DESC:FIELD OF THE INVENTION
The present invention relates to combined braking system for a two wheeler. More particularly, the present invention relates to a combined braking system; with front hydraulically operated disc brake assembly and rear mechanically operated drum brake with an improved equalizer connectivity arrangement.
BACKGROUND OF THE INVENTION
In an effort to synchronize between front and rear braking system a ‘braking system’ which actuates two braking systems i.e. front and rear by different mechanisms ‘combined braking system’ has been brought out. One such unique system of ‘combined braking system’ is disclosed in the present invention which aims to provide required amount of force to the front and rear brakes.
Existing combined braking system generally incorporate various combinations of hydraulically operated disc/drum brake on front or rear wheel braking system and mechanically operated drum brake on rear or front wheel braking system.
One such prior art exists where front wheel is equipped with hydraulically operated disc brake and rear wheel is equipped with hydraulically operated drum brake with a CBS actuating means provided on foot pedal as disclosed in 3130/MUM/2015 titled “Combined brake system for a two wheeler” .
333/CHE/2013 titled “Brake device for motorcycle” discloses another prior art having hydraulically operated disc brake on the front wheel and mechanically operated drum brake on the rear wheel with CBS actuating means provided on the foot pedal. The patent connects the equalizer directly to the transmission arm of the brake pedal in a rotatable manner. There is also no arrangement in the master cylinder so as to take the side loads from the actuating pin, thereby increasing the piston wear and decreasing the life of the piston seal.
4312/CHE/2013 titled “Combined brake system for saddle-ride type vehicle” discloses another prior art having hydraulically operated disc brake on the front wheel and mechanically operated drum brake on the rear wheel with CBS actuating means provided on the foot pedal. The patent connects one end of the equalizer to piston of the master cylinder CBS for applying the braking force to the front wheel brake. The delay means is not in an enclosed space and the motion of actuating pin is not constrained to only axial direction.
The present invention intends to overcome limitations of prior art, provides an advancement over the prior art and discloses a solution wherein CBS means are provided to be readily adaptable for combined braking system.
It is the objective of the current invention to provide safe braking means to be used in two-wheeler.
It is another objective of the current combined braking system to provide for better braking response in two wheeler as compared to the conventional braking system.
It is yet another objective of the current invention to provide front braking means incorporating disc brake with piston caliper for facilitating separate front brake application and a separate combined brake application.
It is further objective of the current invention to provide hydraulically operated disc brake readily adaptable to be used as front wheel braking means that is adaptable with drum brake as rear braking means.
It is yet another objective of the current invention to provide floating pivot for the equalizer and different positioning of the same during rear and front braking so as to adjust itself to distribute the required force to front and rear brakes.
It is further objective of the current invention to provide bush to take the side loads from the actuating pin thereby decreasing piston wear and increasing the life of piston seals.
It is yet another objective of the current invention to provide the delay means for CBS actuation which is located such that it is enclosed within CBS master cylinder resulting in simpler delay means arrangement and.
It is yet another objective of the current invention to allow the motion of the actuating pin only in the axial direction of the CBS master piston.
BRIEF DESCRIPTION OF THE INVENTION
As illustrated in Figure No. 1, an illustrative complete view of a hydraulically operated disc brake with combined braking means is provided. The combined brake system comprises of a hydraulic disc brake (100) mounted on front wheel (40) and a mechanical drum brake (200) mounted on rear wheel (170) of a two-wheeler. Brake disc (10) is actuated by the front brake caliper (30). Master cylinder CBS (90) is mounted to the vehicle (not shown) through mounting points (92) and (94) and the actuating pin (112) motion inside the master cylinder (90) is restricted to axial direction only. The threaded holder (110) encloses the bush (115), actuating pin (112) and the delay means (116). The one end of equalizer (140) is connected to the transmission arm (130) and the other end is connected to brake rod (150), the equalizer floating pivot (109) adjusts itself to distribute force required to front and rear brakes during rear brake alone and combined braking. The pedal arm (125) and transmission arm (130) are pivoted about the point (120). When force is applied on the pedal arm (125), it gets transferred to the equalizer (140) through pivot (135). Initially equalizer (140) rotates about the floating pivot (109), and thereby the force is transferred to brake rod (150). The force thereby gets distributed to the rear wheel (170) through brake rod (150) and brake lever (155). After the rear brake (200) is actuated, the reaction from brake rod (150) results in movement of equalizer fulcrum shaft (114) in the axial direction of CBS master cylinder (90) and thereby transferring brake pressure through brake hose (85) and generating brake force in caliper (30) to stop the rotating brake disc (10).
