CA1187130A - Vertically adjustable loading deck for transport containers - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE
A trailer container deck support system consisting of a plurality of units, each unit having a vertical channel on opposing side walls of the container, an elongated member slidably positioned within the channel, a bracket secured to the elongated member and a deck secured to the bracket so that the deck can be moved vertically within the trailer body within the confines dictated by the vertical channels.

Description

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This invention relates generally to containers for cargo transportation and storage, and more particularly, to a vertically acting cargo deck which may be quickly and easily disposed at a predetermiend vertical height above a fixed cargo deck or platform (i.e. floor) to increase the useful 102d capacity of a cargo transport or storage container.
The transportation of cargo has developed into an important industry. The trucking industry employs vans and semi-trailers which comprise closed cargo containers that are each provided with a fixed deck that functions as the bottom (i.e. floor) of the cargo container on which the full weight capacity of the container can be supported. The present type closed cargo containers are constructed with roof rail members and wall members which also have a capacity for supporting the ~ul~ welght capacity of the container. For example, many heavy loads of meat are often carried in closed cargo containers by supporting the same from overhead attachment means carried by the roof rail members. In many instances the cargo carried in a closed cargo container is of such a light weight nature that when the cargo is loaded onto the main deck (floor) of the container, the entire deck is covered, while neither the weight capacity of the container, nor the cubic capacity, is fully utilized.
Heretofore, in order to overcome the disadvantage of the last mentioned cargo situation, it has been proposed to provide a second loading deck (or decks) supported approximately one-half way up on the container walls to provide additional loading deck area~ One of such systems is to equip the side walls of the container with pre-punched angle or channel strips which will accept individual snap-in, load-supporting members. Such load-supporting members are then covered wlth decking material, such as plywood, to form an elevated deck which will double ~he cargo deck surface capacity of the trailer. In such a Gecond deck arrangement, there are many loose components and this is a disadvantage since it takes considerable time in handling said 3~

components ~o build up and load such a second deck, and to disassemble the same after each use. The last described prior art second deck arrangement has a further disadvantage of having many support members which must be handled several times, and the various deck components are subject to being lost, stolen or le~t behind by the operator of a semi-trailer. When not in use, the second deck components often are difficult to carry and take up usable cargo carrying space. To avoid such cargo space waste, the second deck components can be stored at a home dock terminal, but such a procedure provides a further disadvantage in that the second deck components are not available if it is necessary to make unexpected cargo pickups at remote destinations.
Another type of deck system is a two piece~unfolding frame supported off one wall (Vandegriff, U.S. Patent 911,832) to provide one height loading, but in the wall hanging storage position this system robs precious loading width (of approxmimately 5~). Further disadvantages are that:
(1) people can get fingers caught in folding and unfolding the frame;

(2) sliding load brackets sometimes disengage under load causing deck and cargo to fall; and

