Patent Application
20130299046
The object of the invention is a method as defined in the preamble of claim 1 and an apparatus as defined in the preamble of claim 8 for handling a tree.
The solution according to the invention is particularly well suited to removing trees causing a nuisance, such as e.g. to delimbing trees that have fallen onto electric lines and to truncating and removing trees from on top of powered electric lines. The solution according to the invention is also suited to the preventive maintenance, servicing and upkeep of the corridors of electric lines, such as to e.g. preventive clearing, in which trees that are above a powered electric line, too close to an electric line, possibly causing a disruption in electricity distribution, are removed using safe working methods. The invention is also well suited e.g. to the removal of trees growing in residential areas or in other cramped places. In addition, the solution according to the invention can be utilized also for the servicing and disassembly of electric lines e.g. such that the apparatus according to the invention climbs an electric pillar instead of a tree and disassembles the electric lines supported on the pillar.
Trees can fall onto electric lines e.g. during violent storms or also from the weight of a snow load. Trees that have fallen onto powered electric lines have, according to prior art, been removed such that the current is disconnected from the electric lines of the damaged section by isolating the electric line from the mains grid and, in addition, the damaged section of the electric line is also earthed. Earthing must be performed because, among other reasons, even though the damaged section was isolated from the mains grid, some small power station that is connected to the electric line can still supply current to the electric line. Isolating the damaged section from the mains grid and earthing it is a very laborious and time-consuming procedure, so that it is sometimes left undone. In this case, however, the people participating in repairing the damaged section are placed in life-threatening danger, because an electric shock received from a powered electric line is potentially lethal. After isolating the damaged section of the electric line from the mains grid and earthing it, a group of lumberjacks go and remove the tree by hand with the aid of motorized saws, delimbing shears and possibly other special tools. One problem, among others, in this type of conventional solution is that when disconnecting the current from powered electric lines, many households and farms, and other institutions that need electricity, are left without electricity. Disconnection of the current can cause an electricity outage to thousands of these types of locations. Electricity outages cause costs for electricity companies and trouble as well as costs and safety risks for people and, more particularly in agriculture, for animals. Another problem in the aforementioned conventional method is that the work is extremely dangerous for other reasons than the possibility of electric shock and in the work accidents can easily happen to the lumberjacks who remove trees that have fallen onto electric lines.
It is known in the art that trees growing in residential areas and in other cramped places are felled e.g. such that the person performing the felling climbs the tree and cuts the tree in stages starting from the top. A problem in this solution is, however, that the work is rather slow and also extremely dangerous. In addition, generally a second person is needed, who assists the person in the tree and guides the cut branches and pieces of trunk safely onto the ground. Finnish patent number FI115501 (B), which corresponds to U.S. Pat. No. 7,591,292 (B2), presents a delimbing apparatus and a method for delimbing erect trees. The solution comprises a frame part to be fixed to the end of an articulated boom of a power tool, such as of a forestry machine, and a separate delimbing head connected to the frame part, which delimbing head ascends along the trunk of a tree and delimbs the tree and also, if necessary, cuts the trunk starting from the top. The apparatus, with its gear wheels and accordion-type tightening device, is extremely complex and, owing to its many parts, also susceptible to failure. Another problem is that the cut branches and parts of the trunk can fall directly onto the frame part around the trunk of the tree below and can damage it. The publication also does not mention anything about removing trees that have fallen on top of electric lines. This is understandable because the apparatus is not at all suited to this type of work. The frame part and the delimbing head can only be put around the trunk of a vertical tree, not around a fallen and inclined trunk. The Finnish patent only mentions with regard to the fixing of the frame part to the boom system of a forestry machine that the frame part is fixed to the boom system with a swivel joint that allows the frame part to be turned in the desired direction, which makes it easier to delimb trees standing close by each other side by side and one behind the other. No mention is made of inclination. In addition, the patent does not present a solution with which a fallen tree can be pulled upright.
German patent publication no. DE3702760 (A1) also presents a delimbing and debarking device that ascends an erect tree. The part of the device ascending the tree comprises motor-controlled means of the caterpillar-track type, which means rest on the surface of the tree and when moving simultaneously move the delimbing head in the vertical direction. Also this publication does not mention anything about removing trees that have fallen on top of electric lines, and also this device is not even suited to such work. In addition, also this publication does not present a solution with which a tree that has fallen onto electric lines could be pulled upright.
