| 摘要 |
PURPOSE:To simplify the constitution of the long-time timer and vary a set value by providing a display means which decides on the rotational state of the speed reduction shaft of a small-sized synchronous electric motor to the speed reduction gear. CONSTITUTION:An AC power source 1 supplies electric power and a power source synchronizing signal to a switching circuit 2, and electric power having an accurate number of cycles is applied to the small-sized synchronous electric motor 3 on the basis of the power source synchronizing signal. In this case, the circuit 2 sums a signal on the basis of the power source synchronizing signal to generate a reference time interval. Then, the electric motor 3 rotates gradually and its rotation is reduced in speed by a speed reduction gear 4 and transmitted to the speed reduction shaft 5 and a display disk 6. The timer of this constitution is fitted to an equipment part 10 and the rotational state of the display disk 14 is observed through a display window 16. The set value of timer time is easily varied by turning forcibly a know fitted to the shaft 13. |
