WO2005060734A1

WO2005060734A1 - A delimbing apparatus and a feeding member for the same

Info

Publication number: WO2005060734A1
Application number: PCT/FI2004/050185
Authority: WO
Inventors: Timo Neuvonen
Original assignee: Plustech Oy
Priority date: 2003-12-22
Filing date: 2004-12-14
Publication date: 2005-07-07
Also published as: SE529930C2; FI118032B; SE0501826L; FI20031882A0; FI20031882A

Abstract

A delimbing apparatus and a feeding member for the same. The feeding member is arranged to feed tree trunks through the delimbing apparatus (1), it is mounted in a rotatable manner on the delimbing apparatus (1) and is arranged to close to a position in which it is intended to be placed against a tree trunk in the delimbing apparatus as well as to open to a position which makes it possible to use the delimbing apparatus for the loading of one or more tree trunks. The delimbing apparatus also comprises a cylinder actuator (10) arranged to open and close said feeding member (3). A coupling (11, 21) is provided between said cylinder actuator (10) and said feeding member (3), which coupling can be transferred to a position (C, Cc) in which the movement of extending or contracting the cylinder actuator (10) effects the closing of the feeding member (3). Said coupling (21) can also be transferred to a position (B, Bb) in which the same movement of extending or contracting the cylinder actuator (10) effects the opening of the feeding member (3). In one embodiment, the cylinder actuator (10) is coupled to said feeding member (3) by a mechanism (11, 21) to change the position, and furthermore, the position of said cylinder actuator (10) remains unchanged.

Description

A DELIMBING APPARATUS AND A FEEDING MEMBER FOR THE SAME

The invention relates to a delimbing apparatus with a feeding member according to the preamble of claim 1. The invention also relates to a delimbing apparatus with a feeding member according to the preamble of claim 5.

For the manipulation of tree trunks, a harvester head is used, whose purpose is to grip an upright growing tree, to cut the tree and to fell it. After this, the harvester head delimbs the tree trunk and cuts it into pieces of fixed length. The harvester head is normally mounted by joints at the end of the boom assembly of a forest machine. The working machine is particularly a harvester which moves on a terrain by means of wheels or a crawler. Some harvester heads are also used in forwarders and for the loading of the trunk, wherein they are also provided with grapple members turnable with respect to the frame structure pairwise on different sides of the trunk. The grapple may also consist of blades for delimbing. US 5,186,227 presents a harvester head and a forwarder. The harvester head comprises the necessary actuator members, normally hydraulic cylinders and hydraulic motors which can be used to control the position and the different functions of the harvester head.

The harvester head, which is also called a delimbing apparatus or a manipulating apparatus for tree trunks, is also provided with delimbing members which are pivotable in a controlled meanner in relation to the frame structure. These members are normally placed as a pair on different sides of the tree trunk. The delimbing members comprise delimbing blades to cut off the branches while the trunk is being carried and transported through the apparatus. The harvester head may also be provided with a second pair of delimbing members or a single delimbing member. The feeding members normally comprise a drive wheel or a chain track which is pressed against the trunk in a controlled manner and pulls it past the delimbing blades and through the apparatus. The feeding members are normally placed as a pair on different sides of the tree trunk. The head is also provided with cutting members, such as a chain saw for performing the cutting and felling of the trunk.

Various types of harvester heads are known, which are suitable for both the delimbing and the handling of tree trunks during their loading as well as unloading. SE 507930 C2 presents a harvester head which comprises grapples for supporting the tree, feed rolls being placed in the grapples. The position of the feed rolls can be changed so that they would not touch the tree trunks in the grapple during the loading. FI 108606 B presents an apparatus developed for the same purpose, wherein the position of the feed rolls is affected by means of an actuator. The feed rolls can also be placed separately from the grapples, and the tree trunks are manipulated by the same members that are used for delimbing, i.e. the delimbing blades.

According to US 5,785,101 , the feed rolls can be opened to be out of the way during the loading. According to said publication, the position of the feed wheels is controlled by means of two cylinder actuators, wherein one can be used to lift the feed wheels considerably higher than the delimbing blades.

