FIELD OF THE INVENTION

The present invention relates to a spike arrangement and more particularly to a spike arrangement according to preamble of claim 1.

The present invention further relates to a feed roller and more particularly to a feed roller according to preamble of claim 11.

The present invention further relates to a forest harvester head and more particularly to a feed roller according to preamble of claim 15.

BACKGROUND OF THE INVENTION

In the prior art spike plates of a feed roller for a forest harvester having one longitudinal spike. The spike plates and spikes are arranged to form one row along a circumference of a feed roller as shown in figure 11.

One of the problems associated with the prior art is that the wood material such as bark stuck between the spikes of a feed roller head when forest harvester head is used for moving trees. Thus, feed rollers are not able to grasp trees and the user of forest harvester must stop using the forest harvester and remove the wood material from the feed roller.

BRIEF DESCRIPTION OF THE INVENTION

An object of the present invention is to provide a spike arrangement, a feed roller and a forest harvester head so as to solve or at least alleviate the prior art disadvantages.

The objects of the invention are achieved by a feed roller which is characterized by what is stated in the independent claim 1.

The objects of the invention are further achieved by a spike arrangement which is characterized by what is stated in the independent claim 11.

The objects of the invention are further achieved by a spike arrangement which is characterized by what is stated in the independent claim 15.

The preferred embodiments of the invention are disclosed in the dependent claims.

The invention is based on the idea of providing a spike arrangement for a feed roller of forest harvester head. The spike arrangement comprises a first end and a second end at a distance from the first end, the spike arrangement comprises a first side edge extending in a direction between the first end and the second end of the spike arrangement, the spike arrangement comprises a second side edge at a distance from the first side edge of the spike arrangement, the second side edge of the spike arrangement extending in a direction between the first end and the second end of the spike arrangement, the spike arrangement comprises one or more first stopper surfaces and one or more first spikes provided between the first side edge and the second side edge of the spike arrangement, the one or more first stopper surfaces are provided in a connection with the second side edge of the spike arrangement, the spike arrangement comprises one or more second stopper surfaces and one or more second spikes provided between the first side edge of the spike arrangement and the second side edge of the spike arrangement, the one or more second stopper surfaces are provided in connection with the first side edge of the spike arrangement.

In one embodiment of the present invention, the spike arrangement further comprises one or more transversal stopper surfaces provided between the one or more first spikes and the one or more second spikes, and the one or more transversal stopper surfaces extending in a direction between the first side edge of the spike arrangement and the second side edge of the spike arrangement.

In another embodiment, the spike arrangement comprises one or more transversal stopper surfaces provided between the one or more first spikes and the one or more second spikes, the one or more transversal stopper surfaces extending in a direction between the first side edge of the spike arrangement and the second side edge of the spike arrangement, and one or more transversal stopper surfaces are provided in connection with the one or more first stopper surfaces and in connection with the one or more second stopper surfaces.

The one or more transversal stopper surfaces further prevents the spikes to penetrate to far inside a tree and thus , the tree is not compromised during operating the forest harvester head.

In one embodiment of the present invention, the one or more first spikes comprise a first spike base between one or more first stopper surfaces and the first side edge of the spike arrangement, the one or more first spikes further comprise a first spike top at distance from the first spike base, the one or more first spikes extending from the first spike base to the first spike top, and the one or more first spikes tapering towards the first spike top. The one or more second spikes comprise a second spike base between one or more second stopper surfaces and the second side edge of the spike arrangement, the one or more second spikes further comprise a second spike top at distance from the second spike base, the one or more second spikes extending from the second spike base to the second spike top, and the one or more second spikes tapering towards the first spike top.

The tapering of the one or more first spikes and the one or more second spikes decrease force which is need to grasp to tree.

In one embodiment of the present invention, the spike arrangement having a spike arrangement centre line extending in a direction between the first end of the spike arrangement and the second end of the spike arrangement, and the first side edge of the spike arrangement and the second side edge of the spike arrangement extending in a direction parallel to the spike arrangement centre line. This enables efficiently manufacture the spike arrangement.

In one embodiment of the present invention, the spike arrangement having a spike arrangement centre line extending in a direction between the first end of the spike arrangement and the second end of the spike arrangement, and the one or more first spikes are provided one side of the spike arrangement centre line and the one or more second spikes are provided other side of the spike arrangement centre line than the one or more first spikes.

This further reduces risk that wood material stuck in the feed roller.

In another embodiment, the spike arrangement having a spike arrangement centre line extending in a direction between the first end of the spike arrangement and the second end of the spike arrangement, the one or more first spikes are provided one side of the spike arrangement centre line and the one or more second spikes are provided other side of the spike arrangement centre line than the one or more first spikes, the one or more first spikes and the one or more second spikes are arranged to form a row of spikes extending in a direction between the first end of the spike arrangement and the second end of the spike arrangement, and every other spike in the row of spikes being the one or more first spikes.

This further reduces risk that wood material stuck in the feed roller.

In one embodiment of the present invention, the spike arrangement is provided to a spike plate, and the spike plate further extending from the first side edge and the second side edge in direction away from the first spike top.

This enables a construction of a feed roller such that the spike plates may be fixedly fixed to feed roller body and thus, machining of the parts of feed roller is minimized.

In an alternative embodiment, the spike arrangement is machined to a steel plate, the spike arrangement extending from the first side edge and the second side edge in direction away from the first spike top.

