GB2373234A

GB2373234A - Apparatus for manufacturing resealable packages

Info

Publication number: GB2373234A
Application number: GB0106532A
Authority: GB
Inventors: Mark Jeremy Blackman
Original assignee: STICKPACK EUROP Ltd
Current assignee: STICKPACK EUROP Ltd
Priority date: 2001-03-16
Filing date: 2001-03-16
Publication date: 2002-09-18
Anticipated expiration: 2021-03-16
Also published as: GB0106532D0; GB2373234B

Abstract

A continuous sheet 22 of packaging material is driven through a cutting station 24, a patch applying station 26, and a forming and filling station 32 to produce a succession of tubular packs of product 38, e.g. sugar or coffee granules, each having a dispensing opening (18, fig. 4) covered with a resealable adhesive patch (12, fig. 1). The cutting station includes a roller 40 having blades or knives 72 extending over part of the roller in order to produce a cut (10, fig. 1) of predetermined profile on the sheet, with control means 68 which synchronises the roller and sheet speeds whilst they are in contact. The apparatus may include means 70 to trigger the control means 68 upon sensing a periodic reference on the sheet, and the cutter may include a second roller 42 having hardened lands 74 which mate with the cutting blades. The patch applicator 26 may include a guide blade (86, fig. 8) which peels patches (82, fig. 8) from a backing sheet and applies them to the sheet (22, fig. 8), with timing means (94,96,98, fig. 8) which sense the periodic references and drive the backing sheet around the guide blade so as to apply the patch at the correct place over the cuts formed by the cutting station.

Description

APPARATUS FOR MANUFACTURING PACKAGED PRODUCTS The present invention relates to apparatus for manufacturing packaged products and, in particular, to apparatus for manufacturing a package comprising a tubular container sealed at opposite ends and containing a liquid or flowable solid in particulate or granular form. Such containers, which contain a single dose or shot of product, such as sugar or coffee granules, are commonly known as stickpacks.

Machines for manufacturing stickpacks generally comprise a support for supporting a roll or pre-printed packaging, film or sheet. The sheet is then drawn through a cutting station where the sheet is severed, typically, into five ribbons. Each ribbon is guided around a downwardly extending tubular filling chute into a tubular profile in which mating opposite sides of the resulting tube are progressively sealed together. The bottom of the tube is then sealed following which a discrete quantity of product is discharged down the chute to fill the waiting tube. As the filled tube moves away from the lower end of the filling chute, the top of the tube is sealed and severed from the end of the ribbon to release a complete stickpack. Simultaneously, with this action the bottom of the next tube or package is sealed which is then processed in a similar manner to the severed tube or package.

The severing and sealing of each stickpack can be adjusted as required to produce stickpacks of different length.

Likewise, the discrete quantity of product discharged down each filling tube can be regulated as required.

With the advent of a stickpack with a resealable closure described and claimed in copending application filed by the same applicants and on the same date, it has been necessary to introduce into the machine for manufacturing stickpacks means for producing a discharge opening and a resealable closure for such an opening. It is an object of the invention to provide an improved apparatus for manufacturing packaged products.

According to the invention, there is provided apparatus for manufacturing packaged products, comprising means for driving a continuous sheet of packaging material in succession through a cutting station, a patch applying station and a forming and filling station at a constant speed to produce a succession of tubular packs of product, the cutting station including a roller carrying a cutting blade extending only over a predetermined arc of the roller to produce a cut of predetermined profile in the sheet, and control means for periodically increasing the speed of rotation of the roller to bring the peripheral speed of the cutter into synchronisation with the speed of the sheet during the period that the cutter engages the sheet.

Apparatus for manufacturing packaged products, will now be described, by way of example with reference to the accompanying diagrammatic drawings, in which: Figure I is a front elevation of a first embodiment of a stickpack ; Figure 2 is a rear elevation of the stickpack of Figure 1;

Figure 3 is a side view of the stickpack of Figure 1 ; Figure 4 is a detail to an enlarged scale of Figure 1 ; Figure 5 is a block diagram of the apparatus; Figure 6 is a front elevation of the cutting station of the apparatus of Figure 5; Figure 7 is a front elevation of the cutting station of Figure 6 in the cutting mode; Figure 8 is a front elevation of the patch applying station of the apparatus of Figure 5.

The stickpack shown in Figures 1 to 4 comprises an elongate tube 2 of impermeable plastics sheet or film having an elongate longitudinal seal 4, formed by heat sealing the opposite longitudinal sides of a rectangular piece of the sheet of film together. Instead of heat-sealing, an adhesive may be used.

The lower axial end region 6 of the tube is also heat sealed as also is the upper axial end region 8 after the tube has been filled or partially filled with the desired contents.

A semicircular cut 10 is provided in the wall of the tube adjacent the upper axial end region 8.

A circular patch 12 which is coated on one face with a resealable adhesive is adhesively secured over the cut 10. The circular patch 12 has a diameter which is greater than the diameter of the cut 12 and is generally applied so that it has a common centre with the cut 10. The patch 12 has radially extending tab 14 which is arranged to lie on the same

side of the common centre as the cut.

