Electrothermal furnace control
Abstract
Abstract APPARATUS FOR CONTROLLING THE OPERATION OF A FURNACE HAVING AN ELECTRICALLY ENERGIZABLE FUEL VALVE WHICH, WHEN ENERGIZED, SUPPLIED FUEL TO THE FURNACE BURNER. AN IGNITION CIRCUIT GENERATES RECURRENT SPARKING, WHEN ENERGIZED, UPON THE DEMAND OF A THERMOSTAT, AND CEASES TO GENERATE SPARKING AFTER IGNITION OF THE FUEL. A TRIAC IS CONNECTED FOR ENERGIZING THE FUEL VALVE. A TRIGGERING CIRCUIT FOR THE TRIAC CAUSES TRIGGERING THEREOF ONLY IF THE IGNITION CIRCUIT GENERATES SPARKING. A THERMISTOR PREVENTS TRIGGERING OF THE TRIAC IF HEATED ABOVE A PREDETERMINED THRESHOLD. MEANS FOR HEATING THE THERMISTOR IS ENERGIZED TO CAUSE HEATING THEREOF WHEN THE IGNITION CIRCUIT GENERATES SPARKING, THE THERMISTOR REQUIRING A PREDETERMINED HEATING TIME INTERVAL TO REACH ITS THRESHOLD TEMPERATURE CAUSING TERMINATION OF TRIGGERING OF THE TRIAC IF THE FUEL IS NOT IGNITED WITHIN THIS INTERVAL.
Inventors
- 👤 Hans G Hirsbrunner
Bibliographic Details
Claims Analysis
Total Claims: 0References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-02-15 | 1974-08-17 | 1975-02-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-02-15 | 1978-08-17 | 1979-02-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-02-15 | 1982-08-17 | 1983-02-16 | $7700.00 | Window Closed / Lapsed |