The invention concerns a device for opening boxes especially boxes containing blocks of frozen fish and similar products.

Much of the catch of deepwater fish either is filleted and frozen in blocks whilst at sea or this is done at a landing facility. The freezing is done in waxed cartons which are firmly stuck to the fish product when frozen.

The boxes of frozen fish are then transported to users, such as a fish-food plant for processing. To date such boxes are cut open by hand. This is a risky, labour-intensive task where accidents are frequent because of the high work tempo and the use of knives .

Purpose :

The main purpose of the invention is the design of a device to open such boxes. The apparatus must be automatic so that operatives are unnecessary and it must satisfy certain general operative criteria such as low maintenance, reliable opening, suitable operating tempo and a low rate of product waste. Furthermore, it must be simple to feed a product into the device, which is to automatically transfer both the product and the packing material to the subsequent loading and disposal f ci 1ities .

Principle:

The basic principle and protection provided are indicated in Claim of Patent 1. Other details about the invention are stated in the subsidiary claims. The invention will be explained in more detail with reference to one means of design.

Exaπtp1e: The invention is described below with specific reference to the illustrations, where:

Fig. 1 shows a frozen block of fish produce packed in a cardboard box,

Fig. 2 is a schematic presentation of a unit in accordance with the invention from a vertical perspec¬ tive,

Fig. 3 is a more detailed vertical perspective of the supportive structure of a unit in accordance with the invention, Fig. 4 is a vertical perspective of the operative parts of the feed section of the unit in Fig.3,

Fig. 5 shows an equivalent vertical perspective of the mid-section of the unit in Fig. 3,

Fig. 6 shows a vertical section through the outlet section with the drive rollers,

Fig. 7 is a more detailed vertical section of the separation blades in Fig. 6, whilst

Figs. 8-9 present alternative means of designing the elements in the above figures. Details and structural elements which are irrelevant to a presentation of the principle have been omitted from the above figures.

In Fig. 1 a flat block of fish 11 is shown which is parallelpiped with a rectangular cross-section. This is enclosed on all sides by a box with overlapping

flaps at the end 12 and equivalent overlapping side flaps 13 along one of the sides. The box consequently has an unbroken side edge 14 and unbroken top and bottom surfaces 15. Fig. 2 sketches the main components of the device in the example. This consists of a feed section 21 for cutting and/or opening the sides, a mid-section 22 for opening the end flaps and an outlet section 23 for the removal of the cut parts of the boxes. There is a pusher 24 following the outlet section 23, which transfers the blocks of fish to the next processing stage and an output unit 25 which feeds the cut-up boxes into a pile 26. The various parts of the device will now be described in more detail. Fig. 3 shows the feed section 21 in a frame structure 31 with a pneumatic cylinder 32, indicated schematically, which is for transporting the blocks of fish 11 (not illustrated). The operative parts of the feed section 21 are omitted in Fig. 3 but are shown in detail in Fig. 4.

The mid-section 22 consists of a frame 33 with parallel sidewalls which run at right angles in relation to the axis of feed section, so that the blocks of fish can be pushed across from the feed section to the mid-section 22. There is a second hydraulic cylinder 34 which is for transporting the fish along the mid-section. The operative components in the mid-section 22 are illustrated in Fig. 5.

The outlet section 23 consists of a frame 35 which is at right angles to the the mid-section, in other words parallel to the feed section 21. There is a third longditudinal hydraulic cylinder 36 which is centrally located on the frame 35 for transporting the blocks of fish from the mid-section to an outlet position 37. There is a fourth hydraulic cylinder 38 at right angles to the side walls for pushing away the

unpacked blocks of fish 11. At the free end of the piston rods on each of the hydraulic cylinders it is indicated that there is a pusher (not illustrated) and cylinders are connected to a drive and control system for the sequential feeding of blocks of fish. At the end of the outlet section 23 there is a powered output unit 25 for removing the remains of the boxes. These details will be described in greater detail with reference to Figs. 6 and 7 which also show details of the mechanism that separates the parts of the boxes from the blocks of fish.

Fig. 4 shows details of the operative components in the feed section 21.

The blocks of fish 11 initially come into contact with an L-shaped blade 41 which is supported in a vertical axis. The operative part of the blade 41 protrudes into the path of the side edge 14 so as to cut open the lateral side, whilst the other part of the blade is held in an active position by a spring 42. The blade 41 is positioned on the side edge so that it only makes a wide lateral flap.

Immediately trailing the blade 41 is a wedge 43. This is made of a steel bar with a point that protrudes into the path of the blocks of fish, though the leading edge of the wedge 43 is at a slight angle to the main axis of the feed section, which is the direction the blocks of fish are moving. The purpose of the wedge 43 is to open up the flap on the block of fish 11 that is formed when the side edge 14 is cut. The wedge 43 is shaped in a loop back towards the blade 41 , so that the end 45 acts like a probe that registers the edge of the block of fish 11 and adjusts the position of the wedge accordingly. In the downstream direction of movement the wedge is extended by a sprung guide section 44 linked to a locking point 46.

