US 3561633 A
Description (OCR text may contain errors)
United States Patent  Inventors Robert S. Morrison  References Cited UNITED STATES PATENTS Ashtabula;
575 3 w n b B mmw wm m. 0 2 2 2 2 2 2 2 man mm 0 Hum "mm n m &e h .n&m m wm m m 13%M ME KHFVTC S 902288 7 566666 6 999999 9 HHHHHH N 790255 9 11 34 84 5 7 3090 5 6 723 4 956688 4 4 223333 .m h 0 e n n m a .w m d c w J or n W w 0 f m M R 0 7'- 6 P w nha d m m n n W a ."mrg 3 m M7JFMAa. 0. e N mm ll Hg 0 P .1 p mmx AFPA 11]] 253 UUHW Primary Examiner-George E. Lowrance  CONTAINER 12 Claims 11 Drawing-Figs Attorney-Oberlin, Maky, Donnelly & Renner m d GO .lOn w C ml m w m dbm nec
mm f ABSTRACT: A container for general ca eluding an extruded metallic frame havin or like material encapsulated with glass r bonded with a polyurethane adhesive be adjacent panels to form a monolithic boxlike structure.
PATENTED FEB 915m SHEET 3 OF 4 mul INVENTORS ROBERT 5. MORRISON EDWARD P REBOV/CH 0 BY ywl flmd wflww v ATTURNI-IYS CONTAINER This invention relates generally as indicated to a container and more particularly to a lightweight yet strong container which can very easily be fabricated.
Containerization for the movement of general cargo in the transportation industry is becoming more widely used. Containers used for such purposes should desirably be as lightweight as possible since they do not constitute a pay load but must be of necessity have sufficient strength to be supported by cranes, fork lift trucks, and the like as well as being subject to the abuse and weather conditions inherent in the transportation industry. The container must also act as a deterrent to pilfering.
Heretofore such containers have required heavy duty frames permitting the container to be lifted from the top or the bottom and also serving to support the panels. The panels have generally acted simply as frame closures and have contributed little to the structural strength of the container.
It is accordingly a principal object of the present invention to provide a lightweight yet stronger container.
Another important object is the provision of a container utilizing a lightweight frame having bonded thereto panels of plywood encapsulated in a fibrous glass reinforced plastic.
A further important object is the provision of a monolithic container wherein the panels as well as the frame contribute substantially to the structural integrity.
Another object is the provision of such stronger yet lighter box which can very economically be fabricated.
A further object is the provision of such container utilizing an adhesive such as polyurethane rather than conventional fasteners, such adhesive having approximately 50 or more percent elongation without fatigue.
A still further object is the provision of such container which can utilize bonded panels of standard size thus avoiding costly special dies.
Other objects and advantages of the present invention will become apparent as thefollowing description proceeds.
To the accomplishment of the foregoing and related ends, the invention, then, comprises the features hereinafter fully described and particularly pointed out in the claims, the following description and the annexed drawings setting forth in detail a certain illustrative embodiment of the invention, this being indicative, however, of but one of the various ways in which the principles of the invention may be employed.
In said annexed drawings:
FIG. I is a perspective view of a container in accordance with the present invention with the rear of the container being shown open and the doors removed;
FIG. 2 is a partial exploded view of the container of FIG. 1 showing one side panel, the front panel and the roof panel;
FIG. 3 is a fragmentary horizontal section taken substantially on the line 3-3 of FIGS. 1 or 2 showing the bonded joint between adjacent panels;
FIG. 4 is an enlarged fragmentary vertical section taken substantially on the line 44 of FIG. 2 illustrating a fork lift truck pocket in the floor frame;
FIG. 5 is an enlarged fragmentary horizontal section through the frame post at the rear of the container as taken substantially on the line 5-5 of FIG. 1;
FIG. 6 is a fragmentary horizontal section through a forward comer post as taken substantially on the line 6-6 of FIG. 1;
FIG. 7 is an enlarged vertical fragmentary section showing the edge of the sill as taken substantially from the line 7-7 of FIG. 4;
FIG. 8 is a fragmentary enlarged end elevation of the container showing the detail of a door which may be hingedly connected in the rear opening;
FIG. 9 is an enlarged fragmentary vertical section taken through the top of the rear opening substantially on the line 9-9 of FIG. 8;
FIG. 10 is a fragmentary horizontal section taken substantially on the line 10-10 of FIG. 8; and
FIG. 11 is a fragmentary vertical section through the bottom of the opening taken substantially on the line I 1-1 I of FIG. 8.
