Patent ID: 6742422
Filing Date: 2004-06-01
Classification: B23Q,G05B,Y10T

Abstract:
A numerically controlled lathe having: a first head stock and a second head stock arranged so as to be opposed to each other; a first main shaft supported by the first head stock and a second main shaft supported by the second head stock; a tool rest including tools used to machine workpieces grasped by the first main shaft and the second main shaft; and a numerical control device which controls rotation of the first main shaft, rotation of the second main shaft and relative movement of the tool rest with respect to the first head stock or the second head stock,the numerically controlled lathe comprising: a first tool rest to which one or both a first tool used to machine the workpiece grasped by the first main shaft and a second tool used to machine the workpiece grasped by the second main shaft can be attached and which can move in the direction of a Z1 axis parallel to a main shaft axial line of the first main shaft and the direction of an X1 axis orthogonal to the Z1 axis without restraint; a second head stock which can move in the direction of an X3 axis parallel to the X1 axis of the first tool rest and the direction of a Z3 axis parallel to the Z1 axis without restraint; a second tool rest to which one or both of a third tool used to machine the workpiece grasped by the first main shaft and a fourth tool used to machine the workpiece grasped by the second main shaft can be attached and which can move in the direction of a Z2 axis parallel to a main shaft axial line of the first main shaft and the direction of an X2 axis orthogonal to the Z2 axis without restraint; and a control device which includes a first control system which controls movement of the fist tool rest in the direction of the X1 axis and movement of the same in the direction of the Z1 axis, a second control system which controls movement of the second head stock in the direction of the X3 axis and movement of the same in the direction of the Z3 axis, and a third control system which controls movement of the second tool rest in the direction of the X2 axis and movement of the same in the direction of the Z2 axis, the first control system, the second control system and the third control system performing superposition control of movement of a pair of the X1 axis and the X3 axis, superposition control of movement of a pair of the X3 axis and the X2 axis, superposition control of movement of a pair of the Z1 axis and the Z3 axis and superposition control of movement of a pair of the Z3 axis and the Z2 axis in accordance with each combination of three tools in the tools T1 to T4 used to machine the workpiece W1 and the workpiece W2.