Patent Publication Number: US-8112913-B2

Title: Multi-purpose bucket

Description:
BACKGROUND OF THE INVENTION 
     1. Field of Invention 
     The present invention relates to screening material, and in particular to a particle size separating bucket for earth moving equipment. 
     2. Description of Related Art 
     The requirement for screening aggregate or the like on the site of a construction operation normally requires the use of a separate screen of one form or another. To achieve the required result, a front end loader, backhoe or other earth moving type equipment is used to load the screen and eventually pick-up the screened (separated) material and/or the rejects and move them to their place of utility. 
     At many remote locations, it is often necessary to both excavate material and to provide screened material for the same site. In such locations, it is frequently necessary to excavate the material and remove it from the site with a dump truck or the like. It is also necessary to transport screened material back to the same site for use in construction of roads and the like. Such duplication of equipment and transportation is unnecessary and cost prohibitive for many job sites. Previous attempts to provide equipment that functions, not just as an earth mover but also as a particle screening or separating device have not been suitable. 
     Such previous attempts to provide a screening devices have not enabled the screening apparatus to also function as an excavating bucket. Although previous screens have been utilized on loading buckets, such buckets do not enable the operator to dig substantially below grade as does an excavator bucket. Such devices also require an external power or agitating source such as a vibrator to ensure the material will be passed through the screen. Such vibrators add wear and tear to the device as well as add additional complexity. 
     U.S. Pat. No. 3,072,257 issued Jan. 8, 1963 to Hawkenberry describes a combined gravel collecting and straining system formed in the bucket of an earth mover having a blade, a collecting section and a screen section. The screen section forms part of the floor of the bucket adjacent to the free end of the collecting section, i.e. projecting from the collecting section in the direction away from the blade. In this system, the blade and collecting section combine to pick up the gravel or the like to be screened and then the bucket is oriented to move the material away from the blade section against a dam at the free or leading end of the screening section and onto the screening section. Shaking or otherwise moving the bucket sifts the finer material through the screen. A suitable barricade or dam must be provided at the free end of the extended bucket to prevent the material from simply sliding off the free end of the screen without being screened. There is no appreciable way to dig substantially below grade as the bucket will only load material and not excavate. 
     Two recent U.S. Pat. Nos. 5,311,684 issued May 17, 1994 to Dalfsen and 5,405,092 issued Apr. 11, 1995 to Jonninen, describe systems for scooping and crushing using live elements that are rotated within the scooping element to crush or reduce the particle size before the particles are released. These devices are quite complicated and generally require a dedicated bucket system that is only suitable for use for this purpose. These devices also do not provide a way to excavate material below grade and are. 
     SUMMARY OF THE INVENTION 
     According to a first embodiment of the present invention there is disclosed a multi-configurable bucket for screening material comprising a blade having a bottom edge, a top edge and a connector therebetween for securing to a distal end of the arm of a earth moving equipment. The bucket further comprises a bottom screen having front and rear edges being rotatable about the top edge of the blade section. The bottom screen is positionable so as to extend angled away from the bottom edge of the blade. The bucket further comprises a front screen rotatable relative to the bottom screen having a main screen portion and an angled end-screen portion. The front screen is positionable to a closed position proximate the front edge of the bottom screen such that the front edge of the bottom screen extends past the angled bottom portion of the front screen. 
     The bottom screen may be pivotally connected to the blade proximate to the top edge thereof. The front screen may be pivotally connected to the blade proximate to the top edge thereof. The front screen and bottom screen may be pivotally connected to the blade proximate to the top edge thereof at a common pivot. 
     At the closed position the end screen portion of the front screen may angle towards the blade. At the closed position, the front edge of the bottom screen may extend past the end screen portion of the front screen by at least 6 inches. The main screen portion and end screen portion of the front screen and the bottom screen may form a segmented screening surface. 
