NZ332000A - Bulk container has a conveyor and movable side wall or floor means - Google Patents

Abstract

A transportable bulk material container (10) comprising flexible sidewalls (16), movable sidewall members (11), a floor (14), a bulk material conveyor (15) located on said floor (14) and an exit frame (13). In operation the sidewall members (11) can be independently pivoted about exit frame (13) by an actuator (12) to raise or lower the respective flexible sidewalls (16). To reduce the fall of material during loading the sidewall members (11) are lowered and then raised as the container (10) fills. During unloading of material via the bulk material conveyor (15), the sidewall members (11) are raised to tighten the flexible material to form a "V" shape, with the bulk material conveyor (15) being at the bottom of the "V". A turtle back may be suspended between the sidewall members (11) to reduce loading on the bulk material conveyor (15).

Description

No: 332000 Date:23 September 1998 NEW ZEALAND Patents Act 1953 COMPLETE SPECIFICATION IMPROVEMENTS IN TRANSPORTATION I, GRAEME FRANCIS LUKE SMITH a New Zealand citizen of Warrens Road, R D 2, Marton, New Zealand do hereby declare the invention, for which I pray that a Patent may be granted to me, and the method by which it is to be performed to be particularly described in and by the following statement I 23 DEC 1999 I I Received I This invention relates to improvements in transportation but more particularly a container for transportation of bulk goods.

When transporting bulk goods such as potatoes, carrots or other vegetables in a large container from the field to the processing plant, damage can often occur during loading and unloading.

Using potatoes as an example, damage occurs at first instance due to the falling height of the potato from the harvester conveyor to the floor of the bulk container. Secondary damage occurs during unloading where there is friction between the potatoes as they are removed by a conveyor in the container. Existing transportation containers are often in a V-shape cross-section with a conveyor positioned along the bottom of the V. In this way potatoes are removed from the bottom of the pile out through a door in the wall of the container. The concentrated weight of potatoes above the conveyor causes bruising on the potatoes being removed.

A third source of damage occurs at unloading via the conveyor described above as the conveyor is often still at a height above ground and further falling bruises the potato. 21/12/99 3 Damage to the vegetables has a serious effect on quality of the end product and high rejection rates may result.

The problem presently existing is in the lack of careful handling of the product during loading and unloaaing. Therefore, the object of the present invention is to provide a bulk container which facilitates careful handling and hence has less detrimental effect on the product.

Additionally, present fixed V-shaped containers have a high centre of gravity and are thus unstable, particularly on uneven or transversely sloping ground.

It is a further object of the invention to provide a bulk container with a relatively low centre of gravity which can still transport a comparable load to known containers.

In one broad aspect of the invention there is provided a bulk container including at least one side wall capable of movement wherein at least part of said side wall is constructed from a flexible material. 2-/12/99 The invention will now be described with reference to the accompanying drawings which illustrate a preferred embodiment of the invention in which:- Figure 1 is a general perspective view of a bulk container according to the present invention, Figure 2 is a schematic elevation view of the container in 'normal" position.

Figure 3 is a schematic elevation view of the container in 'loading" position, Figure 4 is a schematic elevation view of the container in 'unloading" position, and Figure 5 is a perspective view from within the bulk container according to the present invention.

The bulk container 10 as best seen in its entirety in Figure 1, is mainly comprised of two side wall frame members 11 which are actuated by four hydraulic rams 12 and pivotally mounted to a forward and rearward frame 13.

Located on a base frame 14 is a central conveyor belt arrangement 15 for conveying product within the container 10 through an opening in forward frame 13. Connected 21/12/99 between the edge of conveyor 15, the frame 13 and the side wall frame members 11, is a flexible material 16 forming the remainder of the container walls.

Preferably the flexible material 16 completes the container construction in a conventional rectangular shape as seen m Figure 2.

A second articulated conveyor 17 located at the forward end of Figure 1 may swing up to serve as a door for the opening in frame 13. In use, conveyor 17 acts as a ramp transporting product upward or downward from the container 10 for further processing. It is preferable that conveyor 17 be provided with side walls (not shown in the drawings) to ensure that product leaving container 10 does not spill onto the ground. In addition to side walls on conveyor 17, corresponding walls may extend from frame 13 to ensure there are no gaps during unloading through which product may fall through.

The container's hydraulic power is operated from a control box 18 which may independently activate the pairs of hydraulic rams so each wall frame 11 is separately movable.

