| 摘要 |
PURPOSE:To enable accurate positional detection in a vehicle side, by such simple constitution that one guide line being laid along a running road is utilized. CONSTITUTION:Each of means P1, P2... for lowering the signal from an guide line 1 is one wherein the guide line 1 is laid so that a part thereof is allowed to cross a running road A at right angles and folded back plural times. The magnetic field generated from the guide line 1 is detected by a detection coil 2 and the detected level thereof is lowered near to zero at each point of the means P1, P2... on the running road. This signal lowering is detected by comparing a reference value being the output signal of a reference signal generating circuit 26 and the output signal of a rectifier circuit by a comparison circuit 25 and the detected signal is outputted to a counter circuit 27 which in turn counts the number of this detected signal. That is, the specific point of the running road A of a vehicle 11 is set to a positional reference point and the position (distance) from the reference point can be detected by the count number of the counter circuit 27. |
