Abstract:
A mobile cart includes a first frame, and a second frame. The first frame includes a first base, first mover means coupled to the first base for providing mobility to the first frame, and a first upright support frame extending upwardly from the first base for supporting a first top, the first support frame including first engagement means. The second frame includes a second base, second mover means coupled to the second base for providing mobility to the second frame, and a second upright support frame extending upwardly from the second base for supporting a second top. The second support frame includes second engagement means cooperating with the primary engagement means for securing the second frame to the primary frame.

Description:
FIELD OF THE INVENTION  
       [0001]     The present invention relates to a mobile cart. In particular, the present invention relates to an extensible cart which can be field-modified in size and/or shape. This application claims priority from Canadian application no. 2,455,051.  
       BACKGROUND OF THE INVENTION  
       [0002]     Mobile carts are commonly used in warehouses for transporting articles of manufacture between loading/shipping bays and storage areas. Further, mobile carts are often equipped with bar-code readers and printers to allow such articles to be readily catalogued prior to storage and shipment. Also, mobile carts have been equipped with cash register terminals for use as check-out desks.  
         [0003]     Despite the widespread use of such carts, a common problem is that they tend to fixed in size and shape. Consequently, the cart manufacturer must maintain a variety of different designs to satisfy the varying needs of its customers. Conversely, if a cart customer&#39;s needs change, the customer must purchaser a new line of carts, even if the required change is only slight. Further, there may be several months lead time between the date a new design is requested and the date the redesigned cart is delivered to the customer. Accordingly, attempts have been made to design a mobile cart that in can be field-modified by the customer in response to the customer&#39;s changing needs.  
         [0004]     For instance, McCoy (U.S. Pat. No. 5,309,823), Chang (U.S. Pat. No. 5,299,817), Hodges (U.S. Pat. No. 5,599,031), Oefelein (U.S. Pat. No. 6,042,219) and Leverington (U.S. Pat. No. 6,263,031) developed extensible carts which are field-adaptable in size to the article to be transported. However, each extensible cart uses telescoping frame members to allow the size of the cart to be altered, thereby increasing the manufacturing cost and weight of the cart, and reducing its maneuverability. Further, clearance must be maintained between the telescoping frame members to allow the frame members to slide relative to one another, thereby compromising the rigidity of the cart, and reducing its load-carrying capacity. Therefore, the remains a need for a mobile cart that in can be easily field-modified by the customer in response to the customer&#39;s changing needs.  
       SUMMARY OF THE INVENTION  
       [0005]     According to the present invention, there is provided a mobile cart of modular design, which allows the size and shape of the cart to be modified by adding or removing frame components as required.  
         [0006]     In accordance with a first aspect of the invention, the mobile cart includes a base; mover means coupled to the base for providing mobility to the cart; a top; and a support frame extending upwardly from the base and supporting the top. The upright support frame includes engagement means for securing an auxiliary cart to the mobile cart.  
         [0007]     In accordance with a second aspect of the invention, the mobile cart includes a first frame, and a second frame. The first frame includes a first base, first mover means coupled to the first base for providing mobility to the first frame, and a first upright support frame extending upwardly from the first base for supporting a first top, the first support frame including first engagement means. The second frame includes a second base, second mover means coupled to the second base for providing mobility to the second frame, and a second upright support frame extending upwardly from the second base for supporting a second top. The second support frame includes second engagement means cooperating with the primary engagement means for securing the second frame to the primary frame.  
         [0008]     In one implementation of the invention, the first engagement means comprises a pair of stops, one of the stops being disposed adjacent the first base, the other of the stops being disposed adjacent the first top. The second engagement means comprises a pair of shoulders, one of the shoulders being disposed adjacent the second base, the other of the shoulders being disposed adjacent the second top, the shoulders pressing against the stops for securing the second frame to the first frame. The stops are positioned at opposite ends of the first upright support frame, and the shoulders are positioned at opposite ends of the second upright support frame, the shoulders being disposed between the stops. Also, the stops and the shoulders extend outwardly from the respective upright support frames, substantially parallel to the base.  
