BACKGROUND OF THE INVENTION It is conventional practice in plant nurseries to place plants in small containers once they have reached a certain specified size. The potting operation is achieved with the aid of a simple hand potting bench or a commercially available potting machine. These are usually situated in a dedicated potting shed. After the potting operation is complete, the pots are loaded onto a trailer either singly or by placing several pots into a plastic tray that is then loaded onto the trailer. When the trailer is fully loaded it is towed to the growing area in the nursery by a small tractor or other vehicle. The potted plants are then unloaded from the trailer and placed either on benches or onto the ground in the growing area. In some instances the pots are positioned so that they are all touching one another but in many cases they are spaced apart to allow for an increase in size as the plants grow.

Pots that are placed on the ground are normally arranged in blocks (or bays) with a typical length of 8-30m and a width of 1.2-1.5m with narrow walkways of say 0.3m between adjacent blocks.

In some cases the potting bench or potting machine is mobile and these can be positioned adjacent to where the re-potted plants will be placed in the growing area.

It will be appreciated from the foregoing that the aforementioned conventional practice in plant nurseries involves manual loading of the pots onto the trailer and manual unloading of the pots and this was not only time consuming but labour intensive.

Reference may also be made to US Patent 6,056,497 which refers to a dump wagon for transporting potted plants from one location to another. The dump wagon includes a wagon bed that tilts between a horizontal transport position and a tilted or inclined unloading position. A pusher bar at one end of the wagon bed is movable towards the other end of the wagon bed to push potted plants off the wagon as the wagon is slowly moved forwardly. The pusher bar is chain driven and automatically disengages the chains when the pusher bar reaches the other end of the wagon bed and the unloading operation is complete. Side rails prevent the potted plants from falling off the sides of the wagon. These side rails are however movable out of the way for the purpose of loading the dump wagon.

Reference also may be made to US Patent 3,913,758 which describes another article handling system directed to potted plants where the potted plants are loaded onto pallets which in turn are loaded onto wheeled carts and moved to supporting racks in a greenhouse. The pallets are then transported from the carts to the racks. The carts and racks each have parallel roller tracks spaced at a predetermined distance for the pallets to roll upon. The pallets each have cylindrical runners on the bottom thereof in parallel spaced relationship to ride in the parallel spaced tracks of the carts.

The pallets can be slid from the carts to the support racks and back onto the carts. A plurality of carts may be pulled by a single vehicle which can stop at marked locations for unloading a plurality of pallets onto a plurality of spaced and marked off support racks for each stop of the towing vehicle.

While US Patent 6,056,497 simplifies unloading of potted plants from the dump wagon by the chain driven pusher, it will be noted that it is still necessary to load the dump wagon manually. Also the provision of the chain driven pusher bar makes the dump wagon relatively expensive to manufacture.

The handling system described in US Patent 3,913,758 is highly specialised requiring that the carts and racks have parallel rollertracks and that the pallets require cylindrical runners in parallel relationship to be movable on the carts and racks. Again this system is relatively expensive

and is restricted to operation in a greenhouse.

SUMMARY OF THE INVENTION It is an object of the invention to provide an article handling system which is simple and effective in operation and at least reduces one or more disadvantages of the prior art.

The invention in one aspect provides an article handling system for loading small articles onto a vehicle which transports the articles to a desired location, such as a growing area. The articles may be loaded onto the article handling system from an adjacent location. In relation to potted plants, the adjacent location may be, for example, a hand potting bench, a growing area containing potted plants, a potting machine or a mobile potting bench.

The article handling system of the invention includes: (i) a conveyor assembly for conveying articles from a location remote from the vehicle ; (ii) a carriage movable along the conveyor assembly; and (iii) a guide element attached to the conveyor assembly or located adjacent thereto, which guides articles onto a loaded deck or surface of an adjacent vehicle.

The carriage may be provided with lateral indexing means so that the carriage may stop at spaced intervals along the conveyor assembly.

The guide element may be a deflector element attached to the carriage, which may deflect potted plants laterally off the conveyor apparatus and onto the loading deck or surface of the adjacent vehicle. The deflector element may be mounted to the carriage so that the deflector element may be set at an adjustable angle relative to the direction of travel of the carriage. This angle may be selected so that an optimum position may be selected to ensure a smooth transition of movement of the potted plant from the conveyor apparatus to the vehicle.

