DEVICE FOR CONVEYING TINS FROM A PALLET ONTO A CONVEYOR BELT

Abstract: A device for taking up a layer (5) of magnetizable tins (6) positioned one beside the other, from a pallet (4) and for conveying these onto a conveyor belt (13), said device comprising a first conveyor belt (7) extending in substantially horizontal direction above a pallet. Above the lower part (10) of this first belt (7) at least two plate-shaped magnets (11,12) are provided. Means being present to pull the upper layer (5) of tins (6) against the lower part (10) of the conveyor belt (7) by means of said first magnet (11) whereafter these tins are brough below the second plate-shaped magnet (12) and from this onto the second conveyor belt (13). Said magnets (11,12) being either adjustable in height or being electro-magnets which can be energized in a controlled way.

Description: The invention relates to a device for taking up a layer of tins positioned one beside the other, from a pallet and for conveying these onto a conveyor belt, said device comprising a first conveyor belt extending in substantially horizontal direction above a pallet with layers of magnetizable tins stacked thereon, whereby above the lower part of this first conveyor belt at least two plate-shaped magnets are provided, a first one of which is having a size at least corresponding to the surface of the pallet, said magnets lying ad­ jacent each other in the direction of movement of said conveyor belt so that the first plate-shaped magnet may be positioned above the pallet with the magnetizable tins with the lower part of the conveyor belt between the magnet and the tins, means being present to pull the upper layer of tins against the lower part of the conveyor belt whereafter the conveyor belt is conveying this layer of tins up to below the second plate-shaped magnet, a second conveyor belt being positioned below the second plate-shaped magnet at such a level that the tins, carried by the second magnet, are at a slight distance above the second conveyor belt and are released by said second magnet to be deposited on said second conveyor belt to be removed by this. Such a device is known from DE-B-2,222,678. In case of this known device the plate-shaped magnets are permanent magnets and are fixedly positioned above the lower part of said first conveyor belt. Further the second plate-­ shaped magnet is applying an attracting force on the tins which is decreasing in the direction of movement of the tins, so that the tins will be released by said magnet. In view of the fact that there can be differences in the sizes and/or the weight of the conveyed tins, the one tin can be released by the magnet somewhat earlier than a preceding tin, so that the tins will not be deposited on the second conveyor belt in the same pattern as they were taken up from the pallet. Now the object of the invention is to remove this dis­ advantage. To that end a device according the invention is characterized in that the second plate-shaped magnet is also having a size corresponding to the surface of the pallet, said second magnet being executed such that the force by which the tins are pulled against the lower part of the first conveyor belt can be varied at will and all the tins of a layer which have arrived above the second conveyor belt can be released by the second magnet at one and the same point of time. According to the invention it is preferred that also the first plate-shaped magnet is executed such that the force by which the tins are pulled against the lower part of the first conveyor belt can be varied at will. In this way it is guaranteed that all tins of a layer can be pulled against the conveyor belt at the same moment. In view of this it is prevented that a tin which is not yet attracted by the magnet is hampering the movement of the other tins. In this way a particularly simple and reliable acting device is obtained making little noise as well. According to a first embodiment of the invention the plate-shaped magnets can be permanent magnets and can be displaceable substantially in vertical direction above the lower part of the first conveyor belt. It will be obvious that when the permanent magnets are positioned close above said part of the conveyor belt tins can be attracted while when afterwards the magnet is moved upwardly the tins will be checked by the conveyor belt so that they will get free from the magnet. According to an other embodiment it is also possible that the plate-shaped magnets are electro-magnets which may be energized in a controlled way. In this case the current to the magnets can be switched on and off so that the magnets may hold the tins or release them. In order to set down a number of tins on the second conveyor belt in a well controlled way, also if the distance between both conveyor belts is larger than the height of the tins, it may be provided that a plate-shaped magnet is mounted below the upper part of said second conveyor belt at a location substantially perpendicular below the second plate-shaped magnet of the first conveyor belt. According to a preferred embodiment of the invention it may be provided, that the first conveyor belt is continuously moving with a speed between l and 40 m/min. and that the moment at which a layer of tins is released by the second magnet is determined by a sensor, the speed of the second conveyor belt being at least equal to that of the first conveyor belt. It is, however, also possible that the first conveyor belt is moving discontinuously and is stopped by a sensor when a layer of tins has been brought above the second conveyor belt whereafter the tins are set down on the second con­ veyor belt. As, generally speaking, the second conveyor belt will occupy a fixed position it is preferred that the device comprises a support for a pallet which support is adjustable in height such that a pallet may be brought to that level at which the uppermost tins on the pallet are found closely to the lower part of the first conveyor belt. In order to make the device suitable for various types of tins it may be provided that the vertical distance between the first and the second conveyor belt is adjustable. Though in most cases the first conveyor belt will be in a substantially horizontal position it is also possible to vary this position over ± 20°. For controlling the device in particular use will be made of a relais or PLC controlling. The invention now will be elucidated by means of an example, a side view of which is shown in the drawing. The device shown in the drawing comprises some fixed support legs l, over which additional legs 2 may be moved carrying a support plate 3 on which a pallet 4 is present on which a number of layers 5 of tins 6 are stacked. The support plate 3 is movable upwards en downwards in vertical direction as indicated by the arrow P. This move­ ment e.g. can take place by telescoping the legs l and 2 in- and outwardly by hydraulical or mechanical means. An endless conveyor belt 7 runs over reversing rollers 8 of which at least one will be driven and over guide rollers 9. Above the lower part 10 of the conveyor belt two plate-­ shaped magnets 11 and 12 are positioned which are placed closely together. As stated already above the magnets 11 and 12 may be electro-magnets but they may be movable in vertical direction too, as indicated with the arrows R. If then they are far enough away from the lower part 10 of the conveyor belt 7 they will release the tins 6. When using the device the conveyor belt 7 will move in the direction of the arrow S and the magnets 11 will be energized or will be positioned so close above the part 10 of the conveyor belt 7 that the upper layer 5 of tins 6 will be attracted by the magnets 11 and will be taken along by the conveyor belt 7 untill the layer is positioned below the magnet 12, as indicated by 5a. By deenergizing the magnet 12, if this is an electro-­ magnet, or by moving upwardly the magnet 12 if this a permanent magnet, the layer 5a may be released from the magnet and it will be set down on the second conveyor belt 13 of which only a part is shown in the drawing and which is running over the reversing roller 14. Another magnet 15 still may be provided below the upper part 14a of the second conveyor belt 13 in order to pick up the tins in the correct position. Preferably the magnet 15 will be a permanent magnet because the tins will be released automatically from the magnet 15 on movement of the conveyor belt 13 in the direction of the arrow T. For controlling the device primary use can be made of a sensor 16 observing whether the support plate 3 has been moved upwardly to such an extent that the tins can be attracted by the magnet 11. The sensor 16 simultaneously can serve for controlling the height-adjusting of support plate 3. The sensor may be of the mechanical type but e.g. also can be formed by a light source with relating recorder. In order to observe whether the tins taken along by the conveyor belt 7 are in the position above the second conveyor belt 13, use can be made of a sensor 17 which then ascertains that the tins are put down on the second conveyor belt. Additionally a further sensor 18 may be present to observe whether a layer of tins 5 is displaced far enough towards the right, as seen in the drawing, to bring the support plate 3 upwards again in order to supply the subsequent layer of tins to the magnets 11. All these and further possibilities, however, will be obvious to an expert and also it does not require further elucidation either that many modifications may be made without leaving the inventive concept.

