| 摘要 |
<p>The infra red heater for the cabin of motor vehicles operates from the vehicle batteries. To overcome the difficulty of producing an infra red emitting lamp running from low voltages the heater uses a parabolic ceramic emitter surface with embedded resistance heating wires. The infra-red radiation is then produced from the surface of the heated ceramic, removing the need for a lamp. The electric resistance wire is of heavy gauge tungsten to allow adequate current flow from a low voltage vehicle battery to produce sufficient heating power. The use of tungsten wire allows high wire temp. to be developed inside the ceramic. Thermal protection is provided by bi-metallic temp. sensors which cut-off the current if overheating occurs.</p> |
