DE102014001177A1 - Method and device for producing a container filled with filling material - Google Patents

Abstract

The invention relates to a method for producing a container (1) filled with a filling material, comprising the following method steps: forming a thermally conditioned container preform from a thermoplastic material into an intermediate container (2) by means of a blown or stretch blown method using the outer contour of the intermediate container (2) pre-existing blow mold (4), wherein the intermediate container (2) has a container wall (13) with an outwardly bulged Umstülpbereich (20); - filling the intermediate container (2) with a filling material; - closing the intermediate container (2); - Forming the intermediate container (2) in a container (1) by everting the Umstülpbereichs (20), so that the Umstülpbereich (20) in the container (1) is curved inwards. The invention further relates to an apparatus for producing containers (1) filled with filling material, in particular according to a method according to one of claims 1 to 7, comprising a filling device for filling intermediate containers (2) with a filling material, wherein the intermediate containers (2) respectively a container wall (13) with an outwardly bulging Umstülpbereich (20), the device further comprising a closing device for closing the container filled with filling intermediate container (2), the device further comprising an everting device (46, 47) for forming in each case an intermediate container ( 2) in a container (1) by eversion of the respective inversion area (20), so that the respective inversion area (20) in the container (1) is curved inwards.

Description

The invention relates to the production of containers filled with contents, wherein the containers are produced by forming a thermally conditioned container preform from a thermoplastic material by means of a blown or stretch blow molding process.

For example, it is known to produce containers such as beverage bottles of polyethylene terephthalate (PET) or polypropylene (PP) or other known thermoplastics or thermoplastic materials. It has also been possible to produce such containers with sufficient temperature stability for filling with hot medium. In this case, the problem regularly arises that after filling and closing the container by contraction of the contents and by volume decrease of the remaining volume in the bottle-free volume during cooling, a negative pressure in the container.

In order to obtain a stable container despite this negative pressure, it is known in the prior art to provide so-called panels on the container, which are designed to deform plastically when pressure changes in the container interior and thereby compensate for the pressure change in the container interior. The areas between the panels, often referred to as ribs, but must be designed particularly dimensionally stable in order to ensure the stability of the container as a whole. This is usually ensured by the wall thickness of the container, so that the general desire for material and weight savings are narrow limits.

A second known method for equalizing a negative pressure in the container is to add a small amount of liquid nitrogen in the container immediately before closing, wherein the nitrogen then evaporates and causes an increase in pressure in the container. Here is exploited that the container is much easier to stabilize in terms of pressure by its shape than under negative pressure, inter alia because the material in the thin container wall can accommodate much larger tensile loads than compressive loads. However, it has been found that the internal pressure of the filled containers is very difficult to control with the addition of liquid nitrogen and is subject to large variations from container to container. Therefore, the containers must be designed to be stable according to safety reasons, in order to be able to cope with greater pressure inside the container without sacrificing stability. Here, too, narrow limits are set for thinner container wall thicknesses for saving material and weight.

Based on this prior art, the invention has the object, in the aforementioned containers, in particular in the field of hot filling to allow material and weight savings, without affecting the stability of the container.

• – Umformen eines thermisch konditionierten Behältervorformlings aus einem thermoplastischen Material in einen Zwischenbehälter mittels eines Blas- oder Streckblasverfahrens unter Verwendung einer die Außenkontur des Zwischenbehälters vorgebenden Blasform, wobei der Zwischenbehälter eine Behälterwandung mit einem nach außen gewölbten Umstülpbereich aufweist;
• – Befüllen des Zwischenbehälters mit einem Füllgut;
• – Verschließen des Zwischenbehälters;
• – Umformen des Zwischenbehälters in einen Behälter durch Umstülpen des Umstülpbereichs, so dass der Umstülpbereich im Behälter nach innen gewölbt ist.

This object is achieved by the invention by a method for producing a container filled with a product, comprising the following method steps:

• - Forming a thermally conditioned container preform of a thermoplastic material in an intermediate container by means of a blow or stretch blow molding using the outer contour of the intermediate container predetermined blow mold, the intermediate container having a container wall with an outwardly bulging Umstülpbereich;
• - filling the intermediate container with a filling material;
• - closing the intermediate container;
• - Forming the intermediate container into a container by everting the Umstülpbereichs, so that the Umstülpbereich is curved inward in the container.

