Crosshead for sabre saws and sabre saws incorporating same

摘要

A crosshead for a scotch yoke mechanism is formed from a generally rectangular blank of sheet steel provided with a generally oval, straight sided opening extending generally transversely medially thereof and a pair of generally circular openings centered and spaced apart from each of the oval opening straight sides, the blank being formed, as on a four slide forming machine generally around two generally parallel lines each being generally extensions of the oval opening straight sides to provide top and bottom generally parallel panels defining a closed end guide track having parallel sides and positioning the generally circular openings in the top and bottom panels and in line to be threaded on a generally cylindrical tubular saw bar of a sabre saw, the blank being further formed to tubular configuration of generally rectangular cross- section by two further parallel bends closing the crosshead on a fourth side on the side of the saw bar opposite the guide track opening. The crosshead is povitally mounted on the saw bar, a pair of low mass snap or clinch rings disposed in annular grooves on the saw bar on opposite sides of the crosshead adjacent the top and bottom panels.