Abstract:
A storable bed assembly primarily for recreational vehicles permits the lowering and raising of the bed using a pair of rear guides fixed to a wall of the recreational vehicle, and a pair of swing arm guides at the front corners of the bed frame. Linkages are provided to couple the corners of the bed frame to the guides. Counterbalancing springs in the form of compressed gas cylinders are provided to assist in raising the bed assembly to the stored position.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
       [0001]    This application is a continuation of U.S. patent application Ser. No. 09/945,400, filed Aug. 31, 2001, now U.S. Pat. No. ______ TBD 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    This invention relates to movable bed assemblies, primarily for use in limited space facilities such as travel trailers.  
           [0003]    Various arrangements have been proposed heretofore for shifting beds from a stored overhead position where the bed is out of the way, to a lower position where the bed is to be used for sleeping. Representative prior art arrangements of this type are shown in U.S. Pat. Nos. 6,231,114B1, 3,266,062, 3,623,168, and 3,829,907.  
           [0004]    However, these prior proposed arrangements have significant shortcomings in that they may be unduly complicated, inconvenient to use, or may require considerable care by the user to avoid possible injury.  
         INVENTION SUMMARY  
         [0005]    Accordingly, objects of the invention include simplicity, convenience, and design safety so that the bed may be easily raised and lowered without danger of injury to the user.  
           [0006]    In one exemplary embodiment illustrating the principles of the invention, a travel trailer includes a bed mounted at one end of said trailer with the rear of the bed mounted against one side wall of said trailer, and sides of the bed being adjacent the two side walls of the trailer. The bed may include a mattress and a frame; and the rear of the frame is mounted on two substantially vertical rear guides. Toward the front of the bed frame, linkages are provided which slidably engage swing arms to permit lowering and raising of the bed. The swing arms are pivotally mounted to the sides of the trailer, and have lower end points which arrest downward movement of the front of the bed frame. Resilient counterbalancing arrangements are provided, which are compressed when the bed is shifted to its lower position, and which assist in shifting the bed and frame to its upper stored position.  
           [0007]    The counterbalancing arrangements may involve compressed air or gas, or elongated springs; and may be combined with the slides and swing arms, or may be separate therefrom.  
           [0008]    The swing arms may include front guides; and the linkages mounted near the corners of the bed frame may each have a pair of rollers which are trapped within the guides.  
           [0009]    The storable bed assembly may also be employed in other applications, including other recreational vehicle applications such as motor homes or campers.  
           [0010]    The counterbalancing arrangements may be in the form of gas springs, or coil springs, for examples.  
           [0011]    Advantages of the invention include improved safety and convenience in lowering and raising the bed. For example, the front of the bed may be provided with a handle to pull the front of the bed down; and then pressing on the surface of the bed will lower the back of the bed so that it is in the lower sleeping configuration.  
           [0012]    Other objects, features and advantages of the invention will become apparent from a consideration of the following detail description and the accompanying drawings. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]    [0013]FIG. 1 is a side cross-sectional view of a recreational vehicle showing one typical location for a pull-down bed illustrating the principles of the invention;  
         [0014]    [0014]FIG. 2 is diagramatic side view of a pull-down bed illustrating the principles of the invention with the front of the bed having been shifted downward;  
         [0015]    [0015]FIG. 3 is a side view similar to that of FIG. 2, but with both the front and the rear of the bed having been shifted downward;  
         [0016]    [0016]FIG. 4 is a cutaway schematic perspective view of the bed frame and the four vertical guides which permit easy lowering and raising of the bed;  
         [0017]    [0017]FIG. 5 is an enlarged showing of the portion of the drawing of FIG. 4 indicated by the number “5”, referring to a circle in FIG. 4;  
         [0018]    [0018]FIG. 6 is a detailed and enlarged showing of the portion of FIG. 4 indicated by the dash, dot circle “6” of FIG. 4;  
         [0019]    [0019]FIG. 7 is a top view of the front corner of the bed; and  
         [0020]    [0020]FIG. 8 is a top view of one of the rear corners of the bed that is shown in FIG. 6. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0021]    Referring now to FIG. 1 of the drawings, an overall view of a trailer body  12  is presented, with a storable bed  14  being shown mounted at the rear of the trailer, with the bed  14  in the raised stored position. With regard to the storable bed  14 , it includes a mattress  16  and a bed frame  18 . FIG. 1 also shows a pair of rear vertical guides or tracks  20 , and a pair of front swing arms  22 , each of which also includes a guide or track.  
