ROTARY DEVICE

PROBLEM TO BE SOLVED: To provide a rotary device that can evacuate heat generated by the rotary device, which increases as the rotary device grows in speed and capacity, to outside appropriately.SOLUTION: A coupling 5 is connected to an end of a shaft 41 of a dynamo and also to an end of an output shaft 101 of an engine. In the coupling 5, a flow channel 515 communicating with a through-hole 41a provided in the shaft 41 is formed radially. Rotation of the shaft 41 generates centrifugal force in the air in the channel 515 of the coupling 5 to evacuate the air to outside, which generates a negative pressure in the channel 515. By this generation of the negative pressure, the air flows into the through-hole 41a of the shaft 41 from the other end of the shaft 41 and flows into a concavity 511 and the flow channel 515 of the coupling 5 via the through-hole 41a. This can effectively cool a rotor core, the shaft 41, and a bearing.