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FIELD OF THE INVENTION  
         [0001]    The present invention relates to vertical conveyor devices. More specifically, the invention relates to a vertical conveyor device that can accommodate motor vehicles of varying height.  
         BACKGROUND OF THE INVENTION  
         [0002]    Urban congestion demands efficient land use.  
           [0003]    Vertical storage devices for stacking and storing vehicles are known. Known systems include a series of platforms or containers that move in a circuit around an endless-loop type drive, or carousel. A location on the circuit serves as an access point. When a container reaches the access point, a vehicle can be either placed or removed from the platform of the container. Then the container moves away and another platform may be accessed via the access point.  
           [0004]    Previous patents disclose vertical storage devices for motor vehicles.  
           [0005]    Lichti U.S. Pat. No. 5,374,149 discloses a vertical conveyor for storing and conveying automobiles. Here, an endless chain in the shape of a race track is mounted and a plurality of platforms holding automobiles is connected and move about this race track frame. Lichti continues to refine that conveyor system in U.S. Pat. No. 5,425,442. The latter patent is a continuation of the former patent.  
           [0006]    Vita U.S. Pat. No. 5,980,185 discloses a vertical vehicle parking structure containing a means for coordinating the operation of the tower lift.  
           [0007]    Zhang et al. U.S. Pat. No. 5,810,539 discloses a “maximum auto parking device.” This patent claims a stopping hole on a car pan to position a vehicle. This reference also teaches strengthening rods for the car pans, a position for a parking power control box, and the use of balance weights to assist in moving a carousel.  
           [0008]    The height of passenger vehicles traditionally has been in a narrow range. Today, however, sport utility vehicles (SUV&#39;s) have come into fashion. Consequently, contemporary passenger vehicle heights vary greatly. For example, the year 2000 model Porsche 911 has a height of 51.4 inches, while the year 2000 model Range Rover has a height of 71.6 inches.  
           [0009]    Presently, vertical conveyor systems either accept exclusively compact cars, thereby excluding SUV&#39;s, or accommodate most vehicle heights, thereby wasting precious space.  
         SUMMARY OF THE INVENTION  
         [0010]    It is an object of the present invention to provide a vertical storage device to accommodate vehicles of varying sizes, by providing various sized storage containers with an adaptable means of vehicle access.  
           [0011]    It is a further object of the present invention to provide a walkway that can accommodate storage containers having platforms at varying heights, thereby providing safe access to the containers. The movable walkway allows free rotation of the platforms, and access by physically impaired patrons.  
           [0012]    Another object of the present invention is to provide an improved pan that self-bails accumulated rainwater and vehicle fluids.  
           [0013]    It is yet another object of the present invention to provide a lateral tire guidance system, thereby assuring proper location of vehicles upon the platforms.  
           [0014]    The present invention relates to a vertical vehicle storage device that efficiently accommodates motor vehicles of varied height. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0015]    Other objects and further features of the advantageous vertical conveyor device of the present invention are illustrated by the accompanying drawings wherein:  
         [0016]    [0016]FIG. 1 illustrated is a perspective view of a system in accordance with the invention;  
         [0017]    [0017]FIG. 2 is a view illustrating the access problem created by placing different sized containers around a vertical storage carousel;  
         [0018]    [0018]FIG. 3 a  is a perspective view of a ramp-lifting assembly, with the ramp omitted;  
         [0019]    [0019]FIG. 3 b  is a cross-sectional view of a ramp-lifting assembly;  
         [0020]    [0020]FIG. 4 a  is a perspective view of a walkway-lifting assembly, with the walkway omitted;  
         [0021]    [0021]FIG. 4 b  is a cross-sectional view of a walkway-lifting assembly.  
         [0022]    [0022]FIG. 5 is a view of a platform curving upward in a fore/aft direction.  
     
    
     DETAILED DESCRIPTION  
       [0023]    [0023]FIG. 1 illustrates a vertical conveyor system  10  for conveying containers of various sizes, and for solving the problem created by placing various sized containers  24  around a vertical storage carousel  22 .  
         [0024]    [0024]FIG. 2 illustrates the problem created by the use of different sized containers. The distance  6  between the end of the carousel conveyor  30  and the floor  32  of the garage remains the same despite the size of the container.  
