WO1981002802A1

WO1981002802A1 - Compressor for packaging

Info

Publication number: WO1981002802A1
Application number: PCT/SE1981/000087
Authority: WO
Inventors: A Andersson; G Haegg
Original assignee: A Andersson; G Haegg
Priority date: 1980-03-14
Filing date: 1981-03-16
Publication date: 1981-10-01
Also published as: EP0054030A1; SE420135B; NO813851L

Abstract

A compressor for packaging, particularly for tins (9) of sheet metal having a generated surface, comprising a position (25) for the tin (9) with an insertion opening for the uncompressed tin, a discharged opening (30) for the compressed tin and two walls (29) which are opposite one another and which are adapted to be displaced, by a power device, so that the spacing between the walls corresponds to the intended compression dimensions for the tin the generated surface assuming a bellows-like shape after the compression. The discharge opening (30) is adapted to allow through a compressed tin but not an uncompressed one and is so situated in relation to the final position of the walls (29) that the tin, in its compressed state, tends to fall out through the discharge opening whereas it receives support before the compression.

Description

Title:

Compressor for packaging

Technical field:

The present invention relates to a compressor for packaging, preferably tins of the return type.

As a result of the fact that the interest in reusing material has increased, the return of packaging has been proposed. The interest has been primarily directed towards tins of aluminium, for example, for drinks, since aluminium is well suited for remelting while at the same time considerable savings in energy can be made,which is of current interest, by replacing newly produced aluminium by material produced from scrap. In addition, for environmental reasons it is desirable to collect aluminium tins because these have a very long disintegration time in nature. In order to stimulate the return flow, it has been proposed that the packaging should be subject to a deposit and on return to the point of sale where the goods in question are sold, the deposit should be paid back. Manual handling of the return packaging at the points of sale and paying out of the amount of the deposit must generally be out of the question for reasons of rationalisation. There must therefore be an increasing need for automatic return machines, particularly for aluminium tins. In order that the accumulated packaging may not take up too much room during storage and transport, however, it is desirable that a machine for compressing the packaging should be available at the receiving point and such a compressor may appropriately be combined with an automatic machine for receiving, packaging and paying out deposits.

Background art:

From the US patent specifications 3.412.83'7, Myers, 3,792.765, Arp and 3.207.087, Tanaka, machines are known which receive and compress sheet-metal packagings and pay out a deposit. These machines are considerably complicated with a large number of conveyor members.

The technical problem: There are many requirements for a machine of this type such as simplicity in operation, operational reliability even if non-intended articles are introduced, distinguishing between articles which are entitled to a deposit and those which are not entitled to a deposit and a rapid method of working. These requirements should be met with such a low machine cost that its acquisition is justified within the intended field ofapplication and' the energy consumption should also be limited as much as possible. This involves demands on the design of the machine so that said requirements can be met with simple and reliable means.

The solution:

The solution implies that only the force of gravity is primarily used for transport of the packaging inside the compressor, which provides a simple construction. The members for compressing are so constructed that the necessary forces remain low, which has an advantageous effect on the design.

Advantages: Through the invention, a compressor is obtained which is simple in construction and can be manufactured at a low cost while at the same time it is automatic and can serve anyone without the need for previous knowledge and which, at the same time, is very insensitive to errors and misuse, such as charging with packaging of a non-intended type. Brief description of drawings:

In the accompanying drawings, one form of embodiment of the invention is shown, this being described below with reference to the drawings. Figure 1 shows a front view of the device according to the invention; Figure 2 shows the interior of the device in a section substantially on the line II-II in Figure 1; Figure 3 shows the interior of the device in a frontal section substantially on the line III-III in Figure 2; Figure 4 shows, in perspective, a part of the device; Figures 5 smd 6 show diagrammatically two alternative embodiments of a detail; and Figure 7 shows a block diagram of the control functions of the device.

Best mode of carrying out the invention:

According to Figure 1, the device has a parallelepiped casing 1 with an upper portion 2 and a lower portion 3. The upper portion 2 accommodates the machine components of the device for its automatic operation while the lower portion 3 accommodates the storage space for returned packages received and separated articles received of a non-acceptable nature. The front of the upper portion comprises an insertion opening 4 which is surrounded by arrows 5 which can be illuminated, a control knob 12, an instruction panel 6, a so-called display with information which can be illuminated, a calculating panel 7 and a payment opening 8 for coins or the deposit receipt. The insertion opening 4 is so large that the intended packaging, in Figure 1 the end of a round tin 9 is shown, can easily be inserted by hand. The back of the casing 1 is adapted to be able to be opened to take out the returned packaging and said objects and for access to the mechanical equipment of the device.

