Abstract:
A digging attachment for a skid steer loader which comprises a bucket, a shaft mounted cutter reel and a drive means. The drive means is operatively connected to the bucket and the powered cutter reel. The powered cutter reel includes a plurality of digging members which may be rotated about the shaft of the cutter reel when the drive means is activated so as to dig into soil and draw the soil into the bucket.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]    This application claims priority from U.S. provisional application No. 60/175,629, filed Jan. 12, 2000, the entire contents of which are incorporated herein by reference. 
     
    
     
       STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH  
         [0002]    Not Applicable  
         BACKGROUND OF THE INVENTION  
         [0003]    1. Field of the Invention  
           [0004]    This invention relates to a hydraulically operated attachment for a front-end loader. The invention is designed specifically for attachment to smaller construction vehicles such as skid steer loaders. The present invention is directed to a concept for a new soil excavation implement and bucket attached to the skid steers and similar size tractors that will enable the skid steers to be used to excavate in virgin soils or similarly compacted earth while avoiding the problems described above. The overall function of this inventive excavation implement and bucket is to perform small earth moving work which is comprised of cutting, transporting, dumping and grading materials. It is not intended for loading trucks.  
           [0005]    2. Description of the Related Art  
           [0006]    Skid steer loaders are relatively small hydraulic wheel loaders with a lifting boom that can be easily fitted with a variety of attachments by means of a lock-on mechanism commonly known as a quick-tach. In addition to the lifting action of the boom there is a dumping pivot action on the boom end. When equipped with a bucket the skid steer loader may be used for digging, pulverizing material, transporting material, and grading.  
           [0007]    In addition to a variety of types of buckets, there are many other attachments which may be affixed to the lifting boom such as trenchers, augers, brooms, rototillers, vibratory rollers, cold planers, jack hammers, back hoes, etc. Attachments such as rototillers and augers, are powered by hydraulic motors in addition to the boom lift and dump actions These motors are generally driven by oil pumped from the skid steer loader hydraulic system through quick disconnect hose connections.  
           [0008]    There has been rapid development of accessory power attachments for a skid steer machine. The skid steer machines as known generally have a surplus of hydraulic power for use with any desired type of accessory. As equipped with digging buckets, and operating like a conventional wheel loader, skid steers consume only a small fraction of their available horsepower. The majority of the total horsepower is available for the powered attachments. So as with basic tractors, skid steers are power dense, relative to their size.  
           [0009]    Therefore, skid steers are basically a multi-function powered unit, capable of performing a wide variety of tasks. However, the performance of the skid loader is typically reduced during work such as in the digging of established soil. In these instances the skid loaders have more than enough horsepower for this task, however, they simply don&#39;t have sufficient traction to excavate established soil. A skid loader used for digging established soil may experience difficulties such as the spinning of tires which dig pockets and pile up mounds. As the loader runs over these obstructions, it is bounced and pitched which further hampers traction as well as interfering with the ability to control the cutting process of the bucket. There are many small scale excavating jobs which allow access to nothing larger than a skid steer, yet the digging capability of the skid steer is not sufficient for the task. Often, in these cases, back hoes are used for the digging and the skid steer loader is used to transport and grade the excavated-material.  
         BRIEF SUMMARY OF THE INVENTION  
         [0010]    This invention provides for a unique skid steer bucket which is equipped with a powered cutter reel, set crosswise, and positioned ahead of the bucket floor cutting edge. The reel cutter may have many rectangular knives which strike the ground flatwise, like paddles. The reel turns in a climb cutting rotation to the ground. In other words, the top of the reel moves forward so that the bottom is cutting soil and throwing the soil back into the bucket from the bottom side of the reel. There may be some cases where it would be preferable to reverse the reel rotation so that it throws the soil over the top, and consequently, higher into the bucket.  
           [0011]    The cutting reel may be mounted in a pair of shock resistant sealed bearings positioned on each side of the bucket. At one end of the reel shaft is located a roller chain sprocket with a roller chain or other connection means running to the rear of the bucket just outside of the bucket end wall. At the rear of the bucket, the chain connects to a drive sprocket of a hydraulic motor.  
           [0012]    In at least one embodiment of the invention the hydraulic motor is enclosed in a protective housing positioned within the confines of the bucket. The hydraulic motor may be powered from the tractor auxiliary or high flow hydraulic system through the use of quick disconnect hose couplings. The operator control for the reel drive motor allows the cutter reel to be engaged forwardly, stopped, or reversed. If necessary, a speed control may be added to the motor.  
