Abstract:
An improved wheeled luggage case having a pair of freely rotating large wheels that have a diameter substantially greater than the height of the center of gravity of the wheeled luggage case itself (when in an upright, at rest position). The weight of the wheeled luggage case is largely transferred to the large wheel pair when being towed, reducing the load burden on a user and making it easier to pull the wheeled luggage case over long distances, for example, between airport terminals.

Description:
FIELD OF THE INVENTION 
     The present invention generally relates to wheeled luggage, and in particular, to an improved wheeled luggage case. 
     BACKGROUND OF THE INVENTION 
     Luggage today, especially, luggage carried on board mass transport, such as airlines, buses and trains, are provided with features such as straps and/or built-in extension handles and either plastic or metal slider “feet” or miniature wheels. In the prior art, two to four small wheels mounted on the base of the luggage—or even on other surfaces to facilitate moving the luggage when the wheels in the base are not in a correct position to roll on a surface—are provided for rolling, generally without an axle, but the weight in pulling such a load is mostly on a user and not primarily on the wheels since the luggage generally needs to be tilted on two wheels to more readily move it. 
     These features are designed to facilitate sliding or rolling luggage over paved concourses and for general movement within stations and between arrival and departure terminals which may be separated by quite a walking distance. But such features generally do not fully ease the burden of pulling a load across various floor surfaces, both indoor and outdoor and over obstacles such as curbing and stairs encountered in unexpected places. 
     Most mass transportation centers offer assistance to travelers with personal luggage which needs to be moved across large walking distances by providing porter service or large, four-wheeled baggage carts, but aside from the added expense of such a service, it is not always available, either due to lack of baggage carts, especially at peak hours of travel, or because the central collection points for the baggage carts are not conveniently located so as to be immediately useful to a traveler. 
     Another solution is to use a portable, light-weight mini-dolly that folds-up when not in use, but this is an added expense and the folded mini-dolly may be inconvenient to carry when not in use and may be damaged in transit. Furthermore, a mini-dolly is generally not well-suited for pulling fully-loaded and heavy luggage across long distances. Luggage provided with miniature wheels, and mini-dollies in general, are inappropriate for navigating stairs or crossing street curbing when trying to bring luggage as close as possible to a waiting vehicle. Baggage carts are especially not able to traverse stairs to reach another floor of a terminal, and can&#39;t be used without ramps or elevators which are often inconveniently located. 
     In addition, modern travelers, especially businessmen, are likely to have laptops to carry, but having their hands full, may find it awkward to also pull luggage around, with or without the extra concern for managing the use of a baggage cart or mini-dolly. 
     Thus it would be desirable to provide a light-weight, sturdy, improved wheeled luggage case that would be easily movable over a variety of surfaces, including stairs, without the need for baggage carts or mini-dollies, and which has a low center of gravity to ease the burden of moving personal goods, such as clothing and accessories, from place to place while traveling. 
     SUMMARY OF THE INVENTION 
     Accordingly, it is a broad object of the present invention to overcome the above-mentioned disadvantages of the prior art by providing an improved wheeled luggage case having a pair of freely rotating large wheels that have a diameter substantially greater than the height of the center of gravity of the wheeled luggage case itself (when in an upright, at rest position). The weight of the wheeled luggage case is largely transferred to the large wheel pair when being towed, reducing the load burden on a user and making it easier to pull the wheeled luggage case over long distances, for example, between airport terminals. 
     It is another object of the present invention to provide a wheeled luggage case that can easily and efficiently be navigated over stairs and street curbing to move the wheeled luggage case between different levels with a minimum of user effort. 
     It is yet another object of the present invention to provide a wheeled luggage case having a large wheel pair rotatably mounted at the lower portion of a storage chamber integrally formed with a base. The wheeled luggage case can be oriented into an upright, immobilized position resting on the base and a foot member, where the foot member is formed as part of the base extending outward on one side of the wheeled luggage case. The wheeled luggage case can be oriented into a wheeled position by tilting an extendable towing rod fixedly attached to an opposite side of the wheeled luggage case. 