In an another alternative embodiment, the spike arrangement is machined to a steel plate.

In a yet another embodiment, the spike arrangement is provided on a feed roller of forest harvester head.

This enables a simple construction of a feed roller.

In a yet another embodiment, the spike arrangement is provided on a feed roller of forest harvester.

In one embodiment, the spike arrangement is provided on a feed roller comprising a tubular body.

This prevents loose wood material from reaching a feed roller motor. This is especially advantageous for feed rollers having a small diameter.

In one embodiment, the spike arrangement is provided on a feed roller and the spike arrangement is arranged to taper in the direction of the rotation axis.

This increases a pressing force between a log and the feed roller. This is especially advantageous for thick logs.

In one embodiment, the feed roller body comprises the motor mounting plate. The feed roller motor is arranged to mounted to the motor mounting plate so that the feed roller motor extending from the motor mounting plate towards the first end of the spike arrangement or towards the plurality of the spike arrangements.

This further increases a pressing force between a log and the feed roller. This is especially advantageous for thick logs. In one embodiment, the spike arrangement comprises the one or more extended first spikes and the one or more extended second arranged to extend from the second end of the spike arrangement towards the first end of the spike arrangement.

This increases a pressing force between logs and the feed roller. This is especially advantageous for thick logs. Furthermore, the spike arrangements are simple to manufacture.

In one embodiment, a plurality of the spike arrangements is provided to the feed roller. The feed roller body comprises the motor mounting plate and one or more spike arrangement support plates. The one or more spike arrangement support plates arranged to support the plurality of the spike arrangements.

This enables increasing length of the feed roller without comprising durability of the feed roller.

In one embodiment of the present invention, the one or more first stopper surfaces extending from the first side edge of the spike arrangement to a direction towards the second side edge of the spike arrangement.

In an alternative embodiment, the one or more first stopper surfaces extending from the first side edge of the spike arrangement to a direction towards the second side edge of the spike arrangement and the one or more second stopper surfaces extending from the second side edge to a direction towards the first side edge of the spike arrangement.

In another alternative embodiment, the one or more first stopper surfaces extending from the first side edge of the spike arrangement to a direction towards the one or more first spikes.

In a yet another alternative embodiment, the one or more first stopper surfaces extending from the first side edge of the spike arrangement to a direction towards the one or more first spikes and the one or more second stopper surfaces extending from the second side edge to a direction towards one or more second spikes.

The one or more first and second stopper surfaces further prevents the spikes to penetrate to far inside a tree and thus , the tree is not compromised during operating the forest harvester head.

In one embodiment of the present invention, the spike arrangement comprises an installation recess provided to the second end of the spike arrangement.

In an alternative embodiment, the spike arrangement comprises an installation recess provided to the second end of the spike arrangement, the installation recess comprises a first support surface and a second support surface, the second support surface extending transverse relative to the second support surface.

In another alternative embodiment, the spike arrangement comprises an installation recess provided to the second end of the spike arrangement, the installation recess comprises a first support surface and a second support surface, the first support surface extending transverse relative to the one or more first stopper surfaces, and the second support surface extending transverse relative to the first support surface.

In a yet another alternative embodiment, the spike arrangement comprises an installation recess provided to the second end of the spike arrangement, the installation recess comprises a first support surface and a second support surface, the first support surface extending perpendicular to the one or more first stopper surfaces, and the second support surface extending perpendicular to the first support surface.

The installation recess comprising the first support surface and a second support surface provides a support during installation the spike arrangement. The first support surface and the second support surface further ease keeping a steel plate in desired position during machining the one or more first spikes and the one or more first spikes to the steel plate.

In one embodiment of the present invention, the spike arrangement comprises a bottom surface at a distance from the one or more first stopper surfaces, the spike arrangement extending between the bottom surface and the first and the second spike top, the one or more first spikes having a first spike centre line extending in a direction between the first spike base and the first spike top, the one or more second spikes having a second spike centre line extending in a direction between the second spike base and the second spike top, the first spike centre line being perpendicular to the first spike base, and the second spike centre line being perpendicular to the second spike base.

This means that the spike arrangement may extend from a circumference of a feed roller towards the rotation axis of the feed roller and thus, the spike plate may be fixed reliably to a body of a feed roller.

In one embodiment of the present invention, the one or more first spikes comprises a first spike end and a second spike end, the one or more first spikes further comprises a first spike side surface and a second spike side surface; the first spike side surface and the second spike side surface extending between the first spike top and the first spike base; the first spike top, the first spike base, the first spike side surface and the second spike side surface extending between the first spike end and the second spike end, the one or more first spikes further comprises a first vertical stopper surface provided to the first spike end and a second vertical stopper surface provided to the second spike end; and the one or more second spikes comprises a third spike end and a fourth spike end, the one or more second spikes further comprises a third spike side surface and a fourth spike side surface; the third spike side surface and the fourth spike side surface extending between the second spike top and the second spike base; the second spike top, the second spike base the third spike side surface and the fourth spike side surface extending between the third spike end and the fourth spike end, the one or more second spikes further comprises a third vertical stopper surface provided to the third spike end and a fourth vertical stopper surface provided to the fourth spike end.

Vertical stopper surfaces prevent threes moving on feed roller in direction parallel to a rotation axis.

