The purpose of the present invention is to provide a driving machine that fills (pressurizes) the inside of an air pressure chamber with air. The driving machine drives a stopper by the repulsive force of compressed air and comprises: a housing; a cylinder that is provided inside the housing; an air pressure chamber that is spatially connected to the cylinder; a piston that is provided so as to be able to move back and forth inside the cylinder; a blade that is attached to the piston and strikes a stopper; and a moving mechanism that reduces the volume of the air chamber or the inside of the cylinder by using a motor. The driving machine is configured to have a pressure accumulating mode in which the air pressure chamber is pressurized by the motor while being in a state in which the air chamber communicates with the outside and a striking mode in which the piston is caused by the motor to move from a bottom dead point to a top dead point inside the cylinder and then from the top dead point toward the bottom dead point, thereby driving the stopper.
