Patent Publication Number: US-2002005097-A1

Title: Apparatus and method for cutting twine wound about a bale

Description:
BACKGROUND OF THE INVENTION  
       [0001] 1. Field of the Invention  
       [0002] This invention relates in general to farming equipment and tractors. More particularly, this invention relates to an apparatus and method for severing twine from a bale.  
       [0003] 2. Background  
       [0004] In modern farming, bales of hay or other straw-like material or herbage are used for feeding animals or for other general purposes on the farm. The bales often weigh in excess of 1,000 pounds, and are typically arranged in a spiral and wrapped with twine about the periphery of bale so that the bale can be transported using a tractor having a loader. Conventional tractor loaders have a bucket and a grapple, where the grapple has tines or forks for spearing the bale.  
       [0005] As the bale is moved from place to place using the loader of the tractor, the bale is placed in a location on the farm where it will be unraveled and distributed for use or consumption. Conventionally, a farmer or other user manually cuts or manually severs the twine about the bale so that the bale can be distributed or consumed. This manual cutting operation generally requires that the farmer or user leaves the seat of the tractor in order to cut the twine, which can be inconvenient to the farmer.  
       [0006] Tractors are often equipped with protective cabins in which the farmer or user sits protected from the bad weather conditions, such as cold, rain, or excessive heat. In such situations, cutting or severing the twine from about the bale can be even more inconvenient.  
       [0007] It is with these shortcomings of the existing art in mind that the present invention was developed. What is needed is a method and apparatus for cutting the twine about a bale so that the cutting operation can be controlled and performed from the operator&#39;s seat within the tractor.  
       SUMMARY OF THE INVENTION  
       [0008] In light of the above, therefore, according to a broad aspect of the invention, an apparatus for severing twine from a bale supported by one or more grapple arms of a tractor is disclosed. The apparatus comprises a slide bar mounted to at least one grapple arm, the slide bar having a first end and a second end, a blade riding on the slide bar, the blade oriented on the slide bar so that the blade contacts portion of the twine as the blade moves along the slide bar, and a motor coupled to the blade for controllably moving the blade along the slide bar. The motor can be a reversible dc motor controllable by a switch, or a hydraulic motor.  
       [0009] The slide bar can have a generally U-shaped cross-section with a top portion and a bottom portion, with a channel formed along the top portion. The assembly can further include a slide block connected to the blade, the slide block adapted to slide within the channel along the slide bar while supporting the blade. A visual indicator indicating the position of the blade relative to the slide bar can be used in conjunction with the blade and slide block.  
       [0010] In one example, the assembly can include a first and second sprocket, the first sprocket coupled to the slide bar about the first end, and the second sprocket coupled to the slide bar about the second end, the first sprocket coupled to the motor for rotating the first sprocket about a fixed axis, and a chain connecting the first sprocket to the second sprocket, the blade coupled to the chain for movement of the blade along the slide bar. The slide bar can have a slot for receiving a bolt, and the second sprocket is mounted to the slide bar through the bolt, and the sprocket rotates about the bolt. A substantially U-shaped tensioning bracket can be mounted about the second end of the slide bar, the bracket having first and second opposing legs coupled to a base portion, each leg having axially aligned opening for receiving the bolt, the base having an opening for receiving a tensioning bolt for adjusting the tension of the chain about the sprockets.  
       [0011] In this manner and using this twine cutting assembly, the bale can be cut while supported by the loader and while the farmer is inside the driver&#39;s compartment of the tractor.  
       [0012] Also disclosed herein is a tractor having a driver&#39;s compartment having a set of controls for controlling the operation of the tractor, a loader having at least a pair of grapple arms coupled to grapple tines for piercing a bale having twine thereabout, and a twine cutting assembly. The twine cutting assembly includes a slide bar mounted to at least one grapple arm, the slide bar having a first end and a second end, a blade riding on the slide bar, the blade oriented on the slide bar so that the blade contacts portion of the twine as the blade moves along the slide bar, and a motor coupled to the blade for controllably moving the blade along the slide bar. A control is located within the driver&#39;s compartment for controlling the operation of the motor.  
       [0013] In accordance with the present invention, the twine cutting assembly can be mounted to either the grapple arms, the tines, or the bucket of the tractor.  