In one embodiment, the spike arrangement is made of steel.

In an alternative embodiment, the spike arrangement is made of steel plate.

In a yet alternative embodiment, the spike arrangement is machined of steel plate.

In other words, a steel plate cut into a final shape and size of the spike arrangement.

A steel plate cut into a final shape and size of the spike arrangement provides an efficient way to manufacture the spike arrangements.

The present invention further relates to feed roller for a forest harvester head. The feed roller comprises a feed roller body arranged to be rotated around a rotation axis and arranged to be operatively connected to a harvester head, a plurality of first spike arrangements provided to the feed roller body at the first circumference from the rotation axis, the plurality of first spike arrangements is arranged to form a first circular row of spike arrangements around the rotation axis at a distance from the rotation axis, a plurality of second spike arrangements provided to the feed roller body at the first circumference from the rotation axis, the plurality of second spike arrangements is arranged to form a second circular row of spike arrangements at a distance from the rotation axis; the first spike arrangements are provided at a first distance from the adjacent second spike arrangements along the first circumference .

In one embodiment of the present invention, the feed roller body comprises a first side and a second side, the first side and the second side of the feed roller body being transverse in relative to the rotation axis, the second side of the feed roller body being at distance from the first side of the feed roller body, the plurality of first spike arrangements protruding from the first side of the feed roller body in a direction away from the second side of the feed roller body and the plurality of second spike arrangements protruding from the second side of the feed roller body in a direction away from the first side of the feed roller body.

In an alternative embodiment, the feed roller body comprises a first side and a second side, the first side and the second side of the feed roller body being transverse in relative to the rotation axis, the second side of the feed roller body being at distance from the first side of the feed roller body, the plurality of first spike arrangements protruding from the first side of the feed roller body in a direction away from the second side of the feed roller body and the plurality of second spike arrangements protruding from the second side of the feed roller body in a direction away from the first side of the feed roller body, the plurality of first spike arrangements and the feed roller body forming a plurality of first recesses, and the plurality of second spike arrangements and the feed roller body forming a plurality of second recesses.

These embodiments provide a route away from feed roller such material does no stuck to the feed roller.

The material being wood material.

In one embodiment of the present invention, the feed roller body comprises an outer surface between the first side and the second side of the feed roller body, the outer surface being at a distance from the rotation axis, the plurality of first spike arrangements protruding from the outer surface of the feed roller body in a direction away from the rotation axis, and the plurality of second spike arrangements protruding from the outer surface of the feed roller body in a direction away from the rotation axis.

In an alternative embodiment, the feed roller body comprises an outer surface between the first side and the second side of the feed roller body, the outer surface being at a distance from the rotation axis, the feed roller body comprises a plurality of first holding recesses arranged to receive the plurality of first spike arrangements and a plurality of second holding recesses arranged to receive the plurality of second spike arrangements, the plurality of first spike arrangements protruding from the outer surface of the feed roller body in a direction away from the rotation axis, and the plurality of second spike arrangements protruding from the outer surface of the feed roller body) in a direction away from the rotation axis.

These embodiments enable moving the tree in the forest harvester head equally in two directions.

In one embodiment, the first spike arrangements of the plurality of first spike arrangements comprises any above disclosed embodiment of a spike arrangement and the plurality of the second spike arrangements comprises any above disclosed embodiment of a spike arrangement.

In one embodiment, the feed roller is made of steel.

In one embodiment, the plurality of first spike arrangements and the plurality of second spike arrangements are fixedly fixed to the feed roller body.

In one embodiment, the plurality of first spike arrangements and the plurality of second spike arrangements are welded to the feed roller body.

In an alternative embodiment, the plurality of first spike arrangements and the plurality of second spike and the feed roller body are provided with three dimensional printing.

In an alternative embodiment, the plurality of first spike arrangements and the plurality of second spike and the feed roller body are made of polymer with a three dimensional printing.

In an alternative embodiment, the plurality of first spike arrangements and the plurality of second spike and the feed roller body are made of polyaramid with a three dimensional printing.

The three-dimensional printing is an efficient way to produce feed rollers. In one embodiment, the plurality of first spike arrangements 10a is provided on the feed roller body and arranged to extend on the feed roller body a first overlapping distance. The plurality of second spike arrangements is provided on the feed roller body and arranged to extend on the feed roller body a second overlapping distance, the first overlapping distance is greater than the second overlapping distance.

This prevents bark from sticking to the feed roller as the spike arrangements cut the bark into pieces,

The present invention further relates to a forest harvester head. The forest harvester head comprises comprising a feed roller body arranged to rotate around a rotation axis and the feed roller body being operatively connected to a feed roller motor, a plurality of first spike arrangements provided to the feed roller body at the first circumference from the rotation axis, the plurality of first spike arrangements is arranged to form a first circular row of spike arrangements around the rotation axis at a distance from the rotation axis, a plurality of second spike arrangements provided to the feed roller body at the first circumference from the rotation axis, the plurality of second spike arrangements is arranged to form a second circular row of spike arrangements at a distance from the rotation axis; the first spike arrangements are provided at a first distance along the first circumference from the adjacent second spike arrangements.

In one embodiment, the forest harvester head comprises any above disclosed embodiment of a feed roller.