         [0009]     Preferably, the first frame has a substantially parallelopiped shape, the first base has four corners, and the first mover means comprises a caster wheel disposed at each respective corner. Each upright support frame comprises four elongate frame members, each said frame member including a plurality of parallel slots extending substantially parallel to the respective base for supporting movable shelving therein.  
         [0010]     Also, each shoulder is formed on a respective substantially horizontally-extending second stud panel, the second stud panels being secured to a pair of the respective elongate frame members. An uppermost one of the second stud panels is configured for removably securing the second top thereto, and a lowermost one of the stud panels including a channel for supporting a portion of the second base.  
         [0011]     Similarly, each stop is formed on a respective substantially horizontally-extending first stud panel, the first stud panels being secured to a pair of the respective elongate frame members. An uppermost one of the first stud panels is configured for removably securing the first top thereto, and the second top is substantially coplanar with the first top. The first and second tops comprise board facia paneling.  
         [0012]     Preferably, the upright support frames include a panel mounting bracket fastened thereto for securing substantially vertically-extending side facia paneling to the support frames. The facia paneling includes a mounting plate fastened thereto for removably securing the paneling to the respective panel mounting bracket. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]     The preferred embodiments of the invention will now be described, by way of example only, with referenced to the accompanying drawings, in which:  
         [0014]      FIG. 1  is a perspective view of one embodiment of the mobile cart, depicting the first frame, the second frame, and a shelf secured to the first frame;  
         [0015]      FIG. 2  includes front and side plan views of the mobile cart shown in  FIG. 1 ;  
         [0016]      FIG. 3  includes perspective, plan and end views of a top panel mounting bracket of the upright support frames of the first and second frames;  
         [0017]      FIG. 4  includes perspective, plan and end views of a back panel mount for interconnecting the elongate frame members of the upright support frames;  
         [0018]      FIG. 5  includes perspective, plan and end views of a side panel mounting bracket of the upright support frames;  
         [0019]      FIG. 6  is a perspective view of the second frame depicted in  FIG. 1 ;  
         [0020]      FIG. 7  includes front, side and bottom plan views and end views of the second frame depicted in  FIG. 6 ;  
         [0021]      FIG. 8  includes perspective, plan and end views of the base of the second frame;  
         [0022]      FIG. 9  includes perspective, plan and end views of one of the end frame assemblies of the second frame;  
         [0023]      FIG. 10  includes perspective, plan and end views of one the elongate frame members of the end frame assembly shown in  FIG. 9 ;  
         [0024]      FIG. 11  includes perspective, plan and end views of one of the horizontal stud members of the end frame assembly shown in  FIG. 9 ;  
         [0025]      FIG. 12  includes perspective, plan and end views of the other end frame assembly of the second frame;  
         [0026]      FIG. 13  includes perspective, plan and end views of the upper horizontal stud member of the end frame assembly shown in  FIG. 12 ;  
         [0027]      FIG. 14  includes perspective, plan and end views of one the elongate frame members of the end frame assembly shown in  FIG. 12 ;  
         [0028]      FIG. 15  includes perspective, plan and end views of the lower horizontal stud member of the end frame assembly shown in  FIG. 12 ;  
         [0029]      FIG. 16  is a perspective view of the first frame and the shelf depicted in  FIG. 1 ;  
         [0030]      FIG. 17  includes front and side plan views of the first frame depicted in  FIG. 16 ;  
         [0031]      FIG. 18  includes perspective, plan and end views of the shelf depicted in  FIG. 16 ;  
         [0032]      FIG. 19  includes perspective, plan and end views of the base of the first frame;  
         [0033]      FIG. 20  includes perspective, plan and end views of side facia paneling for attachment to the first and second frames;  
         [0034]      FIG. 21  includes perspective, plan and end views of top facia paneling for attachment to the first and second frames; and  
         [0035]      FIG. 22  is a perspective view of another embodiment of the mobile cart, depicting the first frame and shelf shown in  FIG. 1 , and a modified (narrower) second frame. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0000]     Mobile Cart  100   
         [0036]     Turning to  FIGS. 1 and 2 , a mobile cart, denoted generally as  100 , is shown comprising a first frame  200 , and a second frame  300  secured to the first frame  200 . Preferably, the first and second frames  200 ,  300  are stamped from steel, although other materials and manufacturing techniques may be used. As shown, the first frame  200  is secured to the left of the second frame  300 , however in one variation (not shown), the first frame  200  is secured to the right of the second frame  300 .  
