PURPOSE: To eliminate the installation of a plate to be detected over the entire railway line by disposing detecting coils at two positions isolated in a traveling direction in the specific size at the train side opposed to levitating coils.
CONSTITUTION: Detecting coils 12, 13 for detecting a magnetic field produced by a voltage inducted in a levitating coil are disposed at two positions on a train in which the distance between the centers of trains in traveling direction oppositely to a levitating coil 9 on the ground side is τ×n+τ/2 (where τ: pole pitch of levitating coil, and n: natural number). The coils 12, 13 are connected in a bridge together with a variable impedance 14 and a stationary impedance 15, and the differential voltage is outputted through an amplifier 16 and a waveform shaper 17 as a position signal. In this manner, a facility over the entire railway line such as a plate for detection can be eliminated.
KOJIMA TAKAHIKO
KOIKE SHIGEKI
HITACHI LTD
| JPS56157203A | 1981-12-04 |