Abstract: A machine for forming an annular counterbore in the outer face of the solid end of a piston has a tool supporting spindle rotated on its own central axis and simultaneously revolved about an eccentric axis, the eccentricity of the axis of revolution being adjustable to accommodate pistons of different diameters.

Abstract: A lathe type piston turning machine wherein a single point cutting tool is controlled simultaneously by two separate cams to generate a desired contour on a piston which varies in both radial and axial cross section.

Abstract: A boring machine has two spindle driven boring bars mounted on a common slide and supported by separate quills, each of which is movable relative to the slide. A stop on each quill locates its respective boring bar relative to a locating surface on the workpiece so that a cutting tool on each boring bar can be fed radially to machine the face of a counterbore at the desired depth relative to the locating surface on the workpiece. The machine includes a compensating mechanism for adjusting the cutting tools on each boring bar to compensate for tool wear.

Abstract: A workpiece transfer machine of the type including a plurality of regularly spaced machining stations is disclosed. Workpieces are advanced to the successive machining stations by means of a transfer bar powered to have a rectangular walking beam motion. The transfer bar is provided with nests or carriers for supporting the workpieces and is adapted to be retracted and remain in a position wherein the nests are located midway between the machining stations while the workpieces are being machined.

Abstract: A machine tool having a boring bar carrying cutting tools and mounted for rotative adjustment on a rotary driven spindle with its axis offset from the axis of the spindle. An additional cutting tool is mounted for radial adjustment on the spindle individually of the boring bar. The tools on the boring bar and the cutting tool on the spindle are adjusted radially by means of a helically splined nut engaged with a similarly splined shaft which is rotated relative to the spindle in response to axial displacement of the shaft.

Abstract: A lathe type machine for turning pistons, in which the cutting tool is caused to follow the surface contour of the cam which corresponds in shape to the desired contour of the piston to be machined. The cutting tool and a cam follower are mounted in spaced relation on an arm supported on a tool slide by means of an eccentric pivot pin, which when rotated in opposite directions shifts the tool toward and away from the axis of the work supporting spindle. Means are provided for automatically rotating the eccentric pivot pin through an arc of fixed angular extent in one direction when the tool slide reaches one end of its stroke and in the opposite direction through the same arcuate extent when the tool slide reaches the other end of its stroke. Means are also provided for rotating the eccentric pin slightly when desired to effect a change in size without affecting the extent of arcuate movement of the pin at opposite ends of the stroke of the tool slide.