摘要 |
An electric current feeding to an electric heating unit designed for dissipating a fog formed on a glass window of a vehicle by its thermal effect. The apparatus has one fuse connected with an ignition switch and two fuses connected with input terminals of an electromagnetic relay having two contacts for connection with a heating unit in parallel. The electromagnetic relay is actuated by the ignition switch through an electric timer activated by a manual defogger switch. An electric current feeding system is provided for protecting the contacts of the electromagnetic relay from a short-circuit by melting or breakage by arranging the same such that the manual defogger switch, timer and relay are connected with the vehicle power source through one of the three fuses, respectively. Thereby the apparatus can be rendered entirely inoperative when any one of three fuses is blown, or the circuit connected therewith is disconnected.
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