To provide a generator capable of effectively reducing a cogging torque acting on a rotor.
In the small-sized generator 20 used in a pointer-type electronic clock 1, a stator 22 with an inner notch 225A, 226A for adjusting the cogging torque of the rotor 21 formed therein. A first magnetic circuit 100 passes through the stator 22 and a magnetic core 27 and a second magnetic circuit 101 has magnetic flux closed by the stator 22. The inner notch 225A, 226A, are formed in the inner peripheral edge of a rotor arrangement hole 230 within the range of an angle of ±45 degrees making the magnetic flux direction serve as the center in the center of rotation of the rotor 21 of the first magnetic circuit 100 with smaller magnetic resistance. Consequently, the cogging torque can be effectively reduced. In this way, for attaining a thinner timer device or the like, even by miniaturizing parts such as a rotational deadweight, a spiral spring, rotational startability of the rotor can be improved, and power generating efficiency in the small-sized generator can be improved.
| JP2007132788 | ELECTRONIC TIMEPIECE WITH ALARM AND ITS CONTROL METHOD |
| JPS5313467 | SOLAR BATTERY-DRIVEN TIMEPIECE |
Kanji Nakayama
Tsuyoshi Ishizaki