| 摘要 |
<p>A valve particularly for anaesthesia and patient ventilation comprises a valve member (14) which is urged by a spring (13) to close a valve seat (24), thereby controlling flow of gases between inlet (11) and outlet (12) ports of the valve housing. An annular control member (17) within the valve housing can be rotated by a cap (20) so as to displace member (17) axially, thereby positively lifting the valve member (14) off the valve seat (24) when it is desired to open the valve. Formations (16 and 28) on the valve seat (24) and on the control element (17), respectively, define an annular gap for the passage of gases through the opened valve which progressively increases as the control element moves in the valve-opening direciton.</p> |
