| 摘要 |
<p>HYDRAULIC HANDBRAKE CONTROL SYSTEM A hydraulic handbrake control system for vehicles has a hand operable reversible fluid pump and a shuttle valve operable to circulate fluid in one direction for applying vehicle handbrakes, and in another direction for releasing vehicle handbrakes by governing flow of fluid alternately in application and release directions over application and lock release passages connected to a plurality of hydraulic handbrake cylinders. An improved lock control mechanism is associated with each of the cylinders having a check valve permitting passage of fluid from the application passage to the associated brake cylinder, but preventing release of fluid when handbrakes are applied. A lock release cylinder is associated with each handbrake cylinder and connected to the lock release passage having a lock release plunger biased to normally open the check valve that is hydraulically operable in response to pressure in the application passage to permit closure of the check valve and in response to pressure in the lock release passage to open the check valve.</p> |
