Abstract:
Door assembly includes a doorframe that can be secured to the vehicle, and a preferably rigid door that is movable between an open and closed position. The door can be secured to the vehicle in the open position so that the passengers have the option of riding in the vehicle while the door remains open. A hinge system minimizes the clearance necessary to open and close the door, and provides an optional assist feature that helps urge or bias the door to the open or closed position and maintain it there.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     Enclosures for vehicles, including battery powered or gas or diesel powered vehicles such as recreational vehicles, utility terrain vehicles (UTV&#39;s), such as the Kobota RTV and Polaris RANGER, golf carts, neighborhood electric vehicles (NEV&#39;S, which can be street-legal), tractors, and other 2-wheel drive, 4-wheel drive, all-wheel drive capable vehicles, on or off-road, to enclose a passenger compartment and/or protect the occupants from inclement weather, are well known. In general, cabs for such vehicles utilize conventional front or rear hinged doors. In addition to being unattractive, such enclosures suffer from various drawbacks, including difficulty in obtaining ingress and egress from the passenger compartment, lack of durability, a requirement that the doors remain closed during operation of the vehicle, unattractiveness, etc.  
         [0002]     For example, U.S. Pat. No. 6,293,610 to Howard discloses a door system for a golf cart-like street legal vehicle. A pair of hinged doors is removable from framework on each side of the vehicle. The framework is permanently mounted to existing structure on the vehicle.  
         [0003]     None of the foregoing embodiments provides an aesthetically pleasing, durable, weather resistant, and easy to operate door system for vehicles such as utility terrain vehicles. In addition, none provides a door assembly where the door can be stored in the open position in an aesthetically pleasing manner and without risk of it unexpectedly and/or undesirably slamming shut during movement or sudden stopping of the vehicle.  
       SUMMARY OF THE INVENTION  
       [0004]     The problems of the prior art have been overcome by the present invention, which provides a door assembly for a vehicle such as a utility vehicle. The door assembly includes a doorframe secured to the vehicle, and a preferably rigid door that is movable between an open position allowing ingress and egress from the vehicle, and a closed position. The door can be secured to the vehicle in the open position so that the passengers have the option of riding in the vehicle while the door remains open. Preferably the door is contoured to match the contour of the vehicle, so that even when the door is stored in the open position, the vehicle remains aesthetically pleasing. A hinge system is utilized that minimizes the clearance necessary to open and close the door, and provides an optional assist feature that helps urge or bias the door to the open or closed position and maintain it there. Preferably the hinges are virtually hidden from view when viewed from the exterior of the vehicle, and are completely hidden when so viewed when the door is in the closed position. The door assembly remains aerodynamic and aesthetically pleasing whether in the open or closed position. Minimal modification of the vehicle is necessary to install the door assembly. A simultaneous or near simultaneous dual latching system is used to ensure a good seal when the door is closed. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0005]      FIG. 1  is a perspective view of a utility terrain vehicle equipped with the door assembly in accordance with the present invention;  
         [0006]      FIG. 2  is a perspective view of a utility terrain vehicle equipped with the door assembly, shown in the open position, in accordance with the present invention;  
         [0007]      FIG. 3  is a perspective view a doorframe in accordance with the present invention;  
         [0008]      FIG. 4  is a front view of the doorframe of  FIG. 3 ;  
         [0009]      FIG. 4A  is a perspective view of a striker assembly mounted on the doorframe of  FIG. 3 ;  
         [0010]      FIG. 5  is a front view of the doorframe of  FIG. 3  shown with a door attached in an open position;  
         [0011]      FIG. 6  is a rear view of the doorframe and open door of  FIG. 5 ;  
         [0012]      FIG. 7  is a perspective view of a door hinge assembly;  
         [0013]      FIG. 8  is a perspective view of the doorframe and door assembly showing the door in open and closed positions;  
         [0014]      FIG. 9  is a first perspective view of a door latching assembly; and  
         [0015]      FIG. 10  is a second perspective view of a door latching assembly. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0016]     The door assembly of the present invention can be used on vehicles such as recreational vehicles, on or off-road vehicles such as utility terrain vehicles, NEV&#39;s, tractors, 2-wheel drive, 4-wheel drive and all-wheel drive capable vehicles although for ease of illustration, utility vehicles such as the rough terrain vehicles available from Kobota will be exemplified herein. Such vehicles are generally available with 3-cylinder, 4-cycle engines, are diesel powered, are 2-wheel drive or 4-wheel drive capable, weight about 1800 to about 2000 pounds, and have a maximum travel speed of about 25 MPH. Other utility vehicles have a maximum speed of about 40-50 MPH. In general, referring to  FIGS. 1 and 2 , the vehicle  10  has front and rear wheels, a chassis  15 , on which is built a passenger compartment (with suitable seating, generally for two passengers), and a windshield  12 , as shown. Those skilled in the art will appreciate that a roof and windshield  12  can be original equipment or added in the aftermarket.  
