A machine tool for machine processing workpieces by using a tool having a pull stud at a proximal end portion thereof. The machine tool includes a tool magazine having a number of tool holders each of which is capable of attaching and detaching the tool, a spindle which holds the tool at the time of machine processing the workpieces, and a controller which determines whether or not the pull stud is appropriate on the basis of detected data of a visual sensor which is provided inside or outside the machine tool, and which captures images of the pull stud of a tool holder of the tool, or detected data of a sensor which is provided inside the tool magazine, and which measures length, electric resistance, or electric capacity of the pull stud.

A numerical controller uses a work lattice region setting unit and a rotation axis work lattice region setting unit to form lattice points for error correction and uses a work-caused translation correction amount setting unit to set a correction amount of a work-caused translation error. A work-caused translation correction amount calculation unit calculates a correction amount at a tool center point position, and a correction section of the numerical controller adds the work-caused translation correction amount to positions of three commanded linear axes for error correction.

A displacement compensation device for a machine tool includes a temperature information acquiring unit, a floor information acquiring unit, a displacement amount computing unit, and a compensating unit. The temperature information acquiring unit acquires temperature information from a temperature sensor. The floor information acquiring unit acquires floor information using a floor state sensor measuring a state of a surface or an inside of a floor on which a machine tool is installed. The displacement amount computing unit calculates an estimated displacement amount of the machine tool with a preset displacement estimation formula using the temperature information acquired by the temperature information acquiring unit and the floor information acquired by the floor information acquiring unit as inputs. The compensating unit compensates an axis command value based on the estimated displacement amount calculated by the displacement amount computing unit.

A calibration method for numerical controlled machine tools (1), which uses a kinematic model to generate a compensation model for the positioning error occurring with the movement of the linear (X, Y, Z) and rotation axes (B, C, A) of a machine tool (1). The calibration method measures the positions of a calibration ball (6) with a measurement sequence which includes the combined movement of the calibration ball (6) around two rotation axes (C, B or C, A), wherein the measurements around a first rotation axis (C) include at least two rotational position movements around a second axis (B or A).

A machine tool for machine processing workpieces by using a tool having a pull stud at a proximal end portion thereof. The machine tool includes a tool magazine having a number of tool holders each of which is capable of attaching and detaching the tool, a spindle which holds the tool at the time of machine processing the workpieces, and a controller which determines whether or not the pull stud is appropriate on the basis of detected data of a visual sensor which is provided inside or outside the machine tool, and which captures images of the pull stud of a tool holder of the tool, or detected data of a sensor which is provided inside the tool magazine, and which measures length, electric resistance, or electric capacity of the pull stud.

A calibration method for numerical controlled machine tools (1), which uses a kinematic model to generate a compensation model for the positioning error occurring with the movement of the linear (X, Y, Z) and rotation axes (B, C, A) of a machine tool (1). The calibration method measures the positions of a calibration ball (6) with a measurement sequence which includes the combined movement of the calibration ball (6) around two rotation axes (C, B or C, A), wherein the measurements around a first rotation axis (C) include at least two rotational position movements around a second axis (B or A).

A displacement compensation device for a machine tool includes a temperature information acquiring unit, a floor information acquiring unit, a displacement amount computing unit, and a compensating unit. The temperature information acquiring unit acquires temperature information from a temperature sensor. The floor information acquiring unit acquires floor information using a floor state sensor measuring a state of a surface or an inside of a floor on which a machine tool is installed. The displacement amount computing unit calculates an estimated displacement amount of the machine tool with a preset displacement estimation formula using the temperature information acquired by the temperature information acquiring unit and the floor information acquired by the floor information acquiring unit as inputs. The compensating unit compensates an axis command value based on the estimated displacement amount calculated by the displacement amount computing unit.