Electric furnace
Abstract
Abstract An electric air heater is provided with a cabinet enclosing a heating chamber having top, bottom and sidewalls. The heating chamber houses an open-ended cylindrical heat exchanger positioned so as to absorb heat from a plurality of lamps mounted at the junctures of the sidewalls. A fan is provided to pump air from a cabinet air inlet into an air inlet in the bottom wall. The air is pumped into and around the heat exchanger, over the lamps and out an air outlet in the top wall. The cabinet is kept cool by passing the cool incoming air through a tortuous air flow ducts surrounding the heating chamber before the air flows into the chamber. The heat exchanger is provided with a plurality of inwardly directed ferrous rod members secured to the heat exchanger by a dome-shaped bronze weld.
Inventors
- 👤 Darrell W Covault
Bibliographic Details
Claims Analysis
Total Claims: 2References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-04-19 | 1974-10-19 | 1975-04-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-04-19 | 1978-10-19 | 1979-04-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-04-19 | 1982-10-19 | 1983-04-20 | $7700.00 | Window Closed / Lapsed |