ROTATING SHAFT DEVICE AND MACHINE TOOL HAVING THE ROTATING SHAFT DEVICE

摘要

The invention relates to a rotating shaft apparatus for rotationally driving a spindle or a feed screw shaft and a machine tool including the rotating shaft apparatus, and is directed to enhance durability of a rotating shaft apparatus if the rotating shaft such as a spindle or a feed shaft rotates at a high speed. In order to solve the problem, according to the invention, a rotating shaft is rotationally supported by a bearing to a housing, the bearing being previously applied to or filled with a lubricant. A lubricant impregnated member, which is impregnated with a lubricant to be supplied to the bearing, is provided in the rotating shaft. The lubricant is separated and discharged from the lubricant impregnated member by centrifugal force due to the rotation of the shaft. The lubricant is supplied to the bearing through a lubricant supplying passage which is provided for fluidly connecting a space in or adjacent the bearing to the lubricant impregnated member.