An eyeglass lens processing apparatus for processing a periphery of an eyeglass lens includes: a lens chuck shaft configured to chuck the eyeglass lens; a shaft angle changing portion configured to change a shaft angle of the lens chuck shaft; a first processing tool unit including at least one spindle at which a first processing tool is provided; a second processing tool unit that is disposed to oppose the first processing tool unit and that includes at least one spindle at which a second processing tool is provided; and a controller configured to change one of the first and second processing tool unit to be used for processing the eyeglass lens to the other of the first and second processing tool by controlling driving of the shaft angle changing portion to change the shaft angle of the lens chuck shaft.

The invention relates to a machine tool as well as to a method for operating the machine tool. The machine tool comprises a workpiece carrier (20) that can be incrementally rotated about an incremental advance axis (22) and has several carrier sides (25). A first workpiece chuck unit (26) for holding a workpiece in a first position (P1) and a second workpiece chuck unit (27) for holding a workpiece in a second position (P2) are arranged on each carrier side (25). In each angular position or incremental advance position of the workpiece carrier (20), one carrier side (25) is in a loading station (30), one carrier side (25) is in an unloading station 31, and the respectively other carrier sides (25) are in respectively one work station (32). A workpiece changing device (34) is provided, said device moving a partially machined workpiece (16a) out of the first position (P1) in the unloading station (31) into the second position (P2) in the loading station. The position change of the partially machined workpiece (16a) preferably also takes place during the incremental advance movement of the workpiece carrier (20). Preferably, the partially machined workpiece (16a) can be turned in doing so.