Abstract:
A tractor attachment mountable on a loader boom of a tractor and a tractor attachment kit. In one embodiment, the tractor attachment is a grapple assembly, and the grapple assembly kit includes a mounting assembly, a plurality of clamping units, and a plurality of support units. The clamping units and the support units are removably mountable on the mounting assembly and may be arranged in different combinations on the mounting assembly. Such combinations may range from a single clamping unit mounted on the mounting assembly to a mixture of clamping units and support units mounted on the mounting assembly to several clamping units mounted on the mounting assembly. The clamping units may have alternative pivot points to permit jaws of the clamping unit to close at different speeds and with different forces. One or more fangs may be removably mounted on a clamping unit to enhance its grip.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present application claims the benefit under 35 U.S.C. 119(e) of U.S. Provisional Patent Application No. 62/136,661, filed Mar. 23, 2015, the disclosure of which is incorporated herein by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    The present invention relates generally to tractor attachments and relates more particularly to a novel tractor attachment and to a tractor attachment kit. 
         [0003]    Tractors are powerful motor vehicles commonly used in, for example, agriculture, landscaping, and construction to perform a variety of moving, lifting and other tasks. To perform such tasks, various types of specialized attachments are typically coupled to the tractor. One such specialized tractor attachment is a bucket, the bucket being coupled to the front end of the tractor using an assembly commonly referred to as a loader boom. One common type of loader boom comprises a pair of arms and a pair of mounts. The rear end of each arm is pivotally mounted on the tractor, and a mount is pivotally mounted on the front end of each arm. The bucket, in turn, is typically mechanically coupled to the pair of mounts. Pivotal movement of the arms relative to the tractor is typically provided by a first hydraulic mechanism, and pivotal movement of the mounts relative to the arms is typically provided by a second hydraulic mechanism. In this manner, the bucket may be raised or lowered by operation of the first hydraulic mechanism, and the bucket may be angularly adjusted by operation of the second hydraulic mechanism. 
         [0004]    Referring now to  FIGS. 1 and 2 , there are shown a front, perspective view and an enlarged, fragmentary, rear, perspective view of an exemplary conventional tractor assembly, the exemplary conventional tractor assembly being represented generally by reference numeral  11 . 
         [0005]    Tractor assembly  11 , which is commercially available from Deere &amp; Company (Moline, Ill.), comprises a tractor  13 . Although tractor  13  is depicted in  FIG. 1  as a four-wheeled motor vehicle, it is to be understood that tractor  13  need not be a four-wheeled motor vehicle and may, instead, comprise other types of vehicles. 
         [0006]    Tractor assembly  11  additionally comprises a bucket  15 . 
         [0007]    Tractor assembly  11  further comprises a loader boom  17 . Loader boom  17 , which is also shown separately in  FIG. 3( a ) , comprises a pair of arms  19 - 1  and  19 - 2  and a pair of mounts  21 - 1  and  21 - 2 . Arms  19 - 1  and  19 - 2  are pivotally mounted at their respective rear ends on tractor  13 . Pivotal movement of arms  19 - 1  and  19 - 2  relative to tractor  13  may be provided by a first hydraulic mechanism comprising one or more hydraulic cylinders  23 . Mounts  21 - 1  and  21 - 2  are pivotally mounted on the front ends of arms  19 - 1  and  19 - 2 , respectively. Pivotal movement of mounts  21 - 1  and  21 - 2  relative to arms  19 - 1  and  19 - 2  may be provided by a second hydraulic mechanism comprising one or more hydraulic cylinders  25 . Bucket  15  is mechanically coupled to mounts  21 - 1  and  21 - 2 . Such coupling is typically achieved by hooks on the rear of bucket  15  that matingly fit over the top ends  23 - 1  and  23 - 2  of mounts  21 - 1  and  21 - 2 , respectively, and by pins extending from the rear of bucket  15  that are received in pin holes  27 - 1  and  27 - 2  in mounts  21 - 1  and  21 - 2 , respectively (one such hook  29  and one such pin  31  being shown in  FIG. 2 ). 
         [0008]    The particulars of the loader boom, as well as the complementary structure on the bucket for attaching to the front end of the loader boom, tend to vary from one manufacturer to another. An example of an alternative conventional loader boom is shown in  FIG. 3( b )  and is represented generally by reference numeral  35 . Loader boom  35  is similar in certain respects to loader boom  17  and comprises a pair of arms  37 - 1  and  37 - 2  that are adapted to be pivotally mounted at their respective rear ends on tractor  13 . Pivotal movement of arms  37 - 1  and  37 - 2  relative to tractor  13  may be effected by a mechanism similar to that used to move arms  19 - 1  and  19 - 2  of loader boom  17 . Loader boom  35  differs principally from loader boom  17  in that loader boom  35  does not include mounts  21 - 1  and  21 - 2  and, instead, includes a plurality of pins  39 - 1  through  39 - 4 . Pins  39 - 1  and  39 - 2  are adapted to couple arms  37 - 1  and  37 - 2 , respectively, to a bucket (not shown) by being inserted through plates  41 - 1  and  41 - 2  on arm  37 - 1  and through plates  41 - 3  and  41 - 4  on arm  37 - 2 , respectively, as well as through corresponding plates (not shown) that are fixedly mounted on the bucket. Pins  39 - 3  and  39 - 4  are adapted to couple the movable ends  45 - 1  and  45 - 2  of hydraulic cylinders  43 - 1  and  43 - 2 , respectively, to the bucket by being inserted through ends  45 - 1  and  45 - 2 , as well as through the aforementioned plates that are fixedly mounted on the bucket. Fasteners  47 - 1  through  47 - 4  may be used to retain pins  39 - 1  through  39 - 4 , respectively, in place. 
         [0009]    As can be appreciated, there are situations in which it would be desirable to replace the functionality afforded by a bucket with the functionality afforded by another type of tractor attachment. As can also be appreciated, it would also be desirable to enable such a replacement to be made without requiring that changes be made to the loader boom. In other words, it would be desirable for the replacement attachment to be attachable to a conventional loader boom. Although some such replacement attachments exist, some of these replacement attachments suffer from certain shortcomings in terms of cost, weight, size, and/or variability in use. 
       SUMMARY OF THE INVENTION 
       [0010]    It is an object of the present invention to provide a novel tractor attachment. 
         [0011]    According to a preferred feature of the invention, the tractor attachment as described above is a grapple assembly. 
         [0012]    According to a preferred feature of the invention, the grapple assembly as described above is capable of being used with, but is not limited to being used with, a conventional loader boom mounted on a tractor. 
         [0013]    According to another preferred feature of the invention, the grapple assembly as described above is a capable of being used in a plurality of different speed/force modes, such as a slower closing mode with a higher clamping force or a faster closing mode with a lower clamping force, and/or is capable of being used in a plurality of different size modes, such as a compact mode with individual grapple components disposed adjacent to or in contact with one another or an expanded mode with individual grapple components spaced apart from one another. 
         [0014]    According to yet another preferred feature of the invention, the grapple assembly as described above overcomes at least some of the shortcomings of existing grapple attachments, such existing grapple attachments tending to be expensive, heavy, bulky, and lacking variability in use. 
         [0015]    It is another object of the present invention to provide a novel tractor attachment kit. 
         [0016]    According to a preferred feature of the invention, the kit as described above is a grapple assembly kit. 
         [0017]    According to another preferred feature of the invention, the grapple assembly kit is capable of being assembled in a plurality of different ways, such as with different combinations of clamping and support components and/or with the same combination of clamping and/or support components arranged in different ways and/or with certain grapple components being operated in different speed/force modes. 
         [0018]    According to one aspect of the invention, there is provided a tractor attachment mountable on a tractor loader boom, the tractor attachment comprising (a) a mounting assembly, the mounting assembly being removably mountable on the tractor loader boom; and (b) a clamping unit, the clamping unit being removably mounted on the mounting assembly, the clamping unit comprising an upper jaw and a lower jaw, the upper jaw being pivotally mounted on the lower jaw, the clamping unit further comprising means for moving the upper jaw relative to the lower jaw. 
