| 摘要 |
<p>A drum brake hydraulic wheel cylinder assembly comprises a pair of piston assemblies and an abutment member. The piston assemblies are of the kind comprising an adjustable variable length tappet assembly having interengaged screw-threaded components. To enable thrust to be transmitted from one adjacent brake shoe to the other, i.e. for parking purposes, the abutment member is slidable in the cylinder bore against a spring centering device.</p> |
