| 摘要 |
A twin cylinder pump for viscous materials such as concrete, having a guide for a cutting ring producing a sealing effect on the cylinder and a seat for supporting a loaded spring ring of elastic material of rubber or the like, is so designed that the ring is acted upon by the pressure of the feed taking effect in the ring-like gap, open as far as supporting face or seat of the spring, between the cutting ring and the valve member. Furthermore there is a guiding and constraining means for the ring taking effect thereon between the radial faces against which it is rested. |
