摘要 |
A method for sensing with a high accuracy a single part, at which electromagnetic characteristics of a member to be sensed are changed, and for obtaining the output whose waveform is of a narrow peak width, and the device thereof. For this purpose, four electromagnetic sensing elements (10A-10D) are so aligned that when the two elements (10A, 10B) are simultaneously in the positions just over a protruding part (16) where electromagnetic characteristics are changed, the other two elements (10C, 10D) are in the positions just over a recessed part (18). Further, the mutually opposing two arms of a bridge circuit (30) are connected with one of the electromagnetic sensing elements (10A, 10B) and one of the elements (10C, 10D) respectively. Thereby, a single output having a waveform corresponding to the part at which the electromagnetic characteristics are changed is sensed. <IMAGE> <IMAGE> |