DESC:FORM 2
The Patent Act 1970
(39 of 1970)
&
The Patent Rules, 2005

COMPLETE SPECIFICATION
(See Section 10 and Rule 13)

TITLE OF THE INVENTION
“COMBINED BRAKE ACTUATION SYSTEM FOR A VEHICLE”

Endurance Technologies Limited
E-92, M.I.D.C. Industrial Area, Waluj,
Aurangabad – 431136, Maharashtra, India

The following specification particularly describes and ascertains the nature of the invention and the manner in which it is to be performed.

Field of Invention

[001] The present invention is related to braking system for a vehicle. More particularly, the invention is related to brake actuation system for two wheeled motor vehicles, preferably bikes and scooters, wherein the brake actuating system has a floating type master cylinder assembly which has more stability in vehicle fitment and allows delay time between actuation of front and rear brakes to be easily adjusted.

Background of the Invention

[002] Conventional combined brake actuating system require mounting points on vehicle frame for stably mounting them on the vehicle frame. It is not always possible to provide these mounting points on the vehicle body/frame (or a bracket attached to the vehicle frame) as more and more features are added to the motor vehicle’s body. Ordinarily this problem of absence of space for providing mounting points is solved by utilizing combined brake actuating system with a master cylinder assembly that can float when assembled onto the motor vehicle. Master cylinder assembly of such a combined brake actuating system are normally located coaxially on a brake actuating rod. The master cylinder assembly so provided, have their degree of freedom further restricted by a link movably attaching it to the brake pedal or the motor vehicle frame/body along one pivot point that is suitably located on the master cylinder assembly itself. A common deficiency of such combined brake actuating system is that the master cylinder assembly provided in them are not stably fitted on the motor vehicle body and can get damaged by vibrations during ordinary operation of the motor vehicle. They are hence less durable and reliable in comparison to conventional combined brake actuating system that are mounted on motor vehicle body/frame. Furthermore, given the lack of fitment stability, adjusting the delay between actuation of front and rear wheel brakes becomes even more challenging in such combined brake actuating system. This makes it very hard for the assembly technician to adjust the braking characteristics of the combined braking system. Therefore, there exists a need for a durable and reliable combined brake actuating system that can be provided in motor vehicles having very little mounting space for assembling them onto a motor vehicle.

Objectives of the Invention

[003] The main object of the present invention is to provide a combined brake actuating system that can be stably assembled onto a motor vehicle having very little mounting space.

[004] Another object of the present invention is to provide a combined brake actuating system for vehicles wherein the master cylinder assembly of the system is floating.

[005] Still another object of the present invention is to provide a combined brake actuating system for motor vehicles wherein the master cylinder assembly is stably held on the motor vehicle so as to improve its durability and reliability in ordinary operating conditions.

[006] It is yet another objective of the invention to provide a combined brake actuating system that provides the superior braking performance while maintaining the quality of braking as well and keeping the cost of production low.
[007] It is still another objective of the invention to provide a combined brake actuating system with a provision for easily adjusting the braking characteristics so that the end user can drive the vehicle with enhanced comfort and safety.

Brief Description of the Drawings

[008] This invention is illustrated in the accompanying drawings, throughout which like reference letters indicate corresponding parts in the various figures. The embodiments herein and advantages thereof will be better understood from the following description when read with reference to the following drawings, wherein

[009] Figure 1 discloses vehicle level pictorial view of combined brake actuating system in accordance with the present invention.

[0010] Figure 2 shows an isometric view of the combined brake actuating system in accordance with the present invention in its non-operative condition.

[0011] Figure 3 shows the sectional view of the combined brake actuating system as per the present invention.

[0012] Figure 4 shows an exploded view of the combined brake actuating system in accordance with the preferred embodiment of the present invention.

[0013] Figure 5 shows an isometric view of the combined brake actuating system in accordance with the present invention in its operative condition.
[0014] Figure 6 shows an isometric view of the combined brake actuating system in accordance with the present invention as mounted at attachment points given on the motor vehicle.