An advantage of the invention that it enables reliably operate forester harvester head for moving trees. Furthermore, trees may be equal reliably moved in two directions. Furthermore, the invention provides feed roller which is easy to manufacture.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is described in detail by means of specific embodiments with reference to the enclosed drawings, in which

Figure 1 shows schematically a 3-D view of a spike arrangement according to one embodiment of the present invention;

Figure 2 shows schematically a top view of the spike arrangement of figure 1;

Figure 3 shows schematically a first side view of the spike arrangement of figure 1;

Figure 4 shows schematically a second side view of the spike arrangement of figure 1;

Figure 5 shows schematically a 3-D view of a feed roller according to one embodiment of the present invention;

Figure 6 shows schematically a top view of the feed roller of the figure 5;

Figure 7 shows schematically a detail of the figure 6;

Figure 8 shows schematically a side view of the feed roller of the figure 5;

Figure 9 shows schematically a detail of the figure 8;

Figure 10 shows schematically a forest harvester head according to one embodiment of the present invention; and

Figure 11 shows schematically a 3-D view of a feed roller according to prior art;

Figure 12 shows schematically a top view of a feed roller according to one embodiment of the present invention;

Figure 13 shows schematically a detail of the figure 12;

Figure 14 shows schematically a cross section view of a spike arrangement according to one embodiment of the present invention;

Figure 15 shows schematically a cross section view of a spike arrangement according to one embodiment of the present invention;

Figure 16 shows schematically a top view of a spike arrangement according to one embodiment of the present invention;

Figure 17 shows schematically a detail of a top view of a spike arrangement according to one embodiment of the present invention;

DETAILED DESCRIPTION OF THE INVENTION

Figures 1 to 4 show one embodiment of a spike arrangement 10 for a feed roller 500 of forest harvester head 600. The spike arrangement 10 comprises a first end 102 and a second end 103 at a distance from the first end 102. The spike arrangement 10 comprises a first side edge 100 extending between the first end 102 and the second end 103 of the spike arrangement 10. The spike arrangement 10 comprises a second side edge 101 at a distance from the first side edge 100 of the spike arrangement 10 The second side edge 101 of the spike arrangement 10 extending between the first end 102 and the second end 103 of the spike arrangement 10. The spike arrangement 10 comprises one or more first stopper surfaces 106 and one or more first spikes 105 provided between the first side edge

100 and the second side edge 101 of the spike arrangement 10. The one or more first stopper surfaces 106 are provided in a connection with the second side edge

101 of the spike arrangement 10. The spike arrangement 10 comprises one or more second stopper surfaces 107 and one or more second spikes 20 provided between the first side edge 100 of the spike arrangement 10 and the second side edge 101 of the spike arrangement 10. The one or more second stopper surfaces 107 are provided in connection with the first side edge 100 of the spike arrangement 10.

In one embodiment, the spike arrangement 10 having a spike arrangement centre line CL extending in a direction between the first end 102 of the spike arrangement 10 and the second end 103 of the spike arrangement 10, and the first side edge 100 of the spike arrangement 10 and the second side edge 101 of the spike arrangement 10 extending in a direction parallel to the spike arrangement centre line CL.

In the context of this application the first side edge 100 of the spike arrangement 10 extending along edges of the first spike base 112 which further from the spike arrangement centre line CL. In the context of this application the second side edge 101 of the spike arrangement 10 extending along edges of the second spike base 212 which are further from the spike arrangement centre line CL.

In one embodiment the spike arrangement comprises one or more transversal stopper surfaces 108 provided between the one or more first spikes 105 and the one or more second spikes 205, the one or more transversal stopper surfaces 108 extending in a direction between the first side edge 100 of the spike arrangement 10 and the second side edge 101 of the spike arrangement 10, and one or more transversal stopper surfaces 108 are provided in connection with the one or more first stopper surfaces 106 and in connection with the one or more second stopper surfaces 107.

In other words, there is a gap between the adjacent one or more first spikes 105 and the one or more second spikes 205.

In one embodiment the gap between the adjacent one or more first spikes 105 and the one or more second spikes 205 being between 5 mm and 15 mm

In one embodiment, the one or more first spikes 105 comprise a first spike base 112 between one or more first stopper surfaces 106 and the first side edge 100 of the spike arrangement 10, the one or more first spikes 105 further comprise a first spike top 113 at distance from the first spike base 112, the one or more first spikes 105 extending from the first spike base 112 to the first spike top 113, and the one or more first spikes 105 tapering towards the first spike top 113. The one or more second spikes 205 comprise a second spike base 212 between one or more second stopper surfaces 107 and the second side edge 101 of the spike arrangement 10. The one or more second spikes 205 further comprise a second spike top 213 at distance from the second spike base 212, the one or more second spikes 205 extending from the second spike base 212 to the second spike top 213, and the one or more second spikes 205 tapering towards the second spike top 213.

In one embodiment, the one or more first spikes 105 are provided one side of the spike arrangement centre line CL and the one or more second spikes 205 are provided other side of the spike arrangement centre line CL than the one or more first spikes 105, the one or more first spikes 105 and the one or more second spikes 205 are arranged to form a row of spikes extending in a direction between the first end 102 of the spike arrangement 10 and the second end 103 of the spike arrangement 10, and every other spike in the row of spikes being the one or more first spikes 105. In one embodiment, the one or more first spikes 105 having a first spike length LI in a direction between the first end 102 of the spike arrangement 10 and the second end 103 of the spike arrangement 10. The first spike length LI being between 10 mm and 50 mm.

