| 摘要 |
The main spindle device for a machine tool is provided with: a bearing for rotatably supporting the main spindle; a bearing case for holding the bearing; a housing inside which the bearing case is disposed; and a stiffness-switching device, which supports the bearing case with respect to the housing and is able to switch the stiffness of the bearing case support between multiple levels. When the stiffness-switching device is supporting the bearing case at a low stiffness, the main spindle device is formed so that the bearing case slides with respect to the housing. A friction member is disposed on the area where the bearing case slides with respect to the housing. |
