| 摘要 |
<p>A simple, reliable pressure control valve (21) for a medical device having a hydraulic system comprises an outer jacket (30) having an inlet (31) and an outlet (32) positioned between the inlet (31) and outlet (32) is a valve housing (33). A poppet (34) with an upwardly extending stem (35) is movably mounted in the housing (33). The poppet (34) has an annular seal (36) mounted on the poppet (34) circumferentially about the stem (35), and is supported by a calibrated spring (37) urging the poppet (34) towards the open top of the housing (33) so that the sealing edge (38) of the seal (36) is in sealing contact with the underside of a flange (39) which partially closes the top of the housing (33). The stem (35) extends above the top of said housing (33) so that manual pressure can be exerted upon the stem (35) to open the valve (21) or the valve can be opened by a hydraulic pressure which exerts sufficient force upon the top of the poppet (34) to overcome the force of the spring (37).</p> |
