| 摘要 |
A non-return valve unit comprises a body 11 having at least one inlet opening 17 and at least one outlet opening 13d for hydraulic fluid, a valve seat 14, and a closure member 20 which can move from a closure position on the seat 14 to an open position against the action of a biasing spring 22 under a pressure of liquid supplied to the inlet opening 17. Upstream of the inlet opening 17 the body 11 has an integral perforated element 18 suitable for acting as a filter for the inlet flow. |
