Abstract:
A truck bed cargo barrier for use with a truck bed for stabilizing cargo items longitudinally and laterally. The cargo barrier is slidable relative to the front and back of the truck bed along a track system. The cargo barrier may be locked in a user specified position along the track system to accommodate the size of the load being carried forming a divider, or may be flipped up into a temporary storage position for linear cargo exceeding the length of the bed. Tie down brackets for bungee cords are adjustably attached to the barrier frame to secure cargo laterally. A barrier panel is connected to laterally adjustable, rigid side plates, each including two spaced apart wheels that ride on a pair of longitudinal tracks on the side walls of the truck bed. The spaced apart wheels firmly secure the barrier panel in a vertical position. A manual actuator permits manual positioning of the barrier panel along the bed frame front to back.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    This invention relates generally to an adjustable truck bed cargo organizer and divider and specifically to a manually adjustable, moveable truck bed cargo divider that is positionable along the length of the truck bed for securing in two directions individual cargo items.  
           [0003]    2. Description of Related Art  
           [0004]    A pick up truck typically has an open cargo bed. Unsecured cargo items or partial loads can move about the truck bed due to forces generated by turning, accelerating, stopping and riding over bumpy terrain. Truck bed dividers are used to secure partial loads in pickup trucks. Adjustable truck bed cargo dividers are known to secure and organize items placed within a truck bed in the longitudinal direction.  
           [0005]    An adjustable truck bed cargo divider is generally comprised of a thin planar barrier secured to a truck bed forming an enclosed volume where one or more items may be secured by the cargo divider and the truck bed&#39;s adjoining side walls.  
           [0006]    U.S. Pat. No. 5,427,486 issued to Green discloses an adjustable barrier device for securing a partial load in a load carrying area of a vehicle. The barrier uses spring-loaded elongated members that extend the width of the barrier and project outward of the barrier. The ends of the elongated members comprise friction pads for frictionally engaging the side walls of the load carrying area. These pads (and the barrier) may slide due to forces exerted by one or more cargo items being restrained during acceleration, braking, turning or riding over rough terrain.  
           [0007]    U.S. Pat. No. 5,586,850 issued to Johnson discloses a panel suspended by singular wheels from tracks mounted along the side rails of the truck bed. A second track system is employed along the floor of the truck bed for panel stability. The top of the panel is secured into position by a sliding bolt. The panel is also secured by a sliding bolt that engages slots contained in the second track along the floor of the truck. The bottom track prevents the panel from pivoting about the axis of the opposing wheels. The track system on the floor of the truck bed is susceptible to dirt and debris clogging the tracks and therefore does not allow the transport of granular materials such as gravel and soil in the truck bed.  
           [0008]    The present invention provides for an adjustable cargo divider system for use with a pickup truck bed that positively locks into place, is sturdy enough to hold cargo items securely in place, is easily moveable and adjustable to accommodate the size of the load being carried and allows the full or partial use of the truck bed, to stabilize cargo items in two dimensions, longitudinal and lateral.  
         BRIEF SUMMARY OF THE INVENTION  
         [0009]    An adjustable truck bed cargo divider for use with cargo items transportation in a truck bed which includes a rigid, planar cargo barrier and a pair of rigid wheel carrier side plates, each plate slideably attached perpendicularly to each end of the barrier. Each wheel side plate has two wheels, spaced apart. The barrier width based on the distance between the opposing wheel carrier side plates may be varied to accommodate for different sized truck beds of varying widths by telescoping each wheel carrier side plate within the cargo barrier frame. A wheel receiving track is attached at the top of each longitudinal side of the truck bed, either by a bolt-on adaptation as an accessory to a retractable truck bed cover manufactured by Roll-N-Lock Corporation in specially provided mounting holes or by clamp-on members when adapting to an open truck bed or truck bed having an alternative bed cover such as a vinyl tonneau system. The wheel carrier side plates are slidably secured by their pairs of wheels to respective side tracks so that the cargo barrier is rigidly maintained in a vertical position within the truck bed.  
