Multi-function machine tool which permits complex machining of long pieces

A machine tool intended for the machining of parts by the removal of chips, of the machine-tool type comprising:

• a rotary workpiece holder and a toolholder being supported by a common frame;
• said workpiece holder being rotatable around a turning axis, the said turning axis overlying a table having a flat upper face which is parallel to said turning axis and includes means for fastening at least one support means;
• said toolholder being moveable with respect to the workpiece along three orthogonal axes and including two clamping mandrels, one for a stationary tool and the other for a rotary tool;
• said frame including a first workpiece-holder bench and a second toolholder bench, both formed of a material from the group consisting of granite and reconstituted granite, said toolholder bench including a pair of first slideways parallel to said turning axis and arranged in a substantially horizontal plane, the said first slideways serving as a first guide for a first carriage which is moveable horizontally along said first slideways and includes an elongated saddle with a column wherein said column includes a pair of second slideways arranged in a plane perpendicular to the plane of said first slideways and perpendicular to the turning axis, the said second slideways serving as a second guide for a second vertically moveable carriage said second carriage including a pair of third slideways which are arranged in a plane perpendicular to the planes of said first and second slideways and perpendicular to the turning axis, the third slideways serving as a third guide for a horizontally moveable third carriage which supports the toolholder at an end thereof;
• a partition separating a first machining compartment located above the first bench from a second compartment in which centering members are arranged, said partition including in a longitudinal portion thereof a curtain with vertical and horizontal slats surrounding said third carriage, the said slats being mounted for slidable movement relative to each other in order to permit the triaxial movement of said third carriage;
• and
• said workpiece holder being operatively connected to drive means allowing said workpiece holder to perform one of the three kinematics of the following group of kinematics:
• the immobilizing in a given angular position, a slow speed of rotation for milling operations not parallel to the turning axis, and a high speed of rotation for turning operations.