Patent ID: 8443941

Claim:
A cooling/lubricating device for a machine tool feed shaft, comprising: a hollow feed shaft ( 1 ) on the outer circumference of which is formed a screw mating with a nut secured to a slide of the machine tool so as to feed the slide and which is rotatably supported at an end of the feed shaft; a bearing ( 8 ) which rotatably supports the end of the feed shaft ( 1 ); a support member ( 2 ), provided at the end of the feed shaft ( 1 ), for supporting the feed shaft ( 1 ) to be relatively rotated via the bearing ( 8 ); a tube ( 16 ) which is disposed along the axis inside the hollow feed shaft ( 1 ) and which allows cooling lubricant to pass through pathway spaces formed inside the tube ( 16 ) and outside the tube ( 16 ); a first cover member ( 9 ) which contours a feed space ( 12 ) holding the cooling lubricant fed into circumference of the feed shaft ( 1 ) at one side of the support member ( 2 ); and a second cover member ( 10 ) which contours a discharge space ( 13 ) holding the cooling lubricant to be discharged from circumference of the shaft ( 1 ) at the other side of the support member ( 2 ), a channel ( 27 a ) for the cooling lubricant as lubricant flowing outside of the feed shaft ( 1 ) from the feed space ( 12 ) through the bearing ( 8 ) to the discharge space ( 13 ); and a channel ( 20 , 19 ) for the cooling lubricant as refrigerant flowing within the feed shaft ( 1 ) from the feed space ( 12 ) to the discharge space ( 13 ), wherein one part of the cooling lubricant held in the feed space ( 12 ) is allowed to flow as lubricant in the axial direction of the bearing ( 8 ) outside of the feed shaft ( 1 ) and held in the discharge space ( 13 ), and wherein the other part of the cooling lubricant held in the feed space ( 12 ) is allowed to be circulated as refrigerant through the pathway spaces within the feed shaft ( 1 ) and held in the discharge space ( 13 ), so that the cooling lubricant as lubricant and the cooling lubricant as refrigerant flow through separate channels in a parallel manner respectively.