The instant application should be granted the priority date of Jan. 14, 2005, the filing date of the corresponding German patent application 102 005 001 843.2.
The present invention relates to a carrying system for an implement, such as a pole pruner, a palm cutter, a coffee harvester or the like, and a method for cutting a tree with a pole pruner.
DE 25 27 295 A1 discloses fixing a hand tool in position on a support structure that is carried on the back of an operator. The hand tool is connected with the support structure by a chain that is fixed on the hand tool.
With an implement such as a pole pruner, a coffee harvester, a palm cutter, or the like, the guide rod must be rotatable about its longitudinal axis during operation of the implement. However, by fixedly connecting the implement with a carrying system in the region of the center of gravity of the implement, a rotation of the implement about the longitudinal axis of the guide rod is no longer possible. In order to be able to operate at different heights, the guide rod of the implement is more or less inclined during operation. With a fixed arrangement of the guide rod on a carrying system, it is necessary to apply more or less force for the inclination depending on the desired height of operation. To thin out or clear woods, and at the same time to prevent wild growth on tree stumps, it is known to top or lop trees at a prescribed height.
It is an object of the present invention to provide a carrying system for an implement that permits a good operation of the implement without fatigue. A further object of the invention is to provide a method for cutting trees that can be easily carried out.
These and other objects and advantages of the present invention will appear more clearly from the following specification in conjunction with the accompanying schematic drawings, in which:
The inventive carrying system for an implement comprises a carrying arm and a receiving means held on the carrying arm for receiving the guide rod of an implement, wherein in a first state the receiving means is adapted to fix the guide rod in a longitudinal direction thereof, and wherein in a second state the receiving means is displaceable in the longitudinal direction of the guide rod. The method for cutting trees includes the steps of using a pole pruner that is held on a carrying system in the region of its center of gravity, and topping the tree at a prescribed height by cutting all the way around.
Due to the fact that the receiving means fixes the guide rod in a first state, and in a second state can be shifted or displaced in the longitudinal direction of the guide rod, the position of the receiving means on the guide rod can be adapted to the respective operating height. This facilitates working with the implement, and the force that the operator has to exert is reduced, so that a fatigue-free operation is possible with the implement.
It is provided that the receiving means fixes the guide rod of the implement if the weight of the implement loads the carrying arm, and that the receiving means is displaceable relative to the guide rod when the load is relieved. Since the receiving means fixes the guide rod when the weight of the pole pruner is suspended on the carrying arm, a fixing of the receiving means can be achieved merely by releasing the pole pruner. For the release, it is merely necessary to raise the pole pruner. The fixation via a receiving means can also easily be added to existing implements, since no special devices are necessary on the pole pruner itself.
The receiving means can include a connection element that bends easily and is held on the carrying arm, whereby the connection element fixes the guide rod in the connection element during tension, and when the tension is released can be displaced along the guide rod. The fixing of the guide rod by means of a connection element that bends easily permits a rotation of the pole pruner along the longitudinal axis of the guide rod during operation of the pole pruner. The displacement or shifting of the receiving means on the guide rod is easily possible by relieving the load on the connection element and shifting the receiving means. The receiving means with the connection element has a simple construction and a low weight, so that it can be easily manufactured.
Both ends of the connection element are advantageously fixed in position on the carrying arm. By fixing the ends of the connection element on the carrying arm, the height of the receiving means, and hence the height at which the pole pruner is held, can easily be fixed. However, it would also be possible for the connection element to be fixed in position on the carrying arm by means of an adjustment device. By suitable selection of an adjustment device, a rapid and simple adaptation of the distance of the receiving means from the carrying arm is possible. The connection element is advantageously a cable that is held on the guide rod by a Prusik knot. This knot ensures a good fixation of the receiving means on the guide rod when tension exists in the cable. Upon release of the cable, this knot is easily displaceable on the guide rod. To ensure a reliable loosening of the receiving means from the guide rod upon relief of the load of the cable, a guide means can be disposed between the cable and the guide rod, with this guide means being resiliently elastic in a radially upward direction. The resilient elasticity ensures the loosening of the knot. The guide means is advantageously essentially cylindrical, and has a slot that extends in the longitudinal direction of the guide means. In this way, a simple configuration of the guide means can be achieved accompanied by good spring characteristics. The ends of the guide means that are disposed in the longitudinal direction are expediently provided with a collar that faces outwardly from the guide rod. The collar can be easily monolithically produced with the guide means, and in a straightforward manner ensures that the cable cannot slip from the guide means during operation.
