Abstract: An articulated boom assembly is mounted on a vehicle for swinging movement about a vertical axis. A shear-grapple unit is pivotally attached to the free end of the boom assembly so that after a standing tree has been cut, it may be tilted from a vertical position to a horizontal position. When the cut tree is positioned horizontally above the vehicle, it can be lowered into a stationary delimbing head and also at the same time to a clamping mechanism that travels longitudinally of the vehicle for the purpose of feeding the tree toward a shear mechanism, the delimbing of the tree taking place as this is done. When advanced to a predetermined distance beyond the shear mechanism, the shear mechanism is actuated to sever the first bolt which drops onto an inclined annular plate that has a U-shaped yoke projecting upwardly through its central opening. When the yoke is rotated through 90.degree., a spring yields under the weight of the bolt so that the bolt is free to roll into a collector.

Abstract: A V belt pulley clutch assembly for a variable speed transmission which may be either the driving or the driven pulley, and which has one movable sheave which is both speed and torque responsive, and wherein the torque responsive portions comprise raised spiral ramps on the hub of the movable portion of the V belt pulley driven through saddle type members riding on the spiral ribs. The ribs are spiraled axially along the hub of the movable portion of the V belt pulley in a direction so that when the driven member is subjected to more load the unit tends to shift into a lower drive ratio. That is when the drive clutch assembly is powered from a drive shaft, the spirals are arranged so that the pulley halves tend to separate under increasing load on the belt. The ribs are on the external surface of a hub and can be die cast draft free for permitting driving and sliding between two relatively movable pulley halves.

Abstract: A safety switch system for use on snowmobiles that eliminates the hazards of previous systems by providing series connected normally closed switches, one connected directly into the throttle control lever which the operator must press for increasing engine speed from idle, and the other mounted directly on the carburetor and controlled by the throttle control arm which is directly connected to the butterfly valve of the carburetor. The two switches are connected to an engine kill system, such as a ground circuit for the ignition. One of the switches must be open for the engine to be running. This means that when the throttle is open (the carburetor control arm is away from idle position) and the operator's hand is off the throttle control lever the engine is dead. However, with the throttle arm in idle position the engine will run whether the operator has his hand on the manual throttle control lever or not.