Abstract:
A collapsible and transportable dolly including first and second rigid base portions hingedly secured together at a central location. First and second pairs of wheels secure to underside locations associated with the base portions. First and second substantially rectangular and flame shaped end supports secure in upwardly extending fashion to opposite end locations of the hingedly connected base portions and first and second pairs of top brackets secure in interconnecting and hinged fashion between the end supports, and such that associated angled bracket portions extend from end locations of each of the top brackets and telescopically engaging the end supports. In this fashion, the doily is converted from a use to a folded storage/transport position by folding the base portions upwardly about the central hinged connection concurrent with inwardly and downwardly folding the top brackets concurrent with telescoping the angled brackets along end support channels.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present application claims the priority of U.S. Provisional Patent Application Ser. No. 60/826,397, filed Sep. 21, 2006, and entitled Collapsible and Portable Wheeled Dolly Particularly Suitable for use by Students or Others in the Transport of Items. 
     
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates generally to a collapsible and portable wheeled dolly or cart. More specifically the present invention discloses a collapsible dolly assembly suitable for being transported in a confined space, e.g. vehicle trunk, in a first storage position, and quickly converted to a wheel supported and three-dimensional space supporting use position to transport a plurality of items, such as those as which are associated with students or other individuals moving to a certain location, and by which it is desirable to be able to transport a number of items in a single trip. 
         [0004]    2. Description of the Prior Art 
         [0005]    The prior art is well documented with examples of foldable or convertible carts. The purpose of such convertible and wheel supported devices is to assist a user in quickly and conveniently transporting articles as a preferred alternative to carrying such items. 
         [0006]    A first example of a collapsible cart is set forth in U.S. Pat. No. 5,806,864, issued to Zielinski et al., and which exhibits four vertical legs with a plurality of shelves mounted thereupon. The shelves are rotatable relative to the legs and foldable about a middle thereof and so that the cart may be alternated between open/operable and closed/storage conditions. A plurality of locks stabilize the cart in the open position. 
         [0007]    U.S. Pat. No. 5,915,723, issued to Austin, teaches a collapsible utility cart including a frame having an upper pivotal component, a lower pivotal component and side components positioned therebetween, for converting the frame between extended and collapsed orientations. The frame further has wheels disposed in the corners thereof and an inner basket is dimensioned to be secured within the frame. A locking component is provided for locking the frame in the collapsed orientation and a telescopic handle is further pivotally coupled to the frame. 
         [0008]    U.S. Pat. No, 5,738,365, issued to McCarthy, teaches a collapsible cart including a base member, first and second double L-shaped brackets, a pair of locking pins, and two locking bar members. The locking bar members and locking pins are utilized to lock the double L-shaped brackets into place when the cart is in the un-collapsed configuration. 
         [0009]    A vet further example of a foldable laundry cart is disclosed in U.S. Pat. No. 5,772,236, issued to Clark, and in which a frame assembly includes an opening in which is fitted a basket. First and second leg assemblies are pivotally attached to opposite ends of the frame assembly, wherein the leg assemblies are foldable toward each other to a horizontal position adjacent the underside of the frame assembly whereby the cart can be easily stored when not in use. A tray assembly is swivelly attached to the frame assembly above the opening and a handle assembly extends from each end of the frame assembly wherein the handle assembly is adapted for use as a handle and a clothes hanging device. 
       SUMMARY OF THE PRESENT INVENTION 
       [0010]    The present invention discloses a collapsible and transportable dolly and which includes first and second rigid and substantially planar base portions hingedly secured together at a central location. First and second pairs of wheels secure to underside locations associated with the base portions in foldable fashion between inward/stowed and downward/deployed fashion. 
         [0011]    First and second substantially rectangular and frame shaped end supports secure in upwardly extending fashion to opposite end locations of the hingedly connected base portions and first and second pairs of top brackets secured in interconnecting and hinged fashion between the end supports. Associated angled bracket portions extend from end locations of each of the top brackets and telescopically engage the end supports. 
         [0012]    In this fashion, the dolly is converted from use to folded storage/transport positions, such as by folding the base portions upwardly about the central hinged connection, concurrent with inwardly and downwardly folding the top brackets and further concurrently with telescoping the angled brackets along the end support channels. 
