WO2006117559A1

WO2006117559A1 - Removing a cap rim from a container

Info

Publication number: WO2006117559A1
Application number: PCT/GB2006/001621
Authority: WO
Inventors: Gerald John Evans
Original assignee: Evans Gerald J
Priority date: 2005-05-05
Filing date: 2006-05-03
Publication date: 2006-11-09
Also published as: GB2440866B; GB0722244D0; GB2440866A

Abstract

A method of removing a cap rim (2) from a container rim (50) wherein a first part (3) of the cap rim lies inside the wall (4) of the container (1) to which the container rim is attached, a second part of the cap rim is between the wall of the container and the container rim and a third part of the cap rim extends between the first and second parts of the cap rim around around the outside of the container rim by forming at least one cut (5) in the first part of the cap rim; folding the first part of the cap rim to a position outside the interior of the container; forming at least one break in the cap rim, said break being in the second and third parts of the cap rim and being aligned with the at least one cut; and pulling the cap rim from the container rim, the direction of pulling having at least a component radial of the container. An apparatus for performing the method is also disclosed.

Description

REMOVING A CAP RIM FROM A CONTAINER

Background of the Invention Field of the invention

The present invention relates to a method of removing a cap rim from the rim of a container, such as a food or beverage can. It is particularly, but not exclusively, concerned with removing that rim when the container has already been used, and the majority of the cap has already been removed to permit the contents of the can to be reached. The present invention also relates to an apparatus for removing a cap rim.

Summary of the Prior Art

Present metal recycling methods of recycling food and beverage cans is inadequate- and causes unnecessary - use of energy, water, fossil fuels, chemicals creating greenhouse and carbon gas emissions escaping into the atmosphere adding to global warming. My concept is to eliminate those problems by not recycling cans but refurbishing by reconditioning and this type of food^' receptacle.^' There are 38 billion beverage cans and an equal amount of food cans sold in Europe, worldwide I estimate the usage to be between 400 - 600 billion per annum. This concept will, at first apply mainly to _.the round cylinder shaped can but could apply to other shapes at a later date, as^' the principle is the same. I will firstly describe what is happening to the can when de- rimming takes place and then secondly the method and tooling operation during the de-rimming process. Fig 1 illustrates the configuration of a can prior to it being filled with soup or other produce and before the final seal cap has been fitted. For clarity the edge of the wall thickness of the can 1 is depicted with a diagonal upward and downward stripe. Modern cans have metal caps that are crimped onto the can by folding the top edge 3 of the wall of the can 1 and intertwining it with the edge of the sealing cap rim 2, this intertwining is shown in a cross section drawing Fig 2 of this application which illustrates an empty can with the ring pull seal or centre section of the lid removed by other suitable means and -only a rim 2 of the lid remaining. The rim 2 is shown in also an exaggeration of wall thickness depicted by a ^λtrellis' infill for clarity. It illustrates how the cap and the body of the can are formed together to achieve a seal. The rim is obviously more compact than shown in the drawing, as in practice; all the faces of the metal cap and can would be compressed together to prevent leakage and a sealant would be used between the faces to improve the chances^' of a seal.

When a can is filled with a product such as baked beans, soup or fruit a metal seal cap is .fitted to the top of the can. This cap is usually either a lid that is removed with the aid of a tin opener or it has a ■ '^■ proprietary ring-pull seal, which when removed leaves the rim section of the cap attached to the can. The can when empty is a perfectly good container but without a seal.

Summary of the Invention The present invention seeks to return the can to the same configuration it was prior to having the cap fitted, as shown in Fig. 1, by removing the remaining part of the rim 2 from the can. It is then possible to re-neck, sterilise and re-lacquer the can so it may then be as_ good as new. It may then be filled and capped again. This produces a new can with no material costs, and virtually no production costs.

Thus, at its most general, the present invention proposes that part of the rim inside the can is cut, preferably with a plurality of cuts, to enable that part of the rim to be lifted clear of the interior of the can. The rim can then be removed from the container by pulling it outwardly, which would not be possible without damaging the can if the part of the rim within the can had not been moved first .

Therefore, according to a first aspect of the present invention there is provided a method of removing a cap rim from a container rim, the cap rim being initially intertwined on the container rim such that a first part of the cap rim lies inside the wall of the container to which the container rim is attached, a second part of the cap rim is between the wall of the container and the container rim and a third part of the cap rim extends between the first and second parts of the cap rim around the outside of the container rim; the method comprising: forming -at least one cut in the first part of the cap rim; folding the first part of the cap rim to a position outside the interior of the container; forming at least one break in the cap rim, said break being in the^' second and third parts of the cap rim and being aligned with the at least one cut;^' and pulling the cap rim from the container rim, the direction of pulling having at least a component radial of the container.