         [0017]     A pair of doors  20  in accordance with the present invention is shown in the closed position on opposite sides of the vehicle  10 . One of the doors  20  is shown stored in the open position in  FIG. 2 . In the closed position of  FIG. 1 , the doors close the access opening to the passenger compartment defined in part by the vehicle chassis, the roof and the windshield.  
         [0018]     Preferably the door assembly of the present invention is attached to the vehicle with minimal modification to the vehicle itself, utilizing existing structure. To that end, a doorframe shown generally at  16  in  FIG. 3  includes spaced roof struts  17 A,  17 B that secure to the vehicle such as to the vehicle&#39;s existing roll over protection or operator protection system, which in the embodiment shown, includes four vertical roll posts  301 ,  302 ,  303  and  304 , and horizontal roll posts  305 ,  306 . Thus, suitable brackets  18  secure the roof struts  17 A,  17 B to connection points of the horizontal roll bars  305  and  306 , or could secure directly to the bars. Similarly, suitable U-shaped brackets  118  secure the doorframe roll posts  303  and  304  as shown. A C-shaped bracket  119  secures the doorframe to the existing hip restraint bar (not shown) in the vehicle. Roof strut  17 A connects to top frame member  19  and elongated side member  116 . Similarly, roof strut  17 B connects to side panel  80  as shown. Attachment points of the doorframe  16  may differ depending upon the type of b base vehicle, whether a roof is present as existing structure, whether a roll over protection or operator protection system is present, etc. Alternatively, the doorframe  16  can be formed as an integral part of the roll over protection or operator protection system (e.g., the components can be reinforced to provide the necessary rigidity and integrity to provide operator protection of roll over protection) or other cab frame structure and provided as original manufacturer&#39;s equipment, designed to facilitate the addition of doors. The doorframe  16  also includes opposite elongated side member  117 , and base  218  to which side members  116  and  117  are secured. The base  218  secures to the vehicle, preferably the vehicle chassis, such as with a bolt. Preferably the elongated members  116  and  117  are each a continuous bent piece, and are preferably made of a rigid material, capable of withstanding repeated contact from the door itself. Suitable materials of construction include steel, preferably tubular for increased support, metal, aluminum and plastic, with steel being preferred. Although the doorframe assembly  16  is intended to be permanently mounted to the vehicle and become an integral part thereof (since it does not interfere with a user entering or exiting the vehicle, nor does it interfere with the operation or storage of the vehicle), it can be readily removed if desired. The doorframe defines a doorway, which can be blocked by closing door  20 , as discussed in greater detail below.  
         [0019]      FIG. 4  shows a front view of the doorframe  16 , where one suitable latch system is shown. Mounted to elongated side member  117  is a rotary latch striker mechanism  29 , including a bracket  31  and striker pin  30 . The striker mechanism is more clearly shown in  FIG. 4A . A similar mechanism  29 ′ is mounted on opposite elongated side member  116 , in spaced vertical relation with striker mechanism  29  such that the striker pins  30  an  30 ′ are preferably vertically aligned. However, striker mechanism  29 ′ not only includes striker pin  30 ′, but also a second striker pin  30 ″ vertically aligned with strikers  30  and  30 ′. The striker pins are positioned and configured to engage rotary latches mounted to the door  20 , as discussed in greater detail below.  
