Patent Publication Number: US-2007122262-A1

Title: Grapple attachment

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
      This application is a continuation of U.S. patent application Ser. No. 10/840,005 filed on May 6, 2004, which claims priority from U.S. Provisional Patent Application No. 60/468,315 filed May 6, 2003. 
    
    
     BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention relates to a device for gripping, moving and handling materials and, more particularly, to a fork and jaw grapple for operatively attaching to a skid steer loader or other equipment.  
      2. Related Art  
      It is known to provide various grapple attachments for securing to skid steer loaders and other equipment. Grapple buckets, slab grabbers, grapple rakes, industrial grapples, box rakes, landscape rakes, power rakes, land planes, planers, demolition attachments, quick-tach grapples, jack buckets, shaker buckets, scrap grapples, pallet forks, root grapples, brooms, back fillers, chippers and snow blades are examples of various attachments for skid steer loaders. A significant disadvantage with these attachments is that the attachments are designed for a very specific purpose and are not multi-functional.  
      An owner of a skid steer loader desires an attachment that is multi-functional. For example, an owner may use a skid loader to, among other things, lift and transport 55-gallon drums; to scoop, lift, transport and dump sod; and to lift, transport and dump logs, telephone poles or slabs of concrete. A single attachment could not perform all of these tasks efficiently and effectively. The cost for purchasing an attachment for each task is prohibitive. It would be much more beneficial to have an attachment for perform multiple tasks, such as lifting and transporting logs, pipes, boards, tires, stumps, concrete slabs, rocks, scrap metal, barrels and other materials.  
      Moreover, storing multiple attachments is not desirable because of the storage area required to store these attachments. Additionally, leaving the attachments outside significantly reduces the performance and life of the attachments.  
      The process of removing concrete slabs from sidewalks, foundations, flooring or other areas (hereinafter collectively “concrete slabs”) is problematic. First, the concrete slabs need to be pried loose from the ground surface. This is not easily done because the attachments available for a skid steer loader are not designed for this purpose. Most attachments are bucket shaped and too big and awkward to efficiently remove concrete.  
      The process of placing materials into a dump truck or other vehicles with a skid steer loader is also problematic because the attachments drop the materials into the back of the dump truck. For example, concrete slabs that are pried loose and picked up with the bucket attachment of a skid steer loader have to be dropped into the dump truck. Dropping heavy pieces of materials into the back of a dump truck creates significant safety risks and causes damage to the dump truck. Moreover, if the operator of the dump truck owns the rig, the operator may become agitated and angry when heavy loads are dumped into the back of the dump truck. There is a need for an attachment that can place various materials into the back of a dump truck.  
      Using a skid steer loader to place materials into a dump truck without damaging the materials is problematic. For example, piping that cannot be dented or damaged is usually dropped from the bucket attachment of a skid steer loader into the back of a dump truck. The probability of damaging materials that are dropped into a dump truck is high.  
     SUMMARY OF THE INVENTION  
      An aspect of the present invention is to provide an apparatus for overcoming one or more of the problems set forth above.  
      Another aspect of the invention is to provide a fork and jaw grapple that efficiently pries loose concrete slabs.  
      In another aspect of the invention there is provided a fork and jaw grapple that holds and transports concrete slabs and places the concrete slabs into a desired location, such as the back of a dump truck, without dropping said materials.  
      In one aspect of this invention there is provided a multi-purpose grapple for performing multiple tasks including but not limited to lifting and transporting logs, pipes, boards, tires, stumps, concrete slabs, rocks, scrap metal, barrels and other materials and placing the materials in a desired location without dropping said materials.  
      In still another aspect of this invention there is provided a multi-purpose grapple for performing multiple tasks including but not limited to placing logs, pipes, boards, tires, stumps, concrete slabs, rocks, scrap metal, barrels and other materials in a desired location without dropping to avoid damaging said materials.  
      In yet another aspect of the invention there is provided a multi-purpose grapple for performing multiple tasks including but not limited to placing logs, pipes, boards, tires, stumps, concrete slabs, rocks, scrap metal, barrels and other materials into a device, such as the back of a dump truck, without damaging said device.  
