BACKGROUND ART Shipping containers are ideal in transporting, storing and unloading goods, as the containers are extremely robust, large, and have standard dimensions and sizes which makes them easy to transport, lift, stack and store. However, transportation of bulk powder or granula products in shipping containers has presented a problem with the unloading of the product. Bulk powder or granular products means that the material is not bagged but is merely poured into the container without internal linings, equipment or fittings. Emptying such products from the container has met with several problems including slowness in emptying, and difficulty in accessing all parts of the inside of the container. Also, bulk powders such as cement powder must not contact atmospheric moisture, and most current unloading devices do result in the container contents being exposed to the atmosphere for a considerable period of time.

In remote and inaccessible areas, larger concreting jobs may require bulk cement powder to be stored for appreciable periods of time without becoming unusable. Silo's and the like to store and dispense cement powder are not warranted for remote jobs due to the expense in setting up.

Bulk bins can be used, but repeated opening of the bins to remove set quantities of the powder can cause deterioration of the powder remaining in the bin. Transportation to site and dispensing cement powder also presents difficulties.

OBJECT OF THE INVENTION The present invention is directed to an apparatus which can unload bulk containers in a manner which may overcome the abovementioned disadvantages or provide the public with a useful or commercial choice.

In one form the invention resides in bulk container unloader comprising a support platform adapted to support a bulk container which has an outlet, a hopper associated with the outlet to receive content passing through the outlet, and means to tilt the container to allow the container contents to move by gravity into the hopper. The container may be a shipping container. The hopper may tilt with the container. The support platform and the means to tilt the container may form part of a trailer.

In another form, the invention resides in a bulk container unloader comprising a support platform adapted to support a shipping container, a hopper having an open end which is sealable relative to an outlet in the container and having a discharge outlet, and means to tilt the shipping container with the attached hopper to allow the container contents to move by gravity into the hopper.

The outlet can comprise one or more doors in the end, floor, or elsewhere in the container.

In another form, the invention resides in a bulk container unloader comprising a first support platform adapted to support a shipping container the platform having a horizontal platform portion on which the container can sit, and a vertical end frame portion at an outlet of the container and which extends about the door end of the container and can be sealed thereto, a second support platform on which the first support platform can be supported, locking means to lock the container, the first support platform and the second support platform against movement relative to each other, a hopper having an opening, or open end which is sealable against the vertical end frame or a door frame and having a discharge outlet, and means to tilt the shipping container with the attached hopper to allow the container contents to move by gravity into the hopper.

The outlet may be the door end of the container.

The apparatus will allow a shipping container filled with bulk powder such as cement powder to be emptied in a manner where little or no contact with the atmosphere occurs, and the bulk powder need not be emptied all at once. That is, the bulk powder can be discharged from the

hopper on an as needs be basis, making the apparatus ideal for on-site delivery of cement powder or other powder or granular products.

The shipping container can be of normal sizes and dimensions and it is known to have shipping containers of different sizes, all of which may be applicable to the present invention. Of course, while a shipping container is a preferred bulk container, the bulk container may consist of other than a shipping container if such a container can be made conveniently.

The apparatus has a support platform on which the shipping container can be supported. The support platform can be made from steel beams or sections. If desired, the support platform can be sized to accept from the smallest to the largest containers, or if only one sized container will be used, the support platform can be made to support only one size of container.

A hopper is provided which has an open end which can be an open top which is sealable relative to the outlet which can be a floor door and/or an end door of the container. That is, shipping containers are provided with two steel swing doors on one end wall and in one form of the invention, the hopper has an open top or open end which is dimensioned to seal around this area such that the bulk powder or granular products in the shipping container are not unduly exposed to the atmosphere. Various types of sealing means can be provided. For instance, the hopper can be provided with a pneumatic or inflatable seal which seals about the outlet of the container, which can be a floor outlet or an outlet in the end wall of the container, or about the portion of the container through which the bulk material will flow. Other types of sealing means are envisaged.

The hopper has a discharge outlet such that material flowing into the hopper can be passed through the discharge outlet. The outlet can be of conventional type and can be made closeable when not in use to separate the material as much as possible from the atmosphere.

The hopper may have means to assist in passing the material towards the discharge outlet. The means may include conveying means, such as a screw conveyor, an airslide, and/or paddle, or combinations thereof

which assists in collecting the material passing into the hopper and conveying it towards, and possibly though, the discharge outlet.

A pump or similar device can be provided to convey material discharged from the outlet of the hopper to some distance away. For instance, the pump can be used to pump the material into a storage bin. The pump can be a peristaltic pump, vacuum conveyor, venturi, auger or belt, or other device to transfer the product to its destination.

