Rotating shaft

A rotating shaft equipped with a hollow tubular shaped outer shaft, and an inner shaft that is removably inserted into a hollow interior of the outer shaft, wherein:

• the outer shaft includes a first hollow end part, which is one end part in an axial direction of the rotating shaft, and a second hollow end part, which is another end part in the axial direction;
• the inner shaft includes a first end part, which is one end part in the axial direction, and a second end part, which is another end part in the axial direction;
• the first end part includes an extending portion configured to be exposed from the first hollow end part and to extend along the axial direction and along a direction to separate away from the first hollow end part;
• the rotating shaft comprises a positioning and fixing member configured to position and fix the extending portion with respect to the first hollow end part;
• the positioning and fixing member comprises:
• a nut member configured to be screw-engaged with an outer circumferential surface of the extending portion;
• a locking sleeve surrounding the nut member;
• and
• a locking ring configured to engage with the nut member and the extending portion;
• the nut member includes a contact surface configured to contact an end surface of the first hollow end part in the axial direction;
• the locking sleeve comprises:
• a first engaging member configured to engage with a first locking member provided on the first hollow end part, and to restrict relative rotation between the locking sleeve and the first hollow end part about an axial line of the rotating shaft;
• a second engaging member configured to engage with a second locking member provided on the nut member, and to restrict relative rotation between the locking sleeve and the nut member about the axial line;
• and
• the locking ring comprises:
• a third engaging member configured to engage with a third locking member provided on the nut member, and to restrict relative rotation between the nut member and the locking ring about the axial line;
• and
• a fourth engaging member configured to engage with a fourth locking member provided on the extending portion, and to restrict relative rotation between the locking ring and the extending portion about the axial line.