A drive machine which includes a housing, a motor disposed in the housing, a magazine which is attached to the housing and supplies a nail to a drive position, a plunger for driving the nail, a spring which impels and accelerates the plunger to the drive position by elastic force and a chain or belt which is driven by the motor to thus accumulate elastic energy in the spring. The chain has a projection which provides a first state where elastic energy is accumulated in the spring and a second state where the accumulated elastic energy is released.