         [0013]    Additional features include the first pair of wheels including swivelable wheels secured to a first end of the dolly, whereas the second pair of wheel further comprising fixed wheels secured to a second end. A lock release mechanism is associated with each of the fixed and swivelable wheels and, in cooperation with a support pin associated with wheel housings, permits the wheels to convert between use and rotated storage positions within a selected base portion underside. Mesh netting supports secure to respective sides and ends of the assembled dolly enclosure and assist in retaining of contents held within the supporting and defined interior. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]    Reference will now be made to the attached drawings., when read in combination with the following detailed description, wherein like reference numerals refer to like parts throughout the several views, and in which: 
           [0015]      FIG. 1  is an isometric perspective view of the dolly assembly according to a preferred embodiment of the present inventions and not illustrating the optional provision of side (e.g. mesh or netting) supports; 
           [0016]      FIG. 2  is an exploded view of the dolly assembly as illustrated in  FIG. 1 ; 
           [0017]      FIG. 3  is a top view of the present assembly; 
           [0018]      FIG. 4  is a side plan view of the present assembly; 
           [0019]      FIG. 5  is a selected end view of the present assembly: 
           [0020]      FIG. 6  is a bottom plan view of the present assembly: 
           [0021]      FIG. 7  is an isometric bottom perspective illustrating the dolly wheels extended; 
           [0022]      FIG. 8  is a corresponding isometric bottom view with the wheels folded; 
           [0023]      FIG. 9  illustrates a partially collapsed position of the assembly: 
           [0024]      FIG. 10  is an illustration in perspective of the dolly in a totally collapsed and portable condition; 
           [0025]      FIG. 11  is a top plan view of the collapsed dolly of  FIG. 10 : 
           [0026]      FIG. 12  is an end view of the collapsed dolly of  FIG. 11 ; 
           [0027]      FIG. 13  is a cutaway view taken along line  13 - 13  of  FIG. 11  and illustrating an exposed lengthwise extending center interior illustration of the collapsed dolly; 
           [0028]      FIG. 14  is a cutaway view taken along line  14 - 14  of  FIG. 11  and showing an exposed and lengthwise extending side rail illustration of the collapsed dolly; 
           [0029]      FIG. 15  is a top view of a partially collapsed dolly, such as shown in  FIG. 9 ; 
           [0030]      FIG. 16  is a cutaway view taken along line  16 - 16  of  FIG. 15  and illustrating the partially collapsed section through its top rail pivots, 
           [0031]      FIG. 17  is a further cutaway view taken along line  17 - 17  of  FIG. 15  and illustrating the top rail lock mechanism in side cutaway and exposed fashion; 
           [0032]      FIG. 18  is an enlarged partial view as illustrated in  FIG. 17  of the top rail support bracket lock pin in an engaged position with the lock mechanism; 
           [0033]      FIG. 19  is a successive illustration to that shown in  FIG. 18  and of the lock pin in a second release position: 
           [0034]      FIG. 20  is a further succeeding and partial illustration of the lock pin being advanced down a corresponding slot in the partially collapsed position; 
           [0035]      FIG. 21  is a bottom sectional perspective of a selected rotatable wheel in its use position; 
           [0036]      FIG. 22  is a cutaway illustration along line  22 - 22  of  FIG. 5  of a rotatable wheel; 
           [0037]      FIG. 23  is a further cutaway illustration along line  23 - 23  of  FIG. 5  of a further selected fixed or stationary wheel; 
           [0038]      FIG. 24  is an isometric views of a stationary wheel fold lock release along an indicated arrow direction; 
           [0039]      FIG. 25  is a further selected isometric view of a base located and center hinge lock release along a further indicated arrow direction: 
           [0040]      FIG. 26  is a further isometric view of a selected rotation wheel fold lock release along an indicated arrow direction: 
           [0041]      FIG. 27  is an enlarged partial isometric view illustration of a top rail lock mechanism release push button; 
           [0042]      FIG. 28  is an isometric perspective of the dolly assembly as substantially shown in  FIG. 1  and with side and end netting supports in place; 
           [0043]      FIG. 29  is a partially exploded illustration of the netting supports illustrated in respect to the dolly of  FIG. 28 ; 
           [0044]      FIG. 30  is a cutaway view taken along line  30 - 30  of  FIG. 3  and showing a sectional view through an associated end support and assembled end netting; 
           [0045]      FIG. 31  is an enlarged illustration from  FIG. 30  and showing the end netting at a top location with attachment rod. 
           [0046]      FIG. 32  is a further enlarged illustration from  FIG. 30  and showing the end netting at a bottom location associated hook attachment; 
           [0047]      FIG. 33  is an isometric detail of a selected rotatable (swivelable) wheel. 