The carriage may comprise one or more rollers or wheels and more preferably one or more pairs of rollers or wheels which may move in guide tracks of a conveyor frame or body. Preferably, the deflector element

such as a deflector bar is releasably and adjustably attached to the carriage.

A side of the carriage adjacent to the vehicle may be provided with a micro switch fitted with a sensor bar or rod which is an example of the lateral indexing means described above. There also may be provided end indexing means, which in one form, may comprise a pair of sensors which are each located on an adjacent end of the carriage to determine when the carriage reaches one or both ends of the conveyor assembly. When a sensor contacts a limited switch or mating contact, the carriage may then reverse its motion.

The carriage may be provided with a suitable drive means such as a chain or belt drive whereby a sprocket mounted on the carriage rotatably engages with an endless belt or chain driven by a drive motor mounted on the conveyor apparatus. The chain or belt drive may also be provided with a braking mechanism if required. Alternatively, the carriage may be provided with a drive motor on the carriage, which drives the rollers or wheels though a suitable transmission.

The conveyor apparatus may suitably comprise a belt conveyor driven by any suitable drive means such as an electric motor and associated gear box which drives a driven roller located at one end of the belt conveyor.

The other end of the belt conveyor may be provided with an idler roller. The conveyor apparatus may also have a body or frame having the aforementioned guide tracks and support legs located at each end of the belt conveyor to allow the vehicle to pass under a return side of the conveyor belt and between the support legs.

The conveyor body or frame may also include a fixed lateral projection or bar attached to one side thereof which allows a movable bed of the vehicle to have an end part which may rest on the fixed projection or bar so that articles may be efficiently transferred from the conveyor belt to the movable bed.

In another aspect of the invention, there is provided a trailer for transporting small articles such as potted plants, which has a trailer frame or support frame and a tray pivotally mounted on the support frame and

movable with respect to the support frame so that the movable tray is tiltable at either end of the support frame for unloading or loading purposes as may be required.

The moveable tray or bed may be provided with one or more wheels or rollers movable in guide tracks located on the support frame.

There also may be provided fixed idler rollers between the movable bed and the support frame.

There also may be provided locking means to maintain the movable bed or tray in a tilted position for loading or unloading. The movable bed may be formed from spaced bars, slats or wire mesh such that the surface of the movable bed reduces friction to a minimum. The bars or slats may be spaced apart to allow any surplus potting media from potted plants to fall through to the ground.

The movable bed may also be provided with a plurality of vertically arranged plates, guide rails or bars so that there are provided a multiplicity of lanes on the movable bed for location of the potted plants in linear rows.

The tilting means for tilting of the movable bed relative to the support frame may be of any suitable type such as a pneumatic ram assembly or hydraulic ram assembly interconnecting the support frame and the movable bed. More preferably, there is provided an upright tilting lever which is rigidly attached to a rotatable bar or axle located transversely on the support frame. There also may be provided a strut interconnecting the rotatable bar and the undersurface of the movable bed. At a free end of the strut there may be provided one or more guide rollers movable in an adjacent guide track located on the undersurface of the movable bed.

The trailer of the invention may be located adjacent to the loading system as described above whereby an open end of the movable bed may be located proximal to the conveyor belt so that potted plants may be transferred onto the separate lanes of the movable bed as described in the illustrated embodiments of the invention hereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS Reference may now be made to illustrated embodiments of the invention wherein: FIG. 1 is a perspective view of the article handling system of the invention located adjacent to the trailer of the invention for loading purposes ; FIG. 1A is a similar view to FIG. 1 showing an alternative embodiment; FIG. 2 is a perspective view of the trailer of the invention; FIG. 3 shows a side view of the movable bed of the trailer in a loading position; FIG. 4 shows the movable bed of the trailer in a transportation position; FIG. 5 shows the movable bed of the trailer in an unloading position; FIGS. 6A and 6B show one example of use of the trailer of the invention in conjunction with the conveyor system for loading of potted plants from a potting machine; FIGS. 7A and 7B show similar views to FIGS. 6A and 6B showing loading of potted plants from a hand potting bench; FIGS. 8A and 8B show a plan view and side view respectively of a trailer of the invention unloading potted plants in a growing area; FIGS. 9A and 9B show a plan view and side view respectively of unloading potted plants in required spacing using a trailer of the invention; FIGS. 10A and 10B show unloading of potted plants using the conveyor system of the invention and a tiltable deck; FIGS. 11A and 11 B show unloading of potted plants using the conveyor system of the invention on movable decks; FIGS. 12A-D, FIGS. 13A-D and 14A-D show three different mechanisms used for spacing of pot plants as they are unloaded from the trailer; FIG. 15 illustrates another embodiment of the invention; and

