This invention relates to an apparatus and method for removing the contents from closed containers.

There are various circumstances where automated removal of the contents from previously sealed containers may be required. For example, in the brewing industry, beer sold in cans is typically returned by retailers or distributors to the brewing or canning company if it remains unsold beyond the specified "shelf" life for the beer. It is then necessary for the beer to be removed from the sealed cans, either for reprocessing and reblending into fresh beer or volume measurement prior to disposal and waste whereby previously levied excise duty can be reclaimed. The same applies to canned beer returned for failing to meet quality standards and under-filled cans which should not reach the retail outlets.

Previous methods of contents removal are crude and labour intensive.

One method is to feed cans on a conveyor to a piercing/crushing device, having spiked rollers or punches, which pierce the can side-wall in various places so that the beer can drain out to a collecting trough below under the influence of gravity. Problems with such methods are that the beer tends to become contaminated with dirt, pieces of shredded can, or yeast spores from the air (which are often present in a brewing environment) . The removed beer must therefore be thoroughly filtered if intended for reprocessing, which complicates the process. Furthermore, cans are most commonly returned on the shrink-wrapped cardboard trays they were originally supplied on, and if these are fed into a crushing device there is a tendency also for pieces of cardboard and plastic to end up in the beer. Can piercing/crushing machines of this type also have a tendency to jam, meaning that the machine must be

permanently watched and manned. The rate at which cans can be emptied by this method is also very limited.

Viewed from one aspect, the invention provides apparatus for removing the contents of closed containers, comprising a plurality of tubular spears, means for conveying a plurality of containers into a position for engagement with respective said spears, actuating means for engaging the spears with the containers so that the free end of each spear pierces a container wall and thereby extends into the contents of the container, suction means communicating with the spears for removing the contents from each container via the spears, and means for conveying the empty containers from the apparatus.

Viewed from a second aspect, the invention provides a method for removing the contents of closed containers, comprising conveying a plurality of containers into a position for engagement by a plurality of tubular spears, moving said spears into engagement with the containers so that the free end of each spear pierces a respective container wall and thereby extends into the contents of the container, removing the contents of each container via the spears by suction means, and conveying the empty containers away from the spears.

The invention provides an improved, readily automated apparatus and method for emptying closed containers which is particularly applicable to removal of liquid contents such as beer from cans, but may have applications to other containers and contents, e.g. plastic cartons, bottles, powdered and viscous contents etc.

In the context of beer removal from cans, a far higher throughput of cans for emptying may be accomodated with greater reliability as compared with known methods, whereas the risk of contamination of the removed beer e.g. by can or plastic fragments, dirt or yeast spores is substantially reduced.

The wall of the container which is pierced by the spear may be the top wall in the case of a can or may be a closed lid or sealed lid attached to a container, such as a bottle, jar or carton, provided that the lid is ^• formed of a piercable material e.g. sheet metal or plastics.

The free ends of the spears are preferably formed into a spike-like configuration for easy penetration of the container walls, and are preferably moved by the actuating means so as to be located closely adjacent the bases of the respective containers when the suction means is actuated to ensure that all the contents are removed. The actuating means may then be operated to remove the spears from the cans before they are conveyed from the apparatus.

A particularly advantageous embodiment of the invention for use with cans of e.g. beer supplied in packs or trays is adapted simultaneously to empty a plurality of cans whilst still in such pack or tray, the spears being arranged in an array which matches the relative positions of the cans in the pack or tray and the conveying means being adapted automatically to locate successive packs or trays beneath the spears in position for engagement thereby in use.

The spears can then pass through any shrink wrap packaging material extending over the cans and penetrate the cans via their top walls. This enables a particularly high emptying rate to be achieved in the case of cans of beverage which are typically returned still in their original packs or trays.

The spears may pass cleanly through the cans and wrapping without pieces of metal and plastic being introduced in the removed beer.

A preferred embodiment of the invention further comprises means for crushing the containers after the contents have been removed therefrom. In a preferred such embodiment the actuating means includes a carriage

for the spears which is arranged for vertical reciprocal movement, and the means for crushing the containers after emptying comprises a crushing member coupled to the carriage and movable downwardly with respect to the carriage to crush the cans after the contents have been removed. The carriage and crushing member are preferably actuated by hydraulic or pneumatic cylinders under microprocessor control.

The preferred suction means for removing the contents comprises a pneumatically operated vacuum pump, although other pumping means may be used. The suction means is preferably also operated under micro-processor control. In a preferred embodiment, a carriage for the spears is provided with a manifold or manifolds communicating therewith, the manifold(s) being connected to a sealed storage tank for receiving the removed contents. The suction means may be connected to an upper region of the tank so that when operated it creates a sharp pressure drop in the tank which causes fluid from the containers to be drawn up through the spears and into the tank.

A preferred embodiment of the present invention will now be described by way of example only, with reference to the accompanying drawings, in which:

Fig.l is a partly schematic front elevation of a can emptying apparatus in accordance with the present invention;

Fig.2 is a perspective view from above of part of the apparatus of Figure 1;

Fig.3. is a sectional view taken along line III-III of Figure 2; and omitting certain parts for clarity;

Fig.4. is a sectional view similar to that of Figure 3,

but showing the apparatus in the piercing position;

Fig.5 is a sectional view similar to that of Figure 3 but showing the apparatus in the de-cant position;

Fig.6 is a sectional view similar to that of Figure 3 but showing the apparatus in the crush position; and

Fig.7 is a diagramatic diagram showing the connection of the apparatus to a suction means and storage tank.