         [0019]    In another, more detailed feature of the invention, the upper jaw may be pivotally mounted on the lower jaw at one of a plurality of alternative pivot points. 
         [0020]    In another, more detailed feature of the invention, the plurality of alternative pivot points may comprise a first pivot point and a second pivot point, the first pivot point producing a faster closing speed, the second pivot point producing a greater clamping force. 
         [0021]    In another, more detailed feature of the invention, the clamping unit may further comprise at last one fang, the at least one fang being removably mounted on the upper jaw. 
         [0022]    In another, more detailed feature of the invention, the mounting assembly may comprise a frame, the frame may comprise first and second rails and first and second brackets, the first and second brackets may interconnect the first and second rails and may have structure complementary to the tractor loader boom, and the clamping unit may be removably mounted on the first and second rails. 
         [0023]    In another, more detailed feature of the invention, the tractor attachment may further comprise a lock for removably securing the clamping unit on the mounting assembly. 
         [0024]    In another, more detailed feature of the invention, the mounting assembly may comprise a rail, the rail may have a notch, the clamping unit may comprise an opening, the opening may be aligned with the notch, and the lock may comprise a first member and a second member, the first member and the second member being generally perpendicular to one another, the first member extending through the notch and through the opening, the second member extending downwardly between the rail and the clamping unit. 
         [0025]    According to another aspect of the invention, there is provided a tractor attachment kit for use in assembling a tractor attachment mountable on a tractor loader boom, the tractor attachment kit comprising (a) a mounting assembly, the mounting assembly being removably mountable on the tractor loader boom; and (b) a first clamping unit, the first clamping unit being removably mountable on the mounting assembly, the first clamping unit comprising an upper jaw and a lower jaw, the upper jaw being pivotally mounted on the lower jaw, the first clamping unit further comprising means for moving the upper jaw relative to the lower jaw. 
         [0026]    In another, more detailed feature of the invention, the tractor attachment kit may further comprise a second clamping unit, the second clamping unit may be removably mountable on the mounting assembly, the second clamping unit may comprise an upper jaw and a lower jaw, the upper jaw may be pivotally mounted on the lower jaw, and the second clamping unit may further comprise means for moving the upper jaw relative to the lower jaw. 
         [0027]    In another, more detailed feature of the invention, the mounting assembly may be sized to permit the first clamping unit and the second clamping unit to be concurrently mounted thereon. 
         [0028]    In another, more detailed feature of the invention, the tractor attachment kit may further comprise a first support unit, and the first support unit may be removably mountable on the mounting assembly. 
         [0029]    In another, more detailed feature of the invention, the mounting assembly may be sized to permit the first clamping unit and the support unit to be concurrently mounted thereon. 
         [0030]    In another, more detailed feature of the invention, the tractor attachment kit may further comprise a second clamping unit and a third clamping unit, the second and third clamping units may be identical to the first clamping unit, the tractor attachment kit may further comprise a first support unit and a second support unit, the first and second support units may be identical to one another, each of the first and second support units may be removably mountable on the mounting assembly, and the mounting assembly may be sized to permit up to a threesome of clamping units and/or support units to be concurrently mounted thereon. 
         [0031]    In another, more detailed feature of the invention, the tractor attachment kit may further comprise a pair of forklift tines removably mountable on the mounting assembly. 
         [0032]    According to yet another aspect of the invention, there is provided a tractor attachment mountable on a tractor loader boom, the tractor attachment comprising (a) a mounting assembly, the mounting assembly being removably mountable on the tractor loader boom; (b) a first clamping unit, the first clamping unit being removably mounted on the mounting assembly, the first clamping unit comprising an upper jaw and a lower jaw, the upper jaw being pivotally mounted on the lower jaw, the first clamping unit further comprising means for moving the upper jaw relative to the lower jaw; and (c) one of a second clamping unit and a first support unit removably mounted on the mounting assembly, the second clamping unit comprising an upper jaw and a lower jaw, the upper jaw being pivotally mounted on the lower jaw, the second clamping unit further comprising means for moving the upper jaw relative to the lower jaw. 
         [0033]    In another, more detailed feature of the invention, the second clamping unit may be removably mounted on the mounting assembly. 
         [0034]    In another, more detailed feature of the invention, a third clamping unit may be removably mounted on the mounting assembly, the third clamping unit may comprise an upper jaw and a lower jaw, the upper jaw may be pivotally mounted on the lower jaw, and the third clamping unit may further comprise means for moving the upper jaw relative to the lower jaw. 
         [0035]    In another, more detailed feature of the invention, the first support unit may be removably mounted on the mounting assembly. 
         [0036]    In another, more detailed feature of the invention, a second support may be removably mounted on the mounting assembly. 
         [0037]    In another, more detailed feature of the invention, the tractor attachment may further comprise the second clamping unit removably mounted on the mounting assembly. 
         [0038]    The present invention is also directed to a method of assembling and disassembling a tractor attachment and to a method of using the tractor attachment kit described herein to reversibly assemble a tractor attachment. 
         [0039]    Additional objects, as well as aspects, features and advantages, of the present invention will be set forth in part in the description which follows, and in part will be obvious from the description or may be learned by practice of the invention. In the description, reference is made to the accompanying drawings which form a part thereof and in which is shown by way of illustration various embodiments for practicing the invention. The embodiments will be described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized and that structural changes may be made without departing from the scope of the invention. The following detailed description is, therefore, not to be taken in a limiting sense. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0040]    The accompanying drawings, which are hereby incorporated into and constitute a part of this specification, illustrate various embodiments of the invention and, together with the description, serve to explain the principles of the invention. In the drawings wherein like reference numerals represent like parts: 
           [0041]      FIG. 1  is a front, perspective view of a conventional tractor assembly; 
           [0042]      FIG. 2  is an enlarged, fragmentary, rear, perspective view of the conventional tractor assembly of  FIG. 1 ; 
           [0043]      FIG. 3( a )  is an enlarged, front, perspective view of the loader boom shown in  FIG. 1 , with certain components not being shown for the sake of clarity; 
           [0044]      FIG. 3( b )  is an alternative conventional loader boom to the conventional loader boom shown in  FIGS. 1, 2, and 3 ( a ); 
           [0045]      FIG. 4  is a perspective view of a first embodiment of a grapple assembly kit constructed according to the present invention; 
           [0046]      FIGS. 5( a ) through 5( g )  are front perspective, rear perspective, front, rear, top, right side, and exploded perspective views, respectively, of the mounting assembly shown in  FIG. 4 ; 
           [0047]      FIGS. 6( a )  and through  6 ( c ) are front perspective, right side, and partly exploded perspective views, respectively, of one of the clamping units shown in  FIG. 4 , the clamping unit being shown in  FIGS. 6( a ) and 6( b )  in a closed state and with the upper and lower jaws of the clamping unit being coupled together in a first manner that results in a comparatively faster closing of the jaws with a comparatively lower clamping force; 
           [0048]      FIGS. 7( a ) and 7( b )  are side and rear perspective views, respectively, of the clamping unit shown in  FIGS. 6( a ) through 6( c ) , the clamping unit being shown in completely open and partially open states, respectively; 
           [0049]      FIGS. 8( a ) and 8( b )  are front perspective and exploded perspective views, respectively, of the lower jaw of the clamping unit shown in  FIGS. 6( a ) through 6( c ) ; 
