The invention concerns a magazine arrangement, comprising a number of open, lengthy cassettes for accommodating each a stack of flat objects, such as can lids, and also an apparatus, which has a first path for lengthways carrying the cassettes separately past a charge and/or discharge unit for charging or discharging the cassettes, a second path in front of the first one to accumulate a wanted number of cassettes and to carry these cassettes one at a time crosswise in front of the charge and/or discharge unit in the first path, and a third path, after the charge and/or discharge unit, for carrying one at a time the cassettes which have left the charge and/or discharge unit, crosswise .along the first path and accumulate a wanted number of these cassettes after this path,

Norwegian patent No. 32715 discloses an apparatus for automatically charging lengthy cassettes with can lids. This apparatus has a stand with a frame being vertically displaceable up and down in the stand. In this frame there is placed a horizontally displaceable first cassette, with a second cassette being divided in partitions with the same width as a can lid. The lids are manufactured in a press and are successively guided from this press out into one of the said partitions whereby the two cassettes at the same time are being lowered stepwise until this partition is charged with lids. Then the cassettes are elevated while they at the same time are being horizontally displaced in the frame at a distance equal to the width of a lid, whereby a new partition gets into the charging position. The process is repeated until all of the partitions in a cassette have been charged, whereafter the charged cassette can be removed from the right side. A new, empty cassette has in the meantime been placed in the left side of the frame guidance so that the apparatus will function without stopping.

The manipulation with these double cassettes is very difficult and requires utmost attention and almost constant supervision from the operating personnel. The first cassette must be placed with accuracy in the frame guidance in order to make the apparatus function and this operation must take place at the same time as the frame is moving. Another problem is the fact that the cassettes are open in the front and consequently there is a risk for the vertically stocked lids to fall out.

The mechanism in question is furthermore expensive and complicated and is not suitable for following the high production speed existing in modern production plants for manufacturing can lids. The apparatus can, by the way, only be used for charging the cassettes with lids, and the patent specification has no instructions with regard to how they are discharged.

WO patent specification No. 89/10319 discloses a similar apparatus, which however can be used for as well charging as discharging lengthy cassettes for e.g. can lids. Also in this case the cassettes are carried upright, horizontally and vertically through the apparatus. During the vertical passage the cassettes are transported separately by means of two endless belts guiding the cassette in question by engaging its sides. Beside this, the patent specification is practically silent as to how the cassettes then are guided through the plant without tipping over and without the lids falling out of the open front.

If the apparatus is supposed to be able to function with reasonable reliability of operation it must, however, has a sort of a guide for supporting the upright standing cassettes, and thereby the same problems of operation will arise as disclosed from the above-mentioned Norwegian patent. Even if the cassettes are secured from tipping over in this way, the lids will continue to be inclined to fall out of the open

front of the cassettes. This tendency is especially a great inconvenience for the personnel having to place the charged cassettes in the guide of the apparatus or to discharge the charged cassettes from this guide, and who during this operation very carefully must see to that all of the lids are correctly in position up against the vertically placed bottom and that no lids fall out of the open front of the cassette.

The object of the invention is to provide a magazine arrangement of the type mentioned in the opening paragraph which has a simple and reliable construction, is handy to operate, requires minimal working effort and supervision of the operating personnel, and which moreover can function with very high rates of production.

This is, according to the invention, achieved in that all three paths in the apparatus are formed in such a way that each of the cassettes during the stay and passage of a path is upright standing with a backwards turned inclination in proportion to a vertical plane. Thereby the cassettes are secured from tipping over as they are supported of the path of the apparatus and are holded in abutment against these by the gravitation. The latter also provides for the fact that all of the lids appropriately will abut on the bottom of the cassettes and that none of these will fall out of the open front of the cassettes.

However, if the inclination is exceeding a certain limit there may be a risk that the stack of lids skids, and if it, on the other hand, is too little, there may be a risk to the fact that the lids will not for certain come into position against the bottoms of the cassettes, and some of them might even fall out. The correct stacking and position of the lids in a cassette is best to be obtained if the angle, which each of the cassettes inclines in proportion to a vertical plane is

between 5° and 60°, preferably between 10° and 40°, and especially between 20° and 30°.

When the paths of the apparatus are builted op in a stand and are situated in inclined planes with the same inclination, since the second and third path extends horizontally, each within its own plane, while the first path extends perpen¬ dicular to the two other paths, it is furthermore immediately easy for the operating personnel to place cassettes on the horizontal paths and remove them again.

The transportation of the cassettes on the horizontal paths can furthermore advantageously take place by means of smooth belt conveyers allowing the cassettes a relative sliding in relation to the belt conveyers which thereby partly can carry the cassettes to and fro the first path, and partly can allow an accumulation of the cassettes on the horizontal paths.

Also the transportation through the first path can advantageously take place by means of one or more belt conveyers, which in that case must not be smooth, but on the contrary be able to act on a cassette placed on the first path, with an adequate high frictional force in order to overcome the result of the gravitation force.