FIG. 16 is an end elevation of the embodiment of FIG. 15.

DETAILED DESCRIPTION OF THE DRAWINGS In FIG. 1, reference is made to an article handling system 10 of the invention which is specifically directed to pot plants 11 which are shown being transferred by conveyor apparatus 12 including conveyor belt 13 and conveyor body 14. Conveyor belt 13 is driven by driving roller 15 by a drive motor (not shown) and pot plants 11 are deposited onto conveyor belt as shown by the arrows in full outline. The pot plants 11 are transferred onto a movable bed 18 of an adjacent trailer 16 by diversion or deflector bar 17 to direct pot plants 11 into an adjacent lane 19 as shown. A first lane 19 has already been occupied with pot plants 11. Each of lanes 19 are bounded by side plates 20 and pot plants 11 travel on slider rods 21. Each of side plates 20 are mounted in support rods 22. The trailer 16 also includes side rails 23.

Diversion bar 17 is attached to a carriage 24 which is mounted for movement on conveyor body 14 as shown, wherein carriage mounts or side members 25 and 26 are mounted for slidable movement on conveyor body 14 in unison with carriage mount or side member 27. Carriage mount 25 includes a sensor bar 28 which senses when carriage 24 reaches the end of its travel on conveyor body 14 at the end 29 by contact with a suitable stop or limit switch (not shown). Carriage mount 26 includes a sensor bar 30 which detects when carriage 24 reaches the end of its travel at the other end of conveyor apparatus 12 (not shown). Attached to mount 25 is angle adjustment mechanism 31 for diversion bar 17. Angle adjustment mechanism 31 includes plate 32 attached or integral with diversion bar 17.

There is also provided pivot bolt 34 which interconnects plate 32 and adjustable plate 35 and which when in a non fastened position permits pivotal movement of bar 17 about a vertical axis. There is also provided adjustment bolt 36 which extends through adjustment slot 37 to interconnect plate 32 and adjustment plate 35. There is also provided plate 33 which is rigidly attached to carriage mount 25.

At the other end of diversion bar 17 there is provided plate 39 rigidly attached to bar 17 which is connected to slotted plate 40 by pivot bolt

41A provided with nuts 41. Slotted plate 40 is rigidly attached to carriage mount 27. There is also provided a sensor rod 42 and associated micro switch 52 which works in conjunction with electric eye 42A, reflector42B and ray 42C for detecting when lane 19 has reached its maximum in relation to the number of pots 11 which can occupy lane 19. There is also provided a linear adjustment mechanism 38 for micro switch 52. Adjustment mechanism 38 includes adjustment plate 44 having a lower part 44A adjustably attached to slot 45 of plate 40 by bolts 45A. Vertical part 46 of plate 44 is provided with a pair of slots 47 through which extend adjustment bolts 48. These bolts 48 extend through slot 49 of adjacent plate 50 to which is attached micro switch 52 which has boss 51 attached thereto for supporting vertical sensor rod 42. Sensor rod 42 is attached to boss 51 by clamp 54 which facilitates height adjustment of sensor rod 42 relative to clamp 54.

Details of the mounting of carriage 24 to body 14 of conveyor apparatus 12 are shown in FIG. 1, wherein each of mounts 26 and 27 are interconnected by strap 26A having rollers 26B. In similar fashion strap 26C interconnects mount 25 and opposite mount 25A. There is thus formed an undercarriage 25B having rollers 26B located in guide tracks 12A of body 14 best shown in FIG. 3.