In one embodiment, the one or more second spikes 205 having a first spike length L2 in a direction between the first end 102 of the spike arrangement 10 and the second end 103 of the spike arrangement 10. The second spike length L2 being between 10 mm and 50 mm.

In one embodiment, the second spike length L2 being equal to the first spike length LI.

In one embodiment, the one or more first spikes 105 are arranged closer to the first side edge 100 than the one or more second spikes 205 and the one or more second spikes 205 are arranged closer to the second side edge 101 than the one or more second spikes 205.

In one embodiment, the first spike top 113 of the one or more first spikes 105 are arrange to form a first line of the spikes, the second spike top 213 of the one or more second spikes 205 are arrange to form a second line of the spikes the first line of the spikes and the second line of spikes are arranged to extend parallel to each other.

In one embodiment, the first line of the spikes is arranged closer to the to the first side edge 100 than the second line of spikes and the second line of the spikes is arranged closer to the to the second side edge 101 than the first line of spikes.

In one embodiment, the spike arrangement 10 comprises a third line of spikes (not shown in figures). This means that the spike arrangement 10 comprises one or more third spikes provided between the one or more first spikes and the one or more second spikes. The first line of the spikes is arranged closer to the to the first side edge 100 than the third line of spikes and the second line of the spikes is arranged closer to the to the second side edge 101 than the third line of spikes.

In one embodiment, the spike arrangement 10 is provided to a spike plate 300, and the spike plate 300 further extending from the first side edge 100 and the second side edge 101 in direction away from the first spike top 113.

In an alternative embodiment, the spike arrangement 10 is provided on a feed roller 500 of forest harvester head 600. A feed roller is shown in figure 5 and an harvester head 600 is shown in figure 10.

In one embodiment, the one or more first stopper surfaces 106 extending from the first side edge 100 of the spike arrangement 10 to a direction towards the second side edge 101 of the spike arrangement 10 and the one or more second stopper surfaces 107 extending from the second side edge 101 to a direction towards the first side edge 100 of the spike arrangement 10.

In one embodiment, the one or more first stopper surfaces 106 being parallel to the one or more second stopper surfaces 107.

In one embodiment, the one or more first stopper surfaces 106 extending from the first side edge 100 of the spike arrangement 10 to a direction towards the one or more first spikes 105 and the one or more second stopper surfaces 107 extending from the second side edge 101 to a direction towards one or more second spikes 205.

In one embodiment, the spike arrangement 10 comprises an installation recess 109 provided to the second end 103 of the spike arrangement 10, the installation recess 109 comprises a first support surface 110 and a second support surface 111, the first support surface 110 extending transverse relative to the one or more first stopper surfaces 106, and the second support surface 110 extending transverse relative to the second support surface 111.

In figures 3 and 4 is shown a first side view and a second side view of the spike arrangement 10.

In one embodiment, the spike arrangement 10 comprises a bottom surface 301 at a distance from the one or more first stopper surfaces 106, the spike arrangement 10 extending between the bottom surface 301 and the first and the second spike top 113, 213. The one or more first spikes 105 having a first spike centre line F extending in a direction between the first spike base 112 and the first spike top 113, the one or more second spikes 106 having a second spike centre line G extending in a direction between the second spike base 112 and the second spike top 113, the first spike centre line F being perpendicular to the bottom surface 301, and the second spike centre line G being perpendicular to the bottom surface 301.

In one embodiment, the one or more first spikes 105 comprises a first spike end 150 and a second spike end 151, the one or more first spikes 105 further comprises a first spike side surface 114 and a second spike side surface 115. The first spike side surface 114 and the second spike side surface 115 extending between the first spike top 113 and the first spike base 112. The first spike top 113, the first spike base 112, the first spike side surface 114 and the second spike side surface 115 extending between the first spike end 150 and the second spike end 151, the one or more first spikes 105 further comprises a first vertical stopper surface 120 provided to the first spike end 150 and a second vertical stopper surface 121 provided to the second spike end 151. The one or more second spikes 205 comprises a third spike end 250 and a fourth spike end 251, the one or more second spikes 205 further comprises a third spike side surface 214 and a fourth spike side surface 215. The third spike side surface 214 and the fourth spike side surface 215 extending between the second spike top 213 and the second spike base 212. The second spike top 213, the second spike base 212, the third spike side surface 214 and the fourth spike side surface 215 extending between the third spike end 250 and the fourth spike end 251, the one or more second spikes 205 further comprises a third vertical stopper surface 220 provided to the third spike end 250 and a fourth vertical stopper surface 221 provided to the fourth spike end 251.

In one embodiment, the one or more first spikes 105 being longitudinal in a direction parallel to a spike arrangement centre line C and the one or more second spikes 105 being longitudinal in a direction parallel to a spike arrangement centre line CL.

In one embodiment, the first spike top 113 and the second spike top 213 being blunt.

In one embodiment, the spike arrangement 10 comprises at the first spike top 113 one or more bevels, or a flat surface, or a rounding.

In one embodiment, the spike arrangement 10 comprises at the second spike top 213 one or more bevels, or a flat surface, or a rounding.

