The invention relates to a harvester head for harvesting, which comprises a frame part, which is arranged with tree processing means for gripping a tree trunk, feeding the tree trunk in a longitudinal direction, delimbing and cutting the tree trunk.

The invention also relates to a harvester head arrangement for harvesting, which comprises a frame part of a harvester head, which is arranged with tree processing means for gripping a tree trunk, feeding the tree trunk in a longitudinal direction, delimbing and cutting the tree trunk. The harvester heads of harvesting machines are typically designed according to the application target to function in an optimal manner in certain use conditions and in a certain type of tree stand to be processed. One of the most typical differentiating factors between harvester heads is their characteristic pro cessing capacity, which can be determined for example according to the max- imum and minimum diameter of the tree, the maximum mass, the number of trunks to be processed simultaneously, the amount of branches of the trunks or corresponding factors. The processing of relatively small trees, such as preliminary thinning trees, is for example not worthwhile doing with a harvester head meant for final felling of large trees, because already moving such an XL- sized harvester head in a dense forest is difficult and time-consuming and consumes an unnecessary amount of energy. Correspondingly the other way around, it is not worthwhile using a harvester head meant for preliminary thinning or other thinning felling performed relatively early in the life span of a tree for the final felling of large trees, because the properties and limits of the har- vester head in question may be reached in many ways, whereby in a worst case scenario the work safety may be endangered due to device failure in a life-threatening manner. In tree processing also productivity is important, i.e. the size of the harvester head needs to be optimised according to the tree and conditions. Additionally environmental aspects, such as the integrity of the re- maining tree stand, damages to the forest floor etc. can better be comprehensively taken into account when using machines of a correct size.

Typically a harvester head manufacturer operating in the field has to offer three or four different sizes of harvester heads having the same functioning principle, whereby a forest machine worker can when necessary change for a harvester head best suited for an on-going or future task. The principle that the tools are selected according to the task can thus be followed. In the field there is a known way of action, where forest machine workers select for each stand marked for cutting the most suitable harvester head and install it in the harvest- ing machine, naturally taking into account the properties of the base machine of the harvesting machine. The trees to be harvested in the stand marked for cutting are usually statistically distributed within a certain range of variation when examined from the point of view of the above-described characteristic processing capacity, whereby such a selection of the correct harvester head can be done relatively simply. An entire harvester head is however a relatively large investment, whereby it would economically be advantageous to somehow be able to reduce the investment needed for harvester heads of different sizes. In the forest industry product branch the competition is very hard and all operations from the forest to the end user must be examined while taking into account also the economy aspect.

It is an object of the invention to provide a harvester head and a harvester head arrangement, which makes possible reducing the investment associated with the changing of the size of the harvester head with technical means, still without having the functionality suffer. It is also an object of the invention to provide an even more versatile arrangement of harvester heads suitable for their purpose, whereby the user can select the tools best suited for the purpose.

The harvester head according to the invention is characterised in that the harvester head can be adapted for processing a different number of and/or differ- ently sized trees by changing at least one module part of the tree processing means, whereby the harvester head's characteristic processing capacity can be changed to correspond to the processing of a different number of and/or differently sized trees, so that the harvester head (1) has a counter surface remaining constant with different settings and diameters, which counter surface functions as the basic surface with different modules and which counter surface is a feeding roller (32), which is rotatingly mounted around an axis (320) in a fixed position in relation to the frame part (10).

The harvester head arrangement according to the invention is on the other hand characterised in that the harvester head arrangement can be adapted for processing differently sized trees by changing at least one module part of the tree processing means comprised in the harvester head, whereby the harvester head's characteristic processing capacity can be changed to correspond to the processing of a different number of and/or differently sized trees, so that the harvester head (1) has a counter surface remaining constant with different settings and diameters, which counter surface functions as the basic surface with different modules and which counter surface is a feeding roller (32), which is rotatingly mounted around an axis (320) in a fixed position in relation to the frame part (10).