       [0014] A method of cutting a portion of twine wrapped about a bale is also disclosed herein, the method comprising the steps of positioning a grapple of a tractor about a portion of the bale, providing a twine cutting assembly on the grapple, the twine cutting assembly having a blade linearly movable in a direction generally transverse to the direction in which the twine is wrapped about the bale, and in response to a control signal, controllably moving the blade across the twine to cut the twine. The method also includes the step of providing a control within the tractor for generating the control signal.  
       [0015] The foregoing and other features, utilities and advantages of the invention will be apparent from the following more particular description of a preferred embodiment of the invention as illustrated in the accompanying drawings. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0016]FIG. 1 illustrates a tractor having a grapple and a bucket of a loader supporting a feed bale with twine secured thereabout, with an embodiment of the present invention positioned about the grapple arms.  
     [0017]FIG. 2 illustrates an embodiment of the twine cutting assembly of the present invention mounted to a pair of grapple arms which are coupled to a bucket.  
     [0018]FIG. 3 illustrates a plan view of one embodiment of the twine cutting assembly of the present invention, showing the slide bar and the blade.  
     [0019]FIG. 4 illustrates a top view of one embodiment of the present invention, wherein the slide bar, the blade, and the motor can be seen.  
     [0020]FIG. 5 is a sectional view taken along section lines  5 - 5  of FIG. 3 showing a sprocket and chain coupled to the blade through a slide block riding along the slide bar, in accordance with one embodiment of the present invention.  
     [0021]FIG. 6 is a sectional view taken along section lines  6 - 6  of FIG. 4 illustrating a cross section of the slide bar, the blade, and the slide block, in accordance of one embodiment of the present invention.  
     [0022]FIG. 7 illustrates a sectional view taken along section lines  7 - 7  of FIG. 4 illustrating the slide bar and sprocket.  
     [0023]FIG. 8 illustrates a tractor having a loader having a bucket and grapple arms with tines in an open position approaching the bale with one embodiment of the present invention mounted to the grapple arms.  
     [0024]FIG. 9 is an illustration of the tractor of FIG. 8 as the bucket of the loader of the tractor contacts the bale.  
     [0025]FIG. 10 illustrates the tractor of FIG. 8- 9  as the bale is secured and lifted by the tractor bucket and grappler tines and the blade and slide bar are positioned along the bale, in accordance of one embodiment of the present invention.  
     [0026]FIG. 11 is a sectional view taken along section lines  11 - 11  of FIG. 10, illustrating the position of the blade and the slide bar of the present invention relative to the grapple arms and the twine about the bale, in accordance of one embodiment of the present invention.  
     [0027]FIG. 12 illustrates the twine and the bale of FIG. 11 after the blade has cut the twine in accordance with one embodiment of the present invention.  
     [0028]FIGS. 13A and 13B illustrate alternate embodiments for the sprocket and chain drive members of the present invention.  
     [0029]FIG. 14 illustrates a circuit block diagram for the electrical connections and controls in accordance with one embodiment of the present invention.  
     [0030]FIG. 15 illustrates two limit switches positioned on the slide bar in accordance with one embodiment of the present invention.  
     [0031]FIG. 16 illustrates a circuit block diagram for the electrical connections and controls in accordance with one embodiment of the present invention.  
     [0032]FIG. 17 illustrates a blade cover positioned over a blade and rotatable about a point for covering the blade when the blade is not in use, in accordance with one embodiment of the present invention.  
     [0033]FIG. 18 illustrate a blade cover positioned over a blade for covering a portion of the blade, in accordance with one embodiment of the present invention.  
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
     [0034] A twine cutting assembly suitable for use on tractor or other farming implement is disclosed herein. The twine cutting assembly includes a slide bar, a blade, and a drive device such as a motor. The blade is coupled to the motor for controllably moving the blade as guided by the slide bar so that the blade passes through and cuts the twine. As will be described in greater detail below, the twine cutting assembly of the present invention can be positioned on various locations of the tractor and can be provided with controls located with the tractor controls so that a farmer or user can cut the twine of a bale from without having to leave the seat of the tractor.  
