Dual circuit brake booster - has yoke spring coupled to one parallel booster piston to decouple on booster failure

摘要

The booster pistons (5,6) are in parallel bores and linked by a yoke (14). The yoke is rigidly secured to the end of one piston (5) and has a sliding fit (17) on the other piston, limited by a stop (16). A spring (18) provides the coupling force, which is overcome to decouple the pistons on the booster failure.S The yoke coupling has a minimum of components and requires only simple tolerances. There is no danger of a twisted yoke jamming the booster action. The two pistons are of unequal size and the spring has a low return force.