Referring to Figs. 1 and 2, apparatus for removing the contents of sealed containers such as beer cans has a base 12 on which is mounted a conveyor belt 14 for conveying successive trays of cans across the base 12. A second conveyor belt 14a, upstream from said conveyor belt 14 and connected thereto holds a queue of trays of cans to be emptied, and conveys successive trays onto said conveyor belt 14. Once the cans have been emptied and crushed they are transferred onto a third conveyor belt 14b, connected to said conveyor belt 14 in a downstream position, to be conveyed away from the apparatus. A carriage 16 is mounted above the base 12 and is reciprocally moveable upwardly and downwardly relative to the base 12. The carriage 16 is supported above the base 12 by means of a first pair of hydraulic actuating cylinders 18, and movement of the carriage 16 is guided by four guide bars 20 extending upwardly from the base 12 and passing through apertures 22 near the corners of the carriage 16.

A crushing member 24 is reciprocally moveably mounted intermediate the base 12 and the carriage 16. The crushing member 24 is supported from the carriage 16 by means of a second pair of hydraulic actuating cylinders 26, and is guided in a similar manner to the carriage 16 by the guide bars 20 which pass through apertures 28

near the corners of the lower carriage 24. Hydraulic power is supplied to the system by a hydraulic power pack 15 located beneath the conveyor belt 14.

A plurality of tubular spears 30 extend downwardly from the carriage 16, and pass through respective apertures 32 in the crushing member 24. The number and positions of the spears 30 match the arrangement of the cans on the tray, such that a spear can be positioned over each respective can in use. The free end 34 of each spear 30 has a spike-like configuration which is able to pierce the top of the respective can. The carriage 16 is moveable by means of the cylinders 18 between a raised or start position (shown in Figure 3) in which the free ends 34 of the spears 30 are clear of the tops of the cans, and a lower or de-cant position (shown in Figure 5) in which the free ends 34 of the spears 30 are located inside the cans closely adjacent the bases thereof. Fences 36 are retractably clamped to the base 12 along each edge of the conveyor belt 14, to correctly position the tray of cans underneath the array of spears. Referring to Figs. 3 to 6, a crushing block 25 is attached to the bottom of the crushing member 24 such that in operation, its position corresponds to the position of the tray of cans. The crushing block 25 also has apertures 27 through which the respective spears 30 may pass.

Referring now to Fig.7, a sealed storage tank 38 communicates with the spears 30 via a fixed manifold 40 connected to the spears 30 via flexible hoses (not shown) . A micro-processor controlled vacuum pump 42 is connected to an upper region of the tank 38. Three level probes, namely a low level probe 44, a high level probe 46 and an emergency level probe 48 extend into the tank 38 through its top, each probe extending further into the tank 38 than the next. A cleaning fluid sprayball 50 also extends into the tank 38 through its top wall.

One cycle of operation of a preferred embodiment of the present invention will now be described:

A tray of cans to be emptied is carried by the conveyor belt 14 across the base 12 of the apparatus 10 until it is correctly situated below the array of tubular spears 30. The correct lateral positioning of the tray is ensured by the fences 36 which can be adjusted to accommodate different sized trays. Longitudinal positioning is achieved by halting the conveyor 14 under the control of the microprocessor in response to a sensor (not shown) arranged to detect when the tray reaches the desired position. As shown in Fig.3, in the start position the carriage 16 is raised and the crushing member 24 is supported below the carriage 16 at such a distance therefrom that the free ends 34 of the spears 30 extend as far as the lower surface of the crushing block 25.

Once the tray is in position, the first pair of hydraulic cylinders 18 is actuated to move the carriage 16 downwards. During this movement, the crushing member 24 is held in fixed relationship to the carriage 16 until the lower surface of the crushing block 25 comes into contact with the tops of the cans.

Referring now to Fig.4, the fences 36 are retracted and then the hydraulic cylinders 18, are further actuated so that the carriage 16 moves down further,- causing the free ends 34 of the spears 30 to protrude through the bottom of the crushing block 25 and to pierce the tops of the cans. The carriage 16 continues to move downwards, until the free ends 34 of the spears 30 are adjacent to the bottoms of the cans. During this movement, the second hydraulic cylinders 26 are allowed to contract so that the crushing block remains resting on the top surface of the cans. The apparatus is then

in the de-cant position as shown in Fig.5.

The micro-processor (not shown) then commands the vacuum pump 42 to operate, causing a sharp pressure drop in the tank 38. This sudden pressure drop causes the beer in the cans to be drawn up through the spears 30, via the manifold 40, into the tank 38. The vacuum pump is de¬ activated after a predetermined time when the cans are empty.

The second pair of hydraulic cylinders 26 is then actuated to move the crushing member 24 downwards relative to the carriage 16 such that the crushing block 25 flattens the cans as shown in Figure 6. The carriage 16, and crushing member 24 are then raised by the first hydraulic cylinders 18 to the start positon and the crushed cans are carried away by the conveyor belt 14 for disposal or recycling.

In order to clean the system, a dummy tray of cans containing cleaning fluid is emptied in the same way as hereinbefore described. Cleaning fluid is thereby sucked through the system and the sprayball 50 is also operated to spray cleaning fluid around the inside of the tank 38. The cleaning fluid is then drained from the tank 38.

The three level probes 44, 46, 48 extending into the tank 38 through its top surface, monitor the level of beer in the tank 38. The tank 38 is normally emptied automatically when the level of beer reaches the level of the high level probe 46, with the emergency probe 48 providing a back-up against over filling. The beer from the tank can be transferred to a reprocessing plant, or can be measured for excise duty purposes before being discharged as waste.

Although the above-described cycle of operation includes crushing the cans after they have been emptied, it should be appreciated that whilst this is an advantageous feature in many applications, the emptying feature of the present invention can be provided independently.