AU621068B2 - Locking system for a collapsible container - Google Patents

Description

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AUSTRALIA

Patents Act ^68 COMPLETE SPECON

(ORIGINAL)

Class Int. Class Application Number: Lodged: o 0o oo 0 0 ft o00 o o o o o offl 0 f 0 0 0 0 o o o o 0 00 o a o S0o o °o 0 0 0 0 00 0 0 o o, o 0 0 0 6 o a e a 000 0 0 0 tt 0000 011 0 t 6tt|

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Complete SrFcification Lodged: Accepted: Published: Priority Related Art: Name(s) of Applicant(s): Address(es) of Applicant(s): APPLICANT'S REF.: "LOCKING SYSTEM FOR A COLLAPSIBLE

CONTAINER"

MARTIN CLIVE-SMITH 66 Leam Terrace, Leamington Spa CV31 1BQ, United Kingdom Actual Inventor(s): Martin Clive-Smith Address for Service is: PHILLIPS, ORMONDE AND FITZPATRICK Patent and Trade Mark Attorneys 367 Collins Street Melbourne, Australia, 3000 Complete Specification for the invention entitled: "LOCKING SYSTEM FOR A COLLAPSIBLE CONTAINER" The following statement is a full description of this invention, including the best method of performing it known to applicant(s): P19/3/84

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Title: LOCKING SYSTEM FOR A COLLAPSIBLE CONTAINER In the field of the shipping containers there is a type of special container called a flatrack comprising a horizontal platform base with vertical posts usually one at each corner.

The posts sometimes have a wall connected between them. One type of flatrack is collapsible wherein the corner posts are attached to the base by massive pivot pins. They can either be locked in the vertical position or the corner posts can be unlocked and folded down to the base. Once folded other folded containers can be stacked upon it to enable economical storage and transport.

When the posts are erect, substantial handling forces can be applied to the top of the posts in any direction during sea and land transport. The geometry of the posts must remain firm to ensure that other similar containers can be stacked and supported on top of the posts. Thus it is important that not only are the posts held rigidly in place but they must resist the operating force. And this puts enormous forces onto the locking device.

The conventional solution to the problem of post movement and strength of attachment to the base is for tight fitting releasable locking devices and close fitting hinges and abutments. In practice there has to be a working clearance between post and hinge pin and hinge pin and base; post and locking device and locking device and base. The pin and locking devices have to be located close together so as not to encroach the cargo space so that a small clearance here causes a significantly larger wobble at the top of the post. Because handling forces can act in any direction on the top of the post, the tight fitting of the locking device and abutments is difficult and expensive to achieve. It would thus be an advantage if the post could be engaged with the base without pins or locking devices.

According to the present invention there is provided a \platform based cargo container including: a base structure; KW 2 post members mounted on the base structure for pivotal movement between a folded position lying parallel and adjacent to the base structure and an erected position upstanding from the base structure; and, locking mechanisms for selectively locking each post member in the erected position, each locking mechanism having abutment parts on the respective post member and base structure, the abutment parts interengaging when the respective post member is in the erected position to prevent pivotal movement thereof toward the folded position, each locking mechanism also having displacement means for retaining the abutment parts in interengagement when the respective post member is in the erected position and being operable to displace the respective post member while in the erected position in a direction parallel to the plane of the base structure so as to disengage the abutment parts and thereby permit pivotal movement of the post member.

A preferred embodiment of the invention will now be described with reference to the following drawings in which:vRA41 -03 Iw t

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Figure 1 shows a perspective view of a collapsible flatrack container.

Figure 2 shows a side elevation of a stack of folded collapsible flatracks.

Figure 3 there can be seen a detailed perspective view of the lower corner arrangement with the post erect.

Figure 4 shows the same as Figure 3 with the post folded to the base.

Figure 5 there can be seen a detailed side elevation of the lower corner arrangement with the post erect and partly cut away to show the inner workings, Figure 6 shows the same as figure 5 but with the post disengaged from the base.

Figure 7 shows the same as figure 6 but with the post partly folded down towards the base.

Figure 8 shows the same as figure 7 but with the post folded down onto the base.

In figure 1 there is seen a collapsible flatracK conprising-asteel base 1 with timber floor 2, end rails 3 and side rails 4, and a wall 8 at each end with posts 6, top rail 7 and bottom rail 12. At each corner of the flatrack is a corner fitting 9, 10 comprising a Known hollow rectangular steel box which has in it apertures 5 formed in its sides to accept Known hooks and twistlocks. The posts 6 are Sengaged with the base i in the erect position. When the posts 6 are disengaged from the base i they can fold down onto the base I about arrows Typically the materials of construction of the flatracK are a high strength welded steel with a floor of timber.

In figure 2 a number of similar flatracks 14,15,16,17,18 can be seen collapsed and stacked one upon another.