Referring now to the annexed drawings and more particularly to FIGS. 1 and 2, it will be seen that the illustrated container I0 principally comprises a metallic frame 11 and panels 12, the latter including a roof panel 13, side panels 14 and I5.
5 a front panel 16 and a floor 17. Each of the panels 13 through 16 as well as the floor 17 may be made up of standard size panels 19 joined in butting fashion to form the enlarged side, end, roof and floor panels indicated. As seen more clearly in FIG. 2, the end panel of each of such enlarged panels may have its corner cut away as seen at 20 to accommodate top comer blocks 21, 22, 23 and 24 as well as the bottom or sill comer blocks 25, 26, 27 and 28 of the frame II.
The individual panels 19, as seen in greater detail in FIG. 3, may each include a core 30 of suitable marine grade plywood or like material encapsulated in a fibrous glass reinforced polyester resin as seen at 31. Such panels may be made in matched metal dies as seen more clearly in the copending application of Robert S. Morrison. Ser. No. 727,808, filed May 9, I968 entitled Fibrous Glass Plastic Encapsulated Plywood Panel and Method of Making Same. The individual standard size panels are joined as indicated in FIG. 3 utilizing a polyurcthane adhesive bond having an elongation on the order of 50 to 60 percent without fatigue. Metallic bond strips 32 and 33 bridge the vertical edges of the faces of the panels 19. In perfccting such bond, the bond strips may be spaced from the panel faces something on the order of 0.020 inch to allow sufficient bond thickness. This spacing may be obtained by placing wires of known dimension on the panel face before the adhesive application of the bond strips. Such bond strips, if aluminum, may be on the order of 0.032 inch thick. If steel, the thickness may be on the order of 0.015 inch. A neoprene or like material tape seal 35 may be positioned between the adjoining end faces of the panel to ensure a weathertight joint. The entire joint as indicated may be adhesively bonded with the aforementioned polyurethane.
It can thus be seen that the standard size panels may serve as a module and be bonded together to form panels of really any desired size. Panels bonded with the joint shown in FIG. 3 become a substantially monolithic structure. The bond strips form the flanges of an integral I-beam thus transfonning a single panel into a bridge structure which eliminates stress concentration. As a result, greater loads with less deflection are made possible. Also, because the polyurethane bond has approximately 50 or 60 percent elongation without fatigue, the panel can withstand either shock loads or continuous loads indefinitely without adhesive deterioration. The bonded panels allow the use of standard size panels thus eliminating the need for a variety of sizes of costly dies.
The but joint illustrated in FIG. 3 is utilized only with the side panels 14 and 15, the roof panel 13 and the front panel 16. With the floor panel 17 no bond strips need be employed since the individual panels 19 of the floor 17 are bonded by the aforementioned polyurethane adhesive directly to the floor frame members as indicated in FIGS. 2 and 4. The same polyurethane adhesive bond will be used to secure all of the panels to the metallic frame toform a monolithic box structure in which the panels themselves become substantial structural elements.
Referring now more particularly to FIG. 2, it will be seen that the frame 11, in addition to the corner blocks 21 through 28, includes a number of extrusions welded to and secured between such blocks forming the frame structure. Commencing with the floor frame shown generally at side sill extrusions 41 and 42 are secured between the blocks 26 and 28, and 25 and 27, respectively. These side sill extrusions are shown in greater detail in FIG. 7 and are identical in form. The same extrusion extends between the corner blocks 25 and 26 at the front of the container as seen at 43. A Z-shape transverse frame member 44 extends between the comer blocks 27 and 28 at the rear of the floor frame 40. The detail of the frame member 44 may be seen more clearly in FIG. 11.
