| 摘要 |
PURPOSE:To aim at the protection of a circuit, the shortening of a circuit wire, lightweightiness and the promotion of commonability for the whole vehicle by connecting a PTC element to a circuit connecting the power supply and load of an automobile in series, and regulating the voltage to be added to the load due to the voltage drop. CONSTITUTION:Two PTC elements 9 and 9' are installed in a circuit wire 1 of both symmetrical head lamps 2 and a relay 5. A control circuit consisting of a fusible link 4, the relay 5 and the PTC elements 9 and 9' is assembled in an electric connection box 3. In this connection, load resistance in this circuit is larger enough than the resistance value of a steady state of the PTC element 9. Now, in a load circuit of the head lamp or the like, a voltage drop is caused by way of lengthening the circuit wire and thereby deterioration in a bulb is prevented from occurring, so that wire length is determined by an actual car. Since the PTC element 9 has a fuse function, the circuit is interrupted in substance at a time when an overcurrent flows in the circuit wire 1. In addition, as it has a voltage drop function in the steady state, this circuit wire 1 can be set to the shortest length as long as necessary for the wiring alone. |
