Abstract: A machine having a plurality of workpiece spindles. The spindles are angularly disposed in an indexable support with the spindle axes making one and the same axis with the axis of the support and all being tangent to a common cylinder coaxial with the support axis. Means are provided for driving the spindles and chucks are mounted on one end of the spindles for carrying workpieces for cooperation with tools mounted in the frame in which the support is indexable.

Abstract: A machine tool having a turret head equipped with a plurality of multiple spindle units on the support stations thereof with the exception of one station rotatably supporting a tool spindle adapted to removably receive a tool, a tool storage magazine storing a plurality of "single" tools, and tool changing apparatus for interchanging the tools between the tool spindle and the tool storage magazine. The turret head may be rotated to successively position one of the multiple spindle units or the tool spindle at an operating position that confronts with the workpiece supported on the worktable such that the multiple spindle unit or the single tool on a tool spindle performs the machining operation on the workpiece.

Abstract: A Z-axis drive assembly for a turret machining center incorporates a variable speed DC motor mounted on a vertically adjustable carriage and connected through a harmonic drive unit to rotate a pinion. The pinion forms part of a rack and pinion mechanism, for controlling the vertical elevation of the rack relative to the carriage.

Abstract: An improved portable bracket assembly capable of being attached to a milling machine to thereby allow a plurality of sequentially located tool holders to be selected and inserted into the spindle of the milling machine. A special camming device containing a plurality of settable cams, one for each tool holder, and synchronized with the movement of said tool holders, controls selected switches. The presettable cams allow the first switch to continuously engage the indexing means driving the tool holders should a tool holder not contain a cutting tool. The resettable cams also control a second switch mechanism for creating a specific tool speed control signal for the specific tool in each tool holder.

Abstract: A turret head for a rotary turning machine having a base rotatably mounted on a cross-slide for movement about a first axis. The turret head is mounted to the base for rotatable movement relative thereto about a second axis that is inclined to the first axis by an angle .alpha.. The turret head includes two rings or annular arrays of tool holders. Each ring has its tools disposed so that their axes lie on the surface of an imaginary cone having a vertex angle of 2.beta., such that .alpha. + .beta. = 90.degree.. The two imaginary cones have their axes coincide with the second axis and preferably the vertices of the cones coincide, so that the cones are mirror images of each other.