Modulating thermostat for gas oven burner

• US 6,149,065 A
• Filed: 10/28/1998
• Issued: 11/21/2000
• Est. Priority Date: 10/28/1998
• Status: Expired due to Fees

• Current Assignee: Burner Systems International Incorporated
• Original Assignee: Harper-Wyman Company
• Inventors: White, David B., White, Charles S.
• Primary Examiner(s): Lazarus, Ira S.
• Assistant Examiner(s): CLARKE, SARA SACHIE
• Application Number:
  US09/182,294
• Time in Patent Office: 755 Days
• Field of Search: 236/15 A, 236/68 B, 126/39 G
• US Class Current: 236/15.00A
• CPC Class Codes: F23N 1/007 using mechanical means F23N1/04 - F23N1/10 take precedence
• CPC Class Codes: F23N 2227/22 Pilot burners
• CPC Class Codes: F23N 2241/08 Household apparatus
• CPC Class Codes: F23N 5/027 using mechanical means F23N5/04 - F23N5/14 take precedence
• CPC Class Codes: F23N 5/06 using bellows; using diaphragms
• CPC Class Codes: F24C 3/087 in baking ovens
• CPC Class Codes: F24C 3/128 in baking ovens

Abstract

A modulating thermostat for a gas oven includes a body with supply, main and pilot passages. Feeder passages from the supply passage to the main and pilot passages provide a pilot gas flow for a pilot burner and a minimum combustion bypass flow to a main oven burner. The feeder passages are drilled along paths leading from mouths of the main and pilot passages and adjustment sleeves installed at the mouths adjust the gas flows for particular oven and fuel requirements. A temperature modulating valve assembly in the supply passage includes a valve member cooperating with a valve seat in the body to modulate gas flow and maintain an oven temperature set by rotation of a valve stem at the front of the thermostat. The thermostat is calibrated by rotating a sleeve accessible through the hollow stem at the front of the thermostat.

Claims

1. A modulating thermostat for supplying gas from a gas supply to an oven having a main burner, a pilot burner and a temperature sensor, said thermostat comprising:

a body having a front wall and a rear wall;

a supply passage extending between said front and rear walls and including an inlet section adapted to be connected to the gas supply and an outlet section;

a temperature responsive valve separating said inlet and outlet sections of said supply passage, said temperature responsive valve including a valve seat and a modulating valve member adapted to be connected to the oven temperature sensor;

main and pilot passages extending between said front and rear walls spaced from one another and from said supply passage and each having a mouth at said front wall;

a main burner outlet port in said rear wall adapted to be connected to the oven main burner and communicating with said main passage;

a pilot burner outlet port in said rear wall adapted to be connected to the oven pilot burner and communicating with said pilot passage;

an outlet passage extending from said outlet section of said supply passage to said main passage;

a bypass feeder passage extending from said inlet section of said supply passage to said main passage; and

a pilot feeder passage extending from said inlet section of said supply passage to said pilot passage;

said modulating thermostat being characterized by;

said main and pilot passages each extending along a single straight line from said front to said rear wall;

said bypass feeder passage extending in a single straight line beginning at said mouth of said main passage and extending to said inlet section of said supply passage; and

said pilot feeder passage extending in a single straight line beginning at said mouth of said pilot passage and extending to said inlet section of said supply passage.

2. A modulating thermostat as claimed in claim 1 further comprising bypass and pilot adjustment sleeves received in said mouths of said main and pilot passages for adjusting the flows from said bypass and pilot feeder passages into said main and pilot passages.

3. A modulating thermostat as claimed in claim 1, said body having a transverse wall extending between said front and rear walls and an inlet passage extending between said transverse wall and said inlet section of said supply passage.

4. A modulating thermostat as claimed in claim 3 further comprising a manually operated valve disposed in said inlet section for alternatively permitting and preventing flow from said inlet passage to said inlet section of said supply passage.

5. A modulating thermostat as claimed in claim 4, said manually operated valve including a valve plug in said inlet section and a stem coupled to said valve plug and projecting from said front wall.

6. A modulating thermostat as claimed in claim 5, said temperature responsive valve including a threaded adjustable coupling connected to said valve member and adapted to be connected to the temperature sensor for movement of said valve member relative to said valve seat in response to oven temperature changes;

and

a drive member carried by said valve plug and connected to said adjustable coupling for setting the oven temperature in response to rotation of said valve plug.

7. A modulating thermostat as claimed in claim 6, further comprising a calibration member interposed between said valve plug and said drive member for altering the position of said valve plug relative to the position of said drive member for calibrating the oven temperature setting.

8. A modulating thermostat as claimed in claim 7, said stem being hollow, and said calibration member being accessible through said hollow stem.

9. A modulating thermostat for supplying gas from a gas supply to an oven having a main burner, a pilot burner and a temperature sensor, said thermostat comprising:

a body having a front wall and a rear wall;

a supply passage extending between said front and rear walls and including an inlet section adapted to be connected to the gas supply and an outlet section;

a temperature responsive valve separating said inlet and outlet sections of said supply passage, said temperature responsive valve including a valve seat and a modulating valve member adapted to be connected to the oven temperature sensor;

main and pilot passages extending between said front and rear walls spaced from one another and from said supply passage and each having a mouth at said front wall;

a main burner outlet port in said rear wall adapted to be connected to the oven main burner and communicating with said main passage;

a pilot burner outlet port in said rear wall adapted to be connected to the oven pilot burner and communicating with said pilot passage;

an outlet passage extending from said outlet section of said supply passage to said main passage,

a bypass feeder passage extending from said inlet section of said supply passage to said main passage; and

a pilot feeder passage extending from said inlet section of said supply passage to said pilot passage;

said modulating thermostat being characterized by;

bypass and pilot adjustment sleeves received in said mouths of said main and pilot passages for adjusting the flows from said bypass and pilot feeder passages into said main and pilot passages; and

each said adjustment sleeve including a tubular portion received in the corresponding said mouth and an opening in said tubular portion aligned with said corresponding feeder passage by rotation of said adjustment sleeve.

10. A modulating thermostat as claimed in claim 9, said body being formed of aluminum and said tubular portions being formed of brass, each said tubular portion being secured in said corresponding mouth by axial compressive deformation of said tubular portion while said opening is spaced from said corresponding feeder passage.