| 摘要 |
PURPOSE:To reduce the power consumption by providing first and second valves in the communication path between the delivery and suction sides of pump and a reservoir such that the first valve will open and the second valve will close under normal state while the first valve will close thereafter the second valve will open under braking and the pump will function. CONSTITUTION:Upon stepping of brake pedal 1, an input piston 2 will move to move an annular groove 24 by the distance (a) thus to close the first valve at first. Here, a switch 36 is turned on to drive a motor 19 thus to function a pump 10. While the oil in a chamber 26 between the input piston 2 and a power piston 3 is stored in an accumulator chamber 31 through a reservoir 6. Upon further movement of the input piston 2 by the distance (b), second valve will open. Consequently, the pressurized oil stored in the accumulator 37 is sucked through the pump 10 and delivered into a power chamber 5, thus to function the power piston 3. Upon returning of the pedal 1, the motor 18 will stop even if the switch 36 is turned off. While the second valve will close and the first valve will open. |
