Abstract: A balancing device of a unit formed by a first machine carriage (1) supporting a second mobile carriage (4) on the first, in any direction other than the vertical, by means of a counterweight (6) connected to the first carriage (1) via chains (7, 8). This transmission comprises at least two chains (7 and 8) connected to said first carriage (1) via return-pulleys (13, 14) entrained by said chains (7 and 8) and acting on a torsion shaft (15), the relative length of the chain sections (7a, 8a) connecting the pulleys (13, 14) to said first carriage (1) being variable as a function of the displacement of the second carriage (4).

Abstract: An improved tool exchange apparatus for milling machines with sliding carriages comprising a magazine and a pincer-arm for conveyance.The magazine is disposed so that the tools are presented with horizontal axis at an exchange station, the pincer-arm is rotatably mounted on one of the horizontal axes of a crank having two parallel horizontal axes. The crank itself is rotatably and slidably mounted along the other horizontal axis to a rotary head which is rotatable about a vertical axis which is fixed relative to the magazine.

Abstract: Machine tools with a horizontally sliding tool-holding ram in which a force is applied to the anterior end of the ram by a bar which moves with the ram, running on a first roller located on the front of the ram support, and under a second roller located on the rear of the ram support, the different pairs of rollers and the associate bar or bars being disposed and shaped in such a way as to apply, to the anterior part of the ram, an upwardly directed force for balancing the weight of the ram and of the tooling which it carries.