Patent Publication Number: US-7896143-B2

Title: Selectively removable pull bar for a portable container

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of U.S. Provisional Application No. 60/972,040, entitled “SELECTIVELY REMOVABLE PULL BAR FOR A PORTABLE CONTAINER,” filed on Sep. 13, 2007, which is incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates generally to wheeled portable containers having pull bars and more particularly to collapsible frame luggage with selectively removable pull bars. 
     BACKGROUND INFORMATION 
     It is known in the art that adding wheels to portable containers, especially luggage, provides significant mobility improvements over non-wheeled containers. Even a very brief observance of an airport or train station demonstrates consumer preference for wheeled luggage. Including a pull bar and handle aides the operator of the portable container in maneuvering the same. The pull bar typically extends out from the container and thereby provides at least two advantages. The pull bar extends the handle up to a height of the operator&#39;s hand thereby removing the need for the operator to hunch or bend to reach the container. Additionally, a pull bar allows for the portable container to trail behind the operator providing clearance from the operator&#39;s legs and feet. 
     Many portable container designs, especially those for luggage, include two wheels disposed along a lower edge of the container. In such configuration, the container must pivot about the wheels and maintain in an angled position during transit to ensure that no portion of the container drags along the ground surface. The natural pendulum effect of human locomotion can result in a continuous oscillation of the pivot angle. The oscillation can result in shaking of the container and the contents therein. The oscillation can be prevented with additional manual intervention by the operator, and the additional manual intervention can be difficult for the operator to maintain over a long period of time. 
     Many portable containers with semi-rigid walls retain their shape even when empty. The internal void of a container can consume a significant volume of storage space. While other items could be stored within the container, this could increase the time required to pack, unpack, and store the container. 
     The pull bars of the portable containers are often stored by sliding into the body of the portable container against one of the side walls, which reduces the internal capacity. In such configuration, the location to stow the pull bar is inflexible. 
     SUMMARY 
     A portable container system includes a collapsible frame, a shell attached to the frame and defining a volume, wheels attached to the bottom of the frame, and a pull bar assembly comprising a removable attachment member that removably attaches the pull bar assembly to the frame. The removable attachment member is contractible so it disengages from the frame when contracted and it engages the frame when expanded. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       While the claims are not limited to the illustrated embodiments, an appreciation of various aspect of the current application is best gained through a discussion of various examples thereof. Referring now to the drawings, illustrative embodiments are shown in detail. Although the drawings represent the embodiments, the drawings are not necessarily to scale and certain features may be exaggerated to better illustrate and explain different aspects of an embodiment. Further, the embodiments described herein are not intended to be exhaustive or otherwise limiting or restricting to the precise form and configuration shown in the drawings and disclosed in the following detailed description. Exemplary embodiments of the present application are described in detail by referring to the drawings as follows. 
         FIG. 1  is a perspective view of a portable container including an exemplary pull bar in an attached extended position; 
         FIG. 2  is a perspective view of a portable container including an exemplary pull bar in an attached recessed position; 
         FIG. 3  is a frontal end view of a portable container including a more detailed view of an exemplary attachment member for a pull bar; 
         FIG. 4  is a perspective view of a portion of an exemplary pull bar and attachment member detached from a portable container; 
         FIG. 5  is an enlarged view of an exemplary pull bar assembly including a detached exemplary attachment member and cut away portions of a frame of a portable container. 
     
    
    
     DETAILED DESCRIPTOIN 
     This application generally relates to a portable container and more specifically relates to a mobile portable container having optionally storable pull bar. 
     The portable container may include additional wheels along the lower surface, such as at each of the four lower corners of the container, which would allow the container to be movable without pivoting. In such configuration all four wheels remain in contact with the ground surface. 
     The portable container may additionally include an attachable and pivotable pull bar to the container to further reduce the pendulum effect of the operator. 
     The portable container may also be a semi-rigid portable container that can collapse when storing. 