     It is still another object of the present invention to provide a wheeled luggage case with a multi-sectioned cover defining an opening for allowing partial or full access to an interior storage chamber. 
     It is a further object of the present invention to provide a narrow inside pocket formed on an inside surface of a multi-sectioned cover to a wheeled luggage case suitable for accommodating a thin-profile electronic device, such as a laptop computer which is easily accessible to a user, yet secure and out of sight when stored for traveling. 
     Thus there is provided a wheeled luggage case having a towing rod for towing, the wheeled luggage case comprising:
         a storage chamber for holding personal goods, apparel and accessories and provided with a base;   a multi-sectioned cover defining an opening on one side of the storage chamber for providing access thereto;   a pair of freely rotating large wheels mounted on a common axis on each side of a lower portion of the storage chamber and having an inner rim upon which a set of smaller wheels fixedly attached to the storage chamber rotate; and   a foot member fixedly formed on a first edge of the base for immobilizing the wheeled luggage case,
 
such that when the storage chamber is closed with the multi-sectioned cover and the wheeled luggage case is tilted at a forward angle by action of the towing rod, the foot member is lifted away from contact with a floor surface allowing movement of the wheel luggage case, the large wheels bearing most of the weight of the wheeled luggage case, the weight being distributed among the set of smaller wheels, relieving the load stress on a user; and when the storage chamber is tilted into an upright position by action of the towing rod, the foot member on the base maintains the wheeled luggage case in an immobilized rest position.
       

     Although the foot member, acting in concert with the base of the storage chamber of a wheeled luggage case, immobilizes it, it is quite easy to resume movement by simply pulling on a strap or towing rod and/or handle (as are commonly found on luggage cases) attached to the exterior of the storage chamber to tilt it at a slight angle. This raises the foot member and base from contact with a floor or other surface and allows the large wheel pair to contact the floor and to take up the weight of the wheeled luggage case and rotate forward. The large wheel pair, in one embodiment of the present invention, are slightly raised above a floor when the foot member is engaged, and when the foot member is levered upward by tilting the wheeled luggage case, the large wheel pair are again in full rolling contact with the floor. 
     In an alternate embodiment of the present invention, the wheels may also be in contact with a surface simultaneously with the foot member and base to provide additional support to a wheeled luggage case when in an upright, rest position. 
     The luggage is especially sized so as to meet the stringent requirements of under-the-seat storage aboard aircraft, or for storage in overhead compartments. 
     A third small wheel is optionally used to provide further stability when pulling the wheeled luggage case over flat surfaces so as not to burden a user with any weight load of the wheeled luggage case. 
     In a first preferred embodiment of the present invention (see  FIG. 1 ), the storage chamber is provided with reinforced ribbing for added strength enabling sitting on it when put in a prone position. In a low-profile, cylindrical embodiment of the present invention, the storage chamber is sufficiently strong to serve as a sturdy platform on which to sit. In the latter embodiment, the foot member is in contact with the floor to safely immobilize the wheeled luggage case. 
     In a preferred embodiment of the present invention, the large wheel pair are made of rubber/silicone to enable rolling over various grades and conditions of flooring and under adverse conditions, such as rolling over small stones, and over snow-covered, or icy surfaces. 
     Optionally, a battery-operated light is provided within the storage chamber which lights when the cover is opened so as to provide illumination so a traveler can inspect the contents under conditions of poor external lighting and at night. 
     Other features and advantages of the present invention will become apparent from the drawings and the description given below. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a better understanding of the present invention with regard to the embodiments thereof, reference is made to the accompanying drawings, not to scale, in which like numerals designate corresponding elements or sections throughout, and in which: 
         FIGS. 1A-D  are side views of a wheeled luggage case constructed in accordance with a preferred embodiment of the present invention; 
         FIGS. 2A and 2B  illustrate the high center-of-gravity of a large wheel-pair of another embodiment of the present invention; 
         FIGS. 3A-C  show side and three-quarter views to illustrate three stages in the opening of the multi-sectioned cover of the wheeled luggage case of  FIG. 1 ; 
         FIGS. 4A-C  are views illustrating the disposition and exemplar use of an inside pocket formed within the storage chamber of the wheeled luggage case of  FIG. 1 ; and 
         FIGS. 5A and 5B  are enlarged, detailed views of the large wheel pair of  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       FIGS. 1A-D  are side views of a wheeled luggage case constructed in accordance with a preferred embodiment of the present invention. 