      Thus, in furtherance of the above goals and advantages, the present invention is, briefly, a grapple attachment. The grapple attachment has at least one lower fork, an upper jaw pivotably connected to the lower fork(s), and a hydraulic cylinder operatively connected to the upper jaw. The hydraulic cylinder is adapted to pivot the upper jaw relative to the lower fork(s). The lower fork(s) has a longitudinally extending member with an arcuate portion located at an end portion of the longitudinally extending member such that the arcuate portion provides a fulcrum point and the longitudinally extending member provides a lever for mechanical advantage.  
      Further, the present invention is, briefly, a fork and jaw grapple attachment for a machine. The fork and jaw grapple attachment has a first lower fork, a second lower fork spaced apart from the first lower fork, an upper jaw pivotably connected to the first lower fork and the second lower fork, and a hydraulic cylinder operatively connected to the upper jaw. The hydraulic cylinder is adapted to pivot the upper jaw relative to the first lower fork and the second lower fork. The first lower fork has a longitudinally extending member with an arcuate portion located at an end portion of the longitudinally extending member such that the arcuate portion provides a fulcrum point and the longitudinally extending member provides a lever for mechanical advantage. The second lower fork also has an arcuate portion located at an end portion of the longitudinally extending member such that the arcuate portion provides a fulcrum point and the longitudinally extending member provides a lever for mechanical advantage.  
      These, and other aspects and advantages of the present invention, will become apparent from the following detailed description. The above listing of aspects of the invention should not be deemed as all-inclusive in any manner whatsoever.  
      Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.  
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein:  
      The accompanying drawings, which are incorporated in and form a part of the specification, illustrate the embodiments of the present invention and together with the description, serve to explain the principles of the invention. In the drawings:  
       FIG. 1  is a side view of a fork and jaw grapple according to the present invention;  
       FIG. 2  is a front view of the fork and jaw grapple according to  FIG. 1 ;  
       FIG. 3  is a top view of the fork and jaw grapple according to  FIG. 1 ;  
       FIG. 4  is a back view of the fork and jaw grapple according to  FIG. 1 ;  
       FIG. 5  is a side view of the fork and jaw grapple showing a cross-sectional view of the jaw according to  5 - 5  of  FIG. 3 ;  
       FIG. 6  is a side view of the fork and jaw grapple showing a cross-sectional view of the fork according to  6 - 6  of  FIG. 3 ; and  
       FIG. 7  is a side view of a skid steer loader. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
      The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.  
      Referring to the accompanying drawings in which like reference numbers indicate like elements,  FIGS. 1-6  illustrate a fork and jaw grapple  10  for use on a vehicle, for example a skid steer loader  100  (see  FIG. 7 ). The fork and jaw grapple  10  has two forks  11  and a jaw  12 . In alternative embodiments, there could be additional forks  11  and jaws  12 . The forks  11  and jaw  12  are made from high strength steel. Tips  13  of the forks  11  are preferably made of high carbon steel.  
      In the depicted embodiment, the forks  11  are L-shaped and operatively attached to each other via a middle section  14 . The forks  11  are preferably spaced thirteen and one-eight (13⅛th) inches apart from each other and have a width from outer edge to outer edge of twenty-six (26) inches. In the fork and jaw grapple&#39;s  10  resting position as shown in  FIGS. 1, 5  and  6 , the forks  11  extend parallel with a horizontal plane for approximately seventeen and one-half (17½) inches from back surfaces  16  of upward extending members  15  of the forks  11 . Thereafter, the forks  11  have curvatures  17  which are used for prying and getting under heavy objects. The curvatures  17  extend approximately eighteen and one-half (18½) inches. There is a twenty-two (22°) degree angle between a tapered portion  21  of the forks  11  and horizontal plane or bottom surfaces  19  of the forks  11 . The back surfaces  16  of the upward extending members  15  are eighty-three (83°) degrees from the bottom surfaces  19  of the forks  11 . The forks  11  are thirty-six (36) inches in length from the back surfaces  16  of the upward extending members  15  to ends of the forks  11 . Each of the upward extending members  15  have at least one stop  