Preferably, a plurality of cuts are formed in the first part of the cap rim as this makes it easier to lift that first part clear of the can. The first part may be folded to a position where it is axial of the container, i.e. extends vertically if the container is upright, it may then be further folded to a position which it is inclined to the axis container, and lies outwardly of the container. This means that the first part of the cap rim is then easier to grip, e.g. by a device which pulls the rim off the container.

In order to move the first part of the cap rim, a mandrel may be inserted in the container, to lie axially inwardly (i.e. further away from the container rim) than the first part of the cap rim. The mandrel may then be moved axially out of the container, such movement then causing the folding of the first part of the cap rim. That mandrel may also carry one or more blades which carry out the⁶ cutting of the first part of the cap rim prior to folding.

According to a second aspect of the present invention there may be provided an apparatus for removing a cap rim from a container rim, the cap rim being initially intertwined on the container rim such that a first part of the cap rim lies inside the wall of the container to which the container rim is attached, a second part of the cap rim is between the wall of the container and the container rim and a third part of the cap rim extends between the first and second parts of the cap rim around the outside of the container rim; the apparatus comprising: a cutting device for forming at least one cut in the first part of the cap rim; a mandrel for folding the first part of the cap rim to a position outside the wall of the container; ^' a device for forming at least one break in the cap rim, said break being in the second and third parts of the cap rim and being aligned with the at least one cut; and a device for pulling the cap rim from the container rim, the direction of pulling having at -least a component radial of the container.

Thus, with the present invention, it is possible to re-use the container,^' which may eliminate the present waste for recycling methods that use energy, . or watering chemicals and still cause considerable pollution. At the same time it may eliminate mining for ore, thereby reducing greenhouse gas emissions, since reusing of the container eliminates the need to make a new container for the same purpose. Containers could be reused not once, but possibly three or four times.

Brief Description of the Drawings

The embodiments of the present invention will now be described in detail, by way of example, with reference to the accompanying drawings in which;

Fig. 1 is a sectional view through a container such as a can;

Fig. 2 shows the container of Fig. 1, but in which part of the cap remains on the container;

^• Fig. 3 shows a first stage in the removal of the cap rim, in which cuts are made in the cap rim; Fig. 4 is a view of another stage in the removal of the cap rim;

Fig. 5 illustrates a further bending of part of the cap rim; Fig. 6 is another stage in the removal of the cap rim;

Fig. 7 shows the container of Fig. 2, in which the cap rim has been wholly removed;

Figs. 8 and 8A illustrate a mandrel for use in the removal of the cap rim;

Fig. 9 illustrates the action of that mandrel;

Fig. 10 shows the mandrel of Fig. 8 and its support;

Fig. 11 shows the action of a further mandrel to cause the folding of the cap rim to the position shown in Fig. 6;

Fig. 12 illustrates the action of that mandrel;

Fig. 13 shows the removal of the cap rim, corresponding to Fig. 7;

Figs. 14 to 20 illustrate part of the mandrel of Fig. 8.

Detailed Description

The only way to unravel the remaining part of the rim 2 from the can 1 is to move the internal diameter edge 3 of the rim 2 beyond the outside diameter 4 of the can 1 and this is probably only possible if the rim 2 is cut 5 as shown in fig 3 in one or more times to create two or more sections and each section 6 is first of all lifted into a vertical position as in fig 4 and illustrated and by the dotted line sections 6 in fig 5 and then pressed downwards outside as shown by the arrow

7 of the can 1 fig 5, to a suitable angle ready for removal, again illustrated in fig 6. Without the rim 2 being severed it would cause the can 1 to buckle inwardly at the top and would damage it beyond repair. To attempt to remove the rim without cutting would be likely to caused irreparable damage to the can. Another method would be to have cutting teeth 78. on the top phase 18 of the shoulders 13 so that as the mandrel 9 is withdrawn it cuts the rim in one movement as shown in 18A and drags the rim 2 into a vertical position. Thus, in the present invention, the forming of at least one cut in the first part of the cap rim and the folding of that first part of the cap rim may be carried out in a single action.