With the invention the presented objects can be realised, whereby the techni- cally versatile product entity according to the object can be realised in such a way that the investment remains relatively small in economic terms. In the harvester head according to the invention the tree processing means are formed from module parts, whereby the same technical effect and impact on the functionality of the harvesting machine is obtained by changing a few key compo- nents as by changing the entire harvester head.

According to an advantageous embodiment the frame part of the harvester head is formed so that it functions as a relatively simple attaching base for said different tree processing module parts, whereby each of the tree processing operations can be managed quite independently as an "internal" matter of the tree processing module parts. Thus the frame part could as well be called a frame module, a support module or the like.

When characterising features of the inventions are presented with an "and/or" operator, this means that each alternative can be selected separately or both together. Such as for example when there is a question of number and/or size, then either the number changes or the size changes or both the number and the size change.

Differently sized trees may here for example be a preliminary thinning tree stand, a thinning tree stand and a final felling tree stand typical for the Scandinavian area. In this context it must be noted that forests on different parts of the earth are very different, whereby also the properties of the devices differ from each other remarkably in different markets. However, if we examine mainly forests renewed by planting, the same size distribution is true almost everywhere, only the actual physical measurements and masses change. As a technical feature, the fact that the harvester head can be adapted for processing a different number of and/or differently sized trees also means that the number of trees to be processed at a time can be changed. Typically harvester heads only process one tree at a time, but especially with smaller trees a more efficient result is obtained, when for example three trunks are first collected (and naturally cut by their base) in the grip of the harvester head, whereafter they are simultaneously delimbed and cut into a desired length. In certain cases, such as when collecting energy wood, the delimbing can also be left undone, as long as the cross-sectional dimension of such a bundle containing several trees remains within the limits allowed by the capacity of the harvester head.

The harvester head's characteristic processing capacity depends on many factors, but factors which especially affect it are: mass, diameter, amount of branches, tree type and corresponding factors of the trees to be processed. With regards to mass the situation can be examined from the point of view of the total mass of the tree to be felled, the unit mass, e.g. kg/running metre of trunk, the distribution of the mass to different parts of the tree to be felled and so on. Correspondingly with regards to diameter the base diameter of the tree is generally the most important factor, but the diameter of the branches and possible branching of the tree and other corresponding factors also have an impact. With regards to tree type the main division is made between hard and soft tree types, but also for example the properties of the tree bark have an impact on the capacity and the tools to be selected for the harvester head.

According to an embodiment the greatest aperture, the gripping and/or carry- ing capacity of the harvester head can be changed by changing the gripping module parts. The gripping module parts can for example comprise levers, rollers or other counter surfaces, which determine the location of the tree to be processed in relation to the frame of the harvester head. The gripping capacity and carrying capacity is in addition to just the aperture also affected by other geometrical factors, such as movement paths, location of the tipping centres of the movement paths in relation to each other, location of the tree in relation to different gripping means, dimensions and geometry of the gripping means in the longitudinal direction of the tree etc. The tree to be processed is presented with a counter surface remaining constant with different settings and diame- ters, which counter surface functions as a basic surface with different modules. This counter surface or basic surface thus functions as a sort of work table, against which the tree can be processed. According to an embodiment the feeding properties of the harvester head can be changed by changing the feeding module parts. The feeding properties can change for example with regards to feeding efficiency and its components, strength and speed. When processing heavy trunks, the movement speed of the feeding is usually not as high as when processing lighter trunks, but correspondingly the strength needed from the feeding means is significantly greater. An example of such a change is the changing of the rollers used for feeding into rollers with a larger diameter, when larger trees are processed. Thus the revolution volume or structure of the hydraulic motor or the number of hydraulic motors can simultaneously be selected to be better suited for this purpose. As a second example, when a change is made in order to move to a smaller size, the rollers can be made smaller. Thus with the same feeding and pressure of the hydraulic system, the rotation speed of the hydraulic motor with a smalle revolution volume increases, whereby the tree feeding speed can be increased.