18  for precluding upward movement of objects being carried or moved by the fork and jaw grapple  10 . The stops  18  are approximately six and three-fourths (6¾th) inches from top surfaces  20  of the forks  11 . The curvatures  17  and shape of the forks  11  magnify the “breakout” or upward force that can be exerted by the fork and jaw grapple  10 . This is significant because a skid steer loader is limited in the amount of upward force it can apply on an object. The width of the fork and jaw grapple  10  is narrower than a full-length or width bucket attachment commonly used on a skid steer loader so that the forks  11  are within the width of concrete slabs to facilitate the prying up and carrying of concrete slabs. The narrowness of the fork and jaw grapple  10  is important, significant and advantageous over a full-length or width bucket attachment because it concentrates the limited effort of the skid steer loader in front of and close to the center line of the machine. Moreover, the narrower width allows the skid steer loader to maneuver in tight spots. For example, the skid steer loader with the fork and jaw grapple  10  attached thereto enables the operator to steer or track straight in and out in-line with a slab of concrete for a sidewalk. This allows efficient removal of concrete slabs with minimal disruption to the surroundings. In contrast, when a full-length or width bucket is used to removed a slab of concrete from a sidewalk, the corner of a bucket would be used to pry up the slab which commonly leads to equipment failure and defect and significant disruption of the surrounding soil and concrete. As examples, the fork and jaw grapple  10  may have a width less than the width of a machine frame, a width less than four feet, or a width less than three feet. It should be noted that the previously described dimensions of the fork and jaw grapple  10  are beneficial for maneuvering, prying up and carrying concrete slabs and other materials; however, the dimensions may be varied.  
      The middle section  14  is L-shaped and operatively connected between the forks  11 . The middle section  14  terminates on the horizontal plane with a U-shaped section  22 . The U-shaped section  22  is preferable over other shapes because it is free of pinch points and will not grab the materials or objects being lifted. In the preferred embodiment, the middle section  14  terminates approximately twelve (12) inches from a front surface  23  of the upward extending members  15 .  
      Referring now to  FIGS. 1, 5  and  6 , the jaw  12  is a hydraulically actuated upper jaw and moves about a pivot point  24  via a cylinder  25 . The jaw  12  has a range of motion about the pivot point  24 . The jaw  12  has an arm  34  having a straight portion  35  and a curved end  36 . The curved end  36  curves downwardly when in the resting position. The curved end  36  facilitates the grabbing or holding of materials or objects and precludes materials or objects from slipping out of the fork and jaw grapple  10  during transport. The jaw  12  moves about the pivot point  24  and provides a holding or clamping force on materials or objects. The straight portion  35  of the arm  34  has fingers  37  for gripping and holding materials or objects.  
      The cylinder  25  has a three (3) inch bore diameter and twelve (12) inch stroke length. The cylinder  25  is housed in a shroud  38  to protect it from damage during use and inclement weather. The shroud  38  is operatively connected to the jaw  12 . The cylinder  25  has a first end  27  operatively connected to a first horizontal pin  26 , and a second end  29  operatively connected to a second horizontal pin  28 . The first horizontal pin  26  is rotatably mounted to a back mounting bracket  30 , and the second horizontal pin  28  is rotatably mounted to a front mounting bracket  31 . The front mounting bracket  31  is operatively mounted to a front, top end  32  of the jaw  12 . The back mounting bracket  30  is operatively attached to the middle section  14  at a top portion  33 . The pivot point  24  of the jaw  12  is offset from the first horizontal pin  26  of the cylinder  25  in the vertical and horizontal axis, and the second horizontal pin  28  is offset from the pivot point  24  and the first horizontal pin  26  in the vertical and horizontal axis such that when the cylinder extends and retracts, the jaw  12  rotates about the first horizontal pin  26  as indicated by the phantom lines in  FIG. 1 . Specifically, as the second end  29  of the cylinder  25  extends, the jaw  12  moves or pivots about the pivot point  24  in the downward direction towards the forks  11 , and as the second end  29  of the cylinder  25  retracts, the jaw  12  moves or pivots about the pivot point  24  in the upward direction away from the forks  11 .  
