Dimpled door hardware

An over-the-road vehicle in the nature of a trailer or a van has a body provided with an open end formed by oppositely disposed side pillars, a header and a sill. A pair of doors are hinged to the pillars with channel members secured near the opposite door edges having bearings at the ends in which locking rods are secured against edgewise movement while being pivotally mounted within the channel members. The ends of the rods are supported in cantilever from the ends of the channel members having on the ends a cam finger which engages cams within castings secured to the header and sill by which the doors are moved to secured closed position when the rods are rotated. When a load is applied to the inner surface of the door, the ends of the locking rods will bend from the ends of the channel members providing a bending moment from the channel ends to the ends of the rods. When the force is substantially increased, the rods will engage the edge of the door to change the length of the bending moment arm thereby withstanding the increased load without any permanent damage to the hardware or door edge.

BACKGROUND OF THE INVENTION 
Reference may be had to the following patents which have been uncovered and 
which has bearing on the disclosure covering door hardware. U.S. Pat. Nos. 
297,262; 1,100,820; 1,197,188; 1,277,622; 1,500,169; 1,729,039; 1,760,173; 
2,738,297; 2,944,303; 2,986,244; 3,173,383; 3,362,737; 3,434,751; 
3,572,794; 3,627,366; 3,633,954. 
SUMMARY OF THE INVENTION 
The invention pertains to hardware for a door edge opposite to that which 
is supported on hinges. A channel shaped element having oppositely 
extending flanges is mounted on the door to provide reinforcement therefor 
adjacent to the free edge. The top and bottom ends of the channel element 
have a plate welded thereover containing a U-shaped recess at one side and 
a central aperture on the opposite side. A locking rod is supported in 
said U-shaped recesses at the top and at the bottom and a plate is secured 
thereover having a rest pad which extends over and closes the end of the 
U-shaped recess. The lock rod has a collar at the top and bottom which 
engages the closure plate and forms a bearing cup for supporting the lock 
rod against endwise movement while permitting it to rotate within the 
channel shaped element. The lock rod projects beyond the bearing cups at 
the top and bottom and forms a cantilever support for the lock rod ends 
which provide a moment arm along the rods from the bearing cups to the 
ends. The ends of the rod have locking cam elements thereon which when 
rotated to door-closed position engages the cam surfaces on castings 
supported on the header and sill for drawing the doors into closed latched 
position. 
The door has a flat outer panel and an inner panel provided with large 
truncated conical dimples alone or with rows of narrow extending 
depressions. The inner flat edge of the dimples and the flange at the 
panel edges are spot welded to the outer panel with the extending portion 
of the outer panel edge reversely bent over the flange welded adjacent 
thereto to form the door edge. The edge is located adjacent to a sloping 
wall on the inner panel which provides strength to the edge of the 
assembly. The door formed in this manner was found to resist distortion 
when substantial force was applied over the entire inner surface thereof. 
This force causes the ends of the locking rod to deflect from the 
cantilever supported end an amount which caused no damage to the hardware. 
When the load is substantially increased, a shorter moment arm results 
when the ends of the locking rod engage the adjacent edges of the door to 
further resist deflection. When the load is substantial in the nature of 
40,000 pounds, some slight deflection will be noted in the door edge but 
no harm resulted therefrom.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring to the Figures, an over-the-road vehicle in the nature of a 
trailer or van 11 has a rear opening 12 defined by side pillars 13 and 14, 
a header 15 and a sill 16. A pair of doors 17 and 18 are secured by hinges 
19 to the pillars 13 and 14. Each door has an outer panel 21 of a plain 
sheet of metal and an inner panel 22 containing a plurality of truncated 
conical dimples 23. Elongated depressions 24 may be provided between the 
dimples both lengthwise and transversely of the rows thereof. The outer 
edges 25 of the inner panel slopes outwardly with the outer edges forming 
flanges 26. The corners of the panel 22 are so cut that after bends 27 and 
28 are formed therein the metal thereat is in engagement forming a closed 
corner. The outer panel rests upon the inner panel and the inner wall 29 
of the dimples are spot welded to the inner face of the outer wall 21. The 
flanges 26 about the edges of the inner wall are spot welded to the inner 
surface of the outer panel with a flange 31 about the outer panel 
reversely bent back over the welded flanges 26 of the inner panel. 
