Patent Description:
Forestry machines are used in mechanised harvesting for felling, delimbing, cutting to size, collecting, transporting and stacking trees. Forestry machines include e.g. harvesters, forwarders and their combinations, the so-called combined machines. Harvesters are used in mechanised harvesting for felling, delimbing and cutting trees to size. By means of harvesters, timber is typically stacked in suitable work piles by timber assortment in the felling area. Correspondingly by means of forwarders, timber is typically collected from the work piles, transported to the side of a road and unloaded into timber piles. Combined machines can handle the operations of both, i.e. harvesters and forwarders.

Forestry machines, such as forwarders and combined machines, are off-road work machines which collect timber from various work piles or stacks to be transported to the side of a road to be unloaded into various timber piles.

On the side of the road, the timber piles should be neat and the ends of said timber piles should be even. The evenness of the ends of timber piles is a safety issue and also aesthetically desirable. When the ends of timber piles are even, it is easier to transfer timber for transport onto e.g. road vehicles.

A traditionally used manner of controlling the unloading of a forestry machine operates such that a driver of the forestry machine controls the unloading of a timber load into a timber pile by manual controls. The driver of the forestry machine should be particularly attentive for making the end of the timber pile even. International specification <CIT> describes a prior-art arrangement for controlling the unloading of a forestry machine. European specification <CIT> also describes another prior-art arrangement for controlling the unloading of a forestry machine. Furthermore, Finnish specification <CIT> describes a prior-art arrangement for controlling the boom structure of a forwarder. Additionally, Finnish utility model <CIT> describes a prior-art arrangement for controlling a timber feeder. Furthermore, KHT Doctoral Thesis by Björn Löfgren "Kinematic Control of Redundant Knuckle Booms with Automatic Path-Following Functions" describes a Kinematic Simulator Software (KSS) and a Dynamic Forest Machine Simulator (DFMS), which simulator arrangements are then further studied and analyzed. However, it is not possible by means of arrangements described in said specifications to provide sufficiently even unloading of a timber load into a timber pile. The even unloading of a timber load into a timber pile by means of the manual control according to prior art has thus proved extremely time-consuming and awkward.

Indeed, there is a clear need for an arrangement which provides a more controllable, time-saving and reliable arrangement in unloading timber loads into timber piles than the previous arrangements.

The purpose of this invention is to provide a novel kind of an arrangement for controlling the unloading of a forestry machine, by means of which, it is possible to achieve a more controllable, time-saving and reliable arrangement in unloading timber loads into timber piles than the previous arrangements e.g. on the side of a road and, by means of which, problems and disadvantages in unloading timber loads can be minimised.

It is characteristic of an arrangement according to the invention for controlling unloading of a forestry machine, in which the forestry machine comprises a load space for a timber load, a boom structure and a wood-handling tool attached to said boom structure, which arrangement further comprises a control system and a measuring apparatus of the forestry machine in which said measuring apparatus is arranged to measure the location of the forestry machine and the rotation angle of the boom structure and the position of the single boom parts of the boom structure and the position of the wood-handling tool; and in which: said control system is arranged: to define and note down the location of a timber pile, to calculate and note down the location of an edge of the timber pile, to control the wood-handling tool to pick a timber bundle from the timber load, to calculate the distance of an end justified to a load screen of said timber bundle from the wood-handling tool, to calculate an unloading location for said timber bundle into a timber pile even and straight of its one edge in the defined timber pile location, and to control and unload said timber bundle in said calculated unloading location in the timber pile.

Preferably, said measuring apparatus is arranged to measure the motion space of single boom parts of the boom structure.

Preferably, said measuring apparatus is arranged to measure the rotation angle of the wood-handling tool.

Preferably, said control system is arranged to control the rotation angle of said boom structure and the position of single boom parts of the boom structure and the location of said wood-handling tool.

Preferably, said measuring apparatus is arranged to measure the position of grabbing means of the wood-handling tool.