In FIG. 1A there is shown a modification of the invention, wherein adjustment mechanism 31 is removed and deflector element 17 comprises part of a pneumatically operated cylinder or air cylinder 85 which is attached to carriage 24 by appropriate attachment means (not shown).

In FIG. 2 there is shown the structure of trailer 16, which comprises a movable bed 18 shown in phantom for supporting pot plants 11.

Movable bed 18 includes lanes 19 shown in FIG. 1. Moveable bed 18 has a pair of opposed mounting rollers 62 which are each located in guide tracks 63 of a trailer frame 64 located below movable bed 18. Rollers 62 are attached by brackets 65 to movable bed 18. Trailer frame 64 also includes cross members 66 and 67 as well as bearing rollers 68 mounted in housings 69 which are attached to guide tracks 63 which are each in the form of

channels as shown. Rollers 68 bear against the underside of movable bed 18 when it moves relative to trailer frame 64. There is also provided tilt control lever 69 which is attached to transverse bar 70 which is rotatable relative to support frame 64. Bar 70 is rotatably mounted to support frame 64 by bearings 71.

Transverse bar 70 also has attached thereto a strut 72 having a pair of guide rollers 73 which are each located in guide channel 74 attached to the underside of movable bed 18. Transverse bar 70 is also provided with an arcuate locking plate 75 having a curved slot or groove 76 which engages with locking pin 77 having handle 78. Locking pin 77 is in the form of a locking nut which engages with a mating threaded bolt (not shown) to lock plate 75 in position as desired.

Trailer frame 64 also includes pivot joints 79 interconnecting each cross member 66 and 67 to adjacent axles 80 which are attached to ground engaging wheels 81. This enables trailer frame 64 to pivot relative to axles 80 when required as shown in FIG. 2. There is also provided draw bar 82 attached to trailer mount 83 by connection bracket 84.

In operation when movable bed 18 reaches one extremity of its movement relative to support frame 64, rollers 62 each engage a stop (not shown) and thus tilting of support bed 18 relative to trailer frame 64 may be initiated as shown by movement of control lever 69. When the desired degree of tilt has been obtained, locking pin 77 locks arcuate plate 75 in position. There is also provided bracing strut 85 which interconnects each of wheel axles 80 to control pivoting movement of wheel axles 80 relative to trailer frame 64.

Loading of trailer 16 by conveyor apparatus 12 is also shown in FIG. 3, wherein pot plants 11 are loaded onto trailer 16 by diversion or deflector bar 17 shown in FIG. 1, forcing pot plants 11 into a selected lane 19 of movable bed 18. The movable bed 18 is in a loading position being tilted to trailer frame 64 as shown in FIG. 2, wherein control lever 69 is locked into position. Each of pot plants 11 may slide down a selected lane 19 under the influence of gravity. There also may be provided vibrators (not shown)

attached to bed 18 to facilitate the sliding of pots. Such vibrators may be operated by electro magnetic induction.

FIG. 4 shows transport of pot plants 11 with movable bed 18 shown parallel to or being in parallel planes with trailer frame 64 and locked in the horizontal position by control lever 69. Mounting rollers 62 are shown located intermediate the ends of each of their respective guide tracks 63.

There is also provided a guard plate or stop 64A engaging with the first pot plant 11.

FIG. 5 shows unloading of trailer 16, whereby pot plants 11 may be placed on the ground 86 with movable bed 18 having reached an unloading position, whereby each of mounting rollers 62 engage an adjacent stop (not shown). The movable bed 18 is locked in position by control lever 69. Stop 64A is lowered as shown to allow pots 11 to be unloaded as trailer 16 moves forward.

In FIGS. 6A and 6B there is shown one example of the article handling system 10 of the invention in operation. This example includes a potting machine 10A that transfers re-potted plants onto conveyor belt 13.

