Patent ID: 7061231

Claim:
A displacement measuring device provided with a displacement sensor constituted in such a manner that an output of the displacement sensor is varied in correspondence with a variation of relative position with respect to an object to be detected for detecting the object on the basis of the variation of the output, wherein a sensor set is disposed, which includes a pair of the displacement sensors arranged oppositely facing each other so as to interpose the object between them; wherein each of the displacement sensors in the sensor set is constituted in such a manner that an excitation coil and a detection coil are respectively wound around and mounted on a core body on the same axis; wherein one of the excitation coil and the detection coil is mounted on a center core part disposed at a generally center portion in an axial direction of the core body and the other of the excitation coil and the detection coil is mounted on a pair of axial end core parts respectively, which are disposed at both end portions in an axial direction of the core body; wherein the axial direction of the core body is disposed in a generally same direction as a varying direction of relative position with respect to the object; wherein one of the pair of axial end core parts and the object are approached to or separated from each other while opposing to each other, further wherein the width dimension of the axial end core parts, in a direction perpendicular to an axial direction of the axial end core parts, are formed narrower than a width dimension of the center core part; and wherein engaging flange parts protruding in a widthwise direction are respectively provided at respective boundary portions between the center core part and the pair of axial end core parts; and winding positions of the excitation coil and the detection coil are restricted at a prescribed position by the respective engaging flange parts; and further comprising a comparison metal body arranged so as to oppose the axial end core part which is positioned on an opposite side of the axial end core part facing the object to be detected.