           [0013]    The basic bucket floor cutting edge follows directly behind the cutting reel, at approximately the same elevation as the cut path of the cutting reel. However the bucket cutting edge does not cut virgin earth, it merely serves as an apron to receive the earth that is kicked off of the reel. The actual floor of the cut pass may be made exclusively by the knives of the spinning cutter reel. The cutting reel generally does not cut the end zones located outside of the bucket which are occupied by the bearings and especially the chain and sprocket. So the structure that supports and protects the bearings and sprocket must plow through the ground without the aid of the cutting reel.  
           [0014]    A piercing point is positioned forwardly to each of the bearing support structures where the piercing points function as plows to reduce the force required to penetrate the undisturbed soil. These points may have a wide variety of characteristics. In at least one embodiment of the invention the points may be chisel shaped, set flat to the ground, and may be a few inches wide so that they cut and lift the soil just ahead of the bearing support structures. The chisels cut the form of the comers where the cut pass sides meet the cut pass floor. In addition to the bottom cutting chisels, the piercing points may be fitted with side cutting knives. Together, the side knife and bottom chisel of each piercing point shears each corner of the cut pass, forcing the material upward and inward, making it accessible to the cutter reel.  
           [0015]    The two corner piercing points pierce and lift the undisturbed soil just ahead of the cutter reel end bearings. The reaction to the lifting action tends to suck the bucket deeper into the ground. This downward pull of the bucket is countered by the climbing rotation of the reel cutter which tends to lift the bucket upward. As these two forces work against each other, they combine into a third resultant force direction that tends to pull the bucket forward, adding to the piercing force of the points. In this way, the cutter reel not only breaks the soil encountered as the tractor pushes it forward, but adds to the push of the tractor by pulling itself forward, into the soil.  
           [0016]    Usually the size of a skid steer bucket is limited by the tractor&#39;s ability to force it to cut, and the potential instability of lifting a loaded bucket for placement of aggregate within a truck. The use of the cutter reel on a bucket provides for a cutting force from an independent powered cutter as opposed to forward penetration of a bucket cutting edge, and because a bucket equipped with a cutter reel is not intended to be lifted high for loading trucks, its capacity can be relatively higher, thus maximizing its transport function. Therefore, this new bucket may have a capacity of one cubic yard or more when used on mid to large size skid steer loaders.  
           [0017]    Compared to typical skid steer buckets, this new bucket cutter reel combination permits use of a taller and shorter bucket from front to back. The cutter reel preferably throws soil high enough to fill a taller bucket. The throwing of soil preferably places the center of mass of the load as close as possible to the tractor to reduce forward tipping forces which may result from the cantilevered load weight on the tractor.  
           [0018]    In operation, this bucket cutter reel combination is advanced into the cut with the cutter reel under full power. The cuter reel throws the soil up, into the bucket, pulverizing it in the process. If the cutter reel encounters a rock that is too large to pass between the cutter reel center shaft and the bucket cutting edge, the cutter reel will simply stall actuating an operation circuit into bypass. An operator may then toggle the cuter reel to reverse, thereby unjamming the clog. If the obstruction is too large, the operator must work around it.  
           [0019]    Once the bucket is full, it may be elevated a sufficient distance to clear the ground, whereupon the cutter reel may be disengaged. The bucket may be moved to the dumping location and tipped to the dump position to disperse transported material. Material may either be dumped in one pile or dumped while moving in order to spread it over a desired area. During the dump cycle, the soil maybe further pulverized by running the cutter reel, allowing the soil to pass through the cutter reel as it falls out of the bucket. This second pass of material through the rotating cutter facilitates production of a uniform rate of dumping which aids the grading and finishing process.  
           [0020]    As previously explained, the purpose of the cutter reel is to reduce the tractive effort needed to fill the bucket, however, a second benefit is the inevitable soil pulverization. Soil pulverization facilitates a bucket being filled without voids for efficient transportation, and the pulverized soil is easier to spread and grade. During the grading process, the bucket may be set in the cutting position (with the bucket floor flat to the ground), with the cutter running in reverse. The cutter may then kick the soil ahead for further pulverization while having the effect of dozing the soil forward as a means of transport and/or spreading. This technique may be used for light cutting in virgin earth whereby the soil is cut and kicked forward by the cutting reel, forming a heap which is being constantly reground as it is pushed forward. This process is called dynamic dozing. 