To remove the cut rim 2 from the top edge 50 fig 1 of the can 1 you will see by the direction of the arrow 8 in fig 7 that a removal mechanism would have to pull the rim 2 outwards to separate it from the can. This action would also lift the top edge 50 of the can 1 sufficiently ready for the can to be transferred to a necking machine for re-necking. You will see the comparison of the top edge of the can 50 having been removed and the shape it was 66 fig 7 when intertwined with the rim 2 when attached to the can 1 and 67 fig 7 illustrates the shape of the rim 2 when attached to the can 1 in and intertwined with the top edge 50 of the can 1 _.compared with what the rim 2 now looks like ^' having been removed.

I will now explain the operation and tooling of how the de-rimming operation is^'' carried out and tooling involved. The tooling could be used on one or more different types of machines, with some modifications, but the action of the tooling will remain the same. Fig 8 illustrates a mandrel 9 that has a top section 10 and. a bottom section 11 that are held together by preferably by one or more bolts 12. Between these two sections are trapezoid type shoulders 13 that move inwardly and outwardly with the aid of one or more springs suitably positioned to cause this action. Two such positions are shown as 14 and 15. The spring 14 could be held in a hole 16 in housing 17 on the top face 18 of shoulder 13 with the other end of the spring 14 against the inner face 19 of the top section 10 of the mandrel 9. This spring system could be made to work on the underside face 20 of the shoulder 13. Another suitable position for the spring system could be the outside face 21 of shoulder 13. In this drawing a groove 22 in the outside face 21 of the shoulder 13 contains a spring 15 that goes circumferentially around all of the shoulders 13, this is also illustrated in fig 17. These springs can be of any suitable design flat, coiled or any other design. The position taken up by the shoulders 13 when moved outwards is illustrated by the dotted line 23 and the extent of travel required. Inner faces 24 of the shoulders 13 fig 8 are chamfered to mate with the chamfered face 25 of the central spindle 26. To make the shoulders 13 move outwards and retract as shown in 23 the spindle 26 moves up and down as shown by the arrow 27 through a central hole 75 in the top section 10 and another central hole 76 in the bottom section 11. When pulled up the face 25 on the spindle 26 meets the chamfered face 24 on the shoulder 13 and is pushed outwards when the spindle is lowered the faces separate and the spring either 14 or 15, whichever system is being used retracts the shoulders 13 back into the mandrel 9. Fig 9 illustrates the first stage of removal of the rim 2 from the can 1. The mandrel 9 has been lowered into the can 1, passing the internal rim 3 of the rim 2, so that the top face 18 of the shoulder 13 sits under the curved edge 30 of the rim 2. The lowering of the mandrel 9 is done using standard production machines, not shown, that are connected to rods 77 fig 8 or other suitable fixing to enable the lowering of the mandrel 9 into position. When the shoulders 13 are extended it is important that they are uniform in their movement and for this purpose the spring housing 17 acts as a guide by sliding in grooves 58 fig 20 and fig 8 cut into preferably the top section 10 of the mandrel 9 as shown in fig 8 and fig 19. Another method of controlling the shoulders 13 would be to have a pin 28 fig 9 on the underside face 20 of the shoulder 13 that runs in a slot

29 in the bottom section 11 of the mandrel 9 in fig 9 and also shown in fig 20. It will be obvious that if the chamfers 24 on the spindle 26 and chamfer 25 on the shoulder 13 were reversed so that spindle 26 came downward forcing the shoulders 13 outwards under rim 2 at 30 the shoulders would react in the same way as shown in fig 8a. It is the concept of moving shoulders, however done, under the rim 2 to position 30 to lift the sections 6 to a vertical or other suitable position to allow the removal of the rim from the can that is the original concept.

Having moved the shoulders 13 out under the rim 2 at

30 a cutter tool 31 fig 10, that slides up and down as shown by the arrows 35 and 36 on the rods 77 fig 8 and the central, spindle 26 through holes 33 and 34 respectively, having several cutting teeth 32 slides over the outside face 37 fig 9 and illustrated by the arrow in the dotted lines 70 fig 10 of the mandrel 9 until it comes into contact with the rim 2 as shown in fig 10 and fig 18. It then proceeds to slice through the rim 2 acting like a guillotine cutting the rim in several sections 6 as shown in figs 3 to fig 7. It will be noted that the teeth 32 are chamfered at the back edge 38 fig 10. This aids the cutting of the rim 2 as the face 39 of the teeth 32 rub close to or against the back edge 52 fig 15 & 16 of the shoulder 13 in front and with the rim 2 sandwiched between the teeth 32 and the top face 18 of the shoulder shearing the rim as shown in fig 17. To ensure the rim 2 is cut through cleanly a chamfered face 40 figs 10, 15 and 16 that matches the angle of the back edge 38 fig 10 of the teeth 32 is on the shoulders 13 fig 10 so that the cut can carry right through the rim 2.