         [0020]     Door  20  is designed to fit within the area of doorframe  16  defined by members  116 ,  117 ,  218  and  119  when the door is in the closed position, blocking ingress into and egress from the passenger compartment, and preferably closing in a weather-tight manner. The environment within the compartment defined with the doors closed can be controlled. Preferably the door  20  is made of a sturdy, durable, rigid material that can withstand harsh environmental conditions, and protect the passengers from weather. Suitable materials of construction include metal, fiber, fiberglass, stainless steel, aluminum and preferably plastic such as a polyolefin, including polyethylene and/or polypropylene. Preferably the door includes molded plastic supported about its perimeter by a tubular steel framework, and includes a transparent or translucent window portion  200  ( FIG. 1 ) to permit the passengers viewing access to the exterior of the vehicle. The window portion  200  can be formed of any suitable material, such as acrylic, polycarbonate or glass.  
         [0021]     Turning now to  FIGS. 5 and 6 , embodiments of the door hinge assemblies are shown. An upper hinge assembly  40  includes a rigid member  41  such as a threaded rod or a metal strip having a first end pivotally attached to the door  20 , and a second opposite end pivotally attached to the doorframe assembly via bracket  331 . Each of the pivot points can be formed using any suitable means, such as a pin arrangement or a ball and socket joint. Preferably the mounting bracket  331  is located on the interior side of the doorframe assembly as shown. An advantage of mounting the upper hinge assembly in this manner is that most of the mechanism is hidden from outside view, particularly when the door is closed.  
         [0022]     The upper hinge assembly  40  may optionally also include an assist (not shown), preferably a gas spring, compression of which causes energy to be stored in the device. If the assist is used, preferably it is mounted directly below (or above) the rigid member  41  (in the same vertical plane), but with offset pivot points located inwardly of the rigid member pivot points. Suitable pivot mounting configurations include eyelets and ball and socket configurations. When the door is positioned at the midpoint between the open and closed position, the assist is in a neutral position. As the door swings past the midpoint position (either towards a closed position or an open position), the energy stored in the assist is slowly released, causing the rod of the assist to extend, which in turn assists in forcing the door to its closed or open position, as the case may be. When in the open or closed position, the extension of the rod results in the length of the assist exceeding the length of rigid member  41 . This optional assist also can help maintain the door in the open or closed position. Preferably the assist is dampened, so that the door decelerates as it closes.  
         [0023]      FIG. 7  illustrates lower hinge assembly  330 , which preferably includes a pair of spaced rigid members  41 A,  41 B, each having a first end pivotally attached to the doorframe, and a second opposite end pivotally attached to the doorframe, as seen in  FIG. 5 . Preferably the rigid members  41 A and  41 B are not horizontally aligned in order to ensure clearance during operation of the door  20 . The rigid members  41 A and  41 B are of equal length, and are equal in length to rigid member  41  of upper hinge assembly  40 , so that the door remains aligned with the frame. The rigid members  41 ,  41 A and  41 B are all preferably parallel. The particular length chosen for the rigid members depends upon the distance (the diameter of the semi-circle formed during the path of door travel) desired for the door to open/close, as discussed in greater detail below. Each of the pivot points can be formed using any suitable means, such as a bracket  22  and pin  23  arrangement as shown in  FIG. 7 . Preferably at least one of the pin arrangements is adjustable, so that proper alignment of the door is ensured. The lower hinge assembly  330  also preferably includes an assist  35  to help open and close door  20 , such as a gas spring, compression of which results in energy being stored in the device. In the embodiment shown, the assist  35  is located at or near the midpoint between the planes defined by the spaced rigid members  41 A,  41 B. That is, when the lower hinge assembly is in its maximum extended position (i.e., the door is positioned at the midpoint between the open and closed position and is at its farthest point away from the vehicle), the assist  35  is parallel to the rigid members and is located at or near the midpoint between their planes. Accordingly, movement of the rigid members in either direction will cause the assist  35  to expand, thereby assisting in the movement of the door  20 . Alternatively, the assist  35  could be mounted directly below (or above) the rigid member  41 A (in the same vertical plane), but with pivot points located inwardly of the rigid member  41 A pivot points. As with the optional upper hinge assembly assist, when the door is positioned at the midpoint between the open and closed position, the assist  35  is in a neutral position. As the door swings past the midpoint position (either towards a closed position or an open position), the energy stored in the assist  35  is slowly released, causing the rod  36  of assist  35  to extend, which in turn assists in forcing the door to its closed or open position, as the case may be, and maintaining it in that state. The assist  35  can be dampened, so that the door decelerates as it closes. The assist  35  is shorter in length than rigid members  41 A,  41 B and thus one end of assist  35  is fixed to bracket  91 , which is positioned inwardly of bracket  22  for rigid member  41 B, as shown in  FIG. 6 , and the opposite end is fixed to bracket  92 , which is positioned inwardly of bracket  22  for rigid member  41 A, as shown in  FIGS. 5 and 7 .  
