FORM 2
THE Patent Act, 1970
(39 of 1970)
&
The Patent Rules, 2003
COMPLETE SPECIFICATION
(See Section 10 and Rule 13)
Combined brake system for a two wheeler
Endurance Technologies Limited R&D, E 93, MIDC Industrial Area, Waluj, Aurangabad, Maharashtra-431136
The following specification describes the invention

Field of the invention
The present invention relates to combined brake system for a two wheeler. More specifically, the present invention relates to combined delay valve and master cylinder arrangement for two wheeler combined braking system.
Description of the prior art
The term "combined brake system" in connection with motorcycle or a two wheeler is understood to mean a brake system in which, when a "hand brake lever" or the "foot brake pedal" is operated, the front wheel brake and the rear wheel brake are applied. Thus, by operating a single actuating device, both brakes are applied. Combinations are also possible wherein one brake lever acts on one wheel and the other brake pedal on both wheels.
One combined brake system for motorcycles is disclosed, for example, in DE3803563 A1. In this brake system, when the foot brake pedal is operated, braking pressure is applied simultaneously to the front wheel brake and the rear wheel brake. Furthermore, an additional front wheel brake is provided to which braking pressure is applied by operating the hand brake lever. The additional front wheel brake can be operated independently of the operation of the foot brake lever. When in combination mode, rear pedal is operated, an additional change in the wheel loading takes place due to simultaneous operation on front wheels. In order to prevent the front wheel from locking up when the foot lever is operated, a brake pressure regulator is provided which accordingly limits the pressure at the front brake.
A master cylinder assembly is used to generate hydraulic pressure for actuation of all the brakes located within the wheels of a two wheeler. The master cylinder is operated by means of effort of a rider by compression of a piston in it. In order to provide pressure difference in two different

chambers, a delay valve is generally included in the hydraulic line so as to limit the pressure increase till the other circuit's pressure exceeds a certain valve.
However, in the current art, the delay valve and master cylinder are placed separately in the vehicle. Thereby, two separate mounting brackets are required, one for mounting the master cylinder assembly and other for mounting the delay valve assembly. Both of which are present separately on the vehicular chassis. Thus, leading to increased number of parts,
Also, a separate hose or tube is required to connect the master cylinder assembly with the delay valve assembly due to which loss of efficiency occurs.
Furthermore, the master cylinder assembly, in the current state of art comprises of one pressure inlet port and two pressure outlet port. One pressure outlet port supplies the breaking force to the rear wheel of the vehicle through the hydraulic line directly. Whereas, the other pressure outlet port supplies the breaking force to the front wheel of the vehicle through the hydraulic lines going through the delay valve assembly. The delay valve assembly also comprises of one pressure inlet port and one pressure outlet port. The pressure outlet port of the delay valve assembly then supplies the braking force to the front wheel of the vehicle through the hydraulic line.
Apart from this, certain models have an additional component called as junction box. The junction box is also mounted separately on the vehicular chassis. The junction box is connected to the master cylinder pressure outlet port by a hose/tube. Through the junction box one pressure outlet port goes to the rear wheel of the vehicle through the hydraulic line directly. While the other pressure outlet port goes to the delay valve assembly which thereafter supplies braking force to the front wheel of the vehicle through hydraulic line with a proportionate delay.

Hence, to obviate the lacunae of the prior art, the main objective of the present invention is to provide a combined delay valve and master cylinder arrangement.
It is therefore an object of the present invention to provide a combined delay valve cum master cylinder assembly to be called as delay cum master cylinder arrangement in two wheeler for combined braking system. The delay cum master cylinder arrangement would be mounted as a single piece unit. Thereby eliminating the need for different mounting brackets for mounting the master cylinder arrangement, delay valve arrangement and junction box separately on the vehicular chassis.
It is yet another object of the present invention is to provide an arrangement that would be simple in construction as the said delay cum master cylinder would be mounted on a single bracket on the vehicular chassis.
Additionally, the said delay cum master cylinder would only have three supply ports. One pressure inlet port and two pressure outlet port. Thereby comparatively reducing the number of supply ports required in accordance with the prior art. Thus, allowing reduction in assembling man-hours.
It is yet another aspect of the present invention is to. provide an arrangement with increased efficiency as there would be no hose/tube for connection from one arrangement to another.
It is yet another aspect of the present invention is to provide an arrangement that would reduce the overall weight of the vehicle.
It is yet another aspect of the present invention is to provide a low cost and equally efficient combined delay valve and master cylinder.

