Solenoid-operated pilot-actuated valve

• US 4,505,450 A
• Filed: 03/20/1981
• Issued: 03/19/1985
• Est. Priority Date: 07/13/1977
• Status: Expired due to Fees

• Current Assignee: Garden America Corporation
• Original Assignee: Richdel, Inc.
• Inventors: Saarem, Myrl J., Lovelace, Donald E.
• Primary Examiner(s): Walton, George L.
• Application Number:
  US06/245,969
• Time in Patent Office: 1,460 Days
• Field of Search: 251/30, 251/45, 251/46, 251/24, 137/484.2, 137/2, 92/103 F
• US Class Current: 251/24
• CPC Class Codes: F16K 31/402 acting on a diaphragm
• CPC Class Codes: Y10T 137/4336 Cleaning member reciprocates in passage

Abstract

A solenoid-operated pilot-actuated valve is provided of the diaphragm type which has particular utility for irrigation purposes. The valve also finds industrial utility where it is desirable to control large amounts of flow energy with a small control signal. The valve includes a diaphragm chamber into which fluid is introduced to establish a fluid pressure which normally forces the diaphragm against an annular seat in the valve to maintain the valve in a closed condition. A stationary bleed tube is provided which extends through the diaphragm into the diaphragm chamber. A solenoid plunger normally closes off the upper end of the bleed tube. However, when the solenoid is energized, the plunger is withdrawn and opens the bleed tube, the diaphragm chamber is drained sufficiently to reduce the pressure therein to a point at which the diaphragm is forced off its seat by the upstream fluid pressure, and the valve is opened. Fluid is introduced into the diaphragm chamber from the upstream fluid pressure when the valve is closed through a restricted annular passage between the bleed tube and a guide mounted on the diaphragm. Movement of the diaphragm causes the guide to move up and down with respect to the bleed tube to provide a self-cleaning action in the annular passage.

Claims

1. A solenoid-operated valve including:

a body portion defining a lower chamber with an internal seat and an inlet extending into said lower chamber, said body portion further defining an outlet;

a cap portion;

a diaphragm assembly mounted in the valve in a position to be biased against the seat and against the flow of fluids through the valve so as to control the flow of fluids through the valve from the lower chamber to the outlet, said diaphragm assembly defining a closed upper chamber in the valve with said cap portion;

said diaphragm assembly having an integral peripheral seal interposed between said cap portion and said body portion;

an open-ended nut threaded to said body portion coaxial with said cap portion to clamp said cap portion to said body portion;

a bushing-like guide member mounted in said diaphragm assembly and defining an aperture extending therethrough;

a support bracket in said lower chamber integral with said body portion;

a stationary open-ended bleed tube mounted on said support bracket and extending through the aperture in the diaphragm assembly from the lower chamber into the upper chamber, said bushing-like guide member forming an annular passage with the outer surface of said bleed tube for restricted flow of fluid from the lower chamber into the upper chamber at a rate less than the rate of flow of fluid through said bleed tube when the bleed tube is open;

a solenoid mounted on the cap portion of said valve and having a plunger positioned normally to close the upper end of the bleed tube; and

exit port means including an elongated tubular member mounted on said support bracket coaxially with said outlet and coupled to the lower end of the bleed tube through a passageway in said support bracket to provide a flow path from the upper chamber through the bleed tube and through the passageway in said bracket and through said elongated tubular member to said outlet when the plunger is retracted from the upper end of the bleed tube.

2. The solenoid-operated valve defined in claim 1, in which said diaphragm assembly has an internal metal cup-shaped reinforcing member.