     Referring now to  FIG. 1A , wheeled luggage case  10  is shown in an upright, rest mode and comprises a storage chamber  12  having a multi-sectioned cover  14  secured by standard quick-release fasteners, such as a clasp  46 , and a base  16  advantageously formed with a foot member  18  for immobilizing wheeled luggage case  10 . The wheeled luggage case  10  is provided with a pair of large wheels  20  (shown as a single wheel in a side view) which are rotatably mounted directly to opposite sides of a lower portion of storage chamber  12  (see also  FIG. 3 ) and provided with a closed, wheel cover  21 . 
     In  FIG. 1A , one preferred method of resting wheeled luggage case  10  in an upright position is to use both base  16  disposed at right angles to the sides of storage chamber  12  and the large wheel pair  20  to support the weight of wheeled luggage case  10  on flat surface  28 , but in another preferred embodiment of the present invention, the large wheel pair  20  is raised slightly off the surface  28  so as not to be in rolling contact with it when the foot member and base are in contact with surface  28  (see  FIG. 5 ). Alternatively, the large wheel pair  20 , as well as at least one optional small wheel (not shown) may bear some of the weight of the wheeled luggage case  10  with the base  16  and foot member. Additionally, or alternatively, a small, foot stop (not shown) extending downward from base  16  may be used in combination with large wheel pair  20  to immobilize wheeled luggage case  10  when in an upright, rest position. 
     Foot member  18  is formed as an integral extension of base  16 , extending outward on one side of wheeled luggage case  10  to help maintain the luggage case  10  in an upright position. Towing rod  24  and handle  26  are provided to manipulate wheeled luggage case  10 . 
     The inventive wheeled luggage case  10  may be modified by the addition of a small wheel (not shown) to allow towing the wheeled luggage case in the upright position by using a strap or cable (not shown). The cable (not shown) is optionally provided and can be pulled out from handle  26  for towing wheeled luggage case  10 , and retracted by use of a rewind spool and spring mechanism (not shown). 
     As shown in  FIG. 1B , towing rod  24  needs to be only slightly tilted downward (curved arrow) in order for the foot member  18  and base  16  to tilt upward (curved arrow) away from a floor surface  28  at an equal and opposite angle, enabling wheeled luggage case  10  to be moved freely and easily on the large wheel pair  20  which now comes into rolling contact with surface  28 . 
     Referring to  FIGS. 1C-D , the large size of the wheel pair  20  in respect to storage chamber  12 , in general allows wheeled luggage case  10  to efficiently and comfortably navigate stairs and curbing on streets—obstacles frequently encountered by travelers with wheeled luggage. The large wheel pair  20  is about ⅓ the height of storage chamber  12  in the embodiment of the present invention shown in  FIG. 1 . The large wheel pair  20  provides a good attack angle in approaching the risers  30  of standard construction stairs (or street curbing), which usually are between 15 and 20 cm. in height, and assist in easily raising the wheeled luggage case to a higher level. 
     The large wheel pair  20  raises the tipping angle of the wheeled luggage case  10  itself to almost half the height of the large wheel pair  20  (practically to their center). Thus, when tilted, a large portion of the weight load of the wheeled luggage case  10  is transferred to the large wheel pair  20  so as to divide the weight of the wheeled luggage case  10  into two portions: one above and one below a line  32  representing the central axis and center-of-gravity of large wheel pair  20  (see  FIGS. 2A-C ). The weight in each portion balances the weight in the other causing a greater portion of the total weight that was until now borne by a user of wheeled luggage case  10  to be transferred to the large wheel pair  20 , in accordance with the principles of the present invention. 