Detailed Description of the Present Invention

[0015] Referring to Fig. 1, the combined brake actuation system (1000) for a motor vehicle in accordance with the present invention comprises of a master cylinder assembly (100), a piston operating lever (110), a slotted link (120), a drum brake operating link (130), a drum brake (140), an actuator (150), an anti-rotation arm (160), a brake pedal (170), a brake fluid reservoir (180), a hydraulic line (190) and a front wheel hydraulic brake (200).

[0016] The brake pedal (170) is mounted onto the motor vehicle at a pivoting point (P1) that is located on the motor vehicle body (refer Figs. 1, 3 and 6). One arm (170A) of the brake pedal (170) functions to accept and transmit the user applied force to a second arm (170B) across the pivoting point (P1). The second arm of the brake pedal (170) is rotatably linked to the connector (151) at a point (C3). The connector (151) is in turn rotatably connected to the actuator (150) at a point (P2). The actuator (150) has a body with three arms (150A, 150B and 150C). One arm (150A) is rotatably linked to the connector (151) at a point (C3). The second arm (150B) of the actuator (150) is linked to a curved arm (10A) that projects upwards from the top portion of above a housing body (10) of the master cylinder assembly (100) at a point (P3) that is provided on the lower portion of the curved arm (10A) and also at a point (P6) that is located on the end of said curved arm (10A). The third arm (150C) of the actuator (150) is linked to a delay spring (210) at a point (C1) and the third arm (150C) is also linked to another arm (10C) extending below the housing body (10) of the master cylinder assembly (100) at its end at another point (P13).

[0017] The anti-rotation arm (160) is rotatably linked to the actuator (150) at a point (P4) that is located at the confluence point of the three arms (150A, 150B and 150C) of the actuator (150), the anti-rotation arm (160) is further rotatably attached to the motor vehicle body at a point (P5) and hence the anti-rotation arm (160) restricts the degree of freedom of the actuator (150).

[0018] The piston operating lever (110) is rotatably connected to the curved arm (10A) at the point (P6) that is located on the end of said curved arm (10A). A central portion of said piston operating lever (110) rests on an outward projecting portion of the piston (15P) of the piston assembly (15), the other end of the piston operating lever (110) is rotatably linked to the slotted link (120) at a point (P7). The housing body (10) has another arm (10C) projecting downwards from its lower portion which movably supports the slotted link (120) at two points (P8 and P9). The slotted link (120) is connected to the drum brake operating link (130) at its one end at a point (P10). The lever (140A) of the drum brake (140) is connected to the other end of the drum brake operating link (130) at a point (P11). The links so establish allow the lever (140A) to rotate along a point (P12) located on the drum brake (140) under action of the drum brake operating link (130) thereby causing the application of the drum brake (140). The delay spring (210) is linked at its one end to the slotted link (120) at a point (C2) located below the plane in which the points (P7, P8 and P9) are provided, the other end of the delay spring (210) is linked to the end of the third arm (150C) of the actuator (150) at the point (C1).
[0019] The housing body (10) of the master cylinder assembly (100) has a bore (10B) within which a delay spring (220), a piston assembly (15), an oil seal(s) (1SA), a circlip (1C) and a dust seal (1SB) are assembled in the given order. One end of the delay spring (220) is supported at the closed end of the bore (10B). The delay spring (220) is therefore capable of supporting the piston assembly (15) that is positioned in direct contact with the other end the delay spring (220). The central portion of said piston operating lever (110) rests on an outward projecting portion of the piston (15P) of the piston assembly (15). The master cylinder assembly (100) is connected to a brake fluid reservoir (180) through a port (95) given on the top of a housing body (10) by a hydraulic line (95L).

[0020] The master cylinder assembly (100) is also hydraulically linked by a hydraulic line (190) to the front wheel hydraulic brake (200) at a port (90) given alongside the port (95) on the top of the housing body (10). The port (95) opens into the bore (10B) with the chamber formed in front of the piston (15P) of the piston assembly (15) remaining in hydraulic connection with the brake fluid reservoir (180) when the brake pedal (150) is not being operated. The port (90) also opens into the bore (10B) thereby maintaining a hydraulic connection between with the chamber formed behind the piston (15P) of the piston assembly (15) and the hydraulic line (190) linked with the front wheel hydraulic brake (200) (refer Figure 3).