The receiving means can have a housing that surrounds that portion of the connection element that is disposed in the region of the guide rod. In this way, it is possible to protect the connection element from dirt and weather influences. The housing is advantageously essentially cylindrical. To prevent dirt from penetrating into the housing, a sealing means is provided between the housing and the guide rod of the pole pruner. The sealing means is advantageously made of felt, thereby achieving a good sealing effect. At the same time, felt has good antifriction properties, so that the housing can easily be shifted on the guide rod.
The receiving means advantageously has a mounting support, whereby a portion of the connection element across from the mounting support is disposed on the guide rod and presses the guide rod against the mounting support. In so doing, the connection element effects a fixation of the guide rod in the mounting support. As long as the weight of the implement presses on the mounting support, the connection element is tensioned and presses the guide rod into the mounting support. When the connection element is relieved by raising the implement, the force of the connection element upon the guide rod is reduced, and the mounting support can be shifted on the guide rod. Both ends of the portion of the connection element are advantageously held on the mounting support, whereby at least one end of the portion is held on the mounting support so as to be movable in its longitudinal direction. This results in a simple construction of the receiving means. The movable fixation of one end of the portion ensures that when the connection element is relieved, the tension in the portion that presses the guide rod into the mounting support is relaxed. The receiving means is expediently provided with an actuating means for loosening the connection element, whereby the actuating means acts upon the movable end of the portion of the connection element. As a result, the loosening of the portion can be actively assisted by the operator. A straightforward configuration is provided if the movable end is held on the mounting support by a loop. It can be advantageous for the portion to rest against a guide means of the receiving means. The connection element is advantageously a strap, which ensures a good introduction of force into the guide rod, and which, due to its small thickness, leads to a small overall size of the receiving means.
The receiving means can be fixed in position on the guide rod via a releasable fixing means. The fixing means is advantageously provided with a clamping lever that holds the receiving means against the guide rod. The clamping lever is in particular spring-mounted, thus ensuring a reliable holding of the receiving means on the guide rod. The clamping lever is advantageously provided with an actuating means for releasing the clamping action. The clamping lever ensures a simple operation, and permits an easy shifting of the receiving means on the guide rod.
The carrying system is expediently provided with a back support. The forces absorbed by the carrying arm can be conveyed directly to the shoulders and hips of the operator via the back support. This makes an ergonomic operation possible. The carrying system can also include a stomach support. The carrying arm is advantageously adjustably held on the back or stomach support, and the carrying system has at least one marking that characterizes a prescribed position of the carrying arm on the support. The marking enables a simple and rapid adjustment of the position of the carrying arm on the support. The marking advantageously correlates with a garment size so that the operator, on the basis of his or her garment size, can readily undertake the adjustment that fits him or her.
Pursuant to a method for cutting trees with a pole pruner that is held on a carrying system in the region of its center of gravity, the tree can be topped at a prescribed height by cutting all the way around.
The cutting at a prescribed height can be carried out in a simple manner with a pole pruner that is held on a carrying system in the region of its center of gravity. Due to the fact that the pole pruner is held in a region of its center of gravity, the guide rod is disposed approximately horizontally or is inclined only slightly relative to the horizontal. As a result, the guide bar of the pole pruner is disposed at a height that is favorable for topping trees. As a result of the fixation of the pole pruner on a carrying system, it is thus possible to carry out a cutting all the way around at a prescribed height in a simple manner.
