FIELD OF THE INVENTION The present invention relates to a bulk container discharge device which has been developed for discharging the contents of shipping containers into cargo ships.

The invention has been developed principally for discharging the content of shipping containers of the kind that are transported by road or rail and which contain a flowable material which can be discharged into large capacity cargo ships. The invention has also been developed in relation to flowable material of the kind which is mined, such as coal or iron oxide.

However, it should be appreciated that the invention is not limited to the above applications, but could have applications for transfer of shipping containers between different modes of transport, such as from road or rail transport to a shipping container (as opposed to a cargo ship), and for transfer of the contents of shipping containers to vessels other than cargo ships, such as holding bays which might be found at a port.

BACKGROUND OF THE INVENTION

A reference herein to a patent document or other matter which is given as prior art is not to be taken as an admission that that document or matter was known or that the information it contains was part of the common general knowledge as at the priority date of any of the claims.

Mining material for transport is normally shipped by road or rail to a port at which the material is loaded into a cargo ship for transport to a different part of the country, or to a different country. The mined material is normally transported in shipping containers of a standard size and dimension and the transport is usually by semi-trailer, road train or by rail. It is possible that transport could be by a sea-going vessel although that is rare, at least in Australia. With flowable mined material, such as iron oxide, the shipping containers normally are discharged at the port to form a large body of ore which is then conveyed on a moving conveyor from the port into the hold of a cargo ship. It will be appreciated that the conveyor can be of significant length , but a disadvantage with this approach is that both the body of ore and the ore as it is conveyed to the hold, is open to atmosphere, so that fine particles of the ore can be blown by wind into the surrounding areas as dust. This has been found to present problems where the particles have been blown into the surrounding waterways, as the waterways have become polluted, affecting marine life and some times resulting in unpleasant odour and also affecting the appearance of the waterways. Iron oxide in particular can affect the colour of water into which is it discharged, while it can also have a significant polluting effect, affecting marine life in the immediate area.

An additional drawback with the use of a conveyor is the cost and the inflexibility of its use. As to cost, the construction of a conveyor can be in the order of AU$3,000,000 or more. In relation to flexibility of use, once a conveyor is erected, it is fixed in place, so that adjustment of the point of delivery is not possible for example.

Applicant has recognised a need for an alternative manner of loading material between road and rail transport into the holds of cargo ships, that can eliminate or at least alleviate the release of ore dust into the environment and/or which provides cost or operational advantages.

SUMMARY OF THE INVENTION

In a broad aspect of the invention, there is provided a bulk container discharge device, the device being operable to lift a container for positioning the container at a position for discharge of the contents of the container into the cargo hold of a cargo ship, the device further being operable to rotate the container for discharging the contents of the container from the container.

In a more specific form of the invention, there is provided a bulk container discharge device, including a frame for connecting to a container, the frame including first and second frame parts, the first and second frame parts being connected together and the second frame parts being rotatable relative to the first frame parts, the first frame part being connectable to a lifting device and the second frame part being connectable to a container, the discharge device being operable such that with a container connected to the second frame part and with a lifting device connected to the first frame part, the container can be lifted with the discharge device by the lifting device into a discharge position for discharge of the contents of the container, and in the discharge position, the second frame part can be rotated relative to the first frame part to discharge the contents of the container. The present invention also provides a method of loading a cargo ship, including lifting a container and positioning the container at a position for discharge of the contents of the container into the cargo hold of a cargo ship and rotating the container for discharging the contents of the container from the container. The present invention also provides a method of loading a cargo ship, the method including connecting a container which contains material to be discharged into the hold of the cargo ship to a bulk container discharge device which includes first and second frame parts, the first and second frame parts being connected together and the second frame part being rotatable relative to the first frame part, the method further including connecting the container to the second frame part, connecting a lifting device to the first frame part, lifting the discharge device and the container with the lifting device to position the container at a discharge position for discharge of the contents of the container into the cargo hold, rotating the second frame part relative to the first frame part to discharge the contents of the container into the cargo hold.

A major advantage with the discharge device of the present invention is in relation to cost and flexibility of use. In relation to cost, the device of the invention is expected to realise savings in the order of over 70% compared to the cost of a conveyor. In addition, the use of the discharge device of the present invention provides great flexibility, because it is not fixed in place and can be used anywhere within approximately 1 0 to 15m from the vehicle from which the container is unloaded. Still further, there is expected to be no time disadvantage in the use of the discharge device of the present invention as compared to the conveyor system presently in use. In fact, with proper usage, the discharge device of the present invention could facilitate loading of a cargo ship faster than is capable now with the conveyor system.

