Patent ID: 7674217
Filing Date: 2010-03-09
Classification: B23Q,Y10S,Y10T

Abstract:
1. A machine tool with a spindle chuck replacing mechanism characterized by comprising: a spindle having a chuck coupling portion at a tip thereof and rotationally driven by a spindle motor; a plurality of spindle chucks each capable of holding a work, the spindle chucks being selectively engageable with the chuck coupling portion of the spindle so as to be disengageable from the chuck coupling portion; a spindle chuck replacing mechanism rotatably supporting the plurality of spindle chucks and freely transferring any one of the spindle chucks between a processing position where the one spindle chuck is positioned in front of the spindle and a work replacement position where the work on the one spindle chuck is replaced with a new one, the spindle chuck replacing mechanism coupling and decoupling the one spindle chuck in the processing position to and from the chuck coupling portion of the spindle; and a pre-rotation-transmission mechanism transmitting rotation of the spindle motor, via a path different from a driving path between the chuck coupling portion of the spindle and the spindle motor, to the one spindle chuck when the one spindle chuck is located in the processing position and not coupled to the chuck coupling portion of the spindle, and in that the pre-rotation-transmission mechanism makes a difference in rotation speed between the one spindle chuck located in the processing position and not coupled to the chuck coupling portion of the spindle and the spindle and has a speed difference absorbing mechanism absorbing the difference in rotation speed with the one spindle chuck when the one spindle chuck is coupled to the chuck coupling portion of the spindle.