         [0000]     First Frame  200   
         [0037]     The first frame  200  includes a first base  202 , and a first upright support frame  204  extending upwardly from the first base  202  for supporting a top  206  (see  FIG. 21 ) and vertically-extending side/rear panels  208  (see  FIG. 20 ). The first base  202  is shown in detail in  FIG. 19 , and the first upright support frame  204  is shown in detail in  FIG. 16 .  
         [0038]     Preferably, the first frame  200  has a substantially parallelopiped shape, and the first base  202  has a substantially rectangular shape. Alternately, however, the first base  202  and the first frame  200  may have a different shape to impart a different appearance to the first frame  200 . For instance, the first base  202  may have a sector shape to provide the first frame  200  with an arcuate appearance.  
         [0039]     As shown in  FIG. 19 , the first base  202  has a pair of opposite ends. The underside of the first base  202  includes a first mounting plate  210   a , and a second mounting plate  210   b , each carrying first mover means for providing mobility to the first frame  200 . The mounting plates  210  are identical to one another, and a secured to the bottom surface of the first base  202 . The first mounting plate  210   a  is disposed adjacent one end of the first base  202 , and the second mounting plate  210   b  is disposed adjacent the opposite end of the first base  202 .  
         [0040]     Each mounting plate  210  includes a pair of opposite ends, and a through-hole at each opposite end thereof for securing the first mover means to the mounting plate  210  (and therefore to the first base  202 ). Preferably, the first mover means comprises a pair of caster wheels (not shown) secured to the mounting plate  210 , each secured to the mounting plate  210  through a respective one of the through-holes. Accordingly, when the first frame  200  is assembled, the first frame  200  includes a caster wheel disposed at each corner of the first base  202 .  
         [0041]     As shown in  FIG. 16 , the first upright support frame  204  includes a first end frame assembly  216 , a second end frame assembly  218 , and a fixed shelf  220  extending between the end frame assemblies  216 ,  218 . The end frame assemblies  216 ,  218  are substantially identical to one another, and extend upright from the top surface of the first base  202  at substantially right angles to the first base  202 .  
         [0042]     In the embodiment shown, the first end frame assembly  216  is secured to the left hand end of the first base  202 , above the mounting plate  210   a . The second end frame assembly  218  is secured to the right hand end of the first base  202 , above the mounting plate  210   b . However, if the first frame  200  is disposed to the right of the second frame  300 , the first end frame assembly  216  would be secured to the right hand end of the first base  202 , and the second end frame assembly  218  would be secured to the left end of the first base  202 . Hereafter, for convenience, the first end frame assembly  216  will be referenced as the left end frame assembly  216 , and the second end frame assembly  218  will be referenced as the right end frame assembly  218 .  
         [0043]     For enhanced rigidity, preferably the end frame assemblies  216 ,  218  are welded to the first base  202 . Alternately, however, for greater flexibility in shape/style, the end frame assemblies  216 ,  218  may be secured to the first base  202  with removable fasteners, such as steel screws or bolts, so as to allow the size of the first frame  200  to be altered by replacing the first base  202  with a different-sized first base  202 .  
