Abstract:
A door structure for a vehicle has a door seated in a door jam frame at the rear end of the vehicle. The door jam fame has a first upright with an opening therein disposed nearby one side of the vehicle to provide a space between this side and the first upright. A second upright is nearby the other side of the vehicle. A hinge member is attached to the door which includes a first connecting member attached to the door member near the one side of the vehicle, a second connecting member pivotally attached to the first upright and disposed in the space between the one side of the vehicle and the first upright, and an intermediate arcuate member connected between the first and second connecting members which extends through the opening in the first upright.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to a door structure for the rear end of a vehicle such as, for example, a hearse. 
     2. Background Discussion 
     Some vehicles, in particular hearses, use a rear door that is mounted to be opened to the left or right, rather than being lowered and raised to open and close. It is desirable to provide such a door which is lightweight yet sturdy, and incorporates many of the desirable features of modern vehicles such as automatic closing mechanisms commonly provided on trunks of automotive vehicles. It is also desirable to provide a hinge mechanism which is reliable, easy to install, low cost to manufacture, and which has an attractive appearance. It is the objective of this invention to provide a door structure with these desirable attributes. 
     SUMMARY OF THE INVENTION 
     This invention has several features, no single one of which is solely responsible for its desirable attributes. Without limiting the scope of this invention as expressed by the claims which follow, its more prominent features will now be discussed briefly. After considering this discussion, and particularly after reading the section entitled, “DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT,” one will understand how the features of this invention provide its benefits, which include low cost, simplified manufacture, reliability, and a streamline hinge appearance. 
     The first feature of the door structure of this invention is that it is particularly designed to be mounted at an open rear end of a vehicle, such as a hearse, between the opposed sides of the vehicle. It includes a door member, preferably having exterior and interior spaced apart wall members made of a light weight, polymeric material. A honeycomb reinforcing member is positioned between the wall members, and a mounting plate made of metal is secured to the interior wall in a position to be nearby one side of the vehicle when the door member is attached to the open rear end of the vehicle. 
     The second feature is that the door structure includes a door jam frame at the rear end of the vehicle in which the door member is seated when closed and from which said door member extends when opened. The door jam fame has a first upright disposed nearby the one side of the vehicle to provide a space between this one side of the vehicle and the first upright. A second upright nearby the opposite side of the vehicle. A hinge member is attached to the mounting plate and extends through an opening in the first upright. 
     The third feature is that the hinge member has a first connecting member attached to the mounting plate, a second connecting member pivotally attached to the first upright and disposed in the space between the one side of the vehicle and the first upright, and an intermediate arcuate member connected between the first and second connecting members which extends through the opening in the first upright. The first connecting member is substantially planar. The second connecting member is also substantially planar and is at an angle in excess of 90 degrees with respect to the second connecting member, preferably from about 120 to about 130 degrees. The intermediate arcuate member has a substantially smooth, continuous, external surface. Such a surface provides an attractive, streamline appearance. Preferably, the arcuate member is a segment of a cylindrical wall. The axis of rotation of the hinge member is the centerline of the cylinder from which the cylindrical wall segment is taken. In other words, the centerline of the segment of the cylindrical wall is coincident with the axis of rotation of the hinge member. The hinge member pivots around this centerline as the door member is opened and closed. There are walls adjacent the hinge member which are covered with a decorative material. These walls are positioned so that only the arcuate member of the hinge is exposed as the door is opened and closed. 
     The fourth feature is that a mounting member is attached to the door jam frame in a fixed position in the space between the one side of the vehicle and the first upright. This mounting member has a cam surface thereon, with a portion which acts to hold the door member in an open position when engaging a cam follower. The hinge member has a cam follower attached to it. This cam follower, when the door member has been partially opened, engages the cam surface, and, when the door member has been opened to a predetermined maximum open position, it engages the stop to hold the door member in the predetermined maximum open position. 
     The fifth feature is a latch mechanism attached to the door member. The exterior wall member has a handle member therein near the opposite side of the vehicle which, when activated, engages and disengages the latch mechanism. A striker mechanism is provided having a motor which pulls the door into the door jam frame when the latch mechanism initially contacts the striker mechanism. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING 
     The preferred embodiment of this invention, illustrating all its features, will now be discussed in detail. This embodiment depicts the novel and non-obvious door structure of this invention as shown in the accompanying drawing, which is for illustrative purposes only. This drawing includes the following figures (FIGS.), with like numerals indicating like parts: 
     FIG. 1 a  is a perspective view of the rear end of a hearse showing the door structure of this invention hingedly mounted to the left side of hearse. 