     The main screen portion and end screen portion of the front screen and the bottom screen may be angularly oriented relative to each other by angles of greater than 100 degrees. The front screen may be openable so as to permit the blade and bottom screen to excavate soil material. The bottom screen may comprise a substantially planar screening surface supported by opposed side plates. 
     The bottom screen and front screen may be formed of plastic. The bottom screen and front screen may be supported by a plurality of parallel spaced apart tines. The front edge of the bottom screen may extend past the tines of the end screen portion of the front screen by at least 6 inches. 
     Other aspects and features of the present invention will become apparent to those ordinarily skilled in the art upon review of the following description of specific embodiments of the invention in conjunction with the accompanying figures. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In drawings which illustrate embodiments of the invention wherein similar characters of reference denote corresponding parts in each view, 
         FIG. 1  is a side view of an excavator having a bucket according to a first embodiment of the present invention on the end of it&#39;s arm. 
         FIG. 2  is a cross-sectional view of the bucket of  FIG. 1  taken along the line  2 - 2  in a closed position. 
         FIG. 3  is a cross-sectional view of the bucket of  FIG. 1  taken along the line  2 - 2  in an open excavating position. 
         FIG. 4  is a cross-sectional view of the bucket of  FIG. 1  taken along the line  2 - 2  in an open loading position. 
         FIG. 5  is a perspective view of the screen and supporting tines of the bucket of  FIG. 1 . 
         FIG. 6  is a cross-sectional view of the bottom screen of the bucket of  FIG. 1 . 
         FIG. 7  is a cross-sectional view of the bottom screen of  FIG. 6  taken along the line  7 - 7 . 
     
    
    
     DETAILED DESCRIPTION 
     Referring to  FIGS. 1 through 5 , a bucket according to a first embodiment of the invention is shown generally at  10  supported on the end of the articulated arm or boom  8  of an earth moving vehicle  6  or the like. Although the bucket  10  is shown on the end of an excavator arm, it will be appreciated that the bucket may be utilized with other types of earth moving vehicles as well, such as by way of non-limiting example, a loader or a front end loader. The present bucket  10  will enable the operator of the earth moving vehicle  6  to excavate, load, or screen soil material. With reference to  FIGS. 2 through 4 , the bucket  10  comprises a blade  12 , a bottom screen  40  and a front screen  60  pivotally secured to each other to as to be arrangable in a plurality of orientations to suite differing functions. The front screen  60  and bottom screen  40  may be rotated relative to the blade by any conventional arrangement of hydraulic cylinders  13  as are commonly known. 
     The bucket  10  may be mounted on any suitable moving device, such as the arm  8  and in any conventional manner and movable relative to the earth moving vehicle  6  via a hydraulic cylinder(s) or the like. Generally, blade  12  of the bucket  10  is pivotably mounted at the free end of the arm  8  via a pivot connection  9  as are conventionally known. The orientation of the bucket  10  relative to the arm  8  or earth moving vehicle  6  is regulated by a suitable hydraulic cylinder or the like. 
     The blade  12  comprises an elongate body having bottom and top edges,  14  and  16 , respectively and front and rear surfaces,  20  and  22 , respectively. The rear surface  22  includes a connector  24  of a known type for connecting the bucket  10  to the distal end of the arm  8  of a piece of earth moving vehicle  6 . Although a quick coupler type connection is illustrated in the accompanying figures, it will be appreciated that other types of connectors may be utilized as well. The top edge  16  of the blade  12  includes a pivot  18  for pivotally mounting the bottom and front screens  40  and  60 . As illustrated the bottom and front screens  40  and  60  may be pivotally secured to the blade  12  at a common pivot  18 . Alternatively, the bottom and front screens  40  and  60  may be pivotally mounted to the blade about separate pivot mounts. In still further embodiments, the front screen  60  may be pivotally mounted to the bottom screen  40  while the bottom screen is pivotally mounted to the blade  12 . The pivot  18  may comprise a pivot pin or any other known rotatable connector. 
