The present invention relates to tree harvesters. More particularly, it relates to an integrated tree harvester and processor and a method for using such a system.

BACKGROUND OF THE INVENTION There are several different known types of harvesters in the prior art.

During tree harvesting and processing operations, there is typically a requirement to cut the tree down to a desired length that is to be as precise as possible.

To measure length, several prior art systems use a measuring wheel that is pressed against the tree trunk and rolls along the tree trunk as it is displaced in the wood handling machine or processor. Thus the wheel measures a distance travelled along the outer surface of the trunk. This method can prove to be inaccurate since it assumes that that the tree trunk is constantly in contact with the measurement system, which is not always the case due to the variable geometry of the tree trunk.

US20100027034 describes method and arrangement for measuring a tree trunk in a wood handling machine. It includes a tree trunk handling device that grips the trunk to be handled, after which one end of the trunk is guided into a measuring carriage. The trunk arranged in the measuring carriage is subjected to one or more observation measures by observation measurement devices provided in the measuring carriage, including gripping means for measuring a diameter of the trunk and a counter surface to help carry out a length measurement with a measurement beam. However, the measurement beam in the above-described system can be subject to interference from branches on the tree trunk and therefore not be able to carry out length measurements of the tree trunk. Moreover, the above-described measuring carriage can be subject to malfunctions of the gripping means and not be able to properly receive trunks exceeding a certain base diameter or shape.

Consequently, there is presently a need for an integrated tree harvester and processor system that addresses at least one of the above-described drawbacks. SUMMARY OF THE INVENTION

Accordingly, it is an object of the present invention to an integrated tree harvester and processor system to overcome at least one drawback of the prior art.

According to the present invention, there is provided a tree harvester and processor system comprising:

-a movable base frame;

-an upper frame rotatable with respect to the base frame;

-a tree trunk cutting, handling and processing unit;

-a boom system for displacing and positioning the tree trunk cutting, handling and processing unit with respect to the rotatable upper frame;

-a support surface positioned on a support structure projecting away from the rotatable upper frame for receiving a base of a tree trunk being handled by the tree trunk cutting, handling and processing unit;

-a plurality of sensors positioned in components of the boom system and generating data indicative of positions of the components;

-a processing unit for processing the data indicative of positions of the boom components, calculating a distance between the tree trunk cutting, handling and processing unit and the support surface, and enabling the system to cut the tree trunk according to a predetermined length based on the calculated distance.

According to the present invention, there is also provided a tree length measurement kit adapted for installation on and use with a tree harvester and processor system, said system comprising:

-a movable base frame;

-an upper frame rotatable with respect to the base frame;

-a tree trunk cutting, handling and processing unit; and

-a boom system for displacing and positioning the tree trunk cutting, handling and processing unit with respect to the rotatable upper frame;

said tree length measurement kit comprising:

-a support surface positioned on a support structure installable on the rotatable upper frame, said support surface receiving a base of a tree trunk being handled by the tree trunk cutting, handling and processing unit;

-a plurality of sensors positionable in components of the boom system and generating data indicative of positions of the components;

-a processing unit for processing the data indicative of positions of the boom components, calculating a distance between the tree trunk cutting, handling and processing unit and the support surface, and enabling the system to cut the tree trunk according to a predetermined length based on the calculated distance.

According to the present invention, there is also provided a method for measuring a length of a tree trunk, comprising the steps of:

a) providing a tree harvester and processor system comprising:

-a movable base frame;

-an upper frame rotatable with respect to the base frame;

-a tree trunk cutting, handling and processing unit; -a boom system for displacing and positioning the tree trunk cutting, handling and processing unit with respect to the rotatable upper frame; -a support surface positioned on a support structure projecting away from the rotatable upper frame;

-a plurality of sensors positioned in components of the boom system and generating data indicative of positions of the components;

b) positioning a base of a tree trunk on the support surface with the cutting, handling and processing unit;

c) processing the data indicative of positions of the boom components, and calculating a distance between the tree trunk cutting, handling and processing unit and the support surface; and

d) enabling the system to cut the tree trunk according to a predetermined length based on the calculated distance.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other objects and advantages of the invention will become apparent upon reading the detailed description and upon referring to the drawings in which:

Figure 1 is a side view of a system according to a preferred embodiment of the present invention.

Figure 2 is a side view of a system according to another preferred embodiment of the present invention.

Figure 3 a side view of a system according to another preferred embodiment of the present invention. Figures 4A and 4B are detailed side views of a support surface of the system shown in Figure 2.

PREFERRED EMBODIMENTS OF THE PRESENT INVENTION

Figure 1 illustrates different aspects of a preferred embodiment of the present invention.

As shown in Figure 1 , there is provided tree harvester and processor system 10 comprising a movable base frame 12, an upper frame 14 rotatable with respect to the base frame 12 and a tree trunk cutting, handling and processing unit 1 6. A boom system 17,18 displaces and positions the tree trunk cutting, handling and processing unit 1 6 with respect to the rotatable upper frame 14. A support surface 20 is positioned on a support structure 22 projecting away from the rotatable upper frame 14 for receiving a base of a tree trunk 24 being handled by the tree trunk cutting, handling and processing unit 1 6. A plurality of sensors 30 positioned in components of the boom system 18 generate data indicative of positions of the components. A processing unit processes the data indicative of positions of the boom components, for calculating a distance between the tree trunk cutting, handling and processing unit 1 6 and the support surface 20, and enabling the cutting, handling and processing unit 1 6 to cut the tree trunk 24 according to a predetermined length based on the calculated distance.