     Referring to  FIGS. 1 and 2 , a wheeled container  10  includes a frame  20  having collapsible side frames  22  with swivel and fixed castor wheels  70  attached thereto. A canvas shell  80  attaches to the frame  20  and may include a plurality of storage pockets  84 . A pull bar assembly  100  removably attaches to the frame  20  to facilitate movement of the container  10 . The pull bar  100  is selectively coupled to the frame  20  by an attachment member  130 , to be described in connection with  FIG. 3  below. 
     The collapsible frame  20  provides structure to the portable container  10  shown in  FIGS. 1 and 2 . The frame  20  includes first and second side frames  22 , which are generally symmetrically identical and therefore will be discussed simply as a side frame  22 . A plurality of frame segments attach end to end forming a rectangular side frame  22  having an upper  24  and lower  26  segments and front  28  and rear  30  segments may be configured in other manners. An elbow joint  50 ,  56 , or  60  at each of the four corners connects the ends of the frame segments. The symmetric side frames  22  attach to each other with jointed expansion brackets  32  along the front  28  and rear  30  frame segments. Selectively pivotable joints  34  (explained in further detail below) of the expansion brackets  32  enable the frame  20  to collapse. 
     The frame  20  may be constructed of suitable material to endure significant stresses from loads applied thereto. The material for the frame  20  may also provide protection to the content of the container  10 . The suitable material includes but not limited to fiber glass, steel, steel alloys, graphite, carbon fiber, titanium, and any combination thereof. For instance, during normal use container  10  can be stacked dropped, or sat upon. One embodiment includes tubular frame segments  24 - 30  made of fiber glass. While the use of fiber glass for the frame segments provides a significant degree of strength to the frame  20 , it should be apparent that various other materials may be employed. The frame  20  may be configured with higher strength materials to transport delicate contents. 
     The frame  20  has a generally rectangular form with the upper  24  and lower  26  frame segments defining a depth, the front  28  and rear  30  frame segments defining a height, and the expansion brackets  32  defining a first and second width. The first width represents the brackets  32  in their extended arrangement, while the second width represents the brackets  32  in a bent or collapsed arrangement such that the second width is less than the first width. Each expansion bracket  32  includes at least three pivot joints  34  connecting a first base  36 , a first span  38 , a second span  40 , and a second base  42 . In such a configuration, the first  38  and second spans  40  pivot from a linear arrangement in the extended configuration to a parallel arrangement in the collapsed configuration. While the base  36 ,  42  of each expansion bracket could reasonably attach to any number of positions along the side frame  22 , providing bases  36 ,  42  that are integrally molded with an elbow joint  56  is particular effective. The first  38  and second  40  spans of the expansion bracket  32  include a locking mechanism  44 . A thumb operable tab  46  interlocks the first and second span  38 ,  40  in the expanded position. Depressing the tab  46  releases the lock  44  and allows the bracket  32  to bend into the collapsed configuration. 
     Each side frame includes elbow joints  50 ,  56 , and  60  that connect the various frame segments  24 - 30 . One embodiment includes molded polymeric elbow joints. Each elbow joint includes a first socket  52  aligned with a first axis and a second socket  54  aligned with a second axis, wherein the first and second axes are generally perpendicular. Using  90  degree corners on the elbow joints  50 ,  56 , and  60  creates a generally rectangular shaped side frame  22 . One skilled in the art will appreciate that the angle between the first  52  and second  54  socket can vary for side frames  22  having different shapes. The elbow joint  56  that connects the upper frame segment  24  with the front frame segment  28  includes a third socket  58  configured to receive the attachment member  130  (discussed below). Including the sockets  58  for the attachment member  130  on the elbow joints  56  and castors  70  (discussed below) on the elbow joints  60  may simplify the tubular frame segments  24 - 30  by including the more intricate elements on the molded joints. 