(3) panels are unwieldy for one person to handle.
A second variation of wall hung one piece deck has recessed wall panels, but the panels are heavy, tend to bind in the "storage mode", are aw~ward to assemble, and are of limited capacity. Also ~len the decks are in the horizontal (loading mode) position, the inner sidewall of the trailer is used to posleion the cargo and as there is no inner side liner protection there is nothing to prevent outer trailer skin damage occurring from inside cargo or fork li~t ~ction.
The vertically adjustahle loading deck for transport containers as disclosed in Canadian patene ~93,476 issued ~ebruary 22, 1972 to Thomas F.
Adams, discloses a system whi~h works well, has adjustable load heights, stores at the ceiling of the container, and is safe and easy to use. However, it is custom made for each type of trailer van 30 that 8 large inventory of replacement parts is required. Deck units Pabricated of wood are glued into a deck panel and fracture when hit by a eork lift truck, or when oYerloaded, and are normally not repairable but must be replaced.
Repair of this system also tends to be time consuming ns major disassembly is often required for replacement of fractured panels trolleys or guide tracks.
Althou~h decks move up and down easy, often fork lift drivers will use force to easily raise decks with the forks causing some damage. Items such as load brackets, hold down latches, etc. also protrude below the deck and restrict the cargo space underne~th. ~urthermore the adjustable height feature requires added h~rdware which must be installed and maintained, and Qdds cost and weightD thus subtracting from cargo payload. Also with an easily adjustable system there are six (6) tracks per deck with four (4) being used for loading height adjustm2nt. Each has l loadstop and four (4) stops must all be adjusted to the same hei~ht ~or each deck. Fsilure to do so causes strain and breakage of the deck and/or supportin~ hardware.
In view of the foregoing, it is an important object of the present invention to provide a novel and improved vertical acting loading deck for closed cargo containers such as van trailers, van trucks, railro~d cars or other containers which overcomes the disadvanta~es of the prior art second deck constructions and provides improvements to the system disclosed in Adams' patent 893,476 with respect to operation, universal adapt~tion and quick "in-trailer" maintenane and repair. A clear-spQn design is al50 provided with close fitting or recesssd hardware and this one lo~d helght prevents mishaps so that there is grester reliability and as there are fewer moving parts the initial cost is lower and ~reater payload can be handled with lower maintenance bein~ required. (No load height adjustment can be made, e~cept with tools and/or by removing fasteners).
The preferred embodiments of the invention wi11 now be described w;th reference to the accompanying drawings in which:
Figure l is a perspective view of a trailer, partly in cross-section showing the invention;
Figure 2 is a partial view inside the trailer of Figure l;
Figure 3 is a partial plan view of the trailer of Figure l;
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Figure 4 is an exploded ~iew of the latch mechsnism and its corporation with the sides of the trailer of Figure l;
Figure S is a perspective view of the deck as used in Pigure 1, partly in section;
Figure 6 is a perspective view of 8 deck ns used in the trailer of patent 893,476, partly sectioned &nd partly exploded showing interior load brack2ts only at four (4) corners of the deck with under support channel to support center ends;
Figure 7 is a dia~rs~matic view of a further embodiment of the invention showing interior tension springs;
Fi~ure 8 is ~ diagrammatic view of another embodiment of the invention showing a second type of torsion spring;
Figure 9 is a!further type of support system for the self storing dec~
bars and includes two enlarged details of various fittings; and Pigure 10 is a diagrammatic view of the mechanism utilized with self storing decking bars.
Referring specifically to the d~awings, in Figure l there is shown a container or trailer 1 having movable decks 3 positioned at various heights within the trail~r. The decks 3 are normally stor~d at the roof of the trailer and, in theîr lower position when used for supporting loads, rest upon a rail S which is riveted along both sides of the trailer body. Figures ~, 3 and 4 show the system in more detail, with Figure 4 specifically showing an exploded view of the parts surrounding the latch mechanism which holds the deck in place at the roof of the trailer. Referring to ~igure 4 the deck 3 has a central longitudinal rib 7 to which is attached a bracket 9 which holds th~ latch. Bracket ~ has an elongated outer depending part 11 which is sized so that it can slide within an upper channel 13 which is secured to trailer body vertical rame member 15. Channel 13 has a lower channel 7~, which if damaged by a fork lift can be replaced without disassembly of the deck system, simply by first raising the deck up so that the trolley is fully within upper channel 13, thus freeing lower channel 78 which is then removed, replaced, and refastened.
Part 11 has a roller t7 rotatably mounted nt its lower end, and an upper and lower pair of rollers 91 to provide for easy movement and ~uiding of part 11 whilst it is moving within the upper channel 13 and lower channel 78.

- 4 -bracket 9 also includes a slidin~ bolt latch 19 wllich is spring biased with bolt 21 in its outward position and a rope 23 is secured ut the rear end of the bolt rocker handle through rocker handle 89 so that the bolt 21 can be withdrawn by pulling dowmward on the rope 23, when required to lower the dec~
from its roof stora~e position.
At the uppar end of rail 13, which is secured to the side of the trailer body, there is a retainer 25 above which the bolt 21 can slide to hold ~eck 3 in the raised stora~e position. To assist in movin~ the deck up and down, there i5 a spring counterbalance 26 for each side of the deck. If rope 23 is pulled and a counterbalance spring brakes, a secondary retainer 80 located lower than retainer 25 acts as a safety stop to "hold" the deck while it is still overhead. To hold the deck 3 do~n Qgainst the counterbalance spring upward force, after!the deck has been pulled down for loading, there is inverted retainer 82 located just above rail S to engage latch bolt 21.
Flush mounted adjustable load brackets 90, one at earh corners of the deck, are adjusted to hook over lip of rail 5, the hook preventing the deck disengaging from the inside of the rail 5 should the trailer flex and bow the walls outward. Bracket 90 can later be adjusted if the van body bows ~ith a~e. ~racket 9 also has a lip 81 to enga~e rail 5 at deck center.
Upper spring housin~ channel 83 has multiple holes for adjustment of spring 26 to accomodate trailer van posts of various ~idths. Sprin~ bracket 84 li~ewise is adjustable membe~s and so reduces the number of parts to stock.
The rail S as it is permanently fixed to the sides of the trailer will act as a protestor for the sides of the trailer when the movable decks are stored in the roof and are not being used. Furthermore, the rail 5, although it is shown as being one height throughout the trailer, can be arranged so th~t a portion of rail length may be moved with tools and refastened so that the deck-loadin~ hei~ht for part of the trailer length can be different in different parts of the trailer if so desired by the shipper.
In fi~ure S there is shown specificqlly, a preferred form of dec~
structure which is made from e~truded aluminum bo% members 27 which have e%truded aluminum support lips 87 to support I-beams 29 transversely between them, and transverse rods 31 passing along through the I-beams and through holes in the box members. 5pecial nuts 88 on ends of rod 31 sesure the structure to~ether as one unit. Conventional deck member fastenin~ is by