         [0044]     As shown in  FIG. 9 , the end frame assemblies  216 ,  218  each comprise a pair of elongate frame members  222 , a pair of horizontal stud members  224 , and a horizontal panel mounting bracket  228  (see  FIG. 1 ). The elongate frame members  222  extend upwardly from adjacent corners of the first base  202 , at substantially right angles to the first base  202 . As shown in  FIGS. 9, 10  and  16 , each elongate frame member  222  includes a plurality of slots  230  disposed transversely to the longitudinal axis of the frame member  222 . The slots  230  extend parallel to one another substantially along the entire length of the elongate frame member  222 , and are sized to accept a corner of a movable shelf therein.  
         [0045]     As shown in  FIG. 11 , each horizontal stud member  224  comprises a pair of opposing right-angled channels  232 ,  234 . Each smaller channel  232  defines a stop  235  that extends outwardly from the frame members  222 , substantially parallel to the first base  202 . As will be explained, the stops  235  serve to secure the second frame  300  to the first frame  200 .  
         [0046]     The larger channel  234  includes a pair of through-holes which allow the stud member  224  to be secured to the elongate frame members  222  with removable fasteners, such as steel screws or bolts. Each horizontal stud member  224  extends horizontally between the pair of elongate frame members  222 . One of the horizontal stud members  224  is fastened to the pair of elongate frame members  222  at one end thereof, and the other horizontal stud member  224  is fastened to the elongate frame members  222  at the other end. The horizontal stud members  224  are fastened to the elongate frame members  222  with an opposing orientation, such that the stop  235  of the upper horizontal stud member  224  is disposed at the uppermost end of the elongate frame members  222 , adjacent the top  206 , and the stop  235  of the lower horizontal stud member  224  is disposed at the lowermost end of the elongate frame members  222 , adjacent the first base  202 .  
         [0047]     For enhanced rigidity, preferably the horizontal stud members  224  are welded to the elongate frame members  222 , to thereby permanently secure the elongate frame members  222  together. Alternately, however, for greater flexibility in shape/style, the horizontal stud members  224  may be secured to the elongate frame members  222  with removable fasteners, such as steel screws or bolts, so as to allow the size of the first frame  200  to be altered.  
         [0048]     Each horizontal panel mounting bracket  228  is fastened to the upper horizontal stud member  224  at the uppermost end of the end frame assemblies  216 ,  218 . As shown in  FIG. 3 , the horizontal panel mounting bracket  228  comprises a right-angle flange. One arm of the flange includes a plurality of through-holes for securing the mounting bracket  228  to the upper horizontal stud member  224  via removable fasteners, such as steel screws or bolts. Preferably, the through-holes are elongate to facilitate self-alignment of the horizontal panel mounting bracket  228  to the end frame assemblies  216 ,  218 . The other arm of the flange includes a plurality of through-holes which allow the top panel  206  to be secured to the top of the first frame  200 , via the horizontal panel mounting bracket  228 .  
         [0049]     The left end frame assembly  216  includes an upper and a lower vertical panel mounting bracket  226  (the upper mounting bracket  226  is shown in  FIG. 1 ; the lower mounting bracket  226  is not shown, but is identical to location to the lower mounting bracket  226  secured to the second frame  300 ). As shown in  FIG. 5 . each vertical panel mounting bracket  226  comprises a right-angle channel  236  terminating at each channel side in a pair of right-angle flanges  238 ,  240 . The right-angle channel  236  is oriented vertically, and includes a plurality of through-holes for securing the panel mounting bracket  226  to one of the horizontal stud members  224  with removable fasteners, such as bolts. Similarly, the right-angle flanges  238 ,  240  are oriented vertically, and include a plurality of through-holes which allow the vertically-extending panels  208  to be secured to the sides of the first frame  200 , via the panel mounting brackets  226 .  
         [0050]     Each vertical panel mounting bracket  226  extends horizontally between the elongate frame members  222 , and is secured to the larger channel  234  of one of the horizontal stud members  224 . As a result, one of the panel mounting brackets  226  is disposed at the uppermost end of the elongate frame members  222 , adjacent the top  206 , and the other panel mounting bracket  226  is disposed at the lowermost end of the elongate frame members  222 , adjacent the first base  202 .  