The invention has the particular advantage that by everting the Umstülpbereichs a precisely predetermined change in volume between the intermediate container and the final container is achieved. By suitable design of the Umstülpbereichs thus a very precise predeterminable adjustment of the container volume of the volume loss of the contents is made possible during cooling, so that the internal pressure of the fully filled container is very precisely adjustable. Accordingly, the invention enables an optimal design of the container with minimal use of material and thus minimal container weight.

The everting region is for this purpose in particular designed such that there are two stable states for the container wall in Umstülpbereich, namely an outwardly curved state at the intermediate container and an inwardly curved state in the finished container. The everting region can in particular advantageously be arranged in the region of the container bottom.

During the everting, the container wall preferably has a temperature at least in the everted region which is less than a glass transition temperature of the thermoplastic material of the container preform or of the intermediate container or of the container. In this way, in particular prevents the container wall plastically deformed uncontrolled Umstülpbereich when everting. Also, by a temperature below the glass transition temperature a certain Resistance of the container wall against deformation achieved, so that an undesired return of the Umstülpbereichs from the after deformation desired, inwardly curved state with higher internal container pressure in the outwardly curved state with lower internal container pressure is reliably prevented, even if the deformation of Umstülpbereichs against an internal pressure takes place in the intermediate container or container, for example, because the contents is not yet cooled.

The inventive method is developed particularly advantageous if the intermediate container is filled with a hot medium, wherein the filled intermediate container and the contents, in particular after closing the intermediate container, is cooled to a temperature below the glass transition temperature of the thermoplastic material of the intermediate container.

In the context of the invention is meant by a hot medium in particular a product with a temperature of about 70 ° C, in particular of about 80 ° C, understood.

Furthermore, it is particularly advantageous within the scope of the invention if the container wall in the turnup region has dimensionally stable and / or dimensionally stable sections, between which, in particular reversible, deformable hinge sections are arranged.

As a result, in particular not the entire container wall is deformed in the area of the eversion area, but primarily the hinge areas. As a result, the force required to reshape the container wall is reduced in the eversion area and the controllability of the volume change from the intermediate container to the container is further increased. Advantageously, the totality of the hinge areas makes up at most half, more preferably at most one third, of the entire everting area.

The stable portions are formed, for example, dimensionally stable or dimensionally stable, for example, that the stable portions each have a curved surface in two different directions.

The hinge areas are designed, for example, deformable in that the hinge sections each have a flat or curved in one direction only surface.

The everting region is preferably arranged at a bottom of the intermediate container or the container. As a result, in particular unwanted impairments of the appearance of the container by the configuration of the Umstülpbereichs be avoided and an embodiment of the Umstülpbereichs primarily from a technical point of view, in particular with regard to the desired volume change and the achievable stability of the finished container allows.

The object underlying the invention is further achieved by a device for producing containers filled with filling material, comprising a filling device for filling intermediate containers with a filling material, wherein the intermediate containers each have a container wall with an outwardly bulging Umstülpbereich, the device further comprising a Closing device for closing the intermediate container filled with filling material, the device further comprising a Umstülpvorrichtung for reshaping each of an intermediate container in a container by eversion of the respective eversion, so that the respective eversion after the eversion in the container is curved inwards.

The device according to the invention is particularly suitable for carrying out the method according to the invention described above.

Preferably, the device according to the invention is further developed in that the device further comprises a conveying device arranged between the closing device and the eversion device for conveying intermediate containers closed by means of the closing device to the eversion device. In this case, the conveying device is preferably designed as a cooling device for cooling the filled intermediate container.

A suitable cooling effect can be achieved, for example, via a suitable length of the conveying device and a corresponding delivery time of the intermediate containers from the closing device to the forming device. In other embodiments of the invention, the conveying device has, for example, at least one suitable cooling device for cooling the filled and sealed intermediate containers. Suitable cooling devices use, for example, liquid cooling media, which are brought into contact with the intermediate containers and remove heat by convection and / or evaporation.

Further, the conveying device comprises, for example, grippers or pliers which engage in the mouth region of the intermediate container and carry along along a conveying path. However, high loads occur due to the weight of the filled intermediate container.

