by the operator even in driving condition without need for frequent inspection at workshops.

[00019] Thus, there is a need of an improved braking system for a 3-wheeled & 4-wheeled vehicle which obviates the above-mentioned problems & other problems in known arts. The present invention provides a brake assembly for a 3-wheeled multi-track vehicle comprising a frame assembly includes at least one center rail. The center rail comprising a channel which has an interior bounded by a vertical walls and by horizontal top and bottom walls. The horizontal top and bottom which extend from top and bottom of the vertical walls toward the top and bottom walls of a cross member, and other end is connected to a main tube portion of said frame assembly. A proportionating device, wherein said proportionating device is disposed substantially ahead of the seat assembly and between imaginary plane C-C’ and imaginary plane B-B’ as per preferred embodiment of the present invention. The imaginary plane B-B’ is substantially parallel to the imaginary plane C-C’ wherein said imaginary plane B-B’ having predetermined distance (Dra) in range of 5 millimeter to 100 millimeter from the imaginary plane C-C’. As per alternative embodiment the proportionating device is provided between imaginary plane C-C’ and imaginary plane A-A’ wherein imaginary plane A-A is substantially parallel to the imaginary plane C-C\ The imaginary plane C-C’ is passing through the center of the center rail in the longitudinal direction of the vehicle. The one end of said proportionating device functionally engages at least one end of a center brake line assembly and another end of said proportionating device functionally engages with at least one end of tandem master cylinder. The center brake line assembly is enclosed within the channel provided in the center rail.

[00020] The aforesaid and other advantages of the present subject matter would be described in greater detail in conjunction with the figures in the following description with an embodiment of the brake assembly of a 3 -wheeled vehicle.

[00021] Fig.l illustrates a side view of an exemplary three-wheeled vehicle (100) (hereinafter ‘vehicle’), in accordance with one embodiment of the present invention. The vehicle has a front cowl (105) supporting a windscreen (102). The lower portion of the front cowl (105) is connected to a front wheel (104) with a wheel cover (103) disposed in between by using steering tube assembly (not shown). A handle bar assembly (114) is present behind the front cowl (105) which is used to operate the said vehicle (100). In this view, a steering tube assembly (not shown) is disposed along the steering axis of the vehicle (100). Further, as per one embodiment, the vehicle (100) is divided into two compartments along the line X-X’; a driver/user compartment (D) having a seat assembly (111) and a passenger compartment (P) having at least one passenger seat assembly (113). A rear cabin (106) along with the passenger compartment (P) of the vehicle (100) is supported on a pair of rear wheels (107) located on either side of the longitudinal axis (YY) of the vehicle (100). The vehicle (100) comprises a chassis frame structure (not shown), extending from a front portion (F) to a rear portion (R) along the vehicle longitudinal axis (YY). A floorboard (108) is extending from the bottom portion of the front cowl (105) to the rearward direction of the vehicle (100), supported by the frame assembly (F). The rear suspension includes a spring and a shock absorber unit (109) connected to the chassis frame structure. A hydraulic braking system is attached to the front wheel (104) and said pair of rear wheels (107). A hood (101) connects a top portion of the front cowl (105) and a top portion of the body panel (110). Referring to one embodiment of the present invention, a pair of headlamp assemblies (112L), (112R) including a left headlamp assembly (112L) and a right headlamp assembly (112R) (not shown) is disposed on at least a portion of the front cowl (105) of the vehicle (100).

