GB653179A - Improvements in and relating to machines for sawing timber - Google Patents

Abstract

653,179. Chain saws. ALEXANDER, H. J., and TELES SMITH, Ltd. March 12, 1948, No. 7566. [Class 145(ii)] A machine for ripping timber comprises horizontal rods positionable on either side of the lying timber on which runs a wheeled carriage provided at each side of the timber with vertical guides means, a stage on each of said guide means for supporting one end of a chain-saw unit and means for vertically adjusting the stages together. The machine comprises horizontal chassis members 8 having grooved wheels 9 which run on rails 1 mounted on sleepers 1a. Each member 8 has a pair of vertical guides 10 mounted on it which are braced at their upper ends by a spanning frame 11. Mounted between the guides are stages 12, 13, the stage 12 carrying the motor unit of a motor driven chain-saw and the stage 13 carrying the chain wheel housing at the other end of the saw. The stages may be raised or lowered simultaneously by cable 17, 18 anchored to drums 11b, 11c which are mounted on a shaft 11a, bushed in spanning member 11, and rotated by a handwheel 19. A rachet and pawl .mechanism 20 is fixed to the shaft for checking counter rotation. The carriage is moved longitudinally to feed the saw into the log by cables 21 anchored to drums 5 which are mounted on a shaft 4, bushed in strutting posts 3, and rotated by a handwheel 6. The shaft 4 is provided with a ratchet and pawl 7. Several interchangeable ratchets may be fitted at 20, each having differently spaced teeth to vary the thickness of the plank cut. Racks and pinions may .be fitted for the longitudinal and vertical adjustments of the stage instead of cables, and the vertical adjustment may be made with linear ratchet racks and pawls. Specification 638,217 is referred to.