Patent ID: 8881352

Claim:
A machining device for machining crankshafts, the machining device comprising: a housing; a tool for machining crankshafts having crankshaft walls and cylindrical bearing surfaces, the tool comprising a disk-shaped base body with blade inserts arranged on the outer periphery of the disk-shaped base body; a first drive unit arranged on the housing for rotationally driving the tool about an axis of rotation; a first supply line for a cryogenic cooling medium arranged concentrically with the axis of rotation of the tool, wherein the first supply line is thermally insulated in at least some sections; a plurality of second supply lines on the tool which receive cryogenic cooling medium from the first supply line, wherein the second supply lines are radially arranged relative to the axis of rotation and lead to the blade inserts on the periphery of the base body, wherein the second supply lines are thermally insulated in at least some sections; a rotary distributor unit connecting the first supply line to less than all of the second supply lines and supplying the cryogenic cooling medium through the second supply lines to less than all of the blade inserts, wherein the rotary distributor unit is arranged concentrically with the axis of rotation of the tool; the rotary distributor unit comprising a first distributor part and a second distributor part, the first distributor part being cylindrical and having a first borehole that is axially aligned with the axis of rotation of the disk-shaped tool and the second distributor part being ring shaped and surrounding a section of the first distributor part; a plurality of second boreholes formed in the first distributor part and arranged radially relative to the axis of rotation of the disk-shaped tool, the second boreholes being in communication with the first borehole; an outer circumferential surface on the first supply line; and, a directional outlet opening formed on the outer circumferential surface of the first supply line, the first supply line being positioned in the first borehole, whereby the directional outlet opening may be directed toward selected ones of the second boreholes and the point of the engagement of the tool with the crankshaft, and whereby the rotary distributor unit causes the cooling medium to flow to the blade inserts that are engaged with the crankshaft and blocks the cooling medium from flowing to the blade inserts that are not engaged with the crankshaft.