Patent Publication Number: US-6220411-B1

Title: Expandable luggage

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to luggage, especially travel luggage, and in particular to luggage that can be expanded when desired. 
     The needs of travelers for luggage space can vary considerably, depending on the duration of a trip, the nature of the trip in terms of the types of clothing and other gear required, and the climate of the destination. For example, regardless of the purpose and the climate, a traveler does not need as much luggage space for a trip of short duration as for a long one. Generally, a business traveler does not need as much luggage space as a recreational traveler, especially one who needs both casual and dress clothes. In most cases, men need less luggage space than women. 
     One way for travelers to provide for both smaller and larger luggage space requirements is to have a moderately sized suitcase for some trips and a large one for other trips. Another way is to have two moderate sized suitcases and use only one when possible and use both when a larger capacity is needed. There have also been various proposals for expandable luggage. An expandable item of luggage offers the traveler a possible savings in cost as compared to the costs of purchasing more than one piece of luggage. Moreover, the capability of expanding a piece of luggage permits a traveler to change the carrying capacity in the course of a trip. Not infrequently, a traveler will make purchases on a trip and will need more room for the return trip than for travel to a destination. 
     Most previously known luggage having a variable volume is of the “soft” type, such as a duffle bag with expandable sections that can be collapsed and secured to a main section. The expandable “hard” luggage that is currently available lacks rigidity when expanded due to inadequate linking of separate rigid frame components that move away from each other when the luggage is expanded. 
     BRIEF SUMMARY OF THE INVENTION 
     An object of the present invention is to provide an item of expandable luggage of the “hard” type that has a high degree of geometric stability when expanded. It is, in particular, an objective of the invention to provide a highly effective coupling between two frame components that move apart when the luggage item is expanded so that relative movements of the two frame components are minimized. A further object is to provide a hard expandable luggage item that is easily changed between a smaller volume and a larger volume. 
     The foregoing objects are attained, in accordance with the present invention, by an item of expandable luggage that includes a frame having a first substantially rigid component and a second substantially rigid component, each of which includes a pair of opposite rectangular planar wall panels and which together with a pair of wall members form the peripheral boundary of a variable volume receptacle and a rectangular area. A peripherally continuous gusset of flexible material is connected between the wall panels and wall members of the two frame components and provides, when the luggage item is expanded, a portion of the peripheral wall of the receptacle. A bridge assembly joins each wall panel of the first component to a corresponding wall panel of the second component in coplanar relation and for linear displacement of the two components toward and away from each other. Each bridge assembly includes a pair of parallel spaced-apart slide rails affixed to the wall panel of the first component, a substantially rigid bridge plate affixed to the wall panel of the second component and slidably received by the slide rails, and a releasable latch that couples the bridge plate to the wall panel of the first component in at least one position in which the second component is held securely in a position spaced apart from the first component. 
     The bridge plate/slide rail arrangement provides high rigidity to the luggage item in the expanded state. Forces tending to displace the frame components in the planes of each of the bridge plates and the wall panels with which the bridge plates are associated are transmitted from the second frame component to the bridge plate and from the bridge plate through the slides to the first component. The spacing of the slide rails and the corresponding length of the bridge plate between the slide rails provide considerable strength and stiffness that resists relative displacements of the components and maintains both the coplanar relationships of all of the peripheral wall panels and a parallel relationship between the two frame components. The bridge plate/slide rail arrangement, in other words, maintains stability of the frame system in both the collapsed and expanded states against displacement in mutually perpendicular directions in a plane perpendicular to the planes of the peripheral walls of the frame components, against skewing of one component relative to the other about any axis perpendicular to that plane, and tilting of one component relative to the other about any line in that plane. The latch holds the two frame components rigidly at the predetermined spacing in the expanded state so that the luggage item cannot collapse under loads imposed on it. 
     Various latches are possible. For example, the latch may permit the bridge plate to be latched to the wall panel of the first component in a plurality of positions, and even in an infinite number of positions. Infinite latch positions are provided in a simple and effective way by a panel of loop material affixed to the bridge panel, a flexible band attached to the wall panel of the first component, and a strip of hook material affixed to the flexible band and releasably engageable with the loop material on the bridge plate. 
