Claims
- 1. A heating apparatus comprises
- a plurality of lamps emissive of infra-red radiation and connectable to a power supply,
- and a user-operable control circuit for selecting any one of a number of different power settings, wherein said user-operable control circuit includes,
- a phase control circuit comprising a diac and a triac arrangement having a pre-determined conducting time to provide phase control of power supplied to the lamps and a resistor-capacitor network for determining said conducting time;
- at least one diode,
- a first switching means for selectively switching the lamps into a number of different interconnections,
- and second and third switching means for selectively switching the phase control circuit and said at least one diode respectively into at least one said interconnection thereby to attain a selected power setting.
- 2. Heating apparatus as claimed in claim 1 wherein said first switching means is adapted to interconnect said lamps into at least one of a series and parallel arrangement.
- 3. Heating apparatus as claimed in claim 1 wherein each of said lamps comprises a quartz envelope and a tungsten filament supported in said envelope.
- 4. Heating apparatus as claimed in claim 1 and further comprising an inner region accomodating said plurality of lamps, an outer region accomodating at least one further lamp, and further switching means to enable energisation of said plurality of lamps independently of said at least one further lamp.
Priority Claims (1)
Number |
Date |
Country |
Kind |
8422902 |
Sep 1984 |
GBX |
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Parent Case Info
This application is a continuation of application Ser. No. 769,731, filed Aug. 27, 1985, now abandoned.
US Referenced Citations (3)
Foreign Referenced Citations (2)
Number |
Date |
Country |
2118407 |
Apr 1971 |
DEX |
2132060 |
Jun 1984 |
GBX |
Continuations (1)
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Number |
Date |
Country |
Parent |
769731 |
Aug 1985 |
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