TEMPERATURE ACTUATED FLOW RESTRICTOR

• US 20020145052A1
• Filed: 04/10/2001
• Published: 10/10/2002
• Est. Priority Date: 04/10/2001
• Status: Active Grant

• Current Assignee: Parker Intangibles LLC (Parker-Hannifin Corporation)
• Original Assignee: PGI International LTD (Parker-Hannifin Corporation)
• Inventors: Cessac, Kevin
• Granted Patent: US 6,450,412 B1
• Time in Patent Office: Days
• US Class Current: 236/48R
• CPC Class Codes: G05D 23/10 with snap-action elements

Abstract

A thermostat valve 10 is provided for controlling gas flow to an infrared catalytic heater 26. The thermostat valve includes a thermally responsive snap member 50, 64 positioned within a housing central flow path and moveable with respect to the housing between open and closed positions. An elastomeric seal 54 supported on the housing surrounds the central flow path and engages the snap member when in the closed position. A restricted flow path 58, 68 is provided in one of the housing and the snap disk for passing gas to the catalytic heater when the snap member is closed. The thermostat valve is relatively simple yet highly reliable.

Claims

1. A thermostat valve for controlling gas flow to a catalytic heater, comprising:

a housing having an inlet port, an outlet port, and a central flow path extending between the inlet port and the outlet port;

a thermally responsive snap member positioned within the housing central flow path and moveable with respect to the housing between an open position and a closed position;

an elastomeric seal supported on the housing and circumferentially surrounding the flow path through the housing for engagement with the snap member when in the closed position;

a restricted flow path in the housing in parallel with the central flow path through the elastomeric seal for passing gas to the catalytic heater when the snap disk is in the closed position; and

the snap member forming one or more passageways each positioned outwardly of the elastomeric seal for passing gas when the snap member is in both the open and closed positions.

2. A thermostat valve as defined in claim 1, further comprising:

a biasing member for biasing the snap member toward the closed position.

3. A thermostat valve as defined in claim 2, wherein the biasing member comprises an elastomeric material ring engaging a periphery of the snap member.

4. A thermostat valve as defined in claim 1, wherein the one or more passageways includes a plurality of through passageways through the snap member.

5. A thermostat valve as defined in claim 1, wherein the snap member has a disk shape.

6. A thermostat valve as defined in claim 1, wherein the one or more passageways are positioned between the snap member and the housing.

7. A thermostat valve as defined in claim 1, wherein the housing includes an inlet housing and an outlet housing each having threads for mating engagement.

8. A thermostat valve as defined in claim 7, further comprising:

a housing seal for sealing between the inlet housing and the outlet housing.

9. A thermostat valve as defined in claim 1, further comprising:

the housing including a threaded inlet port and a threaded outlet port;

a threaded inlet fitting for threaded engagement with the threaded inlet port; and

a threaded outlet fitting for threaded engagement with the threaded outlet port.

10. A thermostat valve as defined in claim 1, wherein the restricted flow path has a substantially uniform cross-section with a diameter less than 0.04 inches.

11. A thermostat valve for controlling gas flow to a catalytic heater, comprising:

a housing having an inlet port, an outlet port, and a central flow path extending between the inlet port and the outlet port;

a bi-material snap member positioned within the housing central flow path and moveable with respect to the housing between an open position and a closed position;

an elastomeric seal supported on the housing and circumferentially surrounding the flow path through the housing for engagement with the snap member when in the closed position;

a restricted flow path in the snap member radially inward of the elastomeric seal for passing gas to the heater when the snap member is in the closed position; and

the snap member forming one or more passageways each positioned radially outwardly of the elastomeric seal for passing gas when the snap member is in both the open and closed positions.

12. A thermostat valve as defined in claim 11, further comprising:

a biasing member for biasing the snap member toward the closed position.

13. A thermostat valve as defined in claim 12, wherein the biasing member comprises an elastomeric material ring engaging a periphery of the snap member.

14. A thermostat valve as defined in claim 11, wherein the one or more passageways includes a plurality of through passageways through the snap member.

15. A thermostat valve as defined in claim 11, wherein the housing includes an inlet housing and an outlet housing each having threads for mating engagement.

16. A thermostat valve as defined in claim 11, wherein the snap member has a disk shape.

17. A thermostat valve as defined in claim 11, wherein the one or more passageways are positioned outward of the snap member.

18. A thermostat valve as defined in claim 11, wherein the restricted flow path has a nominal diameter less than 0.04 inches.

19. A thermostat valve for controlling gas flow to a catalytic heater, comprising:

a housing having an inlet port, an outlet port, and a central flow path extending between the inlet port and the outlet port;

a thermally responsive snap disk positioned within the housing central flow path and moveable with respect to the housing between an open position and a closed position;

an elastomeric seal supported on the housing and circumferentially surrounding the flow path through the housing for engagement with the snap disk when in the closed position;

a biasing member for biasing the snap member toward the closed position;

a restricted flow path in one of the housing and the snap disk for passing gas to the catalytic heater when the snap disk is in the closed position; and

the snap member including one or more passageways each positioned radially outwardly of the elastomeric seal for passing gas when the snap member is in the open and closed positions.