     Other forms of latches may include one based on a cam cutout in the bridge plate and a cam disc carried for rotation by the wall panel of the first component and one composed of a resiliently biased catch button carried by the wall panel of the first component and an abutment edge on the bridge plate engageable by the catch button. 
     In a desirable configuration, each slide rail includes a body portion engaging the wall panel of the first component and a projecting flange portion defining with the wall panel of the first component a guide groove. The bridge panel in that configuration resides in engagement with the wall panel with which it is associated and gains stiffness from such engagement—the co-engaging portions of the bridge plate and the wall panel are linked along the slide rails and provide a stiff “unit” that resists bending perpendicular to the plane of the wall panel. Similarly, the bridge plate is fastened to the wall panel of the second frame component and gains support and stiffness from such attachment, again enhancing the rigidity of the bridge assembly. 
     It is desirable for the flange portion of each slide rail to have a guide rib projecting toward the wall panel of the first component. In that case, the bridge plate has along opposite edges a guide groove receiving the guide rib on the flange portion of the slide rail. The rib and groove guiding relationship stiffens both the slide rail and the edges of the bridge plate. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     For a more complete understanding of the present invention, and the advantages thereof, reference may be made to the following written description of an exemplary embodiment, taken in conjunction with the accompanying drawings. 
     FIG. 1 is a generally schematic three-quarter front pictorial view of the embodiment, with portions broken away; 
     FIG. 2 is a front elevational view of a slide rail; 
     FIG. 3 is a side elevational view of the slide rail; 
     FIG. 4 is a rear elevational view of the slide rail; 
     FIG. 5 is an end elevational view of the slide rail; 
     FIG. 6 is an end cross-sectional view of the slide rail taken along the lines  6 — 6  of FIG. 4; 
     FIG. 7 is a front elevational view of a bridge plate; 
     FIG. 8 is a rear elevational view of the bridge plate; 
     FIG. 9 is a view of the top edge of the bridge plate; 
     FIG. 10 is a cross-sectional view of the bridge plate taken along the lines  10 — 10  of FIG. 8; 
     FIG. 11 is a cross-sectional view of the bridge plate taken along the lines  11 — 11  of FIG. 8; 
     FIG. 12 is a front elevational view of the bridge plate and slide rails assembled; 
     FIG. 13 is a cross-sectional view of the assembled bridge plate and slide rail taken along the lines  13 — 13  of FIG. 12; 
     FIG. 14 is a generally schematic view of a side edge of a bridge assembly and latch having the slide rails and bridge plate of FIGS. 2 to  13 , showing the assembly in the retracted position of the luggage item; 
     FIG. 15 is a generally schematic view of a side edge of a bridge assembly and latch having the slide rails and bridge plate of FIGS. 2 to  13 , showing the assembly in the expanded position of the luggage item; 
     FIG. 16 is a front plan view of another bridge assembly useful for the present invention, showing the assembly in the retracted position of the luggage item; 
     FIG. 17 is a view of the top edge of the bridge assembly of FIG. 16; 
     FIG. 18 is a front plan view of the bridge assembly of FIGS. 16 and 17, showing it in the expanded state; 
     FIG. 19 is a front plan view of yet another bridge assembly useful for the present invention, showing the assembly in the retracted position of the luggage item; and 
     FIG. 20 is a front plan view of the bridge assembly of FIG. 19, showing it in the expanded state. 
    
    
     DESCRIPTION OF THE EMBODIMENT 
     The embodiment shown in FIG. 1 has a two-component frame, which may be of any suitable specific construction in terms of materials, manner of assembly, and configurations of the parts. A main frame component  10  has a pair of rectangular planar side wall panels  12  and  14 , a bottom wall member  16  and a top wall member  18 , which are substantially rigid and rigidly connected at the corners. Although the drawing shows the bottom and top members as panels, most travel luggage being marketed currently is of the towable, wheeled type. In practice for such luggage items, the bottom member and top member of the main frame are configured to accept wheels, a towing handle, a carrying handle, and the like. The main frame component  10  may also have a partial or complete rigid back wall panel. A secondary frame component  20  is formed of opposite rectangular planar panels  22  and  24  and top and bottom members  26  and  28 , which as a practical matter will usually also be rectangular planar panels of sheet material. 