[0021] The point (P1) utilizes a projection provided on the vehicle body and locking clips or other suitable fastening arrangement to allow limited rotational movement along the axis of the projection and prevent any movement up and down along its axis. A torsion spring may also be accommodated at the point (P1) with its one end fixed on the brake pedal (170) and the other end fixed on the vehicle body. Such arrangement allows the brake pedal (170) to be restored to its original position after the user has stopped applying force on its one arm (170A). The points (P2 and C3) utilize sliding pins that are fixed in the holes given the legs of the U-shaped ends of the connector (151) to permit rotational movement along there axis and prevent movement up and down there axis. The points (C1 and C2) are openings provided in the actuator (150) and the slotted link (120) respectively that allow ends of the delay spring (210) to be fixed within them. The points (P4, P5, P6, P7, P8, and P9) utilize a combination of sliding pins (3P), washers (3W) and locking clips (3LC) to prevent movement up and down there axis while permitting rotational movement along there axis (refer Figs. 2 and 4). The points (P3, P10 and P13) utilize a combination of bolts (3B) and nuts (3N) to firmly link there associated parts and prevent any relative movement between them (refer Figs. 2 and 4).

[0022] The non-operational state of the combined brake actuation system (1000), i.e. when no force is being applied by the vehicle user on the one arm (170A) of the brake pedal (170) is observable in Figure 2. When the vehicle user begins operating the brake pedal (170) by applying force on the one arm (170A), the connecting link (151) (which is connected to both the brake pedal (170) and the actuator (150)) pulls the actuator (150) thereby causing it to move forward and also rotate with respect to the anti-rotation arm (160) with the point (P5) forming the axis of rotation. The forward movement of the actuator (150) pulls the master cylinder assembly (100) ahead with itself. This happens because the actuator (150) itself is linked to the housing body (10) of the master cylinder assembly (100) on the arms (10A and 10C) at points (P3, P6 and P13) respectively. The piston operating lever (110) connected to housing body (10) of the master cylinder assembly (100) at point (P6) and the slotted link (120) at point (P7) also moves forward. As the slotted link (120) is connected to the drum brake operating link (130) at the point (P10), forward movement of the slotted link (120) is also transmitted the lever (140A) located on the drum brake (140) by the drum brake operating link (130). The lever (140A) located on the drum brake (140) therefore rotates and begins application of the drum brake (140). As soon as the drum brake’s application begins, a reaction force transmitted from the lever (140A) located on the drum brake (140) to the piston operating lever (110) via the drum brake operating link (130) and the slotted link (120). This reaction force causes the piston operating lever (110) to begin pressing upon the projecting portion of the piston (15P) positioned in the bore (10B) of the housing body (10) of the master cylinder assembly (100). This causes hydraulic fluid to be displaced from the housing body to the front wheel hydraulic brake (190) via the hydraulic line (200) linking the housing body (10) of the master cylinder assembly (100) to the front wheel hydraulic brake (200).

[0023] As the operation of the brake pedal (170) progresses further and more force is applied by the motor vehicle operator on the arm (170A) of the brake pedal (170), at first the drum brake (140) is more firmly applied. The reaction force transmitted back from the drum brake (140) via the lever (140A), the drum brake operating link (130), and then the slotted link (120) then in turn causes the piston operating lever (110) to further displace the piston (15P) inside the bore (10B) of the housing body (10) (refer Fig. 5 and observe that the piston (15P) has been pushed into the bore (10B) of the housing body (10) in the operating condition). This in turn causes more hydraulic fluid to be displaced from the housing body (10) of the master cylinder assembly (100) to the front wheel hydraulic brake (200) via the hydraulic line (190), causing the application of the front wheel hydraulic brakes (200) even more firmly. The delay spring (220) positioned between the piston (15P) and the housing body (10), and the delay spring (210) located between the slotted link (120) and the actuator (150) would prevent the displacement of the piston (15P) into the housing body (10) of the master cylinder (100) until the actuation of the drum brake (140) has already begun.