           [0048]      FIG. 34  is a side view of the rotatable wheel in  FIG. 33 ; 
           [0049]      FIG. 35  is a cutaway view along interrupted line  35 - 35  of  FIG. 34  and showing at sectional view of the rotatable wheel detail; 
           [0050]      FIG. 36  is a sectional isometric view of a stationary wheel; 
           [0051]      FIG. 37  is a side view of the stationary wheel detail of  FIG. 36 ; 
           [0052]      FIG. 38  is a cutaway view along line  38 - 38  of  FIG. 37  and showing, the stationary wheel detail; 
           [0053]      FIG. 39  is a side view detail of a rotatable wheel and lock release; 
           [0054]      FIG. 40  is a cutaway view taken along line  40 - 40  of  FIG. 39  and showing the wheel detail and fold lock in an engaged position; 
           [0055]      FIG. 41  is a sectional view illustration of the wheel detail of  FIG. 40  and in particular of the fold lock in a released position; 
           [0056]      FIG. 47  is a yet further sectional view taken line  42 - 42  of  FIG. 4  and illustrating the base center fold hinge lock (established between the two pivoting planar shaped bases) in an engaged position; and 
           [0057]      FIG. 43  is a further succeeding illustration of the base center fold hinge lock of  FIG. 42  in a released and fold-permitting condition. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0058]    Referring now to  FIGS. 1 and 2 , respective isometric and exploded perspective views are illustrated generally at  10  of the foldable/convertible dolly assembly according to the present invention. As stated previously the dolly  10  shown in  FIGS. 1 and 27  does not illustrate the optional provision of side (e.g. mesh or netting) supports, this being further, illustrated and described in reference to the dolly as shown in the corresponding exploded views of  FIGS. 28 and 29  as will be subsequently described. 
         [0059]    The construction of the dolly  10 , as best illustrated in the exploded perspective of  FIG. 2 , is as generally follows and includes a pair of typically plastic or otherwise substantially rigid and planar shaped base portions  12  and  14  which are secured together at opposed hinged selected locations  16  and  18  (respectively) by a hinge support rod  20 . Hinge lock assemblies, generally referenced at  22  and  24  and as will be further described in detail are provided at opposing ends of the rigid base portions  12  and  14 , respectively, and to engage opposite ends of the hinge support rod  20  in selective locking or released positions. 
         [0060]    A pair of rectangular, frame shaped end supports  26  and  28  are provided, each typically also formed of a plastic or other durable and lightweight material and which are secured in upwardly extending fashion from opposite end locations of the planar shaped base portions  12  and  14 . First and second pairs  30  &amp;  32  and  34  &amp;  36  of top length extending brackets are provided and such that the respective pairs define hinged locations  38  and  40  therebetween. Additional angled brace supports are shown at  42 ,  44 ,  46  and  48  (each typically constructed of stainless steel or other suitable lightweight and strong material) extend respectively from opposite end locations of each of the top frame defining brackets  30 ,  32 ,  34  and  36 , to a respective angled mounting location with a selected inner facing location of each of the frame shaped end supports  26  and  28 . 
         [0061]    Release mechanisms associated with each of the end supports  26  and  28  and which as will be described subsequently permit vertical sliding displacement of connecting locations of each of the associated brace supports  42 ,  4 A,  46  and  48 ) are illustrated, respectively, at  50  &amp;  52  and  54  &amp;  56  with respect to end support  26  and further at  58  &amp;  60  and  62  &amp;  64  with respect to end support  28 . Inner top edge fascia covers are also illustrated at  66  and  68  and are provided in association with the top edge extending locations of the frame supports  26  and  28  and which hide a number of fastener receiving locations as shown in  FIG. 2 . 
         [0062]    A first pair of combined rotatable and swivelable wheels are shown at  70  and  72 , these being located in underside mounting fashion to a remote end of the rigid planar base portion  12 . The wheels  70  and  72  are secured by housing portions  74  &amp;  76  and  78  &amp;  80 , respectively, additional pins  82  and  84  being provided through associated housing supports  76  and  80  and which, in combination with corresponding lock pin assemblies  86  and  88  as will be further illustrated in additional detail, are actuated to inwardly rotate the wheels  70  and  72  to a stored position. 
         [0063]    A pair of fixed wheels  90  and  92  are located in likewise underside mounting fashion to an opposite remote end of the rigid base portion  14  and are housed within modified support portions  94  and  96 . A further pair of lock pins  98  and  100  are referenced and which, again in combination with release locks, of which a pair are illustrated at  102  and  104  defined in side extending locations of the rigid base supporting portions  12  and  14  in cooperation with selected rotated wheel  79  and fixed wheel  92 , enable the fixed wheels  90  and  92  to be rotated inwardly to the stored position. 
