Provided is a thermal displacement correction method using a machine learning method but making it possible to, on a user side, calculate a thermal displacement amount appropriate to a machine tool of the user and correct the thermal displacement. In a machine tool on a target user side, a thermal displacement amount between workpiece and tool corresponding to a temperature at a preset measurement point is calculated based on a parameter defining a relation between the temperature and the thermal displacement amount, and a positioning position for workpiece and tool is corrected in accordance with the calculated thermal displacement amount. On a manufacturer side, operational status information of the machine tool on the target user side is obtained, an operational status identical to the obtained operational status on the target user side is reproduced with a machine tool of a same type as the machine tool on the target user side based on the obtained operational status information, a temperature at a measurement point identical to the measurement point on the machine tool on the target user side and a thermal displacement amount between workpiece and tool are measured during reproduction, and the parameter is calculated by machine learning based on the measured temperature and thermal displacement amount. The parameter in the machine tool on the target user side is updated with the calculated parameter.

A machine tool system is equipped with a machine tool and a controller. The machine tool is equipped with a machine tool body and at least one temperature sensor that acquires temperature data of the machine tool body. The controller is equipped with a storage that stores the temperature data acquired in time-series by the temperature sensor, and an auxiliary power supply that supplies power to the temperature sensor and the storage when the supply of power to the machine tool body is stopped. The controller controls the machine tool by using the temperature data over a predetermined time range stored in the storage, and selects, in response to a charge state of the auxiliary power supply, the temperature data to be used in first control after the supply of power to the machine tool body is resumed.

Provided is a thermal displacement correction method using a machine learning method but making it possible to, on a user side, calculate a thermal displacement amount appropriate to a machine tool of the user and correct the thermal displacement. In a machine tool on a target user side, a thermal displacement amount between workpiece and tool corresponding to a temperature at a preset measurement point is calculated based on a parameter defining a relation between the temperature and the thermal displacement amount, and a positioning position for workpiece and tool is corrected in accordance with the calculated thermal displacement amount. On a manufacturer side, operational status information of the machine tool on the target user side is obtained, an operational status identical to the obtained operational status on the target user side is reproduced with a machine tool of a same type as the machine tool on the target user side based on the obtained operational status information, a temperature at a measurement point identical to the measurement point on the machine tool on the target user side and a thermal displacement amount between workpiece and tool are measured during reproduction, and the parameter is calculated by machine learning based on the measured temperature and thermal displacement amount. The parameter in the machine tool on the target user side is updated with the calculated parameter.

To provide a reference temperature setting device, a reference temperature setting method, and a reference temperature setting program capable of setting an appropriate reference temperature for thermal displacement compensation. A reference temperature setting device comprises: an acquisition unit that acquires measured values from multiple temperature sensors installed on a machine; and a determination unit that determines setting timing for a reference temperature for thermal displacement compensation to coincide with a point in time when the measured values satisfy a predetermined condition.

A machine tool system is equipped with a machine tool and a controller. The machine tool is equipped with a machine tool body and at least one temperature sensor that acquires temperature data of the machine tool body. The controller is equipped with a storage that stores the temperature data acquired in time-series by the temperature sensor, and an auxiliary power supply that supplies power to the temperature sensor and the storage when the supply of power to the machine tool body is stopped. The controller controls the machine tool by using the temperature data over a predetermined time range stored in the storage, and selects, in response to a charge state of the auxiliary power supply, the temperature data to be used in first control after the supply of power to the machine tool body is resumed.

A warm up operation planning device that generates a warm up operation plan for a machine tool comprises: a warm up operation program memory in which at least one warm up operation program is stored; a machining plan input unit that inputs a machining plan for a work in a predetermined period; a warm up operation program selection unit that selects the warm up operation program responsive to the state of the machine tool; a warm up operation duration determination unit that determines a warm up operation duration in response to the work; and a warm up operation planning unit that calculates start time and finish time of warm up operation based on the machining plan. The warm up operation program selection unit selects the warm up operation program responsive to the work from the warm up operation program memory.

To provide a reference temperature setting device, a reference temperature setting method, and a reference temperature setting program capable of setting an appropriate reference temperature for thermal displacement compensation. A reference temperature setting device comprises: an acquisition unit that acquires measured values from multiple temperature sensors installed on a machine; and a determination unit that determines setting timing for a reference temperature for thermal displacement compensation to coincide with a point in time when the measured values satisfy a predetermined condition.

A machine tool includes a workpiece holding unit to hold a workpiece. A tool holding unit holds a tool. At least one of the workpiece holding unit and the tool holding unit is drivingly rotatable or drivingly movable in a predetermined direction to machine the workpiece with the tool. Temperature sensors are attached to members constituting the machine tool. An estimator calculates an environmental temperature system thermal displacement amount due to a heat source outside the machine tool. A correction magnification processor calculates an environmental temperature system thermal displacement correction amount. Another estimator calculates a driving system thermal displacement amount due to a heat source in the machine tool. A thermal displacement correction amount adder obtains and outputs a total thermal displacement correction amount based on which the machine tool performs thermal displacement correction control.

A warm up operation planning device that generates a warm up operation plan for a machine tool comprises: a warm up operation program memory in which at least one warm up operation program is stored; a machining plan input unit that inputs a machining plan for a work in a predetermined period; a warm up operation program selection unit that selects the warm up operation program responsive to the state of the machine tool; a warm up operation duration determination unit that determines a warm up operation duration in response to the work; and a warm up operation planning unit that calculates start time and finish time of warm up operation based on the machining plan. The warm up operation program selection unit selects the warm up operation program responsive to the work from the warm up operation program memory.

A machine tool includes a workpiece holding unit to hold a workpiece. A tool holding unit holds a tool. At least one of the workpiece holding unit and the tool holding unit is drivingly rotatable or drivingly movable in a predetermined direction to machine the workpiece with the tool. Temperature sensors are attached to members constituting the machine tool. An estimator calculates an environmental temperature system thermal displacement amount due to a heat source outside the machine tool. A correction magnification processor calculates an environmental temperature system thermal displacement correction amount. Another estimator calculates a driving system thermal displacement amount due to a heat source in the machine tool. A thermal displacement correction amount adder obtains and outputs a total thermal displacement correction amount based on which the machine tool performs thermal displacement correction control.