| 摘要 |
<p>Switching valves, e.g. for a closed-type molding apparatus for manufacturing polyurethane elastomers and the like, comprising a valve body having a plurality of openings, preferably five, serving as inlet and outlet ports, and a preferably rotatable valve sleeve which serves for switching the openings without any danger of introducing any other material into the switching valve system. Connections are made between pairs of adjacent openings, one of them being cut off from communication.</p> |