           [0050]      FIGS. 9( a ) and 9( b )  are front perspective and exploded perspective views, respectively, of the upper jaw of the clamping unit shown in  FIGS. 6( a ) through 6( c ) ; 
           [0051]      FIGS. 10( a ) and 10( b )  are right side views, showing the clamping unit of  FIGS. 6( a ) through 6( c )  after it has been configured so that the upper and lower jaws of the clamping unit are coupled together at an alternative pivot point to cause a comparatively slower closing of the jaws with a comparatively higher clamping force than that of  FIGS. 6( a ) through 6( c ) , the clamping unit shown in an open state in  FIG. 10( a )  and in a closed state in  FIG. 10( b ) ; 
           [0052]      FIGS. 10( c ) and 10( d )  are fragmentary right perspective and fragmentary left perspective views, respectively, of an alternative clamping unit to the clamping unit shown in  FIGS. 6( a ) through 6( c ) ; 
           [0053]      FIGS. 11( a ) and 11( b )  are front perspective and exploded perspective views, respectively, of one of the support units shown in  FIG. 4 ; 
           [0054]      FIGS. 12( a ) through 12( d )  are perspective, side, top, and exploded perspective views, respectively, of one of the locking members shown in  FIG. 4 ; 
           [0055]      FIGS. 13( a ) through 13( d )  are rear perspective, enlarged fragmentary rear perspective, enlarged fragmentary top, and enlarged fragmentary rear views, respectively, of one example of a tractor attachment that may be assembled using the kit of  FIG. 4 ; 
           [0056]      FIG. 13( e )  is a section view taken along line  1 - 1  of  FIG. 13( d ) ; 
           [0057]      FIG. 13( f )  is a section view taken along line  2 - 2  of  FIG. 13( d ) ; 
           [0058]      FIGS. 14( a ) through 14( e )  are front perspective, rear perspective, right side, partly exploded right side, and front views, respectively, of the tractor attachment of  FIGS. 13( a ) through 13( f ) , with the locking members of the tractor attachment not being shown for the sake of simplicity; 
           [0059]      FIGS. 15( a ) through 15( d )  are front perspective, rear perspective, front, and top views, respectively, of a second example of a tractor attachment that may be assembled using the kit of  FIG. 4 , with the locking members of the tractor attachment not being shown for the sake of simplicity; 
           [0060]      FIGS. 16( a ) through 16( d )  are front perspective, rear perspective, front, and top views, respectively, of a third example of a tractor attachment that may be assembled using the kit of  FIG. 4 , with the locking members of the tractor attachment not being shown for the sake of simplicity; 
           [0061]      FIGS. 17( a ) through 17( d )  are front perspective, rear perspective, front, and top views, respectively, of a fourth example of a tractor attachment that may be assembled using the kit of  FIG. 4 , with the locking members of the tractor attachment not being shown for the sake of simplicity; 
           [0062]      FIGS. 18( a ) through 18( d )  are front, front perspective, rear perspective, and right side views, respectively, of the tractor attachment of  FIGS. 13( a ) through 13( f )  being used to hold a log so that the log may be cut into smaller pieces using a chainsaw or the like, the locking members of the tractor attachment not being shown for the sake of simplicity; 
           [0063]      FIGS. 19( a ) through 19( c )  are front, front perspective, and rear perspective views, respectively, of the tractor attachment of  FIGS. 13( a ) through 13( f ) , the tractor attachment being shown with its support units positioned flush against its clamping unit, the locking members of the tractor attachment not being shown for the sake of simplicity; 
           [0064]      FIGS. 20( a ) through 20( c )  are front perspective, rear perspective, and right side views, respectively, of a forklift attachment that may be constructed according to the teachings of the present invention; 
           [0065]      FIGS. 21( a ) through 21( d )  are front perspective, rear perspective, partly exploded front perspective, and right side views, respectively, of a snow plow adapter attachment that may be constructed according to the present invention; 
           [0066]      FIGS. 22( a ) through 22( d )  are front perspective, rear perspective, partly exploded front perspective, and right side views, respectively, of a ball mount adapter attachment that may be constructed according to the present invention; 
           [0067]      FIGS. 23( a ) through 23( f )  are front perspective, rear perspective, front, top, right side, and exploded perspective views, respectively, of a first alternative mounting assembly to the mounting assembly shown in  FIGS. 4, 5 ( a ),  5 ( b ),  5 ( c ),  5 ( d ),  5 ( e ),  5 ( f ) and  5 ( g ); and 
           [0068]      FIGS. 24( a ) through 24( c )  are front perspective, rear perspective, and exploded perspective views, respectively, of a second alternative mounting assembly to the mounting assembly shown in  FIGS. 4, 5 ( a ),  5 ( b ),  5 ( c ),  5 ( d ),  5 ( e ),  5 ( f ) and  5 ( g ). 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0069]    Referring now to  FIG. 4 , there is shown a perspective view of a first embodiment of a grapple assembly kit constructed according to the present invention, the grapple assembly kit being represented generally by reference numeral  51 . 
         [0070]    Grapple assembly kit  51 , which may be used with a loader boom, such as, for example, loader boom  17 , may comprise a mounting assembly  53 , a plurality of clamping units  55 - 1  through  55 - 3 , a plurality of support units  57 - 1  through  57 - 2 , and a plurality of locking members  59 - 1  through  59 - 6 . As will be discussed below in greater detail, clamping units  55 - 1  through  55 - 3 , support units  57 - 1  and  57 - 2 , and locking member  59 - 1  through  59 - 6  are preferably modular in construction. As a result, a great number of different combinations of clamping units  55  and/or support units  57  and/or locking members  59  may be mounted on mounting assembly  53 , all such combinations coming within the scope of the present invention. In addition, it is to be understood that, although grapple assembly kit  51  is shown in the present embodiment as having three clamping units  55 - 1  through  55 - 3 , two support units  55 - 1  and  55 - 2 , and six locking members  59 - 1  through  59 - 6 , grapple assembly kit  51  may be modified so that the number of clamping units  55 - 1  through  55 - 3  may be greater than or less than three and/or so that the number of support units  55 - 1  and  55 - 2  may be greater than or less than two and/or so that the number of locking members  59 - 1  through  59 - 6  may be greater than or less than six. Additionally, although grapple assembly kit  51  is shown in the present application as being capable of mounting as few as a single clamping unit  55  (or a single support unit  57 ) on mounting assembly  53  or as many as up to three clamping units  55  and/or support units  57  on mounting assembly  53 , it is to be understood that the dimensions of mounting assembly  53 , clamping units  55 , and/or support units  57  may be modified to accommodate more than a total of three clamping units  55  and/or support units  57 . 
         [0071]    Mounting assembly  53 , which is also shown separately in  FIGS. 5( a ) through 5( g ) , may comprise a pair of mounting rails  61 - 1  and  61 - 2  and a pair of mounting brackets  63 - 1  and  63 - 2 . Mounting rails  61 - 1  and  61 - 2  and mounting brackets  63 - 1  and  63 - 2  may collectively form a generally rectangular frame. Rails  61 - 1  and  61 - 2 , which are preferably made of a high strength steel or other similarly suitable material, may be arranged generally parallel to one another. Rail  61 - 1  may be shaped to include a rear portion  65  and a front portion  67 . Rear portion  65  and front portion  67  of rail  61 - 1  may be separately fabricated and then fixedly joined to one another by suitable means, such as by welding; alternatively, rear portion  65  and front portion  67  of rail  61 - 1  may be fabricated as a unitary structure. As will be discussed further below, rear portion  65  of rail  61 - 1  may be fixed by welding or other suitable means to each of mounting brackets  63 - 1  and  63 - 2 . Front portion  65  of rail  61 - 1  may be shaped to include a plurality of notches  69  spaced along a top surface  71  thereof. 
         [0072]    Rail  61 - 2  may be shaped to include a rear portion  73  and a front portion  75 . Rear portion  73  and front portion  75  of rail  61 - 2  may be separately fabricated and then fixedly joined to one another by suitable means, such as by welding; alternatively, rear portion  73  and front portion  75  of rail  61 - 2  may be fabricated as a unitary structure. As will be discussed further below, rear portion  73  of rail  61 - 2  may be fixed by welding or other suitable means to each of mounting brackets  63 - 1  and  63 - 2 . Front portion  75  of rail  61 - 2  may be shaped to include a notch  77  disposed along a bottom surface  79  thereof. 
