Abstract: A highly convenient machine tool system is provided. An NC lathe as an example of the machine tool system includes a first tool post to which a first tool for machining a workpiece is attached, a numerical control unit adapted to control a movement of the first tool post according to a numerical control program, and a scanner adapted to measure a position and a shape of the first tool attached to the first tool post brought to a predetermined position under control of the numerical control unit.

Abstract: A lathe system includes a spindle capable of gripping a bar and moving back and forth in an axial direction of the bar and a tool post to which a first tool is attached. The lathe system can manufacture a plurality of products having an identical shape from the bar by repeating a machining of the bar, a cutting off of a machined portion of the bar, and a grip change by the spindle, the grip change by the spindle comprising releasing the bar, moving back, and re-gripping the bar at a predetermined gripping position. The lathe system further includes a gripping position selecting unit capable of selecting a special gripping position at which the spindle re-grips the bar when a state of the machine tool system meets a predetermined condition, the special gripping position being different from the predetermined gripping position.

Abstract: Provided is a lathe capable of elongating the life of a shifter mechanism. A lathe comprises a spindle, a chucking unit, a power transmitting unit, a shifter, a claw, and a driving unit. The shape of an outer circumference of the shifter in a contact range and a first end of the claw in longitudinal section along the spindle axis is such shape as the acceleration “a” of the first end in the diameter direction with respect to the moving distance of the shifter moving in the direction of the spindle axis (Z-axis direction) at a constant speed is continuous both in a positive range and in a negative range where the contact range is a range of the outer circumference of the shifter in contact with the first end of the claw.

Abstract: A machine tool improving measurement accuracy of a machined workpiece diameter. A machine tool comprises a displacement sensor mounted on at least one of a guide bush and a spindle supporting unit. The machine tool further comprises a calculating unit which calculates a diameter of the machined workpiece based on a measurement value of the machined workpiece by the displacement sensor. The spindle is movable back and forth in an axial direction. The spindle is retracted after machining to bring a machined portion of the workpiece to a predetermined measurement position in the axial direction to allow the displacement sensor to measure the machined portion.

Abstract: A lathe capable of shortening a cycle time of workpiece machining. A lathe includes a first spindle, a second spindle opposite the first spindle, a tool post on which a cut-off tool is provided, and a control unit which controls rotation of the first and the second spindles and further controls relative movement of the first and the second spindles and the tool post to cut-off the workpiece. The control unit adds a rotation speed fluctuation to a rotation speed of the first spindle after rotating the first spindle and the second spindle synchronously and detects a rotation speed of the second spindle. The control unit determines that the workpiece is normally cut-off upon determining that a detected fluctuation in the rotation speed of the second spindle is within a predetermined range.

Abstract: A machine tool improving measurement accuracy of a machined workpiece diameter. A machine tool comprises a displacement sensor mounted on at least one of a guide bush and a spindle supporting unit. The machine tool further comprises a calculating unit which calculates a diameter of the machined workpiece based on a measurement value of the machined workpiece by the displacement sensor. The spindle is movable back and forth in an axial direction. The spindle is retracted after machining to bring a machined portion of the workpiece to a predetermined measurement position in the axial direction to allow the displacement sensor to measure the machined portion.

Abstract: Provided is a lathe capable of elongating the life of a shifter mechanism. A lathe comprises a spindle, a chucking unit, a power transmitting unit, a shifter, a claw, and a driving unit. The shape of an outer circumference of the shifter in a contact range and a first end of the claw in longitudinal section along the spindle axis is such shape as the acceleration “a” of the first end in the diameter direction with respect to the moving distance of the shifter moving in the direction of the spindle axis (Z-axis direction) at a constant speed is continuous both in a positive range and in a negative range where the contact range is a range of the outer circumference of the shifter in contact with the first end of the claw.

Abstract: A machine tool capable of reducing the time required to transfer a workpiece includes a spindle chuck provided to a spindle that rotates about an axis, and capable of holding a workpiece to be worked on, a temporary placement chuck capable of holding a workpiece, a tool post driver to move the temporary placement chuck relatively to a facing position in which the spindle-side workpiece holder and the workpiece holder for temporary placement are able to transfer or receive a workpiece to or from each other, and to a separated position in which the spindle-side workpiece holder and the workpiece holder for temporary placement are able to transfer or receive a workpiece individually, and a loader including a spindle-corresponding workpiece holder and a temporary placement-corresponding workpiece holder disposed to face the spindle chuck and the temporary placement chuck in the separated position, respectively.

Abstract: A machine tool capable of reducing the time required to transfer a workpiece includes a spindle chuck provided to a spindle that rotates about an axis, and capable of holding a workpiece to be worked on, a temporary placement chuck capable of holding a workpiece, a tool post driver to move the temporary placement chuck relatively to a facing position in which the spindle-side workpiece holder and the workpiece holder for temporary placement are able to transfer or receive a workpiece to or from each other, and to a separated position in which the spindle-side workpiece holder and the workpiece holder for temporary placement are able to transfer or receive a workpiece individually, and a loader including a spindle-corresponding workpiece holder and a temporary placement-corresponding workpiece holder disposed to face the spindle chuck and the temporary placement chuck in the separated position, respectively.