Combined Braking System

Field of the Invention

The present invention relates to "Combined Braking System". In particular this invention relates to front and rear combined brake system for two-wheeled vehicle.

Background of the invention

In most of the present two wheeler braking systems, both front and rear brakes are independently operated i.e. application of front brake force will activate only front wheel brake and rear brake force will activate only rear wheel brake. Rear brake force application is limited, because of dynamics of vehicle during braking. Due to load transfer to front wheel during braking, further increase in rear brake force will result in skidding rather than stopping the vehicle. Vehicle controlling becomes difficult and stopping distance will be more, thereby resulting in poor braking performance due to wheel skidding. So typically in a combined brake system the available braking force is completely utilised by distributing it to front and rear brake, thereby the stopping distance is minimized in two wheelers. As disclosed in JP2004352181 the interlocking brake device ( or combined braking system), has an interlocking brake manipulating cable which is connected to an intermediate portion of an equalizer lever, which forms a front wheel brake manipulating end portion at one end portion thereof and a rear wheel brake manipulating end portion at another end portion thereof, either one of the front brake cable and the rear brake cable is formed as one independent brake manipulating cable which is connected to an independent brake manipulating member, an engaging member which is capable of being engaged with and being disengaged from the equalizer lever is mounted on the independent brake manipulating cable. In this brake system arrangement, the equalizer lever can tilt towards the wall and hit the spring placed around it. This tilting can lead to mechanism lockage. And during this lockage the front brake application is not possible. Since one spring is used to retain the equalizer in its original position, much brake force is wasted to move the equalizer against the spring. The provision of engaging member resting on equalizer lever slot which is an integral part of the brake cable for sliding and relative rotation is subject to wear and tear for continuous rubbing and sliding inside the slot. To replace the said engaging member the entire cable has to be changed.

In another patent JP9058434 which discloses a longitudinal interlocking brake (or combined brake) practicable through a structure by applying a mechanism, which generates only rear wheel brake force in an early time of brake operating input, but as the brake operating input exceeds a prescribed value, it can generate braking force even at the front wheel. In the above said mechanism there is one input and two output for which the independent lever mechanism is placed longitudinally opposite to the combined lever mechanism, thereby during rear brake application, front brake activation line length is more. The problem associated with this is that it is incapable of providing good brake feel. Since there is only one input, the equalizer lever is not supported and guided during brake operation. At the end of rear brake application, application of the front brake will result in tilting of equalizer lever thereby hitting the wall.

In another patent JP2000309294 which discloses a interlocking brake system (or combined brake system) having an equalizer lever accommodated inside an equalizer case disposed near a head pipe, where a first input cable is connected to an interlocking brake lever which is axially supported at one end of a steering handle and is connected to a mid portion of the equalizer lever. Further a first output cable and a second output cable connected to a rear wheel brake and a front wheel brake are connected 1o a first end and a second end of the equalizer lever. In this kind of arrangement there is no support /guiding system for front brake circuit (i.e. is not guided). During rear brake operation, the resultant thrust coming on pin joint of intermediate arm can make front brake circuit to deflect in lateral direction of the cable. This results in mechanism lockage and rubbing of front brake wire with casing walls. The other disadvantage is front brake input cable end is free to slide in the slot due to improper guiding of the joint member the front brake input cable end may bend. For which more rear brake activation force is required during interlocking braking. Even the brake cable wire endpin rotation is not allowed inside that slot. Unnecessary work is also done against the spring which is used in the front brake circuit for initiation for interlocking brake.

In fact in all the known combined brake system arrangement principally the front and rear output are in the same direction or same side thereby rendering restrictions and problems for cable routing

Hence the objective of the present invention is to overcome the above problems associated with the prior arts.

Summary of the Invention

An object of the present invention is to provide a combined braking system for two wheeled vehicle which provides better dynamics and safety.

Another object of the present invention is to provide a combined braking system for two wheeled vehicle where the brake circuits are guided properly thereby improving the braking feel.

Another object of the present invention is to provide a combined braking system for two wheeled vehicle where the front brake cable wire bending is avoided.

Another object of the present invention is to provide a combined braking system for two wheeled vehicle which will minimize the length of cable routing.

Yet another object of the present invention is to provide a cost effective arrangement for combined brake system.

Further object of the present invention is to provide a combined brake system with reduced part counts.

Further object of the present invention is to provide a combined brake system which renders easy packaging in the two wheeled vehicle.

Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.

Brief Description of the Drawings:

The present invention will become more fully understood from the detailed description given herein below and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein

FIG. 1 is a left side view of a two wheeled scooter type vehicle.

FIG. 2 is one embodiment according to the present invention.

FIG. 3 shows the positions of the levers when the input cable is first pulled according to the present invention.