         [0073]    Brackets  63 - 1  and  63 - 2 , which are preferably made of a high strength steel or other similarly suitable material, may be arranged generally parallel to one another and generally perpendicularly relative to each of rails  61 - 1  and  61 - 2 . Bracket  63 - 1  may be shaped to include a rear portion  81  and a pair of side portions  83 - 1  and  83 - 2 . In a similar fashion, bracket  63 - 2  may be shaped to include a rear portion  85  and a pair of side portions  87 - 1  and  87 - 2 . Each of brackets  63 - 1  and  63 - 2  may be fabricated by separately forming the respective rear and side portions thereof and then by joining the rear and side portions together by suitable means, such as by welding. Alternatively, the respective rear and side portions of each of brackets  63 - 1  and  63 - 2  may be fabricated as a unitary structure. A first hook  91  may be fixed to the rear surface of rear portion  81  of bracket  63 - 1 , and a second hook  93  may be fixed to the rear surface of rear portion  85  of bracket  63 - 2 . Hooks  91  and  93  may be appropriately shaped to matingly fit over the top ends of the mounts of a suitably constructed loader boom (such as, for example, mounts  21 - 1  and  21 - 2 , respectively, of loader boom  17 , mounts  21 - 1  and  21 - 2  being seen best in  FIG. 3( a ) ) for use in mechanically coupling brackets  63 - 1  and  63 - 2  to the mounts of the loader boom. It is to be understood that, although hooks  91  and  93  are shown in the present embodiment as being separately constructed from rear portions  81  and  85 , respectively, hooks  91  and  93  may be integrally formed with rear portions  81  and  85 , respectively. A first pin  97  may be provided on rear portion  81  of bracket  63 - 1  and may project rearwardly therefrom, and a second pin  99  may be provided on rear portion  85  of bracket  63 - 2  and may project rearwardly therefrom. Pins  97  and  99  may be appropriately dimensioned for insertion through the pin holes in the mounts of a suitably constructed loader boom (such as, for example, pin holes  27 - 1  and  27 - 2 , respectively, of loader boom  17 , pin holes  27 - 1  and  27 - 2  being seen best in  FIG. 3( a ) ) for use in mechanically coupling brackets  63 - 1  and  63 - 2  to the mounts of the loader boom. Pin  97  may be shaped to include a transverse through hole  101 , and pin  99  may be similarly shaped to include a transverse through hole  103 . Each of through holes  101  and  103  may be used to receive a cotter pin (not shown) or the like for retaining pins  97  and  99  in the mounts of the loader boom. Pins  97  and  99  may be integrally formed with rear portions  81  and  85 , respectively, or, as shown in the present embodiment, pins  97  and  99  may be fabricated separately from rear portions  81  and  85 , respectively, and then may be joined thereto by suitable means, such as by welding. 
         [0074]    Each of side portions  83 - 1  and  83 - 2  of bracket  63 - 1  and each of side portions  87 - 1  and  87 - 2  of bracket  63 - 2  may be fixedly mounted on each of mounting rails  61 - 1  and  61 - 2 . In this manner, when mounting assembly  53  is mounted on the loader boom of a tractor, rails  61 - 1  and  61 - 2  may be disposed generally horizontally relative to the ground, and brackets  83 - 1  and  83 - 2  may be disposed generally perpendicularly relative to the ground. 
         [0075]    One or more voids  110  of various shapes and sizes may be provided in brackets  63 - 1  and  63 - 2  to reduce the weight thereof. 
         [0076]    As will become apparent from the description to follow, mounting assembly  53  is preferably provided in a fully assembled state, as is shown in  FIGS. 4 and 5 ( a ) through  5 ( f ), and is not intended to be disassembled thereafter into its component parts. Mounting assembly  53  may, however, be removably mounted on the loader boom of a tractor. The mounting of mounting assembly  53  on the loader boom of a tractor may be accomplished by matingly positioning hooks  91  and  93  over and around the respective top ends of the mounts of the loader boom (such as, for example, mounts  21 - 1  and  21 - 2  of loader boom  17 , mounts  21 - 1  and  21 - 2  being seen best in  FIG. 3( a ) ) and then by inserting pins  97  and  99  through the pin holes of the loader boom (such as, for example, pin holes  27 - 1  and  27 - 2  of loader boom  17 , pin holes  27 - 1  and  27 - 2  being seen best in  FIG. 3( a ) ). Cotter pins or the like then may be used to retain pins  97  and  99  in place in the mounts. To remove mounting assembly  53  from the loader boom, one may reverse the sequence of steps described above. 
         [0077]    Referring back now to  FIG. 4 , clamping units  55 - 1  through  55 - 3  may be identical in size, shape and construction to one another. Therefore, it is to be understood that the discussion below of the construction of clamping unit  55 - 1  may be equally applicable to clamping units  55 - 2  and  55 - 3 . 
         [0078]    Clamping unit  55 - 1 , which is also shown separately in  FIGS. 6( a ), 6( b ), 6( c ), 7( a ) and 7( b ) , may comprise a lower jaw  121 , an upper jaw  123 , a pair of pivot assemblies  125 - 1  and  125 - 2 , and a hydraulic cylinder assembly  127 . (It should be understood that hydraulic cylinder assembly  127  could be replaced with other mechanisms for moving upper jaw  123  relative to lower jaw  121 , such mechanisms including, but not being limited to, conventional mechanical, electrical, and electromechanical mechanisms, etc.) 
         [0079]    Lower jaw  121 , which is also shown separately in  FIGS. 8( a ) and 8( b ) , may comprise a pair of side members  131 - 1  and  131 - 2 . Side members  131 - 1  and  131 - 2 , which may be substantially identical to one another, may be generally L-shaped structures, each of which may include a generally horizontal portion  133  and a generally vertical portion  135 . Generally horizontal portion  133  may be shaped to include a plurality of jagged gripping elements  137  at its free end. Generally vertical portion  135  may be shaped to include along its rear an upper hook  139  and a lower hook  141 . Upper hook  139  may be sized and shaped to permit its mounting around the top of front portion  67  of rail  61 - 1 . Lower hook  141  may be sized and shaped to permit its mounting around the bottom of front portion  75  of rail  61 - 2 . Generally vertical portion  135  may also be shaped to include an upper hole  145  and a lower hole  147 . As will be discussed further below, holes  145  and  147  may be alternatively used to receive pivot assemblies  125 . Generally vertical portion  135  may additionally be shaped to include a T-shaped opening  149 , the purpose of which will become apparent below. 
         [0080]    Lower jaw  121  may additionally comprise a plurality of members that may be used to join together side members  131 - 1  and  131 - 2 . Such joining members may include a pair of tubes  151  and  153 , a plate  155 , and a plate  157 . Tube  151  may have a first end  151 - 1  inserted into an opening  161  of side member  131 - 1  and fixed therewithin, for example, by welding, and a second end  151 - 2  inserted into an opening  163  of side member  131 - 2  and fixed therewithin, for example, by welding. In a similar fashion, tube  153  may have a first end  153 - 1  inserted into an opening  165  of side member  131 - 1  and fixed therewithin, for example, by welding, and a second end  153 - 2  inserted into an opening  167  of side member  131 - 2  and fixed therewithin, for example, by welding. Plate  155  may have a first end  155 - 1  inserted into the vertical portion of T-shaped opening  149  of side member  131 - 1  and fixed therewithin, for example, by welding, and a second end  155 - 2  inserted into the vertical portion of T-shaped opening  149  of side member  131 - 2  and fixed therewithin, for example, by welding. In addition, plate  155  may be shaped to include a plurality of transverse openings  171 , one or more of which may be used to receive an end of a locking member  59  for use in securing clamping unit  55 - 1  to mounting assembly  53 . Plate  157  may have a first end  157 - 1  inserted into the horizontal portion of T-shaped opening  149  of side member  131 - 1  and fixed therewithin, for example, by welding, and a second end  157 - 2  inserted into the horizontal portion of T-shaped opening  149  of side member  131 - 2  and fixed therewithin, for example, by welding. In addition, plate  157  may be shaped to include a pair of slots  173  and  175 . Slot  173  may be used to receive a mounting member  177 , which may be fixed to plate  157 , for example, by welding, and slot  175  may be used to receive a mounting member  179 , which may be fixed to plate  157 , for example, by welding. Mounting members  177  and  179  may be used in mounting the fixed end of a hydraulic cylinder. 