Figure 2 shows the mechanical equipment situated inside the upper portion 2 of the casing and at the same time the upper portion of the container situated in the lower portion 3 for returned packaging. In the form of embodiment shown, the latter consists of a sack 10 which can be fixed in a holder device 11 to be removed when it is full and replaced by an empty sack. At the side of the sack 10, in the lower portion 3 of the casing there is a smaller container (on the right in Figure 3) for inserted articles which are not accepted by the device. This container may be considerably smaller than the container for returned packaging and may consist, for example, of a cardboard box which is installed in the casing alongside the sack 10.

The insertion opening 4 is shown in Figures 2 and 3 and it is formed in a short inclined tube 13 which is surrounded at the outside by a first annular capacitive sensor 14. Beyond this sensor there is situated a sliding shutter 22 which can be controlled between a closed and an open position (shown in Figure 1) by means of a power cylinder 23. Further in on the tube there is provided a further inductive sensor 15. This is at a certain distance from a third sensor 16 which is on a cover 17 which can be lowered opposite the inner end of the tube 13 by means of a power cylinder 18. Between the two sensors 15 and 16 there is a further sensor 19. The spacing between the sensors 15 and 16 is determined by the minimum length of tins 9 which it is desired to receive for paying out a deposit. According to the present standard for aluminium tins there are two lengths 120 mm and 155 mm with a diameter of about 60 mm. If it is desired that the device should accept both the shor er and the longer tin, the sensors 15 and 16 should thus be 120 mm apart. The sensor 16 is also adapted to sense the diameter of the tin. The sensor 19 between the rensors 15 and 16 is also of the inductive type and is adapted to sense the material of the tin 9. Aluminium actually has its own srecial inductive characteristics while other metals, for example steel, have other characteristics, and these differences can be recorded by the sensor 19. The tube 13 and the cover 17 should obviously be of a material which does not disturb the operation of the sensors. Connected to the inner, lower and open end of the tube 13 is a curved tube 20 which is terminated by a lower, open funnel-shaped end 21. The cover 17 is situated in the upper portion of this tube. Under the end portion 21, that is to say the lower mouth of the tube 20 there is a compressing device 24 with a chamber 25. This is formed by an end wall 26, side walls 27, 28 which form a V-shaped bottom, and a pressure plate 29. The side wall 27 does not extend entirely up to the end wall 26 but comprises an opening 30 which is about 45 mm from the end wall 26 with the said tin dimensions. The pressure plate 29 is fixed to a piston τod 31 of a power cylinder 32. The chamber 25 is adapted in position so that a tin falling down through the mouth of the end portion 21 lies with its side against the V-shaped bottom. It may be advisable to incline the chamber. In the figures, however, it is shown in a horizontal position.

The compressing device 24 is shown in more detail in Figure 4. The end wall 26 has been partly cut away for the sake of clarity. The side wall 27 with the opening 30 is fixed to the end wall 26 and to a second end wall 33 which also forms an attachment for the power cylinder 32 and which comprises a slot 34 for the passage of the piston rod 31 . The pressure plate 29 can be anved backwards and forwards by means of the power cylinder 32 between the end walls 33 and 26. The Figure also shows that the side wall 28 is pivotally suspended, by means of bearing journals 35 in the end walls 26 and 33 so that it can be swung between the closed position shown in Figures 3 and 4 in which the upwardly open cham ber 25 is formed with its V-shaped bottom and a swung out position in which the chamber is also open at the bottom. The downwardly directed opening is so large that a tin of the intended diameter placed in the chambe can fall out in an oblique downwardly directed movement as a result of the inclination of the side wall 27. The swinging of the side wall 28 between its two positions can be effected by means of a further power cylinder 35, the piston rod 37 of which is connected to the side wall 28.

