| 摘要 |
PURPOSE:To enhance conversion sensitivity by so supporting the armature of magnetic material fixed to one end of a cantilever as to make access to each pole piece constituting magnetic circuit by means of viscoelastic body. CONSTITUTION:When the stylus tip is in a neutral state, DC magnetic fluxes phi, phi' flow respectively in the yoles 13a and 13b and therefore no voltage is generated in the power generating coil 18a, 18b mounted to these yokes. Next, when the stylus tip displaces, the magnetic resistance between the armature 11 and yoke 13a decreases and therefore the magnetic flux phi of the yoke 13a increases to cause AC magnetic fluxes to flow and the magnetic flux phi' of the yoke 13b decreases to cause AC magnetic fluxes of opposite direction to flow, thereby inducing voltages in the power generating coils 18a, 18b respectively. As the stylus tip displaces in the reverse direction, power is generated in the direction opposite from the above. Hence, if the coils 18a, 18b are so push-pull-connected that these voltages are mutually applied, the output voltages are generated in terminals 17a, 17b, thereby enabling conversion sensitivity to be enhanced. |
