Abstract:
A portable collapsible cart for building materials comprises a wheeled platform with selectable hinged upright supports that are collapsible, thereby forming a compact unit for storage of the device. The cart will support and transport various bulky building materials. The cart is easily maneuverable by a single person due to swivel casters and a narrow upright design. The cart collapses to a low profile for storage and also provides removably attachable racks for transportation of long linear objects.

Description:
RELATED APPLICATIONS 
     The present invention is a Continuation-in-Part of and claims the benefit of U.S. application Ser. No. 12/629,304, filed Dec. 2, 2009, now abandoned the entire disclosures of which are incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates generally to carts for material transportation, and more particularly, to a collapsible portable cart for transporting large sheet material such as building materials. 
     BACKGROUND OF THE INVENTION 
     As anyone who performs a lot of physical work will attest, nothing beats having the proper tool for a job. The proper tool can save time, save money, produce a higher quality job, reduce damage to equipment, and provide for the increased safety of the worker. 
     Material handling is common requirement for various tasks and various material handling devices exist in an attempt to facilitate ease of transporting tools, equipment, or materials from one (1) location to another. In most cases, tools and large equipment can simply be rolled to the worksite on wheels, but materials typically have to be manhandled to the site. Materials that are heavy, wide and thin such as doors, plywood panels, countertops and the like pose an additional problem of bulk and awkwardness. While a hand truck or other transporting cart can be used to move such items in wide open areas, they are of no use in narrow areas such as hallways. Additionally, these devices are prone to damaging these materials during transport and require a considerable amount of space to store or carry which often times may be limited when transporting large amounts of materials from job to job. 
     Some devices have attempted to provide specialized features to increase the versatility of the transporting cart. U.S. Pat. No. 3,669,464, issued in the name of Linzmeier, describes a material cart which automatically aligns elongated materials that are placed upon it. The Linzmeier cart has a wheeled horizontal bed with side members and guide rails which perform the automatic alignment. 
     U.S. Pat. No. 4,165,088, issued in the name of Nelson, describes a combination cart having a horizontal flat deck with a plurality of receiving apertures which receive combinations of differing tubular carrying means depending upon the use and materials to be transported. 
     U.S. Pat. No. 4,953,878, issued in the name of Sbragia, describes a collapsible cart used for carrying groceries or other similar materials. The Sbragia cart utilizes an upper compartment having sidewalls and a lower planer area which may be folded to permit ease in transportability when not in use. 
     U.S. Pat. No. 5,584,635, issued in the name of Stapelmann, describes a carriage for a construction panel having a wheeled base and with an articulating frame for supporting panel materials. The frame moves relative to the base between a reclined position used during transport and an upright position used during installation of the panel material. 
     While these devices may fulfill their respective, particular objectives, each suffers from one (1) or more aforementioned disadvantages or deficiencies. Accordingly, there exists a need for a means by which heavy, thin and wide building materials can be easily moved without the disadvantages as described above. The development of the present invention substantially departs from the conventional solutions and in doing so fulfills this need. 
     SUMMARY OF THE INVENTION 
     In view of the foregoing references, the inventor recognized the aforementioned inherent problems and observed that there is a need for a means to easily and effectively transport large, heavy linear articles and thus, the object of the present invention is to solve the aforementioned disadvantages and provide for this need. 
     Another object of the present invention is to provide an easy to maneuver collapsible cart which is ideal transporting large sheet materials such as doors, plywood, drywall, countertops or the like to different locations without the risk of damaging the materials. 
     Another object of the present invention is to provide a versatile cart which can be utilized in a deployed configuration to transport large sheet materials or a substantially planer configuration to transport large articles such as furniture. 
     Yet still another object of the present invention is to provide a cart with a removable means of transporting long, thin articles such as rolled carpet, rods, or the like. 
     Yet still another object of the present invention is to provide a durable cart for handling materials which is easily and cost-effectively manufactured. 