         [0081]    Lower jaw  121  may further comprise a plurality of support members that may be used to support and/or strengthen lower jaw  121 . Such support members may include a plate  181  and a plurality of gussets  183 - 1  through  183 - 8 . Plate  181  may be inserted around tubes  151  and  153  and fixed thereto, for example, by welding. Gusset  183 - 1  may be inserted into an opening  185  in side member  131 - 1  and may be fixed to side member  131 - 1  and to tube  151  by welding or other suitable means. Gussets  183 - 2  and  183 - 3  may be inserted into openings  187  and  189 , respectively, in side member  131 - 1  and may be fixed to side member  131 - 1  and to tube  153  by welding or other suitable means. Gusset  183 - 4  may be inserted into an opening  191  in side member  131 - 2  and may be fixed to side member  131 - 2  and to tube  151  by welding or other suitable means. Gussets  183 - 5  and  183 - 6  may be inserted into openings  193  and  195 , respectively, in side member  131 - 2  and may be fixed to side member  131 - 2  and to tube  153  by welding or other suitable means. Gusset  183 - 7  may be fixed to plates  155 ,  157 , and  177  by welding or other suitable means, and gusset  183 - 8  may be fixed to plates  155 ,  157 , and  179  by welding or other suitable means. 
         [0082]    The components making up lower jaw  121  may be made of a high strength steel or other similarly suitable material. Voids  189  of various shapes and sizes may be provided in one or more of the components of lower jaw  121  to lessen the overall weight of lower jaw  121 . 
         [0083]    Upper jaw  123 , which is also shown separately in  FIGS. 9( a ) and 9( b ) , may comprise a pair of side members  201 - 1  and  201 - 2 . Side members  201 - 1  and  201 - 2 , which may be substantially identical to one another, may be generally L-shaped structures, each of which may include a first portion  203  and a second portion  205 . First portion  203  may be shaped to include a plurality of jagged gripping elements  207  on its bottom surface. In addition, first portion  203  may be shaped to include a hole  209 , which may be used to receive pivot assemblies  125 . First portion  205  may be shaped to include a plurality of jagged gripping elements  211  on its rear surface. 
         [0084]    Upper jaw  123  may additionally comprise a plurality of members that may be used to join together side members  201 - 1  and  201 - 2 . Such joining members may include a plate  215  and a plate  217 . Plate  215  may have a first end  219 - 1  inserted into an opening  221  of side member  201 - 1  and fixed therewithin, for example, by welding, and a second end  219 - 2  inserted into an opening  223  of side member  201 - 2  and fixed therewithin, for example, by welding. The bottom surface of plate  215  may be shaped to include a plurality of jagged gripping elements  227 . Plate  217  may be shaped to include a plurality of tabs  231 - 1  through  231 - 3  provided along one side thereof and a plurality of tabs  233 - 1  through  233 - 3  provided along an opposite side thereof. Tabs  231 - 1  through  231 - 3  may be inserted into openings  235 - 1  through  235 - 3 , respectively, of first portion  203  of side member  201 - 1  and may be fixed thereto by welding or other suitable means, and tabs  233 - 1  through  233 - 3  may be inserted into openings  237 - 1  through  237 - 3 , respectively, of first portion  203  of side member  201 - 2  and may be fixed thereto by welding or other suitable means. 
         [0085]    Upper jaw  123  may further comprise a pair of mounting members  241 - 1  and  241 - 2 , which may be used in the mounting of the movable end of a hydraulic cylinder. Mounting member  241 - 1  may be shaped to include a first tab  243  and a second tab  245 . First tab  243  and second tab  245  may be inserted into openings  247  and  249 , respectively, of plate  217  and may be fixed thereto by welding or other suitable means. Mounting member  241 - 2  may be shaped to include a first tab  251  and a second tab (not shown). First tab  251  and the second tab of mounting member  241 - 2  may be inserted into openings  255  and  257 , respectively, of plate  217  and may be fixed thereto by welding or other suitable means. 
         [0086]    The components making up upper jaw  123  may be made of a high strength steel or other similarly suitable material. Voids  259  of various shapes and sizes may be provided in one or more of the components of upper jaw  123  to lessen the overall weight of upper jaw  123 . For reasons to become apparent below, upper jaw  123  may be dimensioned relative to lower jaw  121  so that holes  209  of upper jaw  123  may be positioned just interior to holes  145  or  147  of lower jaw  121 . 
         [0087]    Pivot assemblies  125 - 1  and  125 - 2  (seen best in  FIG. 6( c ) ), which may be used to pivotally mount upper jaw  123  on lower jaw  121 , may be identical to one another, and each may include a threaded bolt  261 , a first washer  263 , a sleeve  265 , a second washer  267 , and a nut  269 . Bolt  261  may be appropriately dimensioned to pass through either hole  145  or hole  147  of lower jaw  121  and through hole  209  of upper jaw  123 , with the head  271  of bolt  261  being positioned on the interior side of upper jaw  123 . First washer  263  may also be positioned on the interior side of upper jaw  123 . Sleeve  265  may be positioned within hole  209  of upper jaw  123 , second washer  267  may be positioned between upper jaw  123  and lower jaw  121 , and nut  269  may be positioned on the exterior side of lower jaw  121 . 
         [0088]    By inserting bolts  261  of pivot assemblies  125 - 1  and  125 - 2  through either upper hole  145  of lower jaw  121  (see, for example,  FIGS. 6( b ) and 7( a ) ) or through lower hole  147  of lower jaw  121  (see, for example,  FIGS. 10( a ) and 10( b ) ), one can adjust the speed with which upper jaw  123  closes on lower jaw  121  and the clamping force between jaws  121  and  123 . More specifically, when bolt  261  is inserted through upper hole  145 , the closing speed of upper jaw  123  is faster than the closing speed of upper jaw  123  when bolt  261  is inserted through lower hole  147 . On the other hand, when bolt  261  is inserted through lower hole  147 , the clamping force between jaws  121  and  123  is greater than the clamping force that is produced when bolt  261  is inserted through upper hole  145 . For example, when the spacing between the respective centers of upper hole  145  and hole  209  is approximately 2.69 inches, when the spacing between the respective centers of lower hole  147  and hole  209  is approximately 4.30 inches, and when using a hydraulic cylinder with a 4240 lb cylinder force at 2400 psi, the increase in clamping force using lower hole  147 , instead of upper hole  145 , may be greater by, for example, approximately 114% when upper jaw  123  is at its most open position, may be greater by, for example, approximately 45% when upper jaw  123  is at its midpoint, and may be greater by, for example, approximately 72% when upper jaw  123  is in its closed position. 
         [0089]    As seen best in  FIG. 6( c ) , hydraulic cylinder assembly  127  may comprise a hydraulic cylinder  281  and hardware for mounting hydraulic cylinder  281  to jaws  121  and  123 . Hydraulic cylinder  281 , the operation of which may be controlled by conventional means (not shown), may comprise a fixed portion  283  and a movable portion  285 . Fixed portion  283  may include a tubular member  287 . Tubular member  287  may be appropriately dimensioned to be coupled to mounting members  177  and  179  of lower jaw  121  using hardware that may include a threaded bolt  291 , a plurality of washers  293 , and a nut  295 . Movable portion  285  of hydraulic cylinder  281  may include a tubular member  297 . Tubular member  297  may be appropriately dimensioned to be coupled to mounting members  241 - 1  and  241 - 2  of upper jaw  123  using hardware that may include a threaded bolt  299 , a plurality of washers  301 , and a nut  303 . 