One aim of the present invention is to eliminate the aforementioned drawbacks and also to achieve an inexpensive, simple, fast and safe method and apparatus for handling tree. In addition, an aim of the invention is to achieve a method and an apparatus, by the aid of which trees that have fallen onto electric lines or into otherwise awkward places, as well as trees standing in cramped locations, can be delimbed, cut and removed easily and safely. The method according to the invention is characterized by what is presented in the characterization part of claim 1. Correspondingly, the appliance according to the invention is characterized by what is disclosed in the characterization part of claim 8. Other embodiments of the invention are characterized by what is disclosed in the other claims.
One advantage of the solution according to the invention is that by means of it trees that have fallen onto electric lines can be removed without disconnecting the current from powered electric lines. Another advantage also is that the method is safe, because the work can be done by remote control, in which case people do not need to be too close to an electric line. Another advantage is that a tree that has fallen onto electric lines can be lifted off the lines before cutting the tree, in which case the lines are not damaged in connection with removal of the tree, and also the tree no longer conducts electricity to earth. Yet another advantage is that the apparatus according to the invention is light, as a result of which it can, if necessary, be taken to a location by hand by carrying it, in which case also trees causing a nuisance in awkward locations can be removed. Another advantage is also that by means of the method and apparatus according to the invention trees growing in residential areas or in other cramped locations can be quickly and safely removed.
In the following the invention will be described in more detail by the aid of one example of its embodiment with reference to the attached drawings, wherein
The crosscut device 1 is connected to a hydraulic powerpack 2 via hydraulic hoses 3. In addition, a current source 4, such as e.g. a generator and/or battery pack, is fitted in connection with the hydraulic powerpack 2, which current source 4 is connected with electric cables 5 to the crosscut device 1. The parts of the crosscut device 1 needing electricity along the electric cables 5, such as the control system, the working lights and a possible video camera, receive the necessary control current and operating current from the current source 4. The transport device and the crosscut device 1 are controlled by remote control with a control unit 6 belonging to the arrangement. The construction and the different parts of the crosscut device 1 are presented in more detail in the figures below.
The crosscut device 1 comprises a fixing point, to which a steel rope 7 or corresponding rope acting as a pulling rope is connected, which rope the crosscut device 1 takes along with it upwards along the trunk. When the crosscut device 1 has climbed to high enough, the crosscut device 1 is firmly locked around the trunk of the tree and the tree is pulled by means of the rope 7 and some suitable pulling device, such as a block and tackle 8, upright and off the electric line. The rope 7 is not in this case detached from the fixing point, such as from the pulling lug or pulling hook, on the crosscut device. During the pulling the block and tackle 8 is fixed e.g. to a growing tree 9 that will withstand the stress caused by the pulling. After this the top part of the trunk of the tree to be removed is cut off by means of the chain saw comprised in the crosscut device 1. If necessary, the crosscut device 1 cuts the trunk of the tree into parts of suitable dimension as it descends, but the final felling and truncating can also be performed later.
The portable control unit 6 comprises at least a radio unit provided with a radio transmitter, and controllers with which the functions of the crosscut device 1, of the transport device and of the hydraulic powerpack 2 are controlled by remote control. In addition, the control unit 6 comprises a display, from which a user of the control unit 6 can monitor, inter alia, the video image filmed by the video cameras on the transport device and on the crosscut device 1. By monitoring the image of the video camera of the transport device, a user of the control unit 6 is able to control the crosscut device 1 to the tree by the aid of the transport device and to fix the crosscut device 1 to the trunk of the tree by remote control. By monitoring the image of the camera of the crosscut device 1, it is possible in turn to monitor the progress of the crosscut device on the trunk of a tree.
The lower grippers 16 are hinged on the lower cylindrical support arms 17, which lower grippers consist of at least a hinge arm 16a pointing backwards from the crosscut device 1 and of an inward curving gripper arm 16b pointing forwards from the crosscut device 1, which gripper arm is pressed around the trunk of the tree. There are two lower grippers 16 opposite each other but at a different height with respect to each other in relation to the frame 10 such that in the closed position the gripper arms 16b opposite each other overlap as viewed from above in relation to each other. A power means 18, such as a hydraulic cylinder, achieving a linear movement connects the hinge arms 16a of the lower grippers 16, which power means is fitted by means of a remote-controlled control unit 6 to move the curved gripper arms 16b of the grippers 16 towards each other and away from each other, i.e. at the same time to close and to open the curved gripper arms 16b forming a space.
