| 摘要 |
<p>A disc brake assembly 10 in which a parking brake mechanism is housed within a piston and cylinder hydraulic actuator of the assembly, said parking brake mechanism also serving as a wear adjustment mechanism for the brake pads 12, 14 of the assembly. The parking brake mechanism comprises an actuator member 32 rotationally mounted coaxially with the piston 20 with a cylindrical portion 33 thereof extending within the piston 20, a thruster sleeve 40 slidably mounted upon said cylindrical portion 33, an adjustor sleeve 50 threadedly engaged with said thruster sleeve 40 and having a conical surface 52 thereon spring-biased into contact with a complementary coned surface 54 on the end wall 36 of the cylinder, and a retainer ring 68 within said piston 20. Compensation for wear takes place during hydraulic actuation of the brake assembly by the forward movement of the piston 20 towards a brake disc 30 causing the ring 68 to move the thruster sleeve 40 and adjustor sleeve 50 towards the disc 30. This, in turn, frees conical surface 52 from coned surface 54 and allows adjustor sleeve 50 to turn on the threaded portion 48 of thruster sleeve 40 under the bias of spring 58 to take up brake pad wear.</p> |
