Abstract:
A stand used for supporting spools of wire and the like includes a cam which is operable to increase the length of a leg to thereby raise the spool of wire off of the ground. The stand is adjustable to allow its use with different sizes of spools of wire. The stand allows a single person to raise a spool of wire weighing thousands of pounds off of the ground and support the same to allow the spool to rotate freely upon an axle.

Description:
RELATED APPLICATIONS 
     The present application claims the benefit of U.S. Provisional Application Ser. No. 60/971,518, filed Sep. 11, 2007, which is expressly incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. The Field of the Invention 
     The present invention relates to jacks and support stands. More specifically, the present invention relates to an improved jack and support stand for holding a spool of electrical wire or the like while working with the wire. 
     2. State of the Art 
     Installing electrical wires in commercial, industrial, or municipal applications typically involves wires of significantly greater length and diameter than in an ordinary home. The wires are typically installed by pulling the same through a previously installed electrical conduit. As such, these wires are typically available on large spools. Spools of wire for these types of applications are often three feet or larger in diameter, and may weigh more than a thousand pounds. 
     To facilitate installation of the wire, the spool of wire is mounted on a stand by placing an axle (such as a steel pipe) through the axis of the spool and placing the axle ends on the stand. The spool rotates about the axle as the wire is pulled from the spool into the conduit. Existing stands are undesirable as they require a person to exert a large amount of force to lift the spool off of the ground and onto the stand to thereby allow the spool to spin freely. Larger spools of wire may require multiple persons or even machinery to lift on to the stands. Available stands are also undesirable as there is some danger of the axle falling off of the top of existing stands due to the lateral forces which may be applied when installing the wire into a conduit. Thicker wires will often require a relatively high force to pull the wire from the spool, and this force may displace the spool from the stand. It will be appreciated that this creates a safety danger for persons working around the spool of wire, especially where the spool of wire is heavy and not easily moved by a single person. 
     There is thus a need for an improved stand for supporting spools of wire during installation. There is need for a stand which incorporates a lifting mechanism which allows a person to lift a spool of wire off of the ground with minimal effort. There is need for a stand which securely holds the axle while allowing the axle and spool of wire to turn freely while dispensing wire. There is also a need for a stand which is stable, minimizing the risk of accidents while in use. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide an improved stand for supporting spools of wire. 
     According to one aspect of the invention, a stand is provided which includes an integrated lifting mechanism. The lifting mechanism allows a person to lift a spool weighing 2000 pounds with a relatively small amount of effort. 
     According to another aspect of the invention, a stand is provided which captures and securely holds the axle used for supporting the spool of wire, eliminating the risk that the axle is pulled horizontally off of the stand during use. The stand may use a clamp that holds the axle, and may use bearings on the clamp to allow for easy rotation of the axle. 
     According to another aspect of the invention, a stand is provided which is adjustable to accommodate different sizes of spools. The stand may incorporate one or more adjustable support legs to alter the height of the stand, and may allow the position of the legs to be altered on a base member to maintain the stability and functionality of the stand. Thus, a person need only have a single pair of stands to use with a variety of different spool sizes. 
     According to another aspect of the invention, the stand may be collapsible to allow for convenient storage and transportation of the stand. 
     These and other aspects of the present invention are realized in a combination stand and jack for wire spools as shown and described in the following figures and related description. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Various embodiments of the present invention are shown and described in reference to the numbered drawings wherein: 
         FIG. 1  shows a perspective view of a combination stand and jack according to the present invention; 
         FIG. 2  shows a side view of the stand of  FIG. 1 ; 
         FIG. 3  shows a side view of the stand of  FIG. 1 ; 
         FIG. 4  shows a side view of the stand of  FIG. 1 ; 
         FIG. 5  shows a perspective view of the jaw of the stand of  FIG. 1 ; 
         FIG. 6  shows a perspective view of the stand of  FIG. 1 ; and 
         FIG. 7  shows a perspective view of a pair of the stands of  FIG. 1  in use. 
     
    
    
     It will be appreciated that the drawings are illustrative and not limiting of the scope of the invention which is defined by the appended claims. The embodiments shown accomplish various aspects and objects of the invention. It is appreciated that it is not possible to clearly show each element and aspect of the invention in a single figure, and as such, multiple figures are presented to separately illustrate the various details of the invention in greater clarity. Similarly, not every embodiment need accomplish all advantages of the present invention. 
