TREE SHEAR ACTUATOR RESTRAINT SYSTEM

摘要

TREE SHEAR ACTUATOR RESTRAINT SYSTEM A tree shear head includes a frame which supports a pair of parallel crank shafts which are respectively linked to a pair of shear blades for moving the latter together into the trunk of a tree being sheared. The crank shafts are rotated by means of an actuator including a cylinder in which a pair of piston and piston rod units are mounted with the rods projecting oppositely and being respectively pivotally connected to a pair of crank arms respectively formed integrally with the pair of crank shafts. To prevent the cylinder of the actuator from shifting axially along the piston rods, a pair of links are connected between the cylinder and the frame, and for preventing the cylinder from rotating about the piston rods, a pair of rollers are mounted on the cylinder and engage the frame.