Automatic flow control valve

• US 5,524,670 A
• Filed: 10/21/1994
• Issued: 06/11/1996
• Est. Priority Date: 10/21/1994
• Status: Expired due to Term

• Current Assignee: Taco, Inc.
• Original Assignee: Taco, Inc.
• Inventors: Castle, Robert W.
• Primary Examiner(s): Hepperle, Stephen M.
• Application Number:
  US08/328,579
• Time in Patent Office: 599 Days
• Field of Search: 137/504
• US Class Current: 137/504
• CPC Class Codes: G05D 7/0133 within the flow-path
• CPC Class Codes: Y10T 137/7792 Movable deflector or choke

Abstract

An automatic flow control valve for maintaining a predetermined output flow rate in response to a varying pressure differential across the valve has an orifice element, an occluding element and a spring each placed at least partially within a valve housing. The orifice element has a fluid port at a fixed and predetermined distance from an alignment end of the orifice element. The occluding element has an occluding region at a fixed and predetermined position relative to an alignment end of the occluding element. The spring extends along a longitudinal axis of the valve housing and the length of the spring in the absence of fluid flow is predetermined. In use, fluid flows longitudinally between the fluid port and the alignment end of the occluding element. This causes the alignment end of the orifice element to be aligned with one end of the compression spring and the alignment end of the occluding element to be aligned with a second end of the spring. This results in a predetermined alignment of the fluid port with the occluding region. In addition, the occluding element and first orifice element are shaped and positioned to move axially relative to one another in response to a pressure differential across the fluid port of the first orifice element, causing the occluding region to move past the fluid port to vary the occlusion of the fluid port. There results a predetermined relationship between pressure differential and occlusion of the fluid port.

Claims

1. An automatic flow control valve for maintaining a predetermined output flow rate in response to a varying pressure differential across the valve, comprising

a hollow housing for containing fluid flow along a longitudinal axis;

a compression spring disposed at least partially within the housing, the compression spring extending along the longitudinal axis and having first and second ends, a separation between the first end and the second end in the absence of fluid flow being predetermined;

a first orifice element disposed at least partially inside the housing, the first orifice element having an alignment end and a fluid port through which fluid flows during operation of the valve,

the alignment end being configured to be aligned, when fluid is flowing through the valve, with the first end of the compression spring,

the position of the fluid port relative to the alignment end being fixed and predetermined;

an occluding element disposed at least partially within the housing, the occluding element having an alignment end and an occluding region,

the alignment end being configured to be aligned, when fluid is flowing through the valve, with the second end of the compression spring,

the position of the occluding region relative to the alignment end being fixed and predetermined;

the occluding element, first orifice element, and compression spring being configured so that fluid flows longitudinally between the fluid port and the alignment end of the occluding element;

the occluding element and first orifice element being shaped and positioned to move axially relative to one another in response to a pressure differential across the fluid port of the first orifice element, and thereby to move the occluding region past the fluid port to vary the occlusion of the fluid port;

the housing, first orifice element, and occluding element being configured so that, when fluid flows through the valve and creates a pressure difference across the fluid port, and the first end of the compression spring is aligned with the alignment end of the first orifice element, and the second end of the compression spring is aligned with the alignment end of the occluding element, there is thereby a predetermined alignment of the fluid port with the occluding region, and a predetermined relationship between pressure differential and occlusion of the fluid port,

wherein said housing comprises a cartridge formed of a sheet metal disposed in a generally cylindrical shape, said sheet metal being bent in radially at each end of the cartridge.

2. The valve of claim 1 wherein the alignment end of the first orifice element has a generally planar region, one bent end of said cartridge being bent around the generally planar region of the alignment end of said first orifice element.

3. The valve of claim 1 wherein the alignment end of the occluding element has a generally planar region, one bent end of said cartridge being bent around the generally planar region of the alignment end of the occluding element.

4. An automatic flow control valve for maintaining a predetermined output flow rate in response to a varying pressure differential across the valve, comprising

a hollow housing for containing fluid flow along a longitudinal axis;

a compression spring disposed at least partially within the housing, the compression spring extending along the longitudinal axis and having first and second ends, a separation between the first end and the second end in the absence of fluid flow being predetermined;

a first orifice element disposed at least partially inside the housing, the first orifice element having an alignment end and a fluid port through which fluid flows during operation of the valve,

the alignment end being configured to be aligned, when fluid is flowing through the valve, with the first end of the compression spring,

the position of the fluid port relative to the alignment end being fixed and predetermined;

an occluding element disposed at least partially within the housing, the occluding element having an alignment end and an occluding region,

the alignment end being configured to be aligned, when fluid is flowing through the valve, with the second end of the compression spring,

the position of the occluding region relative to the alignment end being fixed and predetermined;

the occluding element, first orifice element, and compression spring being configured so that fluid flows longitudinally between the fluid port and the alignment end of the occluding element;

the occluding element and first orifice element being shaped and positioned to move axially relative to one another in response to a pressure differential across the fluid port of the first orifice element, and thereby to move the occluding region past the fluid port to vary the occlusion of the fluid port;

the housing, first orifice element, and occluding element being configured so that, when fluid flows through the valve and creates a pressure difference across the fluid port, and the first end of the compression spring is aligned with the alignment end of the first orifice element, and the second end of the compression spring is aligned with the alignment end of the occluding element, there is thereby a predetermined alignment of the fluid port with the occluding region, and a predetermined relationship between pressure differential and occlusion of the fluid port,

wherein the orifice element comprises a cup disposed at one longitudinal end of the housing, the fluid port being disposed on a cylindrical wall of the cup, and

further comprising a second orifice element, the second orifice element comprising a second cup, the first cup being nested within the second cup, the second cup having a fluid port disposed on a cylindrical wall of the second cup, an overlap between the fluid port on the first cup and the fluid port on the second cup defining an effective fluid port through which fluid flows into the valve.

5. The valve of claim 4 wherein the first cup is nested within the second cup in a tight coaxial fit, a rotation of the second cup relative to the first cup controlling an area of the effective fluid port.