The invention will be explained more fully by the following description of an embodiment, which just serves as an example, with reference to the only figure of the drawing showing a magazine arrangement according to the invention, generally designated by the reference numeral 1.

This arrangement comprises a number of lengthy, open cassettes 2, and an apparatus 3 with a stand 4. The cassettes 2 serves the purpose each to accommodate a stack of flat objects, which in the case shown are supposed to be lids 5 for cans.

A charge and/or discharge unit 6 of the type disclosed as an example in the above-mentioned WO patent specification No. 89/10319 serves the purpose of charging or discharging a cassette 2. For this purpose the apparatus 3 has a first path 7 for lengthways carrying the cassette past the charge and/or discharge unit.

In this path there is in this case placed two belt conveyers 8 with narrow, for instance, wedge shaped belts 9 being squeezed into feed grooves 10 on each side of the cassette. By means of these belt conveyers 8 the cassette 2 can successively be carried past the charge and/or discharge unit currently with the cassette being charged or discharged. A lifting arm 11 on a lifting mechanism 12 is furthermore serving the purpose of lifting the cassette 2 up to engagement with the belt conveyers 8 or lower it so that the belt conveyers can loosen their engagement without free falling of the cassette.

In stead of the above-mentioned two belt conveyers 8 one single underlying belt conveyer, not shown, can be used, having an endless belt with such a coefficient of friction that the cassettes will not slide down the belt acted on by the gravitation. This belt can, for instance, be supplied with traversing driving ribs being able to accommodate the weight composant of the cassettes in the longitudinal direction, but allowing the cassettes to be crosswise displaced on the belt. In this case there will be no need for the lifting mechanism 12 since said underlying belt conveyer is able to support the cassettes in the first path in the full length of this path.

Beside the first path 7 the apparatus has a second path 13 and a third path 14 both of which are extending in horizontal direction, respectively, to and fro the first path 7 in an angle of 90°.

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In the second path a belt conveyer 15 is placed having two endless belts 16 and 17 of a smooth material, such as polyester. The belt runs around rolls 18 driven by a motor 19.

In the third path 14 there in the same way is placed a belt conveyer 20 with two endless belts 21 and 22 from a smooth material such as polyester. The belts are running around rolls 23 driven by a motor 24.

Below the second path 13 there is furthermore in this case a ledge 26 with a smooth surface or a belt conveyer, not shown, and below the third path 14 there is a ledge 27 with a smooth surface or a belt conveyer, not shown.

The stand 3 with the three paths 7, 23 and 14 is situated inclined to the rear on the base frame 4 in an angle of inclination v in proportion to a vertical plane. The paths 7 and 14 are situated in principle in the same level, while the path 13 is somewhat displaced with a distance of minimum the same size as the height of the cross section of a cassette in proportion to this plane. A pusher 29 serves the purpose of pushing a cassette from the second path 13 up into the level of the other two paths.

The apparatus is controlled by means of a switchboard 28 and functions in the following way, under the presumption that the apparatus is used for charging cassettes which are carried through the apparatus in direction of the arrows, and also under the presumption that an operator has put a number of empty cassettes on the ledge 26 and the belt conveyer 15 of the second path 13.

According to requirement this belt conveyer can in this connection be dimensioned with such a great length that it can accommodate adequately the cassettes in such a way that the operator only with predetermined time intervals will have to

place new empty cassettes on the belt conveyer 15. The rest of the time the apparatus can operate on its own without service and supervision, and the manual work being necessary is furthermore limited to a minimum since the former difficult work in carrying cassettes in and out of the guides of the conventional apparatus completely has been eliminated. The cassettes merely have to be placed on a belt conveyer, inclined to the rear, having a lower, smooth ledge or a lower, not shown, belt conveyer for supporting the cassettes, which thereby automatically are placed in correct positions by the belt conveyer 15, and the same conditions take effect in the case of the third path 14. The apparatus according to the invention is consequently very labour-saving.

As it can be seen, there is now a stock of empty cassettes on the belt conveyer 15. The cassettes are by the belt conveyer carried in direction of the arrows towards the first path 7 where the first cassette in the row will be brought to stop by a stop 30. The succeeding cassettes will then be packed in front of the first one since all of the cassettes in this process will slide on the belts 16 and 17 which thereby will act as an accumulator for the cassettes.

At the same time a cassette is on its way down through the first path 7 in the direction of the arrow. This cassette is transported stepwise downwards by the belt conveyers 8, while it successively is charged with lids by means of a charge and/or discharge unit 6. When the cassette is released from the belt conveyers 8, it is further lowered downwards until it itself is engaged by the arm 11 of the lifting mechanism, until the lower end of the cassette now charged has been put to rest on to the ledge 27.

