Press machine, method of driving press machine, and industrial machine

In an industrial machine using a flywheel, in order to prevent increase in size of a driving motor, etc. and very freely control velocity of a load, an output shaft of a reduction gear set is connected to a load driving shaft, an input-shaft-sided gear of the reduction gear set is driven by a first motor, a differential mechanism is connected to the flywheel, the differential mechanism is configured such that the output shaft of the reduction gear set is connected to a carrier, rotational force inputted from the sun gear is transmitted to the flywheel and stored as energy while the stored energy is discharged to the sun gear and the carrier. Further, the sun gear of the differential mechanism is driven by a second motor, energy is stored by accelerating the flywheel using the second motor according to the rotational angle position of the load driving shaft, and then the load driving shaft is driven while compensating insufficient torque of the first motor by discharging the stored energy.