The apparatus includes means to tilt the shipping container such that the container contents can move under gravity into the hopper.

In one form, the container can be tipped with the outlet, such as the open end, or floor mounted door of the container remaining in sealing communication with the hopper. In another form, the container is locked to the support platform, and the support platform is pivoted between an inclined tipping position and a substantially horizontal rest position. The tipping can be achieved using a ram, such as an hydraulic ram, although it is envisaged that other mechanisms can also be used, such as chains, winches, motors, and the like.

In order to assist placement of the container onto the support platform, one form of the invention has the container sitting on a first support platform. The first support platform with the container can be rolled, lifted, or otherwise placed onto a second support platform. The first support platform has a horizontal platform portion on which the container can sit and this can be in the form of a steel frame arrangement. As well, the first support platform can have a vertical end frame portion at the door end of the container and which can extend entirely about the end of the container such that the vertical end frame portion can have a pair of vertical members extending along each side wall of the container and an upper horizontal inter- connecting member extending over the top wall the container. The vertical end frame can be sealingly engaged to the surround of the container and this can be achieved using various sealing means such as pneumatic or inflatable seals, stuffing, flaps, sealing rings, and the like.

The first support platform may have lower wheels or rollers to

allow it to roll onto the second support platform. Rails or tracks may be provided to assist in this action. Preferably, the container and the first support platform can be lifted onto a truck and then moved adjacent the second support platform and rolled onto the second support platform.

The second support platform may have locking means to securely lock the first support platform to the second support platform against relative movement. It is also preferred that the shipping container is lockable to the first support platform, although it is envisaged that it can also be locked directly to the second support platform.

The hopper may have an open end which is sealable relative to the vertical end frame portion on the first support platform, and in this arrangement, a better seal may be achieved than if the shipping container was sealed directly against the hopper.

In one form of the invention, the hopper is dimensioned such that if the outlet of the container has openable doors (for instance a floor door or door on the end wall), the doors can swing open into the hopper while still allowing the container contents to pass into the hopper. With this arrangement, it is not necessary to open the container doors prior to contacting the container with the hopper, and this can again minimize contact of the container contents with the atmosphere.

A container door opening prevention means may be provided to prevent the container door (s) from opening too soon. That is, the container doors can be initially securely locked by locking rods extending over the door face, the rods being operated by a steel locking lever. Once the container is fitted to the hopper, the steel locking lever may be difficult to access or is inaccessible, and it is preferable that the lever can be opened and the locking rods disconnected prior to the container being fitted to the hopper. However, as this can also cause the container doors to open and spill the contents, it is preferred that a door opening prevention means is part of the apparatus such that when the doors are unlocked, the prevention means will stop the doors from swinging open until such time as the container is properly positioned relative to the hopper.

BRIEF DESCRIPTION OF THE DRAWINGS Embodiments of the invention will be described with reference to the following drawings in which Figure 1 is a side view of an apparatus according to a first embodiment of the invention and showing a shipping container spaced away from the hopper.

Figure 2 illustrates the apparatus of Figure 1 where the shipping container has been pushed against the hopper.

Figure 3 shows the apparatus in a tilted position and a horizontal position.

Figure 4 is an end view of the apparatus showing a vertical end frame portion extending about the door end of the container.

Figure 5 illustrates a second embodiment of the invention in plan view.

Figure 6 illustrates the apparatus of Figure 5 in side view.

Figure 7 shows the apparatus of Figures 5 and 6 in a tipping position.

Figure 8 illustrates a further embodiment where the apparatus is on a trailer making it portable.

Figure 9 shows a view of conveying means in the hopper of the apparatus of Figure 5.

Figure 10 is an end view of the embodiment of Figure 8 showing how the semi-trailer can be stabilized.

Figure 11 is a plan view of a trailer mounted apparatus according to another embodiment of the invention where the container has an outlet on the floor.

Figure 12 is an elevation view of the trailer of Figure 11.

Figure 13 is a perspective view of the trailer of Figures 11 and 12 and illustrating the container in phantom.

Figure 14 is another view of the trailer of Figures 11 and 12 and illustrating the container in a horizontal and tipped position.

BEST MODE Referring to the first embodiment illustrated in Figures 1 to 4, there is illustrated a bulk container unloading apparatus which broadly has a shipping container 10 supported on a two part support platform 11 and where the container can be moved into engagement with a hopper 12. Shipping container 10 is a conventional steel shipping container of rectangular construction and has a door end 13 on which two heavy steel swing doors are fitted (not shown). The doors can swing open by being attached to the remainder of the container through steel pivot pins. The doors can be locked in a closed position by vertical steel rods which extend over the outside of the door and into upper and lower parts of the container. A steel lever is fitted to the rods and can be lifted to unlock the rods and therefore allow the doors to open. These features are not illustrated and are perfectly conventional to shipping containers.

