Freight container

Abstract

A liftable freight container (1) is provided with a support frame (F) mounted on hinges (H) on a support strut (S) to define a triangular structure, a stay (T) being pivotally mounted at the apex and having its distal end releasable connected (20) to the base (2) of the container. This strengthens the container for lifting at its corner fittings (8, 9). The stay can be folded back against the frame to allow the latter to be swung outwardly for loading/unloading.

Description

[0001] This invention relates to a freight container.

[0002] Intermodal freight transport in Europe (by road, rail and sea ferry) requires containers of maximum internal volume and minimum tare weight. Current European regulations allow a maximum container length of 13.6 m and a maximum width of 2.5 m/2.55 m. This width can accommodate two rows of 1.2 m standard pallets which, after allowing for practical clearances, allows 40 mm or so at most for each of two side wall structures.

[0003] Swapbody containers of 13.6 m currently exist. These containers have corrugated steel sides which are specially strengthened at locations 12.2 m (40 feet) apart along the sides (i.e. at the “40 feet” location) to provide, in effect, 12.2 m (40 feet) posts. At the top of each 12.2 m (40 feet) post is a standard I.S.O. fitting (corner casting) which allows the container to be top-lifted by a known 12.2 m (40 feet) spreader with twistlook connectors. Also, a standard laden 12.2 m (40 feet) container may be stacked on top of such a container.

[0004] However, such containers suffer from a drawback that freight cannot be loaded or unloaded except through a rear end door, whereas the great majority of road trailers (of this size) are curtain sided, which has the great advantage of allowing side loading and unloading.

[0005] The roof structure of 13.6 m curtainside swapbody containers now in common use is relatively flimsy. This is necessitated by the requirements for maximum side aperture height, which limits the structural depth allowable for the roof (commonly no more than 100 mm approximately). For the same reason, the structural depth of the base has to be kept to a minimum (currently approximately 250 mm) which results in a very flexible base structure which deflects very significantly when under load.

[0006] It is therefore impractical to stack a laden 12.2 m (40 feet) unit on top of a 13.6 m curtainside container, nor can a laden 13.6 m curtainside unit be stacked on top of another container since excessive base deflection would cause unacceptable loadings on the roof of the container underneath. Notionally, a rigid-walled 13.6 m unit could be stacked on a curtainside one, except that significant longitudinal racking forces would arise during transport and it is unlikely that the curtainside container could safely resist these longitudinal forces.

[0007] However, there is a strong demand for 13.6 m curtainside containers which also have the capability of being stacked laden and toplifted. Top lifting equipment is readily available at most docksides and intermodal depots; whereas, grapple lifting or sling lifting equipment is not readily available, being very specialised. Ship to shore container cranes invariably have top lifting equipment and a Lift On Lift Off (LO-LO) operation is highly desirable for deck cargoes on short-sea ferries. Also, many ferries carry containers stacked two-high below decks on Maffi-type platforms/cassettes. These Maffi cassettes commonly have a capacity of 70 tonnes and are rolled on and off is the ship (RO-RO) with special tractors, Currently, only a single curtainside container can be transported by this system, resulting in the waste of valuable ship space: In effect, an operator has to pay for two container slots, when moving only one container.

[0008] 13.6 m curtainside containers currently have I.S.O. fittings (or similar lightweight versions) in their base structure at the 12.2 m (“40 feet”) locations.

[0009] The purpose of these fittings is to allow twistlock connection of the container to a road chasses (trailer), a rail wagon or to a ship's deck. If a full I.S.O. fitting were provided in the roof structure at each 12.2 m (“40 feet”) location, and the top and bottom 12.2 m (“40 feet”) fittings connected by a structural “post” member, then the container would be top liftable and stackable. Unfortunately, such “posts” would prevent satisfactory side loading and unloading of the container.

[0010] One manner for overcoming the difficulty would be to make the “40 feet” posts removable. However this presents a further difficulty in that the post is necessarily heavy and impractical to be removed safely by manpower. Also, it would not be easy to make a satisfactory connection to the container at the top of the post, since the top is a long way from the ground and therefore, not easily accessible.

[0011] In our International patent application WO99/59899 there is disclosed an open-sided freight container with an angled stay detachably connected between the end wall and a base of the container, in order to limit flexing of the base. However because of its length, this stay is somewhat unwieldy.

[0012] In our co-pending patent application GB-A-2353277 (which is hereby incorporated by reference) a solution to the above problems is presented in the form of a hinged gate mounted on corner parts of the freight container.

[0013] However it would be desirable to provide a means of strengthening a container which, like the gate of GB 2353277 is hinged but which is easier to operate and more versatile.

