| 摘要 |
<p>PURPOSE:To simplify the structure of a brake gear and to electrically control braking power by using a piezo-electric element as a damping member and utilizing minute expansion and contraction produced by applying an electric field for damping. CONSTITUTION:In order to efficiently obtain a braking effect, a brake shoe 28 is adhered to a damping member 11 of a bimorph structure in which two sheets of piezo-electric material are sticked together, and when an electric field is applied to the bimorph 11, the forward end thereof displaces in the arrow direction, so that the brake shoe 28 contacts the outer peripheral surface of a brake drum 26, and such displacement is checked by the drum. The drum 26 is pressed by force corresponding to such checked displacement. The frictional force corresponding to the coefficient of friction between the shoe 28 and the drum 26 is damping power. This damping power can be controlled precisely by controlling the applied electric field by a variable voltage DC power source 20.</p> |
