FLOW CONTROL VALVE

• US 3,586,036 A
• Filed: 11/26/1969
• Issued: 06/22/1971
• Est. Priority Date: 11/26/1969
• Status: Expired due to Term

• Current Assignee: Alco Standard Corp. (Ricoh Company Limited)
• Original Assignee: Gene A. Barnes
• Inventors: Barnes, Gene A.
• Application Number:
  US04/880,284
• Time in Patent Office: 573 Days
• US Class Current: 137/486
• CPC Class Codes: G05D 7/0113 the sensing element acting as a valve
• CPC Class Codes: Y10T 137/7759 Responsive to change in rate of fluid flow
• CPC Class Codes: Y10T 137/7788 Pressures across fixed choke
• CPC Class Codes: Y10T 137/7791 Pressures across flow line valve

Abstract

Adjustable flow control valve maintaining a preselected constant flow rate with changing inlet pressures and viscosity of the fluid flowing through the valve. The valve includes a pilot control mechanism and a servocontrol mechanism. These mechanisms are in the form of diaphragms subjected to inlet pressure and spring loaded to bias the diaphragms against inlet pressure with a predetermined force. An orifice, the area of which may be preselected, conducts fluid from the inlet or upstream sides of the diaphragms to the downstream sides of the diaphragms. A higher spring acts on the servo diaphragm than on the pilot diaphragm. The diaphragms each have a valve as a part of the diaphragm. As inlet pressure increases the diaphragm valves will move toward seats against the forces of the springs loading the diaphragms and the pressure of the fluid on the downstream side of the pilot and servo diaphragms. The orifice is in the form of a contoured hole wiped by a thin metal cam, to cause a change in orifice area and change in flow, as required.

Claims

1. In a flow control valve, a valve body, an inlet into said valve body, an outlet from said valve body, means maintaining a substantially uniform flow of fluid from said inlet to said outlet, comprising fluid pressure operated pilot valve means, fluid pressure operated servo valve means, said valve means both being subjected to inlet pressure, a restricted orifice accommodating the flow of inlet fluid under pressure to counteract inlet pressure acting on said pilot valve means, and a passageway controlled by said pilot valve means accommodating the fluid flowing through said orifice to flow to the underside of said servo valve means and counteract the pressure acting on said servo valve means for discharge through said outlet under the control of said servo valve means.

2. The flow control valve of claim 1, wherein means are provided for varying the cross-sectional area of said orifice in accordance with a preselected flow of fluid to be delivered from the valve.

3. The flow control valve of claim 1, wherein the passageway from the underside of the pilot valve means to the underside of the servo valve means includes a valve seat cooperating with said pilot valve means to control the flow of fluid to the underside of said servo valve means, and wherein the outlet from the valve chamber includes a valve seat cooperating with said servo valve means for controlling the flow of fluid through said outlet in accordance with differences in pressure between inlet pressure and pressure on the underside of said servo valve means.

4. The flow control valve of claim 3, wherein spring means bias said pilot valve means and said servo valve means away from their respective seats.

5. The flow control valve of claim 4, wherein the spring means biasing the servo valve means away from its seat is stronger than the spring means biasing said pilot valve means away from its seat.

6. The flow control valve of claim 5, wherein means are provided for varying the cross-sectional area of said orifice in accordance with flow requirements.

7. A flow control valve of claim 6, wherein the means for varying the cross-sectional area of said orifice comprises a cam movable over said orifice in accordance with preselected desired pressure ranges.

8. The flow control valve of claim 5, wherein the pilot valve means includes a diaphragm subject to inlet pressure on its upstream side and having a valve on its downstream side, wherein the servo valve means includes a diaphragm subject to inlet pressure on its upstream side and having a valve on its downstream side, wherein spring means biases said pilot valve away from its seat, wherein spring means biases said servo valve away from its seat, and wherein the spring means biasing the servo valve away from its seat is heavier than the spring means biasing the pilot valve away from its seat.

9. The flow control valve of claim 8, wherein manually operable means are provided to vary the cross-sectional area of said orifice.

10. The flow control valve of claim 9, wherein the orifice comprises a flat orifice plate having an orifice leading therethrough, wherein means for varying the cross-sectional area of said orifice comprises a flat cam plate having an irregular peripheral surface movable over said orifice, wherein spring means biases said cam plate into engagement with said orifice plate, and wherein manually operable means are provided to rotatably move said cam plate to provide a preselected orifice area.

11. In a pressure and viscosity sensitive flow control valve, a valve body, an inlet into said valve body, an outlet from said valve body, a pilot chamber iN said valve body, a servo chamber in said valve body separated from said pilot chamber, a valve seat and passageway leading from said pilot chamber to said servo chamber, a valve seat and passageway leading from said servo chamber to said outlet, a pilot diaphragm subject to inlet pressure and defining a closure wall for said pilot chamber, a servo diaphragm subject to inlet pressure and defining a closure wall for said servo chamber, a pilot valve on said pilot diaphragm cooperating with said pilot valve seat, spring means biasing said pilot diaphragm away from said valve seat, a servo valve on said servo valve diaphragm cooperating with said servo valve seat, spring means biasing said servo valve away from said valve seat, and a restricted orifice controlling the flow of fluid to said pilot chamber and servo chamber and through said outlet under the control of said pilot and servo diaphragms.

12. The flow control valve of claim 11, wherein cam means adjustable from outside of said valve body is provided to vary the cross-sectional area of said restricted orifice and provide a preselected flow through said outlet.

13. The flow control valve of claim 11, wherein a passageway leads from the upstream sides of said pilot and servo diaphragms to said pilot valve chamber, wherein an orifice plate extends over said passageway and has a restricted orifice in registry therewith, wherein a cam plate abuts the top surface of said orifice plate, wherein a cam drive member reinforces said cam plate, wherein spring means engageable with said cam drive member press said cam plate in firm engagement with said orifice plate, wherein a manually adjustable member is provided to rotatably drive said cam drive member and provide a seat for one end of said spring, and wherein said cam drive member is turnable from the outside of said valve body to enable the cross-sectional area of said orifice to be preselected in accordance with a required flow of fluid through said outlet.