Abstract: A timer comprising a time body which has an operating shaft capable of angularly rotating around an axis thereof from an original position, and outputs a continuous electrical signal only for a period of time during which the operating shaft returns from a desired angular position to the original position after the operating shaft has been rotated from the original position to the desired angular position, a knob provided at one end of the operating shaft, a push button capable of being pressed to a predetermined distance, and driving device for rotating the operating shaft from the original position by an angle corresonding to a distance to which the push button is pressed.