摘要 |
A radiant electric heater (10) includes a layer of microporous thermal insulation (16) in a metal dish (12) and a peripheral wall (18) of ceramic fibre. A circular tungsten-halogen heating lamp (22) is supported in the dish above the insulation by its ends and by a protrusion (46) extending from the silica envelope (26) of the lamp. The protrusion extends sideways and is clamped between the insulation and the peripheral wall, and comprises a sealed exhaust tube used to evacuate and back-fill the lamp during its manufacture. Downwardly extending protrusions (120, 718) may be used instead of or in addition to sideways ones. A ridge (48) of the insulating material may also be provided, projecting up to engage with the underside of the lamp. This ridge may cooperate with the protrusion or with a clip (614) extending above the lamp to retain the lamp in position.
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