However, a problem with the prior art lies in the insufficient play or particularly in the complexity of the structures, if wide movements of the grapple or the blades, or a transfer of the feeding members sufficient far away are desired for the loading. In said publication, it is necessary, for example, to have one extra joint and an actuator to move the feed wheels at the ends of the arms sufficiently far away for the largest possible opening of the delimbing blades so that the feeding members would not touch the tree trunks.

It is an aim of the present invention to eliminate the drawbacks presented above. A delimbing apparatus with a feeding member according to the invention is presented in claim 1. A delimbing apparatus with a feeding member according to the invention is also presented in claim 5.

A basic principle in the invention is to utilize existing actuators and to supplement them, if necessary, with simple integrated mechanisms, wherein it is not necessary to include more actuators and to control them.

Another principle is to change, primarily to reverse the effect of the same force of the actuator, for example the effect of the movement extending or contracting a cylinder. The result of the change is, for example, a closing movement instead of an opening movement, or vice versa. In other words, when the harvester head is in the delimbing position, the descending movement of the feed wheel is reversed to an ascending movement, or vice versa.

A particular principle is the sequence of transferring the different members of the harvester head to affect the function of said mechanism. The mechanism and the functional sequence affect the normal actuators of the harvester head in such a way that it is possible to open the feeding member at a sufficient distance from the tree trunk, the, grapple or the delimbing members. The advantages are the simplicity and reliability of the structure, an insignificant increase in the weight and the integration in the normal actuators. By means of the invention, the possibilities of using the normal actuators are increased. The modification of known harvester heads to comply with the invention is easy, and in one embodiment, it primarily requires a change in the position or mounting point of the actuator.

In the following description, the invention will be illustrated with reference to the appended drawings, in which:

Fig. 1 shows a partly reduced harvester head in which the invention is applied, as well as the initial stage of the transfer sequence,

Fig. 2 shows the reduced harvester head of Fig. 1 and the mid- stage of the transfer sequence,

Fig. 3 shows the harvester head of Fig. 1 in the loading position and the final stage of the transfer sequence, Fig. 4 shows the harvester head of Fig. 1 in the delimbing position,

Fig. 5 shows a detail of the harvester head of Fig. 1 and an embodiment of the invention, and

Fig. 6 shows another embodiment of the invention.

Figure 1 shows a delimbing apparatus 1 in a partially reduced manner, for the sake of clarity, illustrating the frame structure 2 which will be placed on top of the tree trunk to be manipulated and to which a mounting arm 4 with a U-shape is coupled by joints 5 and 6. In this embodiment, the feeding member 3 comprises a roll rotatable by means of a motor 7. In Fig. 1, the horizontal harvester head 1 is ready for the delimbing of the tree trunk. Normally, there are two mounting arms 4 and two feeding members 3 placed symmetrically on both sides of the tree trunk. The tree trunk is thus gripped on opposite sides, and simultaneously it is supported and pressed against the frame structure 1. The tree trunk is moved in its longitudinal direction, which is also the direction of the rotation axis X of the joints 5 and 6. It is also possible to arrange that the feeding member 3 is only supported by a mounting arm 4 with a single branch or a single arm and a single joint, as opposed to the U-structure of Fig. 1 with two branches and two joints. The reference numerals of Fig. 1 are also valid for the respective parts in the other drawings. An actuator 10 is coupled between the mounting arm 4 and the frame 2, in this case a cylinder to take care of the rotational position and the compressive force of the feeding member 3. The cylinder 10 is coupled to a torque arm 11 at a distance from the axis X, wherein it produces a torque to pivot the mounting arm 4.

The apparatus 1 also comprises a delimbing blade 12 whose rotation axis Y is substantially parallel to the rotation axis X. The delimbing blade 12 and its delimbing blade pair 8 are used to support and delimb the tree trunk. The properties of the apparatus 1 include that it can also be used to load one or more tree trunks, wherein the delimbing blades are used to grip the tree trunks on the ground or in a stack and to hoist them to a desired position. The apparatus 1 also comprises a mecha- nism 13 by which the feeding members 3 can be moved out of the way, wherein the feeding members 3 are not damaged during the loading, do not limit the opening of the delimbing members 12 nor prevent the gripping of the tree trunks to be supported by the delimbing members used as a grapple.