       
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS  
       [0021]    A detailed description of the invention is hereafter described with specific reference being made to the drawings in which:  
         [0022]    [0022]FIG. 1 is a perspective view of an embodiment of the invention;  
         [0023]    [0023]FIG. 2 is a close-up partially cut-away perspective view of the embodiment shown in FIG. 1;  
         [0024]    [0024]FIG. 3 is a reverse partially cut-away perspective view of the embodiment shown in FIG. 2;  
         [0025]    [0025]FIG. 4 is a top down view of an embodiment of the invention;  
         [0026]    [0026]FIG. 5 is a side view of an embodiment of the invention depicted in its operational environment; and  
         [0027]    [0027]FIG. 6 is an alternative perspective view of an embodiment of the invention.  
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0028]    The present invention, as may be seen in FIG. 1 is referred to as a self loading bucket or dog bucket and is indicated generally at  10 . Dog bucket  10  further comprises a bucket  12  of a skid loader such as a Bobcat® or a tractor.  
         [0029]    The bucket  12  includes a frame  14  comprising a floor  16 , a back wall  18 , and a pair of side walls  20  and  22 . The bucket  12  may be composed of a variety of materials but is typically steel or an alloy thereof. The side walls  20  and  22  include shock resistant sealed bearing supports  24  for rotatably mounting the shaft  26  of a cutter real  28 . Alternatively, the side walls  20 ,  22 , may each include an aperture adapted to receive the shaft  26  where the shock resistant sealed bearing supports  24  are positioned adjacent to and exterior of the side walls  20 ,  22 . In another alternative embodiment, one set of shock resistant bearing supports  24  may be positioned forwardly of the leading edge of each of the respective side walls  20 ,  22 . Side wall  20  includes a drive mechanism  70  which includes a roller chain sprocket  30  provided at one end of the cutter reel  28 , a drive sprocket  32 , and one or more support sprockets  72 . The drive mechanism  70  may be integral with and/or releasably secured to the exterior of the side wall  20 . In the embodiment shown the drive mechanism  70  is chain driven by drive chain  54 . Alternatively, the drive chain  54  may be replaced with a belt drive and/or other drive mechanism to impart rotation to the cutter reel  28  during use of the self-loading bucket  10 . The drive sprocket  32  is in mechanical communication with a hydraulic motor  34  (shown in FIG. 2) and is generally positioned at the back and to the interior of the bucket  12 . Alternatively, the hydraulic motor  34  may be positioned to the rear of the bucket  12  and affixed to the exterior of the back wall  14 . In this embodiment, the drive sprocket  32  is preferably positioned proximate to the side wall  20  and rearwardly to the back wall  18 . The hydraulic motor  34  is preferably powered by the tractor auxiliary hydraulic flow system (not shown). The bucket floor  16  extends to the front  36  of bucket  12  to form a cutting edge  38 . The cutting edge  38  may serve as an apron to receive soil thrown into the bucket  12  from the cutter real  28 .  
         [0030]    The powered cutter reel  28  is positioned forwardly to the cutting edge  38  of the bucket floor  16 . The cutter reel  28  has a shaft  26  and a plurality of digging members  40  which function like paddles for removal of soil. The digging members  40  may include a variety of shapes and sizes as well as arrangements. In the embodiment shown the digging members  40  may be characterized as a plurality of rectangular knives. The cutter reel  28  may be rotated in a clockwise manner such that the paddles  40  cut downward into the soil and throw soil backwards into the bucket  12 . The direction of the cutter real  28  may be reversed for the purpose of dislodging blockages or dispersing soil from within the bucket  12  onto the ground or for other purposes as may be desired.  
         [0031]    The cutter real  28  and the components thereof are typically constructed from metal such as steel or an alloy thereof, however, other materials may also be utilized such as, titanium, iron, etc.  
         [0032]    The cutter real  28  is adapted for operation via a drive such as the hydraulic motor  34 , as may best be seen in FIG. 2. The hydraulic motor  34  is preferably in fluid communication with the auxiliary hydraulic system of the skid loader (not shown) by way of hydraulic feed lines  42  which may be equipped with quick connect/disconnect ends  44 , such as may be seen in FIG. 3.  