       FIGS. 2A and 2B  illustrate another embodiment of the present invention featuring the high center-of-gravity of a large wheel-pair of wheeled luggage case  44 . A dashed line  32  is shown representing the raised center of gravity of wheeled luggage case  44 , and corresponds to the height from a surface  28  of the central axis of the large wheel pair  20  (seen as a single wheel in a side view). The wheeled luggage case  44  comprises a cylindrical storage chamber  34  substantially having the same profile as the large wheel pair  20 . Only a small, standard carrying handle  36  is visible above the height of the large wheel pair  20 . The cylindrical shape is of a convenient size for carrying on-board airlines and can be stowed as are other commonly used travel bags in low-profile storage areas, such as under seats. 
     The wheeled luggage case  44  is provided with a standard, extendable towing rod  38  and handle  40 , and also has a unique foot member  42  for immobilizing the wheeled luggage case  44  when in a rest mode as shown in  FIG. 2A , in accordance with the principles of the present invention. 
       FIG. 2B  illustrates the towing mode of the wheeled luggage case  44  which is pulled at a forward tilting angle (curved arrow) over surface  28 . The center-of-gravity (represented by line  32 ) lies at the central axis of the large wheel pair  20  so as to minimize the weight load on a user while pulling on towing rod  38 . The immobilizing foot member  42  is raised from surface  28  (curved arrow) to allow wheel pair  20  to move forward. 
       FIGS. 3A-C  show three pairs of side and three-quarter views to illustrate the three stages in the opening of the multi-sectioned cover of the wheeled luggage case of  FIG. 1 : fully closed ( FIG. 3A ), partially opened ( FIG. 3B ), and fully opened ( FIG. 3C ), respectively. 
     FIGS.  3 A 1 -A 2  is a side view and a three-quarter view, respectively, of the wheeled luggage case  10  from  FIG. 1  shown in a rest mode. Multi-sectioned cover  14  is shown closed and latched with standard latching devices, such as clasps  46 , as are known to those skilled in the art. The latching devices  46  may also be provided with key locks (not shown) or other security devices in a manner as is understood by those skilled in the art. 
     FIGS.  3 B 1 -B 2  is a side view and a three-quarter view, respectively, of the wheeled luggage case of  FIG. 1  showing only a top section  48  of the multi-sectioned cover  14  opened to conveniently access both the contents of the top portion of the storage chamber  12  and an inside pocket  50  formed within storage chamber  12  on an inner surface of multi-sectioned cover  14 . The inside pocket  50  is useful for accommodating any flat-shaped object, but in the example shown, is preferably designed to hold a laptop computer or other electronic device (see  FIG. 4 ). 
     FIGS.  3 C 1 - 2  is a side view and a three-quarter view, respectively, of the wheeled luggage case  10  from  FIG. 1  shown in a rest mode with the multi-sectioned cover  14  in the process of being fully opened to access all the contents of storage chamber  12 . The multi-sectioned cover  14  is hinged so as to be fully openable when the wheeled luggage case  10  is in an upright, rest mode as shown, but it may be opened whenever multi-sectioned cover  14  is exposed, such as when placed in a horizontal position on a surface with the multi-sectioned cover  14  facing up. One surface of storage chamber  12  is provided with ribbing  58  to provide added strength for sitting on the prone wheeled luggage case  10 . Note that multi-sectioned cover  14  is fixedly hinged to the base  16  at the juncture of foot member  18 . 
       FIGS. 4A-C  show views illustrating the disposition and exemplar use of an inside pocket formed within the storage chamber of the wheeled luggage case of  FIG. 1 . The inside pocket  50  provides a convenient space for storing a thin object, such as a laptop computer  52 . Other stored goods within storage chamber  12  are removable or insertable by fully opening the multi-sectioned cover  14  (as shown in  FIG. 4C ). 