Preferably, said control system is arranged to identify and/or control the position of the grabbing means of the wood-handling tool.

Preferably, said control system is arranged to calculate the height of the timber pile based on the unloading location of unloaded timber bundles.

Preferably, said control system is arranged to automatically identify the location of the forestry machine and/or the location of the timber-pile.

Preferably, said control system is arranged to automatically identify the position of the boom structure of the forestry machine and/or its rotation angle by identifying the position and/or motion space of single boom parts.

Preferably in the arrangement, said forestry machine is a forwarder.

It is characteristic of a method according to the invention for controlling unloading of a forestry machine, in which the forestry machine comprises a load space for timber load, a boom structure, a wood-handling tool attached to said boom structure, a control system and a measuring apparatus, in which the method comprises the steps of: defining and noting down the location of a - timber pile, calculating and noting down the position of an edge of the timber pile, picking by the wood-handling tool a timber bundle from the timber load, calculating the distance of an end justified to a load screen of said timber bundle from the wood-handling tool, calculating an unloading location for said timber bundle into a timber pile even and straight of its one edge in the defined timber pile location, and controlling and unloading said timber bundle in said calculated unloading location in the timber pile.

Preferably, the location of the timber pile is noted down by picking a timber bundle from the timber load of said load space and by transferring and unloading said timber bundle on the first edge of the timber-pile location.

Alternatively, the location of the timber pile is noted down by picking a first timber bundle from the timber load of said load space and by transferring and unloading said first timber bundle on the first edge of the timber-pile location and by picking a second timber bundle from the timber load of said load space and by transferring and unloading said second timber bundle on the second edge of the timber-pile location.

Preferably, the method comprises a step for controlling the wood-handling tool controlled against the screen against the load screen and registering the location of said load screen down.

Preferably in the method, said forestry machine is a forwarder.

Some embodiments of the invention will now be described in greater detail by means of some preferred embodiments, with reference to the attached drawings, in which.

The figures are not to scale, and some features may have been simplified, emphasised or faded out to improve the clarity of the essential features of the figures.

<FIG> is a perspective view of a forestry machine according to an embodiment of the invention. <FIG> shows a forestry machine <NUM> according to an embodiment according to the invention, in more detail a forwarder <NUM>. The forestry machine <NUM> according to the invention is described here without a timber load. In different embodiments, the forestry machine <NUM> can also comprise another forestry machine, e.g. a combination of a forwarder and harvester or another drive machine suitable for carrying a load.

The forestry machine <NUM> according to an embodiment of the invention can comprise a load space <NUM> for stacking a timber pile to be transported. The forestry machine <NUM> can additionally comprise a boom structure <NUM> and a wood handling tool attached to the boom structure <NUM>, such as a load bucket. Furthermore, the forestry machine <NUM> can comprise a rotating pivot device, the so-called rotator, arranged between said boom structure <NUM> and said wood-handling tool. Additionally, the forestry machine <NUM> can comprise a cabin <NUM> and a load screen <NUM> arranged on the end of the cabin <NUM> in the load space <NUM>. The forestry machine <NUM> according to an embodiment of the invention is arranged to collect timber from the work piles of the felling location, to transport the collected timber load to the side of a road and to unload the timber load into timber piles.

The forestry machine <NUM> can further comprise a moving means <NUM>, which moving means <NUM> may comprise at least one of the following: wheels arranged on an axle, wheels arranged on a swinging axle, wheels arranged on a tandem axle, a track system or another means known as such to cause the forestry machine to move in relation to its working surface. It is obvious for those skilled in the art that typically the work machine additionally comprises numerous structural and functional components and entities that depend on the work machine type, such as a power source and so forth.

The forestry machine <NUM> comprises an arrangement for controlling the unloading of the forestry machine. By means of the control arrangement of the unloading of a forestry machine according to the invention the driver is assisted in the unloading of a timber load <NUM> of the forestry machine <NUM> such that the timber load <NUM> can be cleanly unloaded into timber piles into a desired timber-pile location <NUM>.