Alternatively, the intermediate containers are standing, for example by means of a belt conveyor of promoted the conveyor. However, this is only possible if the intermediate containers already have sufficient stability, for example, if the eversion area is formed at a different location of the container wall than at the bottom of the intermediate container, or the eversion area does not project beyond a standing area of the floor to the outside.

A particularly advantageous development of the device according to the invention is characterized in that the conveying device has at least one conveying pot for an intermediate container, wherein in particular the conveying pot has clamping means for the frictional retention of an intermediate container conveyed in the conveying pot.

As a result, a safe and easy promotion of the intermediate container is possible even in the absence of stability, without exposing individual components of the conveyor excessive mechanical loads.

The device according to the invention is supplemented, for example, in that the device further comprises a heating device for thermally conditioning container preforms and a blowing device for converting in each case a thermally conditioned container preform into an intermediate container by means of a blown or stretch blow molding method, wherein the blowing device has a blow mold predetermining an outer contour of the intermediate containers In particular, the device further comprises conveying means for conveying the intermediate container produced by means of the blowing device to the filling device.

This makes it possible, in particular, to carry out all steps of the method according to the invention in a single production line.

The object underlying the invention is also achieved by a container filled with a filling container, obtainable by a method according to the invention, in particular by means of a device according to the invention.

The object underlying the invention is also achieved by a blow mold for a device according to the invention. The blow mold according to the invention is in particular designed to be installed in a blowing device and to specify the outer contour of an intermediate container to be formed in a method according to the invention in a blown or stretch blow molding method using this blowing device.

The blow mold according to the invention preferably comprises two blow mold halves and a bottom mold.

In the drawings, embodiments of the invention are shown schematically. Show it:

1 1 schematically a blow molding station with a blow mold according to the invention,

2 schematically an intermediate container according to the invention in side view,

3 schematically a plan view of the bottom of the intermediate container 2 .

4 schematically a portion of a device according to the invention for the production of containers filled with contents, and

5 schematically an inventive filled with filling container, prepared according to the inventive method from the intermediate container 2 ,

1 shows a blowing station 3 for producing an intermediate container 2 in the context of a method according to the invention. The blowing station 3 includes a split blow mold 4 with two of mold holders 5 ' . 6 ' held blow mold halves 6 wherein, in the illustration, the second blow mold half of the mold holder 5 ' hidden and therefore not visible. The blow mold 4 may in the context of the invention also have other suitable divisions, for example with two blow mold halves 6 and a separate bottom shape.

In 1 the condition of the blowing station is shown 3 after blowing the intermediate container 2 , Corresponding blown or stretch blow molding methods are generally known in the prior art and therefore require no further explanation. The blow mold 4 is already open in the illustrated state to a removal of the finished blown intermediate container 2 to enable. In the illustrated embodiment, the intermediate container 2 and the corresponding, before blowing or stretch blow molding into the blowing station 3 inserted, container preform oriented overhead, ie with its open mouth area 11 pointing down. Other orientations, eg. B. with the mouth area 11 pointing upwards, are expressly also encompassed by the invention.

2 schematically shows an embodiment of an intermediate container 2 in side view. The intermediate container 2 consists of a complex shaped container wall 13 and is hollow in the interior for receiving a particular liquid filling. The intermediate container 2 includes a mouth section 11 and a bottom opposite the mouth portion 15 , On the ground 15 of the intermediate container 2 rejects the container 13 an outwardly arched eversion area 20 on.

3 schematically shows a plan view of the substantially cross-sectionally round bottom 15 of the intermediate container 2 out 2 , The floor 15 has a substantially annular base ring 16 and a concentric within the stand ring 16 arranged Umstülpbereich 20 on. The everting area 20 is also substantially round in cross-section and includes evenly distributed in the radial circumferential direction arranged stabilizing areas 22 and between the stable areas 22 arranged hinge areas 24 , The stable areas 22 are respectively formed by suitable measures, for example by a curved in two different directions surface, dimensionally stable or dimensionally stable. The hinge areas 24 however, in comparison to the stable areas 22 formed much easier deformable, for example by a flat or curved in one direction only surface.