           [0010]    The cargo barrier is maintained in a vertical position and prevented from pivoting by its attachment on each end to the wheel carrier side plates. The cargo barrier is elongated having a side plate attached at both ends so that the plane created by the cargo barrier is substantially perpendicular to the plane created by the side plates. The wheel carrier side plates are rigid, planar, and may be made of aluminum or other suitable material. The tops of the side plates extend lengthwise in relation to the tracks and are slidable along the tracks by the attachment of two separate wheels on each side plate for stability at either end of the top of each wheel carrier side plate. The side plates extend down in length on both sides of the cargo barrier and include a recess slot to receive an end portion of the barrier, thereby capturing and rigidly holding the cargo barrier which prevents the cargo barrier from pivoting due to forces which are exerted upon the cargo barrier by cargo items being restrained due to the truck braking, turning or riding over rough terrain. A triangular top support plate or gusset is horizontally engaged to the barrier and on top of one wheel carrier side plate. The gusset has a “unshaped” channel that engages the top surface of the barrier, extends forming a slidable channel which maintains the cargo barrier perpendicular to the side plate, preventing yawing as the barrier is moved along the tracks.  
           [0011]    The cargo barrier is a flat, rigid, somewhat rectangular panel having a tubular peripheral frame that extends longer along the top of the panel.  
           [0012]    Each wheel carrier side plate engages the barrier lateral top frame ends. Each plate has a perpendicular, rigid extension support arm that slides onto the top frame member of the barrier telescopically for lateral adjustment (different width beds), and is keyed (square extension arm and square panel slot) to prevent rotation of the wheel carrier side plate and the barrier frame.  
           [0013]    Each side plate extends down from the wheel mount and includes a vertical recess sized to approximate the thickness of the barrier panel for snug engaging and stabilizing the barrier panel to each side plate. Note, however, each side plate can be moved laterally (telescopically) to adjust for different wheel track separations on different trucks.  
           [0014]    Using a single barrier provides cargo security longitudinally along the truck bed, but does not address lateral or sideways movement of cargo. An important aspect of the invention is to secure individual cargo and individual items in two X/Y axes, longitudinally and laterally. In order to accomplish this, the barrier panel has a central lateral frame member that receives at least two slideable tie-off brackets that can engage stretchable bungee cords.  
           [0015]    In use, the cargo barrier is manually adjustable longitudinally and can be locked in place relative to the front or back of the truck bed in numerous, specific positions. The manual actuator is conveniently located on one side of the barrier top frame member. The pair of tie-off brackets are slidably attached to the cargo barrier middle frame member to conveniently provide a hook receiving eye for the purpose of attaching a rope, cord or elastic cord. Cargo items restrained longitudinally by the cargo barrier are further restrained laterally using the rope, cord or elastic cords secured to the tie-off brackets by hooks or knots after the cord is wrapped around a cargo item.  
           [0016]    When a cargo item is secured both longitudinally and laterally by the barrier and a tight (elastic) cord, vertical forces on the truck bed caused by bumps will not dislodge the cargo from the bed. Thus cargo is secured in three axes, i.e. x, y and z in Cartesian coordinates.  
           [0017]    The cargo barrier is locked (mechanically engaged) in position by manually-actuated, spring-loaded positioning lock bars which project outward from each end of the cargo top frame barrier and are aligned with and engage selected receiving apertures located along the side tracks. Each track body has a plurality of receiving apertures to allow the cargo barrier to be locked in several different longitudinal positions along the tracks. The track body apertures are aligned from side to side of the truck bed so that two lock bars engage two opposing track apertures for security of the barrier when locked in place. Alternatively, the vertical barrier may be easily removed for convenience by disengaging and removing all wheels from within their respective wheel tracks.  
           [0018]    On occasion, the vertical barrier may interfere with a unique or particular cargo item to be loaded into the bed. Therefore, vertical barrier may also be repositioned out of the way, if necessary, into a fixed, horizontal position. The user may disengage and remove two opposing wheels (one on each side plate) from within their respective wheel tracks and pivot the cargo barrier into a horizontal position about the axis created by the two remaining engaged wheels, allowing for convenient access beneath the pivoted barrier. An elongated cargo item such as a ladder may be placed in the cargo bed and not engage the barrier. The cargo barrier may be maintained in a horizontal position by pivot studs attached to each side plate which engage catch hooks along each track.  
