A machine tool configured to attach multiple tools to a turret is provided to improve the efficiency of a tool exchanging operation and, thus, also the production efficiency. A control device determines whether an expired tool, which is a tool needs to be exchanged, is present among the tools held by the turret. The control device sets a tool exchanging position, which is a position within the movable range of a head section and is a position where the expired tool is exchanged with a new tool. If the control device determines that an expired tool is present, the control device causes a head section driving device to move the head and rotate the turret to position the expired tool at the tool exchanging position.

A cutting tool, a turning machine including the cutting tool, and an associated method are provided. The cutting tool includes a tool, a cutting head, a strain gauge, and an accelerometer. The cutting head is located at the tool bar and has a cutting edge. The strain gauge measures strain at the tool bar. The accelerometer measures acceleration at the tool bar or the cutting head. Deflection of the cutting edge is estimated based on output from the strain gauge and the accelerometer. In some embodiments, the accelerometer is arranged close to the cutting edge, while the strain gauge is arranged where the tool bar is susceptible to the largest strain. In some embodiments, low frequency vibrations of the cutting edge are estimated based on measured strain, high frequency vibrations are estimated based on measured acceleration, and medium frequency vibrations are estimated based on output from both sensor types.

In a method for determining the state of wear of a tool, at least one optical image of a surface of the tool is recorded. Image data of the at least one optical image are processed in order to detect a wear zone. A surface extent and/or spatial extent of the wear zone is determined. The state of wear of the tool is classified on the basis of the extent determined. An apparatus for determining the state of wear of a tool correspondingly comprises a camera for recording at least one optical image of a surface of the tool, an image processing module which is configured in such a way that it processes image data of the at least one optical image in order to detect a wear zone, a computation module which is configured in such a way that it determines a surface extent and/or spatial extent of the wear zone, and a classifier module which is configured in such a way that it classifies the state of wear of the tool on the basis of the extent determined.

A machine tool with a spindle stock 20 and a tool rest 40 mounted on a bed 11, in which the spindle stock 20 and the tool rest 40 are able to relatively move in an X-axis direction that is a diameter direction of a spindle and a Z-axis direction that is an axial direction of the spindle, includes: a linear scale 50 disposed over the spindle stock 20 and the tool rest 40 on an upper side in the X-axis direction to detect position information in the X-axis direction; and a rail 23 extending in the Z-axis direction, and the linear scale 50 moves in the Z-axis direction while guided by the rail 23 integrally with either the spindle stock 20 or the tool rest 40 when the spindle stock 20 and the tool rest 40 relatively move in the Z-axis direction.

A machine tool includes: a spindle unit for rotatably supporting a spindle; a moving mechanism for moving the spindle unit; a motor for driving the moving mechanism; a motor control unit for controlling the motor; and an estimation unit for estimating that abnormal vibration is likely to have occurred in the spindle when the amplitude of a signal indicating the driving state of the motor falls out of a predetermined allowable range.

An estimating device estimating a rotary axis position of a workpiece includes first and second position acquisition units acquiring tool positions in first and second directions, a load acquisition unit acquiring first and second directional loads of the tool in the first and second directions, a determination unit determining whether or not the first and second directional loads each are a threshold or less, a turning control unit performing a lathe turning on the workpiece until the first directional load becomes the threshold or less and thereafter performing a lathe turning thereon until the second directional load becomes the threshold or less, and an estimating unit estimating the rotary axis position based on a first directional position of the tool when the first directional load has become the threshold or less, and a second directional position thereof when the second directional load has become the threshold or less.

A numerical control device according to an aspect of the present disclosure includes: a reference speed calculation unit configured to calculate a spindle speed which is a rotation number of the spindle in accordance with a machining program, and a feed speed which is a movement speed of the feed axis in accordance with the machining program; an oscillation command calculation unit configured to calculate an oscillation command, which is a periodic variation component superimposed on a command of the feed axis, based on the spindle speed and the feed speed, as well as an oscillation frequency magnification set in advance; a setting acquisition unit configured to acquire an upper limit value for frequency of the oscillation command; and an adjustment unit configured to adjust the frequency of the oscillation command, or adjust at least either of the spindle speed and the oscillation frequency magnification, so that the frequency of the oscillation command does not exceed the upper limit value.

A machine tool configured to attach multiple tools to a turret is provided to improve the efficiency of a tool exchanging operation and, thus, also the production efficiency. A control device determines whether an expired tool, which is a tool needs to be exchanged, is present among the tools held by the turret. The control device sets a tool exchanging position, which is a position within the movable range of a head section and is a position where the expired tool is exchanged with a new tool. If the control device determines that an expired tool is present, the control device causes a head section driving device to move the head and rotate the turret to position the expired tool at the tool exchanging position.

A cutting tool, a turning machine including the cutting tool, and an associated method are provided. The cutting tool includes a tool bar extending along an axis, a cutting head located at the tool bar, and at least one sensor integrated with the tool bar or the cutting head. A rotational orientation of the cutting tool with respect to the axis is estimated based on output provided by the at least one sensor. In at least some embodiments, the at least one sensor includes accelerometers configured to measure acceleration in at least two directions.

A numerical control apparatus that is a selection apparatus causes, when an automatic lathe that fabricates a workpiece from a bar is unable to fabricate a workpiece that is a fabrication target from a remaining material that is a remaining part of the bar being machined, the automatic lathe to select another workpiece that the automatic lathe is able to fabricate from the remaining material. The numerical control apparatus includes a selection unit to select, when there are a plurality of other workpieces that are able to be fabricated from the remaining material, a workpiece to be fabricated on the basis of a length of the remaining material and priority.