FIG. 4 shows the positions of the levers when the input cable is further pulled according to the present invention.

FIG. 5 is second embodiment according to the present invention.

FIG. 6 shows third embodiment according to the present invention.

FIG. 7 shows fourth embodiment according to the present invention.

FIG. 8 shows fifth embodiment according to the present invention.

Detail Description of the Drawings:

The present invention relates to combined braking system for a two wheeled vehicle. For the purpose of illustration a scooter of the general type is illustrated for the application. A reference number 1 in Fig.1 denotes a front wheel, 2 denotes a front fork, 3 denotes a front fender, 4 denotes a front cover, 5 denotes a leg shield made of resin or metal, 6 denotes a handle bar cover, 7 denotes a headlight, 8 denotes a handle bar ,17 denotes a rear fender and 18 denotes tail lamp. The center of the body forms a low floor board 9 for functioning as a part for putting feet and a under cowl 10 which is located below the rider's seat and covers at least a part of the engine, The under cowl is made up of metal or resin. The under cowl is hinged to the seat 11. A utility box 12 opens from the rear end to hinged portion. The utility box 12 is provided under the seat extending longitudinally of a vehicle body and the inside of the utility box has a large capacity so that a large article can be housed. A main frame 14 extended along the center of the body before and behind and made of a metallic pipe and is provided under the floor board 9. A swing type power unit 13 is coupled to the rear end of the main frame 14.

A rear wheel 15 is supported on one side of the rear end of the swing type power unit 13. The swing type power unit 13 is suspended in the rear of a body frame.

The side covers 16 both on left and right sides, covers the utility box 12 and other parts of the vehicle, thereby providing a good appearance to the vehicle.

The combined brake system according to one of the embodiment of the present invention is preferably located in the floor board of the scooter type two wheeler vehicle.

According to one embodiment of the present invention and referring to figure 2, the said combined brake system is provided with two levers one primary or main lever (201) and one secondary lever (202). The said primary lever (201) sits over the secondary lever (202). The said secondary lever (202) is preferably half the length of the primary lever (201). The said secondary lever (202) one end (203) is attached to the bottom surface (204) of the casing of the combined brake system through a hinge joint (209). The other end of the secondary lever (205) is provided with a pin joint (206) which slides in a slot (207) provided in the said primary lever (201). A spring (208) is connected between the secondary lever (202) and the bottom surface of the casing (204). The said spring (208) is placed between the said hinge joint (209) and the said pin joint (206).

An input cable (210) from one of the brake control lever is connected to the primary lever (201). And a first output cable (212) and second output cable (211) from the primary lever (201) is connected to rear brake and front brake respectively. The said first and second output cables are in mutually opposite direction. The second output cable (211) from the primary lever is attached to that end of the primary lever which is opposite to the slot end of the said primary lever through any of the means known in the art. The said input cable (210) is connected to the primary lever (201) on the other end towards the vicinity of the slot (207). The first output cable (212) which goes to rear brake is connected to the primary lever (201) at a location which is in between the second output cable t211) and the input cable (210). The first and second output cable are connected in mutually opposite direction to each other, they are on different sides of the primary lever. The input cable (210) and the second output cable (211) are preferably on the same side of the primary lever (20,1) and the first output cable (212) is on the other side of the primary lever. At least one independent brake control lever is independently operated to apply the front brake. The other combined brake lever is operated to pull one of the said one input cable (210) which thereby activates the further working of combined brake system.

Referring to figure 3, once the said input cable (210) is pulled, the primary lever (201) pivots about the pin joint (206) at the end of the secondary lever (202). The said primary lever rotates in the direction of the pull (shown as arrow A), thereby pulls the first output cable (212), which activates the rear brake. On further pulling of the input cable (210), the primary lever (201) starts rotating about the first output cable (212) connection point, which is in opposite direction to the previous mentioned direction. Primary lever slot end (205) moves in the direction of the input cable (210), thereby pulling the second output cable (211). The pulling action of second output cable (211) actuates or activates the front brake, (shown in figure 4) To accommodate this movement of the primary lever (201) wherein second output cable (211) is pulled, the said primary lever allows sliding of the pin (206) provided in the secondary lever to slide in the slot (207) provided in the primary lever. The said slot pin arrangement helps to vary the spring force and simultaneously a less resistive force is developed which further helps in reducing the application force at the brake input lever.

According to other aspect of the first embodiment of the present invention, the secondary lever (202) sits over the primary lever (201). The said secondary lever
(202) is preferably half the length of the primary lever (201). The said secondary lever (202) one end is attached to the upper surface of the casing of the combined brake system through a hinge joint. ,

And the rest arrangement and working of the combined brake system remains the same as mentioned above in the first embodiment.

