| 摘要 |
<p>A pressure control valve wherein a pilot poppet (7) provided to control the disconnection/connection between a low-pressure relief port (12) and a back-pressure chamber (5) is constructed to perform slow and stabilized motion so as to secure a stabilized relief flow controlled by the relief flow characteristic of a relief poppet (4) provided to control the disconnection/connection between a pressure supply port (2) formed on one side of a valve body (1) and relief port (3), wherein the cross-sectional area of a piston poppet (8) slidably penetrating the relief poppet (4) and projecting into the back pressure chamber is made larger than the area of opening of the seat part (6a) of a port (6) where the pilot poppet (7) is inserted, and a constricted flow part (11) whose area of opening is gradually reduced toward the seat part is provided between the part constituting an internal circumferential surface of said port (6) extending from the seat part to the back-pressure chamber and a part of an external circumferential surface of the pilot poppet facing said part.</p> |
