JPS6418015A - Rotation detector - Google Patents

Abstract

PURPOSE:To enable the detection of a low consumption power at a high accuracy without lowering an output, by arranging a magnetosensitive sensor to have magnetosensitive elements placed with magnetic poles set at an interval of roughly 1/4 thereof in the same polarity and jump-connected in series to form one side of a detection circuit while grouping those performing the resistance changing in the same phase as one set. CONSTITUTION:Eight magnetosensitive elements A-H as indicated by Fig. (a) are arranged as opposed to one another on a plane with magnetic poles of the same polarity at an interval lambda of almost 1/4 as magnetized on an FG magnet 5. Sets of magnetosensitive elements A, C, E and G and B, D, F, H receive magnetic fields in the direction roughly vertical to the plane or in the direction of the plane separately as indicated by the arrow and the resistance thereof remains unchanged or decreases. These sets are built each reciprocating as indicated by a wire pattern of Fig. (b), jump-connected in series to form a bridge circuit in Fig. (c). The sets of A and C, F and H, B and D and E and F are connected to each other in series per set between a power source Vcc and the ground G. Then, an FG output is obtained indicating the state of rotation from an intermediate potential difference between midpoints x and y.