      In one embodiment, the present invention is a fork and grapple attachment for a machine having a machine frame. The fork and jaw grapple attachment includes a first lower fork, a second lower fork spaced apart from the first lower fork, a middle section rigidly connected to the first lower fork and to the second lower fork, an upper jaw pivotably connected to the first lower fork and to the second lower fork, and a hydraulic cylinder operatively connected to the upper jaw. The upper jaw includes an arm having an arcuate end portion at a distal end of the arm. The first lower fork has a longitudinally extending member, an upwardly extending back member transverse to the longitudinally extending member, an arcuate portion located at an end portion of the longitudinally extending member, and a tapered portion operatively connected to the arcuate portion. The second lower fork also has a longitudinally extending member, an upwardly extending back member transverse to the longitudinally extending member, an arcuate portion located at an end portion of the longitudinally extending member, and a tapered portion operatively connected to the arcuate portion. A width between an outside edge of the first lower fork and an outside edge of the second lower fork is less than the width of the machine frame.  
      In another embodiment, the present invention is a fork and grapple attachment for a machine having a machine frame. The fork and jaw grapple attachment includes a first lower fork, a second lower fork spaced apart from the first lower fork, a middle section rigidly connected to the first lower fork and to the second lower fork, an upper jaw pivotably connected to the first lower fork and to the second lower fork, and a hydraulic cylinder operatively connected to the upper jaw. The upper jaw includes an arm having an arcuate end portion at a distal end of the arm. The first lower fork has a longitudinally extending member, an upwardly extending back member transverse to the longitudinally extending member, an arcuate portion located at an end portion of the longitudinally extending member, and a tapered portion operatively connected to the arcuate portion such that the arcuate portion provides a fulcrum point and the longitudinally extending member provides a lever for mechanical advantage. The second lower fork also has a longitudinally extending member, an upwardly extending back member transverse to the longitudinally extending member, an arcuate portion located at an end portion of the longitudinally extending member, and a tapered portion operatively connected to the arcuate portion such that the arcuate portion provides a fulcrum point and the longitudinally extending member provides a lever for mechanical advantage. A width between an outside edge of the first lower fork and an outside edge of the second lower fork is dimensioned for operative engagement with a slab of concrete for a sidewalk. However, the width may be dimensioned such that the slab of concrete can be removed from the ground without disrupting a significant amount of sod adjacent the concrete slab.  
      In yet another embodiment, the present invention is a skid steer loader having a machine frame. The skid steer loader includes an attachment. The attachment includes a first lower fork, a second lower fork spaced apart from the first lower fork, a middle section rigidly connected to the first lower fork and to the second lower fork, an upper jaw pivotably connected to the first lower fork and to the second lower fork, and a hydraulic cylinder operatively connected to the upper jaw. The upper jaw includes an arm having an arcuate end portion at a distal end of the arm. The first lower fork has a longitudinally extending member, an upwardly extending back member transverse to the longitudinally extending member, an arcuate portion located at an end portion of the longitudinally extending member, and a tapered portion operatively connected to the arcuate portion. The second lower fork also has a longitudinally extending member, an upwardly extending back member transverse to the longitudinally extending member, an arcuate portion located at an end portion of the longitudinally extending member, and a tapered portion operatively connected to the arcuate portion. A width between an outside edge of the first lower fork and an outside edge of the second lower fork is less than the width of the machine frame.  
      In use, the skid steer loader can move the fork and jaw grapple  10  in the vertical and horizontal direction. In addition, the skid steer loader can move the fork and jaw grapple  10  from its resting position shown in  FIGS. 1, 5  and  6  approximately ninety (90°) degrees clockwise or ninety (90°) degrees counterclockwise.  