         [0090]    Referring now to  FIGS. 10( c ) and 10( d ) , there are shown fragmentary right perspective and fragmentary left perspective views, respectively, of an alternative type of clamping unit to the type of clamping unit shown in  FIGS. 6( a ) through 6( c ) , the alternative type of clamping unit being represented generally by reference numeral  56 . (Clamping unit  56  is shown in the present embodiment equipped with hydraulic hoses  58 - 1  and  58 - 2  used in the operation of hydraulic cylinder  281 .) 
         [0091]    Clamping unit  56  may be similar in most respects to clamping units  55 - 1  through  55 - 3 , the principal difference between the two types of clamping units being that clamping unit  56  may further comprise a pair of fangs  60 - 1  and  60 - 2 , which may be provided to endow clamping unit  56  with an enhanced gripping power. Fang  60 - 1  may be securely mounted to side member  201 - 1  of upper jaw  123 , and fang  60 - 2  may be securely mounted to side member  201 - 2  of upper jaw  123 . Fangs  60 - 1  and  60 - 2  may be secured to upper jaw  123  using suitable hardware. For example, in the present embodiment, a washer (not shown) may be inserted over each of a pair of bolts  62 , and bolts  62  may then be inserted through openings in fang  60 - 1  and then through an opening in side member  201 - 1 . An additional washer (not shown) may then be inserted over each of bolts  62  from the inside of side member  201 - 1 , and a nut  64  may then be secured to each of bolts  62 . Fang  60 - 2  may be secured to side member  201 - 2  in a corresponding manner. If desired, fangs  60 - 1  and  60 - 2  may be removably mounted on upper jaw  123  to permit their attachment and removal when desired. In another embodiment (not shown), fangs  60 - 1  and  60 - 2  may be replaced with a single fang that is centrally disposed on upper jaw  123 . 
         [0092]    As can be appreciated, any one or more of clamping units  55 - 1  through  55 - 3  may be replaced with a corresponding number of clamping units  56 . Alternatively, clamping units  55 - 1  through  55 - 3  may be reversibly converted to clamping unit  56  and vice versa by the attachment and removal of fangs  60 - 1  and  60 - 2 . 
         [0093]    Referring back now to  FIG. 4 , support units  57 - 1  and  57 - 2  may be identical in size, shape and construction to one another. Therefore, it is to be understood that the discussion below of the construction of support unit  57 - 1  may be equally applicable to support unit  57 - 2 . 
         [0094]    Support unit  57 - 1 , which is also shown separately in  FIGS. 11( a ) and 11( b ) , may be similar in size, shape and construction to lower jaw  121  of clamping unit  55 - 1 , some of the more significant differences between the two structures being that support unit  57 - 1  may not include the following structures of lower jaw  121 : plate  157 , mounting members  177  and  179 , and gussets  183 - 7  and  183 - 8 . In addition, whereas side members  131 - 1  and  131 - 2  of lower jaw  121  may include a T-shaped opening  149 , support unit  57 - 1  may include side members  321 - 1  and  321 - 2  that may include a rectangular opening  323 . Additionally, side members  321 - 1  and  321 - 2  of support unit  57 - 1  may differ from lower jaw  121  of clamping unit  55 - 1  in that, instead of having an upper hole  145  and a lower hole  147 , each of side members  321 - 1  and  321 - 2  may have an upper hole  325  and a lower hole  327 . Upper hole  325  and lower hole  327  may be centered in analogous locations to upper hole  145  and lower hole  147 , respectively, but may have an increased diameter, as compared to upper hole  145  and lower hole  147 , so that each of holes  325  and  327  is large enough to receive nut  269  of pivot assembly  125  of a neighboring clamping unit, thereby enabling the side members of neighboring support and clamping units to be brought into close proximity or contact with one another. Finally, support unit  57 - 1  may differ from lower jaw  121  of clamping unit  55 - 1  in that support unit  57 - 1  may include a plate  331 , instead of plate  155 . Plate  331  may be shaped to include a plurality of transverse openings  333 , one or more of which may be used to receive an end of a locking member  59  for use in securing support unit  57 - 1  to mounting assembly  53 . 
         [0095]    Like lower jaw  121  of clamping unit  55 - 1 , support unit  57 - 1  may be made of a high strength steel or similarly suitable material. 
         [0096]    Referring back now to  FIG. 4 , locking members  59 - 1  through  59 - 6  may be identical in size, shape and construction to one another. Therefore, it is to be understood that the discussion below of the construction of locking member  59 - 1  may be equally applicable to each of locking members  59 - 2  through  59 - 6 . 
         [0097]    Locking member  59 - 1 , which is also shown separately in  FIGS. 12( a ) through 12( d ) , may comprise a first member  351  and a second member  353 . First member  351 , which may be made of a high strength steel or other similarly suitable material, may be generally rectangular in shape and may comprise a front portion  355 , an intermediate portion  357 , and a rear portion  359 . As will be discussed further below, first member  351  may be appropriately dimensioned so that intermediate portion  357  may be received within a notch  69  of mounting assembly  53 , with front portion  355  extending forwardly so that it may extend either through a transverse opening  171  in a clamping unit  55  or through a transverse opening  333  in a support unit  57  and with rear portion  359  extending rearwardly from notch  69 . Rear portion  359  may have a width w 1  that may be less than the width w 2  of intermediate portion  357 , and front portion  355  may have a width w 3  that may be intermediate to that of intermediate portion  357  and rear portion  359 . (Alternatively, in another embodiment (not shown), the width w 3  of front portion  355  may be the same as or greater than the width w 2  of intermediate portion  357 .) Rear portion  359  may have a length l 1  that may permit locking member  59 - 1  to be grasped and manipulated via rear portion  359 . 
         [0098]    Second member  353 , which may also be made of a high strength steel or similarly suitable material, may be generally rectangular in profile and may comprise a first end  361  and a second end  363 . First end  361  of second member  353  may be received within an opening  365  in first member  351 , and, with first end  361  thus received within opening  365 , second member  353  may be fixed to first member  351  by welding or other suitable means. First member  351  and second member  353  may be oriented generally perpendicularly to one another, and second member  353  may be positioned along the length of first member  351  so that, when intermediate portion  357  of first member  351  is positioned within a notch  69  of mounting assembly  53 , second member  353  may be positioned between mounting assembly  53  and whichever of clamping unit  55  or support unit  57  is secured to mounting assembly  53 . 
         [0099]    It is to be understood that, although locking member  59 - 1  is shown in the present embodiment as being made from two separate pieces that are joined to one another, namely, first member  351  and second member  353 , locking member  59 - 1  could be fabricated as a unitary structure. 
         [0100]    A void  371  may be provided in locking member  59 - 1  for use in fastening to the attachment. 
         [0101]    Referring now to  FIGS. 13( a ) through 13( f ) , there are shown various views of one example of a tractor attachment constructed using grapple assembly kit  51 , the exemplary tractor attachment illustrating how a locking member  59  may be used in securing a clamping unit  55  or a support unit  57  to mounting assembly  53 . 
