Patent ID: 9372063
Filing Date: 2016-06-21
CPC Classification: G01B,G01D

Claim Text:
1. A position sensing device for detecting a position of a detection object that moves relative to a reference member, the position sensing device comprising: a first magnetic flux transmission unit having a long shape and provided on one of the reference member or the detection object, the first magnetic flux transmission unit being formed by stacking a plurality of first thin boards in a board thickness direction, the plurality of first thin boards being made from magnetic material; a second magnetic flux transmission unit having a long shape and provided on the one of the reference member or the detection object, the second magnetic flux transmission unit being formed by stacking a plurality of second thin boards in the board thickness direction, the plurality of second thin boards being made from magnetic material, the board thickness direction of each of the plurality of second thin boards being parallel with the board thickness direction of each of the plurality of first thin boards, and a gap space being defined between the first and second magnetic flux transmission units; a first magnetic flux generation unit disposed at a position between one end of the first magnetic flux transmission unit and one end of the second magnetic flux transmission unit; a second magnetic flux generation unit disposed at a position between other end of the first magnetic flux transmission unit and other end of the second magnetic flux transmission unit; a flux density detection unit outputting a signal according to a density of a magnetic flux passing therethrough; a first concave region receding from one surface of each of the plurality of first thin boards in the board thickness direction; and a first convex region protruding from other surface of each of the plurality of first thin boards in the board thickness direction, and having a corresponding shape and position with the first concave region, wherein the flux density detection unit is disposed on an other of the reference member or the detection object, and is movable within the gap space along a gap space longitudinal direction relative to the one of the reference member or the detection object, the first magnetic flux transmission unit is formed by engaging the first convex region with the first concave region of each of the plurality of first thin boards, a movable range within the gap space, in which the flux density detection unit moves relative to the first magnetic flux transmission unit and the second magnetic flux transmission unit, is defined as a detection range, and the first concave region and the first convex region are disposed outside of the detection range.