     To achieve the above objectives, a feature of present invention provides a portable and collapsible cart for the transporting of materials comprising a substantially rigid and planer lower frame with at least one (1) wheel assembly, preferably attached to each corner. The lower frame has a rectangular configuration comprising an internal cavity with a depth defined by an upper horizontal surface and a lower horizontal surface. A left side supporting arm is pivotably connected to an interior vertical surface of the lower frame via a left side hinge mechanism, a right side supporting arm is pivotably connected to an interior vertical surface of the lower frame via a right side hinge mechanism, and a rear support brace is pivotably connected to an interior vertical surface of the lower frame via a rear hinge mechanism. The left side supporting arm and the right side supporting arm pivot about the lower frame in a direction perpendicular to a major axis of the lower frame. The rear support brace pivots about the lower frame in a direction parallel to the major axis of the lower frame. At least two (2) supporting braces are affixed to a lower edge of the lower frame perpendicular to the major axis of the lower frame. 
     Another feature of the present invention is to provide the rear support brace, the left side supporting arm, and the right side supporting arm further comprising a substantially vertical position relative to the lower frame defining a deployed configuration. 
     Another feature of the present invention is to provide the rear support brace, the left side supporting arm, and the right side supporting arm further comprising a substantially horizontal position relative to the lower frame defining a collapsed configuration. 
     Yet still another feature of the present invention is to provide hinge mechanisms which are mounted to the interior vertical surface of the lower frame at an offset distance such that the rear support brace and the side supporting arms unobstructedly pivot about the lower frame enabling the rear support brace and the side supporting arms to collapse into an interstitial area provided by an internal cavity of the lower frame. The cart further comprises a substantially planer horizontal surface when the rear support brace and the side supporting arms are in the substantially horizontal position. 
     Yet still another feature of the present invention is to provide the side supporting arms further comprising a structural supporting member pivotally connected to said lower frame and comprising an upper end and a lower end, a back supporting surface at a first inclined angle from horizontal and comprising an upper end connected to said structural supporting member with a first eyelet, a lower supporting surface perpendicularly connected to said back supporting surface, and a holding tab formed at a front portion of said lower end of said structural supporting member and connected to an end of said lower supporting surface opposing said back supporting surface for captivating said materials. 
     Yet still another feature of the present invention is to provide the side supporting arms further comprising a linear item support rack which is removably attached to the side supporting arms via an attachment means. Each of the linear item support racks further comprises at least one (1) perpendicularly attached support arm located at equivalent locations to provide an additional substantially horizontal support for linear materials. 
     Yet still another feature of the present invention is to provide the side at least one second eyelet affixed to at least one (1) support arm. 
     Yet still another feature of the present invention is to support and transport thin elongated material such as electrical wire rebar, or other similar material within the first eyelets and second eyelets. 
     The present invention provides a method of utilizing the transportable, collapsible cart that enables quick moving of many common building materials in a manner which quick, easy, effective and safe for both the user and the material. 
     Further objects and advantages of the present invention will become apparent from a consideration of the drawings and ensuing description. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The advantages and features of the present invention will become better understood with reference to the following more detailed description and claims taken in conjunction with the accompanying drawings, in which like elements are identified with like symbols, and in which: 
         FIG. 1  is an isometric view of a transportable and collapsible cart for building materials  10 , shown in a deployed and ready to utilize state, according to the preferred embodiment of the present invention; 
         FIG. 2  is an isometric view of the transportable and collapsible cart for building materials  10 , shown in a collapsed state, according to the preferred embodiment of the present invention; 
         FIG. 3  is an isometric view of the transportable and collapsible cart for building materials  10 , shown in a utilized state, according to the preferred embodiment of the present invention; 
         FIG. 4   a  is an isometric view of the transportable and collapsible cart for building materials  10 , with a pair of first linear item support racks  110  attached, according to the preferred embodiment of the present invention; 
         FIG. 4   b  is a partially exploded view of the transportable and collapsible cart for building materials  10 , depicting attachment/detachment of the first linear item support racks  110 , according to the preferred embodiment of the present invention; 
         FIG. 4   c  is a close-up view of upper collar  112  and lower bracket  113  portions of the invention, according to the preferred embodiment of the present invention; and, 
         FIG. 5  is an isometric view of a second linear item support rack portion  150  of the transportable and collapsible cart for building materials  10 , according to the preferred embodiment of the present invention. 