         [0033]    As may be seen in FIG. 2 the hydraulic motor  34  may be positioned within the bucket  12 . However, in order to protect the motor  34  from dirt and debris which would other wise fill the bucket  12  during use, the hydraulic motor  34  is preferably contained in a protective housing or motor house  46 , such as may be seen in FIG. 1.  
         [0034]    In the embodiment shown in FIGS. 1 and 2, the motor house  46  is located in a back corner of the bucket  12 , against the floor  16 , the back wall  18  and side wall  20 , as such, the motor house  46  may be a three sided structure which completely covers the motor  34  and may be welded and/or bolted to the adjacent bucket surfaces  16 ,  18  and  20 . Alternatively, one or more cleats  48 , such as may be seen in FIG. 2, may be pre-welded into the bucket  12 . The housing  46  may then also be bolted and/or welded to the cleat  48  as shown.  
         [0035]    As indicated above, the hydraulic motor  34  may be hydraulically powered by hydraulic feed lines  42  which lead from the hydraulic motor  34  to the hydraulic fluid pumping system of the skid steer loader. As may be seen in FIG. 3, the hydraulic lines  42  extend from the hydraulic motor through an opening  50  in the back wall  18  of the bucket  12 . The hydraulic lines  42  may extend several feet from the motor. In order to protect the hydraulic lines  42  from potential damage the lines  42  may be enclosed in-part by a hose duct or guard  52 . The hose duct  52  encloses the lines  42  as they pass out of the opening  50  and extend along the back wall  18  of the bucket  12 . The hose duct  52  may be constructed from any type of suitable protective material, including but not limited to, steel, particularly light gauge steel. The hose duct  52  may be bolted and/or welded to the bucket  12 .  
         [0036]    The hydraulic motor  34 , shown in FIG. 2, is engaged to the drive sprocket  32  which is depicted in FIGS. 1 and 3. The hydraulic motor  34 , may be engaged to the drive sprocket  32  by a shaft  80  which preferably passes through the side wall  20  proximate to the hydraulic motor  34 . Alternatively, the hydraulic motor  34  may be positioned rearwardly to the back wall  18 . If the hydraulic motor  34  is positioned rearwardly to the back wall  18  then the drive sprocket  32  is also required to be positioned rearwardly to the back wall  18 . In the embodiment shown, the drive sprocket  32  is operatively engaged to the roller chain sprocket  30  by a drive chain  54 . While the embodiment of the cutter real  28  is chain driven via a hydraulic motor  34 , in alternative embodiments the cutter real  28  may be directly hydraulically driven, belt driven, or shaft driven as may be desired.  
         [0037]    Turning back to FIG. 1, it may be seen that each of the side walls  20  and  22  may also include a piercing point  56 . Each piercing point  56  may be integral to the bucket frame  14  or may be welded and/or bolted thereon. The piercing points  56  extend horizontally from the front  36  of the bucket  12 . The piercing points  56  may include a chisel shaped edge  58  which is designed to cut and lift the soil ahead of bearing supports  24 . In addition, side cutting knives/plows  60 , as may best be seen in FIG. 4, also force soil upwardly and inwardly away from the bearing supports  24 . Alternatively, a standard bucket  12  may be utilized for retrofitting to include the frame  14  and cutter reel  28 . In this embodiment, the frame  14  includes forwardly located piercing points  56  where one piercing point  56  is preferably positioned to each side wall  20 ,  22  forwardly of, and proximate to, the cutting edge  38 .  
         [0038]    In FIG. 4, a cover or bonnet  62  may be seen mounted to the frame  14 . The bonnet may be welded and/or bolted, or otherwise fastened to the bucket frame  14 . The bonnet  62  is a light weight enclosure that is placed on the bucket  12  to provide greater soil containment ability. Because the bonnet  62  is not subjected to active soil digging or pushing pressures, the bonnet may be made of a variety of materials such as steel, but may also be made of lighter weight materials such as aluminum or even plastic. In general, as may be seen in FIGS. 4 and 5, the bonnet  62  includes a pair of upwardly and inwardly extending angled sides  82  and upwardly and forwardly extending back wall  64  and a horizontally extending roof  84  as engaged to the back wall  64  and angled sides  82 . In general, the bonnet  62  may be in the shape of a standard non-modified production bucket for a skid or front end loader. It should be noted that other shapes may be utilized for the bonnet  62  at the discretion of an individual. In general, the bonnet  62  may be secured to the top of the frame  14  and back wall  18  through the use of bolts and nuts and/or welding. Alternatively, any desired type of permanent and/or releasable mechanical fastener may be utilized to secure the bonnet  62  to the frame  14  and the back wall  18  at the discretion of an individual. The back wall  64  of the bonnet  62  may include a window or grate  66  to allow the tractor or skid loader operator the ability to see into the bucket  12  and visually monitor the load and the cutting action of the cutter real  28 . Alternatively, where the bonnet  62  is constructed of plastic, the plastic may be clear to provide a clear line of sight from the operator into the bucket  12 .  
