| 摘要 |
A disc brake includes a positioning device (40) which is pressure responsive to control the amount of retraction for a piston (22) within the disc brake. The positioning device includes a plug (44) movably and sealingly carried within the piston (22) and a pair of legs (48, 50).The plug (44) cooperates with the pair of legs (48, 50) to move the latter to a position in spaced relation to a caliper housing (12) when the pressure level within a pressure chamber (28) is above a predetermined value. A spring (52) cooperates with the plug (44) and the pair of legs (48, 50) to engage the latter with the caliper housing (12) when the fluid pressure within the pressure chamber (28) is below the predetermined value. |