When the cassette, which is coming down through the first path 7, has come so far that its upper edge is at the same level as the topside of the ledge 26, the front cassette on the belt

conveyer 15 of the second path 13 is by the pusher 29 shot up to the level of the first path 7 and is now standing on the underlying cassette in the path 7 for subsequently to follow this cassette downwards until it itself will be engaged by the belt conveyers 8 and starts to be charged with lids by means of the charge and/or discharge unit 6.

The cassettes which have been charged with lids and lowered on to the ledge 28 of the third path 14, is now by the belt conveyer 20 of the third path 14 carried away from the first path 7 in the direction of the arrows, so that there will be room for lowering another filled cassette down on to the ledge 27.

As is the case for the second path 13 there can be accumulated so many cassettes on the third path 14, that the operator only periodically needs to be present to remove the charged cassettes. This operation can very easily take place since the charged cassettes only have to be lifted off the belt, and due to the inclination there is no risk that the lids will fall out during this operation.

The magazine arrangement has above been described under the condition that it is used for charging the cassettes with lids. If it, however, is being used for discharging of cassettes already charged, the process will take place in the reverse order.

The charged cassettes are then placed on the belt conveyer 20 of the lower horizontally extending path which will accumulate a suitable number of charged cassettes and take the first one in the row in front of the charge and/or discharge unit 6 in the first path 7. The lifting arm 11 of the lifting mechanism 12 will elevate the charged cassette up into engagement with the belt conveyers 8 taking the cassette further on past the

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discharge unit 6, which then successively will empty the cassette for lids.

When this cassette is emptied and its lower end-gable has come into level with the ledge 26 of the upper horizontally extending path the empty cassette will now be lowered by the pusher 29 down into level with the upper path's belt conveyer 15, which then will take this cassette along the first path in order to make room for another empty cassette. The belt conveyer 15 is at the same time serving the purpose of accumulating a suitable number of empty cassettes.

As it can be seen, the magazine arrangement is extremely easy to operate, because the apparatus has not, as is the case with conventional apparatuses of this kind, guides to prevent the upright standing cassettes to tip over. The guides have been superfluous by the inclination of the ^' stand whereby the gravitation is used to hold the cassettes safely in position by abutment against the diagonally lying belt conveyers 13, 14 and the ledges 26, 27.

Another advantage obtained by the inclination of the stand is the fact that neither when the cassettes are handled manually nor when they are transported through the paths of the apparatus, there is no risk that the lids will fall out. On the contrary, the lids themselves will seek down towards the bottom of the cassette acted on by the gravitation.

It is however, in this connection, a.o. important that the right angle of inclination v is chosen. If this angle is too big the stack of lids in a cassette will be inclined to skid and if it is too small there is a risk that the lids will fall out.

In order to safely eliminate this risks the inclination angle v should be between 50° and 60°, preferably between 10° and

40°, and especially between 20° and 30°. At these inclination angles each lid will automatically by the gravitation be forced into a position where its plane is perpendicular to the longitude direction of the cassette and its lower edge is lying up against the bottom of the cassette.

It is to be noticed that in stead of the belt conveyers 15 and 16 in the paths 13 and 14 other kinds of feed mechanisms can be used, e.g. pushers pushing the cassettes along a smooth underlying. The important fact is that this underlying inclines the angle v in relation to a vertical plane.

In the figure the two horizontal paths 13 and 14 of the apparatus are extending perpendicularly out to the left side in proportion to the first path. This configuration is, however, only an example and the two paths can, if required, both extend out to the right side and to each of the sides in relation to the first path so that the apparatus adequately can be configured for a certain purpose of use.

Furthermore the figure shows only the apparatus in one embodiment as an example, where it can be used for either charging or discharging of cassettes. However, within the scope of the invention a not shown embodiment can be imagined, where these two functions are combined in one single combined apparatus having only two horizontally extending paths 13 and 14, but a first path at each of the ends of these two horizontal paths, so that in this embodiment there are now two paths with opposite transportation directions, one of the paths being equipped with a charge unit and the other with a discharge unit.

This combined apparatus is operating in such a way that a number of cassettes continue to circulate in a closed circuit and consequently it is suitable as a buffer between e.g.

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eccentric presses making successive operations on stackable objects.

E.g. objects from one eccentric press can be stacked in cassettes in the path being equipped with the charge unit, while the succeeding eccentric press is being supplied with these objects for further treatment from cassettes in the path being equipped with the discharge unit. The two presses therefore do not have to operate in time, but can to a great extend operate independently of each other, due to the fact that in a space of time, depending of the number of circulating cassettes, there will be a sufficient number of cassettes for either charging or discharging.

By means of this arrangement the advantage is obtained that two eccentric presses or similar machines can co-operate at the same time even if their operations do not run synchronously. Furthermore a total suspension of operations can be avoided, e.g. in a line of production with several machines, even if one or more of these periodically may fall out due to working failure or when worn out or broken tools are to be replaced.

Furthermore the magazine arrangement has been described above under the condition that it is used for can lids. It is obvious for a person skilled in the art that it just as well can be used for many other objects which reasonably can be stacked.