Feedback mechanism and valve positioner

A magnet holding member (131) is disposed in such a way as to move by interlocking with a driven shaft (A). First and second magnets (133, 134) are fixed to inner surfaces of the magnet holding member (131). The unlike poles of the first and second magnets (133, 134) face each other. A feedback lever (109) is swingably inserted into the space between the first magnet (133) and the second magnet (134). A third magnet (135) is provided in the feedback lever (109) in such a way that like poles of the first and second magnets (133, 134) and like poles of the third magnet (135) face each other. As a consequence of the above, the feedback lever (109) is held at position where the repulsive force due to the first and third magnets (133, 135) and the repulsive force due to the second and third magnets (134, 135) are in balance with each other. Due to such a configuration, it is possible to prevent bending, failure, etc. of the feedback lever, with no influence exerted on mounting accuracy between parts.