According to the invention, the intermediate containers 2 filled with filling material, in particular hot filling material. Under hot is understood in the context of the invention, in particular a temperature between 70 ° C and 100 ° C. The hot filling in particular has the advantage that germs in the filling material and in the internal volume of the intermediate container are killed. The intermediate tanks 2 are then sealed according to the invention, for example by means of a respective cap 18 or another suitable closure means. From closing the intermediate container 2 decreases due to the contraction of the cooling charge the internal pressure. The trapped, filling-free volume also cools and takes up less volume. This pressure loss is inventively at least partially compensated that by everting the Umstülpbereichs 20 from an intermediate container 2 a container 1 is formed, wherein the container 1 as a result of the everting a smaller internal volume than the intermediate container 2 having.

4 schematically shows a forming wheel as part of a device according to the invention for the production according to the invention, filled with filling container 1 , The Umformrad be filled and sealed intermediate container 2 over a conveyor line 30 fed, the intermediate container 2 each individually by means of a processing station 47 the Umformrades 46 in containers 1 be transformed by the in the intermediate container 2 outwardly arched everted area 20 turned inside, for example, pressed, is.

Along the conveyor line 30 become the intermediate containers 2 in conveyor pots 32 promoted, each with an intermediate container 2 a funding pot 32 assigned. Within a funding pot 32 the corresponding intermediate container is preferably supported, for example by means of suitable, non-positively acting clamping lips. This effectively prevents the intermediate container 2 within the funding pot 32 tilted or even falls out of it.

On the conveyor line 30 become the funding pots 32 For example, in isolation, in particular with a constant conveying speed and / or constant separation distance from each other, moves, whereby the processing of the intermediate container 2 on the forming wheel 46 with the clock frequency of previous machines, such as a filler for filling the intermediate container 2 with the contents and / or a sealing machine for closing the filled intermediate container 2 , synchronized. However, the separation of the funding pots can also along the conveyor line 30 be lifted to some extent an asynchronous processing of the intermediate container 2 to allow on the mentioned machines. Preferably, the said devices operate in a continuous operation, as is usual with fillers, cappers or blow molding machines according to the rotary principle. In principle, however, the invention can also be carried out in devices operating in cycles.

From the conveyor line 30 become the funding pots 32 together with the intermediate containers 2 to the processing stations 47 the Umformrades 46 to hand over. Optionally, this is a screw conveyor 34 for separation of the funding pots 32 from the conveyor line 30 as well as an inlet wheel 40 to hand over the isolated funding pots 32 with the intermediate containers 2 to the forming wheel 46 or the processing stations 47 the Umformrades 46 intended.

On the forming wheel 46 become the intermediate containers 2 from the funding pots 32 taken and the empty funding pots 32 by means of a first outlet wheel 42 taken from the Umformrad and the conveyor line 30 fed. About the conveyor line 30 get the funding pots 32 back to the machines ahead and will again be with intermediate tanks 2 stocked.

In the respective processing station 47 the Umformrades 46 becomes an intermediate container 2 further by everting its eversion area 20 in a container 1 unformed. This processing step can before, during or after removal of the intermediate container 2 from the respective funding pot 32 respectively. Likewise, in the context of the invention, an eversion of the Umstülpbereichs 20 in the area A of Umformrades, ie before the delivery pot 32 , or in the area B of the blowing wheel, ie after the delivery pot has run out 32 , possible.

Finally, the finished containers 1 by means of a second outlet wheel 44 from the respective processing station 47 the Umformrades 46 removed and removed.

To illustrate the process described are directions of rotation of the wheels 40 . 42 . 44 . 46 as well as funding directions of the funding pots 32 with intermediate container 2 , the empty funding pots 32 as well as the container 1 each represented by arrows.

5 Finally, shows a container according to the invention 1 as obtained by the method according to the invention using the method described in 2 shown intermediate container 2 is available. To illustrate the shape of the eversion area 20 in the ground 15 of the finished, filled and with a cap 18 sealed container 1 the container is shown in the lower area as a cold cut.

