| 摘要 |
PURPOSE:To enable comfortable air draft by constituting the air draft pattern of a ceiling fan so that the length of one cycle is more than 300 seconds and the number of changes per cycle is more than 32 so as to make the power spectrum of the wind velocity in inverse proportion to the frequency. CONSTITUTION:A rotation number switching circuit 2 switches the number of motor rotation by changing voltage applied to a motor 1. The rotation number control circuit 3 controls the rotation number switching circuit 2 so that is becomes the rotation number of the motor stored inside, and after the rotation number of the motor 1 is kept for a certain period of time, the rotation number and the duration are sequentially changed so that the rotation number of 32 per cycle and the duration are changed, and wind velocity change pattern with more than 300 seconds per cycle is repeated for air draft. By this, the power spectrum of the wind velocity is made in inverse proportion to the frequency, and air can be blown with excellent comfortable feeling. |