         [0102]    The tractor attachment shown in  FIGS. 13( a ) through 13( f )  is represented generally by reference numeral  401  and may comprise mounting assembly  53 , a single clamping unit (the clamping unit being represented in the present embodiment by clamping unit  55 - 1 ), and a pair of support units, one on each side of the clamping unit (the support units being represented in the present embodiment by support units  57 - 1  and  57 - 2 ). Clamping unit  55 - 1  may be mounted on mounting assembly  53  by positioning hooks  139  of clamping unit  55 - 1  around the top of front portion  67  of rail  61 - 1  of mounting assembly  53  and by positioning hooks  141  of clamping unit  55 - 1  around the bottom of front portion  75  of rail  61 - 2  of mounting assembly  53 . In like fashion, each of support units  57 - 1  and  57 - 2  may be mounted on mounting assembly  53  by positioning hooks  139  of support units  57 - 1  and  57 - 2  around the top of front portion  67  of rail  61 - 1  of mounting assembly  53  and by positioning hooks  141  of support units  57 - 1  and  57 - 2  around the bottom of front portion  75  of rail  61 - 2  of mounting assembly  53 . Then, to secure the thus-mounted clamping unit  55 - 1  or support units  57 - 1  and  57 - 2  to mounting assembly  53 , one or more locking members  59  may be used in the manner hereinafter described. More specifically, each mounting member  59  may be held by its rear portion  359  in the hand of a user and may be oriented so that its second member  353  is directed generally upwardly. Then, front portion  355  of mounting member  59  may be manually inserted first through a notch  69  in front portion  67  of rail  61 - 1  and then, depending on the type of unit being secured to mounting assembly  53 , either through a transverse opening  171  in a clamping unit  55  that is aligned with the notch  69  or through a transverse opening  333  in a support unit  57  that is aligned with the notch  69 . Such insertion of front portion  355  may proceed until further insertion is not possible. Rear portion  359  may then be manually rotated approximately 180 degrees until second member  353  extends downwardly between rail  61 - 1  and the clamping unit or support unit. With locking member  59  thus positioned, the clamping unit  55  or support unit  57  cannot be removed from mounting assembly. The above-described process is illustrated, at least in part, by  FIGS. 13( a ) through 13( f ) , in which locking member  59 - 1  is shown in its fully installed state to secure support unit  57 - 1  to rail  61 - 1 , locking member  59 - 2  is shown in the process of being rotated after having been inserted through notch  69  and opening  333 , and locking member  59 - 3  is shown in its fully installed state to secure clamping unit  55 - 1  to rail  61 - 1 . 
         [0103]    As can be appreciated, to remove a thus-locked clamping unit  55  or support unit  57 , one may simply rotate locking member  59  approximately 180 degrees and then withdraw locking member  59  from the clamping unit  55  or support unit  57  and then from notch  69 . With locking member  59  thus removed, a clamping unit  55  or a support unit  57  that had previously been mounted on mounting assembly  53  may thereafter be removed therefrom, thereby facilitating the transport and/or storage of the components of kit  51 . 
         [0104]    It is to be understood that the number of locking members  59  used per clamping unit  55  or support unit  57  may vary. For example, in the present embodiment, two locking members  59 - 1  and  59 - 2  are shown being used with support unit  57 - 1 , and one locking member  59 - 3  is shown being used with clamping unit  55 - 1 . (Also, although no locking members  59  are shown being used with support unit  57 - 2 , the use of at least one such locking member  59  is preferred.) In general, it is preferred that at least two locking members  59  be used per clamping unit  55  or support unit  57 . In addition, it is to be understood that the selection of which notch  69  or which opening  171  or  333  may be used for use with a locking member  59  may vary. 
         [0105]    Because of the modular nature of clamping units  55  and support unit  57 , various combinations of clamping units  55  and support units  57  may be mounted on mounting assembly  53  to create a variety of different grapple-type tractor attachments. For example,  FIGS. 14( a ) through 14( e )  are various additional views of tractor attachment  401 , with locking members  59  not being shown for the sake of simplicity. By contrast,  FIGS. 15( a ) through 15( d )  are various views of a second example of a grapple-type tractor attachment that may be constructed using kit  51 , the grapple-type tractor attachment of  FIGS. 15( a ) through 15( d )  being represented generally by reference numeral  501 . Tractor attachment  501  may differ principally from tractor attachment  401  in that tractor attachment  501  may not include support units  57 - 1  and  57 - 2 . (Due to the presence of support units  57 - 1  and  57 - 2  in tractor attachment  401 , tractor attachment  401  may possess increased support for more load capacity than may be the case with tractor attachment  501 .)  FIGS. 16( a ) through 16( d )  are various views of a third example of a grapple-type tractor attachment that may be constructed using kit  51 , the grapple-type tractor attachment of  FIGS. 16( a ) through 16( d )  being represented generally by reference numeral  601 . Tractor attachment  601  may differ from tractor attachment  401  in that grapple unit  55 - 1  of tractor attachment  401  may be replaced with support unit  57 - 1  in tractor attachment  601  and in that support units  57 - 1  and  57 - 2  of tractor attachment  401  may be replaced with grapple units  55 - 1  and  55 - 2 , respectively, in tractor attachment  601 . As compared to tractor attachments  401  and  501 , tractor attachment  601  may provide greater clamping power, and, as compared to tractor attachment  501 , tractor attachment  601  may provide a wider holding area.  FIGS. 17( a ) through 17( d )  are various views of a fourth example of a grapple-type tractor attachment that may be constructed using kit  51 , the grapple-type tractor attachment of  FIGS. 17( a ) through 17( d )  being represented generally by reference numeral  701 . Tractor attachment  701  may differ from tractor attachment  401  in that support units  57 - 1  and  57 - 2  of attachment  401  may be replaced with clamping units  55 - 2  and  55 - 3 , respectively. As compared to tractor attachments  401 ,  501 , and  601 , tractor attachment  701  may provide greater clamping power, and, as compared to tractor attachment  501 , tractor attachment  701  may provide a wider holding area. 
         [0106]    It is to be understood that other combinations of the components of kit  51  are possible and that all such combinations come within the scope of the present invention. 
         [0107]    Referring now to  FIGS. 18( a ) through 18( d ) , there are shown various views of one possible use to which tractor attachment  401  may be put, namely, to hold a wooden log L securely in such a manner as to permit the log L to be cut into smaller pieces using, for example, a chainsaw of the like. As can be seen best in  FIG. 18( a ) , tractor attachment  401  may have an overall length l 2  that may be, for example, approximately 48 inches, and clamping unit  55 - 1  may be spaced apart from each of support units  57 - 1  and  57 - 2  by a distance d 1  that may be, for example, approximately 3 inches. Consequently, by cutting the log L at opposite ends of tractor attachment  401 , for example, along imaginary lines  751  and  753  shown in  FIG. 18( a ) , one may obtain a log of approximately 48 inches, which may be a suitable length if the log is to be used as firewood for a typical outdoor wood boiler. Moreover, by additionally cutting the thus-cut log approximately midway between clamping unit  55 - 1  and support unit  57 - 1 , for example, along imaginary line  755  shown in  FIG. 18( a ) , and approximately midway between clamping unit  55 - 1  and support unit  57 - 2 , for example, along imaginary line  757  shown in  FIG. 18( a ) , one may obtain three logs of approximately 16 inches each, which may be a suitable length if the logs are to be used as firewood for a typical interior wood stove. 
         [0108]    As noted above, the spacing between neighboring clamping unit(s)  55  and/or support unit(s)  57  on mounting assembly  53  may be varied simply by positioning the neighboring clamping unit(s)  55  and/or support unit(s)  57  at desired locations along rails  61 - 1  and  61 - 2  and preferably then securing the clamping unit(s)  55  and/or support unit(s)  57  in place using locking members  59 . Referring now to  FIGS. 19( a ) through 19( c ) , tractor attachment  401  is shown with the side members of support units  57 - 1  and  57 - 2  positioned flush against the side members of clamping unit  55 - 1 . As noted above, the capability to position the side members of support units  57 - 1  and  57 - 2  flush against the side members of clamping unit  55 - 1  may be attributable, at least in part, to the fact that holes  325  and  327  of support units  57 - 1  and  57 - 2  may be appropriately dimensioned to permit the outside ends of pivot assemblies  125 - 1  and  125 - 2  to pass therethrough. If desired, bolts or other fasteners (not shown) may be used to couple support units  57 - 1  and  57 - 2  to clamping unit  55 - 1  to increase the rigidity of the structure. 
