| 摘要 |
<p>A time switch is used to operate an appliance after a preset time interval. It may operate more than one appliance and may be used for more than one time interval. The time switch has a graduated minute scale (13) and a disc (16) driven by a clock mechanism. The disc (16) has a rim (27) of magnetic material. A removable pointer (31) can be fitted to the rim (27) and set opposite a graduation of the scale (13) corresponding to the time interval required. The pointer (31) is also made of magnetic material and is secured by the rim (27). At the end of the interval, the pointer (31) operates a photocell. Other pointers similar to the first pointer (31) may be fitted to the rim (27) to obtain other time intervals independent of the first preset interval.</p> |