     The main frame component  10  receives a cover  30  of a durable fabric. The sides, top and bottom of the secondary frame receive a fabric cover  32 . Access to the interior of the luggage item is through a front opening that is closed by a panel  34 , is joined to the cover  32  at the bottom edge and can be opened and closed by undoing and doing up a zipper  36  along three sides. 
     The main part (main frame  10  and its cover  30 ) of the luggage item is joined to the secondary part (secondary frame  20  and its cover  32 ,  34 ) by a gusset  36  of a durable, flexible material that extends along the entire perimeter of the luggage item (along the top, bottom and both side walls). In the expanded state of the item, the gusset  36  peripherally bounds that part of the entire volume of the main compartment by which the volume of the item is increased upon movement of the secondary unit away from the main unit. In the retracted (smaller volume) state (not shown) of the luggage item, a zipper  40  that extends about the entire perimeter of the item is done up. The gusset  36  folds into the interior of the item. 
     The main frame component  10  is joined to the secondary frame component  20  by two identical bridge assemblies  50 , one of which is associated with the side panels  12  and  22  and the other with the side panels  14  and  24 . Each assembly consists of a pair of parallel spaced-apart slide rails  52  that are affixed to the wall panel  12 ,  14  of the main frame component  10 , a substantially rigid bridge plate  54  that is affixed to the wall panel  22 ,  24  of the secondary frame component  20  and is slidably received by the slide rails  52 , and a latch  56  (shown schematically as an arrow in FIG. 1) that releasably connects the bridge plate  54  to the wall panel  12 ,  14  of the main frame component  10  in at least one position in which the secondary frame component  20  is held spaced apart from the main frame component  10 , thereby to retain the luggage item in the expanded state. 
     A suitable slide rail  52 , as shown in FIGS. 2 to  6 , is injection molded from a durable polymeric material and has a body portion  52   a  with countersunk holes  52   b  for screws or rivets by which it is fastened to the wall panel  12 ,  14  and a flange portion  52   c  with a rib  52   d.  The underside of the body portion  52   a  bears against the surface of the panel  12 ,  14  (or a fabric liner within the luggage item). The flange portion  52   c  forms with the wall panel  12 ,  14  a guide groove that accepts the edge of the panel in sliding/guiding relation. 
     A suitable bridge panel  54 , as shown in FIGS. 7 to  11 , is injection molded from a durable polymeric material and has a recess  54   a  on the side facing into the interior of the luggage item, a slot  54   b  adjacent one edge, holes  54   c  for screws or rivets by which it is fastened to the wall panels  22 ,  24  of the secondary frame component  20 , and edge flanges  54   d  with ribs  54   e  along each side edge. The bottom edge  54   f  is smoothly rounded. Rows of tiny fabric anchor pins  54   g  protrude from the back surface near the upper edge. The guiding/sliding relationship between the slide rails  52  and bridge plate is shown in FIGS. 12 and 13. 
     Many forms of latch can be used to releasably connect the bridge plate to the main frame wall panels  12 ,  14  in the expanded state of the luggage item. The bridge plate  54  of FIGS. 7 to  11  is designed for the latch  56  shown in FIGS. 14 and 15, the showing being schematic for greater clarity. A piece  56   a  of a loop material, such as “VELMAT,” is hemmed along one end to form a bead  45   b,  inserted through the slot  54   b  in the bridge panel  54 , trained along the front of the bridge panel and folded over the top of the bridge panel. When the bridge panel  54  is fastened to the wall panel  22 ,  24 , the loop piece  54   a  is clamped in place; the hem/bead holds the lower edge, and the clamping, along with the tiny pins  54   g,  holds the upper edge. The loop piece  56   a  is received in the recess  54   a  of the bridge panel  54 . 
