COLLET CHUCK DEVICE AND MACHINE TOOL INCLUDING THE SAME

PROBLEM TO BE SOLVED: To provide a collet chuck device which handles a workpiece having a large diameter that an existing machine tool cannot handle.SOLUTION: A collet chuck device includes: a cylindrical holder 20 which has a tip extension part 21 further protruding in an axial direction C than a tip part 81 of a spindle 80 and is fixed to the spindle 80; a sleeve 30 including a body part 31 inserted into the spindle 80 and a collet pressing part 32 further protruding in the axial direction C than the tip part 81 of the spindle 80; a collet chuck 40 inserted into the sleeve 30 and having a holding part 42 further protruding in the axial direction C than the tip part 81 of the spindle 80; and a pin 50 which penetrates through the tip extension part 21 of the holder 20, the sleeve 30, and the collet chuck 40 in a radial direction D of the spindle 80 and restricts the collet chuck 40 from moving in the axial direction C.