The deflector bar 17 directs the pots 11 onto movable bed 18 of trailer 16 with the bed 18 in the tilted position as shown. When one full row of pots is loaded in a respective lane 19, the carriage 24 (not shown in FIGS. 6A or 6B) and deflector bar 17 indexes along the conveyor belt 13 automatically. The carriage 24 comes to rest in the correct position and the next row of pots is loaded. This procedure is repeated until the bed 18 is fully loaded. At this stage the deck of pots is lowered into the horizontal position and the loaded trailer 16 towed forward by means of a small tractor. Any number of trailers 16 (up to say four for example) can be attached as shown and as one trailer 16 is fully loaded and is moved forward, the next empty trailer 16 is positioned for loading. When all the trailers 16 are loaded they are towed to the growing area where the pots are placed either onto benches or onto the ground.

In FIGS. 7A and 7B reference is made to another example of the invention in practice, using a hand potting bench 10B. The trailer 16 is

positioned as shown with the bed 18 in the tilted position. Worker are positioned on each side of the trailer 16 as shown and as the re-potting operation is completed each pot 11 is placed on the tilted bed 18 of the trailer 16 in a required lane 19. It is preferable to work from the centre of the trailer 16 and move progressively towards side rails 23 and placing pots in lanes 19.

When a trailer 16 is fully loaded, it is towed forward by means of a small tractor and an adjacent empty trailer 16 is moved into position for loading. The construction of the hand potting bench is such that it allows passage of the trailers 16 underneath the top of the bench. When all the trailers 16 are loaded, they are towed to the growing area where they are unloaded.

In FIGS. 8A and 8B each individual loaded trailer 16 is reversed into position in the growing area and the bed 18 tilted downwards as shown. The tractor is then driven forward and the potted plants 11 unloaded in a semi-automatic fashion such that they are deposited on the ground unspaced as shown.

In another embodiment shown in FIGS. 9A and 9B, a similar arrangement is shown as in FIGS. 8A and 8B, except that the potted plants 11 are deposited on the ground spaced as shown. Pots 11 can also be placed so that each alternate short row can be displaced (offset) sideways to form a staggered pattern if required.

In an alternative embodiment as shown in FIGS. 10A and 10B, a mobile potting machine is positioned adjacent to the growing area as shown. In this application a belt conveyor 13 extends from the potting machine to almost the full length of the growing area bays as shown. A pot plant unloading device 86 is arranged at 90° to the belt conveyor 13 as shown.

This device is similar to trailer 16 described previouslywith the addition of a narrow, light-weight, sloping deck section 87 attached to the indexing carriage 24 and deflector bar 17. Individual potted plants 11 travel along the belt conveyor 13 from the potting machine and are deflected

sideways onto the conveyor section 88 of the unloading device 86 and then deflected onto the narrow sloping deck section 87. The pots 11 are deposited onto the ground and the combined deck section 87, indexing carriage 24 (not shown) and deflector bar 17 moves the appropriate distance along the short belt conveyor 13 so that the next pot 11 is placed on the ground in the correct position.

When one complete short row is filled the unloading device assembly indexes along towards the potting machine so that the next row of plants is placed on the ground in the correct position. This system is capable of placing the pots unspaced, spaced or staggered.

In FIGS. 11A and 11B there is shown an alternative pot plant handling system 1 OB which is a mobile bench system. Empty decks 90 of a mobile bench system are positioned as shown on parallel guide rails 89 such that the surface of the decks 90 slope at an angle sufficiently great to allow potted plants 11 to slide down the slope for loading purposes. Potted plants from the potting machine (or optional mobile potting bench) are directed onto the belt conveyor 13 as shown. On reaching the end of the belt conveyor 13 the pots 11 proceed to slide down the sloping deck 90. The pots 11 are guided in a straight line by a guiding arm 91 on one side as shown and on the other side by the existing previous row of pots. (Initially the surround of the deck acts as a guide).

When one complete row is loaded the deck is indexed along to enable the next row of pots to be loaded. When each deck is fully loaded it is moved into the growing area. This can be achieved using a mono-rail system or similar.

A number of different mechanisms can be used for spacing of plants as shown in FIGS. 9A and 9B. Operating examples of three such versions of the spacing mechanism are shown in FIGS. 12-12D, FIGS. 13A- 13D and FIGS. 14A-14C.

FIGS. 12A through 12D show the operation of the first version.