         [0109]    Kit  51  may further comprise additional components that may be used in conjunction with mounting assembly  53  to provide alternative tractor attachments that are not of a grapple variety. For example,  FIGS. 20( a ) through 20( c )  are various views of a forklift-type tractor attachment  801 . Attachment  801  may comprise a pair of forklift tines  803 - 1  and  803 - 2  that may be removably mounted on mounting assembly  53 .  FIGS. 21( a ) through 21( d )  are various views of a snow plow adapter attachment  851 . Attachment  851  may comprise an adapter  853  that may be removably mounted on mounting assembly  53 .  FIGS. 22( a ) through 22( d )  are various views of a ball mount adapter attachment  901 . Attachment  901  may comprise an adapter  903  that may be removably mounted on mounting assembly  53 . Accordingly, kit  51  may include one or more of forklift tines  803 - 1  and  803 - 2 , adapter  853  and adapter  903 . 
         [0110]    The various tractor attachments described above are designed to be used in connection with a loader boom on which mounting assembly  53  can be mounted, an example of such a loader boom being loader boom  17 . However, as can readily be appreciated, one may replace mounting assembly  53  with an alternative mounting assembly to permit the tractor attachment to be attached to other types of loader booms. All such alternative mounting assemblies for use with alternative loader booms are intended to come within the scope of the present invention. 
         [0111]    For example, referring now to  FIGS. 23( a ) through 23( f ) , there are shown various views of one such alternative mounting assembly to mounting assembly  53 , the alternative mounting assembly being represented generally by reference number  953 . Mounting assembly  953 , which may be used with, for example, loader boom  35  (as seen in  FIG. 3( b ) ), may be similar in many respects to mounting assembly  953 . For example, mounting assembly  953 , like mounting assembly  53 , may comprise rails  61 - 1  and  61 - 2 . On the other hand, mounting assembly  953  may differ from mounting assembly  53  in that, whereas mounting assembly  53  may comprise mounting brackets  63 - 1  and  63 - 2 , mounting assembly  953  may instead comprise mounting brackets  955 - 1  and  955 - 2 . Brackets  955 - 1  and  955 - 2 , which are preferably made of a high strength steel or other similarly suitable material, may be arranged generally parallel to one another and generally perpendicularly relative to each of rails  61 - 1  and  61 - 2 . Bracket  955 - 1  may be shaped to include a support  957 - 1 , a plurality of tubular guides  959 - 1  through  959 - 4 , and a block  961 - 1 . In a similar fashion, bracket  955 - 2  may be shaped to include a support  957 - 2 , a plurality of tubular guides  959 - 5  through  959 - 8 , and a block  961 - 2 . Brackets  955 - 1  and  955 - 2  may be adapted to receive the front ends of loader boom  35  (loader boom  35  being shown in  FIG. 3( b ) ). Pin  39 - 1  of loader boom  35  may be inserted through guide  959 - 1  of mounting assembly  953 , through plates  41 - 1  and  41 - 2  of loader boom  35 , and through guide  959 - 2  of mounting assembly  953 . Pin  39 - 2  of loader boom  35  may be inserted through guide  959 - 5  of mounting assembly  953 , through plates  41 - 3  and  41 - 4  of loader boom  35 , and through guide  959 - 6  of mounting assembly  953 . Pin  39 - 3  of loader boom  35  may be inserted through guide  959 - 3  of mounting assembly  953 , through end  45 - 1  of loader boom  35 , and through guide  959 - 4  of mounting assembly  953 . Pin  39 - 4  of loader boom  35  may be inserted through guide  959 - 7  of mounting assembly  953 , through end  45 - 2  of loader boom  35 , and through guide  959 - 8  of mounting assembly  953 . Guides  959 - 1 ,  959 - 3 ,  959 - 5  and  959 - 7  may be provided with transverse openings  971 - 1  through  971 - 4 , respectively, for use in receiving fasteners  47 - 1 ,  47 - 3 ,  47 - 2 , and  47 - 4 , respectively, of loader boom  35 . 
         [0112]    For example, referring now to  FIGS. 24( a ) through 24( c ) , there are shown various views of a second alternative mounting assembly to mounting assembly  53 , the second alternative mounting assembly being represented generally by reference number  973 . Mounting assembly  973 , which may be used with, for example, another conventional loader boom (not shown), may be similar in many respects to mounting assemblies  53  and  953 . For example, mounting assembly  973 , like mounting assemblies  53  and  953 , may comprise a rail  61 - 1  comprising a rear portion  65  and a front portion  67  and a rail  61 - 2  comprising a rear portion  73  and a front portion  75 . On the other hand, mounting assembly  973  may differ from mounting assemblies  53  and  953  in that, whereas mounting assembly  53  may comprise mounting brackets  63 - 1  and  63 - 2  and whereas mounting assembly  953  may comprise mounting brackets  955 - 1  and  955 - 2 , mounting assembly  973  may comprise mounting brackets  975 - 1  and  975 - 2 . Brackets  975 - 1  and  975 - 2  are preferably made of a high strength steel or other similarly suitable material. Bracket  975 - 1  may comprise an outside side member  977 - 1 , an inside side member  977 - 2 , and a rear member  977 - 3 . Bracket  975 - 2 , which may be a mirror image of bracket  975 - 1 , may comprise an outside side member  979 - 1 , an inside side member  979 - 2 , and a rear member  979 - 3 . Brackets  975 - 1  and  975 - 2  are adapted to be mounted on the front ends of a corresponding loader boom (not shown). 
         [0113]    As can be appreciated, while the various different types of tractor attachments described above have been discussed in the context of a common kit, such as kit  51 , from which any of these tractor attachments may be derived, it is to be understood that such tractor attachments need not be derived from a kit capable of making more than one type of tractor attachment and, instead, could be made from a starter kit consisting of, for example, a mounting assembly  53  (or a mounting assembly  953 ) and a single clamping unit  55  or  56  (and, optionally, one or more locking members  59 ). As can be appreciated, the design of the present tractor attachment kit permits clamping unit  55  (or clamping unit  56 ) and support units  57  to be arranged in various different combinations and permits the tractor attachment to be assembled and disassembled easily to facilitate transport and storage. In addition, the design of the present tractor kit permits an owner to purchase, relatively inexpensively, a starter kit with a minimal number of components and to add components as budget allows. 
         [0114]    In view of the above, one of the desirable features of the present invention is its modular design. Existing grapples are built as one solid continuous unit that weighs several hundred pounds and consumes a large storage space. By contrast, as a result of the design of the present invention, the grapple-type tractor attachment of the present invention can be made as several components that can be stored, transported and used independently of one another. Additionally, because of the modular design of the present invention, these components of the attachment can be combined in different ways, depending on the needs of the user. Moreover, the spacing between neighboring units can be adjusted, if desired, so that, for example, neighboring clamping and support units are either substantially flush with one another or spaced apart by a short distance, such as a few inches. 
         [0115]    Another desirable feature of the present invention is that the clamping unit can be used in either of two different modes, a first mode having a greater clamping force but slower closing speed or a second mode having a lesser clamping force but faster closing speed. By contrast, existing grapples have only a single clamping force and closing speed. 
         [0116]    Yet another desirable feature of the present invention is the provision of one or more fangs on the upper jaw of the clamping unit, which one or more fangs may be removably mounted. 
         [0117]    Still another desirable feature of the present invention is the design of the locking member. 
         [0118]    A further desirable feature of the present invention is that the mounting assembly of the grapple-type tractor attachment can also be used with other types of attachment structures, such as forklift tines, a plow adapter, a trailer receiver, and the like, to provide other types of tractor attachment functionalities. 
         [0119]    The embodiments of the present invention described above are intended to be merely exemplary and those skilled in the art shall be able to make numerous variations and modifications to it without departing from the spirit of the present invention. All such variations and modifications are intended to be within the scope of the present invention.