In operation, when the tab 14 is gripped and displaced away from the tube 2, it will progressively release itself from the tube 2 with the release line or front progressively moving towards the cut 10. When it reaches the cut, the semicircular part 16 of the tube 2 attached to the patch 12 will remain adhesively secured to the patch 12 and start to be pulled away from the rest of the tube to progressively open a discharge opening 18 in the tube (see Figure 4). Meanwhile the release front will travel on opposite sides of the semicircular cut 10 until the extremities of the cut are reached. Because during this phase only two narrow strips of the patch on opposite sides of the cut are being release from the tube, the peeling force required is relatively low. However, once the front has reached the extremities of the cut, the release front now faces the full diameter of the patch and immediately there is a significant jump in the peeling force required to effect further peeling. This is usually sufficient to cause the average user to halt any further peeling action.

The contents of the tube 2 can now be fully or partially discharged through the resulting opening 18. When the discharge action is discontinued, the user can now reverse the operation and push the peeled part of the patch 12 back into place. The semicircular portion 18 of the tube 2 which has adhered to the patch forms a plug to effectively plug the semicircular opening, it also prevents the contents of the tube adhering to the part of the patch which it covers. The part of the patch surrounding the semicircular part of the tube will now reseal itself against the tube thus locking any remaining contents within the tube

for reuse at a later date or for disposal without further leakage there from.

The cut 10 is not limited to a circular profile but can have any other profile, for example arcuate, zigzag or even linear.

Figure 5 is a block diagram of a machine for making the stickpack of Figures 1 to 4.

The machine is a five lane machine for producing five lanes of stickpacks. A supply roll 20 of plastics packaging sheet 22 has sufficient width for it to be cut into five ribbons 22 of equal width with each ribbon being ultimately destined to produce a respective line of stickpacks. The supply roll 20 thus carries five identical rows of printed matter which will ultimately be displayed by the resulting stickpacks. Included in the printed matter for each stickpack is a reference marker or indicator so that subsequent indexing of the material with the reference marker or indicator can take place.

The sheet 22 is drawn off the supply roll 20 through a cutter 24 which effects five semicircular cuts at a time in the sheet 22, one cut for each portion of the sheet that is destined to be formed into a single stickpack. The sheet then passes through a patch applier 26 with applies respective patch, covered with a resealable adhesive over each semicircular cut.

The sheet 22 then passes through a slitter 28 which slits the sheet into five separate ribbons 30. Each ribbon 30 is then fed to a former and filler 32 which forms the ribbon into a tube and fills it with a shot of product from a product source 34. A sealer and severer 36

seals the top and bottom of each tube and severs the connection between adjacent tubes to discharge the complete stickpack 38.

The cutter 24 is shown in more detail in Figure 6. The cutter 24 comprises two mating rollers 40 and 42 each having a respective central annular recess 44 and 46 slightly wider than the width of the sheet 22. The combined depth of the recesses 44 and 46 is slightly greater than the thickness of the sheet 22. Therefore, as can be seen from the drawing, the sheet 22 is free to be drawn through the rollers 42 and 40 when the rollers are inactive.

The rollers 40 and 42 have respective shafts 48 and 50 carried by respective pairs of bearings. Springs 52 and 54 between corresponding bearings urge the two rollers 40 and 42 into contact with one another but allow them to separate slightly against the bias of the springs 52 and 54 when required. Each shaft 48 and 50 carries a respective gear 56 and 58 which mesh with each other and with a drive gear 60. This ensures the synchronous operation of the two rollers 40 and 42 when driven by the gear 60. The gear 60 is carried on the drive shaft of a drive motor 62. A position indicator 64 carries a gear 66 which meshes with the gear 60 to indicate the angular position of the rollers. A controller 68 responds to a sensor 70 sensing a reference mark on the sheet 22 to drive the motor 62 and responds to the output of the position indicator to halt or reduce the drive to the rollers 40 and 42 when they reach a particular angular position.

The roller 40 carries a row of axially spaced semicircular cutter blades or knives 72

in the recess 42 extending along a common line which, as shown in Figure 6, lies on the diametrically opposite side of the roller 40 to the location of the sheet 22.

The roller 42 carries a row of axially spaced lands 74 of hardened material extending along a common line which, as shown in Figure 6, lies on the diametrically opposite side of the roller 40 to the location of the sheet 22. Each land 74 is arranged to cooperate with a respective knife 72 when the rollers 40 and 42 are rotated through 180 (see Figure 7).

In operation, the sheet 22 moves at a constant speed between the rollers 40 and 42.

When the sensor 70 detects the reference marker on the sheet, the controller 68 will drive the two rollers 40 and 42 into synchronisation with the speed of the sheet. At this time, the knives 72 will progressively mate with respective lands 72 to progressively sever the sheet 22 to produce the semicircular cuts therein. Shortly after the knives 72 have disengaged the lands 74 as detected by the position sensor 62, the controller 68 will discontinue the drive to the rollers 40 and 42 and the knives and lads will remain outside of the path of the sheet 22.