LIST OF REFERENCE NUMBERS

1

container

2

intermediate container

3

blowing station

4

blow

6

blow mold

5 ', 6'

mold support

11

mouth area

13

container

15

ground

16

Standring

18

cap

20

turnup

22

stable range

24

hinge area

30

conveyor line

32

funding pot

34

Auger

40

infeed wheel

42

Spout wheel for conveyor pots

44

Outlet wheel for containers

46

Umformrad

47

processing station

Claims (15)

Method for producing a container filled with a product ( 1 ) comprising the following process steps: - forming a thermally conditioned container preform from a thermoplastic material into an intermediate container ( 2 ) by means of a blown or stretch blow molding method using a the outer contour of the intermediate container ( 2 ) prevailing blow mold ( 4 ), the intermediate container ( 2 ) a container wall ( 13 ) with an outwardly bulged Umstülpbereich ( 20 ) having; - filling the intermediate container ( 2 ) with a filling material; - closing the intermediate container ( 2 ); - forming the intermediate container ( 2 ) into a container ( 1 ) by everting the eversion area ( 20 ), so that the eversion area ( 20 ) in the container ( 1 ) is curved inwards. Method according to claim 1, characterized in that the container wall ( 13 ) during the everting at least in the everting ( 20 ) has a temperature which is lower than a glass transition temperature of the thermoplastic material of the container preform or of the intermediate container ( 2 ) or the container ( 1 ). Method according to claim 1 or 2, characterized in that the intermediate container ( 2 ) is filled with a hot filling material, wherein the filled intermediate container ( 2 ) and the contents, in particular after closing the intermediate container ( 2 ), to a temperature below the glass transition temperature of the thermoplastic material of the intermediate container ( 2 ) is cooled. Method according to one of claims 1 to 3, characterized in that the container wall ( 13 ) in the everted area ( 20 ) dimensionally stable and / or shape-stabilized stable sections ( 22 ), between which, in particular reversible, deformable hinge sections ( 24 ) are arranged. Method according to claim 4, characterized in that the stable sections ( 22 ) each have a curved surface in two different directions Method according to claim 4 or 5, characterized in that the hinge sections ( 24 ) each have a flat or a curved surface in one direction. Method according to one of claims 1 to 6, characterized in that the everting region ( 20 ) on a floor ( 15 ) of the intermediate container ( 2 ) or the container ( 1 ) is arranged. Device for producing filled containers ( 1 ), in particular according to a method according to one of claims 1 to 7, comprising a filling device for filling intermediate containers ( 2 ) with a filling material, wherein the intermediate container ( 2 ) each a container wall ( 13 ) with an outwardly bulged Umstülpbereich ( 20 ), the apparatus further comprising a closing device for closing the intermediate containers ( 2 ), the device further comprising an everting device ( 46 . 47 ) for forming in each case an intermediate container ( 2 ) into a container ( 1 ) by everting the respective everting area ( 20 ), so that the respective everting area ( 20 ) in the container ( 1 ) is curved inwards. Apparatus according to claim 8, characterized in that the device further comprises a between the closing device and the everting device ( 46 . 47 ) arranged conveying device ( 30 ) for conveying intermediate containers closed by means of the closing device ( 2 ) to the everting device ( 46 . 47 ). Apparatus according to claim 9, characterized in that the conveying device ( 30 ) as a cooling device for cooling the filled intermediate container ( 2 ) is trained. Apparatus according to claim 9 or 10, characterized in that the conveying device ( 30 ) at least one funding pot ( 32 ) for an intermediate container ( 2 ), in particular the funding pot ( 32 ) Clamping means for frictionally retaining a in the delivery pot ( 32 ) conveyed intermediate container ( 2 ) having. Device according to one of claims 8 to 10, characterized in that the device further comprises a heating device for thermally conditioning container preforms and a blowing device ( 3 ) for converting in each case a thermally conditioned container preform into an intermediate container ( 2 ) by means of a blowing or stretch blow molding method, wherein the blowing device ( 3 ) an an outer contour of the intermediate container ( 2 ) given blow mold ( 4 In particular, the device further comprises conveying means for conveying by means of the blowing device ( 3 ) produced intermediate container ( 2 ) to the filling device. Container filled with a product ( 1 ), obtainable by a method according to one of claims 1 to 7, in particular by means of a device according to one of claims 8 to 12. Blow mold ( 4 ) for a device according to claim 12. Blow mold ( 4 ) according to claim 14, characterized in that the blow mold ( 4 ) two blow mold halves ( 5 . 6 ) and a bottom mold.

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