Abstract:
A door assembly for a recreational vehicle has a molded mounting frame and a molded flange. The mounting frame and the door have integral hinge pin lugs. Spring-loaded hinge pins are captured within the hinge pin lugs and allow the door to swing open or close. A latch secures the door assembly in a closed position. The door may be thermally insulated. The hinge pins may be stainless steel. The latch may be a locking mechanism. The door securely conceals the door frame fasteners when the door assembly is in the closed position. One hinge pin may be fixed to one hinge pin lug.

Description:
FIELD OF THE INVENTION 
     The present invention relates to doors. More particularly, the invention relates to compartment doors for recreational vehicles. 
     BACKGROUND OF THE INVENTION 
     Every year, thousands of vacationers load necessary equipment and supplies into recreational vehicles (R.V.&#39;s) and venture across the countryside. Many R.V.&#39;s incorporate all of the luxuries of a permanent residence. These roving homesteads often have full bathrooms, ample sleeping quarters, and kitchens with sinks, stoves and microwave ovens. Integrating these numerous features into a road-worthy vehicle is a difficult task. 
     The overall size of an R.V. is constrained by Department of Transportation limitations and operator maneuverability considerations. Designers must allocate space between permanent fixtures and storage areas because of this size limitation. Storage space is limited because other fixtures consume interior space. R.V. manufacturers alleviate this problem of limited interior storage space by installing exterior doors that allow access to otherwise inaccessible areas. 
     Exterior storage doors for recreational vehicles have many inadequacies. Currently available doors have many pieces that require labor intensive manufacturing and assembly processes. These doors consequently are expensive for the consumer. Many small parts also increase chances for mechanical failure. 
     Expense and fragility are not the only problems associated with currently available R.V. doors. Some exterior doors have exposed hardware, bulky profiles or seams that cause additional problems. Exposed and/or protruding components of an exterior door can be easily vandalized or damaged and do not provide necessary security for compartment contents. They can also increase the vehicle&#39;s overall coefficient of drag, which reduces fuel economy. Seams can leak. 
     R.V. manufacturers accordingly need a reliable exterior door system with few components to supply the consumer with a quality door at an affordable price. 
     SUMMARY OF THE INVENTION 
     The present invention is an improved door assembly for a recreational vehicle that comprises a mounting frame that has integral hinge pin lugs. The mounting frame is preferably integrally molded plastic. The hinge pin lugs on the mounting frame correspond to integral hinge pin lugs on a door. Spring-loaded hinge pins are captured within the hinge pin lugs. A latch secures the door assembly in a closed position. The latch may include a locking mechanism. The door is thermally insulated in one embodiment of the invention. The door securely conceals the mounting frame fasteners/hardware when the door assembly is closed in another embodiment. One hinge pin may be fixed to a hinge pin lug in another embodiment of the invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a plan view of the door assembly; 
     FIG. 2 is a cross section of the door assembly along line  2 — 2 ; 
     FIG. 3 is a cut away detail of the hinge assembly; 
     FIG. 4 is a plan view of the core frame; 
     FIG. 5 is a plan view of the door frame; 
     FIG. 6 is a plan view of the core retainer; 
     FIG. 7 is a plan view of the door core; and 
     FIG. 8 is an exploded perspective view of the door assembly. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring initially to FIG. 1, the R.V. door according to the present invention has a door frame  2  with two frame lugs  4  (also shown in FIG.  5 ). The door frame  2  may be injection molded with high-impact plastic and preferably has molded, one-piece flange  3  around the perimeter. The molded construction is preferred because it eliminates a butt seam in the frame  2  and flange  3  that could be sources of leaks. The frame  2  may also be made from aluminum, fiberglass, carbon fiber or some other suitable material used by persons with ordinary skill in the art, with or without a butt-seam. The frame  2  may be attached to a recreational vehicle (not shown) through the flange  3  with screws, bolts, rivets, adhesive or any other method of fastening. A plurality of fastening holes  5  are formed around the flange  3  (also shown in FIG.  5 ). The flange  3  is substantially flush with the surface of the recreational vehicle. 
     A core frame  8  (also shown in FIG. 4) with two core frame lugs  10  fits within the door frame  2 . A door core  6  (also shown in FIG. 7) is sandwiched between the core frame  8  and a core retainer  12 . The core frame  8  and the core retainer  12  (also shown in FIG. 6) are typically injection molded with the same high-impact plastic as the door frame  2 . The core frame  8  and the core retainer  12  may also be made from aluminum, fiberglass, carbon fiber or some other suitable material to those with ordinary skill in the art. Screws (not shown) that pass from the core retainer  12  into the core frame  8  secure the door core  6  between the core frame  8  and the core retainer  12 . The door core  6  may also be secured between the core frame  8  and the core retainer  12  with bolts, rivets, adhesive, or some other method of fastening. 
