Autoclosing flow-control valve
First Claim
1. An autoclosing flow-control valve assembly comprising:
- a housing forming an inlet chamber normally filled with a fluid under pressure, an outlet chamber, and a main valve seat between the chambers;
a piston defining in the housing a control chamber;
a valve element carried on the piston and engageable with the seat, the piston and valve element being displaceable in the housing between a closed position with the element engaging the seat and blocking flow between the chambers and an open position with the element clear of the seat and permitting flow from the inlet chamber to the outlet chamber;
a piston spring braced between the piston and the housing and urging the piston and element backward into the closed position, the control chamber being of substantially smaller volume in the closed position than in the open position, the piston being formed with a small bleed passage extending between the control chamber and the outlet chamber;
means including a control passage extending between the inlet chamber and the control chamber and a pilot valve in the control passage for, in an open position of the pilot valve, pressurizing the control chamber and pushing the piston and element into the open position and, in a closed position of the pilot valve, for blocking flow through the control passage;
an actuating member axially movable on the housing and actuatable to open the pilot valve;
an actuating spring braced between the member and the housing and urging the member out of contact with the pilot valve;
a bypass passage extending between the control chamber and the outlet chamber and of substantially greater flow cross section than the bleed passage; and
a bypass valve in the bypass passage normally blocking flow therethrough and openable by actuation of the actuating member to permit flow through the bypass passage, whereby when the actuating member is actuated with the control chamber full the control chamber can be quickly drained and the valve element and piston moved by the spring into the closed position.
2 Assignments
0 Petitions
Accused Products
Abstract
An autoclosing flow-control valve assembly has a housing forming an inlet chamber normally filled with a fluid under pressure, an outlet chamber, and a main valve seat between the chambers. A piston defining in the housing a control chamber carries a valve element sealingly engageable with the seat. A piston spring braced between the piston and the housing urges the piston and element into the closed position. The piston is formed with a small bleed passage extending between the control chamber and the outlet chamber. A control passage extending between the inlet chamber and the control chamber has a pilot valve that when open pressurizes the control chamber and pushes the piston and element into the open position and when closed blocks flow through the control passage. An actuating member is actuatable to open the pilot valve and an actuating spring braced between the member and the housing urges the member out of contact with the pilot valve. A bypass passage extending between the control chamber and the outlet chamber is of substantially greater flow cross section than the bleed passage. A bypass valve in the bypass passage normally blocks flow therethrough and is opened by actuation of the actuating member to permit flow through the bypass passage so that when the actuating member is actuated with the control chamber full the control chamber can be quickly drained and the valve element and piston moved by the spring into the closed position.
35 Citations
13 Claims
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1. An autoclosing flow-control valve assembly comprising:
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a housing forming an inlet chamber normally filled with a fluid under pressure, an outlet chamber, and a main valve seat between the chambers; a piston defining in the housing a control chamber; a valve element carried on the piston and engageable with the seat, the piston and valve element being displaceable in the housing between a closed position with the element engaging the seat and blocking flow between the chambers and an open position with the element clear of the seat and permitting flow from the inlet chamber to the outlet chamber; a piston spring braced between the piston and the housing and urging the piston and element backward into the closed position, the control chamber being of substantially smaller volume in the closed position than in the open position, the piston being formed with a small bleed passage extending between the control chamber and the outlet chamber; means including a control passage extending between the inlet chamber and the control chamber and a pilot valve in the control passage for, in an open position of the pilot valve, pressurizing the control chamber and pushing the piston and element into the open position and, in a closed position of the pilot valve, for blocking flow through the control passage; an actuating member axially movable on the housing and actuatable to open the pilot valve; an actuating spring braced between the member and the housing and urging the member out of contact with the pilot valve; a bypass passage extending between the control chamber and the outlet chamber and of substantially greater flow cross section than the bleed passage; and a bypass valve in the bypass passage normally blocking flow therethrough and openable by actuation of the actuating member to permit flow through the bypass passage, whereby when the actuating member is actuated with the control chamber full the control chamber can be quickly drained and the valve element and piston moved by the spring into the closed position. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13)
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Specification