Claims: 1. A device for taking up a layer (5) of tins (6) positioned one beside the other, from a pallet (4) and for conveying these onto a conveyor belt (13), said device comprising a first conveyor belt (7) extending in substantially horizontal direction above a pallet (4) with layers (5) of magnetizable tins (6) stacked thereon, whereby above the lower part (10) of this first conveyor belt (7) at least two plate-shaped magnets (11,12) are provided, a first one (11) of which is having a size at least corresponding to the surface of the pallet (4), said magnets (11,12) lying adjacent each other in the direction of movement of said conveyor belt (7) so that the first plate-shaped magnet (11) may be positioned above the pallet (4) with the magnetizable tins (16) with the lower part (10) of the conveyor belt (7) between the magnet (11) and the tins (6) means being present to pull the upper layer (5) of tins (6) against the lower part (10) of the con­ veyor belt (7), whereafter the conveyor belt (7) is conveying this layer (5) of tins (6) up to below the second plate-shaped magnet (12), a second conveyor belt (13) being positioned below the second plate-­ shaped magnet (12) at such a level that the tins (6), carried by the second magnet (12), are at a slight distance above the second conveyor belt (13) and are released by said second magnet (12) to be deposited on said second conveyor belt (13) to be removed by this, characterized in that the second plate-shaped magnet (12) is also having a size corresponding to the surface of the pallet (4), said second magnet (12) being executed such that the force by which the tins (6) are pulled against the lower part (10) of the first conveyor belt (7) can be varied at will and all the tins (6) of a layer (5) which have arrived above the second conveyor belt (13) can be released by the second magnet (12) at one and the same point of time. 2. A device according to claim 1, characterized in that also the first plate-shaped magnet (11) is executed such that the force by which the tins (6) are pulled against the lower part (10) of the first conveyor belt (7) can be varied. 3. A device according to claim 2, characterized in that the plate-shaped magnets (11,12) can be permanent magnets and can be displaceable substantially in vertical direction above the lower part (10) of the first conveyor belt (7). 4. A device according to claim 2, characterized in that the plate-shaped magnets (11,12) are electro-magnets which may be energized in a controlled way. 5. A device according to one of the preceding claims, characterized in that a plate-shaped magnet (15) is mounted below the upper part (14a) of said second conveyor belt (13) at a location substantially perpendicular below the second plate-shaped magnet (12) of the first conveyor belt (7). 6. A device according to one the preceding claims, characterized in that the first conveyor belt (7) is continuously moving with a speed between 1 and 40 m/min and that the moment at which a lower (5) of tins (6) is released by the second magnet (12) is determined by a sensor (17), the speed of the second conveyor belt (13) being at least equal to that of the first conveyor belt (7). 7. A device according to one of the claims 1 - 5, characterized in that the first conveyor belt (7) is moving discontinous­ ly and is stopped by a sensor (17) when a layer (5) of tins (6) has been brought above the second conveyor belt (13) whereafter the tins (6) are set down on the second conveyor belt (13). 8. A device according to one of the preceding claims, characterized in that it comprises a support (1,2,3) for a pallet (4) which support (1,2,3) is adjustable in height such that a pallet (4) may be brought to that level at which the uppermost tins (6) on the pallet (4) are found closely to the lower part (10) of the first conveyor belt (7). 9. A device according to one of the preceding claims, characterized in that the vertical distance between the first (7) and the second conveyor belt (13) is adjustable. 10. A device according to one of the preceding claims, characterized in that the position of the first conveyor belt (7) can be varied over ± 20° from the horizontal position. 11. A device according to one of the preceding claims, characterized in that for controlling the device use is made of a relais or PLC controlling.

Inventors: VAN UITERT, JOHANNES HENDRIKUS
Applicants: SPECIAAL-MACHINEFABRIEK J.H. VAN UITERT B.V.
Application year: 1986
Main classification: B65G57
IPC codes: B65G57, B65G59