On the opposite side and slightly downstream of

the point of the wedge 43 in the direction of movement is an equivalent wedge set 47 and 48, where the downstream wedge 48 is positioned behind the upper wedge 47. These two points of the wedges are mounted about at the same height, however wedge 47 is designed so that it bends the lower flap downwards. In an equivalent way, wedge 48 is designed to bend the upper flap upwards. Wedges 47 and 48 have a common looped probe 49 which is similar to one already described above. The probe 49 has the same function of gauging the width of the block of fish 11 and thus holding the points of the wedges in the correct position to bend out the flaps 13.

Fig. 5 illustrates two equivalent pairs of wedges, 51 and 52, and 53 and 54 respectively. These open up their respective end flaps 12 (Fig. 1). These wedges are also equipped with probes 55 and 56. The assembly elements have not been included as they would make the basic concept more difficult to grasp. When the fish box reaches the mid-section 22, the box around the block of fish 11 has been divided in two and all the side flaps have been folded out. The only remaining function to complete the unpacking is removing the parts of the box from the block of fish. At the transition between the mid-section 22 and the outlet section 23 there is a separation mechanism 61 (not illustrated in Fig. 3) but illustrated in Fig. 6. The separation mechanism consists of upper and lower divider blades 62 and 63 respectively. These are mounted above one another and can be rotated on a support 64.

Fig. 7 shows a more detailed illustration of the divider blades 62 and 63. Each of these has an edge 71 which is in two parts, the leading part of the edge 71 which slopes outwards from the middle to a tip 72 on the outer edge. The leading part of the edge 71 is

almost parallel to the incoming surface of the box 15, so that the tip 72 is pointed at the gap between the block of fish 11 and the surface of the box 15. Both edges 71 and 72 are connected to an arm 73 which is made of the same sheeting material as the edge part 71. The arm 73 continues in the direction of movement of the blocks to a common axle 74. Both the arms 73 are joined to the axle by a sleeving 75 which can rotate on the axle. The ends of the axle are in supports 64, these could be protruding brackets, for example.

The arms 73 with the edge 71 on the divider blades 62 and 63 are sprung to face inwards, i.e., a downward facing end position for blade 62 and an upward facing end position for blade 63. As a block of fish in its sliced box passes the blades 62 and 63, the various parts of the box will be removed from the fish, the upper section being carried over axle 74 and the lower section is led under an equivalent lower support axle 76. The design of the guide plates 65 and 66 will ensure that the parts of the box are led away from the output unit 25.

The output unit 25 consists of upper and lower pairs of drive rollers 67 and 68 respectively, the axes of which are parallel to the support axes 74 and 76 for the blades 62 and 63.

The pairs of drive rollers are located in the vertical mid-plane in the path of the fish blocks in the outlet section 23, in the same vertical path as the third cylinder 36. There is at least one roller connected to an axle 69 in each pair of drive rollers 67,68. This axle 69 is connected laterally to a drive motor (not illustrated). The components may be best placed at the side of the outlet section 23, close to the fourth cylinder 38. A collection space 77 for the remains of the boxes is made at the run off from the drive rollers 67,

68. Apart from the components that have been described, the unit also contains a number of mechanical details and a control system that is not described here. It is unnecessary to expound on these details to understand the invention and its design.

A device in accordance with the invention can be incorporated into a processing line and equipped with temporary storage facilities both in the feed and outlet sections. Thus the device can be operated independently of the supply rate and the subsequent processing of the fish.

A device in accordance with the invention can also be used for removing similar cardboard packing material from other goods, such as cases containing deep-frozen goods. In another simpler means of design the unit can be used for removing cylindrical packing material .

The pneumatic cylinders can be replaced by other drive mechanisms, hydraulic or electromechanical. In an alternative design the wedges 47, 48, 51,

53, 54 can be designed as indicated in Fig. 8A-D with a common wedge 81, a probe unit 82 and a split guide unit with an upper and lower bar-shaped element 83 and 84 respectively. Fig. 8 also shows an attachment bracket 85 and an adjustment screw 86 for the probe.

Fig. 9A-B shows an alternative means of designing a cutter 91 for cutting away the lower part of a box. Here the support 92 is modified in relation to the above example since it has an internal spring 93 which keeps the cutter tensed in an upward position.

Fig. 10A-C shows an alternative design of a cutter 101 for cutting away the upper surface of a box. Here there is a blade 102 with an appropriate probe 103 which can be adjusted by a screw 104 this is firmly held by a stopper 105. There is also a lug 106 that extends out of a surrounding housing 107.