| 摘要 |
A fluid-flow control valve in which flow between inlet and outlet pipe connections 2, 3 passes through the bore of a helical compression spring 5 and between the convolutions thereof when the spring is at least partly relaxed. The spring 5 can be compressed by turning a handle 12 to turn a cam 9 to open and close the convolutions of the spring 5. When the spring 5 is fully compressed, the convolutions are closed fully together thereby shutting the valve and interrupting flow therethrough. The spring 5 may be made of or be coated with an elastomeric material which will be compressed to provide a seal when the convolutions are fully closed together. <IMAGE> |