In figure 3 the post 6 is erect. There is as part of the post 6 a back plate 13 with an aperture 19 through which projects a nose -3- II

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I In figure 4 the nose can be seen to be part of a block 21 which is welded to corner fitting 10 so as to form part of the rigid assembly of base 1. Also fixed to the block 21 are an upper block 22 and lower block 23. The plate 13 has on either side as part of the rigid assembly of the post 6 two hinge plates 24,25 with holes 28 through which passes a pin 26. When the post 6 is folded as shown, the plate 13 is horizontal so that Known handling devices such as twistlocks and :ooks can enter aperture 19 and either lift the flatrack 14 or be used to link other flatracks such as 15, 16.

Ii figure 5 hinge plate 24 has been cut away to reveal the inner workings of the corer 11. The profile of the hinge plate 24 is shown by dotted line 24'. Through block 21 is formed a slot 27 and by looking through the slot 27 one can see the hinge plate 25 which has a hole 28 formed in it through which the pin 26 passes. Although the hinge plate 24 has been removed there has been left behind a wedge shaped tongue 29 which is'welded rigidly to the inside face of plate 24. The tongue 29 is in contact with upper block 22 and lower block 23, Lower block 23 is positioned at an angle to match the tapered face of the tongue 29. The tongue 29 cannot in this position move neither up nor down and by virtue of its connection to the hinge plate 24 and post 6 prevents vertical movement of the post 6.

o Furthermore should the post 6 be drawn towards the base 1 horizontally, the tongue 29 would become more tightly engaged with 4 4a the blocks 22, 23.

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The nose 20 can be seen to be in contact with the bridge 30 of the aperure 19. The back plate 13 can also be seen resting on the corner fitting 10 so that the plate 13 cannot move substantially upwards nor down thus restraining post 6. Thus any vertical forces acting on the post 6 are supported by the base 1.

6 4 Should a horizontally acting force dennoted by arrow B in figure 1 act on the corner fitting 9, a moment of force is caused about the tol corner 11. The moment is resisted by bridge 30 acting on nose 20 and tongue 29 acting on lower block 23. Since the nose 20 and block 23 form part of the base 1, the moment is resisted without the wall 8 folding over towards the base 1. Any resulting horizontal movement tIt I at the hinge plates 24,25 is resisted by the tongue 29 and blocks 22,23.

-4i If the force denoted by arrow B is reversed so as to exert outwards on the post 6, the resulting moment about the corner 11 is rcs-'ted by the lower part of plate 13 acting on the corer fitting 10 and the tongue 29 acting on the upper block 22. However any horizontal movement of the hinge plates 24,25 would tend to draw the tongue 29 out of engagement with the blocks 22,23. The reversed force B acting high up on the post 6 causes very much higher reaction forces between tongue 29 and upper block 22 and between' bridge 30 and corner fitting because the length of the post 6 is typically 10 times longer than the distance between the points of reaction at tongue 29 and bridge Since frictional resistance to horizontal movement at tongue 29 and bridge 30 resulting from force at arrow B is proportional to the higher reaction forces at tongue 29 and bridge 30, typically, the friction will prevent the tongue 29 and bridge 30 from disengaging with block 22 and corner fitting 10 respectively. To assist with the resistance to disengagement, in figure 5 the upper block 22 might have an inclined surface 22' matched by an inclined surface 29' of tongue 29, Any reaction between the incline surfaces 22', 29' would thus have a horizontal component opposing a reverse force from arrow B and thus resisting disengagement.

Should friction fail to prevent disengagement, in figure 5 a link 31 attached to the pin 26 has been provided. The link 31 has a hole in Sit through which the pin 26 passes so that the pin 26 joins link 31 to hinge plates 24,25. At the other end of link 31 is a hole32 to which is attached a,over-centre toggle device 33 which holds the link 31 and thus post 6 against horizontal movement.

The over-centre toggle 33 is of a Known configuration comprising a handle 34 which is attached pivotally by a pin 35 to the side rail 4.

SThe link 31 is attached by a pin 36 to the handle 34. Rotation of the handle 34 is prevented in one direction by a stop 39 attached to the S side rail 4. Any pull on the link 31 by virtue of the alignment of the pins 35,36 causes to handle 34 to rest more firmly on the stop 39 thereby preventing unlocking of the post 6.

In figure 6, the handle 34 has been rotated about its pivot pin St c and this movement translated through link 31 to pin 26 and thus pushing the tongue 29 and bridge 30 out of connection with the blocks 22,23 and nose 20 respectively. The pin 26 can be seen to have moved along slot 27. The plates 25,25 rest on the corner fitting 10 and i i, 4 the pin 26 remains in the slot 27 so that the post 6 cannot fall outwards away from the base i. However the tongue 29 is now clear of the lower block 23 and the bridge 30 is clear of the nose 20. The pin 26 now becomes a pivot for the post 6 so that the post 6 can pivot about pin 26 towards the base 1 as seen in figure 7.