Figure 4 also shows that the pressure plate 29, which is triangular so as to fit into the chamber 25 when the side wall 28 is closed, is provided with a cam 38 projecting into the chamber 25. This is also shown in Figure 5 where the pressure plate 29 with its cam 38 is shown close to the end wall 26 with a tin 9 shown in the compressed state. An alternative embodiment is shown in Figure 6 where the end wall 26 is also provided with a cam device, namely two cams 39 at each side of the cam 29. Here, too, the tin 9 is shown compressed. Figures 5 and 6 also show how the pressure plate 29 and the end wall 26 can be provided with grooves 40 which are intended to facilitate the escape of air and liquid during the compressing operation. For the operation of the cylinders 18, 23, 32 and 36 there is a compressor unit which contains a compressor and a pressure tank te store air under a certain pressure The tank is connected to the cylinders via valves which are net shown. The valves, which may appropriately be magnetically operated valves are controlled from a control unit to which the sensors 14, 15, 16 and 29 are connected The control unit is also connected to the arrows 5 to light them up and extinguish them, to the panel 6, to the calculating panel 7 and to a discharge device connect ed to the pay-out opening 8. The discharge device may be adapted to issue coins corresponding to the deposit received or a redemption ticket. If coins are issued, the device must, of course, be provided with a cash container and if a redemption ticket is used , there must be some form of printing mechanism. This equipment and control members such as magnetically operated valves and electronic devices for picking up the recording values from the sensors and control devices for the various panels can be prepared in detail by the expert on the basis of standard equipment and therefore do not need to be described in detail . How the device is organized is clear from the following block diagram and the description of its operation.

In the block diagram (Figure 7), the sensor 14 is found again which is connected, via a flip-flop 41 to an electronic unit 42 which gives a position of readiness to the three sensors 15, 16 and 19 which are connected in series with one another. and which are shown as a series of flip-flops 43 with two coupling positions. Also shown in the Figure are the compressed-air cylinders 18 and 23 for the covers 17, 22 and 32 and, 36 for the compressing device 24. In addition, part of the panel 6 is shown, the calculating panel 7, the control knob 12 and the pay-out unit which is designated by the pay-out opening 8. In addition a delay relay 45 is shown and a sensor 48 which is below the opening 30 in the chamber 25 and which is adapted to detect the passage of a compressed tin out through the opening 30.

45 designates a pressure sensor on the power cylinder 32. It is adapted to change over a unit, which is shown as a flip-flop 47, between a position in which the calculating panel 7 can be acted upon by the sensor 48 when the piston in the power cylinder 32 has completed its stroke and the pressure plate 29 has reached its position closest to the end wall 26, and a position in which the power cylinder 36 and the illuminating panel 6 are acted upon which occurs if the pressure in the power cylinder 32 exceeds a certain value. Furthermore, the device is provided with conventional auxiliary equipment such as limit switches so that the intended reciprocating movement of the pistons of the power cylinders can be obtained.

At rest, the mechanism assumes the position shown in the Figures.. If a tin 9 is now inserted, in the position shown in chain line in Figure 1, it slides down towards the cover 17. When the hand is inserted through the opening 4, the sensor 14 is actuated round the insert ion opening. The flip-flop 41 then changes over from the position shown in Figure 7 to its other position and so brings the unit 42 into the position of readiness. When the hand is withdrawn again, the actuation of the sensor 14 ceases and the flip-flop 41 changes position which actuates the unit 42 so that the sensors 15, 16 and 19 are coupled in. As a result of the fact that the tin is aligned in position by the cover 17, it has its ends close to the sensors 15, 16 and over the sensor 19. If the tin 9 has the correct dimensions and the correct material to be accepted as a returned packaging, the flip-flops 43 of the sensors assume the "correct" position which is the opposite to that shown in Figure 6. A puls e then passes through the flip-flops, which are now connected in series, to the magnetically operated valves, which control the cylinders 21 and 18 and their pistons execute a stroke so. that the covers 22, 17 change posit ion. As a result of the fact that the tube 13 is inclined, the tin 9 slides down along the tube and is not hindered by the cover 17 which is now open. The cover 21, on the other hand, closes the mouth of the tube 13 and prevents the insertion of a fresh tin. The tin slides further and out through the mouth of the end portion 21 and down into the chamber 25. The covers 17, 22 can now change position to the initial state and a new tin can be inserted. In conjunction with the activation of the cylinders 21, 18, the compressing cylinder 32 is also activated but through the delay relay 45 after a time which is measured so that the tin is atre to have arrived in the chamber 25. On activation of the cylinder, the pressure plate 29 is pressed towards the end plate 26 and the tin is compressed lengthwise (like a bellows). When the pressure plate 29 has reached its end position which is situated at a distance of somewhat less than 40 mm from the end plate 26 with the said tin dimensions, the plate returns to its initial position. Thus the now shortened tin loses its support and falls down through the opening 30 into the sack 10. As soon as the plate 29 bas returned to its initial position, the de vice is ready for a new cycle so that the covers can again change position when the correct values are present from the sensors.

