The present invention relates to an apparatus for laying down items, such as fish or fish fillets, into a liquid, such as a brine, in a container, comprising a conveyor having a stretch of a travelling supporting surface and a downstream end, the conveyor being designed so that at least a first conveyor part comprising said stretch of the travelling supporting surface and the downstream end can be moved forwards and backwards relative to the container.

In connection with, e.g., the salting of fish fillets, it is known to inject brine into the fillets in a brine injection machine, whereby the fillets are placed on a conveyor belt conveying the fillets past a brine injection station and to a downstream end of the conveyor belt. After the brine injection, the fillets are placed in a container or a vat with brine for curing. In prior art, the transfer from the conveyor belt to the brine takes place at least partially manually, the fillets being delivered, e.g., on a table from which one or two operators pick up the fillets one by one and place them layered in the vat in an estimated suitable pattern. During the entire work process, the operator has to change his or her working position several times for each fillet with movements comprising body twists and bends. Additionally, the fillets risk being damaged by the manual handling as they may break or receive pressure marks from fingers. GB-A-382 789 describes an apparatus for salting fish for curing.

The apparatus comprises an endless conveyor belt with a first stretch from a first upstream roller to a first downstream roller, whereupon the conveyor belt passes to a second upstream roller located below the first stretch. The conveyor belt has a second stretch from the second upstream roller to a second downstream roller, and from the second downstream roller the conveyor belt passes below the first and second stretches back to the first upstream roller. The first rollers are positioned with a mutual fixed distance, and the second rollers are positioned with a mutual fixed distance. However, the second rollers may be displaced forwards and backwards in the direction of transport of the second stretch. Above the first stretch and above the second stretch, respective salt dosing boxes are placed, and a rotary turning device is placed between the first downstream roller and the second stretch. The second stretch is horizontal, and the second downstream roller is placed at a distance above an empty vat. In use, fish first pass under the salt dosing box above the first stretch to be salted on one side. Thereupon, the fish are passed beyond the downstream end of the first stretch, i.e., over the first downstream roller in order to be turned by the rotary turning device and land on the second stretch, which passes the fish under the salt dosing box above the second stretch, whereby the fish are salted on the other side. The fish are then passed beyond the downstream end of the second stretch, i.e., over the second downstream roller, whereby the fish fall down into the vat. By moving the second rollers and thereby the downstream end of the second stretch forwards and backwards, the fish are distributed evenly in the vat. As the fish are tossed about when delivered from a conveyor stretch, this apparatus is only suited for dry salting and is not suited for laying down fish into brine. The object of the present invention is to provide an apparatus for mechanical transfer of items, such as fish or fish fillets, from a conveyor to a liquid or brine in a container.

This object is obtained by means of an apparatus of the type stated in the introduction, the apparatus being characterised in comprising a control device for coordination of a forward speed of the travelling supporting surface and a backward speed of movement of the first conveyor part relative to the container. Through coordination of the backward speed of movement and the forward speed of the travelling supporting surface so that they are substantially the same, but of opposite directions, items on the conveyor's travelling supporting surface in said stretch achieve a horizontal velocity substantially equal to zero, but the first conveyor part is removed under the items whereby the items are laid on the surface of the liquid or the brine in the container when that surface is closely below the downstream end. In this way, items, e.g., fish fillets, which are placed in a pattern upstream on a conveyor can be laid in layers in brine while maintaining such pattern.

In a preferred embodiment, the apparatus comprises a second, stationary conveyor part with a second stretch of a travelling supporting surface placed upstream of the first travelling supporting surface and having a second downstream end arranged immediately above the travelling supporting surface in the first stretch. This facilitates incorporation of the apparatus into, e.g., an existing brine injection machine comprising its own conveyor which does not necessary give room for the forward and backward movement of the first conveyor part.

