Cutter device for excavator or backhoe assembly
Technical field The present invention relates to a cutter device for an excavator or a backhoe assembly in accordance with the preamble of claim 1. More specifically, it relates to such an attachment which is intended to be mounted to a Swingotilt® and a grapple module integrated therewith. The grapple module, in cooperation with the device of Swingotilt® type integrated therewith, is capable of firmly gripping brushwood and smaller trees irrespective of growth direction, whereupon the cutter device, while the vegetation intended to be cut is held firmly, is capable of cutting it in an arbitrary manner, for example close to the roots. Background
Different types of clearing occur in various contexts. In many respects, this is a result of the uncontrollable force of nature and its desire to take back land conquered by man. Slowly, buts steadily nature takes over land that is not used all the time. For obvious reasons, there are for example forest roads which might not be used more than very infrequently and then maybe for timber forwarding. In between this, such roads might be used only as routes for wildlife and hikers. When there is a desire to create new or to clear previously existing, however not frequently used roads, a need arises to be able to carry out such work in an economically defensible way. To call in forwarder machines for such purposes cannot be defended economically, and furthermore, if the ground is waterlogged, cannot be done without causing great damages to the ground in many cases, unless the ground is frozen, something which will never happen in certain parts of the world. This as a natural consequence of the fact that forwarder machines are heavy machines. In addition, they are expensive to operate. For this reason, amongst others, it has been found that there has been a great need for a solution to the problems associated with being able to clear roads through
overgrown or previously uncleared terrain in a flexible and economically defensible way. It has been found that using excavators or backhoe assemblies might be one such possibility. However, due to the lack of equipment suitable for the purpose this has not been possible, but instead it has been necessary, if using forwarder machines has not been an option, to either clear manually or to use several different machines to be able to achieve an acceptable result, both in terms of clearing and economically. In connection with secret testing of a prototype solution, a device of the type defined in accordance with the invention has proved to be very efficient.
Brief summary of the invention
Therefore, the purpose of the present invention has been to try to find and show a solution to how a versatile machine of excavator or backhoe type can be used for clearing brushwood and smaller trees for different purposes in the most simple and most economically advantageous way.
According to the invention, the device has at least one fork-like jaw with means for forcibly holding the material intended to be cleared, while a forcibly controlled cutting blade cuts the material while using the jaw members of the jaw as anvils.
Smaller brushwood as well as trees up to a size of 0 240 mm can easily and very efficiently be cut and handled/graded for further processing, for example chipping with a wood chipper. Since the cutting occurs by means of cutting under high cutting pressure and the actual cutting edge is made of a high- strength steel alloy called HARDOX 450, which has been cold worked by milling in the final machining thereof, a cutting tool which can be used much longer without any deterioration of the cutting capacity thereof is obtained.
The cutter device becomes a very versatile tool in terms of its mobility in that it is mounted to a previously known rotatable and tiltable grapple attachment, which enables it to reach the most inaccessible vegetation. Tilting can take
place about two axes and rotation about one axis. Furthermore, the cutter device is so strongly dimensioned that it can readily be used as a tool in a manner similar to an excavator bucket without running the risk of being destroyed, and can contribute to solving otherwise complex situations, for example if the carrying machine gets stuck or larger rocks or uprooted trees get in the way.
Brief description of the drawings In the following, the invention will be described more closely with reference to an example of an embodiment shown in the attached drawings. The different aspects of the invention, and especially the features and advantages thereof, will easily be understood on the basis of the description and drawings, in which:
Fig. 1 shows a perspective view of a cutter device mounted to a rotating and tilting intermediate member combined with a grapple unit;
Fig. 2 shows a perspective view of the cutting attachment alone, with its means of attachment of standard type for the combination as above;
Fig. 3 shows, in a view from above, the attachment having a cutting part disposed in the upper portion of the figure, and a digging part disposed in the lower portion;
Fig. 4 shows a view corresponding to Fig. 4, in which a cutting blade and a hydraulic cylinder, and the interconnection thereof, are shown as hidden contours. Detailed description of preferred embodiment
Throughout this entire description, terms like upper, lower, above and below are intended to have their usual meaning when the attachment is in a
position corresponding to the one prevailing when the unit has been connected to the swing and tilt assembly having grapple arms.
