Machine tools

A machining assembly which operates by sequences of multiple operations with the aid of a plurality of machining heads equipped with at least one working spindle and a single machining unit, including in combination

• means for rotating the spindles and means for feeding the heads in approach and return motions with respect to the successive parts to be machined,
• cross-transfer means for ensuring simultaneously the positioning at a central position on the machining unit of a head and the discharge of the preceding head said cross-transfer means having a feed end section and a discharge end section, and
• means for circulating the heads forward and interconnecting the two end sections of the cross transfer so as to recirculate the heads,
• the feed and discharge end sections of the cross transfer being tiltable about a horizontal axis from a vertical position to a horizontal position in such a way that the heads are used with their spindles horizontal but are moved on the circulating means with their spindles vertical,
• each said end section ensuring in its vertical position the direct cross transfer of the heads without intermediate movement from or towards the machining unit, and in its horizontal position the horizontal transfer of the heads in the direction perpendicular to the axis of tilt,
• wherein each head is integral with a baseplate which is vertical in the working position and includes a bottom edge and two parts located at the ends of the said edge and extending forwards and downwards from said bottom edge, each of these parts including a plate having a notch at the bottom, these two notches lying at a certain pitch nearly the length of the baseplate,
• the said notched plate cooperating with two vertical catches the top ends of which are at a level lower than that of the said bottom edge, each of these catches being integral with a carriage mounted on said assembly for guidance in the transverse direction, which carriage is integral with the end of one of the rods of a double-rod jack the stroke of which corresponds with the length of the transfer, being slightly greater than said length of the baseplate,
• the two catches thus made integral with one another being located at a distance apart exactly equal to said pitch plus said stroke and positioned for cooperating with said notched plates to achieve engagement and release therebetween, the mutual engagement and release of the catches and notched plates being achieved exclusively in the central position on the machining unit by the return and approach motions of the machining unit and in the end positions by the motions of raising into the vertical position and of tilting into the horizontal position of said feed and discharge end sections of the cross transfer.