| 摘要 |
<p>An electric timer to determine the duration of use of electrical machines and equipment, and determine the amount of energy consumed, has a multiposition switch (B) driven by a rotary knob. It also has an electromagnetic switching unit made up of an electrical coil (A1) connected to a contact (X1) of the switch (B) and to another contact (A3) connected to mains. A lever (D1) with an armature (A4) which can be displaced by the coil (A1) when energised, is in contact with a ratchet (G) which is part of the clock mechanism (D5). The device is operated by energising the coil (A1) which rotates the lever (D1) for a time given by the clock mechanism (D5). During this time, the mains (S) is connected to the heating elements (R1, R2) of the equipment.</p> |
