WO2008054196A1

WO2008054196A1 - Device for felling a tree

Info

Publication number: WO2008054196A1
Application number: PCT/NL2007/000264
Authority: WO
Inventors: Franciscus Adrianus Raaijmakers
Original assignee: Raaijmakers Franciscus Adrianu
Priority date: 2006-10-31
Filing date: 2007-10-16
Publication date: 2008-05-08

Abstract

The invention relates to a device for felling a tree, comprising a frame to be coupled to the boom of an operating machine or the like, a gripping tool connected to the frame for engaging a part of the tree to be felled, as well as a separating tool connected to the frame for separating said part of the tree to be felled. The object of the invention is to provide a device of the kind referred to in the introduction, which enables a more versatile use and which, as a result of an improved manoeuvrability of the felling tool, is capable of carrying out operations also at places that were previously considered to be difficult to reach. According to the invention, the device is to that end characterised in that the device comprises a further separating tool connected to the frame, which two tools are disposed on either side of the gripping tool and which frame can be rotatably coupled to the boom.

Description

DEVICE FOR FELLING A TREE

DESCRIPTION

The invention relates to a device for felling a tree, comprising a frame to be coupled to the boom of an operating machine or the like, a gripping tool connected to the frame for engaging a part of the tree to be felled, as well as a separating tool connected to the frame for separating said part of the tree to be felled.

For a clear understanding, the term "operating machine" as used herein is understood to include all kinds of machines that can be fitted with a boom, among which excavators as well as cranes, which may or may not be provided with an extendable boom.

Such a device is frequently used for lopping and/or felling trees. The known devices are arranged for felling trees in one go, for example by clamping a gripper element coupled to the boom round the trunk and cutting off the trunk near the ground by means of a separating tool, for example in the form of a circular saw. The tree is then lowered to the ground in a controlled manner and carried off or mechanically processed into manageable parts in situ.

With the devices that are currently known, the extent to which the gripping and separating tools can be positioned with respect to the tree to be processed is quite limited, being fully dependent on the manoeuvrability of the boom to which the felling device is coupled. The generally robust construction of the boom as well as its dimensions and mass stand in the way of a flexible and precise positioning of the felling tool with respect to the tree to be felled, and consequently they are limiting factors as regards the usability of the devices that are currently known.

The object of the invention is to overcome the aforesaid drawback and to provide a device of the kind referred to in the introduction, which enables a more versatile use and which, as a result of an improved manoeuvrability of the felling tool, is capable of carrying out operations also at places that were previously considered to be difficult to reach. According to the invention, the device is to that end characterised in that the device comprises a further separating tool connected to the frame, which two tools are disposed on either side of the gripping tool and which frame can be rotatably coupled to the boom. This makes it possible to position the felling device more accurately within a smaller positioning space relative to the boom and consequently to the tree to be handled. The felling device can now also carry out operations at locations which previously could not be reached merely by manoeuvring the boom. Said more accurate positioning within a smaller positioning space of the felling device makes it possible to fell a tree in stages ("limb by limb") rather than in one go. This makes it possible to use the device in residential areas, for example, where it is not possible to fell a tree in one go in connection with the presence of obstacles (houses, lamp posts, cars, etc.). In a very functional embodiment of the device according to the invention, which makes it possible to position the gripping and separating tools very precisely relative to the boom and the tree, the two separating tools and the gripping tool are mounted on a rotatable support plate.

More specifically, rotating means are provided for rotating the support plate, which rotating means are according to one embodiment configured as a rotatable column.

According to another embodiment, in order to obtain a precise rotation and thus positioning relative to the tree to be felled, the rotating means comprise a rotatable flanged edge, whilst furthermore clamping means engaging round said edge are provided.

Said clamping means are furthermore connected to the non- rotatable part of the frame.

To realise a simple refitting of the felling device with a different type of separating tool, each separating tool is mounted on a mounting plate that is fixed to the frame.

The invention further relates to a device for felling a tree, comprising a frame to be coupled to the boom of an operating machine or the like, a gripping tool connected to the frame for engaging a part of the tree to be felled.

According to another aspect of the invention, the frame can be rotatably coupled to the boom, with the gripping tool being mounted on a support plate that can be rotated by rotating means. This aspect, too, makes it possible to position the felling device more accurately within a small positioning space relative to the boom and thus to the tree to be handled. The felling device can now also carry - out operations at locations which previously could not be reached merely by manoeuvring the boom.