[00022] Figure 2 illustrates the partial rear perspective view of the vehicle (100) with few parts excluded for clarity. The frame assembly of the vehicle (100) includes a head tube (201) and a main tube (210) extending rearward from the head tube (201) & the head tube is co-axially disposed centrally on the steering axis of the vehicle such that the steering axis is disposed co-axially along the longitudinal front wheel central plane Y-Y\ The front cowl (105) is positioned in the anterior portion of the head tube (201). The frame assembly (F) includes at least one center rail (208). As per present subject matter the vehicle (100) has brake assembly which includes a center brake line assembly (206), a front brake line assembly (203), a rear brake line assembly (202) and a proportionating device (204). The proportionating device (204) is functionally connected to the center brake lines assembly (206) and tandem master cylinder (211) using brake line nuts (301) (as shown in fig. 3). The center brake line assembly (206) is connected to a rear brake line assembly (202) at one of its ends. The center brake line assembly (206) connected to the rear brake line assembly (202) using at least one T-joint (205). The rear brake line assembly (202) includes at least two brake lines (202a, 202b) functionally connected to the pair of a rear wheels (107) (as shown in fig. 1) respectively. The center brake line assembly (206) includes at least one center brake line (206a), wherein said center brake line (206a) configured to have a S- bend (207) disposed in the driver compartment of the vehicle. The center brake line assembly (206) is enclosed within the channel of the center rail (208). The S- bend (207) enables the connection of center brake line (206a) to the proportionating device (204). The S- bend (207) is partially enclosed within the channel space in the center rail (208). Further, the center brake line (206a) follows the straight path which avoids plurality of bends which leads to less fluid resistance and less reaction time in the rear brake circuit as compare to conventional brake circuits. Moreover, it results in less amount of fluid required due to reduced length of the center brake line which further reduces the size of the master reservoir thereby enhancing the response time of the brake system & its efficiency. Additionally, less weight and reduced length leads to material saving and cost reduction.

[00023] Figure 3(a) and 3(b) illustrates the top sectional view and the rear side cut section view across Z-Z’ axis of the vehicle (100) respectively as per preferred embodiment of the vehicle (100) where few parts are omitted from the figure. As shown in fig. 3(b) the center rail (208) comprises of a channel member which has an interior bounded by a vertical side walls (208b) and by horizontal top wall (208a) and bottom wall (208c) which extend from top and bottom of the vertical walls (208b) toward the top and bottom portion of a cross member (302) wherein the cross member (302) is extending in lateral direction (LL’) of the vehicle (100), and other end is connected to the portion of main tube (210) of said frame assembly (F). Further, as shown in fig. 3(a) the proportionating device (204) is disposed between imaginary plane B-B’ and imaginary plane C-C\ The imaginary plane C-C’ is passes through the center of the center rail (208) in longitudinal direction (YY) of the vehicle (100). The imaginary plane B-B’ is substantially parallel to the imaginary plane C-C’ such that imaginary plane B-B’ is at a predetermined distance (Dra) from the imaginary plane C-C’. The predetermined distance (Dla, Dra) ranges from 5 millimeter to 100 millimeter. The one end of said proportionating device (204) functionally engages to at least one end of a center brake line assembly (206) and another end of said proportionating device (204) functionally engages with at least one end of the tandem master cylinder (211) (as shown in figure 2). As per preferred embodiment the proportionating device (204) is provided in vicinity of the brake pedal (209) i.e. right-hand side of the vehicle (100) when viewed from the rear of the vehicle (100). As per alternative embodiment, the proportionating device (204) is located in between the plane A-A’ and imaginary plane C-C’. The imaginary plane A-A’ is substantially parallel to the imaginary plane C-C’. The plane A-A’ is having predetermined distance (Dla) from the imaginary plane C-C’. The predetermined distance (Dla) ranges from 5 millimeter to 100 millimeter. As per an aspect of the present invention, the proportionating device (204) may at least partially overlap with any of the 3 planes viz. A’ A’, B-B’ or C’C’. [00024] Thus, as per present subject matter the proportionating device (204) is located in optimum location between the imaginary planes and ahead of seat assembly (111) such that it is coming within best conical & ergonomic view of the operator during driving condition. Further, if proportionating device (204) is located outside this predetermined range, the fluid resistance is increased due to presence of plurality of bends which further increases the length of the center brake line assembly (206). While such disposition provides more flexibility of design & layout packaging for the design engineer, this increased length of the brake line adversely increases the volume of fluid required for braking operation. Moreover, the increased length of the brake line necessitates complete redesign of the center rail (208) which typically includes increase in the length of the center rail (208) in lateral direction (LL’) of the vehicle (100). Therefore, all above factors increase the response time of braking operation which reduces the efficiency of the braking system of the vehicle (100) while additionally deteriorating the comfort, ergonomics & convenience of the braking system.

