| 摘要 |
PURPOSE:To save the cost of equipment by automatically releasing resonance circuit short-circuiting of the second ground element without the necessity for a track circuit condition, in the case of a vehicle control device of variable frequency type having the two ground elements arranged with a space separated from each other. CONSTITUTION:Two ground elements 61, 62 are arranged with a speed check interval of a space l1, and the first ground element 61 is connected to a transmit ting circuit 63 and a receiving circuit 64 through a matching device 65 with a check signal applied to the first ground element 61 from the transmitting circuit 63. While in the receiving circuit 64, when the check signal can not be received, the first contact condition is output, and in the fixed point of time in which the point of time, next the check signal is placed receivable from when it is placed not receivable, serves for the reference, the second contact condition is outputted. When an on-vehicle element 41 is coupled to the first ground element 61, suppression is applied to the check signal by a normally oscillating frequency signal of an oscillating circuit 42 with the first contact condition established, and a resonance circuit is constituted while released by the second contact condition. |