         [0051]     As shown in  FIGS. 1, 16 , and  17 , the shelf  220  extends horizontally between the end frame assemblies  216 ,  218 , above the first base  202 , below the horizontal panel mounting brackets  228 . As shown in  FIG. 18 , the shelf  220  is substantially rectangular in shape, and includes a left hand end and right hand end. The shelf  220  also includes a first step  268 , and a second step  270  extending upwards from the rear of the first step  268 . The shelf  220  is secured at the left hand end to the elongate frame members  222  of the left end frame assembly  216 , and is secured at the right hand end to the elongate frame members  222  of the right end frame assembly  218 .  
         [0052]     For enhanced rigidity, preferably the shelf  220  is welded at its four corners to the elongate frame members  222 , thereby securing the end frame assemblies  216 ,  218  together. Alternately, however, for greater flexibility in shape/style, the shelf  220  may be secured to the end frame assemblies  216 ,  218  with removable fasteners, such as steel screws or bolts, so as to allow the size of the first frame  200  to be altered by replacing the shelf  220  (and the first base  202 ) with a different-sized shelf  220  (and first base  202 ).  
         [0000]     Second Frame  300   
         [0053]     The second frame  300  includes a second base  302 , and a second upright support frame  304  extending upwardly from the second base  302  for supporting a top and vertically-extending side/rear panels  208  (see  FIG. 20 ). The top supported by the second upright support frame  304  is typically the same continuous panel as the top  206  supported by the first upright support frame member  204 , however it can also be a panel separate from the top  206 .  
         [0054]     The second base  302  and the second upright support frame  304  are shown in detail in  FIGS. 6, 7  and  8 . Preferably, the second frame  300  has a substantially parallelopiped shape, and the second base  302  has a substantially rectangular shape. Alternately, however, the second base  302  and the second frame  300  may have a different shape to impart a different appearance to the first frame  300 . For instance, the second base  302  may have a sector shape to provide the second frame  300  with an arcuate appearance.  
         [0055]     As shown in  FIG. 8 , the underside of the second base  302  includes a mounting plate  310  disposed at one end of the second base  302  for securing second mover means to the second base  302  for providing mobility to the second frame  300 . Preferably, the second mover means comprises a pair of caster wheels (not shown) secured to the mounting plate  310 , each disposed at opposite ends of the mounting plate  310 .  
         [0056]     As shown in  FIGS. 6 and 7 , the second upright support frame  304  includes a first end frame assembly  316 , and a second end frame assembly  318 . Further, as shown in  FIG. 1 , the second upright support frame  304  also includes upper and lower back frame braces  320  extending between the first and second end frame assemblies  316 ,  318 . The end frame assemblies  316 ,  318  both extend upright from the second base  302  at substantially right angles to the second base  302 . The first end frame assembly  316  is secured to one end of the second base  302 , and the second end frame assembly  316  is secured to the opposite end of the second base  302 .  
         [0057]     For enhanced rigidity, preferably the end frame assemblies  316 ,  318  are welded to the second base  302 . Alternately, however, for greater flexibility in shape/style, the end frame assemblies  316 ,  318  may be secured to the second base  302  with removable fasteners, such as steel screws or bolts, so as to allow the size of the second frame  300  to be altered by replacing the second base  302  with a different-sized second base  302 .  
         [0058]     In the embodiment shown, the first end frame assembly  316  is secured to the right hand end of the second base  302 , above the mounting plate  310 , and the second end frame assembly  318  is secured to the left end of the second base  302 . However, if the first frame  200  is disposed to the right of the second frame  300 , the first end frame assembly  316  would be secured to the left hand end of the second base  302 , and the second end frame assembly  318  would be secured to the right end of the second base  302 . Hereafter, for convenience, the first end frame assembly  316  will be referenced as the right end frame assembly  316 , and the second end frame assembly  318  will be referenced as the left end frame assembly  318 .  