In one embodiment, the one or more first spikes 105 having a first spike height Hl in a direction between the first spike top 113 and the first spike base 112, and the first spike height Hl being between 5 mm and 30 mm.

In one embodiment, the one or more second spikes 205 having a second spike height H2 in a direction between the second spike top 213 and the second spike base 112, and the second spike height H2 being between 5 mm and 30 mm.

In one embodiment, the first spike height Hl being equal to the second spike height H2.

In one embodiment, the first spike side surface 114 and the second spike side surface 115 are arranged to provide tapering of the one or more first spikes 105.

In other words, the one or more first spikes 105 having a first spike angle A between the first spike base 112 and the first spike side surface 114 or between the first spike base 112 and a portion of the first spike side surface 114, the one or more first spikes 105 having a second spike angle B between the first spike base 112 and the second spike side surface 115 or between the first spike base 112 and a portion of the second spike side surface 115, and the first spike angle A and the second spike angle B being between 30 and 60 degrees.

In one embodiment, the third spike side surface 214 and the fourth spike side surface 215 provide tapering of the one or more second spikes 205.

In other words, the one or more second spikes 205 having a third spike angle D between the second spike base 212 and the third spike side surface 214 or between the second spike base 212 and a portion of the third spike side surface 214, the one or more second spikes 205 having a fourth spike angle E between the second spike base 212 and the fourth spike side surface 215 or between the second spike base 212 and a portion of the fourth spike side surface 215, and the third spike angle C and the fourth spike angle D being between 30 and 60 degrees.

In one embodiment, the first spike angle A being equal to the second spike angle B and the third spike angle C being equal to the fourth spike angle D.

In one embodiment, the first spike angle A, the second spike angle B, the third spike angle C and the fourth spike angle D being equal to each other.

In one embodiment, the number of the one or more first spikes 105 in the spike arrangement 10 being between 1 and 30 and the number of the first stopper surfaces 106 being between 1 and 30.

In one embodiment, the number of the one or more first spikes 105 being equal to the number of the first stopper surfaces 106.

In one embodiment, the number of the one or more second spikes 205 in the spike arrangement 10 being between 1 and 30 and the number of the second stopper surfaces 206 being between 1 and 30.

In one embodiment, the number of the one or more second spikes 205 being equal to the number of the second stopper surfaces 206.

In one embodiment, the one or more first stopper surfaces 106 having a first stopper surface thickness T2 in a direction between the first side edge 100 and the second side edge 101, and the first stopper surface thickness T2 being between 5 mm and 15 mm.

In one embodiment, the one or more second stopper surfaces 206 having a second stopper surface thickness T3 in a direction between the first side edge 100 and the second side edge 101, and the second stopper surface thickness T3 being between 5 mm and 15 mm.

In one embodiment, the spike arrangement 10 having a spike arrangement thickness T1 in a direction between the first side edge 100 and the second side edge 101, and the spike arrangement thickness T1 being between 5 mm and 30 mm.

In one embodiment, the first stopper surface thickness T2 being between 0,1 and 0,6 times the spike arrangement thickness Tl.

In one embodiment, the second stopper surface thickness T3 being between 0,1 and 0,6 times the spike arrangement thickness Tl.

In one embodiment, the spike arrangement 10 having a spike top distance L8 between the first spike top 116 and the second spike top 216. The spike top distance L8 extending in a direction between the first side edge 100 and the second side edge 101. The spike top distance L8 being between 0,2 and 0,7 times the spike arrangement thickness Tl.

Figure 14 shows an embodiment of the spike arrangement 10 which is provided on a feed roller 500 comprising a tubular body 800. The tubular body 800 may be made for instance from a steel tube.

In one embodiment, a plurality of the spike arrangements 10 is provided to the feed roller 500.

In one embodiment, the spike arrangement 10 is welded to the tubular body 800.

In one embodiment, the feed roller body 501 comprises a tubular body 800 and a motor mounting plate 801.

In one embodiment, the motor mounting plate 801 is provided to an inner surface 802 of the tubular body 800. The motor mounting plate 801 is arranged transverse relative to the tubular body 800. The inner surface 802 of the tubular body 800 defines an empty space inside the tubular body 800. The feed roller motor 601 may be mounted to the motor mounting plate 801. The embodiments shown in figures 14 may comprise the features shown in figures 1-4 and 15.

Figure 15 shows an embodiment of the spike arrangement 10 which is provided on a feed roller 500. In this embodiment the spike arrangement 10 is arranged to taper in the direction of the rotation axis R.

In other words, the feed roller 500 having a first diameter DI and a second diameter, and the first diameter DI is greater than the second diameter D2.

In one embodiment, the feed roller 500 having a first diameter DI and a second diameter, and the first diameter DI is greater than the second diameter D2 at the first end 102 of the plurality of the spike arrangements 10. In one embodiment, a plurality of the spike arrangements 10 is provided to the feed roller 500.

In one embodiment, the feed roller body 501 comprises the motor mounting plate 801 The feed roller motor 601 may be mounted to the motor mounting plate 801 so that the feed roller motor 601 extending from the motor mounting plate 801 towards the first end 102 of the spike arrangement 10 or towards the plurality of the spike arrangements 10.

In one embodiment, the feed roller body 501 comprises one or more spike arrangement support plates 803 arranged to support the plurality of the spike arrangements 10.

The embodiments shown in figures 15 may comprise the features shown in figures 1-4 and 14.