     [0035] Referring now to FIG. 1, a tractor  30  having a loader  32  is shown where the loader includes a bucket  34  and a grapple  36 , where the grapple has grapple arms  38 , a grapple tines support tube  40 , and a plurality of tines  42  for securing a bale  44  with twine  46  wrapped thereabout. As shown in FIGS. 1 and 2, the twine cutting assembly  50  of one embodiment of the present invention is positioned along the grapple in one example. It is understood that the precise position and placement of the twine cutting assembly is a matter of choice which depends on the particular structures and geometries of the tractor attachments, such as the bucket  34  or grapple  36 . For instance, the twine cutting assembly could be mounted along various positions of the grapple  36 , grapple arms  38 , grapple tines  42 , or within the bucket  34  at various locations.  
     [0036] Referring to FIG. 2, the twine cutting assembly  50  is shown coupled to a pair of the grapple arms  38  between the bucket  34  of the loader and the tines  42  of the grapple arms. A pair of mounting brackets  60  are shown wherein the mounting brackets are generally each rectangular in shape and have a twist  62  along their length so that one end  64  of the mounting bracket can be coupled to a vertical surface  66  of the grapple arm  38  in a vertical orientation, while the other end  68  of the mounting bracket can be coupled to and support the twine cutting assembly along a horizontal surface  70  in a horizontal orientation. The shape, number, and position of the brackets can be varied depending on the particular geometries of the surfaces to which the twine cutting assembly  50  is attached.  
     [0037] Referring to FIG. 2 and as discussed above, the twine cutting assembly includes a slide bar  80 , a blade  82 , and a drive device  84  such as a motor. The blade  82  is mechanically coupled to the motor for controllably moving the blade as guided by the slide bar  80  so that the blade passes through and cuts the twine.  
     [0038] The slide bar  80  has a generally elongated and rectangular shape, and in one example is mounted to the grapple arms  38  such that the blade  82  is oriented to contact the twine as the blade  82  moves along the slide bar  80  to cut the twine on the bale. Referring to FIGS. 2, 3,  4 ,  5 ,  6 ,  7 , the slide bar  80  is generally U-shaped in cross-section with a top portion  86  and bottom portion  88 , and a channel  90  formed along the top portion therein, in one embodiment of the invention. In one example, the slide bar  80  is approximately seven feet long and three inches in width, with the channel  90  being approximately one inch in width, with the height of the slide bar being approximately four inches. These dimensions are by way of example only, as the slide bar  80  can be sized and shaped according to the dimensions of the particular application.  
     [0039] Referring to FIG. 5, the blade or sickle  82  is shown having a first edge  92  and a second edge  94  for cutting the twine. The two edges  92 ,  94  are provided so that the twine can be cut while the blade is traveling in either direction along the slide bar  80 . The blade  82  is provided with a pair of openings  96  for securement to the slide block  98 , described below. It is understood that while the blade  82  shown is a two-edged, V-shaped blade, other blade designs could be utilized which would provide the same benefits. For instance, a blade with a single edge could be used. Additionally, a blade cover can be provided for covering the blade while the blade is not in use. Examples of blade covers are shown in FIGS. 17 and 18, and will be described below.  
     [0040] The motor  84  shown in FIGS. 4 and 6 is preferably a DC motor capable of operating with conventional 12-14 volt DC supply voltage, as provided by the battery on a tractor. As seen in FIGS.  5 - 6 , the motor has a shaft  100  which is mechanically coupled to the blade  82  for moving the blade along the slide bar  80 .  
     [0041] Preferably, the motor  84  is rated for low speed, high torque operation in order to generate sufficient force to drive the blade  82  through the bale and cut the twine, as the twine can be under high tension due to the weight of the bale. Further, the motor  84  is preferably reversible in direction. A 12-volt DC motor, winch model 6×190-9, available from Grainger, Inc. of Fargo, N. Dak., has been found to be suitable. A hydraulic motor or “orbit” motor could also be used, where a low speed, high torque motor usable on farm equipment would also be desirable. A hydraulic motor is particularly appropriate where the tractor is provided with hydraulic supply lines for accessories, and being controllable from the driver&#39;s compartment of the tractor, such as with modern tractors. Examples of such motors include the Char-Lynn H, S, and 2000 series hydraulic motors available from Bailey Sales Corporation of Knoxville, Tenn. For retrofitting an older tractor, the 12 volt system operates with tractors having electric power available throughout the tractor. Additionally, it is understood that the present invention could operate with tractors having different battery supply voltages.  