In another embodiment as illustrated in figure no 4 is the sectional view of another embodiment of the combined brake system master cylinder in accordance with the present invention where again the combined brake system comprises of a hydraulic disc brake (100) mounted on front wheel (40) and a mechanical drum brake (200) mounted on rear wheel (170) of a two-wheeler. The motion of the actuating pin (112) is restricted to move in axial direction of the piston (118). The circlip (108) holds the bush (115), washer (107), actuating pin (112) and the delay means (116) inside CBS master cylinder (90A). Delay means (116) delays the action of actuating pin (112). The force received by the fork of the CBS master cylinder (113) gets transmitted to the piston (118) through actuating pin (112). This force gets transferred to the front brake (100), thus there is required distribution of force to both front and rear braking systems as and when required.
Although the subject matter has been described in considerable detail with reference to certain preferred embodiments thereof, other embodiments are possible. As such, the spirit and scope of the appended claims should not be limited to the description of the preferred embodiment contained therein.
BRIEF DESCRIPTION OF THE DRAWINGS
Other aspects of the invention will become apparent by consideration of the accompanying drawings and their description stated below, which are merely illustrative of a preferred embodiment of the invention and do not limit in any way the nature and scope of the invention.
Figure 1 illustrates a complete view of a combined brake system in accordance with the present invention.
Figure 2 illustrates an isometric view of combined brake system in accordance with the present invention.
Figure 3 illustrates a sectional view of combined brake system master cylinder in accordance with the present invention.
Figure 4 illustrates a sectional view of another embodiment of the combined brake system master cylinder in accordance with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The invention will now be described with reference to the accompanying drawings which do not limit the scope and ambit of the invention. The description provided is purely by way of example and illustration.
Figure 1 illustrates a complete view of combined brake system in accordance with the present invention and is generally indicated by reference numeral (1000). The combined brake system comprises of a hydraulic disc brake (100) mounted on front wheel (40) of a two-wheeler and a mechanical drum brake (200) mounted on rear wheel (170) of a two-wheeler. Brake disc (10) is actuated by the front brake caliper (30). Master cylinder CBS (90) is mounted to the vehicle (not shown) through mounting points (92) and (94). A reservoir (98) is connected to the master cylinder CBS (90) through brake hose (95) for providing hydraulic fluid. The one end of equalizer (140) is connected to the transmission arm (130) and the other end is connected to brake rod (150). The pedal arm (125) and transmission arm (130) are pivoted about the point (120). The master cylinder CBS (90) is filled with hydraulic fluid. When force is applied on the pedal arm (125), it gets transferred to the equalizer (140) through pivot (135). The force thereby gets distributed to the rear wheel (170) through brake rod (150) and brake lever (155) and also to the front wheel via CBS master cylinder (90), brake hose (85), caliper (30) and brake disc (10).
Figure 2 illustrates an isometric view of the CBS actuating system in accordance with the present invention and is generally indicated by reference numeral 1000A. The isometric view comprises of the same components as depicted in figure 1 and are herein incorporated by reference. The pedal arm (125) and transmission arm (130) rotate about a pivot (120) thereby transferring the force to equalizer (140). Initially equalizer fulcrum shaft (114) rotates about the floating pivot (109), and thereby the force is transferred to brake rod (150). After the rear brake (200) (as shown in Figure 1) is actuated, the reaction from brake rod (150) results in movement of equalizer fulcrum shaft (114) in the axial direction of CBS master cylinder (90).