In the embodiment shown in the figures, the mechanism 13 is implemented by means of rotatable cams 14, 15, but it can also be implemented in another way. One principle of the mechanism 13 is that the position of the cylinder 10 controlling the position of the feeding member 3 is turned so that, depending on the position, an extension of the cylinder 10 effects either a closing movement of the feeding member 3 towards the tree trunk, against which it is pressed, or an opening movement of the feeding member 3 away from the tree trunk, wherein loading is possible. In this case, the position of the cylinder 10 can be changed to both sides of a so-called dead point, which effects a different function even though the cylinder 10 is extended in both cases. At the dead point, the value of the torque arm is zero. The dead point can be found by examining the positions of the torque arm 11 and the cyl- inder 10, particularly in relation to the rotation axis X. At the dead point, the orientation of the cylinder 10, which is transverse to the rotation axis X, is changed to another side of said rotation axis X, wherein the direction of rotation of the feeding member 3 is changed, even if the movement involved is the same linear movement extending (or con- tracting) the cylinder 10. The opening of the feeding member 3 presented in this description can also be implemented by means of a con- tractible cylinder. In this case, the torque arm 11 is placed in such a way that in the dead point, it is rotated 180° in relation to the position of Fig. 5. It may be necessary to modify the structure of the torque arm 11 and the joint 6 or to move the cylinder 10 to prevent collisions and to make space for the movement of the cylinder.

At one end and at its frame 16, the cylinder 10 is mounted to the frame 2 by means of a joint 19 (Fig. 5) which makes it possible to change the rotational position of the cylinder 10 around such a rotation axis Z which extends through said joint 19 and which is parallel to the rotation axis X. It should be mentioned that Fig. 5 only shows the necessary parts of the feeding member 4, wherein only the torque arm 11 is visible.

The cylinder 10 can be moved past the dead point (position A in Fig. 5) e.g. with another actuator 20, as sketched in Fig. 5, but its placement in the frame 2 may be difficult and may increase the weight of the delimbing apparatus 1.

According to one embodiment, no actuators or mechanisms will be needed to change the position of the cylinder 10. After the cylinder 10 has been sufficiently contracted, the feeding member 3 or a structure connected to it is pressed, for example, against the ground to exert a force to open the feeding member 3. The feeding member 3 and simultaneously the cylinder 10 move past the dead point (position A in Fig. 5), and the function effected by the extending movement is reversed. The cylinder 10 is returned to its original position (position C in Fig. 5) by means of gravity, if the cylinder 10 is first allowed to contract sufficiently.

According to an advantageous embodiment, the passing of the dead point is effected by fixed mechanical guides 14, 15 and by moving the delimbing blade 12 and the feeding member 3 according to a given sequence of movements to eliminate the actuators and the need to control them.

As shown in Fig. 1 , the apparatus 1 comprises a mounting arm 4 controlled by a cylinder actuator 10 and mounted to the frame 2 in a rotatable manner. The cylinder 10 is placed in such a way that the mounting arm 4 can be swung (see Fig. 5) to a first position (posi- tion C, or other positions corresponding to it), in which an extension of the cylinder 10 will effect the closing of the mounting arm 4, i.e. its movement towards the tree trunk. The mounting arm 4 can also be swung to a second position (position B, or other positions corresponding to it), in which an extension of the cylinder 10 will effect the opening of the mounting arm 4. In said positions, the cylinder 10 is also turned in different positions, wherein the same result can be obtained by forcing the cylinder 10 into the different positions, which, in turn, will effect a change in the position of the mounting arm 4, as long as e.g. the piston rod 17 of the cylinder 10 is sufficiently withdrawn. Thus, point 18, at which the piston rod 17 is connected by a joint to the mounting arm 4, is placed between the axis X and the point 19 where the cylinder frame 16 is mounted by means of the joint (cf. axis Z) (see Fig. 5). In a second embodiment, the axis X is between the corresponding point 18 and the mounting point of the cylinder frame 16, so that the cylinder 10 intersects the axis X.