Figures 2 to 4 illustrate the intended method of use of the bulk container 10. 2i/12/99 6 Figure 2 shows the container in its normal 'fully loaded" transport mode where the side wall frame members 11 are substantially aligned (parallel) with the base frame 14. The_ bulk container 10 in this position offers the greatest volume for storage of product within the flexible walls 16. Product in the centre of the container may be piled above the height of the side wall frames 11 and still be transported safely with adequate stability.

It should be noted that when empty, the container would generally travel with frame members 11 in fully lowered position. This avoids flexible walls 16 'flapping" about and causing irritation to a truck driver during transit.

Figure 3 shows the container being side-loaded via the conveyor C of a harvester (for example) . The right side wall frame member 11 has been lowered about a first pivot Pi. Lowering of frame member 11 causes flexible wall 16 to sag and enables entry into the container possible from a lower level than an equivalent fixed side wall container. It will be appreciated that as the container 10 fills with product (the opening in frame 13 being closed, of course) the frame member 11 may be raised to its previous position as in Figure 2. 21/12/99 Both side wall frame members 11 are pivotable about points Pi and P2 respectively and therefore either side of the container may be loaded at one time by virtue of the independent control of the hydraulic power source (not illustrated in Figures 2 to 4). Alternatively, if there were two input sources (such as conveyor C in Figure 3) then both frame members 11 may be lowered.

Figure 4 illustrates unloading of product from the container 10 via conveyor 15 in the centre of base frame 14. Those skilled in the art may recognise that this configuration of the container 10 corresponds to conventional fixed V-shape storage/transport bins which incorporate a central conveyor.

In Figure 4, both side frames 11 can be seen to be raised in order to let product fall by gravity toward conveyor .

The position represented by Figure 4 is, in fact, only the position of the container at substantially the final stage of unloading. Unloading begins with the container in the configuration of Figure 2 when the conveyor 15 is activated (the opening in frame 13 being opened) and product begins to exit the container via conveyor 17 (Figure 1) . 8 Only the product (e.g. potatoes) located substantially in the central column of the container (above conveyor 15) are removed initially and the force acting on product being removed at the bottom of the container (at conveyor 15) is only influenced by those potatoes directly above.

When the central 'column" of potatoes has been cleared, one or both side frames 11 may be raised to coax potatoes onto the conveyor 15. Ultimately, the container will appear as seen in Figure 4.

Figure 5 illustrates a perspective view of inside the container 10 where a 'suspended turtle back" 20 is included as a means of reducing static pressure on conveyor 15 during start up (for unloading) .

Turtle backs are known in the art for this purpose. Particularly, the use of a turtle back means less stress is placed on the conveyor when unloading begins because it effectively separates the product load and reduces the product force acting on the conveyor.

However, the additional advantage of the turtle back 20 illustrated is in its ^suspended' nature. Specifically the corners of turtle back 20 are connected via chains 21 to the movement of side frames 11. Therefore as frames 11 rise during unloading, so too does the turtle back 20, 21/12/99 allowing an increasing amount of product to fall underneath.

An additional frame 22 for connection of turtle back 20 by chains 21, located at a midpoint of the container separates the load into two sections. Preferably the turtle back 20 is positioned to the rear half of the container, i.e. away from the opening in frame 13 (not seen in Figure 5) for unloading at conveyor 17.

The gradual rising of the side walls by virtue of pivoting frames 11 and the flexible material 16 allow controlled exit of potatoes in a manner which does not cause excessive damage. Preferably the control box 18 will have an 'automatic" setting whereby the hydraulic rams 12 are activated incrementally during unloading dependant on the load remaining in the container 10. Setting the bin to unload automatically reduces the need for supervision.

The automatic lifting feature is based upon comparing the pressure drop in the hydraulic circuit to a preset spring valve. Specifically, as the conveyor 15 removes product from the container 10 via conveyor 17 the pressure in the hydraulic circuit drops (because there is less force required to drive conveyor 15) . As it drops below the preset spring valve pressure the rams 12 are activated 2 /12/99 momentarily to raise side walls 11. Immediately as the pressure in the circuit rises the fluid pressure to rams 12 is bypassed and the sides 11 cease rising until the circuit pressure once again drops below the preset value.

The above process of automatically raising sides 11 is very gradual and is hardly noticeable to the casual observer.