     DETAILED DESCRIPTION 
     The invention and accompanying drawings will now be discussed in reference to the numerals provided therein so as to enable one skilled in the art to practice the present invention. The drawings and descriptions are exemplary of various aspects of the invention and are not intended to narrow the scope of the appended claims. 
     Turning now to  FIG. 1 , a perspective view of a stand  10  according to the present invention is shown. The stand  10  includes a base  14  which rests on the ground during use. A rear leg  18  is pivotably attached to the base  14  at pivot  22 . Pivot  22  may be formed with side plates  26  which are attached to the base  14  and which receive the rear leg  18  therebetween. 
     The rear leg  18  is telescopic, and includes an outer tube  30  and an inner tube  34 . A jack  38  is used to extend and retract the inner tube  34  relative to the outer tube  30 . Pivoting the lever  42  away from the outer tube  30  retracts the inner tube  34 , and lowering the lever  42  towards the outer tube  30  extends the inner tube  34 . According to a preferred embodiment, the jack  38  uses a cam action to extend or retract the inner tube  34 . The jack  38  is used to lift a spool of wire off of the ground once the stand is properly positioned. 
     The inner tube  34  is connected to a clamping jaw, generally indicated at  46 , which holds the axle used to support the spool of wire ( FIGS. 5-7 ). The jaw  46  includes a fixed base portion  50  that includes left and right halves  50   a ,  50   b  and a clamping portion  54  which also includes left and right halves  54   a ,  54   b . The clamping portion  54  is pivotably attached to the base portion  50  at pivot  58 . The jaw  46  is formed from two sides (designated a and b) to aid in holding the axle and to keep the axle perpendicular to the jaw  46 , helping to brace the stand  10  laterally when in use and preventing the stand from falling over. A plurality of bearings  62  are attached to the jaw  46  such that only the bearings  62  contact an axle when the axle is clamped in the jaw  46 . A presently preferred embodiment includes four bearings  62  attached to the base portion  50   a ,  50   b  (two bearing on either side of the base portion) and four bearings attached to the clamping portion  54  (two bearings on either side of the clamping portion). It will be appreciated that a different number of bearings  62 , such as 6 or 10, may also be used. 
     The clamping portion  54  is held in a closed position as shown by passing a pin  66  through holes  70  or  74  formed in the clamping portion and a corresponding hole  78  ( FIG. 2 ) formed in the base portion  50 . Two holes  70 ,  74  are formed in the clamping portion  54  so as to allow for two sizes of axles. Three holes may be formed in the clamping portion  54 , or another hole may be formed in the base portion  50  to accommodate additional sizes of axles. Hole  70  is positioned such that a 1.5 inch pipe is held in the jaw  46  and hole  74  is positioned such that a 2 inch pipe is held in the jaw. These two pipe sizes are commonly used as axles for spools of wire, and the jaw  46  is configured to quickly and easily accept these two sizes. Removal of the pin  66  allows the clamping portion  54  to swing away from the base portion  50  at the pivot  58  to receive an axle. The use of the pin  66  and holes  70 ,  74 ,  78  is advantageous as it allows the clamping jaw  46  to be quickly locked around the commonly used pipe axles without tools. 
     The stand  10  also includes a front leg  82 . The front leg  82  is telescopic, and includes an outer tube  86  and an inner tube  90 . The inner tube  90  includes a plurality of holes  94  and the outer tube  86  includes a corresponding hole  98  such that a pin  102  may be passed through hole  98  and a hole  94  to fix the length of the front leg  82 . The front leg  82  is pivotably attached to the base portion  50  of the jaw  46  at pivot  106 , and includes a post  110  which is placed in one of a plurality of holes  114  formed in the base  14 . The length of the front leg  82  may be adjusted along with the position at which the front leg is attached to the base  14  in order to accommodate spools of wire of varying sizes. 
