Fluid control valve with soft startup

• US 5,699,829 A
• Filed: 05/14/1996
• Issued: 12/23/1997
• Est. Priority Date: 05/14/1996
• Status: Expired due to Term

• Current Assignee: ROSS Operating Valve Company
• Original Assignee: ROSS Operating Valve Company
• Inventors: Bareno, Hendrik Pieter, Weiler, Charles A. Jr.
• Primary Examiner(s): Michalsky, Gerald A.
• Application Number:
  US08/645,679
• Time in Patent Office: 588 Days
• Field of Search: 91/31, 91/29, 137/383, 137/596, 137/625.68
• US Class Current: 137/383
• CPC Class Codes: F16K 31/48 actuated by mechanical timing-device, e.g. with dash-pot self-closing valves F16K21/16
• CPC Class Codes: Y10T 137/7069 With lock or seal
• CPC Class Codes: Y10T 137/86702 With internal flow passage
• CPC Class Codes: Y10T 137/87169 Supply and exhaust

Abstract

A fluid control valve includes an adjustable soft start capability. The fluid control valve isolates an input port and connects an outlet port to an exhaust port when the fluid control valve is in its closed position. A system is provided for locking the fluid control valve in the closed position. When the fluid control valve is moved to an open position, the exhaust port is isolated and full communication between the input port and the outlet port is delayed by a piston which continues to block fluid flow between the input port and the outlet port. An adjustable by-pass passage bleeds pressurized fluid from the input port around the piston to the outlet port until a specified pressure is built up at the outlet port. When the pressure at the outlet port reaches the specified pressure, the piston is moved from a position which blocks the flow from the input port to the outlet port to a position which allows full communication between the input port and the outlet port.

Claims

1. A fluid control valve comprising:

a valve housing defining an inlet port, an outlet port and an exhaust port;

a valve spool assembly movable with respect to said valve housing between an open condition and a closed condition, said inlet port being in communication with said outlet port when said valve spool assembly is in said open position, said outlet port being in communication with said exhaust port when said valve spool assembly is in said closed position; and

means associated with said valve spool assembly for delaying full communication between said inlet port and said outlet port when said valve spool assembly is moved from said closed position to said open position, said delaying means comprising;

a piston slidably disposed upon said valve spool assembly, said piston blocking said full communication between said inlet port and said outlet port when said valve spool assembly is initially moved from said closed position to said open position; and

a by-pass passage disposed between said inlet port and said outlet port, said by-pass passage being opened when said valve spool assembly is initially moved from said closed to said open position, said by-pass passage allowing fluid to flow from said inlet port to said outlet port at a specified rate, said piston being moved to allow said full communication between said inlet port and said outlet port when fluid pressure at said outlet port reaches a specified value.

2. The fluid control valve according to claim 1 wherein, said specified rate is adjustable.

3. The fluid control valve according to claim 1 further comprising retaining means for releasably securing said valve spool assembly in said open or said closed condition.

4. The fluid control valve according to claim 1 further comprising means for locking said valve spool in said closed position.

5. A fluid control valve comprising:

a valve housing defining an inlet port, and outlet port and an exhaust port;

a valve spool assembly movable with respect to said valve housing between an open condition and a closed condition;

a first passage extending between said outlet port and said exhaust port;

a second passage extending between said input port and said outlet port

a third passage extending between said input port and said outlet port; and

a piston slidably disposed upon said valve spool assembly, said piston closing said second passage and opening said third passage when said valve spool assembly is moved from said closed position to said open position, said piston opening said second passage a specified period of time after said valve spool assembly is moved to said open position.

6. The fluid control valve according to claim 5 wherein, said specified period of time is controlled by an orifice disposed within said third passage.

7. The fluid control valve according to claim 6 wherein, said orifice is adjustable.

8. The fluid control valve according to claim 5 wherein, said specified period of time is adjustable.

9. The fluid control valve according to claim 5 further comprising means for locking said valve spool in said closed position.

10. A fluid control valve comprising:

a valve housing defining an inlet port, an outlet port and an exhaust port;

a first passage extending through said housing connecting said outlet port to said exhaust port;

a second passage extending through said housing connecting said input port to said outlet port;

a valve spool assembly movable with respect to said valve housing between an open condition and a closed condition, said second passage being closed and said first passage being open when said valve spool assembly is in said closed condition, said first passage being closed when said valve spool assembly is in said open condition;

a piston slidably disposed on said valve spool assembly, said piston movable between an open position and a blocked position, said piston being disposed in said blocked position to close said first passage when said valve spool assembly is first moved to said open condition; and

a third passage extending through said valve spool assembly connecting said input port to said outlet port, said third passage being open when said piston is in said blocked position to allow a specified flow of fluid between said input port and said outlet port such that fluid pressure increases in said outlet port at a rate slower than when said second passage is open, said piston moving from said blocked position to said open position to open said second passage when said fluid presure in said outlet port reaches a specified pressure.

11. The fluid control valve according to claim 10 wherein, said rate of increase of said fluid pressure in said outlet port is controlled by an orifice.

12. The fluid control valve according to claim 11 wherein, said orifice is adjustable.

13. The fluid control valve according to claim 10 wherein, said rate of increase of said fluid pressure in said outlet port is adjustable.

14. The fluid control valve according to claim 10 further comprising means for locking said valve spool in said closed position.