[00025] Figure 4(a) and Fig 4(b) illustrates the side view and top view of the vehicle (100) respectively it is very critical for a designer to mount and locate the proportionating device such that it should come within best conical view without compromising on the brake efficiency. As the brake pedal (209) is frequently used by the operator during driving condition therefore as per the present subject matter, it is positioned ergonomically & in a cone of sight for ease of vision the proportionating device (204) as per the present invention is disposed in close proximity of the brake pedal (209) so that any leakage can be easily identified which is generally unnoticeable during driving condition. As shown in fig. 4(a) the vertical plane eye movement (cone of sight) where eye can rotate maximum downward direction (Md) without head movement from the line of sight (Ls) is in the angle Oa i.e. 65 degrees downward. Thus, the proportionating device (204) is disposed such that at least a portion of the proportionating device (204) falls within the line of sight (Ls) and maximum downward direction (M d ) without any significant head movement. This configuration avoids any undesirable movement of the head or distraction to change the cone of sight to view or visibly detect any signs of leakage while the user is driving the vehicle. Further, fig. 4(b) illustrates the binocular view field in the horizontal direction where the best conical view i.e. acceptable eye rotation is coming within the imaginary plane A-A’ and imaginary plane B-B\ This acceptable eye rotation is generally 30 degrees from the line of sight (Ls) in horizontal plane. Thus, the proportionating device (204) is configured in the ergonomic conical cum binocular locus of sight without necessitating any head movement while at same time not making any compromise on the braking efficiency and at same time being compact in packaging as well as cost effective. The optimum location between imaginary plane B-B’ and C-C’ as preferred embodiment avoids the poor visibility conditions which is stressful for an operator during driving condition and significantly increases risk of accident because of unattended leakage. Thus, the present subject matter ensures that the operator can clearly see slightest of leakage in proportionating device and high-pressure center line fittings if any and can anticipate and prepare for avoiding any accident.

[00026] Figure 5 illustrates the graphical representation comparing conventional braking system and the proposed braking system. The x-axis represents input load (Newton) on the brake pedal (209) and y-axis represents output pressure (bar) at the wheel brakes. Typically, ideal brake force distribution curve (A) is a quadratic curve which results in the maximum decelerations and minimum stopping distances. It is developed based on the dynamic weight transfer between the front axle and rear axle during deceleration of the vehicle (100). The figure 5(a) illustrates the graphical representation of ideal brake performance (A) versus actual brake performance (B) for a conventional braking system, indicating wheel locking conditions. The actual braking curve (B) is a linear curve passing through the origin. During higher decelerations both curves intersect at a point (I) where both front wheel (104) (as shown in fig. 1) and rear wheels (107) (as shown in fig. 1) lock at the same time. Further, any increase in input load on the brake pedal (209) results in the locking of rear wheels (107) ahead of front wheel (104) (owing to load transfer effect), which is dangerous as the driver loses control over the vehicle (100).

[00027] Figure 5(b) represents the graphical representation of ideal brake performance (A) versus actual brake performance (B’) for a proposed braking system. In order to avoid or eliminate the rear wheels (107) locking, the braking system configured to have the proportionating device (204) disposed in an optimum locus or region (vertical cone of sight cum binocular lateral cone of sight) which reduces the fluid resistance and regulates the rear brake circuit pressure to avoid locking of the rear wheels (107). As a result of the present configuration of the braking system, the intersection point (G) between the idle curve (A) and actual braking curve (B’) is shifted. This is because firstly the rear wheel locking deceleration is determined and the proportionating device (204) is designed and configured in a region or locus such that just before rear wheels (107) lock the pressure to the rear circuit is reduced to a ratio based on the ideal curve (A).

[00028] Thus, as per present subject matter the center brake line connected to the respective brake lines i.e. front brake line and rear brake line are formed of the metal pipes that are disposed in the center rail, & the center brake line is disposed not to be viewed from the external side. Accordingly, the external appearance is also improved. Further, the center brake line assembly is designed to follow straight line longitudinal path which reduces the fluid resistance and length of brake line, as lengths of the paths of the center brake lines formed of the metal decreases which further reduces the cost and weight of the brake assembly.

