Abstract: An eight cylinder rotary Stirling cycle engine ncludes first and second cylinder banks each comprising four cylinders having a fire box about the upper end of the cylinders and cooling fins about the lower end of the cylinders. The four cylinders of each bank are disposed about the centrally located longitudinal axis of each cylinder bank. A spacer divides each cylinder into a displacer cylinder and a power cylinder. A power piston and a displacer piston are disposed respectively in the power cylinder and the displacer cylinder and are rigidly connected together by a shaft. The lower porton of each displacer cylinder includes a displacer port, while the upper portion of each power cylinder includes a power port. A crossover pipe couples the displacer port of one displacer cylinder to a power port in an adjacent power cylinder. Since one of the two coupled cylinders is operating 90.degree.

Abstract: A hydraulically operated pivotable cutting tool extends from a machine tool depending from the collet of a rigid spindle machine. The machine tool selectively develops a source of hydraulic fluid under pressure for laterally positioning the cutting tool and for effecting pivotal movement of the cutting implement attached to the cutting tool.

Abstract: A rotating machine tool for hydraulically positioning a cutting tool mounting assembly lateral to the axis of rotation is disclosed. A collar circumscribing the axis of rotation and having an inclined annular downwardly directed recess is slidably mounted on the machine tool. A pair of diametrically opposed plungers ride within the inclined recess and are forced into reciprocal movement thereby. The reciprocating plungers pump hydraulic fluid from a reservoir within the machine tool into a pressure chamber. The pressure chamber is connected to a piston and cylinder assembly, which piston is positionally responsive to the pressure within the chamber. The movement of the piston is translated into lateral movement of the cutting tool via a spring biased mounting assembly. In operation, the rotation of the collar is restrained while the body of the machine tool rotates.