         [0059]     The right end frame assembly  316  is identical to the left end frame assembly  216  of the first frame  200 . The right end frame assembly  316  comprises a pair of the elongate frame members  222 , a pair of the horizontal stud members  224 , a pair of the vertical panel mounting brackets  226 , and the horizontal panel mounting bracket  228 . The elongate frame members  322  extend upwardly from adjacent corners of the second base  302 , at substantially right angles to the second base  302 . As shown in  FIGS. 6, 9  and  10 , each elongate frame member  222  includes a plurality of slots  230  disposed transversely to the longitudinal axis of the frame member  222 . The slots  230  extend parallel to one another substantially along the entire length of the elongate frame member  222 , and are sized to accept a corner of a movable shelf therein.  
         [0060]     As discussed above with reference to  FIG. 11 , each horizontal stud member  224  comprises a pair of opposing right-angled channels  232 ,  234 . As discussed above, the smaller channel  232  defines a stop  235  which serves to secure the second frame  300  to the first frame  200 . Each horizontal stud member  224  extends horizontally between the pair of elongate frame members  222 . The horizontal stud members  224  are fastened to the elongate frame members  222  with an opposing orientation, such that the stop  235  of the upper horizontal stud member  224  is disposed at the uppermost end of the elongate frame members  222 , adjacent the top  206 ′, and the stop  235  of the lower horizontal stud member  224  is disposed at the lowermost end of the elongate frame members  222 , adjacent the second base  302 .  
         [0061]     For enhanced rigidity, preferably the horizontal stud members  224  are welded to the elongate frame members  222 , to thereby permanently secure the elongate frame members  222  together. Alternately, however, for greater flexibility in shape/style, the horizontal stud members  224  may be secured to the elongate frame members  222  with removable fasteners, such as steel screws or bolts, so as to allow the size of the second frame  300  to be altered.  
         [0062]     As discussed above with reference to  FIG. 5 , each vertical panel mounting bracket  226  comprises a right-angle channel  236  terminating at each channel side in a pair of right-angle flanges  238 ,  240 . Each vertical panel mounting bracket  226  extends horizontally between the elongate frame members  222 , and is secured to the larger channel  234  of one of the horizontal stud members  224 . As a result, one of the panel mounting brackets  226  is disposed at the uppermost end of the elongate frame members  222 , adjacent the top  206 ′, and the other panel mounting bracket  226  is disposed at the lowermost end of the elongate frame members  222 , adjacent the second base  302 .  
         [0063]     The horizontal panel mounting bracket  228  is fastened to the upper horizontal stud member  224  at the uppermost end of the right end frame assembly  316 , opposite the similarly-located vertical panel mounting bracket  226 .  
         [0064]     The left end frame assembly  318  comprises a pair of elongate frame members  342 , an upper horizontal stud member  344 , and a lower horizontal stud member  346 . The elongate frame members  342  extend upwardly from adjacent corners of the second base  302 , at substantially right angles to the second base  302 . As shown in  FIGS. 6, 12  and  14 , each elongate frame member  342  includes a plurality of slots  348  disposed transversely to the axis of the frame member  342 . The slots  348  extend parallel to one another substantially along the entire length of the elongate frame member  342 , and are sized to accept a corner of a movable shelf therein.  
         [0065]     As shown in  FIG. 13 , the upper horizontal stud member  344  comprises a right-angled channel  350  terminating in a right-angle flange  352 . The right-angled channel  350  defines a shoulder  354  that extends outwardly from the frame members  342 , substantially parallel to the second base  302 . The right-angle flange  352  includes a plurality of through-holes which allow the top  206 ′ to be secured to the upper horizontal stud member  344 . Preferably, the top  206 ′ is secured to the upper horizontal stud member  344  with removable fasteners, such as steel screws or bolts. Further, preferably the through-holes are elongate to facilitate self-alignment of the top  206 ′ to the left end frame assembly  318 .  