It will thus be appreciated that the rollers 40 and 42 are driven each time a reference marker on the sheet is sensed. Thus, the position of the semicircular cuts on the sheet is automatically changed according to the spacing between successive reference markers and that the machine does not need to be stopped for it to be adjusted to cope with a change the length of the stickpacks.

The sheet 22, with the semicircular cuts therein, then passes through the patch applier 26 which is more clearly shown in Figure 8.

A supply roll of substrate 80 carrying patches 82 in rows of five across is guided by a roller 84 to a guide blade 86 which causes the substrate to reverse direction by almost 360 . The patches 82 which adhere to the substrate 80 through the resealable adhesive which they carry, can no longer adhere to the substrate 80 during this manoeuvre and so progressively peel off the substrate and are directed into contact with the sheet 22 as it passes below the blade 86. The patches are discharged in a manner so that each pitch covers a respective cut in the sheet.

On leaving the blade 86, the substrate passes around a guide roller 88 and is then directed between a pair of mating drive rollers 90 and 92. The drive rollers 90 and 92 are

driven in a'succession of progressive steps by a stepper motor 94.

The stepper motor 94 is controller by a controller 96 which responds to a sensor 98 sensing a reference mark on the sheet 22 as it approaches the blade 86. The controller 96 also responds to a detector 100 which senses the arrival of the leading edge of a patch at a particular location and operates to synchronise the discharge of a patch with the displacement of the sheet 22. In this way, the deposit of a patch on each semicircular cut on the sheet 22 is ensured. As with the cutter 24 it can be seen that the patch applier automatically adjusts itself to applying patches to different lengths of stickpacks without the need to stop the machine to effect the adjustment.

While the machines which has been described as producing five lines or lanes of stickpacks, it will be appreciated that the machine can be adapted to produce only a single line or more or less than five lines of stickpacks.

Also, as will be appreciated, while the cuts have been described as being semicircular, the blades can be profiled to produce arcuate, zigzag or even linear shaped cuts outs.

Claims

CLAIMS 1. Apparatus for manufacturing packaged products, comprising means for driving a continuous sheet of packaging material in succession through a cutting station, a patch applying station and a forming and filling station at a constant speed to produce a succession of tubular packs of product, the cutting station including a roller carrying a cutting blade extending only over a predetermined arc of the roller to produce a cut of predetermined profile in the sheet, and control means for periodically increasing the speed of rotation of the roller to bring the peripheral speed of the cutter into synchronisation with the speed of the sheet during the period that the cutter engages the sheet.
2. Apparatus according to Claim 1, including sensing means for sensing a periodic reference on the sheet as it passes a predetermined fixed location, to trigger said control means to effect said synchronisation on each detection of a reference by the sensing means.
3. Apparatus according to Claim 1 or to Claim 2, including a second roller mating with said first mentioned roller and controlled by said control means, said second roller having a land of hardened material that periodically mates with the cutting blade at the nip between the two rollers when they are driven together.
4. Apparatus according to Claim 3, wherein the cutting blade and the land project from respective recesses in said first and second rollers respectively and wherein said rollers are so mounted that a limited amount of axial separation can take place between them.
5. Apparatus according to Claim 3, wherein said first and second rollers have corresponding annular recesses so that at the nip between the rollers, the combined recesses define a spaced through which said sheet can travel unhindered, said blade and said land being located within said recesses so as to engage with said sheet only during a fraction of each full rotation of said rollers.
6. Apparatus according to any preceding claim, including means for monitoring the rotation of the first roller and providing a feedback signal to the control means.
7. Apparatus according to any preceding claim, wherein said cutting blade is arcuate to produce an arcuate cut in said sheet.
8. Apparatus according to any one of Claims 1 to 7, wherein said patch applying station comprises supply roll means for supplying a roll of carrier sheet bearing a linear array of patches which adhere thereto with the aid of a resealable adhesive carried by said patch, a guide blade located adjacent the path of the packaging sheet through the patch applying station, guide means for guiding the carrier sheet around the guide blade at an angle sharp enough to cause the patches to peel off the carrier sheet at that point and to transfer to the adjacent packaging sheet, a sensor for sensing the periodic reference on the packaging sheet, and drive means to drive the carrier sheet around the guide blade each time the sensor senses the periodic reference.
9. Apparatus according to Claim 8, wherein the drive means comprises a pair of

mating rollers downstream of said guide blade which engage said carrier sheet, and a stepper motor triggered by said sensor to drive the carrier sheet.
10. Apparatus according to Claim 9, including a detector located upstream of the guide blade to sense the passage of patches on said sheet there past, and control means for controlling said stepper motor to synchronise the displacement of the carrier sheet with the sheet of packaging material so that said patch is deposited on said sheet of packaging material to cover a corresponding cut therein.
11. Apparatus for manufacturing stickpacks substantially as hereinbefore described, with reference to the accompanying drawings.
12. A stickpack manufactured, the apparatus according to any preceding claim.

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