公开(公告)号：US4942900A

公开(公告)日：1990-07-24

申请号：US412491

申请日：1989-09-26

申请人： Yusaku Nozawa ,  Kazumasa Yuasa ,  Wataru Ootu ,  Kinya Takahashi

发明人： Yusaku Nozawa ,  Kazumasa Yuasa ,  Wataru Ootu ,  Kinya Takahashi

IPC分类号： F16K17/04 ,  F15B11/00 ,  F16K17/10 ,  F16K31/363 ,  F16K31/383

CPC分类号： F16K31/3835 ,  F16K17/105 ,  F16K31/363 ,  Y10T137/7764 ,  Y10T137/7765 ,  Y10T137/7769

摘要： A pressure control valve has a main valve element of seat type slidably accommodated in a valve case for controlling communication between inlet and outlet sections of the valve case by movement of the main valve element, a control chamber defined within the valve case and between the valve case and an end face of the main valve remote from the outlet section for biasing the main valve element in a valve closing direction, and a variable restriction variable in its opening in response to the movement of the main valve element for communication between the control chamber and the inlet section of the valve case. There are provided first and second pilot lines for communication between the control chamber and the outlet section of the valve case, first and second pilot valve elements arranged respectively in the first and second pilot lines, a first valve drive unit operative in response to the pressure of the inlet section of the valve case for opening the first pilot valve element when the pressure reaches a first predetermined value, and a second valve drive unit operative in response to differential pressure between the pressure of the inlet section of the valve case and signal pressure introduced to a signal port for opening the second pilot valve element when the differential pressure reaches a second predetermined value.