[0024] When the vehicle user presses the one arm (170A) of the brake pedal (170) to apply the drum brake (140) and the front wheel hydraulic brake (200), a restoring force is setup in the delay springs (210), the delay spring (220), the restoring springs provided within the drum brake (140) and the front wheel hydraulic brake (200) and the spring provided for the brake pedal (170). Therefore, when the vehicle user stops pressing the one arm (170A) of the brake pedal (170), the restoring force provided by these mentioned springs reverses all the movements that took place and restores the combined brake actuation system (1000) and hence the combined braking system to its non-operating condition as shown in Fig. 2. The front wheel hydraulic brake (200) may still continue to be in operational state (i.e. it may still continue to stop the rotation of the front wheel by applying a braking force) even after user has stopped pressing the one arm (170A) of the brake pedal (170) if said front wheel hydraulic brake (200) is still receiving hydraulic input via hydraulic line (300L) connecting said front wheel hydraulic brake (200) to the handle bar mounted master cylinder assembly (300) (refer Fig. 1).

[0025] The master cylinder assembly (100) as described is linked at multiple points (P3, P6, P8, P9 and P13) to the other sub-components, as described, which restrict its degree of freedom and impart it the capacity to resist being damaged due to vibrations transmitted to it during ordinary operation of the motor vehicle. Therefore, the construction of the combined brake actuation system (1000) for a motor vehicle as disclosed above provides the master cylinder assembly (100) with a stable fitment on the motor vehicle. That is even though the master cylinder assembly (100) is itself not directly linked to any mounting points on the vehicle body. The hydraulic lines (95L, 190) respectively linking the brake fluid reservoir (180) and the front wheel hydraulic brake (200) with the master cylinder body (10) at the ports (95 and 90) do not experience any significant loading due to the weight of the components.

[0026] The combined brake actuation system (1000) in accordance with the disclosed embodiments provides the following technical advantages:
- They allow a combined braking system to be provided on a motor vehicle where the attachment space or the number of attachment points available on the vehicle body are extremely limited and also when they are widely spaced apart.
- It allows the master cylinder assembly to float as it is itself not required to be directly attached on the vehicle body at any of the given attachment points.
- It is extremely durable and capable of resisting any possible damage that may happen due to vibrations being transmitted to it during operation of the motor vehicle.
- It is capable of stably holding the master cylinder assembly on the motor vehicle so as to improve its durability and reliability in ordinary operating conditions.
- It provides a combined brake actuating system that gives superior braking performance while also keeping the cost of production low.

[0027] The combined brake actuation system (1000) therefore overcome the limitations of the existing brake actuating systems. The internal construction of the drum brake (140) or the front wheel hydraulic brake (200) is unimportant for the purpose of determining scope of this invention as long as they are capable of being operated through the drum brake operating link (130) and the hydraulic line (190) respectively. Therefore, any change made to the drum brake (140) or the front wheel hydraulic brake (200) would not take the resulting brake actuation system outside the scope of claims of this invention as long as the combined brake actuation system (1000), as described, has been utilized without any technically significant alteration.

[0028] 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. ,CLAIMS:We Claim

1. A combined brake actuation system (1000) for a motor vehicle comprising of
• a master cylinder assembly (100),
• a piston operating lever (110),
• a slotted link (120),
• a drum brake operating link (130),
• a drum brake (140),
• an actuator (150),
• an anti-rotation arm (160),
• a brake pedal (170),
• a brake fluid reservoir (180),
• a hydraulic line (190), and
• a front wheel hydraulic brake (200),
wherein,
- the brake pedal (170) is mounted onto the motor vehicle at a pivoting point (P1) located on the motor vehicle body;
- the actuator (150) is configured to have a body with three arms (150A, 150B and 150C) extending outwards from its central portion;
- one end of the anti-rotation arm (160) is rotatably attached to the motor vehicle body at a point (P5) and the other end of the anti-rotation arm (160) is rotatably linked to the actuator (150) at a point (P4) and said point (P4) is located at the confluence point of the three arms (150A, 150B and 150C) of the actuator (150) in such way that the anti-rotation arm (160) restricts the degree of freedom of the actuator (150);
- one end of the piston operating lever (110) is rotatably connected to the curved arm (10A) at the point (P6) located on the end of said curved arm (10A) and the other end of the piston operating lever (110) is rotatably linked to the slotted link (120) at a point (P7) in such way that the central portion of said piston operating lever (110) rests on an outward projecting portion of the piston (15P) of the piston assembly (15);
- the housing body (10) has an arm (10C) projecting downwards from its lower portion and said arm (10C) movably supports the slotted link (120) at two points (P8 and P9);
- the slotted link (120) is connected to the drum brake operating link (130) at its one end at a point (P10) and other end of the drum brake operating link (130) is connected to the lower portion of the lever (140A) of the drum brake (140) at a point (P11);
- the delay spring (210) is linked at its one end to the slotted link (120) at a point (C2) located below the plane in which the points (P7, P8 and P9) are provided and the other end of the delay spring (210) is linked to the end of the third arm (150C) of the actuator (150) at the point (C1); and
- the master cylinder assembly (100) of the brake actuation system (1000) is in hydraulic communication with the front wheel hydraulic brake (200) through the hydraulic lines (190).