           [0019]    It is an object of this invention to provide an adjustable cargo divider for use with a truck bed that positively manually locks into place, secures individual cargo items in two and three dimensions, is easily manually moveable and adjustable to accommodate the size of the load being carried and allows the full or partial use of the truck bed in carrying a variety of loads such as packages, sport gear, work equipment, supplies and can be flipped up into a temporary, out of the way, storage position for unusually long cargo that exceeds the length of the bed.  
           [0020]    In accordance with these and other objects which will become apparent hereinafter, the instant invention will now be described with particular reference to the accompanying drawings. 
       
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS  
       [0021]    [0021]FIG. 1 is a partially exploded, perspective view of the invention.  
         [0022]    [0022]FIG. 2 is a perspective view, partially cut away, of the first side plate engaged with the first track of the invention, with a cross section insert of the track.  
         [0023]    [0023]FIG. 3 is a side elevational view, partially cutaway, of one sidearm that is used to form the barrier in accordance with the present invention.  
         [0024]    [0024]FIG. 4 is a side elevational view of the manually activated clips attached to the lock bars of the invention, partially cut away.  
         [0025]    [0025]FIG. 5 is a section partial cross end elevational view of the cargo barrier showing tie-off brackets attached to the barrier lateral beams.  
         [0026]    [0026]FIG. 6 is a side elevational view of the first track of the invention illustrating the pivot feature of the barrier assembly, showing the barrier in a vertical position and a dotted horizontal position.  
         [0027]    [0027]FIG. 7 is a partially exploded front elevational view of the barrier assembly.  
         [0028]    [0028]FIG. 8 is a front elevational view in cross section of a universal track mount for a conventional truck bed.  
         [0029]    [0029]FIG. 9 is a perspective view of the invention installed within a truck bed. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0030]    Referring now to FIG. 1, the invention is shown as an adjustable cargo barrier system  10 . The adjustable cargo system  10  basically comprises a cargo barrier  20  having a first end  20   a  and a second end  20   b , a first track  30 , a second track  32 , a first wheel carrier side plate  40  and a second wheel carrier side plate  42 . The cargo system  10  is installed within a truck bed (bed floor  11 ) having a first side wall  11   a  and opposing second side wall  11   b  as seen in FIG. 9.  
         [0031]    The cargo barrier  20  is constructed of a top frame member  24 , a bottom frame member  28  (that is shorter in length than top member  24 ), a middle frame member  26  and a pair of end arm members  600   a  and  600   b  (FIG. 3) joined to the top, middle and bottom lateral members. The overall shape of the barrier is trapezoidal, the upper frame  24  being longer than the bottom frame  28  to accommodate the inwardly extending fender wells in some truck beds. Two barrier grid interior panels (upper  23  and lower  25 ) are slideably installed when the barrier  20  is manufactured between the top frame  24  and bottom frame  28  members and the middle frame member  26  (as seen in FIG. 5). These panels  23  and  25  can be solid fabric or have an open grid pattern as shown in FIG. 1. The upper frame member  24  also houses the manual barrier longitudinal locking mechanism, described in detail below. The barrier side arms  600   a  and  600   b  fit snugly within each side plate recess for structural rigidity.  
         [0032]    Referring now to FIG. 2, FIG. 3 and FIG. 7, opposing rigid planar first and second wheel carrier side plates  40  and  42  (shown in FIG. 2 without the barrier attached) are used to support the cargo barrier  20 . Barrier connecting bars  52  and  54  are attached at one end to each of first and second wheel carrier side plates  40  and  42  so that the bars  52  and  54  are perpendicular to the side plates  40  and  42  as seen in FIGS. 2 and 7. End arm members  600  have openings  610  that slideably receive connecting bars  52  and  54  at the first and second ends  20   a  and  20   b  of cargo barrier  20 . First side plate  40  is slideably attached to the first end  20   a  of cargo barrier  20  by bar  52  and second side plate  42  is slideably attached to the second end  20   b  by the insertion of the corresponding connecting bars  52  and  54  within end arm members  610  of cargo barrier  20  forming the barrier assembly.  
         [0033]    The side plates  40  and  42  are telescopically adjustable laterally to allow use of the barrier system with different sized truck beds. First side plate  40  and second side plate  42  are attached to cargo barrier  20  so that first and second side plates  40  and  42  are perpendicular to the cargo barrier  20 . The connecting bars  52  and  54  have a rectangular cross section (not circular) to key into the rectangular openings in end arm members  600   a  and  600   b  to prevent rotation between cargo barrier  20  and side plates  40  and  42 , firmly holding cargo barrier  20  in a vertical position.  
