SPINDLE FOR MACHINE TOOLS

摘要

A machine tool spindle (1) having a through hole capable of housing a collect (30) which grips a tool holder (31) and a draw bar (27) to which the collect (30) is attached, and a tapered inner surface which holds the gool holder; the spindle being made of ceramic as a single cylindrical body. The single cylindrical body having a pair of enlongated holes (2) through which a pin (24) which moves the draw bar (27) in the axial direction of the spindle (1) pentrates. The spindle 91) is preferably made of silicon nitride ceramic, and has a thickness greater thatn about 0.1 times its outer diameter and greater than about 0.02 times its length.