While the financial and operational benefits mentioned above are advantageous, a major benefit provided by the discharge device of the present invention is environmental, in that the ore which is loaded by the discharge device of the present invention can be maintained against exposure to the atmosphere until it is discharged into the hold of the cargo ship. Thus, the containers in which the ore is transported to the port can be closed and can remain closed while the container is lifted by the discharge device to the position for discharge of the contents of the container into the cargo hold. In this manner, the first time the contents of the container are exposed to atmosphere is adjacent to or within the cargo hold. Thus, the potential for wind blown particles to escape into the surrounding area is significantly reduced, or even eliminated.

In a bulk container discharge device according to the invention, the first frame part can include a pair of end assemblies which are spaced apart and a span assembly which connects between them. The span assembly can be generally rectangular in plane view, and can be braced as required to provide sufficient strength and stiffness for lifting a container. The end assemblies can extend generally perpendicular to the plane of the span assembly and generally extend downwardly from the span assembly.

The end assemblies can be of any suitable shape such as square or rectangular, although in some forms, sides of the end assemblies converge from a position spaced apart at the span assembly, to a closer position remote from the span assembly. Thus, the end assemblies can have a somewhat triangular shape.

The second frame part can include a first rotational frame part, which is rotatably connected to one of the end assemblies. In some forms of the invention, each of the end assemblies can have a rotational frame part rotatable connected thereto.

The rotational frame parts rotate relative to the end assemblies and can be driven to rotate by a rotation assembly. The rotation assembly can be of any suitable kind, although in one form, that assembly includes a wheel which is fixed to a shaft and which is driven to rotate. Drive of the wheel causes drive of the shaft and in this form of the invention, the or each rotational frame part can be fixed to the shaft so that rotation of the wheel causes rotation of the rotational frame part or parts.

Any suitable drive arrangement can be used to drive the wheel described above, and in one form of the invention, the drive wheel is a toothed wheel which is driven by a chain, the opposite ends of which are connected to respective hydraulic cylinders. The drive therefore is initiated by the ram of one of the cylinders extending, with the ram of the other cylinder retracting. The arrangement can be such as to provide a precise 180 ° rotational movement of the wheel, which thus drives the shaft and the rotational frame part also through 180°. Accordingly, with the container connected to the rotational frame part, the container can be drive through 180°. The discharge device of the invention can be arranged so that when a container is connected to it, the container tends to rest in an upright condition. Thus, the connection between the discharge device and the container is preferably offset from a neutral axis of the container, so that the container tends to rotate in a direction which is opposite the direction the container is rotated to discharge its contents.

The discharge device of the invention can include a closure or lid removal device for removing the closure or lid of a container which is being used with the discharge device. In some forms of the invention, the removal device can be a retractable device, which has an extended and retracted condition. The removal device can be operated so that when the container is about to be rotated for discharge of its contents, the removal device can extend, grip the lid or closure and then retract to remove the lid or closure from the container.

The removal device can include latches in order to grip the lid or closure and the latches can be shiftable from a release condition to a grip condition. That movement can be hydraulically or pneumatically controlled. The removal device can act in a scissor motion, so that in the retracted condition, it is collapsed, and in the extended condition, it is expanded. Hydraulic or pneumatic cylinders can be employed to shift the removal device in that manner. The present invention can employ any suitable arrangement to connect a container to the discharge device, however in one unique form, a simple rotational connection is made, whereby one or more spigots are received through an opening in the container and the spigots are rotated to bring a supporting surface underneath a surface of the container, so that upon lifting of the device relative to the container, the supporting surface bears against the container surface and lifts the container.

In the above embodiment, the device can include four spigot arrangements and an automatic rotation system can be employed to rotate the spigots once they have been received in the openings in the container. In one form, a bar can connect to the spigots eccentrically, so that movement of the bar rotates the spigots and the arrangement can be such that movement of the bar in a first direction rotates two spigots associated with one of the rotational frame parts, although if two rotational frame parts are employed, the same system can be used on each of those parts. The bar can be driven in a first direction by one cylinder and in a second direction by second cylinder, or although a single cylinder can be used to drive the bar in each direction.