The tree is advantageously topped at a height of 1.0 m to 1.8 m.
Further specific features of the present application will be described in detail subsequently.
Referring now to the drawings in detail,
The carrying arm 15 is angled off and extends over the shoulder of the operator 16 to the front of the operator. The carrying arm 15 can also extend over the head of the operator 16. The two ends 43 and 44 of a cable or cord 14 of a receiving means 13 are secured to that end 11 of the carrying arm 15 that extends to the front of the operator 16. The receiving means 13 is mounted on a guide rod 6 of the pole pruner 1 in the region of the center of gravity 47 of the pole pruner. Secured to one end of the guide rod 6 is a housing 2 in which is disposed a drive motor, in particular an internal combustion engine, that drives a saw chain that is not shown in
In the embodiment shown in
In
As can be seen from the exploded view of
The cable 14 is looped about the guide means 40 via a Prusik knot. In so doing, the cable 14 is looped nearly four times about the guide means 40. An outer loop 54 and an adjacent inner loop 55 extend in the same direction. Similarly, an inner loop 56 and an outer loop 57 extend in the same direction relative to one another and opposite to the loops 54 and 55. The ends 43 and 44 of the two inner loops 55 and 56 lead to the carrying arm 25 and are guided through a loop 58 formed by the interconnected outer loops 54 and 57. When there is tension in the cable 14, the Prusik knot pulls together, and the loop 58 fixes the cable 14. When the cable 14 is relaxed, the guide means 40 presses the Prusik knot open. As a result, the receiving means 13 can be shifted on the guide rod 6. It should be noted that also without the guide means 40 the Prusik knot can be shifted on the guide rod 6 in the relaxed state.
Instead of a Prusik knot, other knots could also be used. A mere looping around the guide rod can be advantageous. The receiving means 13 can also be fixed to the guide rod 6 by other means. The cable 14 can be elastic.
The carrying systems 48 and 49 can advantageously be used for topping or lopping trees. For this purpose, the pole pruner 1 is secured in position 47, on the carrying system 48 or 49 in the region of its center of gravity 47. As a result, the guide rod 6 is disposed approximately horizontally, or is inclined slightly relative to the horizontal. Due to the horizontal position, or the aforementioned inclination, of the guide rod, the height of the guide bar 8 above the ground is prescribed, and can be easily kept constant by the operator 16. To top a tree, the operator carries out a cutting of the tree all the way around with the pole pruner 1 that is disposed on the carrying system 48, 49. In this connection, the tree is advantageously topped at a height of about 1.0 m to about 1.8 m. A cut at a height of about 1.5 m is particularly advantageous. The topping of the tree causes it to die away. The topping at a prescribed height can prevent wild growth, which can occur when cutting close to the ground.
When a guide rod 6 is disposed in the mounting support 65, the portion 69 of the strap 64 presses the guide rod 6 into the mounting support 65 due to the implement's own weight. When the strap 64 is relaxed, in other words when the implement is raised, the portion 69 of the strap 64 is loosened, so that the guide rod 6 can be shifted in the receiving means 63. Loosening of the strap 64 can be enhanced by the operator by actuating the gripping means 67 and pressing on the mounting support 65. As shown in
A further embodiment is shown in
In the embodiment shown in
The receiving means 93 shown in
To enable a good adaptation of the height of the receiving means 63, the carrying system is provided with an adjustment device 60. The operator 16 shown in
The specification incorporates by reference the disclosure of German priority document 10 2005 001 843.2 filed Jan. 14, 2005.
The present invention is, of course, in no way restricted to the specific disclosure of the specification and drawings, but also encompasses any modifications within the scope of the appended claims.
Number | Date | Country | Kind |
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10 2005 001 843.2 | Jan 2005 | DE | national |