         [0024]     Those skilled in the art will appreciate that for optimal operation of the door, at least three rigid members  41  should be used. Although in the embodiment shown, there is one upper rigid member  41  and two lower rigid members  41 A,  41 B, the upper hinge assembly could include two or more rigid members. Similarly, the lower hinge assembly could include only one rigid member  41 , or two or more. The three rigid members define three pivot locations offset from horizontal with respect to each other, and offset vertically from each other. Those skilled in the art will appreciate that more than three pivot locations could be used with out departing from the spirit and scope of the invention.  
         [0025]     Turning now to  FIG. 8 , the motion of the door  20  from the closed state to the open state is shown. As the door is moved from the closed state to the open state. (preferably manually), or from the open state to the closed state (preferably manually), its path of travel defines a semi-circle, as depicted by arrow  100  in  FIG. 8 . The semi-circle so defined is of equal diameter regardless of the reference point of the door used. For example, the semi-circle defined by the path of travel of reference point  90  on the front surface of the door as shown in  FIG. 8  has the same diameter as the semi-circle defined by the path of travel of reference point  91  at the opposite marginal side on the front surface of the door  20 , or for that matter, of any other reference point at any other place, on the same surface of the door. Similarly, the paths of travel of the rigid members  41 ,  41 A and  41 B also define semi-circles of equal diameters as viewed from reference points at the same relative position on each rigid member. As a result, opening and closing of the door  20  can be carried out even when the vehicle is in a confined space. Indeed, substantially less clearance is required than that of a door of identical size that is hinged at one end and swings outwardly, as the maximum distance the door  20  of the present invention moves outwardly from the vehicle is less than the maximum width of the door  20 .  
         [0026]     As seen in  FIG. 8  for example, preferably the lower rearward side of the door  20  (and doorframe  16 ) has a bent portion  110 , angling towards the front of the vehicle and configured to complement the contour of rear wheel fender  101  ( FIG. 1 ) and leave the rear wheel  44  exposed even when the door is in the open position. As a result, when the door is in the open position ( FIG. 2 ), it does not interfere with the operation of the real wheel  44 , and creates an aesthetically pleasing appearance. As indicated above, the distance that the door  20  is designed to open is dictated by the length of the rigid members  41 ,  41 A and  41 B. Accordingly, this length preferably is chosen so that the lower bent portion  110  of the door  20  aligns with the similarly shaped fender (or wheel well) of the vehicle when the door  20  is in the open, stored position.  
         [0027]     Turning back to  FIG. 1 , there is shown front panels  80 ,  80 ′. The panels  80 ,  80 ′ are preferably permanently installed, since they do not interfere with the ingress or egress from the passenger compartment, although the panels could be made to be removable if desired. Each panel is preferably framed as part of the doorframe  16 . The panels  80 ,  80 ′ preferably include a transparent or translucent window supported by the frame and made of acrylic, polycarbonate or glass to enhance passenger visibility.  
