A vertical multiple-spindle machine relating to metal cutting machines. This machine comprises a stationary column on which is installed a rotary worktable mounting hydraulic clamping devices and provided with fluid inlet ducts. The stationary column is provided with passages for feeding fluid medium to he hydraulic clamping devices through said ducts, with the worktable in a fixed position. The column is also provided with a circular groove which is arranged to communicate with the fluid source and is formed so that it has portions curved about the outlets from the passages whereby said groove connects the worktable fluid ducts with the fluid source during the rotation of the worktable. This constructional arrangement makes it possible to materially reduce fluid leakage, thereby providing stability of the required fluid pressure in the clamping devices, improving the accuracy of the machine and decreasing waste of power.
The invention relates to a machining center comprising a pallet changing station in combination with a machining station. The pallet changing station includes a rotating column assembly supporting a platform on which multiple fixtures are supported and moved. A portion of the column assembly defines part of a hydraulic conduit for supplying hydraulic fluid from a fluid source to the fixture for use in clamping parts to the fixture. The integration of a portion of the hydraulic conduit with the rotating column reduces the tendency for the hydraulic conduit to become twisted during rotation of the column or for the various threaded connections of the hydraulic conduit from loosening.