     Additionally, the elbow joints  60  connecting to the lower frame segment  26  include an attachment hole for a castor  70 . Castors  70  are well known in the art for providing wheels having a significant degree of mobility. Castors  70  typically include an axel  72  supported wheel  74  with an attachment shaft  76  connected thereto. For swivel castors, one or more bearings (not shown) disposed about a shaft  76  allow for free rotation of the wheel  74  and axel  72  about the shaft  76 . In such a configuration, each swivel castor wheel  74  can rotate 360 degrees about in clock-wise or counter clock-wise direction of its attachment shaft  76 . Including a castor  70  at each lower corner allows for very flexible maneuverability. In one embodiment, the swivel castors  70  are provided at the lower front corners of the frame  20  generally below where the pull bar assembly  100  attaches to the frame  20 , and the fixed castors  70  are provided on the lower back corners of the frame  20 . The size and type of the attachment shaft  76  of the castor wheels can vary depending on the size of the wheel. Larger wheels can benefit from a bolt type shaft which is fixedly attached to the elbow joint with a washer and nut. Alternatively, the shaft of smaller castor wheels can simply be riveted to the elbow joint. Larger wheels are typically used with larger portable containers and therefore must be able to accommodate a greater load. Bolting the castor to the elbow joint provides additional strength to deal with any increased weight. Using a dense rubber or polymer wheel  74  on the castors  70  can provide a degree of shock absorption to the portable container. 
     A canvas shell  80  attaches to the frame segments  24 - 30  and provides a body to the portable container  10 . The canvas shell  80  may be made of synthetic or natural materials that may include but not limited to polyester, nylon, Teflon®, Gortex®, leather, synthetic leather, steel mesh, or in any combination thereof. With a rectangular frame  20 , the canvas shell  80  includes six side wall members  82  that enclose an internal void (not shown). The side wall members include various openings  84  that can be secured by various fastening means including zippers  86 , snaps, or tiebacks among others. The number and configuration of the openings can be varied based on the purpose of the portable container  10 . In one of the embodiments, a portable container configured to be a pet carrier can further including netting disposed beneath the flap openings. Accordingly, an enclosed pet can receive sufficient ventilation while removing any risk of escape. Similarly, various sets of internal dividers can compartmentalize the internal void as needed for different types of containers. While virtually any type of contents could be carried in such a container  10 , some specific configurations include shells  80  for use as a carrier, a stenographer case, and a photography equipment carrier. Edges between the wall members  82  that correspond with the frame  24 - 30  segments include elongated loops  90  of fabric. The frame segments  24 - 30  are inserted into the loops  90 . 
     The pull bar assembly  100  includes a first  102  and a second  104  parallel span connected at one end by a cross member  106  and at the opposing end by a removable attachment member  130 . A gripping surface may be disposed along the cross member  106  to assist the operator in gripping thereon. First  110  and second  112  expansion shafts can be respectively inserted within the first  102  and second  104  spans. The expansion shafts  110 ,  112  may slidingly fit concentrically within the spans  102 ,  104 . A first end of each expansion shaft includes a spring biased locking protrusion  114 . A hole  116  configured to receive the locking protrusion  114  is disposed on each span  102 ,  104 . A bore hole  118  extends laterally through an end of the expansion shafts  110 ,  112 . An end cap  120  closes off the open end of the expansion shaft and acts as a grommet to the lateral bore  118 . The operation of the expansion shafts  110 ,  112  involves sliding shafts out of the respective span  102 ,  104 . The locking protrusion  114  of each expansion shaft remains compressed against the inner surface of the span until the extension of the expansion shaft reaches the hole  116  along the span. When the protrusion  114  reaches the hole  116 , the biased locking protrusion engages the hole to halt the expansion. As shown in  FIG. 2 , the pull bar assembly  100  may be recessed between the side frames  22 . 