In another embodiment of the invention, the position of the cylinder 10 is guided by a first cam member 14 rotatable with the mounting arm 4 around the rotation axis X, and a second cam member 15 rotatable with the delimbing blade 12 around the rotation axis Y. The cam members 14, 15 are placed so that, in a given position, they can support each other, wherein they are placed in a plane transverse to said axes X, Y. The cam members 14,. 15 are placed particularly so that the rotation of the second cam member 15 can force the first cam member 14 to rotate, provided that the position of the mounting arm 4 and the delimbing member 12 is suitable. As a result of the forcing, the cylinder 10 is moved past said dead point.

We shall now discuss the embodiment implemented with the cam members 14, 15 and the functional sequence relating to them. In the situation of Fig. 1, the cylinder 10 is above the dead point, and its extension effects the normal closing of the feeding member 3. The first cam 14 is rotated with the feeding member 3 and is, in this embodiment, placed above the second cam member 15. The second cam member 15 is rotated with the delimbing member 12. Next, the aim is to open the feeding member 3 as much as possible, wherein the delimbing apparatus 1 is used as a grapple. The delimbing member 12 is opened so that the cam member 15 is rotated up to a position in which the rotatable cam member 14 cannot collide with it. The piston rod 17 of the cylinder 10 of the feeding member 3 is withdrawn by contracting it, if necessary, down to its minimum dimension, wherein the cam member 14 can move under the cam member 15 to a position in which the cam member 15 of the closing delimbing member 12 can collide with it. Furthermore, the cam member 15 of the closing delimbing member 12 forces the cam member 14 to rotate further in the direction corresponding to the opening direction of the feeding member 3 as shown in Fig. 2. The opening of the feeding member 3 also forces the cylinder 10 to turn to a different position, and the cylinder 10 moves past the dead point; in other words, it is directed further downwards and under the axial line X (in Fig. 1 , it is directed further upwards and across the axial line X). Now, as the cylinder 10 is extended, the feeding member 4 is opened further, into the position of Fig. 3.

The return of the feeding member 3 to the position shown in Fig. 1 or Fig. 4 is effected by re-contracting the cylinder 10 and by opening the delimbing member 12 sufficiently so that the cam member 14 and 15 would not collide with each other. The cylinder 10 is moved past the dead point by the effect of gravity, because the torque caused by the mass of the feed wheel 3 tends to close the feeding member 4. Consequently, the point of the joint 18 of the piston rod 17 on one hand and the mass centre of the feeding member 3 on the other hand are placed on different sides of the rotation axis X. After this, it is possible to pro- ceed with the normal operations of felling and delimbing. The closing feeding member 3 can be received by the cam member 15 and closed in a controlled manner at the same time when the delimbing member 13 is opened from the position shown in Fig. 2.

According to one embodiment of the invention and Fig. 6, the feeding member 3 is not controlled by the actuator 10 but by a mechanism 21 which is, for example, a drawbar 23. The drawbar 23 is fixed between the point 18 and the joint 22 of the torque arm 11. In this case, the cylinder 10 is not rotated around the rotation axis Z, but the rotation can also be allowed. In Fig. 6, the rotation position Bb (or another corresponding position) of the mechanism corresponds to the position B of Fig. 5, wherein an extension of the cylinder 10 effects the opening of the feeding member. In the dead point, the drawbar 23 is in the position Aa and is oriented towards the rotation axis X. The fixed orientation of the cylinder 10 is not necessarily towards the rotation axis X. For the feeding of the tree trunks, the drawbar 23 is moved (rotated with respect to the point 18) to the position Cc (or other corresponding posi- tions), wherein an extension of the cylinder 10 effects the closing of the feeding member. The auxiliary cylinder 20 of Fig. 5 can now be coupled directly to the drawbar 23. The drawbar 23 and the torque arm 11 are even now simultaneously in the dead point (position Aa).

