Patent ID: 9541137
Date: 2017-01-10
CPC Classifications: B23Q,F16C

Claim:
1. A bearing device having a plurality of axially juxtaposed rolling bearings, each of the rolling bearings having an inner ring mounted on a main shaft and an outer ring accommodated in a housing; an inner ring spacer interposed between the inner rings of the neighboring rolling bearings and mounted on the main shaft; an outer ring spacer interposed between the outer rings of the neighboring rolling bearings and accommodated in the housing; and a cooling structure, wherein the cooling structure comprises: a nozzle provided in the outer ring spacer and configured to supply a cooling fluid to the rolling bearings by blowing the cooling fluid to an outer peripheral surface of the inner ring spacer, the cooling fluid including at least one of air and oil, wherein the nozzle has a discharge port side that is inclined forwardly with respect to a direction of rotation of the main shaft, the outer peripheral surface of the inner ring spacer is shaped to guide the cooling fluid, discharged from the nozzle, towards the neighboring rolling bearings on both sides, and the outer peripheral surface of the inner ring spacer includes a circumferential groove positioned at a portion where the cooling fluid discharged from the nozzle is blown, and a spiral groove on each side of the circumferential groove having one end connected with the circumferential groove and approaching the neighboring rolling bearings as a circumferential phase is displaced in the direction of rotation of the main shaft.