BEARING DEVICE FOR MACHINE TOOL MAIN SPINDLE

摘要

A bearing device for a machine tool main spindle, having an angular contact ball bearing loosely fitted in a housing, in which, with the amount of the looseness maintained, heat of the bearing is released to the housing to suppress a rise in temperature and heat expansion of the bearing. Heat conductive grease (3) containing inorganic powder as a heat conductive material is placed between the bore surface of the housing (12) and each outer ring (2a) of the combination angular contact ball bearing (2) loosely fitted in the housing (12). Heat of the bearing (2) is released from each outer ring (2a) to the housing (12) through the heat conductive grease (3). By this, a rise in temperature and heat expansion of the bearing (2) is suppressed with the amount of looseness of fitting of the bearing in the housing (12) maintained.