Instead of the drawbar 23, it is also possible to use other members or mechanisms which comprise said dead point or are otherwise effective between the feeding member 3 and the cylinder 10 so that the same movement of extension/contraction of the cylinder 10 effects the oppo- site function. It is primarily a question of coupling the torque arm 11 , i.e. the feeding member 3, and the cylinder 10 to each other and their position in relation to each other, or the position of the mechanism between them. The coupling between the feeding member 3 and the cylinder 10 must also include the feeding member 3 and the cylinder 10 itself, if a change in their position as well has an effect on the function, as in the case of Fig. 5, in which the cylinder is directly coupled to the torque arm 11. In the case of Fig. 6, the coupling includes at least the feeding member 4. In the mechanism, for example, a change in its state allows a change in the function, wherein different states corre- spond to different positions. The mechanism 13 can also be applied with the mechanism 21, wherein instead of the cylinder 10, for example the position of the drawbar 23 is changed (Cc-Aa-Bb-Aa-Cc).

The delimbing apparatus 1 is coupled to the end of a crane in the work- ing machine, wherein it comprises the necessary clamping and rotating members for rotating the frame 2 around a substantially vertical axis.

The frame is normally suspended by means of a swinging arm which is provided to rotate the frame around a substantially horizontal axis. The swinging arm is mounted to the frame by means of a rotating joint. The delimbing apparatus also comprises a curved first arm of the delimbing member and, as its pair, a second arm which is mounted to the frame by means of joints in a rotatable manner. The arms are provided with cutting edges or delimbing blades. The cutting member, particularly a chain saw driven by a cylinder and placed in a saw box, is also used for cutting the tree trunk into pieces of a fixed length. The delimbing members are closed around the trunk, and they are designed to be curved. The front part of the frame is normally also equipped with an integrated auxiliary delimbing member. The delimbing apparatus may also be equipped with grapple members for loading and transferring trunks. The grapple members comprise a pair of jaws placed on different sides of the tree trunk, wherein the feeding member may be placed inside the jaws, as shown in Fig. 1 , where it is between the upper delimbing blade 12 and the lower delimbing blade 9 (in the figure, the delimbing blade 9 is turned underneath the frame 2).

In the above-presented description, the invention has been illustrated by means of some examples, but the invention can also be applied within the scope of the appended claims. Furthermore, it is obvious that both feeding members of the delimbing apparatus are controlled by devices according to the invention. The cam members can also be placed in such a way that they are on the side of the upper delimbing blade, wherein the lower delimbing blade may be totally eliminated.

Even in that case, the operation corresponds to that described above.

The delimbing blades may also constitute a U-shaped structure, inside which the feeding member and the mechanism 13 are placed. The rest of the structure of the delimbing members, the actuators and the members used may vary in a way known as such.

Claims

Claims:

1. A delimbing apparatus with a feeding member arranged to feed tree trunks through the delimbing apparatus (1) and mounted to the delimbing apparatus (1) in a rotatable manner and arranged to close to a position in which it is intended to be placed against a tree trunk in the delimbing apparatus as well as to open to a position which makes it possible to use the delimbing apparatus for loading one or more tree trunks, wherein the delimbing apparatus also comprises a cylinder actuator (10) arranged to open and close said feeding member (3), characterized in that a coupling (11 , 21) is provided between said cylinder actuator (10) and said feeding member (3), which coupling can be transferred to a position (C, Cc), in which the movement of extending or contracting the cylinder actuator (10) effects the closing of the feeding member (3), and that said coupling (21) can also be transferred to a position (B, Bb), in which the same movement of extending or contracting the cylinder actuator (10) effects the opening of the feeding member. (3).

2. The delimbing apparatus according to claim 1 , characterized in that said cylinder actuator (10) is coupled to said feeding member (3) by means of a torque arm (11) changing the position, and that the position of said cylinder actuator (10) can also be turned to different positions.