In figure 8 the wall 8 post 6 can be seen folded down to a horizontal position. A support 38 which is welded to the hinge plate 24 can be seen in abutment with the corner fitting Any downwards force acting on the plate 13 can be supported by the support 38 thereby relieving the load on pin 26. Alternatively plate 40 which is welded to plate 13 can be devised to abut the top of block 21 to take the downwards forces. Lifting forces acting on the plate 13 act through the plates 24,25 through pin 26 and then to the base 1.

It is envisaged that other known devices might be used in place of the over-centre toggle 33 to restrain and cause the horizontal movement either as integral parts of the container or loose items. The blocks 22, 23 might be welded to block 21 for ease of assembly or be case from steel as one piece.

It is a matter of choice whether the pin 26 be of small dimension and play no significant part in supporting the erect post 6, or be increased to such a size capable of reacting in conjunction with the tongue 29 and or bridge 30 to support the post 6.

It is envisaged that in another arrangement the over-centre toggle might be replaced with a cam assembly (not shown) mounted directly between the plates 24,25 and block 21. The cam assembly could include a cam member mounted for rotation with a handle. The cam member could be connected to or engage with the pin 26 or part of the post 6, so that upon rotation of the cam member the post 6 is displaced relative to the base i. If the cam assembly was of sufficient size, it is envisaged that it might act with bridge 30 or tongue 29 to support the post 6 against handling forces.

WKW 6- 0i QV~ The tongue 29 could be made as a parallel sided tongue with no taper. The surface of bridge 30 and the mating surface of nose 20 might be tapered so as to provide a wedging engagement as the bridge 30 enters the space between nose 20 and corner fitting If the pin 26 is removed, the posts 6 and wall 8 can be removed from the base 1. Since the block 21 is substantially below the level of i 6A flIoor 2, the base i can be used as a s implIe cargo carry ing plIatf orm.

The corner fitting 10 might be replaced by any structural comnponent formed as part of the base sufficient to support the-plate '13. The nose 20 mright be enlarged to substantially fill the aperture 19 such that the nose 20 would support both upward and downward movemrent, of the plate 13 obviating the need -for support by corner fitting 0 47

Claims (9)

1. A platform based cargo container including: a base structure; post members mounted on the base structure for pivotal movement between a folded position lying parallel and adjacent to the base structure and an erected position upstanding from the base structure; and, locking mechanisms for selectively locking each post member in the erected position, each locking mechanism having abutment parts on the respective post member and base structure, the abutment parts interengaging when the respective post member is in the erected position to prevent pivotal movement thereof toward the folded position, each locking mechanism also having displacement means for retaining the abutment parts in interengagement when the respective post member is in the erected position and being operable to displace the respective post member while in the erected position in a direction parallel to the plane of the base structure so as to disengage the abutment parts and thereby permit pivotal movement of the post member.

2. A container as claimed in claim 1, wherein each locking mechanism includes an abutment body fixed on the base structure and having a nose portion providing one of the abutment parts, and an abutment plate fixed to the respective post member and having an aperture therein, an edge region of the abutment plate providing another of the abutment parts, the nose portion being receivable in the aperture for engagement between the abutment parts.

3. A container as claimed in claim 1 or 2, wherein each locking mechanism includes at least one abutment block fixed relative to the base structure and providing at least one of the abutment parts, and an abutment tongue fixed to the respective post member and providing another of the abutment parts.

4. A container as claimed in claim 3, wherein the or one of the abutment blocks and the abutment tongue have opposing abutment surfaces inclined at an angle to the direction of displacement of the respective post member so that, upon displacement of the post member to interengage the abutment 6 block and tongue, the abutment surfaces engage one another in lei8 )yw -8a- a wedging action.

A container as claimed in any preceding claim, wherein each locking mechanism further includes a mounting pin connected to the post member and received within a mounting slot fixed relative to the base structure, the mounting pin being movable along the slot to displace the post member when in the erected position.

6. A container as claimed in any preceding claim, wherein each displacement means includes a cam assembly connected directly or indirectly between the base structure and respective post member and operable to displace the post member.

7. A container as claimed in any one of claims 1 to wherein each displacement means includes an over-center toggle assembly connected directly or indirectly between the base structure and respective post member and operable to displace the post member.

8. A container as claimed in claim 5, wherein each mounting pin is located at a base of the post member adjacent the base structure, and the mounting pin is rotatably received within the mounting slot so as to mount the post member for pivotal movement between the folded and erected positions.

9. A container as claimed in claim 2 or any claim appended thereto, wherein the abutment plates are arranged on the post members so that, when the post members are in the folded position, another container can be positioned on top of the container and supported on the abutment plates. A platform based cargo container, substantially as hereinbefore described with reference to what is shown in the accompanying drawings. DATED: 17 July, 1991 PHILLIPS ORMONDE FITZPATRICK Attorneys for: MARTIN CLIVE-SMITH 3369E S-9- j r