In Figure 1, container 10 is initially lifted onto a first support platform 14 which is formed from steel welded members and is made sufficiently strong to support a fully laden shipping container 10. Support platform 14 has lower rollers 15 to allow it to roll over second support platform 16. The rollers can roll over rails or tracks on second support platform 16 in order to facilitate movement of container 10 towards hopper 12.

In practice, container 12 is placed on first support platform 14 and is locked thereto typically through the usual twist locks. The container and the first support platform can then be lifted onto a semi-trailer for transportation to the bulk container unloading apparatus which forms part of the present invention. The semi-trailer can be reversed to adjacent the end of the apparatus and the shipping container with the first support platform can then be rolled from the semi-trailer onto second support platform 16. Of course, this is preferred only and other means to put container 10 onto the apparatus can be used.

First support platform 14 has a vertical end frame portion 17 adjacent the door end of the container. End frame portion 17 is better illustrated in Figure 4 and consists of a pair of vertically extending post

members 18,19 and a top horizontal member 20. Post members 18,19 and horizontal member 20 are dimensioned to extend about the outer wall of shipping container 10. Frame portion 17 is provided with a pneumatic seal 21 which can be pneumatically inflated to seal post members 18,19 and horizontal member 20 against the outer walls of shipping container 10 and adjacent door end 13. A second vertical end frame portion 22 can be provided on the other end of the shipping container 10 and this can be provided with a seal as well which allows the container to be placed on first support platform either way.

Second support platform 16 is formed from steel members sufficiently strong to support the weight of a fully laden shipping container and the first support platform. Second support platform 16 is spaced above the ground by foundations 23 with the spacing being approximately that of the height of a semi-trailer tray such that the shipping container 10 can be rolled from the semi-trailer and onto second support platform 16.

When shipping container 10 is on second support platform 16, the doors are kept shut by a door opening prevention means in the form of power operated secondary door locks 24 (see Figure 4). These door locks 24 are extended to prevent the container swing doors from swinging open. At this stage, the primary locks which form part of the container doors can be opened with the doors being prevented from immediately swinging open by secondary door locks 24 which form part of the apparatus.

Container 10 can now be moved forward against hopper 12.

Hopper 12 has an open end 25 against which the door end of the container can pass. Hopper 12 has a sufficient internal size to allow the container doors to swing open inside hopper 12 as the container is tipped upwardly.

The front face of the hopper has a surround frame 26 which is fitted with a pneumatic seal 27. As first support platform 14 is rolled over second support platform 16 and towards hopper 12, the end frame portion 17 will abut against frame 26 on hopper 12. At this stage, the first support platform can be locked to the second support platform against further movement and seal 27 can be pneumatically inflated to seal frame 27 against end frame portion 17.

Once in this position, the shipping container 10 can be tipped upwardly as illustrated in Figure 3 from its lower horizontal rest position to an inclined tipping position where the container is inclined at approximately 60°.

To achieve this, container 10 must be securely locked to first support platform, typically through twist locks and first support platform must be securely locked to second support platform also by twist locks. Also, the container frame may be locked onto the hopper. A hydraulic or pneumatic ram 29 (see Figure 3) which is pivotally attached to a portion of foundation 23 is extended to cause second support platform 16 to pivot about pivot pin 30 which is supported by foundation 23. As container 10 tilts upwardly, the secondary door locks 24 are disconnected and the container doors swing open by gravity as the container is tipped. The container can be tipped to approximately 65° which allows the bulk powder or granular product in the container to slide under gravity into the hopper. The hopper can have internal conveying means such as augers or screw conveyors (not illustrated) or airslides to convey the bulk material to the hopper discharge outlet 31. Outlet 31 can be fitted with a rotary valve, vacuum conveyor, venturi, auger or belt, or other device to transfer the product to its destination.

It can be seen that with this arrangement, the contents of the container can be metered out on an as-need-be basis and either immediately or over a prolonged period of time with little or no atmospheric contact. If the entire contents of the container are required, the container can be maintained in its tilted position and the contents metered therefrom through the hopper.

If only a portion of the contents are required, the container can be tilted to fill the hopper, the required contents can be discharged and the container can then be lowered back to the horizontal position. Although the container doors stay in the open position, the seal between the container and the hopper prevent atmospheric contamination.