     The pull bar assembly  100  detaches from the portable container  10  for storage or any other need. An attachment member  130  links the pull bar assembly  100  to the frame  20 . In an embodiment of the attachment member  130 , the attachment member  130  includes an outer shaft  132 , an inner shaft  134 , and two stub shafts  136 . All of the shafts  132 - 136  are concentrically aligned. The outer shaft  132  is slidingly disposed over the inner shaft  134 . The inner  134  and outer  132  shafts are selectively adjustable between an expanded and a contracted configuration, and it may be spring loaded so it is biased to the expanded configuration. A stop  138  is attached to the outer surface of the inner shaft  134  such that it passes through a longitudinally extending slot  140  disposed along the outer shaft  132 . The slot  140  and the stop  138  cooperate to regulate the expansion and contraction of the attachment member  130 . 
     Opposing ends of the inner and outer shafts  132 ,  134  include an alignment well  142  corresponding to the cross sectional shape of the expansion shafts  110 ,  112  of the pull bar assembly  100 . If the diameter of the inner shaft  134  is too small to provide an adequate fit with the end cap/grommet  120  of the expansion shafts, the alignment well  142  of the inner shaft can be disposed on an adaptor  144  that is fitted to the end of the inner shaft  134 . A stub shaft  136  is fixedly attached to each of the inner and outer shafts  132 ,  134 . Each stub shaft  136  includes a weakly biased locking protrusion  146 . The bias of the stub shaft protrusion  146  is only strong enough to prevent unintentional disengagement from the expansion shafts  110 ,  112 . Additionally the surface of the protrusion  146  is preferably semispherical thereby providing a smooth surface for engagement with the end cap  120 . The bore  118  of the end cap  120  roughly approximates the diameter of the stub shaft  136 . The weakly biased locking protrusion provides a mild resistance to the insertion of the stub shaft  136  into the bore  118 . Accordingly, the locking protrusion  146  depresses into the stub shaft  136  on insertion and removal of the stub shaft with the bore  118 . In an installed configuration, the stub shafts  136  serves as an axel or pin about which the pull bar assembly  100  pivots. 
     An operator would install the pull bar assembly  100  by compressing the attachment member  130  into its compressed configuration. The inner shaft  134  would slide into the outer shaft  134  until the stop  138  of the inner shaft  134  reaches the end of the slot  140  disposed on the outer shaft  132 . The stub shafts  136  would be aligned with the bore holes  118  of the expansion shafts  110 ,  112 . The compression of the attachment member  130  would allow the stub shafts  136  to enter the bore holes  118 . The pull bar  100  and the attachment member  130  would then be aligned with the corresponding sockets  58  on the elbow joint  56  of the frame  20 . The operator would then fully release the compression of the attachment member  130  allowing it to return to its expanded configuration. 
     In an alternative embodiment of the pull bar assembly  100 , the pull bar assembly  100  includes components and operates similar to as described. In this embodiment, the cross member  106  is made of semi-rigid or semi-resilient materials that allows slight bending of the cross member  106 . The ends of the  110  and  112  expansion shafts each include a protrusion that may be aligned and inserted into the corresponding sockets  58  on the elbow joint  56  of the frame  20 . The protrusions have generally similar diameter as the corresponding socket  58 . Between the protrusions on the pull bar assembly  100 , a stop bar having roughly the same length as the cross member  106  is attached to either the expansion span  110  or  112  via a hinge. The stop bar can be raised and removably fastened onto the expansion span that it attaches to when in raised position by different means that may include a strap or magnetic strips. In operation, the operator compresses the pull bar assembly  100  to attach the pull bar assembly to the frame via the sockets  58  by inserting the protrusions into the sockets  58 . The stop bar is then dropped from the raised position to push the protrusions further into the sockets  58  and keeping the pull bar assembly pivotably attached to the frame. The length of the stop bar should roughly be the length of the cross member  106  minus the diameter of the both expansion spans. 
     The present application may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the application is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.