         [0034]    A top gusset  44  (FIG. 2) is fixedly attached to the top of first side plate  40  using bolt and nut fasteners  44   a . Gusset  44  extends horizontally above and connects slideably to cargo barrier  20  by the engagement of top frame member  24  in rectangular slot  44   b . Gusset  44  (mounted only on one side) greatly stabilizes the barrier  20  preventing raw movement and racking as the barrier is moved along the wheel tracks. First and second side plates  40  and  42  and gusset  44  are constructed of a strong metal such as an aluminum alloy, though any suitable strong material such as wood, metal or reinforced plastic may be used. The rigid wheel carrier side plates  40  and  42 , gusset  44 , the barrier frame members  24 ,  26  and  28 , the keyed connecting bars  50  and  52  and barrier arms  20   a  and  20   b  all work together to provide a sturdy, stable barrier.  
         [0035]    Referring to FIGS. 6 and 7, barrier  20  and side plates  40  and  42  are suspended from first track  30  and second track  32  by wheels  400 ,  401 ,  402  and  403  as illustrated in FIG. 1. Wheels  400  and  401  are rotationally attached to the upper outside area of first side plate  40  by bolts. Wheels  402  and  403  are attached to the upper outside area of second side plate  42  by bolts. Wheels  400  and  401  engage first track  30  such that first side plate  40  is supported by and can slide along first track  30  (FIG. 2). Similarly wheels  402  and  403  engage second track  32  such that second side plate  42  is supported by and can slide along second track  32 . The top areas of both first and second side plates  40  and  42  are purposely elongated to provide maximum wheel separation between the pair of wheels ( 400 , 401  and  402 , 403 ) on each side plate  40  and  42 . Because the barrier  20  is vertically mounted centrally between the front and back wheels on each side plate, each wheel is spaced sufficiently from the center of rotational moment of force if the barrier is forced to pivot, greatly resisting such pivotal force. The greater the wheel separation, the greater the resisting force movement.  
         [0036]    Referring now to FIG. 2, first and second tracks  30  and  32  are shaped in cross section like a “C” so that wheels  400 ,  401 ,  402 , and  403  are prevented from disengaging first and second tracks  30  and  32 . First and second side plates  40  and  42  are extended vertically from the top such that a rectangular slot is formed within each plate  40  and  42  which rigidly captures and holds cargo barrier  20  in place vertically. Barrier  20  is manually slidable by releasing the engaging lock relative to the front or back of the truck bed along first and second tracks  30  and  32 . Barrier  20  is prevented from sliding beyond the ends of first and second tracks  30  and  32  by releasable pins  46  located at the ends of first and second tracks  30  and  32  as seen in FIGS. 1 and 2. Releasable pins  46  prevent wheels  400 ,  401 ,  402  and  403  from traveling beyond the ends of first and second tracks  30  and  32 . Releasable pins  46  may be manually manipulated by pressing in the direction of arrow  46   a  allowing wheels  400 ,  401 ,  402  and  403  and the barrier  25  to be removed from the tracks.  
         [0037]    Referring to FIG. 1, first track  30  and second track  32  have downward longitudinal flange plates  30   a  and  32   a  respectively which extend from the track bottoms. Each flange plate  30   a  and  32   a  has a plurality of spaced apart apertures  300  (see FIG. 2), laterally juxtaposed below each track. The flange plate apertures  300  receive lock bar ends to lock the barrier at a fixed longitudinal position. Spring-loaded manually moveable lock bars  22  and  24  project outwardly from each end of the cargo barrier  20  and extend through holes in side plates  40  and  42  respectively. Lock bars  22  and  24  extend laterally within the top cargo barrier frame member  24  along a single axis. The end of each lock bar  22  and  24  can be inserted into the flange plate aperture  300  on each side of the truck bed and on each side of the barrier to lock the barrier in place by manipulating of the actuator tabs  220  and  240  shown in FIG. 1 by standing conveniently on one side of the truck bed.  