Preferably, at least the first downstream end extends downwards in the downstream direction. This ensures a gentler and more accurate delivery of items closer to the surface of the brine or the first stretch of travelling supporting surface. As the first downstream end extends downwards in the downstream direction, both as concerns the upper side of such downstream end on which items are conveyed and the underside of the downstream end, the place where the items leave the conveyor and are transferred to the liquid or brine in the container can thus be brought closer to the surface of the liquid or brine.

In a preferred embodiment, at least the first downstream end comprises a chute extending in continuation of the stretch of the travelling supporting surface. In this way, the surface of the respective downstream end over which surface the items are conveyed may be brought even closer to the surface of the brine or the travelling supporting surface in the first stretch, which makes it possible to deliver items even more gently and accurately. In a practical embodiment, at least the first travelling supporting surface is constituted by a running belt. Thereby, the first and the second travelling supporting surfaces may be constituted by independent belts running over respective rollers. This makes it possible to adjust the mutual speeds of the two travelling supporting surfaces, and it is possible to use differently designed belts with different properties and surfaces.

The apparatus preferably comprises a carrier for at least one container, the carrier being designed to move and/or tilt the container. This makes it possible to arrange a container empty of items in the carrier, e.g., by means of a forklift truck, in one place and move the container into place under the downstream end of the first conveyor part by means of the carrier, and/or it is possible to tilt the container so that part of the rim of the container closest to the first conveyor part is lowered relative to an opposite part of the rim of the container so that the downstream end of the first conveyor part can be brought closer to the surface of the liquid or brine in the container.

In a preferred embodiment, the apparatus comprises a device for controlling a level of liquid in the container. In this way, the liquid level in the container can be kept constant while the container is being filled with items so that the distance between the surface of the liquid or brine and the downstream end of the first conveyor part is kept constant.

Preferably, a device for measuring a quantity of liquid removed from the container is provided in that respect. The volume of the quantity of liquid removed will be equal to the volume of items laid down into the brine when the level of the liquid surface is kept constant, whereby the quantity of liquid removed is a direct measure of the quantity of items laid down into the brine. In a practical embodiment, the device for controlling the level of liquid in the container comprises a suction pipe adapted for insertion into the container.

The invention will now be described in more detail below by means of an example of an embodiment and with reference to the schematic drawing, in which

Fig. 1 is a side view of a production line comprising an apparatus according to the invention,

Fig. 2 is a top view of the production line of Fig. 1,

Fig. 3 shows an enlarged segment of Fig. 1, Fig. 4 shows an enlarged segment of Fig. 3 comprising the apparatus according to the invention,

Fig. 5 is a view corresponding to that of Fig. 3, but at another point of time of a production process, and Fig. 6 shows an enlarged segment of Fig. 5 comprising the apparatus according to the invention.

Figs. 1 and 2 show a production line on which items, such as fish or fish fillets, are salted by the injection of brine and are laid down in layers into brine in a container for curing. The figures thus show a brine injection machine 1 having a first belt conveyor 3 with an upstream end 5, a brine injection station 7 and a control panel 9. It should be noted that the brine injection station 7 of Fig. 2 is shown transparently so that the items on the belt conveyor at the brine injection station are visible. Items 11 to be injected with brine are placed on the upstream end 5 of the belt conveyor, whereupon the belt conveyor passes the items through the brine injection station. The belt conveyor 3 is usually driven intermittently, the brine injection station 7 comprising a so-called needle beam (not shown) extending transversely to the belt conveyor and passing injection needles down into items under the needle beam to inject brine while the belt conveyor 3 is standing still. Brine injection machines of this type are known per se. After the brine injection station 7, the items leave the belt conveyor 3 at its downstream end 13.

A container carrier 15 for two containers 17 containing brine into which the items 11 are to be laid down is seen at the other end of the production line. The container carrier 15 is supported by wheels 19 and is turnable about a vertical axis 21 so that it is possible to switch the positions of the two containers 17 by rotation about the vertical axis. At such rotation, the corners of the containers 17 will describe the circle 23 shown in Fig. 2.