From Fig. 1 , it can be seen how a complete cutter device 1 is demountable by means of a hydraulic quick coupling (not shown), but is fixedly connected to the bottom side of a grapple module 2. The grapple module 2, in its turn, is fixedly attached to the bottom side of a rotatable and tiltable attachment 15 by means of screw connections, to allow a maximum rotation of +/- 180° about an axis definable in the mounted position through both the grapple module 2 and the unit 1 , and, in the corresponding position, tilting of the grapple module 2 about an axis which is parallel to the gripping direction of the grapple module 2. By means of a rotary device (not shown, but conventional and well-known e.g. for excavating purposes), disposed on the working arm of the supporting machine, the entire grapple module 2 is rotatable about an axis which is transverse to the working arm. Thereby, the cutter attachment 1 thus becomes pivotable about one axis and rotatable about two axes. The ability to rotate about an axis A is controlled by means of two single acting hydraulic cylinders 3, whereas the ability to rotate about an axis B is controlled with the usual hydraulic cylinder (not shown) of the working arm. The grapple module 2 comprises two hydraulically operated grapple arms 4a and 4b, respectively. A standard type quick attachment device 5 with two pivot pins is disposed at the upper part of the grapple module 2 for attachment thereof to the working machine. This attachment device makes it possible to rotate the grapple module about the axis A with standard components disposed on the working machine.
Henceforth, the cutter device 2 can be seen alone in Fig. 2. The unit 2 has a quick attachment device 8, which is intended to be grasped and held firmly by hydraulically operated pivot brackets (not shown), which are standard on the grapple module 2. Furthermore, in this figure, also something which can be described as a gripper jaw 6, provided with anvils and a strongly dimensioned cutting blade 7 of cold-worked high-strength steel
reciprocatingly disposed in this jaw, can be seen. The cutting blade is operated in a reciprocating manner under the influence of a double acting hydraulic cylinder 8, which is not shown in this figure, but is disposed within the unit 2 (see Fig. 4).
Fig. 3 shows the cutter device 1 , in a view from above, in such a way that the curvature of the gripper jaw 6 is clearly evident. The curvature thereof at the left-hand side of the jaw 6, as seen in the figure, has a smaller radius than its right-hand counterpart. Furthermore, from this figure, as well as from the two figures 1 and 2, it is evident that the jaw members are provided with strong friction-increasing teeth 13 on their twig or branch receiving sides, which teeth serve to prevent slipping between the material intended to be cut and the jaw members 6 and the cutting blade 7, respectively. The unit 1 has two digging teeth 14 disposed at the rearward lower part thereof, the purpose of which teeth is to make the unit suitable for smaller earth-moving operations, which otherwise would require the use of a conventional excavator.
Finally, Fig. 4 shows a view of the unit 1 which, in combination with hidden contours of the parts disposed inside the unit 1 , gives an overall picture of how the unit 1 is configured inside. The hydraulic cylinder 8 is pivotally attached 9 to the inside of the unit 1 , whereas at its other end it is pivotally attached to an operating arm 10 disposed on the cutting blade 7. The cutting blade, in its turn, is pivotally attached, at 11 , to the housing of the unit 1 , so that the cylinder 8 will be able to eccentrically actuate the cutting blade to be eccentrically pivoted along an arcuate path, which is defined by the numeral 12.
The function of the unit which is the subject of the present publication is as follows. After having attached the swing and tilt unit with associated grapple module to the working arm of an excavator or a backhoe, the cutter device can easily be attached. The cutter device and the grapple module are connected to the hydraulic system of the excavator or tractor by connecting
hydraulic quick couplers, and can be operated by means of the operating units supplied as a standard with such a machine. The grapple module 2 with associated cutter device 1 is operated into close proximity to the material which is to be cut substantially irrespective of growth direction, whereupon the grapple arms are actuated to clamp the material therebetween. If the device is viewed from above, the initial position of the cutting blade 7 is that it is accommodated in the right-hand gripper jaw member 6 when viewed in this manner. With the vegetation held in close contact with the teeth of the gripper jaw, the cutting blade is operated to perform a cutting action by means of the hydraulic cylinder, wherein the outermost end of the cutting blade 7 moves along the arcuate path 12. When the cutting blade has reached the left-hand side of the gripper jaw, most of the cutting has already been done, but if any tough fibres remain, these are cut in cooperation with a steel anvil, which overlaps with the cutting blade during the movement thereof. Thereupon, the cutting blade returns to the initial position, and is also capable of performing some less demanding cutting operations during this return movement, since the cutting blade is also sharp on the trailing edge thereof. Thereby, the grapple module can hold the cut material and it can be moved/graded in a chosen manner by means of the working arm of the machine.
It should be noted that the reader of this document, by studying the drawings and the description of the invention attached to the present publication, should be able to appreciate that variations of the shown embodiment of the invention are encompassed within the scope of the invention as it is defined in the claims.