         [0038]    [0038]FIG. 4 shows the lock bar manual actuator having two finger engaging tabs  220  and  240  connected moveably to a spring mount rod  28   a  which is held by two spring retaining clips  22   a ,  24   a  attached to the ends of spring mount rod  28   a . Spring mount rod  28   a  retains spring  28  between tabs  220  and  240 . The lock bar actuator shown in FIG. 4 includes finger engaging tabs  220  and  240  that are squeezed together against spring tension from spring  28  that allows both lock bars to move inwardly, disengaging lock bars  22  and  24  free ends from the track apertures  300  permitting manual movement of the barrier divider longitudinally along the wheel tracks. Releasing tabs  220  and  240  allow spring  28  to expand, extending the free ends of lock bars  22  and  24  into engagement with the track flange and a specific pair of track apertures  300 , locking the barrier firmly in place. Tabs  220  and  240  regulate the travel of lock bars  22  and  24  so that they properly engage opposing receiving apertures  20   c  and  20   d  located along flanges  30   a  and  32   a  when fully extended due to the bias of spring  28 .  
         [0039]    Referring back to FIG. 1, the present invention is shown with a cargo item  500  such as a small cylindrical drum that can be secured by a bungee cord or elastic cord  262  by a pair of hooks that are secured or tied to the bungee or elastic cord  262  and which engage tie-off brackets  260  that are slideably attached to the middle frame member  26  so that the tie-off brackets may slide laterally. Tie-off brackets  260  are used to allow a flexible or regular cord or line to be attached to the bracket  260  so that a cargo item such as drum  500  can be secured tightly against the barrier  20 , thus securing cargo not only longitudinally with the barrier  20  but laterally. Each adjustable tie-off bracket  260  has a cross section that is C-shaped and engages the lipped area extending along the middle frame member  26  exterior for manual lateral movement as seen in FIG. 5. Although there are two tie-off brackets  260  shown, there could be additional brackets  260  for securing multiple or larger objects. In an alternative embodiment, additional tie-off brackets could also be added to the top frame member  24  if desired. FIG. 5 shows the bracket  260  which includes an aperture  260   b  that receives a hook, line, rope or plastic cord mounted on a lipped portion of middle frame  26 . Note that tie-off brackets  260  can be slideably mounted on both sides of middle frame member  26 .  
         [0040]    Referring now to FIG. 3, barrier sidearm  600   b  is shown. The barrier is assembled by having sidearms  600   a  and  600   b  on each end. Sidearms  600   a  and  600   b  each include stem  602  that is rectangular in cross section that fits into the open rectangular end of the top beam  24  while stem  604  fits into the middle beam  26  and the bottom stem  606  fits into the bottom frame member  28 . Thus sidearms  600   a  and  600   b  connect together the top, middle and bottom frames forming cargo barrier  20  (the center panels are separate pieces). The sidearm has many important functions and includes a projecting frame portion  612  that fits into a rectangular recess  40   a  (FIG. 6) within each side plate  40  and  42  (sideplate  40  is shown in FIG. 6) that prevents movement of the barrier  20  relative to side plates  40  and  42 . There is a snug fit between the outside portions of  612  and each side plate because of the side plate recess  40   a.    
         [0041]    Another important feature of sidearms  600   a  and  600   b  is that they have rectangular hollow openings  610  in the upper portion just below area  608  that telescopically receive connecting bars  52  and  54  respectively which extend from side plates  40  and  42 . Side plates  40  and  42  are slidably attached to sidearms  600   a  and  600   b  by insertion of connecting bars  52  and  54  within openings  610  of sidearms  600   a  and  600   b . Sidearm openings  610  are rectangular in cross section, preventing rotation relative to the sidearm opening  610 .  
         [0042]    Another function of sidearms  600   a  and  600   b  is that along and above the top section  608  is a lateral, cross member cap that fits on top of top frame member  24  that houses the lock bars and the lock bar actuator mechanism which fits above sidearms  600   a  and  600   b . Thus sidearms  600   a  and  600   b  each provides an important structural member of the invention.  