         [0025]    Therefore, tall containers  28  are flush with the floor  32 , and an SUV has no problem accessing the pan of the tall container. However, when the carousel rotates and a short container  26  is presented for a shorter car, the pan of the short container  26  is suspended above the surface of the floor  32 . To access the pan  16  (see FIG. 1), the present invention offers a ramp  12 . Similarly, an elevated container presents a problem for passengers laterally accessing the pan. Hence, the present invention provides an analogous manner of access, a walkway  14 . The walkway  14  allows passengers and drivers to step into their vehicles. The walkway  14  also provides the advantage of access for the handicapped and, thus, is helpful even accessing a tall container.  
         [0026]    Installation of a ramp-lifting assembly  34 , shown in FIGS. 3 a  and  3   b , and a walkway-lifting assembly, shown in FIGS. 4 a  and  4   b , requires placement of a pit  20  (see FIG. 1) below the containers  24 . The dimensions of the pit are slightly larger than the dimensions of the pan  16 .  
         [0027]    The ramp-lifting assembly  34  includes a ramp  12 , running the width of the pit  24 . A ramp bracket  36  pivotally joins the ramp  12  to the top edge  38  of the ramp side wall, where the top edge meets the floor of the garage.  
         [0028]    A carriage  40  is located inside the pit and is movably attached, in parallel, to the ramp side wall  42 . A carriage ramp link  44  joins the carriage and the ramp. A first bracket  44  and second bracket  46  are used for attachment of the link. The first bracket  44  pivotally joins the carriage ramp link  44  to the ramp, and the second bracket  46  pivotally joins the carriage ramp link to the carriage.  
         [0029]    A moving means for raising and lowering the ramp is located on the carriage  40 . This means may be hydraulic or motorized. For illustrative purposes, here a motor  48  is used. The motor  48  is mounted in the approximate center of the carriage  40 , and a speed reducer  50  is attached to the motor  48 . A drive shaft  52  is attached to the speed reducer  50 . The motor  48  translates motion through the speed reducer  50 , thereby moving the drive shaft  52 . Another moving means might allow direct attachment to the drive shaft.  
         [0030]    The drive shaft  52  runs approximately the length of the carriage  40 , and is mounted to the carriage  40  at both ends of the drive shaft  52  by first and second drive shaft brackets  54 ,  56 , respectively. These brackets  54 ,  56  aid in holding the drive shaft  52  onto the carriage  40 . The drive shaft  52  rotates freely within the first and second drive shaft brackets  54 ,  56 . First and second ramp cams  58 ,  60  are attached to opposite ends of the drive shaft  52 . Mounted to the walkway side wall are first and second roller plates  62 ,  64 . The roller plates  62 ,  64  include a roller  66  and a plate  68 . The plate  68  mounts the roller plate  62 ,  64  to the wall, and the roller  66  rolls over the ramp cams  58 ,  60 . A vertical conveyor system may have a single ramp where a vehicle enters and exits, or the system may have a ramp-lifting assembly at both ends, thereby allowing access through either end.  
         [0031]    The vertical conveyor system also has a walkway-lifting assembly  70 , shown in FIGS. 4 a  and  4   b . The walkway-lifting assembly  70  serves a similar function as the ramp-lifting assembly  34  discussed above. However, the mechanics of the walkway-lifting assembly  70  differ from that of the ramp-lifting assembly  34 . The walkway-lifting assembly  70  includes a walkway  14 . The walkway  14  runs the entire length of the pit  20  (see FIG. 1). The walkway  14  is pivotally joined to the top edge  72  of the walkway side wall by a walkway bracket  74 . A walkway roller  76  contacts the underside of the walkway. A walkway rod  78  is attached to the walkway roller  76  and the other end of the walkway rod is connected to a rod cam  80 . The rod cam  80  contacts a walkway cam  82 . The walkway cam  82  is attached to the drive shaft  52  on the ramp-lifting assembly  34 . The carriage  40  is capable of lifting both a walkway  14  and a ramp  12 , and the two structures are synchronously positioned.  
         [0032]    The containers  24  positioned around the carousel  22  of the vertical conveyor system  10  include pans  16 , which are suspended by supports  18  (see FIG. 1). In the case of short containers, the supports are short. Likewise, tall containers have long supports. In a preferred embodiment, the ratio of short containers to tall containers will be equal, alternating short/tall around the carousel.  