Figure 16 shows an embodiment of the spike arrangement 10 which is provided on a feed roller 500.

In one embodiment, a plurality of the spike arrangements 10 is provided to the feed roller 500.

In one embodiment, the feed roller body 501 comprises the motor mounting plate 801. The feed roller motor 601 may be mounted to the motor mounting plate 801.

In one embodiment, the feed roller body 501 comprises one or more spike arrangement support plates 803 arranged to support the plurality of the spike arrangements 10.

The embodiments shown in figures 16 may comprise the features shown in figures 1-4, 14 and 15.

Figure 17 shows an embodiment of the spike arrangement 10.

In one embodiment, the one or more first spikes 105 having a first spike height Hl between the first spike top 113 and the first spike base 112. The spike arrangement 10 comprises one or more extended first spikes 105a. The one or more extended first spikes 105a comprise an extended first spike base 112a between one or more first stopper surfaces 106 and the first side edge 100 of the spike arrangement 10, The one or more extended first spikes 105a further comprise an extended first spike top 113a at distance from the extended first spike base 112a. The one or more extended first spikes 105a extending from the extended first spike base 112a to the extended first spike top 113a. The one or more extended first spikes 105a having an extended first spike height H la between the extended first spike top 113a and the extended first spike base 112a. The extended first spike height Hla being greater than the first spike height Hl. Respectively, the spike arrangement 10 may comprise the one or more second spikes 205 having a second spike height H2 between the second spike top 213 and the second spike base 212, and one or more extended second spikes having an extended second spike height between the extended second spike top and the extended second spike base. The extended second spike height being greater than the second spike height H2.

In one embodiment, the extended first spike height Hla being equal to the extended second spike height.

In one embodiment, the spike arrangement 10 comprises the one or more extended first spikes 105a and the one or more extended second arranged to extend from the second end 103 of the spike arrangement 10 towards the first end 102 of the spike arrangement 10.

In one embodiment, the spike arrangement 10 is provided on a feed roller 500.

The embodiments shown in figures 17 may comprise the features shown in figures 1-4 and 14-16.

Figures 5 to 9 show one embodiment of a feed roller 500 for a forest harvester head 600. The feed roller 500 comprises a feed roller body 501 arranged to be rotated around a rotation axis R and arranged to be operatively connected to a harvester head, a plurality of first spike arrangements 10a provided to the feed roller body 501 at the first circumference 502 from the rotation axis R, the plurality of first spike arrangements 10a is arranged to form a first circular row of spike arrangements 10a around the rotation axis R at a distance from the rotation axis R, and a plurality of second spike arrangements 10b provided to the feed roller body 501 at the first circumference 502 from the rotation axis R, the plurality of second spike arrangements 10b is arranged to form a second circular row of spike arrangements 10 at a distance from the rotation axis R. The first spike arrangements 10a are provided at a first distance from the adjacent second spike arrangements 10b along the first circumference 502.

In one embodiment, the feed roller body 501 comprises a first side 503 and a second side 504, the first side 503 and the second side 504 of the feed roller body 501 being transverse in relative to the rotation axis R, the second side 504 of the feed roller body 501 being at distance from the first side 503 of the feed roller body 501, the plurality of first spike arrangements 10a protruding from the first side 503of the feed roller body 501 in a direction away from the second side 504 of the feed roller body 501 and the plurality of second spike arrangements 10b protruding from the second side 504 of the feed roller body 501 in a direction away from the first side 503 of the feed roller body 501, the plurality of first spike arrangements 10a and the feed roller body 501 forming a plurality of first recesses 505, and the plurality of second spike arrangements 10b and the feed roller body 501 forming a plurality of second recesses 506.

In one embodiment, the first recess 505 having a first recess width RW1 along the first circumference 502, and the first recess width RW1 being between 10 mm and 70 mm.

In one embodiment, the second recess 506 having a second recess width RW2 along the first circumference 502, and the second recess width RW2 being between 10 mm and 70 mm.

In one embodiment, the feed roller body 501 comprises an outer surface 507 between the first side 503 and the second side 504 of the feed roller body 501, the outer surface 507 being at a distance from the rotation axis R, the feed roller body 501 comprises a plurality of first holding recesses 508 arranged to receive the plurality of first spike arrangements 10a and a plurality of second holding recesses 509 arranged to receive the plurality of second spike arrangements 10b, the plurality of first spike arrangements 10a protruding from the outer surface 507 of the feed roller body 501 in a direction away from the rotation axis R, and the plurality of second spike arrangements 10b protruding from the outer surface of the feed roller body 501 in a direction away from the rotation axis R.

In one embodiment, the feed roller body 501 comprises between 10 and 50 first spike arrangements 10a and between 10 and 50 second spike arrangements 10b.

The first spike arrangements 10a of the plurality of first spike arrangements 10a may be any embodiment of a spike arrangement 10 shown in figure 1 to 4 and the second spike arrangements 10b of the plurality of the second spike arrangements 10b may be any embodiment of a spike arrangement 10 shown in figure 1 to 4.

In one embodiment, the feed roller 500 having a plurality of feed roller radiuses RA extending from the rotation axis R to the first circumference 502, the spike plate 300 of each first spike arrangement 10a of the plurality of first spike arrangements 10a extending parallel to a feed roller radius RA such that the bottom surface 301 facing towards the rotation axis R, and the spike plate 300 of each second spike arrangement 10b of the plurality of second spike arrangements 10b extending parallel to a feed roller radius RA such that the bottom surface 301 facing towards the rotation axis R.

