Joint structure and wind power generation device

A wind power generation device comprising:

• a main shaft which rotates by wind power;
• a speed increaser which increases a speed of a rotation of the main shaft, and which outputs the rotation from an output shaft;
• a power generator which comprises an input shaft which rotates with the rotation of the output shaft as an input, and which generates power by a rotation of a rotor which rotates integrally with a rotation of the input shaft;
• a shaft joint which is provided between the output shaft and the input shaft, and which allows a torque to be transmitted between the output shaft and the input shaft;
• and
• a joint structure interposed between the shaft joint and a shaft body which is one of the output shaft and the input shaft, the joint structure including:
• a clutch unit interposed between the shaft joint and a shaft body which is one of the output shaft and the input shaft,
• wherein the clutch unit comprises:
• a shaft coupling portion which rotates integrally with the shaft body;
• a joint coupling portion which rotates integrally with the shaft joint;
• and a one-way clutch provided between the shaft coupling portion and the joint coupling portion,
• wherein the one-way clutch makes a connection integrally rotatably between the shaft coupling portion and the joint coupling portion in a state in which a rotation speed of the output shaft is higher than a rotation speed of the input shaft, and releases the connection between the shaft coupling portion and the joint coupling portion in a state in which the rotation speed of the output shaft is lower than the rotation speed of the input shaft,
• wherein the clutch unit further comprises:
• a support member fixed to a fixed object of the wind power generation device;
• and a rolling bearing which is provided between the support member and the joint coupling portion and which supports the joint coupling portion rotatably with respect to the support member,
• wherein the joint coupling portion comprises:
• a rotational flange portion coupled to the shaft joint;
• and a rotational cylindrical portion which rotates integrally with the rotational flange portion and in which the one-way clutch is provided on an inner periphery side of the rotational cylindrical portion,
• wherein the support member comprises:
• a fixed flange portion coupled to the fixed object;
• and a fixed cylindrical portion which is integral with the fixed flange portion, which is concentric with the rotational cylindrical portion and which is situated radially outside the rotational cylindrical portion,
• wherein the rolling bearing is provided between and contacting an inner peripheral surface of the fixed cylindrical portion and an outer peripheral surface of the rotational cylindrical portion, and
• wherein the generator and the speed increaser are on opposite sides of the one-way clutch in an axial direction of the input shaft and the output shaft.