Over temperature limiting scheme by reducing gas pressure
AssigneeHoneywell International Inc.
InventorDouglas D. Bird
Life of this patent
Estimating the term…
Abstract
An apparatus for and method for protecting the electronic circuitry within a gas appliance. The electronic circuitry is arranged on a circuit board. A temperature sensor, located on the circuit board is periodically read to determine the current temperature. If the current temperature exceeds a first predetermined value, a microprocessor commands a stepper motor to reduce the input fuel pressure to the main burner. If the current temperature is within an acceptable range, the microprocessor permits the user to increase main valve outlet pressure.
Claims20
In a gas appliance having a flame produced by a main burner wherein said flame of said main burner is controlled by a main valve, the improvement comprising:
- a. an electronic circuit coupled to said main valve which controls the pressure of fuel delivery from said main valve;
- and
- b. a temperature sensor responsively coupled to said electronic circuit whereby said pressure is reduced if said temperature sensor determines a temperature greater than a first predetermined value.
An apparatus comprising:
- a. A gas inlet;
- b. A gas outlet;
- c. A valve having a variable fuel outlet pressure interposed between said gas inlet and said gas outlet;
- d. A temperature sensor, and
- e. An electrical device responsively coupled to said temperature sensor and said valve which controllably varies said pressure from a first non-zero value to a second non-zero value in response to temperature sensed by said temperature sensor.
A method of facilitating protecting electronic circuitry from overheating within a gas appliance having a valve with an adjustable fuel pressure comprising:
- a. periodically measuring the temperature at a circuit board containing said electronic circuitry;
- b. decreasing said pressure if said temperature exceeds a first predetermined value;
- and
- c. increasing said pressure if said temperature exceeds a second predetermined value.
An apparatus comprising:
- a. Means for supplying a gaseous fuel;
- b. Means for determining temperature;
- and
- c. Means responsively coupled to said supplying means and said determining means for electrically changing said flow is response to temperature sensed by said determining means.
Dependencies are inferred from the claim text.