| 摘要 |
A PILOT VALVE (2) FOR CONTROLLING OPERATION OF A HYDRAULICALLY-ACTUATED PRESSURE REDUCING VALVE (102), THE PILOT VALVE (2) INCLUDING A HOUSING (4), AND A FIRST VALVE MEMBER MOUNTED INTHE HOUSING (4) FOR LONGITUDINAL MOVEMENT ALONG AN AXIS RELATIVE TO THE HOUSING (4) AND TO A SECOND VALVE MEMBER IN RESPONSE TO THE OUTLET PRESSURE OF THE PRESSURE REDUCING VALVE (102). THE FIRST VALVE MEMBER IS PROVIDED WITH AN APERTURE (20) AND THE SECOND VALVE MEMBER COMPRISES A CLOSURE PORTION (22) WHICH VARIES THE EFFECTIVE FLOW CROSS SECTION OF THE APERTURE (20) IN ACCORDANCE WITH RELATIVE LONGITUDINAL MOVEMENT BETWEEN THE FIRST AND SECOND VALVE MEMBERS. AN ADJUSTER (156) CONTROLS THE RELATIVE ROTATIONAL POSITION OF THE FIRST AND SECOND VALVE MEMBERS, THE CLOSURE PORTION (22) HAVING A PROFILE SUCH THAT RELATIVE ROTATION BETWEEN THE FIRST AND SECOND VALVE MEMBERS CAUSES THE CLOSURE PORTION (22) TO VARY THE EFFECTIVE FLOW CROSS SECTION OF THE APERTURE (20). |
