Machine tool, control method, and control program

A control method for a machine tool,

• the machine tool including:
• a workpiece spindle configured to hold a workpiece;
• a tool holding portion configured to hold a pinion cutter;
• a first rotation drive unit configured to drive the workpiece spindle to rotate about a first axis extending along an axial direction of the workpiece spindle;
• a feed drive unit configured to move the tool holding portion;
• a second rotation drive unit configured to drive the tool holding portion to rotate about a second axis extending along an axial direction of the pinion cutter;
• a first brake mechanism configured to brake rotation of the workpiece spindle;
• a second brake mechanism configured to brake rotation of the tool holding portion;
• and
• a control unit configured to control the feed drive unit, the first and second rotation drive units, and the first and second brake mechanisms,
• the control method comprising causing the control unit to execute:
• a reciprocating driving step of driving the tool holding portion to reciprocate along the first axis to perform gear cutting on an inner peripheral surface of the workpiece or an outer peripheral surface of the workpiece;
• and
• an adjusting step of adjusting a rotation angle between the workpiece spindle and the tool holding portion by rotating the workpiece spindle by a predetermined angle about the first axis and rotating the tool holding portion by a predetermined angle about the second axis,
• wherein the reciprocating driving step is executed while braking by the first brake mechanism and braking by the second brake mechanism are applied, and
• the adjusting step is executed while neither braking by the first brake mechanism nor braking by the second brake mechanism is applied.

A non-transitory recording medium storing a control program for a machine tool,

• the machine tool including:
• a workpiece spindle configured to be able to hold a workpiece;
• a tool holding portion configured to hold a pinion cutter;
• a first rotation drive unit configured to drive the workpiece spindle to rotate about a first axis extending along an axial direction of the workpiece spindle;
• a feed drive unit configured to move the tool holding portion;
• a second rotation drive unit configured to drive the tool holding portion to rotate about a second axis extending along an axial direction of the pinion cutter;
• a first brake mechanism configured to brake rotation of the workpiece spindle;
• a second brake mechanism configured to brake rotation of the tool holding portion;
• and
• a control unit configured to control the feed drive unit, the first and second rotation drive units, and the first and second brake mechanisms,
• the control program causing the control unit to execute:
• reciprocating drive processing for performing gear cutting on an inner peripheral surface or an outer peripheral surface of the workpiece by driving the tool holding portion to reciprocate along the first axis, and
• adjustment processing for adjusting a rotation angle between the workpiece spindle and the tool holding portion by rotating the workpiece spindle by a predetermined angle about the first axis and rotating the tool holding portion by a predetermined angle about the second axis,
• wherein the reciprocating drive processing is executed while braking by the first brake mechanism and braking by the second brake mechanism are applied, and
• the adjustment processing is executed while neither braking by the first brake mechanism nor braking by the second brake mechanism is applied.