Patent ID: 6474227
Filing Date: 2002-11-05
Classification: B30B

Abstract:
A method of controlling synchronous drive of a plurality of pressing machines, each of the pressing machines having a motor, a drive shaft to which a torque of a flywheel driven by the motor is transmitted through a clutch and a slide driven by the drive shaft so that a rotational position of the drive shaft of each of the pressing machines is synchronous each other, the method comprising:a first step of setting reference velocity information of each of the motors in the pressing machines; a second step of generating reference rotational-position information of each of the drive shafts, based on the reference velocity information; a third step of engaging the clutch of each of the pressing machines; and a fourth step of controlling drive of the motor in each of the pressing machines, wherein the fourth step carried out in each of the pressing machines comprising the steps of: detecting actual velocity information of the motor; detecting actual rotational-position information of the drive shaft; comparing the actual rotational-position information with the reference rotational-position information; compensating the reference velocity information into characteristic reference velocity information of each of the pressing machines, based on a result of the comparison; and controlling drive of the motor, based on the characteristic reference velocity information and the actual velocity information.