       FIG. 2  shows a side view of the stand  10 . Several aspects of the stand are more easily visible. The pivot  106  is more easily seen. Also, the hole  78  on the base portion  50  of the jaw  46  is more easily seen. An axle  118  has been placed in the jaw  46 . It can be seen how the axle  118  rests on the bearings  62  which are attached to the base portion  50   
       FIG. 2  also illustrates the jack, generally indicated at  38 . The lever  42  has a semi circular cam  122  attached thereto and is attached to the inner tube  34  at pivot  126 . The curved cam contacts a roller  130  which is supported by a pair of tabs  134  which are attached to the outer tube  30 . Slots are formed in the inner tube  34  and outer tube  30  to allow the lever  42  and cam  122  to pivot. The lever  42  is shown rotated away from the rear leg  18  such that the inner tube  34  is retracted into the outer tube  30 . As the lever  42  and cam  122  are pivoted in a clockwise direction towards the rear leg  18 , the interaction between the cam  122  and the roller  130  pushes the inner tube  34  outwardly so as to lengthen the rear leg  18 . The cam  122  has a segment  138  which, when the lever  42  is moved adjacent the rear leg  18 , allows the inner tube  34  to retract slightly into the outer tube  30  from the maximum extended position such that the lever  42  and cam  122  are biased in a clockwise direction against the rear leg  18 . The segment  138  of the cam  122  causes the weight of the wire spool to lock the rear leg  18  into an extended position. 
     A third hole  142  may be formed in the clamping portion  54  of the jaw  46  to accommodate a third size of axle, if desired. The jaw  46  may be sized such that the three holes  70 ,  74 ,  142  are used to hold 1.5 inch, 2 inch, and 2.5 inch axles in the jaw. 
       FIG. 3  shows a side view of the stand  10  with the rear leg  18  in an extended position. It can be appreciated how lengthening the rear leg  18  will raise the axle  118  relative to the base  14 , and thus lift a spool of wire off of the ground. The lever  42  and cam  122  and the positioning of the front leg  82  and rear leg  18  provide a high degree of mechanical advantage in lifting a spool of wire, and allow a single person to lift a spool of wire weighing a few thousand pounds or more. 
     The jaw  46  is closed around an axle  118 . As such, the pin  66  is placed through a hole such as hole  74  in the clamping portion  54  and the hole  78  in the base portion  50 . In such a position, the axle  118  contacts the bearings  62  and will turn freely as the wire is pulled from the spool. 
       FIG. 4  shows another side view of the stand  10 , showing the stand in use with an axle  118  which has a smaller diameter than that shown in  FIG. 3 . To accommodate a smaller diameter axle  118 , the pin  66  is placed through a hole such as hole  70  in the clamping portion  54  and through hole  78  in the base portion  50  of the jaw  46 . As shown, the clamping portion  54  of the jaw  46  has multiple holes  70 ,  74  for holding the jaw closed around various sizes of axles as is desired. As discussed, a third hole  142  may be formed in the clamping portion  54  to accommodate three axle sizes, if desired. 
       FIG. 5  shows a perspective view of the jaw  46  in an open position. It can be seen how the base portion  50  and clamping portion  54  may include two sides (indicated with suffixes a and b) which are spaced apart and used to keep the axle  118  held perpendicular to the stand  10 . As such, each side (a and b) of the clamping portion  54  and base portion  50  includes the holes  70 ,  74 ,  78 , bearings  62 , pivot  58 , etc. The use of two sets of bearings  62  which are spaced laterally apart holds the axle perpendicular to the stand  10  and thereby keeps the stand from falling over laterally while in use. The stand  10  utilizes a long base and front and back legs  18 ,  82  which triangulate the jaw  46  and axle  118  above the base to provide front to back stability and prevent the spool of wire and stand from being pulled over forwards while in use. 
       FIG. 6  shows a perspective view of a stand  10  in a collapsed position for storage or transportation. In order to collapse the stand  10 , the telescoping sections of the front leg  82  are collapsed in order to minimize the length of the front leg. The post  110  at the bottom of the front leg is removed from the base  14  and the front leg is pivoted at pivot  106  to place the front leg against the rear leg  18 . The lever  42  is moved against the rear leg  18 , extending the rear leg, and the rear leg  18  and front leg  82  are pivoted together via pivot  22  so as to place the front and rear legs adjacent the base  14 . The jaw  46  is held closed by pin  66 . 
