| 摘要 |
An electrical resistance heating element comprises at least one heating conductor of positive-temperature-coefficient material having contact means on opposite surfaces; if more than one, they may be arranged in a row or in a stack. Electrical connection is made to the heating conductor or the row or stack through two substantially plane contact plates adapted to the layout of the heating conductor, row or stack and placed loosely upon opposite contact surfaces thereof. The components are held together elastically by securing means holding the edges of the contact plates. Two alternative forms of securing means are described, one consisting of a series of U-shaped clips of elastic material distributed along the edges of the element, the other consisting of strips of U-shaped cross-section which are made of material with soft elastic properties and extend along respective opposite edges of the heating element. The material of the latter may consist of thermally conductive silicone rubber; the U-shaped cross-section may be open at both ends or closed by a web at at least one end.
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