| 摘要 |
<p>PURPOSE:To reduce the pedal depressing force following loss stroke by relieving the set pressure at a supply chamber with the opening of a valve by a primary piston close to the completion of the loss stroke in a master cylinder used for hydraulic brake device or the like. CONSTITUTION:When the action of a brake presses a primary piston 3, a seal 9 seals a pressure chamber 16 passing a port 34. At the same time, as the capacity of a supply chamber 10 decreases, liquid in the chamber 10 is sent to the pressure chamber 16 passing between a path 6, the seal 9 and a small hole 1b and then, sent to the brake system with a liquid in the chamber 16. When the pressure in the chamber 10 becomes high, a valve 30 opens to relieve the pressure to a reservoir 2 whereby the pressure in the chamber 10 is retained at a set level. When the liquid is sent to start the braking action in the brake system, the valve 30 opens by the action of the shoulder part 3f of the piston 3 to release the set pressure in the chamber 10 to the atmospheric pressure thereby reducing the depressing force in the subsequent pedal stroking.</p> |