A brine control device 25 (not shown in Fig. 2) including a brine container 27, a suction pipe 29 with a level meter, a pump 31 and a control device 33 is located above the container carrier 15. A jack 34 is incorporated into the container carrier 15 and is able to tilt a container 17 carried by the container carrier 15, as shown in Figs. 5 and 6.

A transfer apparatus 35 for laying down the items 11 arriving from the brine injection machine into a container 17 in the container carrier 15 is arranged between the brine injection machine 1 and the container carrier 15.

As best seen in Fig. 4, the transfer apparatus 35 comprises two conveyor parts in the form of a movable conveyor 37 and a stationary conveyor 39. The two conveyors are mounted in a frame 41, the stationary conveyor 39 being mounted so as to be fixed, and the movable conveyor 37 being suspended so as to be horizontally displaceable forwards and backwards in its direction of length and transport 43.

In the embodiment shown, the two conveyors are independent belt conveyors. Accordingly, the movable conveyor 37 has an endless belt 45 extending from an upstream roller 47 through a first overlying stretch 49 to a downstream roller 51 and therefrom through an underlying stretch to a drive roller 53, from which the belt 45 returns to the upstream roller 47. Along the underlying stretch, the belt 45 is supported by intermediate rollers 55a, 55b and 55c. Along the overlying first stretch 49, the belt 45 is passed over an intermediate roller 57 at which the belt changes direction from being substantially horizontal to extending downwards. Along the underlying stretch, the belt 45 also changes direction at the passage of the intermediate roller 55a so that the belt 45 extends obliquely upwards from the downstream roller 51 to the intermediate roller 55a and substantially horizontally after the intermediate roller 55a. In this way, the downstream end 59 of the movable conveyor 37, i.e., the portion of the conveyor from the intermediate rollers 55a and 57 and comprising the downstream roller 51, extends obliquely downwards. This makes the lower stretch concave. At the downstream roller 51, the movable conveyor 37 of the embodiment shown is provided with a chute 61 extending in continuation of the first overlying stretch of the belt 45. The effect of the chute 61 and the movable conveyor 37 as a whole will be described in more detail below.

Like the movable conveyor 37, the stationary conveyor 39 is provided with an endless belt 65 extending from an upstream roller 67 through a second overlying stretch 69 to a downstream roller 71, and therefrom through an underlying stretch to a drive roller 73, from which the belt 65 returns to the upstream roller 67. Along the underlying stretch, the belt 65 is supported by intermediate rollers 75a, 75b and 75c. Along the overlying second stretch 69, the belt 65 is passed over an intermediate roller 77 at which the belt changes direction from being substantially horizontal to extending downwards. Along the underlying stretch, the belt 65 also changes direction at the passage of the intermediate roller 75a so that the belt 65 runs obliquely upwards from the downstream roller 71 to the intermediate roller 75a and substantially horizontally after the intermediate roller 75a. In this way, ^λ c of the stationary conveyor 39, i.e. the portion of the conveyor from the intermediate rollers 75a and 77 and comprising the downstream roller 71, extends obliquely downwards. Thereby, also the lower stretch of the stationary conveyor is concave. In the embodiment shown, the stationary conveyor 39 is not provided with a chute like the movable conveyor.

The transfer apparatus 35 is arranged so that the downstream end 13 of the brine injection machine 1 is located closely to the second overlying stretch 69 to deliver items thereon. For the purpose of control of the movements of the conveyors 37 and 39 of the transfer apparatus 35, a detector 81, e.g., a photo cell, registering the items transferred to the conveyor 39 from the brine injection machine 1 is arranged at the downstream end 13 of the brine injection machine 1. The control device 33 receives signals from the photo cell 81 and controls the speeds of the belts 45, 65 of the conveyors of the transfer apparatus 35 and the forward and backward movement of the movable conveyor 37. The production line functions as follows:

Initially, a container 17 with brine is arranged in the container carrier 15, e.g., by means of a forklift truck 82 as indicated at the right side of Fig. 1. While a container is in position for filling at the left side of the container carrier 15 as seen in Fig. 1, a container may be replaced at the right side of the container carrier. By rotation of the container carrier 15 about the vertical axis 21, any container 17 already filled with items 11 may be moved from the left to the right side of the container carrier 15 as seen in Fig. 1, while a new container without items is