2. The combined brake actuation system (1000) for a motor vehicle as claimed in claim 1, wherein
- the arm (170A) of the brake pedal (170) is configured to accept the force applied by the user and transmit the applied force to a second arm (170B) across the pivoting point (P1) provided on the vehicle body;
- the other arm (170B) of the brake pedal (170) is rotatably linked to a connector (151) at a point (C3); and
- the connector (151) is in turn rotatably connected to the actuator (150) at a point (P2).

3. The combined brake actuation system (1000) for a motor vehicle as claimed in claim 2, wherein
- one arm (150A) of the actuator (150) is rotatably linked to the connector (151) at a point (C3);
- the second arm (150B) of the actuator (150) is linked to a curved arm (10A) that projects upwards from the top portion of above a housing body (10) of the master cylinder assembly (100) at a point (P3) provided on the lower portion of the curved arm (10A) and also at a point (P6) located on the end of said curved arm (10A); and
- the third arm (150C) of the actuator (150) is linked to a delay spring (210) at a point (C1) and the extreme end of the third arm (150C) is linked to the arm (10C) extending below the of the housing body (10) of the master cylinder assembly (100) at point (P13).

4. The combined brake actuation system (1000) for a motor vehicle as claimed in claim 3, wherein the lever (140A) is configured to rotate along a point (P12) located on the drum brake (140) under action of the drum brake operating link (130) thereby causing the application of the drum brake (140).

5. The combined brake actuation system (1000) for a motor vehicle as claimed in claim 4, wherein
- the housing body (10) of the master cylinder assembly (100) has a bore (10B) within which a delay spring (220), a piston assembly (15), an oil seal(s) (1SA), a circlip (1C) and a dust seal (1SB) are assembled in a given order;
- one end of the delay spring (220) is supported at the closed end of the bore (10B) making the delay spring (220) capable of supporting the piston assembly (15) positioned in direct contact with the other end the delay spring (220); and
- the central portion of the piston operating lever (110) rests on an outward projecting portion of the piston (15P) of the piston assembly (15).

6. The combined brake actuation system (1000) for a motor vehicle as claimed in claim 5, wherein
- the master cylinder assembly (100) is connected to a brake fluid reservoir (180) through a port (95) given on the top of a housing body (10) by a hydraulic line (95L) and is also hydraulically linked through the hydraulic line (190) to the front wheel hydraulic brake (200) at a port (90) given alongside the port (95) on the top of the housing body (10);
- said port (95) opens into the bore (10B) with the chamber formed in front of the piston (15P) of the piston assembly (15) remaining in hydraulic connection with the brake fluid reservoir (180) when the brake pedal (150) is not being operated; and
- the port (90) opens into the bore (10B) thereby maintaining a hydraulic connection between with the chamber formed behind the piston (15P) of the piston assembly (15) and the hydraulic line (190) linked with the front wheel hydraulic brake (200).

Dated this 9th day of May 2022

Sahastrarashmi Pund
Head – IPR
Endurance Technologies Ltd.

To,
The Controller of Patents,
The Patent Office, at Mumbai.