         [0066]     As shown in  FIG. 15 , the lower horizontal stud member  346  comprises a right-angled channel  356  terminating in a right-angle flange  358 . The right-angled channel  356  includes a laterally-extending portion which serves to support the second base  302 . The right-angle flange  358  includes a plurality of through-holes which allow the stud member  346  to be secured to the pair of elongate frame members  342  with removable fasteners, such as steel screws or bolts. Also, the right-angle flange  358  defines a shoulder  360  that extends outwardly from the frame members  342 , substantially parallel to the second base  302 .  
         [0067]     The upper horizontal stud member  344  is fastened to the elongate frame members  342  at one end thereof, and the lower horizontal stud member  346  is fastened to the elongate frame members  342  at the other end. The upper and lower horizontal stud members  344 ,  346  are fastened to the elongate frame members  342  with an opposing orientation, such that the shoulder  354  of the upper horizontal stud member  344  is disposed near the uppermost end of the elongate frame members  342 , adjacent the top  206 ′, and the shoulder  360  of the lower horizontal stud member  346  is disposed near the lowermost end of the elongate frame members  342 , adjacent the second base  302 .  
         [0068]     For enhanced rigidity, preferably the horizontal stud members  344 ,  346  are welded to the elongate frame members  342 , to thereby permanently secure the elongate frame members  342  together. Alternately, however, for greater flexibility in shape/style, the horizontal stud members  344 ,  346  may be secured to the elongate frame members  342  with removable fasteners, such as steel screws or bolts, so as to allow the size of the second frame  300  to be altered.  
         [0069]     The back frame braces  320  extend horizontally between the end frame assemblies  316 ,  318 , securing the end frame assemblies  316 ,  318  together. As shown in  FIG. 4 , each back frame brace  320  comprises a right-angled channel  362  terminating in a right-angle flange  364 . The right-angled channel  362  includes laterally-extending edges that engage the slots  330 ,  348  of the elongate frame members  322 ,  342 . The right-angle flange  364  includes flaps  366  that are disposed at opposite ends of the brace  320  and extend at a right angle to the right-angle flange  364 . Each flap  366  includes a through-hole that allows the back frame brace  320  to be secured to the end frame assemblies  316 ,  318 , via the elongate frame members  322 . As shown, one of the flaps  366  is used to secure the back frame brace  320  to the rearward elongate frame member  322  of the right end frame assembly  316 , and the other flap  366  is used to secure the back frame brace  320  to the rearward elongate frame member  342  of the left end frame assembly  318 .  
         [0070]     One of the back frame braces  320  is fastened to the elongate frame members  222 ,  342  at one end thereof, and the other back frame brace  320  is fastened to the elongate frame members  222 ,  342  at the other end. As a result, one of the back frame braces  320  is disposed at the uppermost end of the elongate frame members  222 ,  342  adjacent the top  206 ′, and the other back frame brace  320  is disposed at the lowermost end of the elongate frame members  222 ,  342  adjacent the second base  302 .  
         [0071]     Preferably, the back frame braces  320  secured to the elongate frame members  222 ,  342  with removable fasteners, such as steel screws or bolts. Alternately, however, for enhanced rigidity, for greater flexibility in shape/style, the back frame braces  320  may be welded to the elongate frame members  222 ,  342 , to thereby permanently secure the end frame assemblies  316 ,  318  together.  
         [0072]     One of the aforementioned vertically-oriented panel mounting brackets  226  is secured to the right-angle flange  364  of each back frame brace  320  for allowing one of the vertically-extending panels  208  to be secured to the rear of the second frame  300 .  