<FIG> shows a top view of an illustration of an arrangement according to an embodiment of the invention for controlling the unloading the load of a forestry machine. In an arrangement , driver of a forestry machine <NUM>, such as a forwarder <NUM>, selects/identifies a suitable location <NUM> for a timber pile, e.g. a timber-pile location <NUM> on the side of a road. The driver controls the forestry machine <NUM> into an area <NUM> next to said timber-pile location <NUM>. In an arrangement according to an embodiment of the invention, the timber load <NUM> in the load space <NUM> of the forestry machine <NUM> has already been justified in the loading step such that the ends of timber are evenly against a load screen <NUM> of the load space <NUM> of the forest machine <NUM>.

In an arrangement, the driver of a forestry machine <NUM> notes down a timber-pile location <NUM> by means of the boom structure <NUM> of the forestry machine <NUM> and the wood-handling tool <NUM> attached to said boom structure <NUM>. The noting down of the timber-pile location <NUM> can be done e.g. by picking a timber bundle <NUM> from the timber load <NUM> of the load space <NUM> of the forestry machine <NUM> and by transferring (Arrow A) and unloading said timber bundle <NUM> on the first edge of the timber-pile location <NUM>, on the left edge in <FIG>. In the arrangement according to the invention, the control system of the forestry machine <NUM> then reads that the timber-pile location <NUM> starts from said unloading location of the timber bundle <NUM>. The control system of the forestry machine <NUM> can also read that the filling direction of the timer pile is in the direction of said unloading location of the timber bundle <NUM> towards the forestry machine <NUM>, starting from the left edge to the right in <FIG>. Alternatively, the driver can notify of the filling direction of the timber pile to the control system in some other way, e.g. by a separate command or a certain predetermined control motion. If the driver so desires, they can justify the timber bundle <NUM> against the load screen <NUM>, if the ends have not been straight against the load screen <NUM>. Preferably, this justifying motion of the timber bundle against the screen can be an automatic or a semiautomatic action. Preferably in connection with this action, the grabbing means of the wood-handling tool <NUM>, e.g. the jaws of a grabber are opened, whereby it is possible for the single timbers in the bundle to justify in the bundle onto the same level.

In an arrangement according to an embodiment of the invention, the control system of the forestry machine <NUM> always identifies the location of the wood-handling tool <NUM> and is able to control the position of the wood-handling tool <NUM> and the rotation angle of the wood-handling tool <NUM>. The position of the wood-handling tool <NUM> can be calculated based on sensor measuring data, such as on sensor data of the boom structure, or in some other way. Furthermore, the control system of the forestry machine <NUM> is arranged to identify and/or control the position of the grabbing means of the wood-handling tool <NUM>, e.g. the position of the jaws of a grabber.

When the forestry machine <NUM> picks by the wood-handling tool <NUM> a timber bundle from the timber load <NUM> of the load space <NUM>, the control system of the forestry machine <NUM> knows beforehand the location of the load screen <NUM> and, thus, also the distance of the end of a timber bundle justified against the load screen from the wood-handling tool <NUM>. The control system can know that location of the load screen <NUM> e.g. such that the driver controls that wood-handling tool <NUM> against the screen and commands the control system to register the location of the load screen <NUM> down. Justifying the timber bundle <NUM> can be acknowledged by the grabber closed action because, when justifying the ends, the wood-handling tool <NUM> must be opened slightly.