         [0033]    Another element of the present invention is a pit. A pit accommodates the mechanics of the walkway and ramp. Moreover, the pit makes possible additional enhancements to the vertical conveyor system.  
         [0034]    [0034]FIG. 5 shows a pan  16  which assumes either an unloaded position  86 , or a deflected position  84 . The pan  16  is arched when no load rests upon it, and flattened when loaded with a vehicle.  
         [0035]    The platform  16  is configured to maintain control of any fluids that may leak from the vehicles that the platform supports. These fluids may be water (melting snow or ice), antifreeze, oil, gasoline, transmission fluid, brake fluid, etc. As the fluids may be explosive, they must not be captured or contained in a confined volume; rather the fluids should be kept in the open.  
         [0036]    The platform  16  is provided around its periphery with a continuous rim  88  to hold the fluids. This rim  88  has been designed to be compliant with the American Disabilities Act, enabling unimpeded use of the platform by handicapped in wheelchairs. In a preferred embodiment, the height and floor area of the rim are such that a flat and horizontal platform can hold approximately forty-six gallons of fluids; when the platform is tilted one inch from level side to side the liquid capacity becomes thirty gallons.  
         [0037]    During operation, the platform must be able to support vehicles that weigh up to 5,500 lbs; the average vehicle is estimated to weigh approximately 4,000-4,500 lbs. Actual load/deflection tests indicate that the platform will deflect one inch downward in the center under the weight of an average vehicle.  
         [0038]    The shape of the platform when deformed results in a fluid holding capacity significantly reduced from the holding capacity when the platform is flat.  
         [0039]    It is common practice to camber a structure so that, when loaded, it essentially lies flat. By manufacturing the platform in a circular upward shape, with an upward central rise of one inch, one forms a platform that will become basically flat when loaded with an average 4,000 lb vehicle. Thus, when the average vehicle is in place on the platform, it can hold thirty to forty-six gallons of fluid.  
         [0040]    When being accessed, the platform  16  is positioned at bottom, dead center of the carousel  22 . The platform  16  is positioned above the pit  20  which holds the patron walkway  14  and ramp  12  actuator mechanisms  70 ,  34 . When the vehicle leaves the platform from this position, the platform reconfigures itself from the deflected (straight and horizontal) position  84  to the unloaded (cambered upward one inch) position  86 . In this orientation, the platform has much less volumetric holding capacity and essentially discharges the bulk of its fluid into the pit as the vehicle leaves the platform. Calculations indicate that approximately 75% of the fluid volume is discharged in this fashion.  
         [0041]    Furthermore, the platform drains itself at the preferred lowest position on the tower, without the need for active devices or drain plugs. When the next vehicle drives onto the platform, if there is no fluid released from it, there is a substantial surplus (75%) of fluid capacity which provides a relatively drip-free movement of the platforms as they rotate around the tower. Draining the platform at the lowest position minimizes possible sloshing and splashing of falling fluids from moving platforms.  
         [0042]    To operate the vertical conveyor system a user first selects a container to access. The carousel rotates, presenting the selected container at an accessible position. Generally, this position is at the bottom of the carousel. Next, the walkway and ramp are moved into position. The height of the container dictates the precise positioning of the walkway and ramp. A conveyor system of the present invention normally includes both short and tall containers. Therefore, the ramp and walkways will move into one of two accessible positions, either a short container accessible position, or a tall container accessible position. With the ramps and walkways in position, vehicles and patrons may access the pan of the container. To allow access to other containers, the carousel once again rotates. However, before doing so, the walkway and ramps must be moved into neutral positions. For the walkway, the typical neutral position is within the pit. The ramp, in contrast, moves upward into a substantially vertical orientation. By way of summary, a walkway and ramp each have three possible positions: neutral position, a short container accessible position, and a tall container accessible position.  
         [0043]    While the advantageous vertical conveyor of the present invention has been illustrated in specific preferred embodiments herein, those skilled in the art will understand that various modifications of the advantageous device of the present invention may be made without departing from the scope and spirit of the invention as stated in the following claims.

Summary:
A vertical conveyor device to accommodate motor vehicles of varying height. Short and tall containers for motor vehicles alternate around a vertical carousel. When a container is placed in an accessible position, movable walkways and ramps change position allowing patrons and vehicles access to the containers. The position of the walkway and ramp vary depending on the height of the container.