     The bottom screen  40  comprises a substantially planar or segmented screening section  42  having front and rear edges  44  and  46 , respectively. The front and rear edges  44  and  46  may include smooth or toothed digging edges as are commonly known in the art. The bottom screen  40  includes a pair of axial side walls  48 , only one of which is shown in the accompanying figures, one at each side of the bottom screening section  42 . Each side wall  48  includes a top distal end  50  which is pivotally connected to the pivot  18  as described above. The side walls  48  are positioned outside of the blade  12 . 
     As illustrated in  FIG. 6 , the bottom screening section  42  is comprised of a plurality of spaced apart tines or forks  80  extending between the front and rear edges  44  and  46  of the bottom screen  40  having a sheet of screening material  82  secured thereto. The screening material may be a plate of screening material and may be secured to the tines  80  with a suitable clamping mechanism such as by way of non-limiting example, fasteners, overlapping flanges or adhesives. In particular, the screening material  82  may be secured in position by fasteners or the like which have been passed through the plate screening material  82  and screwed into the tines  80 . The heads of these fasteners will preferably be substantially flush with the surface of the screening material  82 . The screening material  82  may comprise a grate or other similar screening structure and may be formed of any suitable material. In particular, it has been found that forming the screening material  82  of plastic such as polyvinyl chloride (PVC), polyethylene, (PE), polycarbonate, cellulose acetate, acrylonitrile butadiene styrene (ABS), acrylic or ultra high molecular weight polyethylene (UHMW) by way of non-limiting example. It will be appreciated that other materials may also be useful as well. 
     The front screen  60  comprises an arcuate member having a proximate end  62  pivotally connected to the blade  12  and a free distal edge  64 . The front screen comprises a plurality of tines  66  supporting a screening panel  68  as shown and described with reference to  FIG. 6  above. The front screen  60  includes a pair of axial side walls  70 , only one of which is shown in the accompanying figures which may be received between the side walls  48  of the bottom screen. As illustrated, the front screen  60  comprises a plurality of segments angularly connected to each other to form the arcuate shape illustrated. The front screen  60  includes a main portion  72  and an end portion  74 , the purpose of which will be more fully described below. The main portion  72  and end portion are angularly connected to each other so as to form a first angle generally indicated at  76  therebetween 
     As illustrated in  FIG. 2 , the bucket  10  may be configured such that the blade  12 , bottom screen  40  and front screen  60  are continuous with each other in a closed or screening configuration. In such a configuration, the bucket  10  may be utilized to screen or sift soil or other material therein. As illustrated, in the screening configuration, the end portion  74  of the front screen  60  and the bottom screen  40  form a second angle generally indicated at  78  therebetween. In the screening configuration, the bucket  10  may be rocked or otherwise cyclically moved back and forth in a rotational motion as indicated generally at  90 . In such a motion, the soil contained within the bucket  10  will be moved back and forth across the bottom and front screen  40  and  60  so as to assist in the bucket in screening the material. The first and second angles should be chose so as to not unduly impede movement of the soil over the screens. In particular, the applicant has found that angles of greater than 100 degrees has been useful for the first and second angles  76  and  78  although it will be appreciated that wider angles will be more useful for allowing movement of material within the bucket. 
     Additionally, in the configuration shown in  FIG. 2 , the bucket  10  may also be utilized for moving soil or forwarding. The exterior of the front screen  60  and the front edge  44  of the bottom screen  40  of the bucket  10  may be engaged against a soil formation and thereafter utilized to push the soil forward in a motion generally indicated at  92 . As illustrated, the bottom portion  74  of the front screen  60  is set back from the front edge  44  of the bottom screen by a setback distance generally indicated at  94 . It will be appreciated that locating the end portion  74  back of the front edge  44  will prevent the tines and screen material of the front screen  60  from being damaged by such a motion as the front edge  44  which is better suited to digging will primarily engage the soil. This will also prevent the tines from becoming jammed and clogged by soil and rock from such a motion. In practice, it has been found that a set back distance of 6 inches has been suitable, although it will be appreciated that other distances may be useful as well. 
