| 摘要 |
A vacuum-operated brake power booster, including a control valve comprising a control valve piston with valve seat actuated by the piston rod, a poppet valve with two valve seat faces and a valve seat at the longitudinally slidable control valve body. The movements of the poppet valve relative to the two valve seats are controlled by a transverse member embracing the neck of the poppet valve. The radially external end of the transverse member touches the stationary sealing ring in the release position of the brake. For the purpose of interaction of the poppet valve with the transverse member, the neck of the poppet valve is furnished with an annular groove at its radially external peripheral surface, the width of the annular groove being sized larger than the thickness of the transverse member which engages in that groove. With the transverse member touching against the stationary sealing ring on the one hand and with the exactly sized axial play between the transverse member and the poppet valve on the other hand, the lost motion of the valve is reducible to zero. |
