| 摘要 |
PROBLEM TO BE SOLVED: To prevent a push rod and pedals in a crew compartment from returning to a driver side with the low cost without changing a structure of a car body and the like in a case where the external force acts on a hydraulic generator from the front of the car body by forming a recessed groove on an inner part of an engagement hole of a rear cylinder of a master piston. SOLUTION: A hydraulic generator 6 is projected on an engine room 1 side of a dash panel 3, and a valve housing 4b of a booster 4, a push rod 7 and an operation pedal 8 are arranged in a crew compartment 2. An engagement hole 50b is formed on a rear cylinder 50a of a master piston 50 inserted into a cylinder hole 5d of a hydraulic master cylinder 5. A shaft of small diameter 19b of an output rod 19 is inserted into the engagement hole 50b. A spiral recessed groove 50e is engraved on the engagement hole 50b over approximately 2/3 depth from a rear end surface 50d. The rear cylinder 50a is broken at a fragile part of the recessed groove 50e when the master piston 50 is inclined from a central shaft CL with the master cylinder 5 by the excess external force from the front of the car body. |
