Bosch Braking Systems Co. Ltd.

Yoshiyuki Hiratsuka

Hidefumi Inoue

Yasushi Mori

Takasaki Yoshiyasu

A first vacuum valve seat is formed on a valve body , and a second vacuum valve seat is formed on a tubular member which is slidably mounted on the valve body . A lever member is provided between the tubular member and a valve plunger , and when the valve plunger strokes through a given stroke or more relative to the valve body , the lever member moves angularly to retract the tubular member rearward relative to the valve body . When a brake pedal is quickly depressed, the lever member moves angularly to cause an engaging tab to engage an engaging recess formed in the valve body , thus retaining the tubular member at a position which is reached as it is retracted rearward relative to the valve body . This allows an atmosphere valve to be opened to a greater opening than during a usual operation, allowing an increased output to be obtained rapidly. The present invention allows an output from a brake booster to be increased rapidly as an immediate response to a quick depression of the brake pedal.

Growing community of inventors

Saitama-ken, Japan

Yoshiyuki Hiratsuka