Figure 3 illustrates a sectional view of combined brake system master cylinder in accordance with the present invention and is generally indicated by reference numeral 1000B. The sectional view comprises of the same components as depicted in figure 2 and are herein incorporated by reference. The motion of the actuating pin (112) is allowed to move in axial direction of the piston (118). The bush (115) minimizes the frictional movement of the actuating pin (112). The threaded holder (110) encloses the bush (115), actuating pin (112) and the delay means (116). Delay means (116) delays the action of actuating pin (112). The force received by the fork of the CBS master cylinder (113) gets transmitted to the piston (118) through actuating pin (112). This force gets transferred to the front brake (100) (as shown in Figure 1).
Figure 4 illustrates sectional view of another embodiment of the combined brake system in accordance with the present invention and is generally indicated by reference numeral 2000. The combined brake system comprises of a hydraulic disc brake (100) mounted on front wheel (40) of a two-wheeler and a mechanical drum brake (200) mounted on rear wheel (170) of a two-wheeler. The motion of the actuating pin (112) is allowed to move in axial direction of the piston (118). The bush (115) minimizes the frictional movement of the actuating pin (112). The circlip (108) holds the bush (115), washer (107) actuating pin (112) and the delay means (116). Delay means (116) delays the action of actuating pin (112). The force received by the fork of the CBS master cylinder (113) gets transmitted to the piston (118) through actuating pin (112). This force gets transferred to the front brake (100) (as shown in Figure 1).
LIST OF REFERENCE NUMERAL
10- Brake Disc
20- Front Fork
30- Caliper
40- Front Wheel
50, 60- Bleed Screw
70, 80- Banjo Bolt
75- Brake Hose from front master cylinder
85- Brake Hose from CBS master cylinder
90, 90A - CBS Master Cylinder
92, 94-Mounting of CBS master Cylinder
95-Hose from Reservoir
98-Reservoir
100-Hydraulic disc brake
107-Washer
108-Circlip for Washer
109-Floating Pivot
110-Threaded Holder
112-Actuating Pin
113-Fork of CBS Master Cylinder
114-Fulcrum of Equalizer
115-Bush
116-Delay Means
117-Circlip for Master Piston
118-CBS Master Piston
119-Oil Seal
120-Pivot for Pedal
121-Lipseal
122-Piston return Means
123-Return Means Holder
125-Pedal Arm
130-Transmission Arm of Pedal
135-Pivot between Transmission Arm and Pedal
140-Equalizer
145-Pivot between Equalizer and Brake Rod
150-Brake Rod
155-Brake Lever
160-Back Plate for Drum
170-Rear Wheel
200-Mechanical Drum Brake
1000-Combined braking system
1000A- Isometric view of the CBS actuating system
1000B-Sectional view of combined brake system master cylinder
2000-Second embodiment of the combined brake system
,CLAIMS:We claim:
1. A combined braking system (1000) for two-wheeler comprising:
• a front hydraulic disc brake (100) and a rear mechanical drum brake (200),
• a master cylinder (90) mounted to the vehicle through mounting points (92) and (94),
• an equalizer (140),
• an equalizer fulcrum shaft (114),
• a floating pivot (109),
• the one end of the equalizer (140) connected to the transmission arm (130) and the other end connected to brake rod (150),
wherein the equalizer fulcrum shaft (114) rotates about the floating pivot (109).
2. The combined braking system (1000) for two-wheeler as claimed in claim 1 wherein the master cylinder (90) comprises of a threaded holder (110) that encloses a bush (115), an actuating pin (112) and a delay means (116).
3. The combined braking system (1000) for two-wheeler as claimed in claim 1 wherein the master cylinder (90) comprises of a circlip (108) that holds a bush (115), a washer (107), an actuating pin (112) and a delay means (116).