During the compression of the tin, liquid can run out of it and liquid can also run out already in the tube 20. This liquid is collected on the V-shaped bottom and runs down into the sack 10 from this. The air which is pressed out of the tin can escape through the grooves 40 in the plates 26 and 29.

If one of the sensors 15, 16 or 19 should record a false value, that is to say if one of the flip-flops 43. in Figure 6 (seen diagrammatically) should remain in the position shown, no pulse reaches the cylinders 21, 17 by the path previously described. All the sensors must actually indicate the "correct" value for the course of events described to be obtained. Thus the cover 17 remains in the closed position and at the same time a pulse gees out to the panel 6 so that an indication is obtained that the object inserted is not accepted. It must therefore be taken out before the device can be jused again. The said conditions occur when some object other than a tin of the prescribed dimensions and/or of the prescribed material is inserted in the tube 13. With a tin which is too short, the two sensors 15 and 16 are not actuated and with a different material, the sensor 19 is not actuated. The said sensors and covers 22, 17 thus constitute a sorting device which prevents non-acceptable objects from being conveyed into the compressor. Nevertheless, as is clear from the preceding description, a further sorting device is provided in connection with the compressing device 24. There may actually be objects which are not indicated as unacceptable by the sensors, for example filled, unopened tins of the correct sort in themselves or aluminium tins with a considerably higher compression resistance than the prescribed packaging. This sorting device operates in the following manner : With a normal tin, a certain maximum resistance occurs on advance of the pressure plate 29, to which there corr esponds a certain maximum pressure in the power cylinder 32. If this pressure is not exceeded according to the indication in the pressure indicator 46, a signal can be given from the sensor 48 for the addition of a deposit amount in the calculating device which is represented by the calculating panel 7. This occurs when the compressed tin falls out through the opening 30 and past the sensor 48, which happens when the pressure plate

29 begins to return and the pressure against the compressed tin is reduced. On the other hand, if the maximum predetermined pressure in the cylinder 32 is exceeded, the piston stops and the exceeding of the pressure is indicated by the indicator 46. This leads to the flip-flop 43 giving a signal to the power cylinder 36 to pull in its piston rod whereupon the side wall 28 swings up and the object in the chamber 25 then rolls along the wall 27 in a laterally directed - downwardly directed movement and arrives outside the sack 10 in the special collecting space for unaccepted objects. In this case, the object does not pass the sensor 48 and so no signal goes out to the calculating unit. After the removal of the object from the chamber 25, the pressure plate 29 returns to its initial position and the side wall 28 is closed, after which the compressor is ready to receive a fresh tin.

Furthermore the significance of the projections 38 and 39 will be indicated with reference to Figures 5, 6. It has been found that considerable power is consumed during the compression of a tin in its longitudinal direction so that it may be pressed together like a bellows. Nevertheless, compression in this direction is preferable to compression in the transverse direction since the final result is a round, very well compressed piece of scrap which is easy to handle in bulk as distinct from the elongated, often bent pieces. which are obtained with transverse compression. In connection with the invention, it has been found that the necessary power can be reduced very considerably if the pressure plate is provided with the projections described. When these are pressed into the bottom or cover of the tin, a bending occurs which acts on the sides so that these no longer stand in the pressing direction, as a result of which the bellows formation is consider- ably facilitated. The effect can be further increased if, as indicated in Figure 6, the end wall 26 is also provided with projections. In order that the material may be as flat as possible, these projections 39 are offset in relation to the projection 38 on the pressure plate. Other arrangements of projections are also conceivable as is the replacement of en accentuated projection by a curved surface. What is important is that an initial bending of the sides of the tin is obtained, so that the bellows formation is facilitated. For each correct tin which is fed in, a pulse goes to the calculating unit and the panel 7 shows how many tins have been fed in in succession. For each complete infeed, an instruction "Press button for payment when all tins have been inserted" or the like is shown on the panel 6. When the device is ready to receive a fresh tin, the arrows 5 are illuminated. If several tins do not have to be fed in, the customer presses the button 12 in accordance with the request and payment takes place in accordance with the value received, through the payment opening 8, either in the form of coin or in the form of a ticket. In connection with this, the calculating unit is set to zero and the device is ready to receive a. fresh series of tins.

If a different object is inserted, a notice "Not accepted, deposit will not be paid out" or the like, lights up on the panel 6. The calculating unit is obviously not activated.

