| 摘要 |
PROBLEM TO BE SOLVED: To eliminate the necessity of increasing the entire length of a motor and reduce the thickness of a motor section, by installing a part of a rotatably supported frame and a sensor for detecting the position or rotating speed of the motor, in a space up to an end face of a stator winding which communicates with a recessed section of a rotor. SOLUTION: At an end face section of a rotor iron core 6a, 6b of a rotor 3, a cylindrical recessed section 21 which has a smaller inner diameter than an outer diameter of the rotor 3 are formed in parallel with a shaft 7 in a region where it may hardly influence the generation of torque of the rotor 3. In order to form the recessed section 21, the rotor iron core 6a, 6b is formed by stacking two kinds of iron plates, iron plates with their inner parts being cut and iron plates with their inner parts not being cut, and putting an annular permanent magnet 6c in between. The permanent magnet 6c has a high energy product, and therefore, even if it is thin, enough magnetic flux density can be obtained. In a space 22 formed in a step 11a of a frame 11 at the outside of a bearing 9, a sensor 23 for detecting the position or rotating speed of the rotor 3 is installed. |