The plurality of sensors 30, preferably three sensors positioned at the main articulation points of the boom system, or other sensors known in the art, either alone or in combination with other sensors, form a sensor system that can interface with the processing unit. These sensors are operable to transmit boom component position signal(s) to the processing unit. These signals are indicative of position(s) of the various components of the boom system and/or the actuator(s) displacing the boom components. The processing unit receives these position signals and responsively determines (via geometric calculations for example) a position of the cutting, handling and processing unit, with respect to the upper structure or the support surface. It should be understood that different or additional position indicating mechanisms or sensors known in the art may be used to indicate the position of the tree harvester head structure including the tree cutting, handling and processing unit and to communicate indicative signals to the processing unit.

The system according to the present invention ensures a substantially constant length cut of trees from one cutting operation to another.

Preferably, the selection of the length for cutting of the tree may be done manually or automatically based on the calculations made by the processing unit.

By using the integrated system, which can cut trees to a constant desired length, and subsequently process the tree with the processing unit, a total number of cutting and processing units is reduced, compared to several prior art operations and systems that require multiple non-integrated systems.

By positioning the support surface on the upper rotatable frame, the working area where the trees are cut and processed is significant, since when an initial area where trees are processed becomes cluttered with processed trees, the upper frame can rotate towards another direction and continue processing of the trees. This can increase the overall speed of processing of a large number of trees within a specific area. Avoiding the use of a gripping system when placing the tree against the support surface, as disclosed in the prior art, also increases the speed of processing of the trees since a gripping sequence is avoided.

As mentioned in the Summary of the Invention section, the system according to the present invention can be installed as an upgrade kit to an existing harvestor/processor system. According to the present invention, there is provided a method for measuring a length of a tree trunk, to which a number of optional steps may be added. The method comprises the steps of :

a) providing a tree harvester and processor system comprising:

-a movable base frame;

-an upper frame rotatable with respect to the base frame;

-a tree trunk cutting, handling and processing unit;

-a boom system for displacing and positioning the tree trunk cutting, handling and processing unit with respect to the rotatable upper frame;

-a support surface positioned on a support structure projecting away from the rotatable upper frame;

-a plurality of sensors positioned in components of the boom system and generating data indicative of positions of the components;

b) positioning a base of a tree trunk on the support surface with the cutting, handling and processing unit;

c) processing the data indicative of positions of the boom components, and calculating a distance between the tree trunk cutting, handling and processing unit and the support surface; and

d) enabling the cutting, handling and processing unit to cut the tree trunk according to a predetermined length based on the calculated distance.

Preferably, the cutting operation in step d) may be accomplished in a manual or automatically programmed mode.

Figures 2 and 3 show a system according to another preferred embodiment of the present invention. The tree harvester and processor system 10 comprises a movable base frame 101 , an upper frame 104 rotatable with respect to the base frame 101 and a tree trunk cutting, handling and processing unit 102. A boom system 105,106 displaces and positions the tree trunk cutting, handling and processing unit 102 with respect to the rotatable upper frame 104. A support surface 103 is positioned on a support structure 22 projecting away from the rotatable upper frame 104 for receiving a base of a tree trunk 1 13 being handled by the tree trunk cutting, handling and processing unit 102. A plurality of sensors 30 positioned in components of the boom system 105,106 generate data indicative of positions of the components. A processing unit processes the data indicative of positions of the boom components, for calculating a distance between the tree trunk cutting, handling and processing unit 102 and the support surface 103, and enabling the system 10 to cut the tree trunk 1 13 according to a predetermined length based on the calculated distance.

Preferably, the tree trunk cutting, handling and processing unit 102 comprises a slasher unit 109, feed rollers 1 1 1 , and grapple tongs 1 12. Tree accumulators 1 10 are also provided to hold several trees at the same time. Pivoting elements 108 allow the tree trunk cutting, handling and processing unit 102 to pivot about different axes.

Preferably, as shown in Figures 4A and 4B, the support structure 22 can adjustably position the support surface 103 to accommodate positioning of the extremity of the tree. Preferably, a cutting sequence will comprise the following steps:

a) the tree trunk cutting, handling and processing unit 102 positions it self vertically to cut the tree at its base;

b) the slasher unit 109 cuts the tree at its base;

c) the tree trunk cutting, handling and processing unit 102 repositions the tree horizontally;

d) the boom elements 105,106 reposition the tree trunk cutting, handling and processing unit 102 such that it is oriented towards the support surface 103; e) the feed rollers 1 1 1 displace the tree towards the support surface 103, while the grapple tongs 1 12 act as knives and remove branches; f) when the extremity of the tree 1 13 reaches the support surface 103, the slasher unit 103 cuts the tree portion to the predetermined length;

g) steps e) and f) are repeated until all of the tree is cut.

Although preferred embodiments of the present invention have been described in detailed herein and illustrated in the accompanying drawings, it is to be understood that the invention is not limited to these precise embodiments and that various changes and modifications may be effected therein without departing from the scope of the present invention.