According to an embodiment the delimbing capacity and/or delimbing diameter of the harvester head can be changed by changing the delimbing module parts. This may include for example changing the model, number, geometry or operating principle of the delimbing blades. In some tree types only relatively thin and thus easily processed branches grow in the base part of the tree trunk, but higher up there are branches growing, which almost correspond to the main trunk. In other tree types, however, there are tough branches with a large diameter over the entire length of the trunk, whereby the corresponding delimbing blades must be suitable for this task. According to an embodiment the largest and/or smallest felling or cutting diameter and/or in bundle cutting the cross-sectional surface area of the harvester head can be changed by changing the cutting module parts. For example when using a chainsaw, the blade flange, chain and their casing can be changed for a different length. Another possible change is to exchange the chainsaw for a guillotine-type cutting device. A guillotine is typically used for cutting a tree with a smaller diameter, for which it is a very effective tool.

According to an embodiment the module part or module parts of the tree processing means are arranged to be changeable, so that the module parts comprise a mechanical and/or hydraulic and/or electric connecting interface, whereby by opening the joints of the connecting interface the module part can in its entirety be detached for changing. One impact of this feature is that the change is as simple and quick as possible to make. The quickness also has the advantage that the procedure is pleasant to perform, because it does not waste time, during which the harvesting machine could be doing productive work. The electric and hydraulic connecting interface can be implemented for example by utilising suitable quick connectors.

According to an embodiment the harvester head can be adapted for processing a different number of and/or differently sized trees by changing at least two, three or four of the module parts of the tree processing means. The mod- ule parts can be arranged in several different ways as combinations or pairs, whereby instead of changing one module part, two particular or three particular or four particular module part changes are made. In the same way mutually incompatible module part pairs can be eliminated, such as guillotine cutting and module parts otherwise meant for processing large trees. In the following, the invention will be described in more detail with reference to the appended figures, in which figures

Figure 1 shows a general view of a harvester head,

Figures 2A and 2B show one embodiment of the changing of module parts of the tree processing means,

Figure 3 shows one review of tree sizes

Figure 4 shows one review of the use of mutually compatible modules.

Figure 1 shows a harvester head 1 seen from the direction of a tree T top. The harvester head 1 comprises a frame part 10, the purpose of which is here to function as an attaching and support base for different tree processing module parts. The harvester head 1 is connected as a part of a harvesting machine typically via a tilt arm 1 1 , in the harvester head's 1 end of which tilt arm there is a mechanism 12 for moving the harvester head, which mechanism may for example comprise a tilt device, by means of which the position of the harvester head is controlled between a vertical and a horizontal position. By means of the tilt a tree can for example be controlled to fall in a desired manner in the correct place. Figure 1 also shows feeding rollers belonging to the feeding module parts 3, of which rollers feeding roller 32 is in the embodiment according to Figure 1 rotatingly mounted around an axis 320 in a fixed position in relation to the frame part 10 and a second feeding roller 23 is at the end of a roller lever 22 also rotatingly mounted around an axis 230 and mounted in a turning manner in relation to the roller lever around an axis 231 pointing upward in a perpendicular angle from the image plane in Figure 1. The roller lever 22 turns around its axis 220 in relation to the frame part 10. The figure also shows a gripping lever 21 , by means of which the tree T can be locked to be immobile for example for cutting. Figure 1 also shows an embodiment of the cutting module parts 5 and the delimbing module parts 4.

Figure 2A shows one embodiment, where the gripping 2 module parts and the feeding 3 module parts are changeable, so that larger sized trees T can be processed. For illustrative purposes both alternatives are shown in the same Figure 2A at the same time. Figure 2A shows the roller lever 22 and the feeding roller 23 of the first alternative, and a tree T fitting their processing capacity. Figure 2A also shows the roller lever 22a and the feeding roller 23a of the second alternative, and a tree Ta fitting their processing capacity. In Figure 2A said parts are shown in their "open" extreme position. From the figure can also be seen that certain geometries are more advantageous than other geometries to implement in such a structure based in changeable modules. An example of this may be the feeding roller 32 shown in the figure, which feeding roller is fitted into an angle in relation to the horizontal plane. This angle of the feeding roller (the angle of the rotation axis 320 in relation to the horizontal direction of the figure) may advantageously be about 45 degrees, whereby the geometry of the harvester head can be made especially well applicable for different purposes. The angle can also deviate from this, for example a deviation of ±15 degrees can be usable. Figure 2B shows the structure and representation of Figure 2A, but the roller levers 22, 22a and feeding rollers 23, 23a are shown in a position, which approximately corresponds to the minimal diameter of the tree to be processed.

