| 摘要 |
PROBLEM TO BE SOLVED: To provide a stepping motor, in which the thickness of permanent magnets in the rotating shaft direction is accurately set up so that desired torque can be secured. SOLUTION: This stepping motor 3 is provided with a rotor 34, having permanent magnets 35 formed in a cylindrical shape and with a stator 31, having field windings 33 and a yoke 32 excited by the field windings 33. The yoke is configured so as to surround the outside circumference of the permanent magnets 35 via the air gap G. The thickness T1 of the permanent magnets 35 in the rotating shaft direction is set up at a predetermined ratio to the thickness T2 of the yoke 32, in the direction of the rotating shaft of the rotor 34. The upper- and lower-limit values of the thickness T1 of the permanent magnets 35 are determined so that the rotor 34 can turn a load, having the desired moment of inertia at desired angular velocity, and the thickness T1 of the permanent magnets 35 is set to be between the upper- and lower-limit values. COPYRIGHT: (C)2008,JPO&INPIT
|
