| 摘要 |
PURPOSE:To effectively cool a shaft or bearing by providing a cooling oil passage in the shaft along its axial direction and a oil reservoir at one end of the passage. CONSTITUTION:A cooling oil passage 13 is provided in a shaft 2 along its axial direction and an oil reservoir 18 is formed immediately below a motor 30 on the lower end side of the shaft 2. Since the shaft 2 and a rotor 3 are cooled with oil by making a large amount of cooling oil to flow through the shaft 2 in such a way, rolling bearings 5 and 6 are also cooled effectively. Therefore, the breakdown of the bearings 5 and 6 due to high temperatures can be prevented and the service lives of the bearings 5 and 6 can be prolonged. |