Correspondingly, the upper grippers 20 are hinged on the upper cylindrical support arms 21, which grippers are essentially similar in their shape, structure and articulation to the lower grippers 16. A power means 22, which is not visible in
The top edge of the curved gripper arms of the upper grippers 20 contains a shearing blade 20a, by means of which the crosscut device 1 cuts off branches of a tree that are in its way when it climbs upwards. In addition, the top part of the crosscut device 1 comprises a third curved cutting blade 23, the top edge of which comprises a similar shearing blade as in the top edge of the curved gripper arms of the grippers 20. The cutting blade 23 is fixed e.g. to the transverse top support 12a of the frame 10 in such a position that together with the shearing blades 20a of the gripper arms 20 the shearing blade of the cutting blade 23 forms an essentially at least full circle around the trunk of a tree, in which case the shearing blades of the tree are able to cut off branches of the tree leaving in all directions when the crosscut device 1 climbs upwards along the tree.
The top part of the crosscut device 1 further comprises an articulated crosscut unit 24, which comprises at least a hydraulic saw 25, such as a chainsaw, acting as a crosscut means, and actuators, such as hydraulic cylinders 25a and 27 as well as a rotating shaft 26 and lever arm 26a, turning the chainsaw 25 into the transport position and into various sawing positions. The crosscut unit 24 is intended for cutting the trunk of the tree, but if necessary also thicker branches can be cut with it.
In addition, at the rear of the crosscut device 1 is a pulling lug 30 or corresponding fixed to a supportive point, e.g. to the upper transverse rear support 10a, to which pulling lug the steel rope 7 functioning as a pulling rope is fixed for taking an end of the rope up into the tree for pulling the tree upright when the crosscut device 1 has finished the tree ready for lifting upright.
In
In
All the hydraulic actuators presented above, or at least a part of them, can also be electrically-operated actuators, such as e.g. spindle motors, and instead of a hydraulic powerpack 2 and/or current source 4 on the ground the crosscut device 1 can be provided with its own chargeable current source giving current to all the actuators of the crosscut device 1, such as with one or more accumulators, which are fixed in connection with the crosscut device 1 to travel along with the crosscut device 1 into a tree. In this way the crosscut device 1 can operate under remote control as a wireless and hoseless unit.
The crosscut device 1 comprises at least a frame 32 comprising a bottom part 35 and a top part 36 as well as, between the top part and the bottom part, guides 34 in the direction of the climbing movement and descending movement. In addition, the crosscut device 1 comprises a spindle motor functioning as a power means 33, by the aid of which the distance between the bottom part 35 and the top part 36 can be changed in the climbing phase and descending phase forming the stepped, i.e. cyclical, movement of the crosscut device 1 in essentially the same manner as has already been explained. The distance between the bottom part and top part is controlled in the climbing phase and descending phase e.g. by means of position sensors suited to the purpose. The climbing movement and descending movement are essentially similar to what has been described above.
Carrying handles 37 are also fixed to the frame 32 of the crosscut device 1, by means of which handles the lightweight-structured device can be transported by carrying, and an articulated, multiple-part boom structure 32a, which functions in the manner of a robot arm. At the free end of the boom structure 32a is a mounting base 32b for the tools, such as a chainsaw 25 or some other necessary tool, such as a nut opener, metal cutting tool or corresponding, to be used with the crosscut device 1. In addition, the top part of the crosscut device 1 comprises locking means 41, such as grapple tongs, by means of which the crosscut device 1 can be firmly fixed to the tree to be handled e.g. for pulling the tree upright by means of a rope 7 and a pulling device 8. The grapple tongs 41 operate by the aid of an actuator, e.g. a spindle motor, intended for them and there are preferably means, such as a fastening ring or a pulling hook or corresponding, in connection with the grapple tongs 41 for fixing a rope 7 to the crosscut device 1.
The bottom part 35 of the crosscut device 1 comprises two gripper arms 38a that are essentially similar to each other but that move in an opposite direction to each other and the top part 36 correspondingly comprises two gripper arms 38b that are essentially similar to each other but that move in an opposite direction to each other for enabling the climbing movement and descending movement of the crosscut device 1. All the gripper arms 38a and 38b comprise a supporting stem part 40, which is fitted to the guides 35b, 36b in the bottom part and in the top part, which guides are disposed at an essentially orthogonal direction to the direction of the climbing movement and descending movement of the crosscut device 1, i.e. in practice often horizontal. The bottom part 35 of the frame 32 comprises a spindle motor functioning as an actuator 35a for moving the gripper arms 38a towards each other and the top part 36 of the frame 32 comprises a spindle motor functioning as an actuator 36a for moving the gripper arms 38b towards each other. At the free end of the gripper arms 38a, 38b is a gripper 39, the inside surface of which is curved and roughened so that the grip of the gripper 39 on the tree or pillar would be as firm as possible.