The cutter tool 31 is then withdrawn clear of the mandrel 9 but the shoulders 13 of the mandrel 9 stay extended under rim 2 at 30. The mandrel is then removed from the can 1 as shown by the directional arrow 68 lifting the sections 6 as illustrated by. the arrow 69 until the sections 6 are vertical as in shown in fig 9 by dotted lines. During withdrawal it may rotate and extend the shoulders 13 further as the underside 21 of the shoulders reach the top of the canl. It will then be completely withdrawn. During all these operations the can 1 has been held in a chuck or collar 41 fig 9, which could be electro magnetically operated if required for two part cans and could be in two or more sections extending above the rim of the can if required. As the mandrel 9 is pulled upwards or the chuck 41 is pulled downwards, the extended shoulder 13 catching and lifting the curved section 30 of the rim 2 pull the sections 6 of the cut rim.2 upwards into a vertical position as shown by the arrow in fig 9. The mandrel is then brought clear of the can and the can moves to the next operational point. To move the sections 6 of the rim 2 to their next position as illustrated in fig 5 and fig 6 the can is again held in a collar or chuck 42 with an angled face

43 as shown in figure 11. A solid mandrel 44 with a matching face angled face 45 of the face 43 on the chuck or collar 42 comes down, as shown by the arrow 51, into the can 1 and as the angled face 45 of the mandrel 44 comes into contact with the sections 6 of the rim 2 it forces them outwards against the angled face 43 compressing them between the two angled faces 43 and 45 faces as illustrated in fig 12. The sections 6 are now in a position for final separation from the can 1.

In fig 13 the method of final separation is illustrated. A vice type apparatus 46 consisting of one or more clamps working separately or in conjunction with each other, preferably being made up of two clamping blocks or jaws 47 and 48 that grip the sections 6 of the rim 2 firmly and then pull the section 6 of the rim outwardly, as shown by the arrow 49 -and 74. This pulling action breaks the circular rim 2 at the same time lifting the^' top edge 50 as shown in fig 1 and fig 7 away from the can 1. To prevent distortion of the can during this operation a solid mandrel similar to mandrel

44 fig 12 is inserted into the can whilst also being held in a collar or chuck 41 fig 9. In this illustration it shows the vice type apparatus hinged and the jaws 47 and 48 compressing the rim sections 6 ready for separation from the can. As long as there are two or more jaws 47 and 48 whatever method used to hold the can to separate the rim 2 from the can 1 the design is irrelevant. Bringing the two jaws together can be done in many ways. In this instance a hinged device 71 is used and the arrows 72 and 73 illustrate the movement of the two parts 47 and 48. The concept of having a series of pairs of jaws coming together to grip the sections 6 of the rim 2 to enable its removal from the can 1 is the original concept.

Figs 14 W and ^ΛB' illustrate the shape of the shoulders 13; when they are together in the mandrel 9 the gaps 53 fig 15 shown shaded provide a space 53 through which the bolts 12 fig 8 pass when the top and bottom sections 10 and 11 fig 8 of the mandrel 9 are bolted together. In top section 10 are the boltholes 56 through which the bolts pass and in section 11 are the threaded boltholes 57 fig 8 and fig 20 into which the bolts are threaded. The arrows 54 on the shoulders 13 in figl5 illustrate the direction of the shoulders 13 moving outwardly. Another view of the internal spring housing 17 and spring 14 is shown in figs 15 and 16. Figs 17 and 18 show another elevation of the cutting action of the cutter tool 31. Fig 19 illustrates the grooves 58 that the spring housing 17 slides within to keep the shoulders 13 uniform and fig 20 show the slots 29 the guide pin 28 would move up and down the inside.

