Tool head with spindle bearing arrangement

The invention relates to a tool head with a spindle bearing arrangement The bearings (9, 10) of said arrangement rest with one of their bearing shells on a driven spindle (2) with a tool holding fixture (1). With their other bearing shell they interact with a housing (8) in such a manner that in at least one part (10) of the bearings (9, 10) the respective other bearing shell interacts with a sliding piece (11) which is slideable along the housing (8) in the one sliding direction and which locks the spindle (2) with the housing (8) in a locking position. In the other sliding direction, said sliding piece releases the spindle in a release position. The invention provides a universally useful tool head by the following configuration: The respective other bearing shell of the one part (10) of the bearings (9, 10) is at least partially enclosed by the sliding piece (11). Said sliding piece (11) is forced into the locking position with a predetermined contact force by a drive device. The sliding piece closely fits the housing (8) when the lock is released. Said tool head can be used for both milling and turning on a lathe. The tool head provides also a means for simultaneously relieving the spindle bearing arrangement when the tool is operated in a nonrotative mode.