     [0042] Preferably, the blade  82  moves at a rate of approximately six (6) inches per second across the slide bar  80 . In this manner, the blade is not moving at an excessively fast rate which may be more dangerous. However, it is understood that the rate at which the blade travels is a matter of choice dependant on the particular implementation.  
     [0043] As seen in FIGS. 6 and 5, the slide block  98  is adapted to slide or move within the channel  90  along the slide bar  80 , where the slide block  98  is coupled to the blade  82  through the pair of openings  96 . The slide block  98  maintains the blade  82  within the channel  90  of the slide bar, which reduces the chance that the blade will dislodge from the twine cutting assembly if the motor  84  becomes disconnected from the blade. The slide block has a mounting plate  99  for attachment of the slide block to a chain or cable, described below. A flexible flag or other visual indicator  100  can be coupled to the blade or the slide block  98  as shown in FIG. 6 through an aperture  102  (FIG. 5) so to assist the farmer or user to visually determine the position of the blade along the slide bar.  
     [0044] The blade  82  can be coupled to the drive device or motor  84  in a number of ways, so that the motor controllably moves the blade  82  along the slide bar  80 . In one example, referring to FIG. 5, a pair of sprockets  110 ,  112  are rotatably mounted about each end of the slide bar, and a chain or belt  114  is positioned about the sprockets  110 ,  112  and coupled to the slide block  98  using mountain plate  99 . The chain  114  is preferably a 14-foot chain of number  40  type. One sprocket  110  is coupled to the shaft  100  of the motor  84  which controllably rotates the sprocket  110  about its mounting. The opposing sprocket  112  is mounted within the slide bar  80  through a sprocket support bolt  116  being movable within a slot  118  so as to permit tensioning of the chain through the position of the bolt  116  and the sprocket  112 .  
     [0045] A tensioning bracket  120  is provided with a tensioning bolt  122 , as shown in FIGS. 3, 4, and  5 . The tensioning bracket  120  is U-shaped and positions the sprocket support bolt  116  within the slot  118 . As the tensioning bolt  122  is tightened, the tensioning bracket  120  moves away from the end of the slide bar  80  so as to increase the tension of the chain  114  until a desirable tension is obtained. An end cap  124  can also be provided so to protect the components internal to the slide bar  80 , and also provides a bearing surface  125  against which the tensioning bolt  122  contacts.  
     [0046] As shown in FIGS. 2, 3, and  6 , a bracket  126  is used to affix the motor  84  to the slide bar  80  and maintain shaft  100  of the motor in a fixed position relative to the slide bar  80  and the sprocket  110 . Spacer blocks  128  can also be used along the motor&#39;s mounting bracket  126  so that the shaft  100  of the motor is properly positioned.  
     [0047] In an alternate embodiment, a cable-pulley/spool system could be utilized, or a belt-pulley system, in place of the chain and sprocket system discussed above, as shown in FIG. 13A. A first pulley or spool  130  is coupled to the motor  132  while the second pulley or spool  134  is spring loaded and coupled to the first pulley  130  through a cable or belt  136  to provide a tension along the cable. A slide block  138  connects the blade  140  to the cable and maintains the blade within the channel of the slide bar (not shown) in the event the cable should fail. In another embodiment, a motor  140  is positioned on the slide block  142  so that the blade  144 , slide block  142 , and motor  140  move along a track  146 , as shown in FIG. 13B.  
     [0048]FIG. 14 illustrates a circuit block diagram for the electrical connections and controls in accordance with one embodiment of the present invention. The reversible motor  84  is coupled to a switch  150  having controls  152  capable of controlling the power (on/off control) and the direction (forward/backwards) of the motor coupled to the battery  154 . In one embodiment, the switch  150  can be a single switching device with three positions: forward, off, and reverse. A suitable switch, for example, is model 6×192-5 available from Grainger, Inc. of Fargo, N. Dak. The control  152  can be located with the driver&#39;s compartment of the tractor so that the farmer or user can control the operation of the twine cutting assembly from within the driver&#39;s compartment.  
