| 摘要 |
<p>A floor covering contains electrically conductive threads or wires, each of which extends over a considerable length of the fabric. Each thread along one of the edges of the floor covering is arranged so that a signalling device can be connected to it, and the conductors in separate lengths can also be attached continuously. The conductive threads, together or separately may form part of a high frequency resonance circuit, the capacity of which alters when a body comes into its proximity. There are no contacts to be closed, and any breakage of the threads is signalled immediately. The carpeting can be fitted in banks, museums, in halls and doorways, etc. so that the approach of any individual can be signalled immediately. The conductive threads, wires, strips, etc. may be woven into the carpet, so that they cannot be removed from it.</p> |