         [0028]     To retain or lock the door  20  in its open and/or closed position, a rotary latch system preferably is used. As shown in  FIG. 9 , a pair of rotary latches  120 ,  120 ′ are mounted on the door  20  in spaced location so as to receive in locking engagement a respective striker pin  30 ,  30 ′ when the door is closed. Upon closing the door, the striker pins  30 ,  30 ′ engage respective latch cams in the rotary latches  120 ,  120 ′ and slide back into the latch body along with the cam. The strikers remain within the body of the latch, providing a strong and secure connection. Suitable latches include single actuation and dual actuating rotary latches. On opening, the latch cam rotates out of the body to disengage from the striker pin. Actuation of the rotary latches  120 ,  120 ′ to open the door preferably is carried out simultaneously or nearly simultaneously, using actuating rod or link  130 . The rod or link  130  can be actuated from within the passenger compartment of the vehicle, such as by lifting handle  131  coupled to the rod  130 , or can be actuated from outside the vehicle, such as by depressing plunger  132  on handle  133  ( FIG. 5 ), which communicates with rod extension  135  that is positioned in door aperture  134  and is coupled to the rod  130  via plate  138 . In either case, actuation of rod  130  causes the rod to rotate. The rod includes tabs  136 ,  136 ′ ( FIG. 10 ) that contact respective tabs  140 ,  140 ′ of the latches upon actuation of the rod  130 , rotating the tabs from a striker pin locking position to a striker pin releasing position as shown by the arrows  141  in  FIGS. 9 and 10 . This, in turn, rotates each respective cam in the rotary latch, which disengages the striker pins  30 ,  30 ′, allowing the door  20  to be opened. In view of the simultaneous or near-simultaneous latching that occurs upon the push-to-close and/or gas spring-assisted operation of the door, the door closes in a well-sealed and secure manner. Handle  250  can be provided to assist in operating the door.  
         [0029]     Those skilled in the art will appreciate that the rotary latch could be located on the doorframe, and the striker pins on the door.  
         [0030]     The door also secures (and stores) in the open position by utilizing striker  30 ″, which engages with rotary latch  120  when the door is in its fully opened position, as shown in  FIG. 5 . A similar actuation to that discussed above to rod  130  disengages the rotary latch  130  from striker  30 ″ to close the door. The engagement of striker  30 ″ with the rotary latch  120  can be caused by the force from the stored energy in the gas spring(s), and/or can be caused by manual force applied to the door, such as by applying a pushing force to the outer surface of the door in the general location of the latch mechanism. A similar force can be used to ensure that the door is secured in the open position. The door can be retained in this position even during movement of the vehicle, including speeds of about 40-50 MPH consistent with some of the UTV&#39;s currently on the market.  
         [0031]     An audible “clicking” sound can be heard when the striker pin engages the latch, and where dual actuation latches are used, when the striker pin is further locked in the latch mechanism, thereby confirming the latching.  
         [0032]     In certain instances, such as when the vehicle includes a hydraulically actuated dump bed, it may be desirable to ensure that when the door  20  is in the open, secured position, sufficient clearance between the door and the dump bed is present to allow normal operation of the dump bed without interference from the door. One approach to ensuring such clearance, and also to cushion the door in the open position, is by providing one or more bumpers  400  ( FIG. 3 ) at one or more locations on the door or doorframe. The bumper  400  shown is configured to receive handled  250  of the door  20  when the door is in the open, secured position, such as by having a keyhole shaped opening, and functions to cushion the door and retain it a fixed, predetermined distance from the vehicle (or dump bed, for example). Other bumpers can be placed at the top and bottom of the door, and/or on the rigid member  41  of the upper hinge assembly, for example, to provide further cushioning and/or clearance assurance.  
         [0033]     The doors, together with the windshield, roof and rear panels, combine to enclose the passenger compartment in which the climate, particularly including the temperature but also potentially the humidity, can be further controlled such as with a heating unit that can be installed to supply heat to the compartment. For example, an overhead console can be installed in the compartment, such as by securing it to the roof, or can be mounted to a side frame or behind the dashboard. The unit can include a heating mechanism such as an electric heating element, black heat, or a heater tied to the engine cooling system, and a variable speed fan, as well as multi-direction louvers to aim the airflow. The unit can be wired to the vehicle battery for power. The power supply can relay off the vehicle acceleration pedal so that the unit runs only when the pedal is depressed, thereby avoiding unnecessary battery drain. Alternatively, the power supply can come from the gas-powered or diesel-powered vehicle engine. Cooling air also can be provided.  
         [0034]     In view of the effective seal that is created when the door is closed (the perimeter of the door preferably includes a rubber gasket), and in view of the relatively small passenger compartment, the climate within the compartment can be maintained at an acceptable temperature or within an acceptable temperature range.