Also extending between the side sill extrusions 41 and 42 are two I-beams 4S and 46 and four fork truck pocket weldments 47, 48, 49 and 50, the details of which are seen in FIG. 4. The opposite ends of such weldments communicate with apertures 52, 53, 54 and 55 in each side sill so that the forks or prongs of a lift truck may readily be inserted therein and the container lifted. It is also here noted that the corner blocks are provided with apertures seen more clearly in FIG. 2 at 56 into which may be placed the hooks of cargo slings so that the container may readily be lifted by crane from flat car or truck to ship and vice versa, etc.
As seen in FIG. 4, each weldment includes an inverted wide U-shape channel 58 having a planar top surface 59. To the underside of the channel there is secured a reinforcing plate 60 against which the fork of the lift truck bears. Exteriorly of the legs 61 and 62 of the channel 58 there is secured additional channels 63 and 64 with the web of each outer channel abutting the leg of the center channel 58. The top surfaces 66 and 67 of the outer smaller channels 63 and 64 are flat and coplanar with the flat top surface 59 of the center channel.
Referring to FIG. 7, it will be seen that the fork lift truck pockets as well as the l-beams fit between the inwardly extending flanges 68 and 69 of the side sill extrusions 41 and 42. The transverse frame members may be recessed at their upper lateral edges as indicated at 70 to accommodate the top flanges 68. Such top flanges include two beads shown at 71 an 172 which guarantee a spacing of approximately 0.020 inch between the underside of the floor panel 17 and the top surface 73 of the flange 68. The top surface of the transverse structural members of the sill seen at 74 is coplanar with the surface 73. Again, during construction, wires having a diameter of approximately such 0.020 inch may be laid on the sur' face 74 to obtain the desired spacing for the adhesive which will then bond the underside of the floor panel 17 to the top planar metallic surfaces of the sill or floor frame 40. The transverse structural frame members may be welded interiorly of the lower sills 41 and 42 completely within the two flanges and adjacent the main vertical wall as seen at 75.
In addition to the two inwardly directed flanges 68 and 69, the lower sill extrusion 41 is also provided with the two upstanding flanges 77 and 78, each of which is provided with inwardly directed vertically spaced beads seen at 79 and 80, again which guarantees approximately 0.020 inch thickness for the adhesive bond which secures the side panel 15 to the sill extrusion 41.
The front panel 16 and the side panel 14 will be secured to the front sill extrusion 43 and the side sill extrusion 42, respectively, in the same manner.
Referring again to FIGS. 1 and 2, it will be seen that the metal frame 11 includes a rear door extrusion, three lengths of which are provided as indicated at 83, 84 and extending respectively between the lower comer block 28 and the upper comer block 24, the two upper rear comer blocks 24 and 23, and the upper rear comer block 23 and the lower comer block 27. The detail of these extrusions is seen more clearly in FIGS. 5, 9 and 10. Each rear door extrusion includes a square tubular portion 87. Extending rearwardly from the outer wall 88 thereof is an enlarged flange 89 of the same wall thickness as the tubular portion which has an inwardly curved outer edge 90. Extending forwardly are laterally spaced flanges 91 and 92, the former being flush with the outer wall 88 of the tubular portion 87. Such flanges have inwardly directed spaced beads as seen at 93 and 94 which serve to provide the aforementinned 0.020 inch spacing between the sidewall panel and the extrusion flanges to accommodate the polyurethane bond. The extrusion lengths 83-85 are identical in form.
Referring again to FIGS. 1 and 2, there is provided a third type of extrusion which may be termed a corner extrusion which is seen in greater detail in FIG. 6. Such corner extrusion extends along the top edges of the roof panel 13 as well as the side panels 14 and 15 as seen at 96 and 97 joining the upper comer blocks 21-23 and 22-24, respectively. A corner extrusion also extends along the upper front edge of the container as seen at 98 joining the front top corner blocks 21 and 22. Corner extrusions 99 and 100 extend between the blocks 21 and 25, and 22 and 26, respcctivelygjoining the side panels with the front panel 16.