The construction of the present invention offers particular advantages over existing V-shaped containers with fixed sides (similar in appearance to Figure 4 except the top edge of the container would be horizontal) where the entire weight of the load is concentrated upon the conveyor 15 and the potatoes exiting the container.

Also, V-shaped containers of comparable volume have a much higher centre of gravity comparable to the 'full" container illustrated in Figure 2. As the container reaches the state of Figure 4 the centre of gravity does not rise significantly as the load is being continually removed.

The bulk container of the present invention is considerably more stable during transport and at a stand still on uneven ground (or sloping hillsides) than a conventional fixed V-container. 21/12/99 11 The container 10 of the present invention may be produced in different scales.

The particular embodiment illustrated by Figure 1 is mounted on the back of a truck and forklift holes 19 are provided for relocating the unit mounted on base frame 14.

Further embodiments may be produced for smaller scale trailer-top use.

The main frame construction is preferably produced from galvanised steel. The flexible sides 16 or 'curtain" of the present embodiment are manufactured from Nylon PVC reinforced by weldable webbing.

It will be appreciated that a number of modifications or adaptations may be made to the bulk container without departing from the scope or the spirit of the invention as it was intended.

The bulk container of the present invention thus provides an effective and easy to use construction which minimises damage to product during loading and unloading. 21/12/99 12 Furthermore, unloading using the controlled movement of the flexible/pivoting side walls provides a much more even product feed from conveyor 17. This aspect aids workers who must pack, e.g.. potatoes, into standardised packages. A consistent flow of product is highly desirable in this case. 2 /12/99

Claims (21)

13 / WHAT I CLAIM IS:

1. A bulk container including side walls, a floor means, a conveyor means located on or m said floor means, and an exit means, wherein at least one side wall is capable of movement and at least part of that same side wall is constructed from a substantially flexible material.

2. The bulk container of claim 1 wherein the side wall includes a frame means, and the flexible material hangs from the frame means and is fixed substantially to an edge of the conveyor.

3. The bulk container of claim 1 or 2 wherein the side wall is pivotally mounted for raising and lowering to a main frame of the bulk container.

4. The bulk container of claim 3 wherein the raising and lowering of the side wall is controlled by a linear actuator.

5. The bulk container of any one of the preceding claims wherein, as a side wall moves, the flexible material becomes taught, creating a gradient toward the conveyor.

6. The bulk container of any one of the preceding claims wherein a secondary conveyor is provided at the exit means.

7. The bulk container of claim 6 wherein the secondary conveyor is pivotably mounted to be able to form a closure to the exit means. 21/12/99 14

8. The bulk container of claim 6 wherein the secondary conveyor provides a ramp from the exit means.

9. The bulk container of any one of claims 6 to 8 wherein the secondary conveyor has side walls.

10. The bulk container of any one of the preceding claims wherein two opposing side walls of the bulk container are arranged for movement.

11. The bulk container of claim 3 wherein two opposing side walls of the bulk container are arranged for movement and when both walls are fully raised, the flexible material is substantially taught and forms a *V" shape, the conveyor being located at the bottom of the "V".

12. The bulk container of claim 10 or 11 wherein the movement of the two opposing side walls is independently operable.

13. The bulk container of any one of the preceding claims wherein the moving side wall is arranged for automatic raising and/or lowering.

14. The bulk container of any one of the preceding claims wherein a turtle back is provided substantially suspended between two opposing side walls of the bulk container.

15. The bulk container of claim 3 including a turtle back substantially suspended at at least one end between two opposing side walls arranged for pivotal movement, and wherein raising the side walls causes said turtle back to rise proportionately. 21/12/99 15

16. The bulk container of claim 14 or 15 wherein the turtle back is suspended over the conveyor and extends only over a portion, e.g. half of said conveyor.

17. The bulk container of any one of the preceding claims wherein apertures are provided on a main frame of the bulk container for receiving the forks of a lifting vehicle.

18. The bulk container of any one of the preceding claims wherein the flexible material is nylon PVC reinforced by weldable webbing.

19. The bulk container of any one of the preceding claims wherein said container is mounted on a chassis with wheels (as a trailer unit).

20. The bulk container of any one of the preceding claims wherein said container is mounted on a vehicle.

21. The bulk container substantially as herein described with reference to the accompanying drawings. GRAEME FRANCIS LUKE SMITH By his Attorney DON HOPKINS & ASSOCIATES ' t-, j, c.jy jfr-'Q OF IV Z. ! 2 5 ScP 2:E9 i1 I