Disc for a Disc Brake System

Field of the invention

The present invention relates to mechanisms for sensing the speed of a wheel of a two-wheeler which has an anti lock brake system or ABS.

Background of the invention

Generally, a signal generating mechanism and a signal-receiving device are required to be mounted in the vicinity of wheel of a two-wheeler to generate signal for activating speed sensing mechanism. Wheel speed sensing is one of the input for the electronic control unit (ECU) of a ABS vehicle apart from other inputs. The speed sensed by the ECU is used for charging response of other elements of ABS. The wheel speed can be sensed many ways by mounting a sensor 302 and a sensor wheel 303, where former 302 is stationary and latter 303 is rotating. The sensor unit 302 is a electronic unit with hall effect or other similar arrangement. The signal generator for the sensor to sense is mounted on the rear and front hub of the wheel to close proximity of sensor unit 302. The sensor works on the principle of change in distance between sensor face and sensor wheel.

In an known conventional technique disclosed in Japanese laid open No- H8 133154 the toner ring 303 is generally provided with teeth since the teeth are relatively long and slender, the toner ring teeth will be subjected to warpage and hence would lead to more machine and labor cost for repairing warpage. In order to address the above said disadvantage as disclosed in 848/MUM/2000, a separate disc mounted along the disc brake disc with rectangular holes on a circular pitch manufactured by a known method of punching and pressing is provided. However this technique demands additional sensor cable routing to align the sensor face with the slot edges, thus leading to increased cost. Further the above said arrangement involves more numbers of parts, for which mounting requires additional bolts. In order to overcome above disadvantages a new way of signal generation and receiving method is disclosed.

Brief description of the present invention:

The present invention has been devised in view of the above difficulties and it is therefore an object of the present invention is to provide flexibility in mounting orientation of the speed sensing element or sensor such that the sensor's sensing face or edge is parallel to the edge of the slot formed on the toner assembly. Accordingly, the brake disc used in disc brake arrangement is provided with equally spaced uniform slots provided on a pitch circle drawn with respect to the centre of the brake disc. The sensor detects the slots on the disc brake for determining the wheel speed.

Brief description of the drawings

Figure 1 illustrates side view of a motorcycle.

Figure 2 illustrates the pulsar ring arrangement according to the prior art. Figure 3 illustrates the disc brake according to the present invention used for sensing the speed of wheel with a sensor.

Detailed description of the present invention

A selected illustrative embodiment of the present invention will be now described with respect to the accompanying figures 1,2 and 3.

A motorcycle comprises of a frame 101, front fork 102 attached to a pivot tube 103 of the vehicle frame 101, a front wheel 104 attached to these front forks 102, a handle bar 105 connected to the front forks 102, a fuel tank (not shown in the figure) attached so as to straddle an upper part of the vehicle frame 101, a seat 107 attached to the upper rear portion of the vehicle frame 101, an engine unit 108 attached to the lower front section of the vehicle frame 101, a swing arm 109 attached to a lower rear section of the vehicle frame 101, suspended by a rear shock absorber 110 from the vehicle frame 101 and a rear wheel 111 attached to a rear end of swing arm 109. The intake system of the engine (not shown in the figure) comprises of a carburettor, intake duct and an air cleaner. The exhaust system of the engine 108 comprises of exhaust pipe 202 and a muffler 205.

The motorcycle is also provided with a side cover for covering a side section of the vehicle frame 101, a front fender 113 for covering an upper part of the front wheel 104, and a rear fender 114 for covering an upper part of the rear wheel 111. A disc brake 301 is also provided in the front wheel 104 for braking purposes. To measure the wheel speed, a sensing element is attached to the disc brake mounting structure as a stationary element. According to one of embodiments of the present invention, the brake disc 301 used in disc brake arrangement is provided with equally spaced uniform slots 305 provided on a pitch circle 306 drawn with respect to the centre 307 of the brake disc 301. The sensor 302 detects the slots 305 on the disc brake 301 for determining the wheel speed. The present arrangement eliminates the use of a separate pulsar ring and thus reduces the cost as well as the part count. Moreover, the slots 305 provided on the disc brake 301 are also used for cooling purpose of the disc brake 301. Hence it provides an effective design that is not only cost effective but has low maintenance and high durability.

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.

Claim

We claim:

1. A wheel speed-detecting device for a motorcycle comprising a brake disc 301 used in disc brake arrangement wherein the said brake disc 301 is provided with equally spaced uniform slots 305 provided on a pitch circle 306 drawn with respect to the centre 307 of the brake disc 301 for sensing the wheel speed.

2. A motorcycle comprising a brake disc 301 as claimed in claim 1.