To ensure that the spigot remains in the connected condition in which a container can be lifted, or in the release condition in which a container can be released from the discharge device, an over centre spring arrangement can be employed. In that arrangement, the spring will apply a biasing influence to maintain the spigots in whichever of the connected or release conditions the spigots have been rotated to by the drive arrangement which is employed. It is a feature of the invention that the discharge device is expected to be a very light weight device, so that the weight of the containers used with the device can be maximised. Initial testing indicates that a total weight of the discharge device will be in the region of 6,000 kg. The containers to be used with the discharge device are expected to weigh approximately 3,200 kg. A normal crane lifting capacity is in the order of about 50,000kg. Thus, the available weight of material to be discharged into the cargo hold will be in the region of 40,800 kg.

Some prior art machinery which involves cranes to lift containers utilises extremely heavy motors and gear boxes so that a mass of approximately 13,000 kg plus the weight of the container is a starting point, before the container is filled with mining material. Thus, in those prior art arrangements, the weight available for the mined material is approximately 25,000 kg as compared to the present invention which is expected to be in the region of 33,800 kg.

BRIEF DESCRIPTION OF THE DRAWINGS

In order that the invention may be more fully understood, some embodiments will now be described with reference to the figures in which:

Figure 1 illustrates a bulk container discharge device according to one embodiment of the present invention.

Figures 2 to 4, illustrate the discharge device of Figure 1 in 3 stages of operation during the discharge of contents from a container.

Figures 5 to 8 illustrate the part of the discharge device of Figure 1 that is used to lift the lid from a container. Figures 9 and 1 0 illustrate the portion of the discharge device of Figure 1 that is used to fix a container to the discharge device.

Figures 1 1 and 12 show a look arrangement for locking the frame parts of Figure 2 against movement.

DETAILED DESCRI PTION OF THE DRAWINGS

Figure 1 illustrates a bulk container discharge device 1 0 according to one embodiment of the present invention. The discharge device 10 includes a frame 1 1 which comprises first and second frames parts 1 2 and 13. The frame parts 12 and 1 3 are rotatable relative to one another through a rotation arrangement which comprises a pair of hydraulic cylinders 14, which drive a gear wheel 15. The arrangement of cylinders and gear wheel is repeated at each end of the device 10, although the full rotation arrangement is visible only at one end in Figure 1 .

The cylinders 14 operate to rotate the gear wheel 15 through a chain (not shown) which is fixed to ends of the rams 1 6 of the cylinders 14 and which engages the peripheral teeth 18 of the gear wheel 15. In Figure 1 , only one of the rams 1 6 is shown extended from its respective cylinder 14, as the ram of the other cylinder 14 is fully retracted into its associated cylinder and only the very end 17 of the ram 16 is visible.

The chain which is not shown in Figure 1 is, in practice, connected to the respective ends 17 of the rams 1 6 of the cylinders 14. The chain extends about the gear wheel 15 to engage the peripheral teeth 18 of that wheel and as one ram 16 extends from its associated cylinder 14, the other ram 16 of the other cylinder 14 is retracted. The hydraulic drive which is used to extend and retract the rams 16 of the cylinders 14 is a closed loop system such that hydraulic fluid which is used to extend the ram 16 of one of the cylinders 14 is taken from the other of the cylinders 14, such that the ram 1 6 of that cylinder retracts. By this mechanism, as one ram 1 6 moves in any direction, the ram of the other cylinder moves in the opposite direction an equal amount.

The frame parts 1 3 are fixed to the same shaft as the gear wheels 15 such as through a keying or splined arrangement, so that as the gear wheel 15 is rotated, each of the frame parts 1 3 also rotate in the same direction. This is illustrated in Figures 2 to 4, in which Figure 2 shows the discharge device 10 in the position illustrated in Figure 1 , but with a container 20 mounted to the frame parts 13, while Figures 3 and 4 show the container 20 rotated through 45° and 180° respectively. By the operation shown in Figures 2 to 4, the contents of the container 20 can be discharged into the hold of a cargo ship when the container 20 is in the upended position shown in Figure 4.

Returning to Figure 1 , the frame part 12 of the discharge device 10 includes end assemblies 25 at each end of the part 12 and the end assemblies 25 include a pair of upright members 26, a base member 27 and a bridging structure 28. The bridging structure 28 includes a plurality of members that bridge between the upright members 26.

A support plate 29 supports a bearing through which the shaft 30 to which the gear wheel 15 is fixed extends, and the shaft 30 extends through to connection with the frame part 13.

The frame part 12 further includes a span assembly 35, which includes span members 36 that extend between the pair of end assemblies 25 and a plurality of bracing members 37, which extend between the span members 36. The end assemblies 25 and the span assembly 35 forms a rigid frame part 12.