     
    
    
     DESCRIPTIVE KEY 
     
         
         
           
               10  transportable and collapsible cart for building materials 
               15  lower frame section 
               20  swivel caster 
               25  locking lever 
               30  left side supporting arm 
               35  left side hinge mechanism 
               40  right side supporting arm 
               45  right side hinge mechanism 
               50  rear support brace 
               52  floor panel 
               54  angle bracket 
               55  rear hinge mechanism 
               56  rear support cross-member 
               58  rear support vertical member 
               70  back support member 
               75  lower support member 
               77  first eyelet 
               80  holding tab 
               85  stud knob fastener 
               90  receiving fastener 
               95  large sheet material 
               100  first inclined angle 
               110  first linear item support rack 
               111  first support rack vertical member 
               112  first upper collar 
               113  first lower bracket 
               120  support arm 
               140  long linear objects 
               150  second linear item support rack 
               151  second support rack vertical member 
               152  second upper collar 
               153  second lower bracket 
               154  lower support arm 
               155  upper support arm 
               157  second eyelet 
           
         
       
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The best mode for carrying out the invention is presented in terms of its preferred embodiment, herein depicted within  FIGS. 1 through 4   c  and in terms of an alternate embodiment, herein depicted within  FIG. 5 . However, the invention is not limited to the described embodiment and a person skilled in the art will appreciate that many other embodiments of the invention are possible without deviating from the basic concept of the invention, and that any such work around will also fall under scope of this invention. It is envisioned that other styles and configurations of the present invention can be easily incorporated into the teachings of the present invention, and only one particular configuration shall be shown and described for purposes of clarity and disclosure and not by way of limitation of scope. 
     The terms “a” and “an” herein do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced items. 
     Referring now to  FIG. 1 , an isometric view of the transportable and collapsible cart for building materials (herein described as the “apparatus”)  10  shown here in a deployed and ready to utilize state according to the preferred embodiment of the present invention, is disclosed. The apparatus  10  comprises a lower frame section  15  and a removable/replaceable floor panel  52 . The lower frame section  15  comprises a rectangularly-shaped horizontal structure made using tubular steel for strength and durability, although other materials of construction may be considered, and as such, should not be interpreted as a limiting factor of the present invention. The lower frame section  15  comprises a plurality of inwardly protruding welded right-angle brackets  54  which provide a support means to the floor panel  52 , allowing said floor panel  52  to lay flat within the lower frame section  15 , thereby providing a flat surface capable of supporting various materials and equipment during use. The floor panel  52  is envisioned to be made using plywood or equivalent load-bearing material. 
     The apparatus  10  comprises four (4) swivel casters  20 , each located at each corner portion of the lower frame section  15  to provide support and maneuverability of the apparatus  10 . The swivel casters  20  allow the apparatus  10  to travel in any direction, thereby allowing the apparatus  10  to travel down narrow passageways and navigate tight turns and corners. Each swivel caster  20  is provided with a locking lever  25  to hold the apparatus  10  in position when loading or unloading materials and supplies. 
     The apparatus  10  comprises a “J”-shaped left side-supporting arm  30  which is connected along a bottom edge to the lower frame section  15  via a pair of left side hinge mechanisms  35 . Likewise, a “J”-shaped right side-supporting arm  40  is connected to an opposing side surface of the lower frame section  15  via a pair of right side hinge mechanisms  45 . Finally, a rear support brace  50  is connected to a rear edge of the lower frame section  15  via a pair of rear hinge mechanisms  55 . The left side hinge mechanisms  35 , the right side hinge mechanisms  45  and the rear hinge mechanisms  55  are vertically offset in their construction and mounting position upon said lower frame section  15  so as to facilitate collapsing of the left side supporting arm  30 , the right side supporting arm  40 , and the rear support brace  50 , compactly against the floor panel  52  for compact transporting and/or storage of the apparatus  10  (see  FIG. 2 ). 