In an arrangement according to an embodiment of the invention, when the forestry machine <NUM> picks a timber bundle from the timber load <NUM> of the load space <NUM>, the measuring apparatus of the forestry machine <NUM> measures and/or identifies the distance of the end of a timber bundle justified against the load screen <NUM> from the wood-handling tool <NUM>. When the forestry machine <NUM> picks a timber bundle from the timber load <NUM> of the load space <NUM>, the control system of the forestry machine <NUM> knows the distance of the end of a timber bundle from the wood-handling tool <NUM>. The control system of the forestry machine <NUM> thus knows with the aid of the measuring apparatus the distance of the wood-handling tool <NUM>, e.g. a grabber, from the screen irrespective of in which position of the timber load <NUM> of the load space <NUM> the wood-handling tool <NUM> picks timber. When the driver takes the first timber bundle <NUM> into the timber pile of the timber-pile location <NUM> and opens the wood-handling tool <NUM>, the control system calculated and notes down the location of the edge of the timber pile. Then, the control system can help the driver to take each timber bundle at an accurate distance from the machine and the edge of the timber pile becomes even and straight.

In an arrangement according to an embodiment according to the invention, the control system of the forest machine <NUM> can also calculate the height of the timber bundle based on the previous unloading location of the timber bundles <NUM> of the wood-handling tool <NUM> and thus adjust the unloading height of the wood-handling tool <NUM> for each timber bundle <NUM> almost accurate. In an arrangement according to an embodiment of the invention, the control system of the forestry machine <NUM> can control the rotation angle of the wood-handling tool <NUM> e.g. by means of the rotation angle of the rotator. Hence, the control system of the forestry machine <NUM> also knows the accurate direction of the bundle and the system can turn the timbers in the timber bundle <NUM> automatically parallel with the pile and the timbers of the timber bundle <NUM> stay at an angle of <NUM> degrees in relation to the side of the pile.

When in the arrangement according to an embodiment of the invention the timber-pile location <NUM> has been designated, the control system of the forestry machine <NUM> automatically assists in controlling and unloading of the timber pile <NUM>. The control system of the forestry machine <NUM> calculates a suitable unloading location for each timber bundle picked from the timber load <NUM> of the load space <NUM> of the forestry machine <NUM> by means of the wood-handling tool <NUM> and controls said timber bundles a bundle at a time into the calculated unloading location neatly in a timber pile. Hence, a timber pile even and/or straight of its one edge can be provided into a designated timber-pile location <NUM>. When the timber load <NUM> has been unloaded into the timber pile of the timber-pile location <NUM>, the forestry machine <NUM> can leave to pick a new load from the felling area.

In an arrangement according to an embodiment of the invention, the forestry machine <NUM> return with a new timber load back to close to the timber-pile location <NUM> on the side of a road. When the driver controls the forestry machine <NUM> in an area <NUM> next to said timber-pile location <NUM>, the control system of the forestry machine <NUM> automatically identifies the location of the forestry machine <NUM>, preferably in relation to the timber pile and the location of the timber-pile location <NUM>, and reads that the forestry machine <NUM> has returned with a new timber load <NUM>. Furthermore, the control system of the forestry machine <NUM> remembers the filling situation of the timber pile in the timber-pile location <NUM> and automatically assists in unloading the new timber load <NUM> neatly in the timber pile and controls the timber bundles picked from the timber load <NUM> of the load space <NUM> of the forestry machine <NUM> by means of the wood-handling tool <NUM> a bundle at a time into an even timber pile in the designated timber-pile location <NUM>. Additionally, the driver can notify the control system of some control command related to the filling of the timber pile e.g. by a separate command or a certain predetermined control motion.

<FIG> shows a block diagram of the structure of a control arrangement of unloading of a forestry machine according to an embodiment of the invention. The control arrangement <NUM> of the unloading of a forestry machine according to an embodiment of the invention comprises a control system <NUM>, a measuring apparatus <NUM> and actuators <NUM> of the forestry machine. The measuring apparatus <NUM> of the control arrangement <NUM> according to the invention comprises at least two measuring devices <NUM>-<NUM>, by means of which, it is possible to measure some required measuring variables, such as e.g. the location of the forestry machine <NUM>, preferably in relation to the timber pile, the position of the wood-handling tool <NUM>, preferably in relation to the timber pile and the forestry machine <NUM> and its rotation angle and the location and rotation angle of the timber bundle picked by means of the wood-handling tool <NUM>. Said at least two measuring devices <NUM>-<NUM> of the measuring apparatus <NUM> can comprise at least one GPS measuring device <NUM> for defining the location of the forestry machine <NUM>.