Summary of the invention
In accordance with the present invention, there is provided a combined master cylinder assembly and the delay valve in one single piece unit to be called as delay cum master cylinder assembly including:
A hydraulic drum or hydraulic disc front wheel brake that can apply braking force to the front wheel;
A hydraulic drum or disc rear wheel brake that can apply braking force to the rear wheel;
A hydraulic line from each pressure outlet port of delay cum master cylinder arrangement;
A brake pedal that is coupled with a pedal arm which in turn is clamped with a lever to the delay cum master cylinder piston.
An oil reservoir coupled with a delay cum master cylinder arrangement suitable mounted.
The delay cum master cylinder arrangement for combined brake system for two wheeler wherein the said arrangement comprises of two pressure outlet port and one pressure inlet port; The said arrangement comprises of an upper segment and a lower segment. The said upper segment is coupled with the said lower segment by a common carrier.
The upper segment essentially comprises of elements of master cylinder assembly while the said lower segment essentially comprises of elements of delay valve assembly.
The said hydraulic line supplying the braking force to the rear wheel of the vehicle instantly whereas the other hydraulic line supplying the braking force to the front wheel of the vehicle with a delay.

On actuation of the brake pedal, pedal arm lever coupled axially pushes the delay cum master cylinder piston. The pressure outlet port is connected with hydraulic lines which transfers the pressure to the front wheel as well as the rear wheel. One pressure outlet port which is in continuation with the common carrier supplies the pressure to the rear wheel. This braking pressure is transferred instantaneously. On the other hand the pressure through the other pressure outlet port connected with the front wheel the said braking force is transferred with a fraction of delay. Thereby allowing a proportionate lag between supplying of braking force on both the wheels.
The said delay cum master cylinder assembly is placed at a suitable location on the vehicular body. The said upper segment and lower segment are oriented in a suitable orientation with respect to each other.
The delay cum master cylinder is mounted over the vehicular body at a suitable mounting bracket.
Brief description of the invention
Fig. 1(a) is a cross-sectional view of the rear Master Cylinder Assembly in a combined brake system for two wheeler as according to the prior art.
Fig. 1(b) is an exploded view of the rear Master Cylinder Assembly in combined a brake system for two wheeler as according to the prior art.
Fig. 2(a) is a cross-sectional view of the Delay Valve Assembly in a combined brake system for two wheeler as according to the prior art.
Fig. 2(a) is an exploded view of the Delay Valve Assembly in a combined brake system for two wheeler as according to the prior art.

Fig. 3(a) is a cross-sectional view of the Delay cum Master Cylinder arrangement in combined brake system for two wheeler as according to the present invention.
Fig. 3(b) is an exploded view of the Delay cum Master Cylinder arrangement in combined brake system for two wheeler as according to the present invention.
Fig. 4 is a 3D view of the delay cum master cylinder arrangement as according to the present invention.
Fig. 5 is the cross-sectional view of the Delay cum Master Cylinder arrangement coupled with brake pad and pedal arm in combined brake system for two wheeler as according to the present invention.
Fig. 6 is the cross-sectional view of the Delay cum Master Cylinder Assembly installed on the two wheeler having combined brake system as according to the present invention
Detailed description of the invention
Hereinafter, an embodiment of delay cum master cylinder assembly for combined brake system in two wheeler according to the present invention will be described with reference to the drawings.
Fig 1(a) and Fig. 1(b) are cross-sectional and exploded view of a conventional rear Master Cylinder Assembly (120a) and (120b) in combined brake system for two wheeler respectively. A conventional master cylinder assembly (120a and 120b) is suitably mounted on the vehicular chassis through the mounting brackets (123). The master cylinder assembly essentially comprises a piston return spring (124), master cylinder piston (125), a push rod (126), a protection boot (127) and a push rod fork (128). The said components are configured to contain within the of the master

cylinder body (122). At the head of the master cylinder assembly is the oil filler (121) which is connected with the oil reservoir. The oil reservoir may be placed either internally along with the master cylinder assembly or at a suitable position on the vehicular body.
Fig 2(a) and Fig. 2(b) are cross-sectional and exploded view of the Delay valve assembly (140a and 140b) in combined brake system for two wheeler respectively. A conventional delay valve (140a and 140b) assembly is suitably mounted on the vehicular chassis through a separate mounting bracket. The delay valve assembly essentially comprises of a main piston (142), a main spring (143), a secondary spring (144), a fixed piston (145) and a delay valve cover (146) configured to contain within the delay valve body (141).
According to one embodiment of the present invention as illustrated in Fig. 3(a) and Fig. 3(b) are cross-sectional and exploded view of the Delay cum Master cylinder arrangement (220a and 220b) in combined brake system for two wheeler respectively. Herein, the upper segment is coupled with a lower segment by a common carrier (255ab). The upper segment (222a) of the delay cum master cylinder assembly essentially comprises a piston return spring (224a), master cylinder piston (225a), a push rod (226a), a protection boot (227a) and a push rod fork (228a) are configured to contain within. At the head of the delay cum master cylinder assembly is an oil filler (221a) that is connected with an oil reservoir (10). The lower chamber (221b) of the delay cum master cylinder assembly essentially comprises a main piston (222b), a main spring (223b), a secondary spring (224b), a fixed piston (225b) and a delay valve cover (226b) configured to contain within. The delay cum master cylinder arrangement (220a) has two pressure outlet ports (244) and (245). These pressure outlet ports are connected by the hydraulic lines (7) and (8) which carry the braking force to the front and the rear wheel.