         [0022]    In FIG. 1 of the drawings, the bed  14  was shown in its upper or fully stored position, where it is out of the way so that the space underneath the bed  14  may be used. When it is desired to use the bed, it is lowered in two steps. As the first step, shown in FIG. 2, the front of the bed is shifted downward until the linkages  24  secured to the front sides of the bed engage stop members  26  toward the bottom of the swing arm guides  22 , thus defining the lower position of the front of the bed.  
         [0023]    The showing of FIG. 3 illustrates the bed  14  in its lower position, ready for use as a regular bed for people to sleep on. In this showing of FIG. 3, one of the rear linkages  28  is shown engaging a stop  30  to define the lower position of the rear of the bed. Also shown in FIG. 3 is the upper stop  32  which defines the upper or stored position of the bed frame, when the linkage  28  secured to the bed frame  18  engages this top stop  32 . The rounded rectangle  34  as shown in FIGS. 1, 2 and  3  is merely a window in the side of the trailer.  
         [0024]    Also shown in FIGS. 1, 2 and  3  are the spring struts  36  and  38  which are compressed when the bed is lowered, and which provide upward force that is desired to return the bed to the stored position. This strut  36  is secured to the bed frame at point  40  and to a fixed reinforcing panel  42  at pivot point  44 . Similarly, the front strut  38  is secured to the support plate  42  at point  46  and to the bed frame at point  48 . Four gas compression spring struts are employed, two on each side of the bed. These gas springs may for example be Part No. GR12.2M-90 made by CBOL Corporation, and they are available from Newport Engineering Associates, Inc., 2950 Airway Avenue, Suite A12, Costa Mesa, Calif. 92626-5031.  
         [0025]    Although gas struts as described hereinabove are preferred, other types of counterbalancing arrangements, such as coil springs, may be used. In addition, if desired, the counterbalancing arrangements may be combined with the guides, so that as the linkage  28  moves downward, a coil spring or gas compression cylinder within the guide, may be compressed, for subsequent release and expansion when it is desired to move the bed to the storage position.  
         [0026]    Reference will now be made to FIG. 4 of the drawing which is a bottom perspective view showing the bed frame, the gas struts and the four guides, in this partially cutaway view. Thus, note that the two front swing arm guide rails  22  and  22 ′ pivotally mounted to the side walls; and the handle  52  in the foreground which is employed to pull the front of the bed down. Note that the two rear guide rails  20  and  20 ′ are mounted on the rear wall of the trailer, and the guide  20 ′ is the furthest away from the viewer when looking at FIG. 4.  
         [0027]    It is useful to note that the drawing of FIG. 5 corresponds to the dash dot oval “5” of FIG. 4 and shows in greater detail the construction of the linkage between the front of the bed frame  18  and the swing arm or guide  22 . Note that the L shape angle iron is part of the bed frame  18 . The swing arm guide  22  is pivotally mounted to the wall of the trailer by the plate  54 , and the rubber stop  56  serves to define the upper position of the bed frame when the linkage  24  engages the stop  56 . FIG. 7 is helpful in showing the upper plate  54  and the roller  58  which is one of two rollers forming part of the linkage  24  for the front of the bed. Also shown in FIG. 5 is one end of the strut  38  which is coupled to the front of the bed frame  18  through the bracket  62 .  
         [0028]    [0028]FIG. 6 is an enlarged showing of the rear guide  20  and the linkage  28  coupling the bed frame  18  to the rear guide track  20 . Also shown in FIG. 6 is the rear end of the strut  36 . FIG. 8 is a top view of the rear guide rail  20 , an extension of the bed frame  18  and the spring strut  36 . The roller  66  forms a part of the linkage  28  by which the rear of the bed frame  18  is mounted to the rear guides or tracks  20 .  
         [0029]    In conclusion, in the foregoing detailed description, one illustrative embodiment of the invention has been disclosed and shown in the drawings. It is to be understood, however, that various modifications and changes may be made without departing from the spirit and scope of the invention. Thus, by way of example and not of limitation, instead of the front guides being pivoted and the rear guides being fixed, the front guides may be fixed and the rear guides arranged to pivot forward, as the front of the bed is lowered. Then, as the rear of the bed is brought down, the rear guides would pivot back to the fully vertical position. It is also noted that instead of rollers within tracks, the pivoted swing arms may be in rod form with the linkages extending around the rods. Also, as mentioned above, the spring struts may involve coil springs for example, instead of the gas strut arrangements as disclosed in detail hereinabove. As another alternative, the front guides may be fixed but arcuate in configuration to conform to the arcuate path of the front linkages as the front of the bed is pivoted down, while the back of the bed remains at the upper level; and the fixed front tracks may then have a short lower horizontal section to permit forward movement of the front linkages as the rear of the bed is brought down. Accordingly, the present invention is not limited to the specific embodiments described in detail and disclosed in the present drawings.