Patent ID: 7547168

Claim:
A high speed spindle assembly for rotating a tool at high rotational rates, comprising: a hollow spindle housing; a spindle shaft configured for rotation within the spindle housing and having a front end and a rear end, the spindle shaft including a front hollow region and a rear hollow region; a motor configured to impart rotational drive forces to the spindle shaft during operation; the spindle shaft including a thrust bearing flange disposed intermediate the front end and the rear end of the spindle shaft and protruding from a peripheral surface of the shaft; a front air bearing and a rear air bearing configured to radially support the spindle shaft for high speed rotational movement; a thrust air bearing disposed between the front air bearing and the rear air bearing within the spindle housing and configured to act on the thrust bearing flange of the spindle shaft to constrain axial movement of the spindle shaft within the spindle housing, wherein the thrust bearing includes a rear thrust bearing structure to the rear of the thrust bearing flange, which rear thrust bearing structure is fastened to the front air bearing such that the front air bearing, the spindle shaft, and the thrust bearing are able to be inserted together into the hollow spindle housing; a collet disposed within the front hollow region of the spindle shaft.