         [0039]    In an alternative embodiment of the invention, the bonnet  62  my extend forward to act as a guard for the cutter real  28 . Alternatively, a separate guard assembly may be attached to the frame  14  to partially cover the cutter real  28  thereby preventing accidental contact with the cutter blades  40  from above.  
         [0040]    Turning to FIG. 5, the dog bucket  10  is depicted in operation. During operation, the action of the dog bucket  10  causes the bucket  12  to be sucked into the ground. This action is countered by the climbing forces resulting from the rotation of the reel  28  which in combination pull the bucket  12  forwardly through the soil  68 . The piercing points  56  and side cutting knives/plows  60  also move soil  68  inwardly along the drive mechanism  70  and bearings  24  into the interior of the bucket  12 . The rotating action of the cutter reel  28  and knives/paddles  40  function to break apart established soil for movement into the bucket  12 . The bucket floor  16  cutting edge  38  is therefore provided with the ability to have an enhanced depth for removal of soil.  
         [0041]    In an alternative embodiment as may be depicted in FIG. 6, the frame  14  may be mechanically secured to a standard bucket  12  of a skid or front end loader. The frame  14  in this embodiment is generally formed of a first cutter reel support  90  and a second cutter reel support  92 . The first and second cutter reel supports  90 ,  92  may be respectively secured to the side walls  20 ,  22  by the use of bolts and/or welding or any other secure mechanical fasteners. The first cutter reel support  90  preferably includes the features of the roller chain sprocket  30 , drive sprockets  32 , drive mechanisms  70 , and support sprockets  72  as earlier described.  
         [0042]    The first and second cutter reel supports  90 ,  92  preferably each include the bearing supports  24  for support of the shaft  26  and cutter reel  28  as earlier described. In addition, each of the first and second cutter reel supports  90 ,  92  each preferably include a piercing point  56 , chisel shaped edge  58 , and knife plows  60  as earlier described.  
         [0043]    In this embodiment, a standard skid or front end loader bucket  12  is modified or retrofitted to include the first and second cutter reel supports  90 ,  92  and cutter reel  28 .  
         [0044]    The first side wall  20  is therefore required to receive at least one aperture to accommodate the shaft  80  of the hydraulic motor  34  as engaged to the drive sprocket  32 . A second aperture may also be required for receipt of the bearing supports  24  and shaft  26  as connected to the roller chain sprocket  30  and cutter reel  28 . Alternatively, the first cutter reel support  90  may be secured to the side wall  20  by welding and/or bolts and nuts where the first cutter reel support  90  includes the bearing supports  24  positioned within an aperture for support of the shaft  26  as connected to the roller chain sprocket  30  and cutter reel  28  which are preferably positioned forwardly of the leading edge of the side walls  20 ,  22 . It should be noted that the second cutter reel support  92  is preferably attached in an identical location relative to the side wall  22 . The side wall  22  may therefore be required to include an aperture to receive bearing supports  24  and shaft  26  of the cutter reel  28 .  
         [0045]    The hydraulic motor  34  in this embodiment is preferably positioned interior to the bucket  12  proximate to the side wall  20  and back wall  18  as earlier described.  
         [0046]    The other features as identified herein may also be preferably included for retrofit of a standard skid or front end loader bucket  12  to accommodate the attachment of the cutter reel  28  excavation accessory as illustrated and disclosed herein.  
         [0047]    In addition to being directed to the embodiments described above and claimed below, the present invention is further directed to embodiments having different combinations of the features described above and claimed below. As such, the invention is also directed to other embodiments having any other possible combination of the dependent features claimed below.  
         [0048]    The above examples and disclosure are intended to be illustrative and not exhaustive. These examples and description will suggest many variations and alternatives to one of ordinary skill in this art. All these alternatives and variations are intended to be included within the scope of the attached claims. Those familiar with the art may recognize other equivalents to the specific embodiments described herein which equivalents are also intended to be encompassed by the claims attached hereto.