Patent ID: 11931983
Assignee: NSK LTD.
Field: Machine tools (Mechanical engineering)
Classification: CPC B | IPC B

Claim 0:
1. A method of performing pressing on a workpiece using a press machine which comprises:
a frame having a reference axis,
a first die supported by the frame,
a second die supported by the frame, and configured to enable a retreating and an approaching movement with respect to the first die in an axial direction of the reference axis, and
a hydraulic cylinder configured to generate a force in a direction in which the second die approaches the first die,
the pressing method comprising:
performing radial direction positioning, which includes:
measuring, for each of multiple different radial deviations, which are deviations about a center axis in a radial direction between the first die and the second die, relative inclination amounts between the first die and the second die generated when pressing is performed on the workpiece by pressing the workpiece between the first die and the second die by causing the second die to approach the first die by pressing the second die against the first die using the hydraulic cylinder in a state in which the workpiece is disposed between the first die and the second die,
obtaining, using the measured relative inclination amounts for each of the multiple different radial deviations, a relationship between the measured relative inclination amounts and the multiple different radial deviations, and
radially positioning the first die and the second die so as to minimize the relative inclination amount between the first die and the second die, and

performing the pressing on the workpiece in a state in which the first die and the second die are disposed according to a set radial positions of the first die and the second die which was determined in the radial direction positioning process,
wherein the relative inclination amounts between the first die and the second die are measured using a laser displacement sensor.