     The door assembly may be secured in the closed position with a latch  18 . The latch  18  is substantially flush with the exterior of the door assembly to decrease tampering, enhance aesthetic appeal, and maintain vehicle aerodynamics. The latch  18  provides security for the compartment contents by protecting the contents from theft or loss. The latch  18  also provides an external means for opening the door. The latch  18  is a locking mechanism in a preferred embodiment of the invention. Several different locking mechanisms that also open the door may be utilized. A simple keyed lock that engages a locking lever is used in a preferred embodiment. Flush-mounted, paddle-handle or push-button locking mechanisms may also be used. Other suitable latching methods will be obvious to those with ordinary skill in the art. 
     Referring now to FIG. 2, the flange  3  is preferably secured to the wall of the R.V. by means of screws  24  inserted through holes  5  (shown in FIG.  5 ). Core frame  8  is constructed with a frame screw cover lip  28  that, when closed, is disposed over the screws  24 , thus concealing them and preventing their loosening. On the side of core frame  8 , having core frame lug  10 , the lug  10  includes a screw lug cover face  28  that when the frame  2  is in the closed position, also prevents their loosening. 
     The door core  6  (also shown in FIG. 8) may be made from a layer of core insulation  20  sandwiched between two core panels  22 . The door core  6  protects the contents of the compartment from either hot or cold environmental conditions and from external impact. The core insulation  20  may be a variety of insulating materials, for example, Reactive Hotmelt Polyurethane Adhesive. The core insulation  20  adds rigidity and R-value to the door assembly. Core panels  22  may be sheets of aluminum, fiberglass, or any other suitable material. A combination of core panel materials may be used to fit a particular application. A door core  6 , for example, may have a fiberglass core panel  22  on the exterior face and an aluminum core panel  22  on the interior face. 
     As best illustrated in FIG. 3, the core frame lugs  10  align with the frame lugs  4 . Cavities in the core frame lugs  10  accept a pin  14  and a spring  16 , which is compressed for assembly. The pin  14  is ideally made from a non-reactive material, for example, stainless steel. The spring  16  forces the pin  14  from the cavity (as shown) in the core frame lug  10  into the cavity in the frame lug  4 . The pin  14  may also be forced from the cavity in the frame lug  4  into the cavity in the core frame lug  10 . The spring  16  holds the pin  14  in compression between the cavities in the lugs  4 ,  10 . The lugs  4 ,  10  are free to rotate about the axis of the pin  14  to allow the door assembly to be opened or closed. The lugs  4 ,  10  and the pin  14  have a relatively frictionless interface that eliminates the need for lubrication and are virtually maintenance-free. The lugs  4 ,  10  also conceal the pin  14  when assembled, which enhances security and increases aesthetic appearance. 
     It should be appreciated from the above description that many different configurations of the hinge joint and pin  14  are contemplated. A door assembly may incorporate a single pin  14  that passes through a channel in a core frame lug  10  and engages two frame lugs  4 , which are positioned on either end of the core frame lug  10 . Such a configuration would be similar to a wristwatch pin that fastens a watch bracelet to a watch. 
     In another embodiment, two or more hinge joints may be utilized to hinge the frame  2  to the core frame  8 . A door assembly having two hinge joints may have one hinge joint with a fixed pin  14  in the cavity of the frame lug  4 . A door of this configuration is assembled by inserting the protruding end of the fixed pin  14  into the cavity of one core frame lug  10 . A pin  14  and spring  16  is inserted into the cavity of the other frame lug  4 . The other core frame lug  10  may be concentrically aligned with the corresponding frame lug  4  by depressing the pin  14 , which compresses the spring  16 , and aligning the frame lug  4  with the core frame lug  10 . Releasing the pin  14  allows spring  16  to partially decompress and urge a portion of the pin into the cavity in the core frame lug  10 . 
     The fixed pin  14 , alternatively, may be fixed in a cavity of the core frame lug  10 . Assembly is essentially the same as described above except that the protruding end of the fixed pin  14  is inserted into the cavity of one frame lug  4 . The pin  14  and spring  16  are positioned in the opposite lugs and the door assembly is complete.