[0014] According to the present invention there is provided a freight container including a base, a roof, fitting means located on the roof for lifting the container and/or stacking a further container on the roof, and support means moveable between a closed load-bearing position for transferring a load between the fitting means and the base and an open loading position in which the support means allows side access for loading and unloading of the freight container, wherein the support means comprises a frame hingedly mounted on the container so that it can swing open from one side of the container and a stay carded on the frame and moveable relative to the frame between a retracted position in which it allows side access to the container and an extended position in which its distal end is coupled to a structural member of the container.

[0015] Conveniently, the support means is hingedly fixed to a post of the freight container. The post can be, for example, a corner post or an end post.

[0016] Advantageously, the frame extends between two spaced-apart hinges. Said hinges preferably (but need not) define a substantially vertical hinge axis.

[0017] Conveniently, locking means are provided for locking the support means in the closed load-bearing position.

[0018] Preferably the distal end of th stay has an elongate aperture arranged to receive a pin of the locking means with sufficient play to allow limited flexing of the container.

[0019] Conveniently, two fitting means are mounted on the roof proximate a junction of the roof with a side wall of the container, the two fittings being separated by a predetermined distance less than a length of the side wall, resulting in a top-liftable container. Preferably, the predetermined distance is 12.2 m (40 feet). Preferably the container is stackable when laden.

[0020] In general, the achievement of top lift and laden stacking capabilities does involve significant additional tare weight compared with similar containers which do not have these capabilities. The complete structure, in particular the base structure, has to be heavier in order to comply with the international Container Safety Convention (CSC) which is applicable to all top-liftable containers. In order to obtain CSC Certification the unit has to be tested to 2.0R (where R equals the maximum gross rated mass) whereas grapple and sting lifted containers do not require CSC Certification, but merely have to comply with CEN standards for swapbodies which call for testing to 1.5R only.

[0021] In a preferred embodiment of the present invention the stay extends diagonally relative to the side of the container when in its extended position.

[0022] This feature strengthens the container and minimises the increase in weight needed to meet CSC certification.

[0023] Preferred embodiments of the invention will now be described by way of example with reference to the accompanying drawings, in which:

[0024] FIG. 1 shows a side view of a freight container according to the invention with the frame and stay in a load-bearing position;

[0025] FIG. 2 shows a partial view of the freight container of FIG. 1 mounted on a lorry with the frame and stay in a freight loading/unloading position;

[0026] FIG. 3 is a plan view of part of the container shown In FIG. 2;

[0027] FIG. 4 is a partial side elevation showing the frame and stay of FIGS. 1 to 3 in more detail; and

[0028] FIG. 5 is a similar partial side elevation showing a further embodiment.

[0029] In the Figures, like reference numerals denote like parts, parts in FIG. 5 which are similar to parts in FIG. 4 being denoted by primed reference numerals.

[0030] As shown in FIGS. 1 to 3, a freight container 1 of the invention has a base 2 and corner posts 3, 4 supporting a roof 5, the roof being additionally supported by three equally spaced intermediate posts 6 which are movable in a known manner. The sides of the container are closed by a curtain 7 covering the intermediate posts 6 such that the curtain 7 may be drawn aside for loading and unloading the container 1 as best seen in FIGS. 2 and 3. The container is provided adjacent to its sides on its base and roof with known I.S.O. corner fittings 8, 9, 10, 11 which are separated by a distance of 12.2 m (40 feet) along the side of the container such that the roof corner fittings 8, 9 are vertically above the base corner fittings 10, 11 respectively.

[0031] There is further provided at each end of the container a frame F mounted on a vertical support post S by upper and lower hinges H to form a triangular assembly, a stay T being pivotally mounted at the apex.

[0032] In the closed or load-bearing position shown, stay T is aligned with the upper limb of frame F and its distal end is releasably secured at coupling 20 to the base 2 of the container In this configuration, when the container is lifted from corner fittings 8 and 9, stay T and its co-aligned upper limb of frame F are tensioned and carry more of the load than supports S.

[0033] As best shown in FIG. 3, the frame structure F is so hinged that it can rotate through 135° about a vertical axis from the closed load-bearing position to an open loading/unloading position (as indicated by the arrow A) so that access for side loading and unloading of the container 1 is provided. As shown in FIG. 3, stay T can be swung about horizontal pivot axis a to lie against e.g. the lower limb of frame F.

[0034] As also shown in FIG. 3, the roof 5 is strengthened by a substantial transverse roof beam 12 which is needed to resist eccentricity moments arising at the I.S.O. top lift fittings. This eccentricity occurs because the 12.2 m (“40 feet”) post is (of necessity) located close to the 2.5 m outer “envelope” (so as to allow Internal width for two 1.2 m pallets side by side).

