Patent ID: 7393165
Filing Date: 2008-07-01
Classification: B23B,Y10T

Abstract:
1. Clamping device for clamping a tool ( 8 ), or tool holder in the front of a working spindle ( 4 ), comprising a drawbar ( 10 ) arranged to be displaced within the working spindle ( 4 ) along an axis, a clamping set ( 12 ) arranged in the working spindle ( 4 ) and displaceable between a clamping position and a released position by means of the drawbar ( 10 ), a spring arrangement ( 14 ) provided for the drawbar ( 10 ) to generate the drawing force for the clamping set ( 12 ) and a releasing unit ( 17 ) by means of which the clamping set ( 12 ) may be moved into the released position by the drawbar ( 10 ) against the force of the spring arrangement ( 14 ), characterized in that the releasing unit ( 17 ) may be operated by an electrical actuator ( 5 , 6 , 33 , 34 ) including a motor ( 5 , 6 ) for rotating the spindle ( 4 ) and a linear motion unit ( 33 , 34 ), and in that the releasing unit ( 17 ) comprises an engageable coupling ( 23 , 24 , 26 , 27 , 28 ) including at least one part that is movable in the axial direction via a coil ( 24 ) and an armature ( 26 ) of the coupling, by means of which axial movement the working spindle ( 4 ) can be connected to the linear motion unit ( 33 , 34 ).