Patent ID: 9722478
Date: 2017-08-01
CPC Classifications: H02K

Claim:
1. A stepping motor comprising: a rotor which comprises a rotation shaft and a permanent magnet on an outer peripheral face of the rotation shaft; a fixed body which comprises a cylindrical stator provided with a plurality of pole teeth that are disposed in a circumferential direction so as to face an outer peripheral face of the permanent magnet; an urging member which urges the rotor toward one side in a motor axial line direction; a supported face of the rotor which faces the one side in the motor axial line direction; and a support face of the fixed body which slidably supports the supported face of the rotor on the one side with respect to the supported face; wherein when a first sliding load which is a total sliding load applied to the rotor is “Ta”, a detent torque acted on the rotor is “Td”, and a dynamic torque acted on the rotor by the stator is “Te”, the first sliding load “Ta”, the detent torque “Td” and the dynamic torque “Te” satisfy a relationship shown by the following expression: