GB2602312A

GB2602312A - Tree felling wedge system

Info

Publication number: GB2602312A
Application number: GB2020446.7A
Authority: GB
Inventors: Kjell Eriksson Eckhard
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-12-22
Filing date: 2020-12-22
Publication date: 2022-06-29
Anticipated expiration: 2040-12-22
Also published as: GB2602312B; GB202020446D0

Abstract

A tree felling wedge system 5 and method of use comprises a first wedge 6 comprising a guiding structure (7, figure 2a) and a second wedge 9 configured to be guided by the guiding structure (7) of the first wedge 6. The guiding structure may preferably comprise of a slot (8, figure 2a) wherein the second wedge is configured to slide in the slot. The guiding structure (7) of the first wedge 6 may also comprise two or more slots (8a, 8b, figure 3a) separated by a ridge (15, figure 3a) and the second wedge may comprise corresponding slots for accommodating ridge (15).The second wedge may additionally comprises top surface comprising teeth that engage with the tree and prevent the second wedge from sliding backwards. The system 5 additionally comprises the first wedge comprising a plurality of notches (21, figure 4) and the second wedge comprises corresponding teeth (20, figure 4) for engagement with the notches to prevent the second wedge from sliding backwards when in use.

Description

Tree Felling Wedge System

Technical field

The invention relates to tree felling wedges and in particular wedges that can cooperatively interact.

Background

Tree feeling wedges have been used for many years to assist in the controlled felling of trees. An initial cut is made into the trunk of the tree, typically using a chain saw. A hard wedge is pushed with the tapered end first into the cut. A hammer or sledge is used to further force the wedge into the trunk, thereby opening the cut as the wider back-end of the wedge is driven into the tree and causing the tree to fall.

Importantly, the tree will tend to fall away from the side of the wedge and the person felling the tree.

Figure 1 shows schematic diagram of a conventional setup for felling a tree 1 using a felling wedge 2. The wedge 1 is lodged in a cut 3 in the tree 2, and a sledge 4 is used to drive the wedge 1 further into the cut 3 in order to fell the tree.

Whilst using a felling wedge can improve control of the tree felling process, there is still some risk to the operator and there is a continued need for making the felling process safer.

Summary

According to a first aspect of the present invention there is provided a tree felling wedge system. The system comprises a first wedge comprising a guiding structure and a second wedge configured to be guided by the guiding structure of the first wedge. The guiding structure can allow the second wedge to slide longitudinally (i.e. along the longitudinal axis of the first wedge), while preventing the second wedge from slipping sideways. Hence, if the first wedge is not sufficient, a second wedge can be inserted on the first wedge to facilitate felling of a tree.

The guiding structure may include a slot, so that the second wedge can slide in the slot. The slot may be horizontal or declined at an angle. The slot may extend substantially the entire length of the first wedge or may be shorter. For example, the slot may cover between 50% to 90% of the length of the first slot.

The depth of the slot decreases towards the front of the first wedge. At the back of the first wedge, the slot may have a depth in the range of 10% to 60% of the thickness of the first wedge. The first wedge comprises an edge portion on either side of the slot, and the width of the edge portion may be greater than 10 mm, and in a preferred embodiment is about 15 mm.

The second wedge may comprise a second guiding structure for cooperating with the guiding structure of the first wedge. For example, the guiding structure of the first wedge may comprises two or more slots separated by a ridge or ridges, and the second guiding structure then comprises corresponding slots for accommodating the ridge or ridges. Having more than one slot can increase the lateral stability, to further reduce the risk of the second wedge slipping off sideways. The ridge or ridges may be lower compared to the edge portions, to make insertion of the second wedge easier. The slots in the first wedge may have a pitch in the range of 30 mm to 100 mm.

The second wedge comprises a top surface for contacting the tree, and the top surface may comprise one or more teeth for engaging the tree and preventing the second wedge from sliding backwards while allowing the wedge to slide forwards when in use. The teeth may be any type of suitable raised portion(s) on the top surface, but are preferably angled to allow the second wedge to preferably slide forwards (into the tree).

The first wedge may comprise a plurality of notches and the second wedge corresponding teeth for engaging the notches and thereby preventing the second wedge from sliding backwards while allowing the second wedge to slide forwards when in use. For example, the first wedge may comprise notches at the bottom of a slot of the guiding structure.

According to a second aspect of the present invention there is provided a wedge for use as the first wedge of the first aspect of the invention.

According to a third aspect there is provided a method of felling a tree. The method comprises making a cut into the tree (e.g. using a chainsaw) and inserting a first wedge in the cut, wherein the first wedge comprises a guiding structure. Then, inserting a second wedge in the cut, wherein the second wedge is guided by the guiding structure of the first wedge.

Preferred embodiments will now be described with reference to the accompanying drawings.

Brief description of drawings

Figure 1 shows a conventional setup for felling a tree with a felling wedge; Figure 2a shows a schematic diagram of a tree felling wedge according to an embodiment; Figure 2b shows a tree felling wedge system comprising the tree felling wedge and a second cooperating wedge according to an embodiment; Figure 2c shows a back view of the tree felling wedge; Figure 2d shows a side view of the tree felling wedge; Figure 3a shows a tree felling wedge according to another embodiment comprising two slots; Figure 3b shows a back view of the tree felling wedge; Figure 3c shows a top view of the tree feeling wedge; Figure 3d shows a back view of a second wedge for cooperating with the first tree felling wedge; Figure 3e shows a bottom view of the second wedge; and Figure 4 shows another embodiment of the tree felling wedge system.

Detailed description

It can be difficult to accurately gauge the appropriate size of wedge to be used for a particular tree and cut. If the wedge is too thick, then it will be difficult to insert and the wedge may slip out to one side. If the wedge is too small, then the tree will not fall even when the wedge is fully inserted. At this point it is nearly impossible and also very dangerous to attempt to remove the wedge in order to replace it. In this case, it may be possible to insert a second, wedge above or below the first wedge to further widen the cut and fell the tree. Again, this process is associated with an increased risk due to the tendency of the second wedge to slip sideways on the first wedge.

Embodiments of the present invention solve these problems by providing two cooperating wedges, wherein at least one of the wedges comprises a guiding structure for guiding the second wedge and thereby prevent the second wedge from slipping sideways.

Figures 2a to 2d show a first embodiment of a tree felling wedge system 5 comprising a first wedge 6 having a guiding structure 7 comprising a slot 8 configured to receive the second wedge 9. The second wedge 9 has a width 10. The first wedge 6 needs to have a greater width, to both accommodate the slot 8 and provide sufficient surface area on either side of the slot 8. The slot 8 in the wedge 6 defines edge portions 11 on either side of the slot 8. The edge portions 11 have a width 12 (equal to the total width 13 of the wedge 6 minus the width 14 of the slot 8 and divided by two). The width 12 of the edges 11 should be sufficient to prevent the edge portions 11 from sinking into the wood of the tree trunk, and thereby causing the slot 8 to be blocked by the tree trunk, as this can make insertion of the second wedge 9 more difficult. The minimum width required will depend on various factors, such as the type of wood, the height of the tree and, to some extent, the material of the wedge. However, in general, a width 12 of more than mm is recommended. In an embodiment particularly useful for soft timber (e.g. pine) the width 12 is 15 mm.

Figure 2a shows a schematic diagram of the first wedge 6 having a single slot 8 and edge portions 11. The edge portions having a width 12 sufficient to leave a gap in the slot 8 for inserting the second wedge 9 when inserted into a tree. Figure 2b shows the tree felling wedge system 5 with the first wedge 6 and the second wedge 9 partly inserted into the slot 8 of the first wedge 6. The width 13 of the second wedge 9 corresponds to the width 14 of the slot 8, with some tolerance to make sure the second wedge Scan slide into the slot 8 without getting stuck. Figure 2c shows the first wedge 6 from the back. The edge portions 11 have substantially straight sides, but may in other embodiments be slightly angled outwards (e.g. 5 to degrees off the vertical axis) to reduce the risk of pinching, while still preventing the second wedge 8 from sliding sideways off the first wedge 6. Figure 2d shows a side view of the first wedge 6. The dashed line indicates the bottom of the slot 8, which is obscured by the edge portion 11.

Figures 3a to 3e show a second embodiment of the tree felling wedge system 5. Similar or equivalent features in different figures may have the same reference numerals to aid understanding and are not intended to limit the illustrated embodiments. The wedge 6 has a guiding structure 7a comprising two slots 8a and 8b defining edge portions 11 and a central portion 15 being a ridge in between. The edge portions have a width 12, and the central portion has a width 16, which may be the same as the width 12 of the edge portions 11.The width 12 of the edge portions 11 may be smaller compared to an embodiment including one slot, since the central portion 15 provides additional support against the tree when in use and the widths 14a and 14b of the respective slots is relatively small, hence reducing the risk of the tree blocking the slots 14a and 14b when in use. Figure 3b shows the first wedge 6 from the back and Figure 3c shows a top view of the wedge 6. Although the central portion 15 is illustrated as substantially level with the edge portions 11, in some embodiments the central portion 15 is sunken compared to the edge portions 11. For example, the central portion 15 may be half the height of the edge portion 11 measure from the bottom of the slots 8a and 8b at the back of the wedge 6. This can provide a small gap above the

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central portion 15 or at least reduce the pressure from the tree on the central portion 15, when in use, which can make insertion of the second wedge easier.

Figure 3d shows a back view of a second wedge 9 having a corresponding guiding structure 7b for cooperating with the guiding structure 7a of the first wedge 6, to allow the second wedge 9 to slide longitudinally on the first wedge 6 and into the tree. The guiding structure 7b of the second wedge 9 comprises a slot for accommodating the central portion 15 of the first wedge 6. Hence, the second wedge 9 is free to slide longitudinally forwards on the first wedge 6, while being prevented from sliding sideways. Figure 3e shows a bottom view of the second wedge 9.

Figure 4 shows a side view of a third embodiment of the tree felling wedge system 5, comprising a first wedge 6 and a second wedge 9. The first wedge comprises a slot 8, into which the second wedge 9 is configured to slide. The second wedge comprises a top surface 17 for engaging the tree and a bottom surface 18 for engaging the first wedge 6. The top surface 17 comprises a plurality of teeth 19, being raised portions on the surface 17 of the wedge 9. The teeth 19 are slanted so as to allow the wedge 9 to slide forward while preventing the wedge 9 from sliding backward (out of the tree). The bottom surface 18 also comprises a plurality of teeth 20 for gripping the first wedge 6. Since the first wedge 6 is relatively hard, the slot 8 comprises a plurality of notches 21, corresponding to the teeth 20 on the bottom surface 18, to enhance the grip between the wedges 6 and 9 and thereby further reduce the risk of the second wedge 9 sliding out backwards when in use. Other embodiments of the system 5 may comprise only one set of teeth on either the top 17 or bottom 18 surface of the second wedge 9.

While specific embodiments of the invention have been described above, further embodiments falling within the scope of the claims will be apparent to the skilled person Features of different embodiments may be combined.

Claims

CLAIMS1. A tree felling wedge system (5) comprising: a first wedge (6) comprising a guiding structure (7) and a second wedge (9) configured to be guided by the guiding structure (7) of the first wedge (6).
2. A tree felling wedge system (5) according to claim 1, wherein the guiding structure (7) comprises a slot (8), and wherein the second wedge (9) is configured to slide in the slot (8).
3. A tree felling wedge system (5) according to claim 2, wherein the first wedge (6) comprises an edge portion (11) on either side of the slot (8), and wherein a width (12) of the edge portion (11) is greater than 10 mm.
4. A tree felling wedge system (5), according to claim 3, wherein the edge portion (11) has a width (12) of 15 mm.
5. A tree felling wedge system (5) according to any one of the preceding claims, wherein the second wedge (9) comprises a second guiding structure for cooperating with the guiding structure (7) of the first wedge (6).
6. A tree felling wedge system (5) according to any one of the preceding claims, wherein the guiding structure (7) of the first wedge (6) comprises two or more slots (8a, 8b) separated by a ridge (15) or ridges, and the second guiding structure comprises corresponding slots for accommodating the ridge (15) or ridges.
7. A tree felling wedge system (5) according to claim 6, wherein the ridge or ridges are lower compared to the edge portions (11).
8. A tree felling wedge system (5) according to claim 6 or 7, wherein the slots (8a, 8b) in the first wedge (6) have a pitch in the range of 30 mm to 100 mm.
9. A tree felling wedge system (5) according to any one of the preceding claims, wherein the second wedge (9) comprises a top surface for contacting a tree, wherein the top surface comprises one or more teeth for engaging with the tree and preventing the second wedge from sliding backwards out of the tree while allowing the wedge to slide forwards into the tree when in use.
10. A tree felling wedge system (5), wherein the first wedge (6) comprises a plurality of notches (21) and the second wedge (9) comprises corresponding teeth (20) for engaging the notches (21) and thereby prevent the second wedge (9) from sliding backwards out of the tree while allowing the second wedge (9) to slide forwards into the tree when in use.
11. A wedge for use as the first wedge (6) in a tree felling system (5) according to any one of the preceding claims.
12. A method of felling a tree comprising: making a cut into the tree; inserting a first wedge in the cut, wherein the first wedge comprises a guiding structure; and inserting a second wedge in the cut, wherein the second wedge is guided by the guiding structure of the first wedge.