     Wheeled luggage case  10  is provided with ribbing  58  integrally formed in the surface of storage chamber  12  both for design purposes, and for structural strength when laying the wheeled luggage case  10  to rest on its side with the outside surface of towing rod compartment  56  and ribbing  58  maintaining contact with a flat surface to allow a user to use the opposite side provided with the multi-sectioned cover  14  as a convenient place to sit. For this purpose, multi-sectioned cover  14 , inside pocket  50 , and storage chamber  12  as a whole are made of sturdy, lightweight material, such as rubber or molded plastic in a preferred embodiment of the present invention, although other suitable materials may also be used. 
       FIGS. 4A-B  are three-quarter and side views, respectively, of wheeled luggage case  10  with multi-sectioned cover  14  shown partially opened so that a top section  48  allows access to an inside pocket  50 . By way of example, a laptop  52  is shown being inserted into or removed from inside pocket  50  and is safely hidden from sight within inside pocket  50  when top section  48  of cover  14  is closed. 
       FIG. 4B  shows a side view of the inside pocket  50  in an accessible position with the top section  48  opened and laptop  52  withdrawn. The multi-section construction enables partial opening to efficiently and conveniently access storage chamber  12 , for example, to remove or insert a laptop computer  52  without disturbing other packed content. In a preferred embodiment of the present invention, multi-sectioned cover  14  is made from two parts, the top section  48  serving as a convenient, independent access to inside pocket  50  and to whatever contents lie at the top of storage chamber  12 . 
       FIG. 4C  shows a three-quarter view of wheeled luggage case  10  with cover  14  in the process of being fully opened so that access is had to all of the contents of storage chamber  12  and also to inside pocket  50 . Notice that a fastener device, such as a quick-release latch  46  is also provided for the top section  48  to secure it in place and preferably, lock it. 
     The towing rod  24  with handle  26  are conveniently retracted when not in use into a towing rod pocket  56  formed integrally with storage chamber  12  and which form a balanced configuration with ribbing  58  for resting wheeled luggage case  10  in a prone position suitable to use as a platform for sitting. 
       FIGS. 5A and 5B  are enlarged, detailed views of the large wheel pair of  FIG. 1 . In a preferred embodiment of the present invention, a set of four smaller wheels  22  are fixedly attached to the lower outside portion of storage chamber  12  and rotate along the inner rim  60  of each of the large wheel pair  20  similar to large roller bearings. The set of four smaller wheels  22  do not have a central rotational axis, but help distribute the load on each of the ring-type wheels of the large wheel pair  20 . 
     Optionally, three smaller wheels disposed in a triangular configuration may be used in place of the set of four smaller wheels  22 , or, depending on the space available and the overall physical dimensions of the large wheel pair  20 , five or more smaller wheels may also be employed as may now suggest themselves to those skilled in the art. 
     In a preferred embodiment of the present invention, large wheel pair  20  rotates freely on a common axis, but without the need for a central axle since it rotates with the set of four smaller wheels  22 . The absence of an axle advantageously simplifies manufacture, conveniently reduces the cost and the weight of the finished product, and avoids displacing valuable space within storage chamber  12  ordinarily used for accommodating an axle and supporting structure. 
     Nevertheless, in another embodiment of the present invention, such as with larger and heavier luggage cases (not shown), a central axle may alternatively and optionally be provided without detracting from the principles of the present invention. When, for example, a central axle is located at a point above or near the center-of-gravity of wheeled luggage case  10 , the effect would be similar to that of the axle-less large wheel pair  20  of the present invention, relieving a user of much of the weight of the load when towing heavier luggage, and transferring it to the wheels 
     The large wheel pair  20  is made of rubber/silicone which allows comfortable and efficient travel over many kinds of surfaces and under adverse conditions, such as rolling over small stones, snow, ice, and slippery ceramic flooring even though the large wheel pair may not be especially made for this. 
     Having described the invention with regard to certain specific embodiments, it is to be understood that the description is not meant as a limitation, since further modifications may now suggest themselves to those skilled in the art, and it is intended to cover such modifications as fall within the scope of the described invention.