3. The delimbing apparatus according to claim 1 , characterized in that said cylinder actuator (10) is coupled to said feeding member (3) by means of a mechanism (11 , 21) changing the position, and that the position of said cylinder actuator (10) remains unchanged.

4. The delimbing apparatus according to any of the claims 1 to 3, characterized in that the coupling comprises a dead point, said positions being placed on different sides of the dead point, wherein the passing of the dead point is arranged to effect a change in the direction of rotation of the feeding member (3) even if it was the same movement of extending or contracting the cylinder actuator (10).

5. A delimbing apparatus with a feeding member arranged to feed tree trunks through the delimbing apparatus (1) and mounted to the delimbing apparatus (1) in a rotatable manner and arranged to close to a position in which it is intended to be placed against a tree trunk in the delimbing apparatus as well as to open to a position which makes it possible to use the delimbing apparatus for loading one or more tree trunks, wherein the delimbing apparatus also comprises a cylinder actuator (10) arranged to open and close said feeding member (3), characterized in that said cylinder actuator (10) can be turned to a position, in which the movement of extending or contracting the cylinder actuator (10) effects the closing of the feeding member (3), and that said cylinder actuator (10) can also be turned to a position, in which the same movement of extending or contracting the cylinder actuator (10) effects the opening of the feeding member (3).

6. The delimbing apparatus according to claim 5, characterized in that said positions of the cylinder actuator (10) are on opposite sides of the position corresponding to the dead point of the cylinder actuator (10), wherein the dead point corresponds to the position in which the cylinder actuator (10) is contracted or extended.

7. The delimbing apparatus according to claim 5 or 6, characterized in that the delimbing apparatus (1) also comprises a second actuator which is arranged to turn the cylinder actuator (10) into different posi- tions.

8. The delimbing apparatus according to any of the claims 5 to 7, characterized in that the delimbing apparatus (1) comprises a rotatable delimbing member (12) which is arranged to rotate around a first rotation axis (Y) in relation to the delimbing apparatus (1), a first cam member (15) rotatable with said delimbing member (12), a second cam member (14) rotatable with said feeding member (3), wherein the first cam member (15) is arranged to force the second cam member (14) to rotate in a direction which simultaneously turns the feeding member (3) which, in turn, effects the turning of the cylinder actuator (10) into a different position.

9. The delimbing apparatus according to claim 8, characterized in that before said forcing, the delimbing member (12) can be turned together with the first cam member (15) into the open position.

10. The delimbing apparatus according to claim 9, characterized in that before said forcing and after the opening of the delimbing member (12), the cylinder actuator (10) can be turned to a position, in which the cylinder actuator (10) is contracted and oriented towards the rotation axis (X) of the feeding member (3).

11. The delimbing apparatus according to claim 9, characterized in that before said forcing and after the opening of the delimbing member (12), the cylinder actuator (10) can be turned to a position, in which the cylinder actuator (10) is extended and intersects with the rotation axis (X) of the feeding member (3).

12. The delimbing apparatus according to any of the claims 8 to 11 , characterized in that during said forcing, the delimbing member (12) can be turned together with the first cam member (15) into the closed position.

13. The delimbing apparatus according to any of the claims 8 to 12, characterized in that after said forcing, the extension of the cylinder actuator (10) is arranged to effect the opening of the feeding member (3).

14. The delimbing apparatus according to any of the claims 5 to 13, characterized in that said cam members (14, 15) are placed around the same rotation axes (X, Y) as the delimbing member (12) and the feeding member, wherein each cam member (14, 15) comprises a cam extending at a distance from the rotation axis and farther away from the rest of the cam member, wherein the cam members (14, 15) are also arranged to rotate in a common plane which is perpendicular to said rotation axes (X, Y).

15. The delimbing apparatus according to claim 5 or 6, characterized in that the cylinder actuator (10) is arranged to turn to a different posi- tion by means of the force exerted by pressing the feeding member (3) against the ground.

16. The delimbing apparatus according to any of the claims 5 to 15, characterized in that the cylinder actuator (10) is arranged to return to its original position by means of the force exerted by gravity closing the feeding member (3).