A further aspect of removing the rim 2 from a can 1 is the problem of removing the tops from beverage cans. Unlike ring-pull cans they only have small drinking holes 61 and therefore it is impossible to remove the top without carrying out another operation or two before being able to remove the rim. A simple method would be to have a further circle or diagonal lines scored 59 into the lid 60 shown in fig 21 similar to that used with the ring pull soup and baked bean can cap but without the ring pull mechanism. It would only go up to or close to the ring pull scoring cut in the beverage can. It could go the full circumference or part of the way round. Having revealed the drinking hole it would be large enough for a tool to be entered into drinking hole 61 in the can and have the tool rip off the top tearing at the scored section so that the previous operation described for removing the rim could be put into practice. Alternatively the cap could be scored sufficiently so that a tool could pierce the can whilst the top was held securely in a set of jaws to prevent the can buckling. Then removal could then begin as previously described. It is possible to use an alternative tool 62 manufactured in a solid form shown in fig 22 made from one or more parts to lift the rim. In this instance either the tool or the can would rotate whilst the tool lifted the rim 2 of the can 1 forcing it to a vertical position. The rim would be cut in a similar fashion as previously described but the leading edge 63 of this tool 62 would pierce through the cut rim 2 gathering up the rim onto the curling face 64 of the tool 62 it then passes between the vertical face 65 of the tool 62 and the inner vertical face of the 2 in a circular motion. This makes the rim 2 vertical and ready to be removed using the method previously described in figs 11,12 and 13. However, as previously claimed whatever type or design of shoulder is used to lift the sections 6 of the rim 2 a vertical or other suitable position to enable its removal is the original concept.

Claims

1. A method of removing a cap rim (2) from a container rim (50) , the cap rim being initially intertwined on the container rim (50) such that a first part (3) of the cap rim (2) lies inside the wall (4) of the container (1) to which the container rim (50) is attached, a second part of the cap rim (2) is between the wall (4) of the container (1) and the container rim (50) and a third part of the cap rim (2) extends between the first and second parts of the cap rim (2) around the outside of the container rim (50); the method comprising: forming at least one cut (5) in the first part (3) of the cap rim (2); folding the first part of the cap rim (2) to a position outside the interior of the container; forming at least one break in the cap rim (2), said break being in the second and third parts of the cap rim (2) and being aligned with the at least one cut (5); and pulling (49, 74) the cap rim (2) from the container rim (50), the direction of pulling having at least a component radial of the container.

2. A method according to claim 1, wherein at a plurality of cuts (5) are formed in the first part (3) of the cap rim (2) .

3. A method according to claim 1 or claim 2, wherein the first part (3) of the cap rim (2) is folded at least to a position where it is axial of the container (1).

4. A method according to claim 3 wherein the first part of the cap rim is further folded to a position where it is inclined to the axis of the container (1) and extends radially outwardly of the container (1).

5. A method according to any one of the preceding claims, wherein a .mandrel (9) is inserted in the container to lie axially inwardly of the first part (3) of the cap rim (2), and the mandrel (9) is removed axially out of the container,- thereby to cause said folding of the first part of the cap rim.

6₌ A method according to claim 5, wherein the cutting . of the first part of the cap rim (2) is by at least one blade (32) carried by said mandrel (9) .

7. A method according to any one of the preceding claims wherein the forming of the at least one break in the cap rim (21) is caused by a pulling action.

8. A method according to any one of the preceding claims, wherein said pulling of the cap rim (2) from the container rim (50) comprises pulling said first part (3) of the cap rim (2) .

9. An apparatus for removing a cap rim (2) from a container rim (50), the cap rim being initially intertwined on the container rim (50) such that a first part (3) of the cap rim (2) lies inside the wall (4) of the container (1) to which the container rim (50) is attached, a second part of the cap rim (2) is between the wall (4) of the container (1) and the container rim (50) ^' and a third part of the cap rim (2) extends between the first and second parts of the cap rim (2) around the outside of the container rim (50); the apparatus comprising: a cutting device (32) for forming at least one cut (5) in the first part (3) of the cap rim (2); a mandrel (9) for folding the first part (3) of the cap rim (21) to a position outside the interior (4) of the container (1); a device (46, 47, 48) for forming at least one break in the cap rim (2), said break being in the second and third parts of the cap rim (2) and being aligned with the at least one cut (5); and a device (46, 47, 48) for pulling the cap rim (2) from the container rim (50), the direction of pulling having at least a component radial of the container (1) .

10. An apparatus according to claim 9 further including an additional mandrel (44) for further folding the first part of the cap rim (2) from a position where it is axial of the container (1) to a position where it is inclined to the axis of the container (1) and extends radially outwardly of the container (1) .

11. An apparatus according to claim 9 or claim 10, wherein said mandrel (9) is insertable in the container

(1) to lie axially inwardly of the first part (3) of the cap rim (2), and the mandrel (9) is removable axially out of the container (1), thereby to cause said folding of the first part (3) of the cap rim (2) .

12. An apparatus according to any of claims 9 to 11, wherein said cutting device is formed by at least one blade (32) carried by said mandrel (9) .

13. An apparatus according to any one of claims 9 to 12 wherein the device (46, 47, 48) forming the at least one break in the cap rim (2) also forms the device (46, 47, 48) for pulling the cap rim (2) from the container rim (50).