A control system configured to control movement of a hydraulically operated crane assembly and a crane tool of a work vehicle with a primary power source and a hydraulic working system. The control system configured to calculate a deviation between an actual value and a predetermined target value of a lifting movement of the crane assembly, and configured to control the crane assembly to fulfill the predetermined target value.

A device for picking up and hauling a log or similar object and a method for its use are disclosed. The device is capable of picking up one end of the log and dragging the log behind it, but is also capable of picking up the entire log off the ground. The device can be anchored to and pulled behind a small vehicle, such as an all-terrain vehicle (ATV) or utility vehicle (UTV), or behind a large vehicle such as a car or truck. The device uses no winches or hydraulics that could break or wear out, and lifts and holds the log solely using levers and chains as attachment points. The device is able to maneuver over rugged terrain and is also able to be towed at high speeds on a road.

A device for picking up and hauling a log or similar object and a method for its use are disclosed. The device is capable of picking up one end of the log and dragging the log behind it, but is also capable of picking up the entire log off the ground. The device can be anchored to and pulled behind a small vehicle, such as an all-terrain vehicle (ATV) or utility vehicle (UTV), or behind a large vehicle such as a car or truck. The device uses no winches or hydraulics that could break or wear out, and lifts and holds the log solely using levers and chains as attachment points. The device is able to maneuver over rugged terrain and is also able to be towed at high speeds on a road.

An improved articulated heavy haul trailer combination comprises a trailing accessory vehicle such as a booster coupled to a main trailer by a coupling. The coupling includes a horizontal hinge, a vertical hinge that allows the trailing accessory vehicle to yaw in a horizontal plane, a spreader extending between the hinges and a hydraulic piston and cylinder. A turn sensor mounted on said combination detects yawing, and a controller reduces the piston and cylinder's downward biasing force on the coupling.

A grapple for handling logs includes a base portion connectable to a working machine portion and at least one tine connected to the base portion. The at least one tine has a protruding length from the base portion. The grapple further includes a catch arm pivotably arranged relative to the base portion. The grapple can assume configurations with different protruding lengths of the at least one tine.

Method and apparatus for an extendable logging trailer constructed of left and right main I-beam members having left and right male telescoping beams moving on rollers on the bottom inner flange of the main I-beam members. The male telescoping beams allow the trailer to be retractable or extendable so that it can assist in offloading the logs/pipes from the logging trailer. In operation, a front bolster and push rack are moved in unison by a first hydraulic cylinder toward the rear of the trailer at the same time as a rear bolster is moved by a second hydraulic cylinder toward the front of the trailer thereby causing the length of the trailer to shorten. As the trailer shortens, the logs/pipes which are carried on the bolsters are forced toward the rear of the trailer so that gravity eventually causes the rear ends of the logs/pipes to fall downwardly toward the ground which allows the operator of the tractor which is pulling the logging trailer to move the logging trailer forwardly causing the logs/pipes to become completely offloaded from the logging trailer.

Method and apparatus for an extendable logging trailer constructed of left and right main I-beam members having left and right male telescoping beams moving on rollers on the bottom inner flange of the main I-beam members. The male telescoping beams allow the trailer to be retractable or extendable so that it can assist in offloading the logs/pipes from the logging trailer. In operation, a front bolster and push rack are moved in unison by a first hydraulic cylinder toward the rear of the trailer at the same time as a rear bolster is moved by a second hydraulic cylinder toward the front of the trailer thereby causing the length of the trailer to shorten. As the trailer shortens, the logs/pipes which are carried on the bolsters are forced toward the rear of the trailer so that gravity eventually causes the rear ends of the logs/pipes to fall downwardly toward the ground which allows the operator of the tractor which is pulling the logging trailer to move the logging trailer forwardly causing the logs/pipes to become completely offloaded from the logging trailer.

The invention relates to a forest machine, comprising a chassis having a first chassis and a second chassis pivoted consecutively by a central pivot, first sets of wheels arranged in connection with the first chassis, an engine fitted in connection with the first chassis, a load space supported on the second chassis extending at least partly below an upper surface of the second sets of wheels, power transmission transmitting power to the second drive wheel of the second sets of wheels, wherein the second chassis includes two longitudinal parts attached to each other at least in front of the load space, which longitudinal parts are at a distance from each other in lateral direction of the forest machine at least over a partial length of the load space, in which forest machine the load space extends between the longitudinal parts in vertical direction of the forest machine.

The invention relates to a forest machine, comprising a chassis having a first chassis and a second chassis pivoted consecutively by a central pivot, first sets of wheels arranged in connection with the first chassis, an engine fitted in connection with the first chassis, a load space supported on the second chassis extending at least partly below an upper surface of the second sets of wheels, power transmission transmitting power to the second drive wheel of the second sets of wheels, wherein the second chassis includes two longitudinal parts attached to each other at least in front of the load space, which longitudinal parts are at a distance from each other in lateral direction of the forest machine at least over a partial length of the load space, in which forest machine the load space extends between the longitudinal parts in vertical direction of the forest machine.

A support arm for a loading bunk of a transport vehicle, having a horizontal and a vertical section, each section comprising an inner and outer segment, which are telescopically connected to each other so that the length of the vertical and horizontal sections is variable. Each section further comprising an inner hydraulic actuator with at least one hydraulic pressure chamber, connected to the segments of the horizontal and vertical sections so that movement of the hydraulic actuators changes the lengths of the vertical and horizontal sections respectively. The vertical section being fixedly connected to the horizontal section on one end of the inner or outer segment.