Flow control valve having adjustable piston for varying flow rate

• US 5,301,713 A
• Filed: 06/01/1993
• Issued: 04/12/1994
• Est. Priority Date: 06/01/1993
• Status: Expired due to Fees

• Current Assignee: Paul K. Skoglund
• Original Assignee: Paul K. Skoglund
• Inventors: Skoglund, Paul K.
• Primary Examiner(s): Nilson, Robert G.
• Application Number:
  US08/069,459
• Time in Patent Office: 315 Days
• Field of Search: 137/501, 137/504
• US Class Current: 137/504
• CPC Class Codes: G05D 7/0126 the sensing element being a piston or plunger associated with one or more springs
• CPC Class Codes: Y10T 137/7792 Movable deflector or choke

Abstract

A constant flow rate controller valve includes a piston spring biased towards the top of the valve. Fluid flowing into the valve increases the forces in the chamber above the piston, forcing the piston toward a valve seat. The piston is thus seated in the valve seat, blocking fluid flow to the outlet port. The forces on the piston in the chamber below the piston builds as flow goes through the piston until the forces in this chamber including the piston spring force is greater than the forces in the chamber above the piston. The piston then is lifted from the valve seat, and the pathway to the outlet orifice is opened. Fluid flows through the piston via the calibrated orifice. An equilibrium flow rate is reached by variation in the piston position based on the location of the movable seat which sets and maintains a constant differential pressure.

Claims

1. A valve;

a housing having an inlet and an outlet forming a flow passage through said housing;

a piston mounted in a bore in said flow passage, said piston dividing said bore into first and second chambers respectively communicating with said inlet and said outlet;

an orifice providing fluid flow from said inlet to said outlet;

spring means biasing said piston toward said inlet, said spring means providing a bias force that establishes a substantially constant pressure differential between said first chamber and said second chamber to enable substantially constant outlet flow at varied pressures;

a valve seat in between said piston and said outlet;

a pin slidably mounted in said piston, said pin aligned to seat and unseat with said valve seat; and

means for altering the position of said piston in said bore and with respect to said pin to adjust the fluid flow rate wherein said means for altering the position of said piston in said bore includes means for applying fluid pressure between said piston and said pin.

2. The valve of claim 1 wherein said means for altering the position of said piston in said bore is comprised of:

a fluid conduit between said piston and said pin; and

a fluid line communicating with said fluid conduit and with a fluid opening in said housing.

3. The valve of claim 2 wherein said means for altering the position of said piston in said bore is further comprised of:

a fluid pressure source communicating with said fluid line through said fluid opening.

4. The valve of claim 2 wherein said fluid conduit opens into said second chamber and said fluid line is located in said second chamber.

5. The valve of claim 1 wherein said orifice is axially off-set from said inlet.

6. The valve of claim 1 wherein said inlet and said outlet are axially aligned.

7. A valve for regulating fluid flow comprising:

a housing having an inlet and an outlet forming a flow passage through said housing;

a piston mounted in a bore in said flow passage, said piston dividing said bore into first and second chambers respectively communicating with said inlet and said outlet;

an orifice through said piston for fluid flow from said inlet to said outlet;

spring means biasing said piston toward said inlet, said spring means providing a bias force that establishes a substantially constant pressure differential between said first chamber and said second chamber to enable substantially constant outlet flow at varied pressures;

a valve seat in between said piston and said outlet;

a pin slidably mounted in said piston, said pin aligned to seat and unseat with said valve seat; and

means for altering the position of said piston in said bore and with respect to said pin to adjust the fluid flow rate, said means for altering the position of said piston including means for applying fluid pressure between said piston and said pin.

8. The valve of claim 7 wherein said means for altering the position of said piston in said bore is comprised of:

a fluid conduit between said piston and said pin; and

a fluid line communicating with said fluid conduit and with a fluid opening in said housing.

9. The valve of claim 8 wherein said means for altering the position of said piston in said bore is further comprised of:

a fluid pressure source communicating with said fluid line through said fluid opening.

10. The valve of claim 8 wherein said fluid conduit opens into said second chamber and said fluid line is located in said second chamber.

11. The valve of claim 7 wherein said orifice is axially off-set from said inlet.

12. The valve of claim 7 wherein said inlet and said outlet are axially aligned.

13. A valve for regulating fluid flow comprising:

a housing having an inlet and an outlet forming a flow passage through said housing;

a piston mounted in a bore in said flow passage, said piston dividing said bore into first and second chambers respectively communicating with said inlet and said outlet;

an orifice providing fluid flow from said inlet to said outlet;

spring means biasing said piston toward said inlet, said spring means providing a bias force that establishes a substantially constant pressure differential between said first chamber and said second chamber to enable substantially constant outlet flow at varied pressures;

a valve seat in between said piston and said outlet;

a pin slidably mounted in said piston, said pin aligned to seat and unseat with said valve seat; and

means for altering the position of said piston in said bore and with respect to said pin to adjust the fluid flow rate, said means for altering the position of said piston including a fluid conduit between said piston and said pin and a fluid line communicating with said fluid conduit and with a fluid opening in said housing.

14. The valve of claim 13 wherein said means for altering the position of said piston in said bore is further comprised of:

a fluid pressure source communicating with said fluid line through said fluid opening.

15. The valve of claim 13 wherein said fluid conduit opens into said second chamber and said fluid line is located in said second chamber.

16. The valve of claim 13 wherein said orifice is axially off-set from said inlet.

17. The valve of claim 13 wherein said inlet and said outlet are axially aligned.