Fig.4 is the 3D view of delay cum master cylinder which represents the two pressure outlet ports (245) and (245). The pressure outlet port (244) is in continuation with the hydraulic line (8) which supplies the braking force to the rear wheel (2) on the other hand the pressure outlet port (245) is in continuation with the hydraulic line (7) which supplies breaking force to the front wheel (1).
According to another embodiment of the present invention referring to Fig. 5 which represents the cross-sectional view of the delay cum master cylinder arrangement (220a) wherein it is clamped with the pedal arm (12) through lever (13). On actuation of brake pedal (11) the master cylinder piston (228a) moves axially within the upper chamber (222a) from where the braking force is transmitted to the rear wheel (2) and front wheer(l).

According to yet another embodiment of the present invention referring to fig. 5 and fig. 3(a) wherein on actuation of the brake pads (11) which is coupled with the pedal arms (12) the delay cum master cylinder piston (228a) is pushed axially into the upper chamber (222a). The upper chamber (222a) of the delay cum master cylinder (220a) is coupled with a common carrier (255ab). The said common carrier (255ab) is in continuation with one pressure outlet port (244) which supplies the braking force through one hydraulic line (8) to the rear wheel of the vehicle. This supply of the braking force in combined brake system for two wheeler occurs instantaneously. On the other hand on actuation of the brake pads (11) which is coupled with the pedal arms (12) the delay cum master cylinder piston (228a) is pushed axially into the upper chamber (222a). This converts the mechanical energy into pressure energy. Thus generated pressure passes through the lower chamber (221b) of the delay cum master cylinder assembly (220a). The lower chamber (221b) is coupled with the second supply port (245) which is in continuation with the hydraulic line (7) which carries the braking force to the front wheel (1) of the vehicle. The braking force is transmitted to the front wheel (1) with a fraction of delay.

On referring to yet another embodiment of the present invention illustrated in fig. 6 wherein the front wheel (1) has a conventional design, i.e., a three pot brake caliper (5) of the disk brake (3) which is connected by a hydraulic line (7) to the delay cum master cylinder assembly (220a) which is controlled with a hand brake lever (8).
As illustrated in Fig. 7, till the knee point, delay valve will allow pressure generation in the rear brake system. After knee point, front brake circuit pressure increases with rear brake circuit pressure and after a certain point, both the pressures match.
It will be appreciated form the foregoing description that various other embodiments of the above mentioned device are possible without departing from the scope and ambit of this invention.

Claims
We Claim:-
1. A combined brake system for a two wheeler with a delay cum master cylinder arrangement
comprising:
a hydraulic drum or hydraulic disc front wheel brake for applying braking force to a front wheel;
a hydraulic drum or hydraulic disc rear wheel brake for applying braking force to a rear
wheel;
a brake pedal supported on said two wheeler body that includes a pedal arm;
a hydraulic line extending to rear wheel and front wheel of said two wheeler;
a hand brake lever connected to the hydraulic drum or hydraulic disc of the front wheel;
and an oil reservoir suitably mounted on said two wheeler body and coupled with said
delay cup master cylinder arrangement, wherein a master cylinder and a delay valve
are combined in a single unit and mounted at a suitable location on said two wheeler.
2. The combined brake system for a two wheeler as claimed in claim 1, wherein said delay cum master cylinder comprises an upper segment and a lower segment, said upper segment has components of a master cylinder assembly and said lower segment has components of delay valve assembly.
3. The combined brake system for a two wheeler as claimed in claim 1, wherein said upper segment and said lower segment are coupled by a common carrier.
4. The combined brake system for a two wheeler as claimed in claim 1, wherein at least one pressure outlet port and one pressure inlet port is provided.

5. The combined brake system for a two wheeler as claimed in claim 1, wherein supply ports provided from which the hydraulic line extends to the rear wheel and to the front wheel.
6. The combined brake system for a two wheeler as claimed in claim 1, wherein the hydraulic line extending from one pressure supply port to the front wheel supplies the braking force to the front wheel with delay.
7. The combined brake system for a two wheeler as claimed in claim 1, wherein the hydraulic line extending from one pressure supply port to the rear wheel supplies the braking force to the rear wheel instantaneously.
8. The delay cum master cylinder as claimed in claim 1 and claim 8, wherein the supply port for rear wheel is coupled with the common carrier.
9. A motorcycle with a delay cum master cylinder as claimed in claim 1.