, moved oppositely. Preferably, the new container is tilted by means of the jack 34 so that the container 17 is held in the position shown in

Figs. 5 and 6. The suction pipe 29 with a level meter is inserted into the new container, and any excess liquid or brine is sucked up and passed to the brine container 27 by means of the pump 31. By means of valves, not shown, the brine in the container 17 may be supplemented with brine from the brine container 27 if the level in the container 17 appears too low. The brine control device may be adapted to control the density of the brine in the container 17 so that it is kept within desired limit values.

Items, such as fish, to be salted are placed in a formation 83, corresponding to a layer intended to be laid down into brine in a container 17, on the upstream end 5 of the belt conveyor 3 of the brine injection machine 1. The belt conveyor passes the formation through the brine injection station 7, and as the formation 83 is passed forwards by the belt conveyor 3 and leaves the upstream end, another formation 83 is laid, a space being left between consecutive formations. The formations are placed manually and have a predetermined length in the direction of transport 43 corresponding to the length of the container 17.

While a formation 83 which has passed the brine injection station 7 is transferred from the downstream end 13 of the belt conveyor 3 to the second overlying stretch 69 associated with the stationary conveyor 39, the latter's belt 65 is conveyed in step with the belt conveyor 3, whereby the formation 83 is transferred substantially without mutual displacement of the items 11 from the belt conveyor 3 to the belt 65. While one formation 83 is being transferred from the belt conveyor 3 to the belt 65, the movable conveyor 37 is moved to the projected position shown in Figs. 5 and 6. When the detector 81 has registered that a full formation 83 has been transferred from the belt conveyor 3 to the belt 65, the belt is accelerated to a relatively high speed, and the belt 45 of the movable conveyor 37 is accelerated to the same relatively high speed. Thereby, the formation 83 is moved through the second stretch 69 and over the downstream end 79 of the stationary conveyor 39 to the first stretch 49 associated with the movable conveyor 37 where the formation 83 is moved on to the downstream end 59. As the front part of the formation 83 reaches the end of the movable conveyor 37, i.e., the chute 61, the movable conveyor 37 is moved backwards, i.e., a movement in the opposite direction to the direction of transport 43, at a speed equal to the relatively high speed at which the belts 45 and 65 are running. In this way, the movement of the formation 83 in the direction of transport 43 is stopped, and the movable conveyor is removed under the formation as the items 11 slide over the chute 61 and are laid down on the surface of the brine in the container 17, the movable conveyor 37 being moved to the position shown in Figs. 1, 3 and 4.

The density of the brine has been adjusted so that the items will only just float in the brine. The formation 83 will therefore remain lying in the surface of the brine until a new formation is subsequently placed on the surface as just described. The most recently laid formation will press previously laid formations down into the container 17, which will gradually fill up. In step with such filling of the container, brine is sucked up through the suction pipe 29 under the control of the control device 33 in response to signals from the level meter. Thereby, the level of the surface of brine in the container 17 is maintained. The quantity of brine so sucked up during filling is measured, and as this quantity corresponds to the volume of the quantity of items 11 filled into the container, control of the quantity of items 11 in the container 17 is thus achieved.

As the container 17 at the left side of the container carrier 15 is tilted by means of the jack 34, the surface 85 of the brine comes close to the rim 87 of the container 17 at its left side as seen in the Figures. Moreover, the concave design of the underside of the conveyor 37 with its lower stretch makes it possible to place the conveyor 37 with the chute 61 immediately above the level of the rim 87, the chute 61 being the lower point of the part of the conveyor 37 which is moved over the container 17. These two features ensure that the end of the chute 61 is close to the surface 85 during the transfer of items from the chute 61 to the surface 85, which contributes to ensuring that the items are laid on the surface 85 while maintaining the mutual position of the items 11 in the formation 83.