Patent ID: 6153952
Filing Date: 2000-11-28
Classification: F02D,H02K

Abstract:
A DC torque motor comprising:a stator with a coil wound around a portion thereof, the stator having a generally U-shape and having arms with end portions facing each other and having magnetic pole sections arranged thereon; a needle surrounded by the end portions of the stator, being rotatably supported, and including permanent magnets attached thereto, so that the needle can be rocked within a predetermined working angle range; wherein a portion of the arms of the stator has a section area A smaller than that of the magnetic pole sections, the stator is formed of a material having a saturation magnetic flux density B, and the section area A satisfies the condition that the product of A and B is smaller than the sum of (i) a magnetic flux quantity which occurs when an electric current flows in the coil and (ii) a maximum permanent magnetic flux quantity generated by the permanent magnets within the working angle range.