Patent attributes
A press brake includes a ram to which an upper or lower tool can be attached; a movable ram driver; and a controller that controls the ram driver, wherein the ram driver includes a rotation/linear motion converter composed of a screw fixed to the ram and moves upward and downward as the ram moves upward and downward, and a nut screw-coupled with the screw; a drive rotation body arranged rotatably about a rotation axis of the nut; a first motor arranged in a fixed state; a first power transmitter that transmits rotation of the first motor to the nut at high speed and with low torque; a second motor arranged in a fixed state; a second power transmitter that transmits rotation of the second motor to the drive rotation body at low speed and with high torque; and a clutch provided between the nut and the drive rotation body.
