| 摘要 |
PURPOSE:To prevent application of radial force onto a plunger by limiting the retracting position of plunger through a retraction limiting board secured to a power piston and advancing the plunger through energizing force of a resilient board against a power piston when returning. CONSTITUTION:A retraction limiting board 38 for limiting retraction of plunger 20 is inserted firmly into a through-hole 36 of power piston 5. Consequently, said board will never rattle even upon contact with the plunger 20 thus to prevent application of radial force onto the plunger 20. While a resilient board 39 is provided movably back and fro in a through-hole 31 of power piston 5. Upon complete returning of power piston 5, a pair of contacting sections 39b of resilient board 39 will contact against the inside face of rear housing 2 to deform the contacting section 39b forward. Said board 39 will advance through recovery force of resilient deformation untill contacting against the front wall 31a of communication path 31 to advance the plunger 20 slightly thus to reduce the gap of valve 18 from C1 to C3. |
