Long shaft inner surface machining apparatus and method therefor

A long shaft inner surface machining apparatus that cuts an inner surface of a long shaft including a prepared hole penetrating therethrough in an axial direction so as to copy the prepared hole, comprising:

• a long shaft support device that fixes the long shaft so as not to bend, and rotates the long shaft around a shaft center thereof;
• a machining head capable of being inserted into the prepared hole of the long shaft in the axial direction, including a blade for inner surface machining movable in a radial direction, having a function of letting a rotation center of the blade coincide with a shaft axis of the prepared hole, being movable within the prepared hole in the axial direction, and permitting rotation of the long shaft in a state of being inserted in the prepared hole;
• a head support device that is coupled with the machining head from one end of the long shaft through the prepared hole and moves the machining head in the axial direction;
• and
• a blade drive device that is coupled with the machining head from the other end of the long shaft through the prepared hole and moves the blade in the radial direction.

A long shaft inner surface machining apparatus that cuts an inner surface of a long shaft including a prepared hole penetrating therethrough in an axial direction so as to copy the prepared hole, comprising:

• a long shaft support device that fixes the long shaft so as not to bend, and moves the long shaft in the axial direction;
• a machining head capable of being inserted into the prepared hole of the long shaft in the axial direction, including a blade for inner surface machining movable in a radial direction, having a function of letting a rotation center of the blade coincide with a shaft axis of the prepared hole, and permitting axial direction movement of the long shaft in a state of being inserted in the prepared hole;
• a head support device that is coupled with the machining head from one end of the long shaft through the prepared hole and fixes an axial direction position of the machining head;
• and
• a blade drive device that is coupled with the machining head from the other end of the long shaft through the prepared hole and rotary-drives the blade around a shaft axis.

A long shaft inner surface machining apparatus that cuts an inner surface of a long shaft including a prepared hole penetrating therethrough in an axial direction so as to copy the prepared hole, comprising:

• a long shaft support device that fixes the long shaft so as not to bend, moves the long shaft in the axial direction, and rotates the long shaft around a shaft center thereof;
• a machining head capable of being inserted into the prepared hole of the long shaft in the axial direction, including a blade for inner surface machining movable in a radial direction, having a function of letting a rotation center of the blade coincide with a shaft axis of the prepared hole, and permitting axial direction movement and rotation of the long shaft in a state of being inserted in the prepared hole;
• a head support device that is coupled with the machining head from one end of the long shaft through the prepared hole and fixes an axial direction position of the machining head;
• and
• a blade drive device that is coupled with the machining head from the other end of the long shaft through the prepared hole and moves the blade in the radial direction.

A long shaft inner surface machining method that cuts an inner surface of a long shaft including a prepared hole penetrating therethrough in an axial direction so as to copy the prepared hole, comprising the steps of:

• preparing a machining head including a cylindrical main body, a cylindrical sub body supported rotatably around a shaft axis thereof, and a blade for inner surface machining capable of protruding from the sub body, the main body having a diameter insertable into the prepared hole of the long shaft in the axial direction, and the sub body having a diameter insertable into the prepared hole of a minimum diameter of the long shaft in the axial direction;
• after inserting the machining head into the long shaft, radially expanding a diameter of a pair of inner surface chucks positioned with an interval in an axial direction of the main body so as to let a shaft axis of the main body coincide with a shaft axis of the prepared hole and support the main body movably in the axial direction;
• letting the blade for inner surface machining protrude from the sub body;
• moving the main body in the axial direction from outside, while performing inner surface machining so as to copy the prepared hole by rotary-driving the sub body around a shaft axis thereof from outside;
• and
• then reversing the axial direction of the long shaft, and performing inner machining in a similar manner.

A long shaft inner surface machining method that cuts an inner surface of a long shaft including a prepared hole penetrating therethrough in an axial direction so as to copy the prepared hole, comprising the steps of:

• preparing a machining head including a cylindrical head body and a blade for inner surface machining capable of protruding from the head body, the head body including a part formed with a diameter insertable into the prepared hole of the long shaft in the axial direction and a part formed with a diameter insertable into the prepared hole of a minimum diameter of the long shaft in the axial direction;
• after inserting the machining head into the long shaft, radially expanding a diameter of a pair of inner surface chucks positioned with an interval in an axial direction of the head body so as to let a shaft axis of the machining head coincide with a shaft axis of the prepared hole and support the same movably in the axial direction, while permitting rotation of the long shaft with reference to the machining head;
• letting the blade for inner surface machining protrude from the head body;
• moving the machining head in the axial direction from outside, while rotating the long shaft around the shaft axis to perform inner surface machining so as to copy the prepared hole;
• and
• then reversing the axial direction of the long shaft, and performing inner machining in a similar manner.

A long shaft inner surface machining method that cuts an inner surface of a long shaft including a prepared hole penetrating therethrough in an axial direction so as to copy the prepared hole, comprising the steps of:

• preparing a machining head including a cylindrical main body, a cylindrical sub body supported rotatably around a shaft axis thereof, and a blade for inner surface machining capable of protruding from the sub body, the main body having a diameter insertable into the prepared hole of the long shaft in the axial direction, and the sub body having a diameter insertable into the prepared hole of a minimum diameter of the long shaft in the axial direction;
• after inserting the machining head into the long shaft, radially expanding a diameter of a pair of inner surface chucks positioned with an interval in an axial direction of the main body so as to let a shaft axis of the main body coincide with a shaft axis of the prepared hole in a state of permitting axial direction movement of the long shaft;
• letting the blade for inner surface machining protrude from the sub body;
• moving the long shaft in the axial direction, while rotary-driving the sub body around the shaft axis from outside to perform inner surface machining so as to copy the prepared hole;
• and
• then reversing the axial direction of the long shaft, and performing inner machining in a similar manner.

A long shaft inner surface machining method that cuts an inner surface of a long shaft including a prepared hole penetrating therethrough in an axial direction so as to copy the prepared hole, comprising the steps of:

• preparing a machining head including a cylindrical head body and a blade for inner surface machining capable of protruding from the head body, the head body including a part formed with a diameter insertable into the prepared hole of the long shaft in the axial direction and a part formed with a diameter insertable into the prepared hole of the long shaft in the axial direction;
• after inserting the machining head into the long shaft, radially expanding a diameter of a pair of inner surface chucks positioned with an interval in an axial direction of the head body so as to let a shaft axis of the machining head coincide with a shaft axis of the prepared hole and permit axial direction movement and rotation of the long shaft with reference to the machining head;
• letting the blade for inner surface machining protrude from the head body;
• moving the long shaft in the axial direction, while rotating the long shaft around the shaft axis to perform inner surface machining so as to copy the prepared hole;
• and
• then reversing the axial direction of the long shaft, and performing inner machining in a similar manner.