In one embodiment, a second angle K2 between adjacent first spike arrangements 10a of the plurality of first spike arrangements 10a being between 6 and 20 degrees.

In one embodiment, a second angle K2 between adjacent second spike arrangements 10b of the plurality of second spike arrangements 10b being between 6 and 20 degrees.

In one embodiment, a first angle K2 between adjacent first spike arrangements 10a and the second spike arrangements being between 3 and 10 degrees.

The feed roller 500 having a feed roller width W1 in direction parallel to the rotation axis R.

In one embodiment, the feed roller width W1 being between 50 mm and 400 mm.

The first spike arrangements 10a of the plurality of first spike arrangements 10a having a spike arrangement length L5 shown in figure 2.

The second spike arrangements 10b of the plurality of second spike arrangements 10b having a spike arrangement length L5 shown in figure 2.

In one embodiment, the spike arrangement length L5 being between 0,4 and 0,6 times the feed roller width Wl.

In one embodiment, the spike arrangement length L5 being between 20 mm and 400 mm.

In one embodiment, the one or more first spike arrangements 10a and the one more second spike arrangements 10b extending parallel.

In one embodiment, the first spike length LI being between 0,3 and 0,7 times the feed roller width Wl.

In one embodiment, along the first circumference 502 a distance between one or more first spikes of the one or more first spike arrangements 10a and one or more second spikes of the one or more second spike arrangements 10b being equal to along the first circumference 502 a distance between the one or more first spikes and the one or more second spikes of the one or more first spike arrangements 10a.

In other words, each spikes of the feed roller 500 are arranged at an equal distance along the first circumference 502 from an adjacent spike. Figures 12 and 13 show schematically a feed roller according to one embodiment of the present invention.

In this embodiment, the plurality of first spike arrangements 10a is provided on the feed roller body 501 and arranged to extend on the feed roller body 501 a first overlapping distance OD1. The plurality of second spike arrangements 10b is provided on the feed roller body and arranged to extend on the feed roller body a second overlapping distance OD2.

In one embodiment, the first overlapping distance OD1 is greater than the second overlapping distance OD2.

In one embodiment, the second overlapping distance OD2 is 0,3 - 0,7 times the first overlapping distance OD1.

In one embodiment, the feed roller body 501 having a feed roller body thickness FT between the first side 503 of the feed roller body 501 and the second side 504 of the feed roller body 501.

In one embodiment, the feed roller body thickness FT is equal to the first overlapping distance OD1.

The embodiments shown in figures 5 - 9 may comprise the features shown in figures 12 and 13.

Figure 10 shows a forest harvester head 600 according to one embodiment of the present invention. The forest harvester head 600 comprises one or more a feed rollers 500. The one or more a feed rollers 500 may be any embodiment of the feed roller 500 shown in figures 5 - 9.

The feed rollers 500 comprising a feed roller body 501 arranged to rotate around a rotation axis R and the feed roller body 501 being operatively connected to a feed roller motor 601, a plurality of first spike arrangements 10a provided to the feed roller body 501 at the first circumference 50 from the rotation axis R, the plurality of first spike arrangements 10a is arranged to form a first circular row of spike arrangements 10a around the rotation axis R at a distance from the rotation axis R, a plurality of second spike arrangements 10b provided to the feed roller body 501 at the first circumference 502 from the rotation axis R, the plurality of second spike arrangements 10b is arranged to form a second circular row of spike arrangements 10b at a distance from the rotation axis R, the first spike arrangements 10a are provided at a first distance along the first circumference 502 from the adjacent second spike arrangements 10b.

Typically, forest harvester is a heavy forestry vehicle employed in cut- to-length logging operations for felling, delimbing and bucking trees. A forest harvester is typically employed together with a forwarder that hauls the logs to a roadside landing. A typical harvester head consists of (from bottom to top, with head in vertical position):

- a chain saw to cut the tree at its base, and cut it to length. The saw is hydraulically powered, rather than using the 2 -stroke engine of a portable version. It has a stronger chain and a higher power output than any saw a person can carry,

- two or more curved delimbing knives which reach around the trunk to remove branches,

- between two to four feed rollers to grasp the tree. The wheels pivot apart to allow the harvester head to grasp the tree and pivot together to hug the tree tightly. The wheels are driven in rotation to force the cut tree stem through the delimbing knives. The harvester head comprises a feed roller motor for each feed roller to rotate feed rollers ,

- diameter sensors to calculate the volume of timber harvested in conjunction with, and

-a measuring wheel which measures the length of the stem as it is fed through the head.

One operator in the vehicle's cab can control all of these functions. A control computer can simplify mechanical movements and can keep records of the length and diameter of trees cut. Length is computed by either counting the rotations of the gripping wheels or, more commonly, using the measuring wheel. Diameter is computed from the pivot angle of the gripping wheels or delimbing knives when hugging the tree. Length measurement also can be used for automated cutting of the tree into predefined lengths.

It should be noted that the feed rollers are arranged to move trees in two directions.

The invention has been described above with reference to the examples shown in the figures. However, the invention is in no way restricted to the above examples but may vary within the scope of the claims.