Patent ID: 8967864
Filing Date: 2015-03-03
Classification: B23Q,F16C

Abstract:
1. A main spindle device of a machine tool, comprising: a plurality of bearings that rotatably support a main spindle of the machine tool, and that are placed inside a housing with a pressure receiving member interposed between the bearings and the housing, wherein the pressure receiving member has a first cylindrical portion and a second cylindrical portion in an axial direction, the first cylindrical portion being connected with the second cylindrical portion, the second cylindrical portion being thicker than the first cylindrical portion, the pressure receiving member is capable of moving in a direction perpendicular to an axial direction of the main spindle, a pressure chamber, which a pressure medium pressing the pressure receiving member toward the bearings in the perpendicular direction is supplied to, is formed in the housing, so that the pressure receiving member is arranged to contact to the plurality of bearings, and a plurality of the pressure chambers are independently formed in the housing so as to correspond to the bearings, respectively, the main spindle device of the machine tool further comprising: a plurality of adjustment units provided independently so as to correspond the pressure chambers, respectively, and each capable of independently adjusting a pressure of the pressure medium for a corresponding one of the pressure chambers.