According to the second embodiment of the present invention and referring to figure 5, the primary lever (601) and the secondary lever (602) are connected by pin joint (603) and no slot is provided on the said primary lever. A spring (604) is attached between the said secondary lever (602) and the bottom casing surface (605) by hinge joint (606). One input cable (607) and two output cables (608,609) are connected to the said primary lever (601), wherein the two output cables (608, 609) are in mutually opposite direction. Among the two said output cables the one output which activates the rear brake is located in between the input cable and the other output cable which activates the front brake. The input cable and the output cable which activates the front brake are in the same direction.

According to the third embodiment of the present invention and referring to figure 6 a single lever (701) is provided, wherein at one extreme end, a spring (702) is provided.

The said spring (702) is attached between the said lever (701) and the bottom casing surface (703) by any methods known in the prior arts. One input cable (704) and two output cables (705, 706) are connected to the said lever (701), wherein the two output cables are in mutually opposite direction. Among the two said output cables the one output which activates the rear brake is located in between the input cable and the other output cable which activates the front brake. The input cable and the output cable which activates the front brake are in the same direction. According to the other aspect of the third embodiment of the present invention one input cable (704) and two output cables (705, 706) are connected to a single lever (701). The said two output cables are in mutually opposite direction to each other. Among the two said output cables the one output which activates the rear brake is located in between the input cable and the other output cable which activates the front brake. The input cable and the output cable which activates the front brake are in the same direction.

According to the fourth embodiment of the present invention and referring to figure 7 the said combined brake system (801) is located in the floor board (802) of scooter type two wheeler.

According to the fifth embodiment of the present invention and referring to figure 8, the combined brake system described above is implemented in the motorcycle having front and rear drum brakes and is preferably located in at least one of the down tubes of the motorcycle. The said one down tube extends obliquely from secondary portion of the head tube towards back.

It is further to be noted that the present invention is not limited to the described embodiment and many other changes and modifications may be made without departing from the scope of the appended claims.

We Claim:

1. A combined brake system for two wheeler comprises:

at least one primary lever;

at least one secondary lever;

at least one spring;

at least one input cable; and

at least twp output cables;

wherein the said output cables are in mutually opposite direction to each other;

wherein the said output cable which actuates the rear brake is placed in between the said input cable and the said output cable which actuates the front brake; and

wherein the said one input cable and one output cable which actuates the front brake is in same direction.

2. The combined brake system as claimed in claim 1, wherein the said lever is connected to the secondary lever.

3. The combined brake system as claimed in claim 1, wherein the said primary lever is connected to the secondary lever through pin joint.

4. The combined brake system as claimed in claim 1, wherein the said primary lever sits over the secondary lever.

5. The combined brake system as claimed in claim 1 and claim 4, wherein the said spring is connected between the secondary lever and the bottom surface of the casing.

6. The combined brake system as claimed in claim 1, wherein the said secondary lever sits over the primary lever.

7. The combined brake system as claimed in claim 1 and claim 6, wherein the said spring is connected between the secondary lever and the top surface of the casing.

8. The combined brake system as claimed in claim 1, wherein the said spring is connected to the secondary lever.

9. The combined brake system as claimed in claim 1, wherein the said primary lever is provided with a slot at one end.

10. The combined brake system as claimed in claim 1 and claim 7, wherein the said secondary lever one end is provided with a pin which slides in the slot provided in the primary lever.

11 .A combined brake system for two wheeler comprises:

at least one lever;

at least one spring;

at least one input cable; and

at least two output cables;

wherein the said output cables are in mutually opposite direction to each other;
wherein the said output cable which actuates the rear brake is placed in between the said input cable and the said output cable which actuates the front brake; and

wherein the said one input cable and one output cable which actuates the front brake is in same direction.

12. The combined brake system as claimed in claim 11, wherein the said spring is connected to the lever at its one end.

13. A combined brake system for two wheeler comprises:

at least one lever;

at least one input cable; and

at least two output cables;

wherein the said output cables are in mutually opposite direction to each other;

wherein the said output cable which actuates the rear brake is placed in between the said input cable and the said output cable which actuates the front brake; and

wherein the said one input cable and one output cable which actuates the front brake is in same direction.

14. The combined brake system as claimed in claim 1, claim 11 and claim 13, is preferably disposed in at least one down tube of the motorcycle.

15. The combined brake system as claimed in claim 1, claim 11 and claim 13, is preferably disposed in the floor board of scooter type two wheeler.

16. A combined brake system for motorcycle characterized in that at least one lever is housed within a case disposed in at least one down tube;

at least one input cable connected to the said lever; and

at least two output cables connected to the said lever in mutually opposite direction.

17. A combined brake system for scooter type two wheeler characterized in that

at least one lever is housed within a case disposed in the floor board;

at least one input cable connected to the said lever; and

at least two output cables connected to the said lever in mutually opposite direction.