Referring to FIG. 6, it will be seen that each corner extrusion includes a substantially square tubular corner portion 102, the outer corner of which is rounded as seen at 103. From the inner corner there project normal to each other flanges 104 and 105 which are paired with parallel flanges 106 and 107, respectively. The flanges are spaced the same as the opposite wall portions of the tubular portion 102 so that the outer flanges 106 and 107 are flush with the outer surface of the extrusion. Each set of flanges has inwardlydirected beads as indicatcd at 108 and 109 ensuring the aforementioned proper spacing to accommodate the adhesive bond between the panels and the inner surface of the flanges.
Referring now to FIGS. 8, 9, 10 and 11, it will be seen that the door panels 110, only one of two being shown in FIG. 8. may be hingcdly connected to the vertical extrusions 83 and 85. As indicated, fourvertically spaced hinges 111 are provided and the rearwardly extending flange 89 may be cut away as indicated at 112 to accommodate such hinge. Such hinge includes a hinge pin 113 extending between vertically spaced fixed knuckles 114 and-l15. Such pin extends through the hinge leaf knuckle 116 which is outwardly offset from the leaf 117. The leaf is secured to the door panel by suitable fasteners seen at 118.
A latching rod 120 extending through latch brackets 121, 122 and 123 operated in conventional manner by handle 124 is also provided on such door.
The door panel, like the other panels of the container. is preferably made of marine grade plywood or the like which is encapsulated in a fibrous glass reinforced plastic such as polyester. Again, reference may be had to the aforementioned copending application of Robert S. Morrison for a more detailed disclosure of such panel.
To accommodate the various fasteners shown, holes are predrilled in the plywood and then molded'solid with the polyester resin. The holes are then postdrilled with a smaller drill so that a completely encapsulated hole is obtained to accommodate the fasteners. In this manner no moisture gets into the plywood through the hole and the area around the hole has much greater compressive strength because of the solid polyester. If holes are positioned close to the edge of the panel, the combination of the encapsulated hole and the en capsulated edge results in a much greater resistance to pullingout of the fastener.
Because of the very high compression strength of the reinforced plastic encapsulated plywood, the door panels can actually be made to be a shear wall of the container limiting flexure. As seen in FIGS. 9, 10 and 11, a slight clearance is provided at 126 between the top door extrusion 84 and the panel 110 which may be closed by a flexible seal 127. A similar clearance and seal is provided along the lateral edges of the door as indicated at 128 in FIG. 10 and a deformable seal 129 is provided along the bottom edge of thedoor as seen in FIG. 11. With the door closed and the container subject to lateral loads or twisting, the door panel 110 will bear against the inner wall 130 or 131 of the door extrusions 83 or 84 as seen floor frame 40 including the side end and sills and the four comer blocks. The fork lift pockets and the l-beams are then positioned between the side sills. Next, the front panel subassembly is assembled with the panel and cornerposts 99 and 100. Then the two side subassemblies are provided which in" clude the side panels and the rear corner or doorposts 83 and 85. Next there is provided a roof subassembly which includes the roof panel 13, roof side rails 96 and 97, and the roof end rails 98 and 84. With these subassemblies, the floor frame and side subassemblies are then connected followed by the front subassembly. Finally the roof subassembly is positioned in place. The floor panels 17 are then adhesively secured to the top of the floor frame and finally the door and latching hardware is secured in place.
Although the aforementioned polyurethane elastomeric adhesives are preferred, it will be appreciated that any bonding or adhesive material having approximately 50 to 60 percent elongation without fatigue will suffice. One suitable example of an adhesive is that polyurethane elastomeric adhesive sold under the trademark PLlOGRlP by the Goodyear Tire and Rubber Company of Akron, Ohio. Such elastomeric adhesives have a tensile strength in p.s.i. from about 2250 to 2520. an elongation factor of about 55 percent, a shore D hardness of from about 59 to 64 and a modulus at 50 percent elongation from about 2200 to 2330.
Such adhesives will cure at room temperatures, but, of course, the cure can be accelerated at elevated temperatures.
