| 摘要 |
<p>An electric heating pad including a flexible thin film heating element (4) including two independent semiconductor circuits printed on an electrically insulating surfaces, laminated between overlying and underlying organic polyester sheets, the heating element being hermetically sealed in an outer organic polymer covering (6, 8) made of polyvinylchloride, polyethylene, or polyurethane. Thermostats (12a, 12b) are positioned directly over the printed circuits. A thermally conductive grease is applied between the thermostats and a polyester sheet to improve thermal conductivity. The independent circuits are connected in parallel by a multi-position switch (16), with each circuit being capable of being energized separately or in combination over the entire area of the pad.</p> |