[0035] To load or unload the container 1, the curtain 7 is drawn aside and the intermediate moveable posts 6 removed in a known manner and the frame structure F, T is moved from the load-bearing position to the open loading/unloading position. When the loading or unloading is completed, the frame structure is moved to the load-bearing position and locked in position at coupling 20. The moveable posts 6 are replaced and the curtain 7 closed.

[0036] Referring to FIG. 4, the frame F is shown in more detail and comprises an upper limb f1 and a lower limb 12 which extend diagonally inwardly from vertically spaced apart hinges H to a pivot P at an apex of a symmetrical triangular structure defined by the frame and vertical support post S.

[0037] In the closed load-bearing position shown, the distal (lower) end of stay T is secured by a coupling 20 to the base 2 of the container and transmits the load on base 2 to the upper hinge H and hence to I.S.O. corner fitting 9. The coupling 20 can be released by means of a handle 21 which operates a conventional locking mechanism (not shown) and thus swing about pivot P in a vertical plane as indicated in phantom until it lies against lower limb f2.

[0038] Preferably the locking mechanism comprises a pin which can be secured in an elongate aperture 25 in stay T. This allows limited flexing of the base 2.

[0039] The frame assembly can then be opened outwardly on hinges H, using handle 22.

[0040] The locking mechanism may, for example, be as shown in FIGS. 3, 4 and 5 of WO99/59899.

[0041] FIG. 5 shows a variant in which stay T′ extends diagonally upwardly to a coupling 201 in the roof 5. As shown in phantom stay T can b swung against upper limb f1′.

[0042] In a further variant the hinges H could be mounted on an upright post in a mid-portion of the container and stay T could extend diagonally downwardly from the frame towards an end wall of the container.

Claims

1. A freight container including a base, a roof, fitting means located on the roof for lifting the container and/or stacking a further container on the roof, and support means moveable between a closed load-bearing position for transferring a load between the fitting means and the base and an open loading position in which the support means allows side access for loading and unloading the container, wherein the support means comprises a frame hingedly mounted on the container so that it can swing open from one side of the container and a stay carried on the frame and moveable relative to the frame between a retracted portion in which it allows side access to the container and an extended position in which its distal end is coupled to a structural member of the container.

2. A freight container according to claim 1 wherein the support means is hingedly fixed to a post of the freight container.

3. A freight container according to claim 1 wherein the frame extends between two spaced-apart hinges.

4. A freight container according to claim 3 wherein the hinges define a substantially vertical hinge axis.

5. A freight container according to claim 1 wherein locking means are provided for locking the support means in the closed load-bearing position.

6. A freight container according to claim 1 wherein, in the closed load-bearing position, the stay extends diagonally from a pivot on the frame to a releasable connection to said structural member.

7. A freight container according to claim 5 wherein the distal end of the stay has an elongate aperture arranged to receive a pin of the locking means with sufficient play to allow limited flexing of the container.

8. Cancel.

9. A freight container according to claim 2 wherein the frame extends between two spaced-apart hinges.

10. A freight container according to claim 9 wherein the hinges define a substantially vertical hinge axis.

11. A freight container according to claim 2 wherein locking means are provided for locking the support means in the closed load-bearing position.

12. A freight container according to claim 3 wherein locking means are provided for locking the support means in the closed load-bearing position.

13. A freight container according to any preceding claim 4 wherein locking means are provided for locking the support means in the closed load-bearing position.

14. A freight container according to any preceding claim 9 wherein locking means are provided for locking the support means in the closed load-bearing position.

15. A freight container according to any preceding claim 10 wherein locking means are provided for locking the support means in the closed load-bearing position.

16. A freight container according to claim 2 wherein, in the closed load-bearing position, the stay extends diagonally from a pivot on the frame to a releasable connection to said structural member.

17. A freight container according to claim 3 wherein, in the closed load-bearing position, the stay extends diagonally from a pivot on the frame to a releasable connection to said structural member.

18. A freight container according to claim 10 wherein, in the closed load-bearing position, the stay extends diagonally from a pivot on the frame to a releasable connection to said structural member.

19. A freight container according to claim 15 wherein, in the closed load-bearing position, the stay extends diagonally from a pivot on the frame to a releasable connection to said structural member.

20. A freight container according to claim 7 wherein the distal end of the stay has an elongate aperture arranged to receive a pin of the locking means with sufficient play to allow limited flexing of the container.

21. A freight container according to claim 19 wherein the distal end of the stay has an elongate aperture arranged to receive a pin of the locking means with sufficient play to allow limited flexing of the container.