SKIDDING METHOD AND MACHINE Russian patent published in 2004 - IPC

FIELD: forest industry and forestry, in particular, tree harvesting equipment and processes. SUBSTANCE: known method involves forming bundles of individual trees to be forwarded by means of, for example, felling-bunching machines and forwarding of bundles by means of skidding tongs. Known skidding machine has self-propelled chassis, arch mounted on chassis and equipped with tilting drive, rocker boom equipped with drive and incorporating skidding tongs on its rear free end, and hoist positioned forward of arch. One end of hoist cable is fixed on winch drum and other end is passed through pulley mounted on arch and coupled to skidding tongs. Said method and machine may be used only for skidding of formed bundles, so two machines are supposed to be used and, consequently, probability of disturbing soil mantle, damage to underbrush and root system and adjoining trees is increased, which is undesirable for gradual felling and cleaning cuttings. Proposed method involves forming bundles of individual trees and forwarding said bundles by means of single machine in two stages, first stage including fixing pulley on standing tree by means of rocker boom, passing cable with chokers through pulley from standard machine hoist and skidding trees into bundles, and second stage including skidding formed bundles by means of the same machine but with the help of skidding tongs. Skidding machine has rocker boom equipped with additional link connected to rocker boom for rotation in vertical longitudinal plane of machine by means of drive. Skidding tongs are mounted at rear end of rocker boom. Grapple equipped with drive and tilting pulley are mounted on free end of additional link. Hoist cable is passed through tilting pulley. Bracket is rigidly fixed on top of rocker boom front end so that bracket may be clamped by grapple in folded position of additional link as bundles are skidded by skidding tongs. Grapple is immovably mounted on additional link and provided with single movable grab. Tilting pulley is mounted on immovable grab of grapple. EFFECT: wider range of use, reduced number of passes performed by machine to result in reduced damage to soil mantle, underbrush and root system of adjacent trees. 4 cl, 6 dwg