<FIG> shows a block diagram of a method according to an embodiment of the invention for controlling the unloading of a forestry machine. In a method for the unloading of the load of a forestry machine, the driver first selects/identifies a suitable location <NUM> for the timber pile, e.g. a timber-pile location <NUM> on the side of a road, and controls the forestry machine <NUM> close to the timber-pile location they have selected/identified <NUM>.

Next, the control system <NUM> of the forestry machine <NUM> identified <NUM> if the timber-pile location has been previously designated or not. If the timber-pile location has not been designated previously, the timber-pile location is next designated <NUM>. In a method described according to an embodiment of the invention, the driver of a forestry machine <NUM> notes down a timber-pile location <NUM> by means of the boom structure <NUM> of the forestry machine <NUM> and the wood-handling tool <NUM> attached to said boom structure <NUM>. The start edge of the timber-pile location can be designated <NUM> e.g. by picking a timber bundle <NUM> from the timber load <NUM> of the load space <NUM> of the forestry machine <NUM> and by transferring and unloading said timber bundle <NUM> on the start edge of the timber-pile location <NUM>. After having designated <NUM> the timber-pile location, it is possible to transfer to the unloading step <NUM>-<NUM> of the timber load. Also correspondingly, if the control system <NUM> in the identifying step identifies <NUM> that the timber-pile location has been designated previously, it is possible to transfer to the unloading step <NUM>-<NUM> of the timber load.

Next in the unloading step <NUM>-<NUM> of the timber load, the forestry machine <NUM> picks <NUM> by the wood-handling tool <NUM> a timber bundle from the timber load <NUM> of the load space <NUM>. When the timber pile has been picked <NUM> to the wood-handling tool <NUM>, the control system <NUM> of the forestry machine <NUM> calculates <NUM> a suitable unloading location for the timber bundle in question and controls said timber bundles a bundle at a time into the calculated <NUM> suitable unloading where the timber bundle is unloaded <NUM> neatly in a timber pile. When the timber load has been unloaded empty <NUM> into the timber pile of the timber-pile location <NUM>, the unloading step <NUM>-<NUM> is stopped and the forestry machine <NUM> can leave to pick a new load from the felling area.

<FIG> shows a top view of an illustration of an alternative arrangement according to an embodiment of the invention for controlling the unloading the load of a forestry machine. In an alternative arrangement according to an embodiment of the invention, the driver of a forestry machine <NUM>, such as a forwarder <NUM>, selects/identifies a suitable location <NUM> for a timber pile and control the forestry machine <NUM> in an area <NUM> next to said timber-pile location <NUM>. The driver of the forestry machine <NUM> designated the timber-pile location <NUM> by means of the boom structure <NUM> of the forestry machine <NUM> and the wood-handling tool <NUM> attached to said boom structure <NUM>.

In an arrangement according to an alternative embodiment of the invention, the noting down of the start edge of the timber-pile location <NUM> can be done e.g. by picking a first timber bundle <NUM> from the timber load <NUM> of the load space <NUM> of the forestry machine <NUM> and by transferring (Arrow A) and unloading said first timber bundle <NUM> on the first edge of the timber-pile location <NUM>, on the left edge in <FIG>. Similarly, the noting down of the stop edge of the timber-pile location <NUM> can be done e.g. by picking a timber bundle <NUM> from the timber load <NUM> of the load space <NUM> of the forestry machine <NUM> and by transferring (Arrow B) and unloading said timber bundle <NUM> on opposite second edge of the timber-pile location <NUM>, on the right edge in <FIG>.

In the arrangement according to the invention, the control system of the forestry machine <NUM> then reads that the timber-pile location <NUM> starts from said unloading location of said first timber bundle <NUM> and stops in said unloading location of the second timber bundle <NUM>. The control system of the forestry machine <NUM> can also thus read that the timber pile can be filled evenly between the above-mentioned unloading location of the timber bundles <NUM>, <NUM>.

