ACTUATING DEVICE FOR A TOOL OR WORKPIECE TENSIONING JACK IN A MACHINE TOOL SPINDLE

摘要

The invention relates to an actuating device for a tool or a workpiece tensioning jack in a machine tool spindle, comprising a pressure piston (10) which is arranged inside a housing (5, 6) for actuating the tool or workpiece tensioning jack (2). In order to provide a compact, space-saving actuating device enabling leakage fluid to be drained off in a simple manner, several interspaced continuous bores (16) are arranged concentrically around a centre axis (15) in a side wall (17) of the housing (5,6), pressure plungers(14) which are axially displaceable with the aid of the pressure piston are disposed therein and the housing contains at least one leakage channel (22) with a section (25) extending between the pressure plungers (14) in a radially outer direction.