A wash solution may be applied by wiping, spraying or brushing on the polyester surfaces of the panels and this acts as a degreasing and cleaning agent while at the same time increasing the wettability and the activity of the plastic surface. The wash solution may deposit a monomolecular layer of highly polar reactive sites on the surface of the substrate which insures the proper bonding of the adhesive thereto. Various types of wash solutions may be employed and cleaning with methylene chloride may be satisfactory.
A metal primer for the metallic frame may be employed insuring a positive bond as well as protecting the substrate under corrosive conditions. The metal primer may be dipped, rolled, sprayed or brushed on the metal surface. The primer should then be dried to remove the solvents with the result being a nontacky primer film.
The beads on the metal extrusions ensure the proper thickness of the elastomeric adhesive bond and wires of the same diameter may be laid on other metallic surfaces to insure such uniform thickness of the adhesive. The strong bond is formed by the chemical reaction of the several components of the adhesive which forms a highly cross-linked polymer, in situ. The elastomeric nature of the adhesive constitutes an energy absorbing system which provides a monolithic structure making each of the panels an integral structural part of the container. Such polyurethane elastomeric adhesives are generally two-part systems and start curing as soon as the base adhesive is mixed with any of the curing agents employed.
Fundamentally the chemistry of a polyurethane system involves the reaction of polyhydroxyl materials, such as polyesters, polyethers, etc. with isocyanates to yield a solid elastomeric product which has the aforementioned adhesive properties.
It can now be seen that there is provided a container highly suitable for general cargo which comprises a lightweight monolithic structure. The container may, of course, be used as a truck or railroad car body. The metallic frame comprises relatively few metallic extrusions with panels being bonded to each other and to such frame providing a monolithic structure wherein the panels contribute substantially to the structure as a whole. Steel or aluminum can, of course, be used for the frame. Not only is the container lighter than conventional containers, but can economically be produced.
Other modes of applying the principles of the invention may be employed, change being made as regards the details described, provided the features stated in any ofthc following claims or the equivalent of such be employed.
1. An intermodal freight container comprising a metallic frame, and panels adhesivcly bonded to said frame, each panel comprising a core of plywood and the like encapsulated in a fibrous glass reinforced plastic, said adhesive bond having limited elasticity to permit flexure of the total system while retaining its integrity.
2. A container as set forth in claim l including a polyurethane adhesive bonding said panels to each other and said frame.
3. A container as set forth in claim 2 including a butt joint between adjacent panels with thin metallic bond strips covering such butt joint and bonded by such adhesive to the faces of adjacent panels.
4. A container as set forth in claim 1 including an elastomeric adhesive bonding said panels to each other and said frame. said adhesive having about 50 to 60 percent elongation without fatigue.
5. A container as set forth in claim 1 wherein said frame includes extrusions having parallel flanges adapted to receive therebetween the edges of said panels.
6. A container as set forth in claim 1 wherein said frame includes extrusions having parallel flanges adapted to receive the edges of said panels, and beads on the interior of said flanges adapted to ensure a predetermined bond thickness.
7. A container as set forth in claim 1 wherein said frame includes a floor frame having transverse fork truck pockets, the floor panel of said container being bonded to the top surface of said pockets.
8. A container as set forth in claim 1 including a door at one end of said container, said door including panels hinged to said frame and fitting closely therein, said door panels each comprising a core of plywood and the like encapsulated in fibrous glass reinforced plastic.
9. A container as set forth in claim 1 wherein said metallic frame includes a comer extrusion, a sill extrusion, and a door frame extrusion, each extrusion including parallel flanges adapted to receive the edges of said panels.
l0. A container as set forth in claim 1 wherein said metallic frame includes a floor frame having a lower sill extrusion at the lateral and forward edges thereof, said lower sill extrusion including upstanding parallel flanges adapted to receive the side and forward panels of said container, said lower sill extrusion also including inwardly directed vertically spaced flanges between which transverse floor frame members are secured.
11. A container as set forth in claim 1 wherein said panels each comprise a multiple of standard size panels butt joined together.
12. A container as set forth in claim 1 including an elastomeric adhesive bonding said panels to each other and said frame, said adhesive being of a thickness on the order of 0.020 inch.