The crosscut device 1 according to
The crosscut device 1 according to
The crosscut device 1 according to
In the crosscut device 1 according to
With the method according to the invention a tree causing a nuisance is removed e.g. as follows: the crosscut device 1 is brought to the tree to be removed either by carrying with manpower or with a transport device suited to the purpose and is placed around the trunk of the tree from the side of the trunk by pushing the crosscut device 1 with the grippers 16, 20, 39 to the front, when the grippers 16, 20, 39 are in the open position, onto the trunk of the tree and after this by locking at least the lower grippers 16, 39 around the trunk of the tree. After this a command to climb the tree is given with the remote controller 6 to the crosscut device 1, in which case the crosscut device 1 climbs the tree according to a defined control logic and operating logic such that at first the upper grippers 20, 39 are loosened from around the trunk of the tree, if they were earlier locked around the trunk.
After this the length of the frame 10, 32 of the crosscut device is increased by means of the telescopic support arms 13 and 14 as well as by means of the hydraulic cylinders 31 or the spindle motor 33 acting as the power means, in which case the distance between the upper grippers 20, 39 and the lower grippers 16, 39 increases. When the distance is at its maximum or otherwise e.g. in the correct spot determined by the sensors 13a, 14a, the upper grippers 20, 39 are locked around the trunk of the tree and the lower grippers 16, 39 are loosened from around the trunk, after which the length of the frame 10, 32 of the crosscut device is shortened by means of the telescopic support arms 13 and 14 as well as by means of the hydraulic cylinders 31 or the spindle motor 33, in which case the distance between the upper grippers 20, 39 and the lower grippers 16, 39 decreases. When the distance is at its permitted minimum or otherwise e.g. in the correct spot determined by the sensors 13a, 14a, the lower grippers 20, 39 are locked around the trunk of the tree and the upper grippers 16, 39 are loosened from around the trunk, and the climbing is continued in this way step-by-step and at the same time branches in the way are cut off by means of the shearing blades 20a and the cutting blade 23 or by means of the chainsaw 25, until the desired height is reached.
When the crosscut device 1 is at the desired height, the top of the upright tree is cut off by means of the chainsaw 25 and the top is allowed to drop to the root of the tree. After this a command is given with the remote controller 6 to the crosscut device 1 to come down from the tree and, if necessary, parts of the desired dimension are cut from the trunk of the tree with the chainsaw 25 when coming down, which parts are allowed also to drop to the root of the tree.
The procedure described above is good to use e.g. for removing trees in cramped places in residential areas. For the removal of a tree that has fallen at an inclined angle onto electric lines, it is instead good to use a slightly different method according to the invention. Placement of the crosscut device 1 around the trunk of the tree, climbing the tree and the cutting off of branches is performed in the same way as described earlier. The difference is now that for pulling the tree upright a steel rope 7, or corresponding rope, is fixed to the pulling hook 30 on the crosscut device when the crosscut device 1 is still at the bottom, the free end of which rope is connected e.g. to a block and tackle 8, which is further fixed to some supporting point, e.g. to a growing and sufficiently strong tree 9. The crosscut device 1 when it climbs takes the rope 7 into the tree and when the crosscut device 1 has ascended to the desired height, the tree that has fallen at an angle onto an electric line is pulled upright by means of the block and tackle 8 and the rope 7, after which the top of the tree is cut off by means of the chainsaw 25. After this the crosscut device 1 is ordered down, as stated earlier. If so desired, the trunk of the tree is cut in connection with the descent into shorter parts.
In the method the crosscut device 1 is controlled by means of the remote-control device 6 using as an aid the video image of a video camera on the crosscut device 1 and, if necessary, a working light, as explained above.
It is obvious to the person skilled in the art that the invention is not limited solely to the example described above, but that it may be varied within the scope of the claims presented below. Thus, for example, the phases of the method can be different and in a different sequence to what is presented above.
It is further obvious to the person skilled in the art that the apparatus can be structurally different to what is described above.
It is also obvious to the person skilled in the art that the apparatus can be configured to climb along all pillar-like structures and not just along trees. Thus, for example, the apparatus can be configured to climb along e.g. electric pillars or lighting pillars or e.g. along various beam structures, and the apparatus can take along with it various tools for various procedures to be performed on a pillar.
| Number | Date | Country | Kind |
|---|---|---|---|
| 20106389 | Dec 2010 | FI | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/FI11/51146 | 12/21/2011 | WO | 00 | 8/2/2013 |