         [0000]     Assembly of the Mobile Cart  100   
         [0073]     To assembly the mobile cart  100 , the assembler obtains one of the first frames  200  and one of the second frames  300 , and then directs the second frame  300  against the first frame  200  such that the left end frame assembly  318  of the second frame  300  is pressed against the right end frame assembly  318  of the first frame  200 . In this position, the shoulder  354  of the upper horizontal stud member  344  of the left end frame assembly  316  of the second frame  300  is positioned below the upper stop  235  of the right end frame assembly  218  of the first frame  200 . Conversely, the shoulder  360  of the lower horizontal stud member  346  of the left end frame assembly  316  of the second frame  300  is positioned above the lower stop  235  of the right end frame assembly  218  of the first frame  200 . As such, the shoulders  354 ,  360  are disposed vertically between the stops  235 .  
         [0074]     Thus, when the left end frame assembly  318  of the second frame  300  is pressed against the right end frame assembly  318  of the first frame  200 , the shoulder  354  frictionally engages the upper stop  235 , and the shoulder  360  frictionally engages the lower stop  235 , thereby helping to secure the second frame  300  to the first frame  200 . Further, the lower stop  235  supports the shoulder  360 , so that a portion of the load carried by the second frame  300  is carried by the first frame  200 . Removable fasteners, such as steel screws or bolts, are then threaded between the elongate frame members  222  of the right end frame assembly  218  of the first frame  200 , and the elongate frame members  342  of the left end frame assembly  318  of the second frame  300 , thereby rigidly securing the second frame  300  to the first frame  200 .  
         [0075]     The horizontal tops  206 ,  206 ′ ( FIG. 21 ) and the vertically-extending side/rear panels  208  ( FIG. 20 ) comprise board facia paneling. Further, the horizontal panels  206 ,  206 ′ and the vertical panels  208  each include a mounting plate (not shown) fastened thereto for removably securing the paneling to the respective panel mounting brackets  226 ,  228 . Thus, after the second frame  300  is secured to the first frame  200 , the horizontal tops  206 ,  206 ′ and the vertically-extending side/rear panels  208  are secured to the mobile cart  100  using removable fasteners, such as wood screws. As discussed above, the top  206 ′ carried by the second frame  300  is typically the same continuous panel as the top  206  supported by the first frame  200 , however it can also be a panel separate from the top  206 . If the top  206 ′ is separate from the top  206 , typically the top  206 ′ is substantially coplanar with the top  206 .  
         [0076]     This foregoing arrangement is advantageous since vertical movement of the second frame  300  relative to the first frame  200  is limited by the shoulders  354 ,  360  engaging the stops  235 , thereby limiting the shear forces acting on the removable fasteners. Further, since the mobile cart  100  is support by mover means (eg. caster wheels) near the right end frame assembly  218  of the first frame  200 , and is also support by mover means near the left end frame assembly  216  of the first frame  200  and the right end frame assembly  316  of the second frame  300 , the mobile cart  100  exhibits improved pivoting capabilities in comparison to conventional mobile carts.  
         [0077]     Further, the assembler can obtain another second frame  300 , and secure the left end frame assembly  318  of the new second frame  300  to the right end frame assembly  316  of the second frame  300  that is already secured to the first frame  200 . Additional second frames  300  can be cascaded together, in this manner, thereby allowing the assembler to increase the length of the mobile cart  100  simply by added additional second frames  300 . The assembly can also secure the left end frame assembly  318  of a new second frame  300  to the left end frame assembly  216  of the first frame  200 , thereby allowing the assembler to extend the length of the mobile cart  100  to the left and/or the right hand end of the first frame  200 .  
         [0078]     Also, since the panels  206 ,  206 ′,  208  include one or more mounting plates, the panels  206 ,  206 ′,  208  can be precisely fitted to the mobile cart  100  without significant manual effort. In addition, the mounting plates allow the panels  206 ,  206 ′,  208  to be easily replaced with different panels  206 ,  206 ′,  208 , as the decorative needs of the owner of the mobile cart  100  change.  
         [0079]     The present invention is defined by the claims appended hereto, with the foregoing description being illustrative of preferred embodiments of the invention. Persons of ordinary skill may envisage certain modifications to the described embodiments which, although not explicitly described or suggested herein, do not depart from the scope of the invention, as defined by the appended claims.