         [0064]    Also, additional end support pins are shown at  106  and  108  and which secure the remote ends of the rigid base portions  12  and  14  to corresponding bottom locations of the frame shaped end supports  26  and  28 . A central release lock  110  is provided for pivotally folding the rigid base portions  19  and  14  inwardly against one another upon actuating the opposingly arrayed pairs of hinge portions  22  and  24 . 
         [0065]    Referring further to  FIG. 6 , a bottom plan view is shown in better detail of a honeycomb or other suitable injection forming shaping provided to the rigid plastic undersides of components  12  and  14  and which provide the desired degree of strength to the assembly. Also better illustrated is the recessed configuration of an underside wheel well associated with each of the rotatable  70  and  72  and fixed  90  and  92  wheels and which serves to provide a flush configuration when the wheels are rotated about their respective mounting pins  82  &amp;  84  and  98  &amp;  100 , respectively, from the use position of  FIG. 7  to the folded transport position, as illustrated in  FIG. 8 . 
         [0066]    Referring now to  FIG. 9 , illustrated is a partially collapsed position of the assembly and by which the pairs of top frame defining brackets  30  &amp;  32  and  34  &amp;  36  are downwardly pivoted about central locations  38  and  40  (virtue of engaging release buttons  50 ,  54 ,  58  and  62  to allowing telescoping sliding of angled supports  42 ,  44 ,  46  and  48 ), in combination with the rigid bases  12  and  14  being inwardly and upwardly pivoted about its central hinged location  16  (by releasing lock pin  110 ), and in order to achieve the sandwiched arrangement of  FIGS. 10-12  illustrating in perspective of the dolly in a totally collapsed and portable condition.  FIG. 13  further illustrates a cutaway view taken along line  13 - 13  of  FIG. 11  and illustrating an exposed lengthwise extending center interior illustration of the collapsed dolly. 
         [0067]    Referencing now  FIG. 14 , a cutaway view taken along line  14 - 14  of  FIG. 11  shows an exposed and lengthwise extending side rail illustration of the collapsed and sandwiched dolly also shown in  FIG. 10 .  FIG. 15  further shows a top view of a partially collapsed dolly, such as shown in  FIG. 9 . 
         [0068]    Referencing now  FIG. 6 , a cutaway view take along line  16 - 16  of  FIG. 15  illustrates the partially collapsed section through its top rail pivots in cooperative fashion with that shown in  FIG. 9 . In particular, the vertical slotted arrangement defined in the sides of the frame portions  26  and  28  are shown, see as shown at  112  and  114  for angled brackets  42  and  44 , respectively, and which facilitate the downward and inward collapse of the pairs of top brackets (see as exemplified by hinged pair  30  and  32  in side plan illustration) in corresponding fashion to the upward and inward collapse of the rigid base portions  12  and  14 . 
         [0069]      FIG. 17  is a further cutaway view taken along line  17 - 17  of  FIG. 15 , similar in nature to that shown in  FIG. 16  and illustrates the top rail lock mechanism in side cutaway and exposed fashion in reference to the other pair of angled brackets  46  and  48  and associated pair  34  and  36  of hinged portions which traverse along additional vertical slots  116  and  118  in either of collapsing or opening directions. 
         [0070]    With reference to  FIG. 18 , an enlarged partial view is illustrated of a selected top rail support bracket lock pin and locking portion (see respectively at  58  and  60 ) selected from  FIG. 17 , and in an engaged position with the lock mechanism.  FIG. 19  is a successive illustration to that shown in  FIG. 18  and of the lock pin in a second release position and by virtue of the associated push button  58  being inwardly depressed, this causing the associated locking portion  60  to be inwardly displaced from a support ledge (see at  120 ) of selected angle bracket  48 , whereby the bracket  48  is then permitted to progressively telescope (see  FIG. 20 ) in advancing fashion down the corresponding slot in a collapsing direction.  FIG. 27  is an enlarged partial isometric view illustration of a top rail lock mechanism release push button, see again at  58 , and in order to release the selected illustrated, slidable and progressively telescoping bracket  48 . 
         [0071]      FIG. 21  illustrates a bottom sectional perspective of a selected rotatable wheel  70  in its use position and as previously described.  FIG. 22  illustrates is a cutaway illustration along line  22 - 22  of  FIG. 5  of rotatable wheel  72 , this providing an enhanced view of the manner in which the wheel  72  and its associated lousing portions  78  and  82  are rotated about the pin  84  engaged with the rigid support  12  underside.  FIG. 23  is a further cutaway illustration taken along line  23 - 23  of  FIG. 5 , of a further selected fixed or stationary wheel, by example shown as non-swivelable wheel  90 , and illustrating a similar arrangement by which a housing  94  and associated pin  98  are provided to rotate the wheel between the folded and use positions. 
