Spindle unit having pressure foot

摘要

A spindle unit having a pressure foot whose machining efficiency may be improved even when compressed air is used as means for pressing the pressure foot. The spindle unit having the pressure foot includes a rotor shaft provided within a base rotatably and movably along an axis, a collet chuck provided at one end of the rotor shaft, a linear motor for moving a movable element rotatably connected with the rotor shaft and movably provided within the base along the axis together with the rotor shaft to move a drill closer to or apart from the workpiece, a rotary motor for rotating the rotor shaft, a pressure foot disposed in front of the edge of the collet chuck and is capable of pressing down the workpiece, and air cylinders for connecting the movable element with the pressure foot so as to be relatively movable by a predetermined degree and for pressing the pressure foot in the direction separating from the collet chuck.