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welding, but welding is expensive, hard to repnir and causes welding stresses, whereas the method of using rods, cross I-beams, and nuts is quick and allows in-trailer repair with simple tools to remove and replaces threaded fasteners. The bo~ members 27 and torsional rigidity and offer resistnnce against fork lift collisions and the cross support of I-beams 29 lends itself to special-purpose larger decks just by cutting I-beams and rods lon~er as required to suit the special needs.
The upper surfaces 33 of the deck is formed from plywood which is fastened by self-tapping screws 35 to the box members of the deck structure and is preferably also glued in place onto the box members so creating a very strong rigid structure which is subject to very little flexure. This construction of the deck is very light so that it can easily be handled, with the counterbalance by one person and yet is strong enou~h to support large loads for instsnce, ~S00 to 4000 lbs. Even if over-loaded the box members 27 do not fracture immediately but bend first, allowing repair when convenient.
The deck utilized in figure 6 and the general structure is the same as that previously described except that at the ends of the two outer box member there is inserted a hooked projection 43 which can be utilized with the multi-height load rails of Adams patent 893,476 to support the deck at various adjustable heights.
No horizontal wall supporting rails S for the deck are therefore required with this embodiment as the decks can merely be held at the required height given by the positionlng load stops. However, to support the center of the deck, channel 92 is provided.
In the embodiment described, other features can be included if believed to be desirable, these features being for instance the use of a second retaining stop (secondary ramp 80) possibly & foot below the roof stop so that if the deck slips downwardly possibly due to a broken counterbalance spring, the deck will again be held at this lower position rather than proceeding quickly down so striking the operator.
The embodiments of the invention shown and described also do not have to be specifically adapted to various types of trailers in that standard parts of the inventive apparatus will fit many types of trailer structures, reguiring possibly only different positions of securin~ rivets etc.
As the apparatus is also constructed from a number of pre-assembled parts, _ ~ _ it is quite easy to maintain it in good working condition by replacing only damaged parts.
It is also possible to provide double or more sets of decks within a trailer, although of course it may t~ke additional space to arrange for storaKe of multiple sets of decking below the roof of the trailer.
~eferring to figure 7, shown is counterbalance spring system for a deck in which a pair of springs are retained within a tube (box member 27) which passes alon~ the length of the deck. Two positions of the d~ck are shown, the lower one A being a~ operating le~sl and showing extended sprin~s 45 which are retained resp~ctively at both ends of the deck by pins 47 and are connected at their other ends through wire ropes 49 to pins 51 at the upper corners of the trailer body. The upper position 8 of the deck is shown wherein both sprin~s 45 have retracted and partly counterbslanced the weighS of the deck when placing it up into its storage position.
It should be noted that figure 7 is only a diagr~mmatic view of an embodiment of this type of structure utilizing springs within the deck, and it is within the purview of the invention to include various other types of similar structure utilizing springs, wire ropes and pulleys to obtain suitable counterbalancing of the deck.
Figure 8 discloses another embodiment of alternate spring counterbalancing of the deck wherein torsion springs 53 are used at both ends of the deck, the torsion springs being secured to drums SS and the whole being mounted upon a shaft 57. Wire ropes S9 are wound upon the drums 55, the upper ends of the wire ropes being secured to pins in the top corners of a trailer body in the manner suggested in the pravious embodiment. The inner ends 61 of the torsion springs are rigidly secured to the central bo~ member of the deck and through adjusters, hence, after pre-loading of torsion springs 53, counterb~lancing of the deck can be achieved.
F;gure 9 relates to 8 somewhat different type of apparatus for holding a deck which consists of rails 63 which are hin~ed in the upper corners of a trailer body as shown in the circled part 65 which is enlarged for purposes of clarity. The hineing mechanism includes a torsion sprin~ 67 which is sufficient to hold the rail 63 in an upper storage position. ~a~h rail 63 has provision for load stop pins a-long its len~th and at least a stop pin and a hook 73 n3are its remote end. A rope 69 is secured near the remote end of 1401-~
~ - 7 -rsils 63 so that the rail can be pulled downwardly and pushed against the side of the trailer bndy, n hook 73 at the remote end of rails 63 hooking into a slot formed at a suitable position on the trailer body conveniently using a small bracket 86 for the attachment. In order for hook 73 to hook into the slot in bracket 86, rail 63 must hav0 elon~ated holes in the hinge so that rail 63 and hook 73 will raise slîghtly to engage bracket 86 once hook 73 is engaged on each side of trailer. The rails 63 cannot rotate back up due to torsion sprine force and cargo weight on deck 71 will be transferred to the trailer side via hook 73 through bracket 86. Bracket 86 could be a full length slotted rail similar in purpose to rail S.
Deck 71 is supported above the rails 63 against the roof of the trailer and is lowered when pulling the rails 63 downwardly. Deck 71 can then be retained in ;ts required lo&d position resting on stop pins at remote ends of rails 63 at each corner of the deck.
Note that the broken lines in figure 9 indicate the lowered position of dec~ 71. For palletized cargo, deck 71 may be a series of individual decking bars spaced throu~hout the length of trailer.
Figure 10 relates to an embodiment of decking bar which can be stored at roof level in the trailer, can be extended downwardly for use in the placing of decks thereupon, and is easy to handle. The diagrammatic representation of the self-storing deck supports si~ply illustrates a deck support 75 which is hung upon bars 77 so that the support 75 can swing like a pendulum. The lowered position for use is shown and also an upper storage position. To prevent swin~in~ during movement of the trailer, any type of suitable latchin~
mechanism can be utilized so that supports 75 can be effectively temporarily secured to the trailer container walls.
In ~se the supports 75 are lowered, and the operator utilizas his own decks; which could be multiple layer cardboard, which is often used as disposable decks some other liGhtwei~ht deck which may or may not be disposable, or palletized cargo may serve as the deck.
The pivoting of the bars 77 at the roof can also, if required, be away from the end of bars 77 and an over centre spring can be utilized above the upper pivot point to bias the supports upwardly during retraction and downwardly during use.
Telescopin~ rods may also be useful as bars 77 to achieve different 1401-l ' I;

