PURPOSE: To supply an energy as a power to an intended equipment by a method wherein a strain energy stored in a spiral spring is directly taken out as the power.

CONSTITUTION: The stored energy makes one-way clutch 6a prevent a driving shaft 5 from reversing and the energy is secured in the stored state. To allow the stored energy in the spiral spring 4 to fed as an output, when an operation lever 12a of a change-over mechanism 12 is operated to press an end portion 12b downward, a pressure against a disc plate 7 is released, and a clutch shaft 7a is freely rotated in a ball bearing 8 integrally with the one-way clutch 6a and the driving shaft 5 therewithin. Accordingly, the strain energy stored in the spiral spring 4 is released, a decelerating mechanism 3 acts as an accelerating mechanism, the driving shaft 5 rotates in high speed, the output is fed from an output shaft 7b and the power can be supplied to the intended equipment.