| 摘要 |
PURPOSE:To enable a control signal for a damping means to be taken out with a sufficient level by a method wherein a signal detecting electrode is formed only at a part where the piezoelectric bimorph is actually bent. CONSTITUTION:The displacement detecting electrode 8 is formed extending over a prescribed length at the part where the piezoelectric bimorph is actually bent, that is, only at the part near a movable end where a part fixed to fitting member 5 with a fastening plate 6 is removed and a magnetic head 4 is fitted. When the piezoelectric bimorph 1 is bent due to the application of a control voltage or the disturbance, a stress caused by the bend appears on piezoelectric plates 1-1, 1-2 in the forms of a tensile stress and a compressive stress, the stresses turn up as signals corresponding to the bends of the piezoelectric bimorph on the detecting electrode 8 by the piezoelectric effect and taken out as the control signals with the sufficient level due to the nonexistence of a construction which causes the fall of the level. |