     [0049] As shown in FIG. 15, conventional limit switches  160 ,  162  can be provided on both ends of the slide bar  164  so that the blade  166  will travel between a first  168  and second  170  position along the slide bar  164  and the motor  172  can be automatically reversed if desired by the farmer or user. The limit switches  160 ,  162  should be configured to be responsive to the position of the blade  166  or slide block  174  along the slide bar (i.e., the limit switches should trip or become an open circuit when the blade/slide block reaches the respective limit position). FIG. 16 illustrates a circuit block diagram for the electrical connections and controls, in accordance with one embodiment of the present invention, showing the limit switches  180 ,  182  connected in series with the master on/off control  184  so that power  186  to the motor  188  is cut-off when either limit switch is tripped by the position of the blade. It is understood that various configurations of the switches can be used and are a matter of choice as desired, for instance, the switches can be configured to reverse the direction of the motor when the blade/slide block reaches the limit position.  
     [0050] As mentioned above, various blade covers and designs can be used. FIG. 17 illustrates a blade cover  200  positioned over a blade  202  and rotatable about a point  204  for covering the blade when the blade is not in use, in accordance with one embodiment of the present invention. The cover  200  is affixed to the slide block  206  and has a first curved edge  208  so that as the blade/slide block moves in a first direction, the twine and other contents of the bale move the cover  200  away from the blade  202  and expose the blade so that the blade can cut the twine. When the blade/slide block moves in the opposite direction, the second curved edge  210  contacts the contents of the bale and moves the cover  200  back over the blade  202 . A spring (not shown) can be employed to bias to blade cover  200  in the covering position when no external forces are applied to either edge  208 ,  210  of the cover. It is understood that when using the blade and cover of FIG. 17, the twine cutting assembly would only cut twine in the first direction, and a single edged blade would be suitable.  
     [0051] In another embodiment, FIG. 18 illustrates a blade cover  220  permanently positioned over a single edged blade  222  for covering a portion of the blade. The cover  220  can be affixed to the blade  222  and the slide block  224 , and the cover has a first curved edge  226  which, when in contact with the twine as the blade/slide block move in a first direction, can move the twine towards the blade&#39;s edge  228  for cutting. The second curved edge  230  of the blade cover  220  is curved to reduce the force required to move the blade/slide block in the opposite direction. It is understood that when using the blade  222  and cover  220  of FIG. 18, the twine cutting assembly would only cut twine in the first direction.  
     [0052] Alternatively, a blade cover could be mounted and fixed at one end of the slide bar to cover the blade when the blade is positioned at that end, so that the blade is covered when the twine cutting assembly is not in use. The blade would be returned to the position under the cover after each use.  
     [0053] In accordance with the invention, and as shown in FIGS.  8 - 10 , a farmer or user can position and secure a bale  308  using the tractor&#39;s bucket  302  and grapple  304  and selectively pass the blade  306  through a portion of the bale to cut the twine  308  so that the bale can be distributed, as shown in FIGS.  11 - 12   
     [0054] In this way, the farmer or user can perform these operations without the necessity of leaving the seat of the tractor. FIG. 8 illustrates a tractor  301  having a bucket  302  and grapple arms  303  with tines  305  in an open position approaching the bale  300  with one embodiment of the twine cutting assembly  307  mounted to the grapple arms  303  as shown. FIG. 9 shows of the tractor of FIG. 8 as the bucket of the tractor contacts the bale, while FIG. 10 shows the bale being secured and lifted by the tractor bucket and grappler tines, and the blade and slide bar are positions along the bale, in accordance of one embodiment of the present invention. The blade is then passed through the bale in order to cut the twine, as described above, using the control located within the driver&#39;s compartment of the tractor.  
     [0055] The twine cutting assembly can be included in an “after-market” assembly, either together with a loader, grappler and/or a bucket, or as a separate assembly to retrofit existing tractors. The twine cutting assembly can also be provided and integrated into a production design for a new tractor.  
     [0056] While the invention has been particularly shown and described with reference to a preferred embodiment thereof, it will be understood by those skilled in the art that various other changes in the form and details may be made without departing from the spirit and scope of the invention.