The ends of the cylinders 14 are fixed to plates 38 at the top of each of the upright members 26. The connection between the cylinders 14 and the plates 38 is a pin connection, so that the cylinders 14 have some freedom to move as they operate to rotate the gear wheel 1 5.

In the operation of the discharge device, a container 20 is connected to the frame parts 1 3 in a manner that will be described later herein, and thereafter, the device 1 0 and the container 20 are lifted, normally by crane. The frame part 12 includes four lifting lugs 40 for this purpose. The device 10 and the container 20 are lifted to position the container over an opening in the hold of the cargo ship and the cylinders are activated to rotate the gear wheel 15 and thus to rotate the frame parts 1 3 and the container 20. The device 10 and the container 20 are suspended over the opening rather than being placed on the surface of the cargo ship. Material within the container 20 can commence discharge from the container as soon as the container starts to rotate, depending on how full the container is and how flowable the material within the container is. Figure 1 also illustrates a container lid removal mechanism 45 which is operable to lift a container lid 42 from the container 20 to allow discharge of the contents from within the container 20. The lid 42 might not always be employed, but the use of a lid 42 is recommended for many materials which are sufficiently fine to form dust that can result in airborne particles which can pollute surrounding areas. The container lid removal mechanism 45 is supported between the span members 36 and is operable to lift a container lid from a container prior to the container being rotated through the sequence of rotation illustrated in Figures 2 to 4. For clarity, the container lid is not illustrated in Figures 2 to 4, but reference will be made to Figures 5 to 8, which show the container lid removal mechanism 45 separate from the frame part 1 2.

Referring to Figure 5, the container 20 is illustrated including a lid 42. The lid 42 is fixed to the container 20 by latches 43 which are provided on each long edge of the lid 42 and complementary latch parts are fixed to the adjacent surface of the container 20. The latches 43 are relatively simple hand operated latches which secure the lid 42 to the container 20 and which advantageously prevent material from within the container 20 from exposure to wind and rain etc. This has the advantage of quarantining material within the container 20 from being blown out of the container. When a container 20 is to have its contents discharged by the discharge device 10, the latches 43 are manually released, so that while the lid remains in position a shown in Figure 5, it is no longer locked in place to the container 20. Thus, the lid 42 remains in place on the container under its own weight. With the latches 43 unlatched, the container lid removal mechanism 45 can be moved to the extended condition shown in Figure 5. That movement is initiated via a pair of hydraulic cylinders 46, which extend between a plurality of articulated legs 47, which are each articulated at a midpoint 48. Extension of the cylinders 46 opens the removal mechanism 45 in a scissor-type movement to the position shown in Figure 5, while retraction of the cylinders 46 collapses the mechanism 45 to the position shown in Figures 1 and 6.

With the removal mechanism 45 fully extended as shown in Figure 5, cylinders 49 can be activated to shift lifting lugs 50. Activation of the cylinders 49 causes the lifting lugs 50 to shift from the disengaged position shown in Figures 5 and 7, to the engaged position shown in Figures 6 and 8, in which the lifting lugs engage the lid 42. In the position shown in Figures 6 and 8, the lifting lugs 50 engage within tine openings 51 of the lid 42 and when the removal mechanism 45 is contracted as shown in Figure 6, by retraction of the cylinders 46, the lid 20 is lifted away from the opening of the container 20. The container 20 can then be rotated for discharge of the contents within it. Thus, removal of the lid 42 from the container 20 is a simple and quick operation, by activation in the correct order of the respective cylinders 46 and 49.

The tine openings 51 are provided in the lid 42 so that it can be lifted and transported by a forklift vehicle, for example when the containers are being filled with material at the mine site. Thus, the tine openings are provided not just for the lifting lugs 50 to engage, but rather, are already part of the lid 42 and are a convenient point for engagement of the lid by the removal mechanism 45.

With reference to Figures 2, 3 and 4, it will be appreciated that the lid 42 has been lifted away from the container 20 prior to the container 20 being rotated through 180° to the position shown in Figure 4. As that rotation takes place, the lid 42 is maintained in close proximity to the span assembly 35 of the frame part 12 and therefore the lid does not hinder rotational movement of the container 20 or discharge of the contents of the container 20.