When in the arrangement according to an alternative embodiment of the invention the timber-pile location <NUM> has been designated, the control system of the forestry machine <NUM> automatically assists in controlling and unloading of the timber pile <NUM>. The control system of the forestry machine <NUM> calculates a suitable unloading location for each timber bundle picked from the timber load <NUM> of the load space <NUM> of the forestry machine <NUM> by means of the wood-handling tool <NUM> and controls said timber bundles a bundle at a time into the calculated unloading location neatly in a timber pile. Hence, a timber pile even and/or straight of its one edge can be provided into a designated timber-pile location <NUM>. When the timber load <NUM> has been unloaded into the timber pile of the timber-pile location <NUM>, the forestry machine <NUM> can leave to pick a new load from the felling area. In an arrangement according to an embodiment of the invention, the forestry machine <NUM> return with a new timber load back to close to the timber-pile location <NUM> on the side of a road. When the driver controls the forestry machine <NUM> in an area <NUM> next to said timber-pile location <NUM>, the control system of the forestry machine <NUM> automatically identifies the location of the forestry machine <NUM>, preferably in relation to the timber pile and the location of the timber-pile location <NUM>, and reads that the forestry machine <NUM> has returned with a new timber load <NUM>. Furthermore, the control system of the forestry machine <NUM> remembers the filling situation of the timber pile in the timber-pile location <NUM> and automatically assists in unloading the new timber load <NUM> neatly in the timber pile and controls the timber bundles picked from the timber load <NUM> of the load space <NUM> of the forestry machine <NUM> by means of the wood-handling tool <NUM> a bundle at a time into an even timber pile in the designated timber-pile location <NUM>. Additionally, the driver can notify the control system of some control command related to the filling of the timber pile e.g. by a separate command or a certain predetermined control motion.

<FIG> shows a block diagram of a method according to an embodiment of the invention for controlling the unloading of a forestry machine. In a method for the unloading of the load of a forestry machine, the driver first selects/identifies a suitable location <NUM> for the timber pile, e.g. a timber-pile location <NUM> on the side of a road, and controls the forestry machine <NUM> close to the timber-pile location they have selected/identified <NUM>. Next, the control system <NUM> of the forestry machine <NUM> identifies <NUM> if the timber-pile location has been previously designated or not. If the timber-pile location has not been designated previously, the timber-pile location is next designated <NUM>, <NUM>. In a method described according to an embodiment of the invention, the driver of a forestry machine <NUM> notes down <NUM>, <NUM> a timber-pile location <NUM> by means of the boom structure <NUM> of the forestry machine <NUM> and the wood-handling tool <NUM> attached to said boom structure <NUM>.

The start edge of the timber-pile location can be designated <NUM> e.g. by picking a first timber bundle <NUM> from the timber load <NUM> of the load space <NUM> of the forestry machine <NUM> and by transferring and unloading said timber bundle <NUM> on the start edge of the timber-pile location <NUM>. Similarly, the stop edge of the timber-pile location can be designated <NUM> e.g. by picking a second timber bundle <NUM> from the timber load <NUM> of the load space <NUM> of the forestry machine <NUM> and by transferring and unloading said timber bundle <NUM> on the stop edge of the timber-pile location <NUM>. After having designated <NUM>, <NUM> the timber-pile location, it is possible to transfer to the unloading step <NUM>-<NUM> of the timber load. Also correspondingly, if the control system <NUM> in the identifying step identifies <NUM> that the timber-pile location has been designated previously, it is possible to transfer to the unloading step <NUM>-<NUM> of the timber load.

<FIG> shows a top view of an illustration of an unloading situation of a forestry machine according to an embodiment of the invention. In an unloading situation of the load of a forestry machine according to an embodiment of the invention, the forestry machine <NUM> is placing the timber bundle <NUM> in place by means of the boom structure <NUM> and the wood-handling tool <NUM>.