         [0043]    Referring now to FIG. 6, if the cargo item is sufficiently long to require full longitudinal access to the cargo bed such that the vertical barrier is in the way, the barrier can be moved to a horizontal position. In order to move the vertical barrier  20  from vertical operating position to a horizontal storage position, the user moves the barrier  20  to the farthest back position near the end of the truck bed gate at the ends of the wheel tracks. One side plate wheel on each side is removed from each track completely after pushing pins  46  out of the way. In its normal extended position in the wheel track, pin  46  prevents the wheels from leaving the tracks. (To remove the barrier from the wheel tracks, pins  46  are manually depressed and moved out of the track ends) The barrier  20  is manually rotated to a horizontal position about the wheel axes of the two opposing wheels still in the track. Stud  50  is positioned into catch hook  50   a  on each side of the truck bed. The barrier is now securely mounted horizontally away from the truck bed floor. The barrier cannot interfere with long items placed on the truck bed floor. Pivot studs  50  and pivot catch hooks  50   a  may be made of aluminum, steel or other suitable rigid material. First and second side plates  40  and  42  may vary in shape to allow the location of opposing pivot studs  50  to be positioned so that the desired pivot position of the cargo barrier  20  as maintained by opposing catch hooks  50   a  may be obtained.  
         [0044]    [0044]FIG. 8 shows a universal clamp assembly for a truck bed side wall to connect wheel tracks to the truck bed side wall. A first wheel track  30  and second wheel track  32  are fastened by bolts or clamps to the truck bed side walls so that the wheel tracks are parallel to one another. First wheel track  30  is longitudinally affixed to the top of the first side wall of the truck bed, and second wheel track  32  is longitudinally affixed to the top of the second side wall of the truck bed in one embodiment using several clamp assemblies  60  as seen in FIG. 8. Attachment flanges  30   b  and  32   b  extend from first track  30  and second track  32  respectively. Attachment flanges  30   b  and  32   b  engage and attach to several clamp assemblies  60 . Referring to FIG. 8, Each Clamp assembly  60  is formed by track clamp member  62  and bed clamp member  64 . Track clamp member  62  receives bed clamp member  64  within a bolt channel forming a “C” shaped clamp. Bolt  66  passes through an aperture in track clamp member  62  and is engaged by a threaded aperture within bed clamp member  64 . Clamp assembly  60  is assembled around the bed rail  11   b  of a truck bed. As bolt  66  is tightened, the distance between track clamp member  62  and bed clamp member  64  is reduced so that clamp assembly  60  positively engages the bed rail  11   b . A rubber mounting pad  62   a  is provided along the surface of track clamp member  62  which contacts the bed rail so that the bed rail finish is not damaged. Similarly, a rubber compression pad  64   a  is provided along the edge of bed clamp member  64  that contacts the bed rail. Second track  32  is adjustably attached to clamp assemblies  60  by bolt  68 . Attachment flanges  30   b  and  32   b  provide elongated holes that allow bolt  68  to pass through and secure first or second tracks  30  and  32  with clamp assemblies  60 . Parallel alignment of first and second tracks  30  and  32  is possible in trapezoidal truck beds by the elongated holes provided in flanges  30   b  and  32   b  which allow the installer to specify the attachment point of flanges  30   b  and  32   b  with clamp assembly  60 . The universal clamp system fits most truck bed rails. Some truck beds have original tonneau covers that include clamping systems that can be fitted with the present invention&#39;s wheel tracks.  
         [0045]    In a different embodiment, first and second tracks  30  and  32  may also be attached as an accessory to a retractable truck bed cover sold by Roll-N-Lock Corporation by bolts secured to specially provided mounting holes. The track is described in U.S. Pat. No. 5,251,950 owned by Roll-N-Lock Corporation, hereby incorporated by reference.  
         [0046]    [0046]FIG. 9 shows the invention vertically mounted in its operating position in a conventional truck bed having a bed floor  11  and truck bed walls  11   a  and  11   b . Tracks  30  and  32  are connected appropriately to the truckbed side walls as discussed above. The position of the barrier  20  can be adjusted along the longitudinal length of the truck bed by squeezing the barrier actuator and manually pulling or pushing the barrier along the rails  30  and  32  while continually engaging the finger tabs until the desired location is reached at which time the finger tabs are released allowing the lock bars to engage in opposing apertures within the wheel track flange. The lock bars are then spring-loaded in place once released, once the finger tabs have been released under the spring tension as described above.  
         [0047]    The instant invention has been shown and described herein in what is considered the most practical and preferred embodiment. It is recognized, however, that departures may be made from within the scope of the invention and that obvious modifications can be made by those ordinarily skilled in the art.