     A piece  56   c  of smooth strong flexible material is suitably fastened to the main wall panel  12 ,  14  near the edge closer to the secondary wall panel  22 ,  24 , turned around the rounded bottom edge  54   f  of the bridge panel and guided freely along the front face of the bridge panel. A strip  56   d  of hook cloth stitched to the free end of the piece  56   c  is releasably anchored to the loop piece  56   a  at any desired location by the mutual tenacity of the loop and hook materials. The user may easily and quickly adjust the luggage item to any of an infinite number of volumes within the range of the smallest volume with the zipper  40  done up to the largest with the zipper  40  undone and the gusset  36  fully extended by grasping the ends of the pieces  56   c  of both bridge assemblies  50  and pulling them toward the open front of the item. Pulling on the pieces  56   c  draws the pieces  56   c  around the lower edge  54   f  of the bride panel  54  and moves the secondary frame  20  away from the main frame. At any desired point of movement, the user may anchor the hook strips  56   d  to the loop piece  56   a,  thereby setting the volume of the luggage item to the directed size. 
     In all positions of the latch assembly, and especially at the largest volume, the bridge assembly stabilizes the shape of the luggage item by preventing up and down movements, side to side movements, rotational skewing movements, and side to side and front to back cocking movements of the secondary unit relative to the main unit. More simply put, the sliding support of the bridge plate  54  by the slide rails  52  holds the secondary unit stationary laterally, longitudinally and rotationally relative to the main unit in the plane of the rear edge of the secondary frame and maintains the plane of the rear edge of the secondary unit parallel to the plane of the front edge of the main unit. The latch  56  keeps the luggage item from collapsing. If the luggage item is adjusted to less than the maximum volume, the latch does not preclude movement of the secondary unit to the maximum volume position. Such movement is not of concern. The purpose of the latch is to maintain a desired minimum volume in an expanded state for the convenience of the user when he or she is packing the luggage and to avoid crushing the contents when the luggage is handled or stowed for transport. 
     Another bridge assembly  150 , as shown in FIGS. 16 to  18 , has a slightly modified bridge plate  154  and a push-button catch unit  156 . The bridge plate  154  has a recess (not shown per se but apparent from the front as a protuberance  154   a ) in the rear surface that accepts the catch unit  156  in the retracted state (FIG.  16 ). A push button  156   a  of the catch unit is resiliently biased relative to the casing  156   b  of the catch unit such that in the expanded state of the luggage item it engages a rounded edge  154   b  of the bridge panel at the lower edge of the recess/protuberance  156   a,  thus latching the luggage item in the expanded state (FIG.  18 ). The front face of the push button is tapered so that when the user pulls the secondary unit away from the main unit from the retracted position, the lower edge of a hole  154   c  in the recess/protuberance  154   a  cams the push button against its resiliency, so the user does not have to push the push buttons to expand the luggage item. Pushing in on the release button  156   a  disengages the button from the shoulder  154   b,  allowing the luggage item to be restored from the expanded state (FIG. 18) to the retracted state (FIG.  16 ). 
     A bridge assembly  250  that is based on a cam latch, as shown in FIGS. 19 and 20, includes a modified bridge plate  254 , which has a cam hole  254   a,  and a cam disc  256 , which is pivotally attached by a screw  256   a  (or rivet) to the main frame wall panel  12 ,  14  and overlies the bridge plate  254 . An arcuate cam follower rib  256   b  that protrudes from the back face of the cam disc  256  pushes the bridge plate  254  from the retracted state (FIG. 19) to the expanded state (FIG. 20) when a user manually rotates the cam disc  256  clockwise about the pivot screw  256   a.  A rib  256   c  on the front face of the cam disc  256  can be engaged by the user&#39;s fingers to facilitate rotating the cam disc. A ridge  254   b  in the cam hole  254   a  captures the cam follower rib  256   b  when the luggage item is in the expanded state. Attaining the expanded state requires a slight movement of the secondary unit to a position farther away from the main unit than the final expanded position.