     FIG. 1 b  is a perspective view of the hearse shown in FIG. 1 a  with the door structure open completely opened. 
     FIG. 2 a  is a rear elevational view of the hearse shown in FIG. 1 a.    
     FIG. 2 b  is an enlarged, fragmentary view of the rear end of the hearse shown in FIG. 2 a.    
     FIG. 3 is an enlarged, fragmentary view, with sections broken away, showing a hinge attached to a mounting plate on the rear door. 
     FIG. 4 a  is a hearse, elevational view, with sections broken away, showing a handle in the rear door operatively attached to a latch mechanism. 
     FIG. 4 b  is a view similar to that shown in FIG. 4 a  showing the handle moved to a position which disengages the latch mechanism. 
     FIG. 5 is a cross-sectional view taken along line  5 — 5  of FIG. 2 a  showing the rear door in a partially opened position. 
     FIG. 6 is a cross-sectional view similar to that shown in FIG. 5 with the door being closed. 
     FIG. 7 is a cross-sectional view similar to that shown in FIG. 6 with the handle in the rear door lifted and the latch mechanism being disengaged to open the door. 
     FIG. 7 a  is an enlarged cross-sectional showing the cam mechanism and cam wheel. 
     FIG. 8 is a perspective view showing the door in a partially opened position, illustrating the manner in which the hinge is attached to the interior wall of the door member. 
     FIG. 9 is a perspective view with the hinge shown in phantom, illustrating the cam wheel engaging the cam surface of the door holding mechanism employed in this invention. 
     FIG. 10 is an end elevational view of the upright adjacent the left side of the vehicle, with the door member attached to this upright in the fully open position. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     As illustrated in FIGS. 1 a  and  1   b,  a hearse  10  is equipped with the door structure  12  of this invention, which includes a door  14  mounted by a hinge  16  to the left side of the hearse so that the door can swing to towards the left side of the hearse upon being opened. When closed, the door  14  fits snugly within a door jam frame  18  located in the open rear  10   a  of the hearse  10 , as illustrated in FIG. 1 a.  The door  14  optionally could be mounted to the right side of the hearse  10  so that it would swing to the right upon being opened. 
     As shown in FIG. 1 b,    3 , and  5  through  7 , the door  14  includes an interior wall  14   a  and an exterior wall  14   b,  preferably made of a lightweight, durable, composite material, such as a polymeric material like fiberglass. A honeycomb reinforcing member  20  is disposed between the interior and exterior walls  14   a  and  14   b  to provide structural rigidity to the door  14 . There may be openings in the door  14  such as a window  22  (FIGS. 1 a  and  1   b ), and the entire area between the interior and exterior walls need not be filled completely with the honeycomb reinforcing member  20 . A marginal end wall  14   c  surrounds the honeycomb reinforcing member  20 , providing an enclosure for the honeycomb reinforcing structure. A generally square shaped, metal mounting plate  24  is imbedded inside the door  14 , forming a part of the interior wall  14   a.  An epoxy resin adhesive may be used to secure this metal mounting plate  24  in position adjacent the left side of the hearse  10 , to which the door  14  is connected. 
     The door jamb frame  18  has a top  18   a  and a bottom  18   b,  and opposed left and right uprights  18   c  and  18   d,  respectively. Both the left and right uprights  18   c  and  18   d  are spaced inwardly from the sides of the hearse  10  to provide, respectively, the spaces  28   c  and  28   d.  As best illustrated in FIGS. 5 through 7, the space  28   c  is between the left side of the hearse  10  and the upright  18   c  and the space  28   d  is between the right side of the hearse  10  and the upright  18   d.  The left upright  18   c  is covered with a decorative cover  19 . 
     As best shown in FIGS. 9 and 10, the left upright  18   c  to which the hinge  16  is attached has cutaway sections that provide openings  30  and  32  that allow the hinge  16  to move through these openings as the door  14  is opened and closed. An extension section between these openings  30  and  32  provides a mounting plate  34  for a cam mechanism  36  which is attached to this plate as illustrated in FIGS. 5 through 7. A cam wheel  40  mounted on a bracket  40   a  carried by the hinge  16  engages the cam mechanism  36  as the door is closed as discussed subsequently in greater detail. The mounting plate  34  is bend inward towards the left side of the hearse  10 , so that it is disposed in the space  28   c.  A stop  38  is formed in this upright  18   c  in its lower portion. This stop  38  engages the hinge  16  member when the door  14  is in its maximum open position, as shown in FIG. 1 a  and in dotted lines in FIGS. 5 and 10. 