The invention will now be explained in more detail with reference to a drawing, in which:

Figure 1 shows an embodiment of a device according to the invention;

Figure 2 is a plan view of figure 1 ;

Figures 3 and 4 are detailed views of figure 2;

Figure 5 is a cross-sectional view of the device of figure 1 ;

Figures 6a and 6b show another embodiment of a device according to the invention.

For a clear understanding, identical parts are indicated by the same numerals in the drawings.

Figure 1 is a view of an embodiment of a device according to the invention for felling a tree. The device for felling a tree is indicated at 1 in the figures and comprises a frame 10-11 that can be coupled to the boom of an excavator. The frame 10-11 is connected to a gripping tool 20 arranged for engaging a part of the tree to be felled. The gripping tool 20 comprises two clamping jaws 21a-21 b, which can be moved towards and away from each other in a suitable manner which is known to the skilled person, in particular by means of drive hydraulics. Said drive hydraulics may comprise piston-cylinder combinations

(not shown) that can be actuated by means of the hydraulic system of the operating machine, for example of an excavator or an (extendable) crane. To obtain a better grip of the gripping elements 21 a-21b round a part of the tree to be felled, the gripping tool 20 furthermore comprises a contact surface 22 provided with projecting teeth. Said projecting teeth 22 engage in the bark of the tree to be felled and thus prevent the tree from undesirably shifting or becoming detached during the felling operations.

Likewise shown in figures 1 , 2 and 5 are a pair of separating tools 30-40, which are according to a first aspect of the invention disposed on either side of the gripping tool 20. Each separating tool 30-40 (constructed as a chainsaw 32-42 in this embodiment) is disposed within a guard 31 -41 , which functions to screen or store the moving parts during the time the felling device is not being operated. The guard 31-41 of each separating tool 30-40 also provides space for the drive units 33- 43 (see figure 2), for example electric motors. Although the embodiment shown in the figures discloses two chainsaws 30-40 are disposed on either side of the gripping tool, it will be understood that also other types of separating tools may be used. Think, for example, of circular saws, shears, hedge clippers and/or band saws etc, etc in this connection.

According to another aspect of the invention, the two separating tools 30-40 and the gripping tool 20 are mounted on a support plate 15, which is rotatably accommodated in the device. The frame 10-1 1 is to that end made up of a part 10, which can be rotatably driven, and a part 11 , which forms the fixed structure and which is coupled, by means of a coupling mechanism that is known to the skilled person, to the boom (not shown) of an excavator. The rotatable part 10 is configured as a rotatable column, the rotation of which is effected by means of drive hydraulics, for example. The fixed structure 11 is to that end provided with nipples 12, to which supply and discharge lines for a hydraulic medium (for example oil) can be connected.

The rotation of the column 10 and the support plate 15 and of the separating tools 30-40 and the gripping tool 20 mounted on the support plate 15 is effected from the cabin of the operating machine, with the operator controlling the drive hydraulics in such a manner that a hydraulic medium (oil) is carried to and from the rotatable column 10 under pressure via the nipples 12.

Brake means 14 are provided for controlling the rotation of the column 10 (and the support plate 15) relative to the fixed structure 1 1 . Said brake means are attached to the fixed structure 1 1 and engage a flanged edge 13 on the rotatable column 10. The brake means 14 are shown in more detail in figures 2-5. Rotation of the rotatable column 10 together with the support plate

15 results in rotation also of the flange 13 relative to the part 1 1 forming the fixed structure, to which the brake means 14 are attached. The brake means 14 extend round the rotating flange 13 and are provided with a brake shoe 14', which can be pressed against the rotating flange 13, for example by means of the drive hydraulics of the operating machine (excavator).

The brake shoe 14' thus exerts a braking action on the rotating flange 13, which makes it possible to orient the rotating column 10 and the support plate 15, and thus also the separating tools 30-40 and the gripping tool 20 mounted on the support plate, in a random orientation relative to the tree to be felled. Thus, a felling device exhibiting an improved manoeuvrability is realised, making it possible to carry out work also at places that were previously difficult to reach.

In addition, the symmetric construction around the axis of rotation

(formed by the rotating column 10) results in a precisely balanced frame, making it possible to realise a smooth and accurate positioning of the gripping tool 20 and the separating tools 30-40 relative to a part of the tree. The range of applications of the felling device according to the invention is thus significantly enhanced/widened.