working heights of supports 75.
The învention has now been described by reciting the aspects of its various embodiments, however it is understandable that many more embodiments of the invention can be utilized in the carrying out of this in~ention and the protection afforded is therefore limited only by the followin~ claims.

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Claims (6)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE PROPERTY OR
PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A container or trailer deck support system consisting of a plurality of units, each unit having a vertical channel on opposing side walls of the container, an elongated member slidable positioned within the channel, a bracket secured to the elongated member and a deck secured to the bracket so that the deck can be moved vertically within the container within confines dictated by the vertical channels, a torsion spring for counterbalancing the weight of the deck, and a support rail secured longitudinally along each of the longitudinal sides of the trailer body to support the decks when it is in its lowered position.

2. The system of claim 1, including a lock bolt at each side of the deck and a cooperative retainer on the trailer sides for holding the deck in an upper position against the roof of the container, and a rope at an end of the bolt for releasing the bolt so that the deck can be lowered.

3. The system of claim 1, wherein said deck consists of a box-shaped cross section member alone each longitudinal side, an intermediate longitudinal box-shaped cross section member, a number of transverse I-beam members between the longitudinal members, and an elongated tie rod extending transversely from one longitudinal side to the other alongside each transverse member.

4. The system of claim 1, wherein the support rails have an upwardly extending flange along their lengths and the deck has a downwardly extending lip extending along its longitudinal edges, the lips cooperating with respective flanges when the deck is in lowered position to hold the sides of the trailer body in contact with the longitudinal edges of the deck during flexure of the body.

5. The system of claim 2, including a safety retainer situated a short distance below the cooperative retainers for arresting falling of the deck should any of the torsion springs break during lowering of the deck.

6. The system of claim 2, including a lower retainer situated at the level of the support rail so that the deck can be held in its lowered position against the force of the torsion openings.