Patent ID: 6413026
Filing Date: 2002-07-02
Classification: B23B,B23Q,Y10T

Abstract:
Tool spindle comprising:(a) a spindle axle having a cylinder chamber arranged therein, the spindle axle is provided with at least one essentially axial first channel and at least one essentially axial second channel; (b) a rotor of an electric motor attached to the spindle axle; (c) a moveable pulling rod axially displaceable in the spindle axle for firmly attaching a tool, the pulling rod is provided with a piston accommodated in the cylinder chamber arranged in the spindle axle and having at least one first axial bore and at least one second axial bore, the at least one first bore opens in the cylinder chamber on one side of the piston and the at least one second bore opens in the cylinder chamber on the other side of the piston; (d) a stationary unit having an end of the pulling rod that is opposite to the tool extending therein, the stationary unit is stationary in relation to the rotation of the pulling rod, the at least one first bore of the pulling rod is put under pressure with fluid via the stationary unit to displace the piston and thereby the pulling rod in one direction to firmly attach the tool, and the at least one second bore is put under pressure with fluid via the stationary unit to displace the piston and thereby the pulling rod in the other direction to detach the tool; and whereby, for cooling the spindle axle and the rotor attached thereto, the first channel, via a restriction, opens into the cylinder chamber on the side of the piston that is put under pressure for displacing the pulling rod in a direction to firmly attach the tool, and the second channel opens into the second bore of the pulling rod for leading the fluid back to a source of fluid via the stationary unit.