     Turning now to  FIG. 3 , the bucket  10  may be utilized for loading by opening the front screen  60  away from the bottom screen  40  and may thereafter be used to scoop material at or above grade as is typically performed by a loader with a loading motion generally indicated at  98 . It will be appreciated, that such a movement may be utilized for conventional loading as well as to fill the bucket  10  with material that is to be screened as illustrated in  FIG. 2 . In such a sequence, after the bucket  10  has been filled, the front screen  60  may be moved to the position showing in  FIG. 2  and thereafter utilized to screen the material as described above. 
     With reference to  FIG. 4 , the bucket  10  may also be utilized in an excavating configuration as shown. In the excavating configuration, the front and bottom screen  60  and  40  are rotated away from the blade  12  and moving the bucket in a downward motion towards the earth moving vehicle  6  as generally indicated at  96 . It will be appreciated, that such a movement may be utilized for conventional loading as well as to fill the bucket  10  with material that is to be screened as illustrated in  FIG. 2 . In such a sequence, after the bucket  10  has been filled, the front screen  60  may be moved to the position showing in  FIG. 2  and thereafter utilized to screen the material as described above. 
     It will be seen that through the use of the bucket  10  of the present description, work can be generated (ie. the bucket filled) in the normal excavating direction as well as in the opposite direction, creating a significant improvement in productivity for an excavator. Conventional excavators only generate work in one direction, by digging toward the excavator. In such an operation, the reaching out movement is only a set up to being able to dig. With the present bucket  10 , material can also be forwarded with closed bucket as described above or loaded by pushing away with the cutting edge of the bottom screen. Utilizing a conventional bucket, the digging or working area is typically at grade (track level) or below. To work a pile above grade the excavator climbs the pile so it can dig below track level. With the use of the above bucket, the excavator may work above grade by front loading or below grade by digging. 
     As illustrated in  FIG. 5 , the bucket  10  may also have the bottom screen  40  rotated away from the blade  12  and the front screen  60  rotated away from the bottom screen  40 . In such a configuration, the bottom screen  40  of the bucket  10  is able to support an elongate object, such as a log  4  or the like longitudinally along the bottom screen such that the blade  12  and the front screen  60  may be engaged upon the top of the log to retain it within the bucket. 
     Turning to  FIG. 7 , a cross-sectional view of the construction of the bottom screen  40  is illustrated according to one embodiment of the present invention. The tines  80  of the bottom screen may extend between front and rear edges  44  and  46  of the bottom screen (only the front edge is illustrated in  FIG. 7 ). As illustrated, the tines may have a bend  83  in the middle thereof. The bend  83  may include a perpendicularly extending middle bar member  84  extending thereacross. The screening material  82  may be comprised of first and second screening panels  82   a  and  82   b  located between the middle bar member  84  and their respective end of the bottom screen. The bucket  10  may also include a retaining bar  85  comprising an elongate flat bar  86  having wedges  87  extending from the bottom thereof. The wedges  87  are spaced apart by a distance sufficient for them to be frictionally fitted between the first or second screening member  82   a  or  82   b  and the middle bar member  84 . The resulting frictional fit will retain the flat bar  86  above the edge of the screening member and therefore retain it against the tines  80 . The other end of the screening member may be retained by a lip  88  or other suitable means on the front or rear edge  44  or  46 . Utilizing the above method, it has been found that screening members formed of machined 1 inch thick UHMW material has been satisfactory although other material types and thicknesses may be useful as well. 
     The front screen  60  may be similarly formed as described above for the bottom screen. Alternatively, the front screen may be formed of a thicker material of up to 2 inches or more and retained in place with fasteners which extend through the screening member and the tines, such as by way of non-limiting example, clavicles, clamps or the like. 
     While specific embodiments of the invention have been described and illustrated, such embodiments should be considered illustrative of the invention only and not as limiting the invention as construed in accordance with the accompanying claims.