     As best depicted in FIGS. 8 and 9, the hinge  16  is a unitary, piece of metal, preferably steel, having a generally flat planar connecting member  16   a  attached by hinge pins  46  inserted into triangular shaped mounting brackets  48  secured by bolts to the left upright  18   c  on the inside of this upright in the space  28   c,  respectively at the top and bottom of this upright. A second, generally flat planar connecting plate  16   b  is bolted to the mounting plate  24 . The two connecting plates  16   a  and  16   b  are disposed relative to each other at an angle A greater than 90 degrees, preferably at an angle of 125 degrees. These two connecting plates  16   a  and  16   b  merge with an arcuate member  16   c  of the hinge  16 . This arcuate member  16   c  has a solid, smooth, continuous, exposed surface S that has an attractive appearance when the door  14  is opened, as illustrated in FIG. 1 b.  This arcuate member  16   c  is a segment of a cylindrical wall where the centerline C of the cylinder is coincident with the axis of rotation of the hinge  16 . As illustrated in FIG. 5, the walls  50  and  52  of the rear loading section  10   b  of the hearse  10  are adjacent this arcuate member  16   c.  The wall  50  is attached to the left inside of the rear loading section  10   b,  and the wall  52  is attached to the interior wall  14   a  of the door  14 , and moves with the door. These walls  50  and  52  are covered with a decorative material and spaced apart to provide a relatively narrow gap  56 , which increases and decreases in width as the door  14  is opened and closed. Regardless of the position of the door  14 , the gap is nevertheless restricted in width, so that only the smooth, continuous, surface S is exposed to view. 
     As best shown in FIG. 8, the connecting member  16   a  has centrally located therein an enlarged, square opening  60 . The bracket  40   a  for cam wheel  40  is attached to this connecting member  16   a  and the cam wheel is positioned at the square opening  60  so that, when the door  14  is partially opened, this cam wheel will engage the cam mechanism  36 . As best shown in FIG. 7 a,  the cam mechanism  36  includes a cam surface  36   a  over which the wheel  40  rides until it comes to an indentation  36   b.  The cam surface  36   a  is the exterior of a leaf spring that has a ramp  36   c  attached at one end to a bracket  36   d  which is bolted by bolts (not shown) passing through a slot  35  in the mounting plate  34 . The ramp  36   c  leads to the indentation  36   b.  A rubber block  66  is disposed between the bracket  36   d  and the underside of the indentation  36   b.  Thus, when the cam wheel  40  rides up the ramp  36   c  and drops into the indentation  36   b,  it will remain in this position, holding the door  14  in its maximum opened position until the door is manually closed. 
     As best shown in FIGS. 4 a  and  4   b  and  5  through  7 , there is a handle  70  in the exterior wall of the door  14  which, upon being lifted upward open the door  14  by disengaging a conventional latch mechanism  72  from a motor driven striker  74 , enabling the door  14  to be opened. This handle  70  is attached to a rod  76  mounted at its ends so that it may rotate. A bent connecting member  78  mechanically couples this rod  76  to the latch mechanism  72 , with one end of the bent connecting member attached by a bar  80  to the latch mechanism, and the other end of this bent connecting member attached by another bar  82  to the rod  76 . Because of this mechanically coupling, lifting the handle  70  as shown in FIG. 7 disengages the latching mechanism  72  from the striker  74 , enabling the door  14  to be opened. A spring  84  coiled around the rod  76  returns the handle  70  to its normally closed position, as shown in FIG.  6 . When the door  14  is closed, as soon as the latching mechanism  72  engages the striker  74 , a motor  88  is activated to pull the door  14  completely and automatically within the door jam frame  18 . Such latching mechanisms  72  and striker  74  are commonly employed in trunks of automotive vehicles, but are not ordinarily used on a door  14  which require a handle that is manually manipulated. 
     SCOPE OF THE INVENTION 
     The above presents a description of the best mode contemplated of carrying out the present invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains to make and use this invention. This invention is, however, susceptible to modifications and alternate constructions from that discussed above which are fully equivalent. Consequently, it is not the intention to limit this invention to the particular embodiment disclosed. On the contrary, the intention is to cover all modifications and alternate constructions coming within the spirit and scope of the invention as generally expressed by the following claims, which particularly point out and distinctly claim the subject matter of the invention: