Container stacking apparatus

A container stacking apparatus for use in supporting a pair of cargo containers in stacked relation on at least one first cargo container, the container stacking apparatus comprising an elongated frame adapted to be supported on the at least one first cargo container, the elongated frame including a mechanism for supporting the pair of cargo containers in end-to-end relation thereon, a mechanism for releaseably locking the frame down on the first cargo container, and a mechanism for releaseably locking the pair of cargo containers down on the frame.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates generally to the vertical stacking of cargo 
containers, and more particularly, to an apparatus adapted to support a 
pair of cargo containers in double stacked relation on a third cargo 
container. 
2. Reference to Prior Art 
Cargo containers are widely used for hauling freight and are produced in 
various standard sizes which include, among others, containers of 20, 40, 
45, 48 and 53 feet lengths and 96 inch and 102 inch widths. These 
containers are typically provided with cast housings which include locking 
openings used in securing the containers to various vehicles or surfaces. 
The cast housings are positioned in standard arrangements in both the top 
and bottom of the container. For example, a standard arrangement for 40 
feet length cargo containers includes cast housings at each of the eight 
corners of the container. Containers in excess of 40 feet typically 
include intermediate frame structures for locating cast housings 
longitudinally inwardly of the corners so that housing arrangements for 
containers of 40 feet and longer match. 
It is conventional practice to transport cargo containers by rail, with a 
first cargo container being placed in a railroad well car. A second cargo 
container of the same size as the first cargo container, or with a housing 
arrangement which otherwise matches the housing arrangement of the first 
cargo container, can be vertically double stacked on top of the first 
cargo container. Securement devices engageable with the locking openings 
in each of the corresponding housings in the top of the first container 
and the bottom of the second container secure the second container on the 
first container. 
SUMMARY OF THE INVENTION 
The present invention provides a container stacking apparatus for use in 
supporting at least one cargo container, and preferably two cargo 
containers, in double stacked relation on at least one other cargo 
container. 
An object of the present invention is the provision of a container stacking 
apparatus which facilitates the efficient transport of relatively shorter 
cargo containers by rail. 
Another object of the present invention is the provision of a container 
stacking apparatus for use in the stacking of at least three cargo 
containers on a railway car, the stacking apparatus including means for 
releaseably locking a frame down on one container, and means for 
releaseably locking a pair of containers down on the frame and in double 
stacked relation to the one container. 
Another object of the present invention is the provision of a container 
stacking apparatus for securing on top of at least one first container 
having a first arrangement of housings, at least one second container 
having a second arrangement of housings which does not match the first 
arrangement of housings. 
The container stacking apparatus includes a frame adapted to be supported 
on a first or lower container. The frame includes means for releaseably 
locking the frame down on the lower container, the means for releaseably 
locking including at least one first locking member having utility for 
restraining horizontal and upward movement of the frame relative to the 
lower container. The first locking member is positioned on the frame in 
alignment with a first opening or socket in a housing on the upper surface 
of the lower container. The first locking member is received in the first 
opening or socket when the frame is placed on the lower container to 
secure the frame to the lower container. 
The frame also includes means for releaseably locking at least one second 
or upper cargo container down on the frame and in double stacked relation 
to the first cargo container. The means for releaseably locking the at 
least one upper cargo container down on the frame includes at least one 
second locking member having utility for restraining horizontal and upward 
movement of the upper cargo container relative to the frame. The second 
locking member is positioned on the frame in alignment with a second 
opening or socket in a housing on the lower surface of the upper 
container. The second locking member is received in the second opening or 
socket when the upper container is placed on the frame to secure the upper 
container to the frame. 
Other features and advantages of the invention will become apparent to 
those skilled in the art upon review of the following detailed 
description, claims, and drawings.

Before one embodiment of the invention is explained in detail, it is to be 
understood that the invention is not limited in its application to the 
details of the construction and the arrangements of components set forth 
in the following description or illustrated in the drawings. The invention 
is capable of other embodiments and of being practiced or being carried 
out in various ways. Also, it is to be understood that the phraseology and 
terminology used herein is for the purpose of description and should not 
be regarded as limiting. 
GENERAL DESCRIPTION 
FIG. 1 illustrates a cargo container stacking arrangement 10 which is 
supported on a railroad car 12 and which embodies the invention. The 
railroad car 12 is preferably of a type known as a well car and includes a 
cargo container receiving well 14 which is defined by a support surface or 
floor 16, a front bulkhead wall 18, a rear bulkhead wall 20, and a pair of 
opposite sidewalls 22 and 24. Railroad wheels 26 support the well car 12 
for movement along a track 28. 
While in the illustrated arrangement, the cargo cobtainer stacking 
arrangement 10 is supported on a railroad well car 12 for transport, it is 
to be understood that the cargo container stacking arrangement 10 could be 
supported on other means of transportation of even on the ground. 
As shown in FIG. 1, the cargo container stacking arrangement 10 comprising 
a lower tier including a first or lower cargo container 30, an upper tier 
including a pair of second or upper cargo containers 32 and 34 positioned 
end to end and in cantilevered relation on the first cargo container 30, 
and a container stacking apparatus 36 for securing the upper containers 32 
and 34 in vertical or double stacked relation on the lower container 30. 
The lower container 30 fits into the well car well 14 and is supported on 
pads (not shown) which are located on the well car floor 16. When the 
container stacking apparatus 36 is lowered onto the lower container 30, 
the container stacking apparatus 36 is automatically secured in place on 
the lower container 30. Similarly, the upper containers 32 and 34 are 
automatically secured in place on the container stacking apparatus 36 when 
lowered thereon in stacked relation to the lower container 30, as will be 
further explained below. 
The container stacking apparatus 36 can be adapted to secure various sizes 
of containers in double stacked relation and it si to be understood that 
the containers 30, 32 and 34 can be of a standard or nonstandard size. The 
lower container 30 is preferably of a standard 40, 45 or 48 feet length 
and in the illustrated arrangement is shown as being 48 feet long. Each of 
the upper containers 32 and 34 is preferably 24 or 28 feet long, and in 
the illustrated arrangement the upper containers 32 and 34 are each 
nonstandard 28 feet length containers. 
As shown in the drawings, each of the cargo containers 30, 32 and 34 is 
generally box-like in appearance and includes a top, a bottom, opposite 
sides and opposite front and rear ends. Referring to FIG. 2, each of the 
lower cargo container 30 and the upper cargo containers 32 and 34 is 
provided with means, such as a set of doors 38, through which cargo can be 
loaded and unloaded. The doors 38 are preferably located at the rear end 
of each of the cargo containers 30, 32 and 34 and include hinges 40 and 
locking bar assemblies 42 for opening and closing the doors 38. Each of 
the containers 30, 32 and 34 can also include conventional means for 
facilitating over-the-road use so that the containers 30, 32 and 34 can be 
hauled individually or in tandem in a standard tractor trailer 
arrangement. An example of such means includes a channel 44 for receiving 
a chassis (not shown) which is attachable to a tractor. 
Each of the containers 30, 32 and 34 includes a plurality of standard 
castings or housings 48 which are used in securing the containers in 
double stacked relation. While the housings 48 in the lower container 30 
can be located in various positions, in the illustrated arrangement, the 
housings 48 are positioned in a first arrangement with a housing 48 
located longitudinally inwardly from each of the four corners in the upper 
surface 50 of the lower container 30. The first arrangement corresponds to 
the arrangement of housings 48 in standard 40, 45 or 48 feet length 
containers. FIG. 4 shows the arrangement of housings 48 in the upper 
surface 50 of the lower container 30. Similarly, while the housings 48 in 
each of the upper containers 32 and 34 can be located in various 
positions, in the illustrated arrangement, the housings 48 in each of the 
upper containers 32 and 34 are positioned in a second arrangement in the 
respective lower surfaces 52 and 54. The second arrangement includes 
housings 48 at each of the two corners at one end, and also at locations 
spaced longitudinally inwardly from each of the two corners at the other 
end of each of the lower surfaces 52 and 54. FIG. 3 shows the positioning 
of housings 48 in the lower surface 52 of the upper container 32. Although 
not shown, the lower surface of the lower container 30 and the upper 
surfaces of the upper containers 32 and 34 are also typically provided 
with housings 48. 
As shown in FIG. 6, each of the housings 48 includes an outer horizontal 
surface 56 which faces upwardly if the housing 48 is in the upper surface 
50 of the lower container 30, and downwardly if the housing 48 is located 
in one of the lower surfaces 52 and 54 of the upper containers 32 and 34. 
A noncircular locking hole or opening 60 in the outer surface 56 
communicates with a housing socket 62 (See FIG. 7) which is defined by an 
inner socket surface 64 and which extends either upwardly or downwardly 
from the locking opening 60. The locking opening 60 is defined by an outer 
perimeter or edge 66 in the outer surface 56 and an inner perimeter or 
edge 68 in the inner socket surface 64. Each of the housings 48 is 
preferably of a type specified in the standards of the Association of 
American Railroads, in which case additional openings (not shown) are 
included. 
The container stacking apparatus 36 is provided to support the upper cargo 
containers 32 and 34 in doubled stacked relation on the lower container 
30. While in the illustrated arrangement the container stacking apparatus 
36 supports a pair of upper containers 32 and 34 in double stacked 
relation on a single lower container 30, in other arrangements, the 
container stacking apparatus 36 can support one or more upper containers 
in double stacked relation on one or more lower containers. 
As shown in FIG. 3, the container stacking apparatus 36 includes an 
elongated frame 70 which fits on the lower container 30. Components of the 
frame 70 are secured together by suitable means such as welding. The frame 
70 includes a pair of substantially parallel and preferably identical main 
beam assemblies 72 and 74. The main beam assemblies 72 and 74 are spaced 
apart from each other so that each of the containers 30, 32 and 34 fits 
therebetween. Each of the main beam assemblies 72 and 74 includes a top 
flange 76, a bottom flange 78, and a web 80 interconnecting the top flange 
76 and the bottom flange 78 to form an I shape (FIG. 14). 
As shown in FIG. 15, the opposite ends of each of the main beam assemblies 
72 and 74 preferably includes a box beam assembly 82 having a pair 
complimentary box beam members 84 and 86 extending between the top flange 
76 and the bottom flange 78, and also from the end of the web 80 to the 
ends of the flanges 76 and 78. Each of the box beam assemblies 82 provides 
additional rigidity and strength to the ends of the main beam assemblies 
72 and 74. Stiffeners 88 are provided at various locations in each box 
beam assembly 82. 
The frame 70 includes a pair of elongated tubular end crossmembers 92 and 
94 interconnecting the ends of the main beam assemblies 72 and 74 to form 
a generally rectangular structure. As shown in FIG. 16 with respect to end 
crossmember 92, each of the end crossmembers 92 and 94 includes a 
downwardly slanted surface 96 which can serve as a guide to assist in 
positioning the frame 70 on top of the lower container 30. 
As shown in FIG. 10, the frame 70 also includes an elongated midspan 
crossmember 98 interconnecting the midsections of the main beam assemblies 
72 and 74. The midspan crossmember 98 includes opposite outwardly and 
upwardly facing slanted surfaces 100 and 102 which can serve as guides to 
assist in positioning the upper containers 32 and 34 on the frame 70 so 
that the midspan crossmember 98 separates the upper containers 32 and 34 
from each other. An I-beam member 104 extending beneath the midspan 
crossmember 98 and between the main beam assemblies 72 and 74 supports the 
midspan crossmember 98. 
The frame 70 is provided with means for supporting the frame 70 on the 
lower container 30. In the illustrated arrangement, the means for 
supporting the frame 70 on the lower container 30 includes four 
substantially horizontal, coplanar first plates 106. Each of the first 
plates 106 is secured along one side to one of the main beam assemblies 72 
and 74 and is positioned to extend over one of the housings 48 in the 
upper surface 50 when the frame 70 is placed on the lower container 30. As 
shown in FIG. 17, each of the first plates 106 is supported by a pair of 
upwardly extending gusset members 107 and a downwardly extending gusset 
member 109 each secured to one of the main beam assemblies 72 and 74. 
The frame 70 also includes means for supporting the upper containers 32 and 
34 thereon. While various means for supporting the upper containers 32 and 
34 can be employed, in the illustrated arrangement, the supporting means 
includes a plurality of substantially horizontal, coplanar second plates 
including a pair of preferably hexagonally shaped midspan plates 110. Each 
of the midspan plates 110 is secured along one side to one of the main 
beam assemblies 72 and 74 and engages the underside of the midspan 
crossmember 98. The midspan plates 110 respectively extend beneath one of 
the housings 48 in each of the lower surfaces 52 and 54 when the upper 
containers 32 and 34 are placed on the frame 70. Each of the midspan 
plates 110 is provided with a pair of upwardly extending midspan gusset 
members 112, and three downwardly extending midspan gusset members 114. 
The midspan gusset members 112 and 114 are each secured to one of the main 
beam assemblies 72 and 74 and provide added support to the midspan plates 
110. 
The means for supporting the upper containers 32 and 34 on the frame 70 
also includes end or corner plates 116. The corner plates 116 are 
positioned at each of the four intersections of the end crossmembers 92 
and 94 and the main beam assemblies 72 and 74. Each of the corner plates 
116 is secured along one side to one of the main beam assemblies 72 and 74 
with the lower surface of each of the corner plates 116 engaging the top 
side of one of the end crossmembers 92 and 94. Each of the corner plates 
116 extends beneath one of the housings 48 in one of the lower surfaces 52 
and 54 when the upper container 32 and 34 are placed on the frame 70. An 
upwardly extending end gusset member 118 extends upwardly from each corner 
plate 116 for added support. 
As shown in FIGS. 18, 19 and 20, each of the upwardly extending gusset 
members 107, 112 and 118 includes an upwardly facing slanted surface 120 
which can act as a guide in positioning one of the upper containers 32 and 
34 in its proper position on the frame 70. Additionally, each of the 
downwardly extending gusset members 108 and 114 includes a downwardly 
facing slanted surface 122 which can act as a guide in positioning the 
frame 70 in its proper position on the lower container 30. 
The frame 70 includes a plurality of locking members 124. The locking 
members 124 include a set of first locking members 124A for releaseably 
securing the frame 70 down on the lower container 30. Each of the first 
locking members 124A is secured to one of the first plates 106 and extends 
downwardly therefrom. Each of the first locking members 124A is aligned 
with and corresponds to one of the housings 48 in the lower container 30. 
The locking members 124 also include a set of second locking members 124B 
for releaseably locking the upper containers 32 and 34 down on the frame 
70. Each of the second locking members 124B is secured to one of the 
midspan plates 110 or the corner plates 116 and extends upwardly 
therefrom. Each of the second locking members 124B is aligned with and 
corresponds to one of the housings 48 in the upper containers 32 and 34. 
It is to be understood that the positions of the first plates 106, the 
midspan plates 110, and the corner plates 116 can be varied to change the 
positions of the first and second locking members 124A and 124B to 
accommodate upper and lower containers having any of various housing 
arrangements. 
While various configurations of locking members 124 can be employed, in the 
illustrated arrangement the locking members 124 are preferably of the type 
disclosed in U.S. Pat. No. 4,626,155, issued Dec. 12, 1986, to Hlinsky et 
al, and the disclosure of which is herein incorporated by reference. 
FIG. 9 illustrates engagement of a locking member 124 with a housing 48 to 
releaseably lock the locking member 124 within the housings 48. As shown 
in FIG. 9, the locking member 124 includes a base 126 adapted to be 
secured to one of the first plates 106, the midspan plates 110, or the 
corner plates 116. A head 128 is pivotally mounted on a shear block 130 
which projects from the base 126. The head 128 is pivotable between a 
locked position (shown in solid lines in FIG. 8) and a loading position 
(shown in broken lines in FIG. 8). A torsional spring (not shown) is 
provided to bias the head 128 to the locked position. 
To facilitate entry of the head 128 into the housing 48 the head 128 is 
provided with a first cam surface 132 which is configured to interact with 
the outer edge 66 of the locking opening 60. Engagement of the first cam 
surface 132 with the outer edge 66 pivots the head 128 to the loading 
position when an entry force is applied. This permits movement of the head 
128 through the locking opening 60 and into the socket 62. When the head 
128 extends fully into the socket 62, the head 128 is returned to the 
locking position by the torsional spring to secure the locking member 124 
within the housing 48. The shear block 130 is received in the locking 
opening 60 to prevent horizontal movement in any direction of the locking 
member 124 and housing 48 relative to one another. 
To facilitate removal of the locking member 124 from the housing 48, the 
head 128 is provided with a second cam surface 134. The second cam surface 
134 is configured to interact with the inner edge 68 of the locking 
opening 60 to rotate the head from the locked position to the loading 
position when an exit force is applied. The exit force is preferably 
substantially greater than the entry force so that automatic unlocking and 
release of the locking member 124 from the housing 48 is substantially 
more difficult than automatic locking of the locking member 124 within the 
housing 48, as explained in the aforementioned U.S. Pat. No. 4,626,155. 
To load the upper containers 32 and 34 in double stacked relation on the 
lower container 30, the frame 70 is lowered on to the lower container 30 
so that the first locking members 124A engage the locking openings 60 of 
the corresponding housings 48 in the upper surface 50. The weight of the 
frame 70 provides a first force preferably greater than the combined entry 
forces required to automatically lock the first locking members 124A 
within their corresponding housings 48 in the lower container 30. The 
heads 128 and shear blocks 130 of the first locking members 124A 
respectively lock the frame 70 down on the lower container 30 and restrain 
horizontal movement of the frame 70 relative to the lower container 30. 
Before or after the frame 70 is lowered on to the lower container 30, each 
of the upper containers 32 and 34 is individually lowered on to the frame 
70 so that the second locking members 124B engage the locking openings 60 
of the corresponding housings 48 in the upper containers 32 and 34. The 
empty weight of each of the upper containers 32 and 34 is preferably 
sufficient to provide the combined entry forces required to automatically 
lock the second locking members 124B within their corresponding housings 
48 in the upper containers 32 and 34. The heads 128 and shear blocks 130 
of the second locking members 124B respectively lock the upper containers 
32 and 34 down on the frame 70 and restrain horizontal movement of the 
upper containers 32 and 34 relative to the frame 70. 
To unload containers 30, 32 and 34, a conventional straddle lift or other 
device can be used to individually lift the upper containers 32 and 34 
from the frame 70. The exit forces required to automatically release the 
upper containers 32 and 34 from the frame 70 are provided by the straddle 
lift. The straddle lift can be used in a similar fashion to remove the 
frame 70 from the upper container. 
The frame 70 is provided with four top lift or straddle lift assemblies 
136. A straddle lift assembly 136 is positioned at each of two locations 
on each of the main beam assemblies 72 and 74. As shown in FIG. 13, each 
of the straddle lift assemblies 136 includes four spaced apart channel 
reinforcements 138 secured to the inside of one of the main beam 
assemblies 72 and 74. Each of the straddle lift assemblies 136 also 
includes a lifting bar or plate 140 extending outwardly from the bottom of 
flange 78. The lifting plate 140 and bottom surface of flange 78 together 
form a generally horizontal lifting surface. Each of the straddle lift 
assemblies 136 also includes a cap member 142 angling between the lifting 
plate 140 and the web 80, and a plurality of triangular members 143. The 
cap member 140 and the triangular members 143 cooperate to transmit 
lifting forces on the straddle lift assembly 136 to one of the main beam 
assemblies 72 and 74. D-rings 144 are also provided to facilitate lifting 
the frame 70 by means such as chains or the like. 
The frame 70 is provided with leg channels 146 which have enlarged tops and 
narrowed bottoms to facilitate the stacking of a number of frames 70 on 
top of one another. In stacking the frames 70 for storage or transport, 
the narrowed bottoms of the leg channels 146 of a first or upper frame are 
inserted into the enlarged tops of the leg channels 146 of a second or 
lower frame to stack the frames. 
One of the advantages of the container stacking apparatus 36 is that it 
enables a pair of relatively shorter upper containers 32 and 34 to be 
transported by rail on a relatively longer lower container 30 to more 
efficiently transport the shorter containers. The double stacking of a 
pair of relatively shorter upper containers 32 and 34 on a lower container 
30 allows the railroads to be more competitive in the less than truckload 
market. p Various features of the invention are set forth in the following 
claims.