Gear machining device and gear machining method

A gear machining device for machining tooth bottoms and first and second side surfaces of teeth of a gear by using a machining tool which has a rotation axis inclined relative to a rotation axis of a workpiece and feeding the machining tool relatively in a rotation axis direction of the workpiece by rotating the machining tool in synchronization with a rotation of the workpiece, wherein a profile of a tool end surface of the machining tool before grinding of blades of the machining tool is different from the profile of the tool end surface of the machining tool after grinding thereof, the gear machining device comprising:

• a tool state memorizing portion for memorizing tool states each including a position or a posture of the machining tool relative to the workpiece and obtained based on profiles of the tool end surface of the machining tool before and after the grinding;
• and
• a machining control portion which controls machining of the tooth bottoms, the first side surfaces and the second side surfaces before grinding the blades of the machining tool, under respective tool states of the machining tool before the grinding memorized in the tool state memorizing portion and controls machining of the tooth bottoms, the first side surfaces and the second side surfaces after grinding the blades of the machining tool, under the tool states of the machining tool after the grinding memorized in the tool state memorizing portion.

A gear machining method for machining tooth bottoms and first and second side surfaces of teeth of a gear by using a machining tool which has a rotation axis inclined relative to a rotation axis of a workpiece and feeding the machining tool relatively in a rotation axis direction of the workpiece by rotating the machining tool in synchronization with a rotation of the workpiece, the gear machining method comprising the processes of:

• a tooth bottom tool state calculating process for calculating a tooth bottom tool state including a position or a posture of the machining tool relative to the workpiece for machining the tooth bottom between adjacent teeth of the gear;
• a first side surface tool state calculating process for calculating a first side surface tool state including a position or a posture of the machining tool relative to the workpiece for machining the first side surface of one of the adjacent teeth facing the tooth bottom;
• a second side surface tool state calculating process for calculating a second side surface tool state including a position or a posture of the machining tool relative to the workpiece for machining the second side surface of the other of the adjacent teeth facing the tooth bottom;
• and
• a machining controlling process for controlling machining of the tooth bottoms, the first side surfaces and the second side surfaces under the respective tool states of the machining tool calculated in the tooth bottom tool state calculating process, the first side surface tool state calculating process and the second side surface tool state calculating process, respectively.

A gear machining method for machining tooth bottoms and first and second surfaces of teeth of a gear by using a machining tool which has a rotation axis inclined relative to a rotation axis of a workpiece and feeding the machining tool relatively in a rotation axis direction of the workpiece by rotating the machining tool in synchronization with a rotation of the workpiece, wherein a profile of a tool end surface of the machining tool before grinding of blades of the machining tool is different from a profile of the tool end surface of the machining tool after grinding thereof, the gear machining method comprising the processes of:

• a tooth bottom tool state calculating process for calculating a tooth bottom tool state including a position or a posture of the machining tool relative to the workpiece for machining the tooth bottom between adjacent teeth of the gear based on the respective profiles of the tool end surface of the machining tool before and after the grinding;
• a first side surface tool state calculating process for calculating a first side surface tool state including a position or a posture of the machining tool relative to the workpiece for machining the first side surface of one of the adjacent teeth facing the tooth bottom based on the respective profiles of the tool end surface of the machining tool before and after the grinding;
• a second side surface tool state calculating process for calculating a second side surface tool state including a position or a posture of the machining tool relative to the workpiece for machining the second side surface of the other of the adjacent teeth facing the tooth bottom based on the respective profiles of the tool end surface of the machining tool before and after the grinding;
• and
• a machining controlling process for controlling machining of the tooth bottoms, the first side surfaces and the second side surfaces before grinding the blades of the machining tool, under the respective tool states of the machining tool calculated based on the profile of the tool end surface of the machining tool before the grinding in the tooth bottom tool state calculating process, the first side surface tool state calculating process and the second side surface tool state calculating process, and for controlling machining of the tooth bottoms, the first side surfaces and the second side surfaces after grinding the blades of the machining tool, under the respective tool states of the machining tool calculated based on the profile of the tool end surface of the machining tool after the grinding in the tooth bottom tool state calculating process, the first side surface tool state calculating process and the second side surface tool state calculating process.