     In such a position, a typical embodiment of the stand  10  is about 3 feet long, 4 inches wide, and 8 inches tall. Such as stand  10  is capable of holding  5  foot spools of wire when extended for use. The stand  10  is thus advantageous as it provides a very small collapsed size which is easily placed in a vehicle for transportation, and which will easily fit in many locations for storage. When transporting a stand  10 , the person will often also be transporting wire, pulling rope, a wire puller, tools, etc. It is thus particularly important to provide a stand  10  which folds up into a compact size so that all of the necessary equipment may be transported easily. The long and narrow collapsed shape of the stand  10  is also advantageous as it helps keep the stand  10  from getting tangled up with the wire or rope which is being transported therewith. The stand  10  is thus advantageous as it is compact and easily transported and is still able to accommodate very large and heavy spools of wire. 
     The relatively simple design of the stand  10  provides a stand which weighs about 12 pounds, but which can support more than a thousand pounds each and which allows a person to quickly and easily lift a two thousand pound spool of wire off of the ground without any additional tools or power source. 
       FIG. 7  shows a perspective view of a pair of stands  10  used to support a spool of wire  146 . Typically, two stands  10  are used to support either end of an axle  118  which is passed through the center of a spool of wire  146 . In order to lift and support a spool of wire  146 , an axle  118  is first passed through the spool. A stand  10  is placed on either end of the axle. Each stand  10  is placed upright with the base  14  on the ground. The lever  42  is moved away from the rear leg  18  to retract the inner tube  34 , and the rear leg  18  is pivoted upwardly at pivot  22  until the jaw  46  is at about the height of the axle  118 . The length of the telescoping front leg  82  is then adjusted via pin  102  and the pin  110  is placed in a hole  114  in the base  14  such that the jaw  46  is at or slightly below the height of the axle  118 . 
     The jaw  46  is opened by removing pin  66  and pivoting the clamping portion  54  away from the base portion  50  at pivot  58 . The axle  118  is placed in the jaw  46 , and the jaw is closed and held in place with pin  66 . Once both stands  10  are in place on either end of the conduit, the lever  42  of each stand  10  is pivoted downwardly towards the rear leg  18  to extend the rear leg  18  and raise the spool  146  off of the ground. In order to minimize side loads placed on the stands  10 , the stands are typically used on a level surface, and the front leg  82  on each stand is extended to the same length and secured to the same hole  114  in the base  14 . 
     The stand  10  is advantageous as a pair of stands  10  may be set up and used to lift a spool of wire  146  in only a few minutes. The stand  10  is also very convenient to use, requiring no tools and providing a very simple set up procedure. A single person can use two of the stands  10  to safely and easily raise a spool of wire  146  off of the ground and secure the spool of wire for installing wire in a conduit. 
     The base  14  of the stand  10  is about 3 feet long, and as such provides a secure stand  10  which is not easily pulled over when pulling wire off of the spool  146 . The bearings  62  minimize the force required to pull wire off of the spool  146 , minimizing the loads placed on the stand  10  during use. As discussed, the jaw  46  holds the axle  118  perpendicular to the stand  10  and prevents the stands  10  from falling over sideways under the weight of the spool of wire  146 . It will be appreciated that, if used properly, little side loads will be placed on the stands  10 . Although not always necessary, the stand  10  may be provided with rubber feet of the like attached to the base  14  to prevent the stand from sliding on the floor during use. 
     The stand  10  may also include various other types of jacks in place of the cam action jack  38  which is shown. The cam may be replaced with a hydraulic jack such as a bottle jack, a mechanical screw jack, or a mechanical ratcheting jack. These different types of jacks may be used to increase the amount of weight that a person can easily lift, allowing the stands  10  to be used with heavier spools of wire, etc. The cam action jack shown, however, is advantageous as it is self locking and provides a very quick movement to operate the stand and raise the spool of wire. In either case, the stand  10  is advantageous as it provides a more stable stand than available stands. The wide base  14  and the jaw  46  securely hold the spool and help keep the stand from tipping over or releasing the spool accidentally. 
     While discussed specifically with spools of wire, it will be appreciated that the stand  10  is also useful for holding spools of rope (as may be used in pulling wire), spools of utility pipe or tube, or many other spools of material which are to be installed in a similar manner. 
     There is thus disclosed an improved stand for lifting and holding spools of wire and the like. It will be appreciated that numerous changes may be made to the present invention without departing from the scope of the claims.