[00029] In addition, since the proportionating device is disposed behind the head pipe & is having a closer distance to the front wheel brake and the front brake pipe extends frontward after passing through hole in chassis frame structure, therefore the length of the front brake line extending to the front wheel brake is reduced by reducing the lengths of the brake line connecting proportionating device to the tandem master cylinder. Thus, the lengths of the paths of the front brake lines (typically formed of metal) decreases and thus the adverse liquid loss caused by expansion of lines is suppressed. This improves the response efficiency of the system as well as the reliability.

[00030] Moreover, the center brake line is routed through a front side of the center member of frame assembly to connect with the proportionating device which is arranged in an upward direction ahead of seat assembly and between imaginary plane B-B’ and plane C-C’ in the vicinity of the brake pedal as per preferred embodiment. however as per alternative embodiment the proportionating device is configured ahead of seat assembly and located between imaginary plane A- A’ and C-C\ Thus, proportionating device is easily serviceable without need of jack or external means as there is no need to lift the vehicle thereby improving the serviceability & maintainability of the vehicle.

[00031] Furthermore, the proportionating device is connected to the center brake line and front brake line through tandem master cylinder such that no external support is required to support the proportionating device. Thus, plurality of brackets required to support the proportionating device is eliminated which reduces the manufacturing cost including assembly time, material cost, weight etc. and service time to disassemble and assemble the proportionating device.

[00032] Further, the present subject matter avoids the accidents due to leakage in proportionating device, because it is externally visible to the operator as located ergonomically in pre-determined locus or region & close proximity of the brake pedal coming within best conical view 3 -dimensional ergonomic vision of the operator. In addition, as per alternative embodiment, the leakage is easily visible externally, since the proportionating device is located ergonomically in the vicinity of the main tube and coming within best conical view of the driver. As per the brake system layout of the present invention, the configuration described above offers multiple advantages viz. minimizing brake line lengths, improving response time by minimizing brake fluid quantity as well as line friction losses, avoiding brake locking by extending the locking load point, enhancing safety through ease of leak detection while riding, minimizing numbers of component, reducing cost, improving ease of service, better efficiency of braking as well as higher reliability all of which is collectively achieved with the configuration outlined in above paragraphs. Known arts tends to provide solutions to few of the above while compromising one some of them which is undesirable.

[00033] While the present invention has been shown and described with reference to the foregoing preferred embodiments, it will be apparent to those skilled in the art that changes in form, connection, and detail may be made therein without departing from the spirit and scope of the invention. List of references:

Longitudinal axis (YY’)

Lateral axis (LL’)

Upward direction (Up)

Downward direction (Dw)

Frame assembly (F)

Ideal brake curve (A)

Actual brake curve for conventional braking system (B) Intersection point for conventional braking curve (I) Actual brake curve for proposed braking system (B’) Intersection point for proposed braking system (F) Imaginary plane (A-A’)

Imaginary plane (B-B’)

Imaginary plane (C-C’)

Reference axis (Z-Z’)

Predetermined distance (Dla, Dra)

Angle (Oa)

Vehicle (100)

Divided into two compartments along the line (X-X’) Driver/user compartment (D)

Passenger compartment (P)

Front portion (F)

Rear portion (R)

Line of sight (Ls)

Maximum downward direction (Md) Hood (101)

Windscreen (102)

Wheel cover (103)

Front wheel (104)

Front cowl (105)

Rear cabin (106)

Pair of rear wheels (107)

Floorboard (108)

Shock absorber unit (109)

Body panel (110)

Seat assembly (111)

Pair of headlamp assemblies (112L), (112R) Passenger seat assembly (113)

Handle bar assembly (114)

Head tube (201)

Rear brake line assembly (202)

Left rear brake line (202b)

Right rear brake line (202a)

Front brake line assembly (203) Proportionating device (204)

T-joint (205)

Center brake line assembly (206)

Center brake line (206a)

S- bend (207)

Center rail (208) Brake pedal (209)

Main tube (210)

Tandem master cylinder (211) Brake line nuts (301) Cross member (302)