| 摘要 |
1284207 Warning devices; spot-type disc brake ALFRED TEVES GmbH 19 April 1971 [26 March 1970] 24510/71 Heading F2E A brake, especially a spot-type disc brake, incorporates apparatus for indicating the limit of permissible wear of brake friction linings 9, 13 and 10, 14 and comprising an insulated electrical conductor 21 through which an electric current is passed arranged at a non-displaceable part of the brake so that when the friction linings are worn the insulation of the conductor 21 is partially destroyed and a short-circuit is created to cause actuation of an alarm device such as a lamp. As shown in Fig. 1 the conductor 21 is coiled round an arm 20 of a cross-spring 16 which spring 16 acts as a retaining spring whose U-shaped arms 17, 18 rest against back plates 9, 10 respectively of the linings while the other two arms 19, 20 of the spring 16 embrace guide pins 11, 12 from below and are supported by them. The back plates 9, 10 of the friction linings are movable on the pins 11, 12 when pistons 5, 6 in wheel cylinders 3, 4 are actuated to operate the brake and as the back plates 9, 10 get closer to one another they will eventually touch the conductor 21, force the insulation off and create a short circuit to energize the alarm device. As shown in Fig. 3 the conductor is coiled as at 24 and 25 around the pin 11 and as the bearing supports 22, 23 of the back plates 9, 10 move towards each other they will destroy the the insulation of the wire coil 24, 25. The alarm device has an electrical power source with one pole connected to the spring 16 and thence to the alarm device: electrical connectors are provided at the brake caliper halves 1, 2. In the embodiment of Fig. 4 the disc brake does not incorporate a spring and the insulated wire 33 is led through two transverse bores 31, 32 in a pin 30. In the embodiment of Fig. 5 (not shown) the pin (37) is provided with a spacer sleeve (38) the length of which corresponds approximately to the width of the brake disc and the wire (37) has at least one coil resting between an end face (40) of the spacer sleeve (38) and the back plate moved on the pin (37). The invention is said to be applicable also to drum brakes, wedge brakes or handbrakes. |