Figure 3 shows one review of tree sizes as a function of the base diameter and a traditionally implemented size classification of the harvester head. In the middle of the Figure 3 is shown a measuring segment 0, 10, 20, 30, 40, 50, 60, 70, 80, 90 and 100 cm. Below the measuring segment are shown some traditionally implemented harvester head models, which are named with number codes 43, 53, 63, 75 and 83. The optimal processing diameters of trees for these models can be seen from the figure. Above the measuring segment is shown with number code 42 one embodiment of the invention, the optimal op- erating range of which is shown as a diagonally lined bar. Additionally above the measuring segment is shown with number code 62 one embodiment of the invention, the optimal operating range of which is also shown as a diagonally lined bar. When the present invention is applied in such a situation, a harvester head is provided, which can cover the range 42-62 with quite an optimal performance. This can be carried out when the harvester head can be adapted for processing a different number of and/or differently sized trees by changing at least one of the module parts of the tree processing means, whereby the harvester head's characteristic processing capacity can be changed to corre- spond to the processing of a different number of and/or differently sized trees. In this example the diameter variation range 8-30 cm in the area of the bar 42 is seen as one size and the diameter variation range 21-50 in the area of the bar 62 as a second size.

Figure 4 shows a definition of a harvester head arrangement applying the in- vention. Different predefined tree sizes or a classification illustrating the number is shown in the upper line with references A, B, C, D, E, F, G, H. Correspondingly modules with different functions are collected in the left-side column, so that for example the frame modules are 1 , 2, 3, 4, 5 and the gripping modules are k1 , k2 and k3. Compatibility and other matters can then be checked from the intersection between the lines and the columns. In the same way a table like the one presented can be used in an operating system of a harvesting machine, where the currently installed module can be selected from a menu and operating parameters to be used with the module in question can be programmed into the operating system. The harvester head arrangement according to Figure 4 can comprise at least two gripping module parts, by changing the gripping module parts of which the greatest aperture of the harvester head can be changed. The harvester head arrangement can further comprise at least two feeding module parts, by changing the feeding module parts of which the feeding properties of the har- vester head can be changed. The harvester head arrangement can also comprise at least two delimbing module parts, by changing the delimbing module parts of which the delimbing capacity and/or delimbing diameter of the harvester head can be changed. The harvester head arrangement can also comprise at least two cutting module parts, by changing the cutting module parts of which the largest and/or smallest cutting diameter and/or in bundle cutting the cross-sectional surface area of the harvester head can be changed. Advanta- geously in the harvester head arrangement the module part or module parts of the tree processing means are arranged to be changeable, so that the module parts comprise a mechanical and/or hydraulic and/or electric connecting interface, whereby by opening the joints of the connecting interface the module part can in its entirety be detached for changing.

From the table of Figure 4 can also be seen that tree measuring means can be formed to be changeable with the aid of the module parts with regards to their size and/or measuring capacity and/or measuring manner. In the same way the arrangement may also comprise collecting means and debarking means. One presently interesting field is also the collecting of energy wood, whereby the harvester head picks several trunks in its grip before it fells the bundle for processing. The tools associated with keeping this energy wood standing can also be applicable in the way described above.

As is clear to someone skilled in the art, the invention can be applied in many different ways and the above-described examples are not intended to restrict the invention. The features presented in the claims are also meant to be open, so that the protective scope defined by the claims presents a technical minimum definition, whereby a real product may have significantly more features, which are not mentioned in this context.

Reference numbers used in the figures:

1 harvester head

10 frame part

11 tilt arm

12 moving mechanism

2 gripping module parts

21 gripping lever

22 roller lever

220 turning axis of roller lever

23 feeding roller

230 rotating axis of feeding roller

231 turning axis of feeding roller

3 feeding module parts

32 feeding roller

320 rotating axis of feeding roller

4 delimbing module parts

5 cutting module parts