| 摘要 |
PROBLEM TO BE SOLVED: To adjust an input side stroke so as to become the same as a stroke at ordinary brake operation time even if wheel cylinder(WCY) pressure changes. SOLUTION: When a master cylinder(MCY) 1 generates MCY pressure by an advance of a primary inner piston 9, a pump of a brake force control device arranged between the MCY 1 and the WCY sucks in a brake fluid from the MCY 1, delivers the brake fluid to the WCY, and generates WCY pressure controlled according to various brake operations. This WCY pressure is supplied to a brake force control pressure chamber 40, and acts on a step part 8e of a primary outer piston 8. The outer piston 8 relatively moves to the primary inner piston 9 so that force by the MCY pressure, force by the WCY pressure, force by spring force of a control spring 13, and sliding resistance force of a part for liquidtightly sliding the primary outer piston 8 balance with each other, and a pedal stroke is adjusted in the same as the ordinary brake operation time. |