The specialised trailer 16A is. positioned in the area potted plants are to be unloaded to the ground (FIG. 12A). Each of the guiding bars

20 on the movable support 18 used to hold the potted plants in rows is expanded longitudinally to increase the distance between the centres of potted plants. When the desired distance is obtained the guiding bars are fixed in their new position and the movable support 18 is tilted and fixed in the unloading position. An extension 20A of the guide rails 20 captures the first row of pots to slide down the movable support 18 and holds them in an offset position (FIG. 12B). The movement of the trailer 16A along the growing area releases the first row of pots and changes the offset of the guide bar extension 20A as shown. The next row of pots slides down the trailer deck and is held in the new offset position of the guide bar extension 20A. The process is repeated as the trailer 16 travels across the ground unloading the potted plans in a staggered pattern onto the ground (FIG.

12D).

FIGS. 13A through 13D show the operation of the second version.

The specialised trailer 16A is positioned in the area potted plants are to be unloaded to the ground (FIG. 13A). The position of the long rows of potted plants (down the movable support 18) assumes a fan shape as the distance between pot centres at the edge of the trailer 16A is increased while the guide bars 20 pivot from the other end of the trailer.

When the desired distance between pot centres is obtained the guiding bars 20 are fixed in their new position and the deck is tilted and fixed in the unloading position. An extension 20A to the fanned guide rails 20 captures the first row of pots to slide down the trailer deck and holds them in an offset position (FIG. 13B). The movement of the trailer along the growing area released the first row of pots and changes the offset of the guide bar extension 20A as shown. The next row of pots slides down the trailer deck and is held in the new offset position of the guide bar extension 20A (FIG.

13C). The process is repeated as the trailer travels across the ground unloading the potted plants in a staggered pattern onto the ground (FIG.

13D).

FIGS. 14A through 14C show the operation of the third version.

The specialised trailer 16A is positioned in the area potted plants are to be unloaded to the ground (FIG. 14A). The movable support 19 is tilted and fixed in the unloading position. A concertina mechanism 20B under the edge of the trailer 16A captures the first row of pots to slide down the movable support 18 (FIG. 14B). The movement of the trailer along the growing area expands the distance between pot centres held by the concertina to the desired distance and the potted plants are released onto the ground (FIG. 14C). The next row of pots slides down the trailer and is held in the folded concertina mechanism. The process is repeated as the trailer travels across the ground unloading the potted plants in a staggered pattern onto the ground.

FIG. 15 shows another variation of the invention, wherein conveyor 13A is provided with a deflector bar 17A, which is pivotable from a position shown in bold outline to a position shown in phantom. This enables pot plants to be deflected off either side of the conveyor. The deflector bar 17A may be pivoted through an angle of about 90° by air cylinder 85 shown in FIG. 1A.

The embodiment of FIG. 15 makes it possible for a potting machine to continue to operate during the period in which a fully loaded trailer is being replaced with an empty one. Less than two seconds is available to divert the flow of pots from one trailer to another at typical pot filling speeds.

Thus, trailers can now be loaded on both sides of the conveyor.

This facilitates the uninterrupted flow of pots during the change over of trailers by allowing the pots to be deflected to a trailer on one side of the conveyor whilst a previously loaded trailer is being replaced by an empty trailer on the other side of the conveyor. An appropriate operating sequence will now be described.

At the commencement of loading of pots 11 onto the transportation vehicle (ie. the trailer 16D), the deflector element 17A is set to deflect pots 11 to the row on the trailer furthest from the pot supply source 92. Once this row is completed (ie. row A), the deflector element 17A

moves quickly towards the pot supply source 92 and stops at the required position to deflect pots into the next row to be filled (ie. row B). As each row is filled, the deflector element 17A is again indexed by the lateral indexing means shown in FIG. 1A towards the pot supply source 92 until all rows on the first trailer 16D are filled (ie. rows C, D, E, F and G). As soon as the first trailer 16D is fully loaded with pots 11, the deflector element 17A travels quickly and faster than the speed of the pots on the conveyor 13 carried by carriage 24 back to the commencement position (ie. end 93 of conveyor 13) and, at the same time, pivots so that it will now deflect pots to the trailer 16E positioned on the other side of the conveyor 13A. Whilst the second trailer 16 is being loaded, the first trailer 16 is removed and replaced with an empty trailer.