         [0072]      FIG. 24  is a further isometric view of a stationary wheel fold lock release, see for wheel  92 , along an indicated arrow direction of  122  and in order to convert to a folded condition of the wheel. This is again accomplished by the release  104  working in cooperation with the pin support  100  to permit inward rotation of the wheel to the stored position. 
         [0073]      FIG. 25  shows a further selected isometric view of the base located and center hinge lock release  110  along a further indicated arrow direction  124 . Again, the rigid base sections  12  and  14  are allowed to converted to the folded position upon release of the lock release  110 . As further shown in  FIG. 26 , a further isometric view of a selected rotation wheel fold lock release is indicated by arrow  124 . 
         [0074]    As previously referenced,  FIG. 28  is an isometric perspective of the dolly assembly as substantially shown in  FIG. 1  and with side  128 ,  130 ,  132  and  134  and end  136  and  138  netting supports illustrated in place. The mesh netting sections shown represent only one possible variant of side and end support and, as further referenced in the partially exploded illustration of  FIG. 29 , the side extending and attachable portions  128  &amp;  130  and  132  &amp;  134  may at least each include top and bottom located channels (e.g. at  137  and  139  for selected portion  134  in  FIG. 29 ) for biasingly engaging to the tipper rails and rigid undersides of the dolly. 
         [0075]      FIG. 30  is a cutaway view taken along line  30 - 30  of  FIG. 3  and further showing a sectional view through a select associated end support netting  138 . Referring further to  FIG. 31 , an enlarged illustration from  FIG. 30  shows the selected end netting  138  at a top looped end  140  and support location an attachment rod  142 . As further shown in  FIG. 32 , is a further enlarged illustration from  FIG. 30  shows the end netting  138  at a bottom location associated hook attachment  144 . (See also  139  in  FIG. 20 ). 
         [0076]      FIG. 33  is an isometric detail of a selected rotatable (swivelable) wheel, e.g. an enlarged illustration of the wheel assembly  72  described in  FIG. 2 .  FIG. 34  is a side view of the rotatable wheel in  FIG. 33  and  FIG. 35  is a cutaway view along interrupted line  35 - 35  of  FIG. 34  and showing a sectional view of the rotatable wheel detail. 
         [0077]      FIG. 36  is a sectional isometric view of a stationary wheel such as correspondingly previously illustrated at  92  in  FIG. 2 .  FIG. 37  is a side view of the stationary wheel detail  92  of  FIG. 36  and  FIG. 38  is a cutaway view along line  38 - 38  of  FIG. 37  and shaving the stationary wheel detail. 
         [0078]      FIG. 39  is a side view detail of a rotatable wheel and lock release as previously described at  72  in  FIG. 2 .  FIG. 40  is a cutaway view taken along line  40 - 40  of  FIG. 39  and showing the wheel detail and fold lock in an engaged position, as also previously illustrated and described in the isometric underside perspective of  FIG. 8 . Of particular note, the wheel is removed from this view and to better show the interplay between the selected wheel release lock  86  and the associated rotating pin  82 . 
         [0079]      FIG. 41  further shows a sectional view illustration of the wheel detail of  FIG. 40  and in particular of the fold lock in a released position. A pair of locking tabs see at  57  and  89 , respectively interact with lockpin assemblies  86  and  88  (previously recited in  FIG. 2 ) and upon engaging, prevent the wheel assembly from rotating relative to the base platforms  12  &amp;  14 . It is further that the feature described above is also incorporated into the rear fixed wheel assemblies  90  &amp;  92 .  FIG. 42  is a yet further sectional view taken line  42 - 42  of  FIG. 4  and better illustrates the base center fold hinge lock (established between the two pivoting planar shaped bases) in an engaged position. Reference in particular is made to the looped end portion associated with the selected spring biasing portion  86  of the wheel release. Finally, and referencing  FIG. 43 , a further succeeding illustration of the base center fold hinge lock of  FIG. 42  is shown in a released and fold-permitting condition, this again being effectuated by the spring portion of release lock  86  being biased by actuation of the associated release  102  located in the side of the base portion (e.g. at  12 ), this further serving to unseat an inwardly projecting edge (see at  146  in each of FIGS.  40 ,  41 ,  42  and  43 ) from an associated receiving location associated with a rotatable wheel housing, thereby permitting the given fixed or rotatable wheel to be manually pivoted to the folded (or reopened) position. 
         [0080]    Having described my invention, other and additional preferred embodiments will become apparent to those skilled in the art to which it pertains, and without deviating from the scope of the appended claims.