To realise a simple arrangement of the felling device 1 , the support plate 15 is provided with two vertically extending mounting plates 34-44 disposed on either side of the gripping tool 20, to which the guards 31 -41 of each of the separating tools 30-40 can be attached, using simple means of attachment. This makes it possible to refit the device according to the invention by removing a specific type of separating tool and exchange it for a different type of separating tool, which is connected to the mounting plate 34-44 in a corresponding manner. The two gripping jaws 21 a-21 b are pivotable relative to each other about pivot pins 23a-23b, of which only the pivot pin 23a, about which the clamping jaw 21 a pivots, is shown in figure 2 for the sake of clarity. The two pivot pins 23a- 23b are mounted between two spaced-apart plates. It will be understood that the felling device according to the invention provides a much more versatile apparatus exhibiting an improved manoeuvrability, making it possible not only to carry out work at places that were previously difficult to reach but, in addition, also to realise a smooth and accurate positioning of the separating tools and the gripping tool relative to the tree to be felled.

Figures 6a and 6b show another embodiment of a felling device according to the invention. In this embodiment, said at least one separating tool 40 is movable relative to the frame, and more in particular relative to the column 10. To that end the frame comprises a guide 51 , along which the drive unit 43 of the separating tool 40 can be moved. To that end suitable moving means 50 are provided, which enable the separating tool 40 to move along a guide 51. As shown in figures 6a and 60b, the guide 51 has a curved configuration, making it possible to reorient the separating tool 40, and more in particular the chainsaw or the saw blade 42, relative to the clamping tool 21 a-21 b.

In practice a situation may occur in which the clamping tool 21 a-21 b can only clamp down a limp or trunk to be separated in one position, so that the separating tool 40 can cut through the limp of the trunk in question only from below or from aside. In practice this may result in the felling device getting jammed or damaged, because the weight of the limb or the trunk to be separated may cause the saw blade 42 to become wedged and seize. By reorienting the saw blade 42 relative to the clamping means 21a-

21 b in accordance with the invention, a limb or a trunk to be separated can be cut through essentially from the upper side, as a result of which the saw-cut will open under the influence of the force of gravity, i.e. the weight of the part of the limb/trunk to be separated, thus preventing the saw blade 42 from becoming wedged in de saw-cut. Repositioning the separating tool 40 relative to the frame or the clamping means 21 a-21 b furthermore makes it easier to separate a limb or a trunk, since the force of gravity makes it easier to separate a limb or trunk by making a saw-cut essentially from above.

Claims

I . A device for felling a tree, comprising a frame to be coupled to the boom of an operating machine or the like, a gripping tool connected to the frame for engaging a part of the tree to be felled, as well as a separating tool connected to the frame for separating said part of the tree to be felled, characterised in that the device comprises a further separating tool connected to the frame, which two tools are disposed on either side of the gripping tool and which frame can be rotatably coupled to the boom. 2. A felling device according to claim 1 , characterised in that the two separating tools and the gripping tool are mounted on a rotatable support plate.

3. A felling device according to claim 2, characterised in that rotating means are provided for rotating the support plate.

4. A felling device according to claim 3, characterised in that said rotating means are configured as a rotatable column.

5. A felling device according to claim 3 or 4, characterised in that said rotating means comprise a rotatable flanged edge, whilst furthermore clamping means engaging round said edge are provided.

6. A felling device according to claim 5, characterised in that said clamping means are connected to the non-rotatable part of the frame.

7. A felling device according to claim 5, characterised in that each separating tool is mounted on a mounting plate that is fixed to the frame.

8. A device for felling a tree, comprising a frame to be coupled to the boom of an operating machine or the like and a gripping tool connected to the frame for engaging a part of the tree to be felled, characterised in that the frame can be rotatably coupled to the boom, with the gripping tool being mounted on a support plate that can be rotated by rotating means.

9. A felling device according to claim 8, characterised in that said rotating means are configured as a rotatable column. 10. A felling device according to claim 8 or 9, characterised in that said rotating means comprise a rotatable flanged edge, whilst furthermore clamping means engaging round said edge are provided.

I I . A felling device according to claim 10, characterised in that said clamping means are connected to the non-rotatable part of the frame. 12. A felling device according to claim 11 , characterised in that the device further comprises at least one separating tool connected to the frame for separating said part of the tree to be felled. 13. A felling device according to claim 12, characterised in that said at least one separating tool is mounted on a mounting plate that is fixed to the frame.

14. A felling device according to claim 12 or 13, characterised in that the device comprises a further separating tool connected to the frame, which two tools are disposed on either side of the gripping tool and which frame can be rotatably coupled to the boom.

15. A felling device according to any one or more of the preceding claims, characterised in that said at least one separating tool is movable relative to the frame.

16. A felling device according to claim 15, characterised in that said at least one separating tool is movable over a guide provided on the frame.

17. A felling device according to claim 15, characterised in that said guide has a curved configuration.