<FIG> shows a perspective view of an illustration of an unloading situation of a forestry machine according to an embodiment of the invention. In an unloading situation of the load of a forestry machine according to an embodiment of the invention, the forestry machine <NUM> is placing the timber bundle <NUM> in place by means of the boom structure <NUM> and the wood-handling tool <NUM>. In <FIG>, the load screen is designated by reference number <NUM>.

<FIG> shows a first top view of an illustration the progress of the unloading of a forestry machine according to an embodiment of the invention. In an unloading situation of the load of a forestry machine according to an embodiment of the invention, the forestry machine <NUM> is placing the timber bundle <NUM> in place by means of the boom structure <NUM> and the wood-handling tool <NUM>. In the unloading step of the load shown in <FIG>, there is still timber load left in the load space of the forestry machine.

<FIG> shows a second top view of an illustration the progress of the unloading of a forestry machine according to an embodiment of the invention. In an unloading situation of the load of a forestry machine according to an embodiment of the invention, the forestry machine <NUM> is placing the last timber bundle <NUM> of the timber load in place by means of the boom structure <NUM> and the wood-handling tool <NUM>. In the unloading step of the load shown in <FIG>, there is no timber load left and the load space of the forestry machine is empty. In <FIG>, the control system of the forestry machine has not yet controlled the wood-handling tool to turn the timber bundle <NUM> straight into a suitable timber-pile location.

<FIG> shows a third top view of an illustration the progress of the unloading of a forestry machine according to an embodiment of the invention. In an unloading situation of the load of a forestry machine according to an embodiment of the invention, the forestry machine <NUM> ready to unload the last timber bundle <NUM> of the timber load in place by means of the boom structure <NUM> and the wood-handling tool <NUM>. In the unloading step of the load shown in <FIG>, there is no timber load left and the load space of the forestry machine is empty. In <FIG>, the control system of the forestry machine has now controlled the wood-handling tool to turn the timber bundle <NUM> straight and is thus ready to unload the timber bundle <NUM> into a suitable timber-pile location.

The control system of the unloading of a timber load according to an arrangement according to the invention facilitates the unloading of a timber load considerably. The control system of the forestry machine according to the arrangement according to the invention automatically assists in controlling and unloading of a timber pile into a designated timber-pile location. In the arrangement according to the invention, the control system of the forestry machine assists the driver in taking the timber bundle always on the accurate distance from the machine and the edge of the timber pile then becomes straight irrespective of the position in which the wood-handling tool grabs the timber bundle in their length direction.

Claim 1:
An arrangement (<NUM>) for controlling the unloading of a forestry machine (<NUM>), in which the forestry machine (<NUM>) comprises a load space (<NUM>) for timber load (<NUM>), a boom structure (<NUM>) and a wood-handling tool (<NUM>) attached to said boom structure, which arrangement (<NUM>) further comprises a control system (<NUM>) and a measuring apparatus (<NUM>) of the forestry machine (<NUM>), wherein
- said measuring apparatus (<NUM>) is arranged to measure the location of the forestry machine (<NUM>) and the rotation angle of the boom structure (<NUM>) and the position of the single boom parts of the boom structure (<NUM>) and the position of the wood-handling tool (<NUM>), wherein
- said control system (<NUM>) is arranged:
- to define and note down the location (<NUM>) of a timber pile characterised in that the control system is further arranged:
- to calculate and note down the position of an edge of the timber pile,
- to control the wood-handling tool (<NUM>) to pick a timber bundle (<NUM>) from the timber load (<NUM>),
- to calculate the distance of an end justified to a load screen (<NUM>) of said timber bundle from the wood-handling tool (<NUM>),
- to calculate an unloading location for said timber bundle into a timber pile even and straight of its one edge in the defined timber pile location (<NUM>), and
- to control and unload said timber bundle in said calculated unloading location in the timber pile.