      In one such use, the fork and jaw grapple  10  can be used to pry concrete slabs upward away from the ground without removing a significant amount of sod. When above the concrete slab to be removed, the fork and jaw grapple  10  is rotated ninety (90°) degrees counterclockwise or downward so that a mouth  40  of the fork and jaw grapple  10  is pointing downward toward the concrete slab. Thereafter, the forks  11  of the fork and jaw grapple  10  wedge between concrete slabs and are then the fork and jaw grapple  10  is rotated ninety (90°) clockwise or upward and slid under the concrete slab to pry it from the ground. The angle at the tips  13  of the forks  11  and the forces being applied by the skid steer loader and the fork and jaw grapple  10  facilitate the “breakout” or prying away of the concrete slab from the ground. The fork and grapple  10  is able to remove concrete slabs without removing a significant amount of sod, which is in contrast to the bucket attachment which removes a large amount of sod when performing the same operation. The fork and jaw grapple  10  is then used to fully slip the forks  11  under the concrete slab at which time the second end  29  of the cylinder  25  is extended causing the jaw  12  to move downward into engagement and to hold or grab the concrete slab. The stops  18  prevent the concrete slab from moving upward past the stops  18 . The fork and jaw grapple  10  is then used to pick-up and transport the concrete slab to a dump truck, other vehicle or location for place down into the back of the dump truck, other vehicle or location as opposed to dumping the concrete slab into the back of the dump truck, other vehicle or location. When above the back of the dump truck, other vehicle or location, the fork and jaw grapple  10  is rotated ninety (90°) degrees counterclockwise or downward so that the mouth  40  of the fork and jaw grapple  10  holding or grasping the concrete slab is pointing downward. Thereafter, the fork and jaw grapple  10  places the concrete slab in contact with the back of the dump truck, other vehicle or location, and the second end  29  of the cylinder  25  retracts thereby opening the jaw  12  to release the concrete slab. Because the concrete slab is not dumped or dropped, the dump truck or other vehicle is not damaged.  
      In other uses, the fork and jaw grapple  10  is slid under or into materials, such as telephone poles, pipes, posts, railroad ties, tires, scrap piles or other materials or objects. The angle at the tips  13  of the forks  11  and the forces being applied by the skid steer loader and the fork and jaw grapple  10  facilitate the insertion under or into the materials. After insertion under or into these materials, second end  29  of the cylinder  25  is extended thereby moving the jaw  12  downward into engagement and to hold the materials during pick-up, transport or placement down. The fork and jaw grapple  10  is then used to pick-up and transport the materials to a dump truck, other vehicle or location for placing down, as opposed to dumping the materials. When above the back of the dump truck, other vehicle or location, the fork and jaw grapple  10  is rotated ninety (90°) degrees counterclockwise or downward so that the mouth  40  of the fork and jaw grapple  10  holding or grasping the materials is pointing downward. Thereafter, the fork and jaw grapple  10  places the materials in contact with the back of the dump truck, other vehicle or location, and the second end  29  of the cylinder  25  retracts thereby opening the jaw  12  to release the materials. Because the materials are not dumped or dropped, the materials are not damaged during handling.  
      In other uses, the fork and jaw grapple  10  slides under, grabs or holds (as previously explained) and lifts rocks, barrels, tires and other similar objects. Thereafter, the fork and jaw grapple  10  places the object in contact with the back of the dump truck, or other location, and the second end  29  of the cylinder  25  retracts thereby opening the jaw  12  to release the object.  
      A method of assembling a fork and jaw grapple is also disclosed. The method includes the steps of: providing a first lower fork, locating a second lower fork spaced apart from the first lower fork such that a width between an outside edge of the first lower fork and an outside edge of the second lower fork is dimensioned for operative engagement with a slab of concrete for a sidewalk, rigidly connecting a middle section to the first lower fork and to the second lower fork, pivotably connecting an upper jaw to the first lower fork and to the second lower fork, and operatively connecting a hydraulic cylinder to the upper jaw.  
      The present invention also includes a method of using a fork and jaw grapple. The method includes the steps of: providing a fork and jaw grapple, moving the fork and jaw grapple toward the slab of concrete, engaging the first lower fork and the second lower fork with a bottom side of the slab of concrete, prying upwardly the slab of concrete, engaging the upper jaw with the slab of concrete, and lifting upwardly the slab of concrete. Optionally, the method may further include the step of placing the concrete slab into a back of a vehicle.  
      In view of the foregoing, it will be seen that the several advantages of the invention are achieved and attained.  
      As various modifications could be made in the constructions and methods herein described and illustrated without departing from the scope of the invention, it is intended that all matter contained in the foregoing description or shown in the accompanying drawings shall be interpreted as illustrative rather than limiting. For example, while in the depicted embodiments there is a single upper jaw, those skilled in the art will understand that the fork and jaw grapple may include two or more upper jaws. Thus, the breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims appended hereto and their equivalents.