The device may appropriately be provided with an alarm to indicate when the sack 10 is full so that staff can change it. The device may appropriately be adapted so that the change of sacks and containers for foreign objects can be synchronized as can the replenishment of coin if this is paid out. As a result of the fact that compressed-air operation is used, a very rapid method of working can be obtained. The energy stored by the compressor can be extracted instantaneously with high effect values from the compressed-air tank, which is charged during the intermediate periods.

Certain variants and alternatives are conceivable within the scope of the invention. Thus the device can be adapted in its dimensions for other returned objects than tins of the said dimensions. It is also possible to replace the said capacitive or inductive sensors with other sensing members, and photodetectors may be used for example.

Claims

Patent Claims:

1. A compressor for packaging, particularly for tins (9) of sheet inetal having a generated surface and preferably also a bottom and cover at their ends, which compressor comprises at least one insertion point (4) for tins, a compressing device (24) situated beyond the insertion point and comprising a position (25) for the tin (9) or a plurality of tins with an insertion opening for the uncompressed tin situated above the position and a discharge opening (30) for the compressed tin or tins situated below in the position, two walls (26, 29) which are opposite one another and which are adapted to be displaced between a first position in which they are at such a distance apart that the prescribed tin, in the uncompressed state, has room between the walls and a second position in which the spacing between the walls corresponds to the prescribed compressed dimensions for the tin, and a power device (32) which is adapted to displace the walls between their two mutual positions and during displacement from the first to the second position, developing such a force that the prescribed tin is exposed to compression, the position (25) being adapted to receive the tin or tins with the generated surface extending between said walls (26, 29) so that during the compression the generated surface assumes a bellows-like shape, characterised in that the discharge opening (30) from the position (25) which is situated in a bottom portion thereof, is adapted to allow through a compressed tin but not an uncompressed one and so situated in relation to the end position of the walls (26, 29) in the second position that the tin (9) or tins tend, in their compressed state, to fall out through the discharge opening while before the compression they receive such support from the parts of the bottom portion outside the discharge opening (30) that they remain in the position.

2. A compressor as claimed in Claim 1, characterised in that said walls (26, 29) comprise at least one groove shaped recess (40) adapted to carry away air and possibly liquid during the compression.

3. A compressor as claimed in Claim 1, characterised in that at least one of said walls (26, 29) comprises a projection (38, 39) which is adapted to press in the bottom and/or cover of the tin (9) to such an extent that a bending of the cylindrical wall is obtained and the intended bellows formation is facilitated.

4. A compressor as claimed in Claim 3, characterised in that said projection has the form of a centrally situated cam (38) on the one end wall (29) and at least two cams (39) situated at the sides of the position for this cam (38), on the other end wall (26).

5. A compressor as claimed in one of the preceding Claims, characterised in that extending between the insertion point (4) and the insertion opening of said position (25) is a passage (13, 20) with a first mouth, which is adapted to be connected to the insertion point (4) and a second mouth (21) which is adapted to be connected to the insertion opening, which passage is inclined from the first to the second mouth and is provided with a sensing device (15, 16, 19) which is adapted to detect the character of the tin (9) fed in and a cover device (17, 22) which is connected to the sensing device so that when this indicates a tin of a predetermined accept character the cover device (17, 22) is changed over from a position shutting off the passage of the tin to an open position so that the inserted tin passes to said position (250 as a result of the inclination of the passage (13, 20).

6. A compressor as claimed in Claim 5, characterised in that the sensing device comprises, on the one hand inductive members (19) to detect the material of the tin (9) and inductive members (15, 16) to detect at least one dimension thereof.

7. A compressor as claimed in Claim 1, characterised in that the power device (32) is equipped with a power sensor (46) which, when a predetermined maximum force for displacement of the walls (26, 29) in relation to one another is exceeded, acts on a device (28, 36) to remove the object from the position (25), the compression of which object gave rise to said exceeding of the predetermined maximum force.

8. A compressor as claimed in Claim 7, characterised in that the position is formed from a first end wall (26.)and a second end wall (29) forming said displaceable walls, which latter end wall (29) is displaceable by means of the power device (32), and extending between the end walls,a first side wall ( 27) and a second side wall (28) which are inclined and form a substantially V-shaped bottom constituting the position (25) which is open at the top, the first side wall (27) being fixed and provided with said discharge opening (30) close to the first end wall (26) and the second side wall (28) being displaceable by means of a power device (36) so that the position can be opened for the discharge of the object which gave rise to said exceeding of the predetermined force value, and the object obtains a downwardly directed - laterally directed movement through the inclination of the first side wall (27), which direction of movement differs from the direction of movement of compressed objects falling out through, the discharge opening (30).