After the container 20 has been rotated to discharge its contents, it is returned to the upright position shown in Figure 2 and the cylinders 46 are again activated to lower the lid 42 into position relative to the container 20. The cylinders 49 are then activated to release the lifting lugs 50 from the tine openings 51 and then the removal mechanism 45 can be retracted to the position shown in Figure 1 , leaving the lid 42 closing the container 20 under its own weight. The latches can remain released while the container is returned from above the opening in the cargo ship hold.

The container 20 is fixed to the frame parts 13 via a simple latching arrangement which is illustrated in detail in Figures 9 and 10. Those figures shows the respective frame parts 1 3 from the inside thereof and displaced from the facing arrangement they assume which is shown in Figures 1 to 4.

A latching arrangement 55 is associated with each of the frame parts 13 and the arrangement 55 includes an elongate bar 56, which is connected to a spindle 57 at each end. The spindle 57 extends through end members 58 of the frame parts 1 3 and includes a head 59 which defines a lip 60 (visible in Figure 9 only). The head 50 is intended to be accepted within openings 61 formed in upper ends of the corner posts 62 of the container 20 (see Figures 5 and 6). The openings 61 are shaped to define an undercut (not visible in any of the figures) that mates with the lips 60 when the spindles are rotated from the position shown in Figure 9 to the position shown in Figure 10. Rotation of the spindles 57 thus causes the spindles 57 to lock within the openings 61 . With all four of the spindles 57 locked in this manner, the container 20 is secured to the respective frame parts 1 3 and can be lifted with the discharge device 10.

Rotation of the spindles 1 5 is by movement of the bar 56 and in the arrangement illustrated in Figure 9, this is achieved by the use of hydraulic cylinders 54 (which are only just visible in Figure 9 but which can be seen in Figure 1 ) and the use of an over- centre spring 63. The spring 63 thus applies a load in each of two directions depending on which side of its centre it is positioned and therefore it maintains the head 59 of the spindles 57 either in the container disengaged position shown in Figure 9, or the engaged position shown in Figure 10.

Figures 9 and 1 0 show a panel 64 of each of the frame parts 1 3 which is a strengthening panel to increase the stiffness of the frame parts 13. The panels 64 extend the full height of the frame parts 13. The use of the panels 64 can eliminate the need for bracing bars extending between the frame parts 13.

Figures 1 1 and 12 show a look arrangement for locking the frame parts 13 in the position of Figure 2, so that a container that is lifted by the discharge device 1 0 can be maintained in the Figure 2 position until such time as rotation of the container is required. The lock arrangement includes a latch 70 that is pivotable between the locked position of Figure 1 1 and the unlocked position of Figure 12. The latch pivots about the pivot 71 and is driven to pivot by the pneumatic ram 72.

The latch includes an arm 73 that has a recess 74 to receive a pin or projection 75. The recess is such as to accept the pin or projection 75 by rotation only. With the latch 73 in the position shown in Figure 1 1 , the frame part 1 3 is locked against rotation. When rotation is required, the ram 72 is withdrawn and the latch shifts away from the pin or projection 75 to allow the frame parts 1 3 to rotate.

The discharge device 10 is intended for operation with containers that have been delivered to a port via road or rail transport and the device is intended to be lifted by crane to engage a container which is resting on the delivery vehicle. Once the container is engaged by the frame parts 13, both the container and the discharge device 10 can be lifted to position the container to overly an opening in the hold of a cargo ship. In that position, the cylinders 46 and 49 are activated in the manner described above to lift the lid 42 from the container 20 (if a lid is provided) and thereafter, the cylinders 14 are activated to rotate the gear wheel 15 and thus the frame parts 1 3, to rotate the container 20 through the sequence shown in Figures 2 to 4 for discharge of its contents. The removal mechanism 45 also includes a power pack support comprising plates 65 (see Figures 1 to 4). The plates 65 present a surface for a power pack such as a hydraulic power pack to be fixed to.

It will be appreciated that the process of using the discharge device 10 as described above can contain the contents of a container up until the contents are to be discharged into the cargo hold. This differs significantly from the current process of discharging the container contents into a large body which is open to the elements and conveying material from the body on an open conveyor to the opening in the cargo hold. The present invention is considered to be significantly more environmentally friendly than that prior art method. In addition, the method and apparatus of the present invention is not considered to increase loading time to load a cargo ship and in fact could contribute to faster loading times.

The invention described herein is susceptible to variations, modifications and/or additions other than those specifically described and it is to be understood that the invention includes all such variations, modifications and/or additions which fall within the spirit and scope of the present disclosure.