| 摘要 |
A digitally coded device for theft protection which can be applied to electrically operated solenoids as well as other forms of electrical apparatus and in particular the ignition coil of an internal combustion engine used to drive a motor vehicle, in which a thyristor (30) is connected in series with the primary winding (12) of the ignition coil (10). The device further includes a thumbwheel device (35) on which a code is manually set, an encoder transmitter (34) for converting the code to binary serial form, and a receiver decoder (32) for comparing the code set on a thumbwheel device (35) with a predetermined set code, the control gate of the thyristor (30) receives a positive potential which enables current to flow through the primary winding (12) of the ignition coil. If on the other hand there is disagreement, the coil is not enabled so no high secondary voltage can be generated to produce a spark. Also applicable to solenoid operated locks. <IMAGE> |
