| 摘要 |
PURPOSE:To produce comfortable currents of air similar to the natural wind, by changing the speed of rotation of an electric fan periodically as different from the conventional arrangements in which the speed of rotation of the fan is kept constant. CONSTITUTION:A motor 1 has a rated speed of rotation of about 1,000rpm. A spinner 3 transmits rotation of the motor 1 to blades 2, which are turned when a pin 4 fixed to the spinner 3 comes into engagement with a recess 5 formed in a turning shaft 11 for the blades 2. The turning shaft 11 for the blades 2 is always urged forward by a brake plate 6 which is subjected to a biasing force of a spring 7. With such an arrangement, when the pin 4 comes into engagement with the recess 5 and the blades 2 begin to rotate, the blades 2 is retracted by reaction against the force of the spring 7, so that the spinner 3 comes out of engagement with the turning shaft 11. Thereupon, a switch 8 is turned OFF, so that the motor 1 is stopped. However, the turning shaft 11 comes again into engagement with the spinner 3 by the biasing force of the spring 7, so that the fan again begins to feed currents of air. |