Truncated conical dish shaped elements 32 are placed in certain of the 
truncated conical dimples, as illustrated in FIG. 5, which may be spot 
welded to the dimples or which may be secured thereto by bolts 33 which 
secure the hinges 19 to the doors, as illustrated in FIGS. 1 and 5. A dish 
shaped end 34 is likewise secured in a dimple at the edge of the door 
opposite to that having the hinges 19 thereon and extends forwardly of the 
flange 31 at 35 to provide an anti-theft plate over which the adjacent 
door edge extends to prevent the door from being opened. A bracket 36 is 
also welded to the outer panel in alignment with the weld of the dish 
shaped element 34 having an aperture 37 therein containing a chain 38 
having a pin (not shown) on the end which can be placed in an eye on the 
body side to retain the door open thereagainst. The edge of the lefthand 
door has a sealing gasket 39 secured therealong which is provided with a 
pair of lips 41 and 42 which receives the opposite door edge and forms a 
seal therealong when the doors are drawn into clamped relation at the end 
of the closing movement. 
Channel shaped elements 43 have outwardly extending flanges 44 secured by a 
plurality of rivets 45 to the door face to provide reinforcement therefor 
and to encompass locking rods 46 which are journaled therein. The channel 
shaped elements are enclosed at each end by a plate 47 having a U-shaped 
opening 48 at the inner side which is closed by a rest pad 49 and a plate 
51 after the locking rods are placed therein. A bearing sleeve 52 is 
secured at each end of the locking rods 46 to prevent the axial movement 
of the locking rod while permitting them to be rotated. The ends of the 
locking rods 46 have arcuate fingers 53 which extend within the castings 
54 which are aligned therewith on the header 15 and the sill 16. The 
casting is the same or similar to that disclosed in U.S. Pat. No. 
3,633,954, issued Jan. 11, 1972 for Unit Door Closure and Latch which was 
assigned to the assignee of the present invention. As the doors are pried 
to closure position, the edge of the righthand door is sealed between the 
lips 41 and 42 of the resilient strip 39 secured to the lefthand door 
edge. 
The locking rod 46 has a bracket 55 extending from one side thereof near 
the bottom below the end of the channel element 43 with a lever 56 secured 
thereto by a pivot 57. The locking rod is rotated into camming position by 
the lever 56 which may be locked in door-closed position by a pivoted link 
58 which covers a bracket 59 in which the lever rests and which may be 
secured by a lock, the clasp of which extends through aligned apertures 61 
in the link and bracket. When in locked position, the door, substantially 
reinforced by the dimples 23 and depressions 24, can withstand a 
substantial force when applied over the entire inner door surface. The 
ends of the locking rods extending beyond the bearing sleeves 52 will 
deflect thereat providing a moment arm from the sleeve to the end of the 
locking rods. 
When 10,000 pounds is applied in this manner, the ends of the locking rods 
will deflect and spring back to their original position when the load is 
removed. A greater force in the order of 20,000 pounds, when applied over 
the inner door surface, will cause the ends of the locking rods to deflect 
an amount to engage the edge 62 at the top and bottom of the door. This 
will substantially shorten the moment arm to that from the edge of the 
door panel to the end of the locking rods. Upon the release of the force 
applied over the entire inner surface of the door, the locking rod will 
move back to its original position without any set therein or in the door 
edge. When 40,000 pounds was similarly applied to the inner surface of the 
door, the deflection of the locking rods is such as to have them engage 
the edge of the door with such force as to cause a slight deflection to 
the door edge which is permanently set when the force is removed without 
any damage whatsoever occurring to the locking rod or to the panels other 
than that at the edge of the door. 
The tests have proved conclusively that the employment of the truncated 
conical dimples with or without the elongated depressions on the inner 
door panel with the inner edges of the dimples welded to the outer door 
panel, provides substantial rigidity and strength thereto. The use of the 
channel elements near the free edge of the door provides further 
reinforcement thereto and a support for enclosing the major portion of the 
locking rods. The end portions of the locking rods from the ends of the 
reinforcing channel element are supported in cantilever and deflect 
therefrom when a substantial load is applied over the inner surface of the 
doors. The moment arm, from the bushings at the end of the channel element 
to the locking rod end, is substantially reduced in length when a greater 
load is applied over the inner door surfaces. The locking rod ends deflect 
a greater amount so that the door edge is engaged thereby to reduce the 
length of the moment arm and provide greater resistance to the applied 
force. This change in the length of the moment arms was found to provide 
added strength against the setting of the metal of the locking rods, the 
door panels or door edges to prevent permanent damage thereto even under 
the severe loads applied over the surface of the doors.