     The rear support brace  50  comprises a rear-mounted unitary weldment which spans across, and supportingly attaches to the left side  30  and right side  40  supporting arms via respective stud knob fasteners  85 , thereby forming a three-sided load-bearing enclosure. The rear support brace  50  further comprises a rear brace cross-member  56  and a pair of rear support vertical members  58  which further comprise the rear hinge mechanisms  55  at bottom end portions. 
     The left side supporting arm  30  and the right side supporting arm  40  are each equipped with an integrally-welded back support member  70  and lower support member  75 . Each back  70  and lower  75  support member pair is welded together forming a relative angle of approximately ninety degrees (90°) being also welded to the left  30  and right  40  side supporting arms at a rearwardly inclined angle  100  of approximately ten degrees) (10°. The left  30  and right  40  side support arms are arranged in a parallel manner, thereby allowing a quantity of large sheet materials  95  to lean against said back  70  and lower  75  support member portions in a stable manner (see  FIG. 3 ). The back  70  and lower  75  support members define combined planar rear and bottom surfaces onto which said large sheet materials  95  may be placed. Furthermore, the lower end portion of each left  30  and right  40  side support arm, terminates slightly above respective lower support members  75  to form an upwardly extending holding tab  80  which acts to safely restrain loaded large sheet materials  95  upon said lower support members  75 . Said back  70  and lower  75  support members aid in retention of planar large sheet materials  95  such as sheets of drywall, sheets of plywood, doors, and other similar building materials, folded folding tables, and the like. 
     The left side  30  and right side  40  supporting arms provide a welded attachment to respective back support members  70  via respective integrated joining first eyelets  77 . The two (2) first eyelets  77  are located approximately six (6) inches below a top end portion of each back support member  70  being arranged along a common axis, thereby enabling insertion of an elongated rod, onto which spools of wire or similar materials may be hung. 
     The left side supporting arm  30  and the right side supporting arm  40  are affixed to the rear support brace  50  via respective stud knob fasteners  85  being mounted to outward-facing surfaces of said left side  30  and right side  40  supporting arms. The stud knob fasteners  85  comprise commercially-available hand-operated stud knob components having threaded shafts which penetrate through said left side  30  and right side  40  supporting arms and protrude inwardly from inner surfaces of said left side  30  and right side  40  supporting arms and in turn threadingly engaging corresponding threaded receiving fastener portions  90  being integrated into end portions of the rear brace cross-member portion  56  of the rear support brace  50 . However, other methods of fastening said left side  30  and right side  40  supporting arms to the rear support brace  50  such as latches, clamps, locking levers, and the like, could also be utilized with equal effectiveness and as such, should not be interpreted as a limiting factor of the present invention. The removable attachable function of the stud knob fasteners  85  and the receiving fasteners  90  allow easy detachment of the left  30  and right  40  side supporting arms from the rear support brace  50 , thereby allowing said portions to pivot downwardly and lie flat upon the floor panel  52 . The materials of construction are to provide the apparatus  10  with a weight carrying capacity of approximately one-thousand (1000) pounds. 
     Referring next to  FIG. 2 , an isometric view of the apparatus  10 , shown in a folded or retracted state, according to the preferred embodiment of the present invention, is depicted. This figure more clearly discloses the apparatus  10  in its collapsed state as the left side supporting arm  30 , the right side supporting arm  40 , and the rear support brace  50  have been pivoted inwardly and are resting upon the recessed floor panel  52  within the lower frame section  15 . Additionally, the compact and compressed shape of the apparatus  10  depicts the ease upon which the apparatus  10  may be picked up and carried, such as up and down stairs, as well as the ease upon which the apparatus  10  can be stored in a small location, either by lying the apparatus  10  flat, or standing it up on end. 
     Referring now to  FIG. 3 , an isometric view of the apparatus  10 , shown in a utilized state, according to the preferred embodiment of the present invention, is disclosed. The floor panel  52  has been removed from this figure to better illustrate the supporting angle brackets  54 . The angle brackets  54  provide bottom support to the floor panel  52  (see  FIG. 1 ). Said angle brackets  54  comprise a plurality of right-angle members arranged in an equally-spaced manner and welded along inwardly-facing surfaces of the lower frame section  15 , thereby allowing the removable floor panel  52  to lay flat. 
     This figure more clearly displays the ability of the apparatus  10  to store and transport a quantity of large sheet materials  95 . The large sheet materials  95  can be of various shapes and/or sizes, but are most likely to be sheets of plywood, sheets of drywall, sheets of paneling, collapsed folding tables, countertops, doors, or the like. The quantity of large sheet materials  95  that are held by the apparatus  10  is limited by the length of the lower support member  75  between the back support member  70  and the holding tab  80 . The large sheet materials  95  are positioned on the lower support member  75  at the first inclined angle  100  envisioned to be approximately ten degrees (10°). Such a configuration of the back  70  and lower  75  support members positions the large sheet materials in a slightly inclined and generally upright orientation enabling easy maneuvering down narrow hallways, on and off elevators, up to loading docks, and the like. Additionally, a forklift may be utilized to manipulate the apparatus  10  along with loaded materials, for placement at different elevations. Normal movement of the apparatus  10  upon the swivel casters  20  is provided by applying manual hand pressure to the apparatus  10  and/or the large sheet materials  95  to obtain motion in a desired direction. 
     Referring now to  FIGS. 4   a ,  4   b , and  4   c , various views of a first linear item support rack  110  attached to the apparatus  10 , according to the preferred embodiment of the present invention, is disclosed. The first linear item support rack  110  is provided in pairs and is attached to respective left side supporting arm  30  and right side supporting arm  40  portions. Each first linear item support rack  110  comprises a first support rack vertical member  111  and a support arm  120 . Said front support rack vertical member  111  comprises a length of rectangular tubing providing perpendicular welded attachment of the support arm  120 , an integral first upper collar  112 , and an integral first lower bracket  113 . The first upper collar  112  comprises a rectangular section of tubing being welded to a side surface being particularly sized to snuggly fit over a top end portion of the back support member  70 . The first lower bracket  113  comprises a pair of parallel welded appendages separated so as to snuggly fit over and laterally engage the lower support member  75 . In use, the first upper collar  112  and first lower bracket  113  engage respective back support  70  and lower support  75  members in a coincidental manner to secure the first linear item support rack  110  in place upon said left side  30  and right side  40  supporting arms. Other methods of attaching the first linear item support rack  110  such as screws, bolts, locking levers and the like can also be considered due to their equivalent functionality, and as such, should not be interpreted as a limiting factor of the present invention. 
     Each first linear item support rack  110  comprises a single support arm  120  capable of supporting a quantity of linear building materials  140 . The support arm  120  is welded to and made of similar materials as the first support rack vertical member  111 , and extends in a generally perpendicular direction outwardly from an intermediate location upon the first support rack vertical member portion  111 . Each support arm  120  of the pair of first support rack  110 , when installed on both left side  30  and right side  40  supporting arms is provided at a common equivalent elevation along a common plane, thereby supporting said linear building materials  140  at a stable horizontal orientation. The support arm  120  extends outwardly from the first support rack vertical member  111  parallel to the subjacent lower support member  75 . The inclination of the support arm  120  aids in the retaining of long linear objects  140  such as pipe, conduit, metal rods, rolled carpet and other long linear items commonly used in the building and construction trades. 
     The linear item support racks  110 ,  150  are designed to remain attached to the back support member  70  when folded downwardly against the floor panel  52  as an extension of said back support member  70 . 
     Referring now to  FIG. 5 , an isometric view of a second linear item support rack  150 , according to an alternate embodiment of the present invention, is disclosed. The apparatus  10  may be configured in various manners providing particular usefulness to different trades and applications. The second linear item support rack  150  is envisioned to be utilized as a pair of units to provide specialized features suitable to electrical conduit installation. Said second linear item support rack  150  comprises welded-on features including a pair of support arms  120  and a pair of second eyelets  157 . The support arms  120  are affixed at different elevations along the second support rack vertical member  151  and having a respective second eyelet  157  welded at an intersection of said second support rack vertical member  151  and a bottom surface of the support arm  120 , thereby acting as a receiving means for a long rod onto which spools of wire or similar materials may be hung. It is further understood that additional linear item support racks may be configured with various specialized features particularly suitable to other trades and projects without deviating from the concept and as such should not be interpreted as a limiting factor of the apparatus  10 . 
     It is envisioned that other styles and configurations of the present invention can be easily incorporated into the teachings of the present invention, and only one particular configuration shall be shown and described for purposes of clarity and disclosure and not by way of limitation of scope. 
     The preferred embodiment of the present invention can be utilized by the common user in a simple and effortless manner with little or no training. It is envisioned that the apparatus  10  would be constructed and utilized in general accordance with  FIG. 1  through  FIG. 4   c , as well as with the alternate second linear item support rack  150  shown on  FIG. 5 . 
     Upon initial utilization of the apparatus  10 , it would be decided upon which configuration of the apparatus  10  would be needed. For large sheet materials  95  such as drywall, sheets of plywood, doors, and other similar building materials, folded folding tables, and the like, the apparatus  10  would be configured and utilized as shown in  FIGS. 1 and 3 . For long linear objects  140  such as molding, pipe, conduit, rolled carpeting and the like, the apparatus  10  would be configured and utilized as shown in  FIG. 4   a.    
     The method of configuring and utilizing the preferred embodiment of the apparatus  10  may be achieved by performing the following steps: deploying the left side supporting arm  30 , the rear support brace  50 , and the right side supporting arm  40  in a sequential manner by pivoting said portions upwardly via respective left side hinge mechanisms  35 , rear hinge mechanisms  55 , and right side hinge mechanisms  45 ; threadingly engaging the two (2) stud knob fasteners  85  into the corresponding receiving fastener portions  90  of the rear support brace  50 ; placing and leaning a quantity of large sheet materials  95  onto the back  70  and lower  75  support members; pushing and therefore motioning the apparatus  10  in any desired direction using the omni-directional function of the swivel casters  20 ; motioning the apparatus  10  preferably in a direction being perpendicular to a short side of the lower frame section  15 , thereby allowing easy transporting of the apparatus  10  and loaded materials  95  down long narrow passageways such as hallways, and through doorways; arriving at an unloading destination; securing the apparatus  10  in place along a floor surface by locking the swivel casters  20  using the locking levers  25 ; unloading said large sheet materials  95  in an expected manner; repeating the above loading, transporting, and unloading process until a desired quantity of large sheet materials  95  has been moved; collapsing the apparatus  10  by loosening and disengaging the stud knob fasteners  85  from the receiving fasteners  90 ; sequentially folding the right side supporting arm  40 , the rear support brace  50 , and the left side supporting arm  30  downward against the floor panel  52 ; motioning the apparatus  10  either using the swivel casters  20  or picking up and carrying the apparatus  10  in a collapsed and compact form to a storage location until needed again; and, benefiting from a compact, maneuverable, and convenient means of transporting a large quantity of building materials  95 , afforded a user of the present invention  10 . 
     The method of configuring and utilizing the apparatus  10  when used in conjunction with attached support racks  110 ,  150  may be achieved by performing the following steps: deploying and securing the left side supporting arm  30 , the rear support brace  50 , and the right side supporting arm  40  as previously described above; attaching the first linear item support racks  110  or second linear item support racks  150  to the supporting arms  30 ,  40 , based upon a particular application or project, by coincidentally engaging the upper collar  112  and lower bracket  113  portions of each support rack  110 ,  150  with respective back  70  and lower  75  support members; utilizing the apparatus  10  to perform particular functions and tasks specific to a trade, project, or function, as desired; and, collapsing and storing the apparatus  10  as previously described. 
     The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention and method of use to the precise forms disclosed. Obviously many modifications and variations are possible in light of the above teaching. The embodiment was chosen and described in order to best explain the principles of the invention and its practical application, and to thereby enable others skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated. It is understood that various omissions or substitutions of equivalents are contemplated as circumstance may suggest or render expedient, but is intended to cover the application or implementation without departing from the spirit or scope of the claims of the present invention.