Figures 5 to 7 illustrate a second simpler embodiment. In this embodiment, a base platform 35 is provided which can be made from steel section and onto which a shipping container (not illustrated) can be placed and locked in position using the usual twist locks 36. A vibrator 37 is fitted to

platform 35 and is spring loaded against the bottom of the container to assist in the movement of compacted product through the container and to clean the last of the product from the container.

A hopper 38 is provided adjacent the door end of the container.

The hopper is pivotally mounted about pivot pin 39 and can pivot clockwise (see Figure 6) to 45° to allow the hopper to swing away while the container is placed onto platform 35. A ram 40 is provided to swing hopper 38 away from and against the door end of the shipping container. When the container is on the platform, the hopper can be hydraulically tilted back in place to seal to the door end of the container. The hopper has an access door 41 which can be opened and which allows the container doors to be unlocked. A ram 42 extends through hopper 38 and is attached to the container doors to pull the container doors open and to hold the doors in position. (In a variation, the container has an horizontal hatch door behind the main container doors to prevent the powder from spilling out when the main container doors are opened, and ram 42 is attached to this hatch door to pull it open and to hold it in position).

A powerful hoist 43 is fixed to a sub-frame 44 and to platform 35 and allows platform 35 to be tipped upwardly at about 65° and as illustrated in Figure 7. In this tipping angle, the container contents can spill into hopper 38.

Hopper 38 has a cross auger 45 with left hand flights at one end and right hand flights on the other end and which rotates at slow revs keeping the product clear from the sides of the hopper and directed to the outlet 46 in the centre of the auger. A rotating paddle 47 in the centre of the auger keeps the product agitated and ensures constant feed through outlet 46.

Figures 8 and 10 show side and end views of a transportable apparatus which is mounted to a semi-trailer. Figure 10 shows the side support legs 48 to stabilize the trailer during the tipping process.

Figures 11-13 illustrate plan, elevation and perspective views of a bulk container unloader according to a further embodiment. The unloader comprises a trailer 50, which allows the entire apparatus to be made portable.

Trailer 50 has an upper support platform 51 to support a container 52 (shown

in phantom in Figure 13). At the rear of trailer 50 is a transversely extending hopper 53 having an open top. Inside hopper 53 are two counter-rotating augers 54,55 which will convey material towards a central lower outlet 56.

Outlet 56 communicates with the inlet 57 to a horizontally mounted peristaltic pump 58. The peristaltic pump 58 is of the type having a central rotor which presses against an internal flexible pump pipe. The peristaltic pump has an outlet 59 typically fitted with a coupling to allow various devices (such as conveying pipes) to be coupled thereto. The peristaltic pump pipe can be approximately 100mm in diameter and the rotor can rotate at approximately 32rpm. The pump is able to pump approximately 50 tonnes p/hour of the flowable material.

Attached to inlet 57 is a fluidising means 60 which is in the form of an air induction box. The box has an air inlet which is connected to a pressure hose and ultimately to a source of compressed air. The compressor supplies air at approximately 10KPa as a high volume low pressure source of air. The air passes into the induction box and into a longitudinal tube which has a nylon webbing on the top. The box has an outlet which is coupled to the pump inlet.

In use, the peristaltic pump is started which causes a suction to form at the inlet. High volume low pressure air is passed into the induction box and at the same time, the outlet 56 of the hopper is opened. The pump sucks material from the hopper outlet and into the air induction box, and as the solid material passes through the box, it becomes fluidised by the air and adopts an at least partially fluid nature. At this stage, pump 58 can efficiently pump the dry particulate matter through the pump and through outlet 59. A conduit (not shown) can be attached to the outlet to allow the material to be pumped into a holding tank, silo or to any other suitable destination. There is very little dust associated with the pumping and therefore large dust collectors are not required.

Container 52 in this embodiment has a door in the bottom floor of the container (not illustrated) which overlies the open top of hopper 53 when the container is supported on the trailer. The bottom door can be

opened such that powder initially falls through the door, into the hopper to be conveyed by augers 54 through outlet 56. As the container becomes partially emptied, it can be slowly tipped upwardly to allow more of the powder to fall through the open floor mounted door of the container. The hopper 54 also pivots with the container such that no appreciable air gap is formed between the two.

Figure 14 is another view of the bulk unloader showing a shipping container in a horizontal position and in an inclined tipped position.

It can be seen that hopper 53 is connected to the tipping chassis 62 and thus stays in a fixed position relative to the container 52 as the container is tipped.

It should be appreciated that various other changes and modifications can be made to the embodiments described without departing from the spirit and scope of the invention.