Abstract: A machine tool includes a first spindle, a second spindle, and a joining means for joining the axial ends of workpieces gripped by the spindles to form a joined workpiece. The machine tool further includes an electric servomotor for moving the first spindle in the direction intersecting the axis of the first spindle, a current value detection means for detecting the current value of the electric servomotor, and a misalignment detecting means for detecting misalignment of a first workpiece and a second workpiece in the joined workpiece, based on the current value detected by the current value detection means when the joined workpiece gripped by the two spindles is rotated.

Abstract: A machine tool and a control method for the machine tool, which determine the degree of misalignment during friction joint, are provided. The machine tool (an automatic lathe 1) includes: a first spindle 10 rotatably holding a first workpiece (a workpiece W1); a second spindle 20 arranged to face the first spindle and rotatably holding a second workpiece (a remaining workpiece W2); and a controller 40a, while rotating at least one of the first workpiece or the second workpiece, relatively moving the first spindle and the second spindle so as to get closer to each other and pushing a rear end portion of the second workpiece against a front end portion of the first workpiece to frictionally join the first and second workpieces. The controller has a misalignment amount detector detecting a misalignment amount s of the second workpiece with respect to the first workpiece during the friction joint.

Abstract: A machine tool includes a first spindle, a second spindle, and a joining means for joining the axial ends of workpieces gripped by the spindles to form a joined workpiece. The machine tool further includes an electric servomotor for moving the first spindle in the direction intersecting the axis of the first spindle, a current value detection means for detecting the current value of the electric servomotor, and a misalignment detecting means for detecting misalignment of a first workpiece and a second workpiece in the joined workpiece, based on the current value detected by the current value detection means when the joined workpiece gripped by the two spindles is rotated.

Abstract: A control device for a machine tool and a machine tool, for which settings of the number of vibrations per rotation become easy, is provided. The control device of the machine tool controls a relative rotation between a workpiece and a cutting tool and a relative reciprocal movement between the workpiece and the cutting tool in a feed direction to perform vibration cutting to the workpiece. The control device includes a control section for controlling a spindle headstock, a first tool post, and a second tool post, the workpiece W being installed on the spindle headstock, the first tool post being provided to be reciprocally movable along the feed direction with respect to the spindle headstock and installed with a first cutting tool for cutting the workpiece, and the second tool post being provided to be reciprocally movable along the feed direction with respect to the spindle headstock independently of the first tool post and installed with a second cutting tool for cutting the workpiece.

Abstract: A control apparatus for machine tool, in accordance with user set conditions, feeds a cutting tool in a feeding direction while reciprocatively vibrating the cutting tool, smoothly cuts a workpiece, and achieves a machined surface having an improved appearance. In a machine tool and a control apparatus thereof, a control means is configured to set the number of rotations of relative rotation and the number of vibrations of reciprocating vibration during one rotation of the relative rotation in accordance with a vibration frequency attributable to a cycle during which an operation instruction can be issued, and the control means includes adjusting means configured to adjust the number of rotations or the number of vibrations set by the control means.

Abstract: A control device for a machine tool and a machine tool, for which settings of the number of vibrations per rotation become easy, is provided. The control device of the machine tool controls a relative rotation between a workpiece and a cutting tool and a relative reciprocal movement between the workpiece and the cutting tool in a feed direction to perform vibration cutting to the workpiece. The control device includes a control section for controlling a spindle headstock, a first tool post, and a second tool post, the workpiece W being installed on the spindle headstock, the first tool post being provided to be reciprocally movable along the feed direction with respect to the spindle headstock and installed with a first cutting tool for cutting the workpiece, and the second tool post being provided to be reciprocally movable along the feed direction with respect to the spindle headstock independently of the first tool post and installed with a second cutting tool for cutting the workpiece.

Abstract: This invention provides a machine tool that, in addition to sequentially separating a chip generated from a workpiece in a reliable manner, improves the roundness of the finished workpiece and improves the visual appearance and roughness of a machined surface of the workpiece, and a control apparatus of the machine tool. A machine tool or a control apparatus thereof includes a vibration frequency setting unit for setting vibration frequency of the reciprocal vibration with respect to one relative rotation when machining a workpiece so that the intersections of paths of a cutting tool during forward movement and backward movement are dispersed on a circumferential surface of the workpiece.

Abstract: To provide a machine tool and a control device for the machine tool that can smoothly cut a workpiece while segmenting chips by feeding a cutting tool in a feed direction while reciprocally vibrating the cutting tool along the feed direction on the basis of a condition set by a user.

Abstract: A control apparatus for machine tool, in accordance with user set conditions, feeds a cutting tool in a feeding direction while reciprocatively vibrating the cutting tool, smoothly cuts a workpiece, and achieves a machined surface having an improved appearance. In a machine tool and a control apparatus thereof, a control means is configured to set the number of rotations of relative rotation and the number of vibrations of reciprocating vibration during one rotation of the relative rotation in accordance with a vibration frequency attributable to a cycle during which an operation instruction can be issued, and the control means includes adjusting means configured to adjust the number of rotations or the number of vibrations set by the control means.

Abstract: This invention provides a machine tool that, in addition to sequentially separating a chip generated from a workpiece in a reliable manner, improves the roundness of the finished workpiece and improves the visual appearance and roughness of a machined surface of the workpiece, and a control apparatus of the machine tool. A machine tool or a control apparatus thereof includes a vibration frequency setting unit for setting vibration frequency of the reciprocal vibration with respect to one relative rotation when machining a workpiece so that the intersections of paths of a cutting tool during forward movement and backward movement are dispersed on a circumferential surface of the workpiece.

Abstract: To provide a machine tool and a control device for the machine tool that can smoothly cut a workpiece while segmenting chips by feeding a cutting tool in a feed direction while reciprocally vibrating the cutting tool along the feed direction on the basis of a condition set by a user.