METHOD AND DEVICE FOR FITTING A FIBER-BASED CONTAINER WITH A PREFORM AND FOR INTRODUCING THE CONTAINER INTO A BLOW MOLDING TOOL

Description

[0001] The present invention relates to a method for loading a fiber-based container with a preform, a device for loading a fiber-based container with a preform, and a method for inserting a fiber-based container together with a preform arranged therein into a blow molding tool according to the preamble of the independent claims.

[0002] Various containers for holding liquids are known in the prior art. For example, glass bottles or plastic bottles for holding beverages are known. Containers made of fiber-based materials have also been proposed.

[0003] US 2011 / 127141 Al, IT 2016 0012 8354 Al and US 3 893 882 A disclose methods and devices for conveying containers in a predetermined position, wherein the devices include rotary tables or conveyor belts.

[0004] EP 3 375 593 B1 discloses a method for loading a fiber-based container with a preform, comprising the steps Providing a container and placing a preform into the container.

[0005] A fiber-based container was proposed in WO 2012 / 139590 A1. To manufacture this container, so-called pulp is placed in a two-part mold and pressed against a corresponding wall of the mold using a flexible balloon, thus compressing it.

[0006] Pulp is a mixture of fibers and water, particularly natural fibers such as hemp fibers, cellulose fibers, or flax fibers, or a mixture thereof. The pulp may contain additives, such as those known from PCT / EP2019 / 076839, which, for example, improve the curing of the compressed pulp, influence its final appearance, or generally alter the properties of the pulp or the final container.

[0007] With these fiber-based containers, there is a risk that they will soften due to the liquid stored in the container and, for example, become leaky, or that substances from the container will diffuse into the liquid.

[0008] It has been proposed to equip such fiber-based containers with an inner layer of plastic, in particular to place a plastic bottle inside the fiber-based container, which can then perform the corresponding barrier functions. In this case, the fiber-based container merely provides a shell for a thin-walled plastic container. Such a combination is known from WO 2018 / 167192 A1.

[0009] Typically, a fiber-based shell is provided into which a plastic layer or lining is inserted. This is typically done by first providing the fiber-based shell and then inserting a preform into it. Subsequently, this preform is inflated within the fiber-based shell until it touches, or is in contact with, an inner contour of the fiber-based shell. This inflation process typically takes place in a blow mold whose cavity corresponds to the outer contour of the fiber-based shell. As described in WO 2018 / 167192 A1, there is a risk of cracking in the fiber-based container. While this risk has been partially reduced by the teaching in WO 2018 / 167192 A1, the results are still not satisfactory.

[0010] The object of the invention is to overcome at least one or more disadvantages of the prior art. In particular, a device and a method for loading a fiber-based container with a preform, as well as a method for inserting this container into a blow molding tool, are to be provided, which make it possible to reduce the number of defective containers.

[0011] This problem is solved by the devices and methods defined in the independent claims. Further embodiments are described in the dependent claims.

[0012] An inventive method for loading with a preform comprises the following steps: Placing a container on a turntable. Rotating the turntable together with the container into a predetermined position. Inserting a preform into the container.

[0013] As previously explained, fiber-based containers are typically manufactured using a two- or multi-part mold. This results in the containers not being perfectly rotationally symmetrical, but rather exhibiting fine burrs, particularly in the area of ​​the mold parting line(s), which may protrude relative to the rest of the container's surface.

[0014] By rotating the turntable together with the container into a predetermined position, the container can be aligned accordingly. This predetermined position could, for example, be a position that has a specific orientation relative to the orientation of a subsequent blow molding tool into which the fiber-based container is inserted along with the preform. For instance, a protruding burr on the container can be aligned with a parting line of the subsequent blow molding tool.

[0015] The turntable and the container share a common axis of rotation, around which the turntable and container are rotated to position the container. This axis of rotation corresponds to the longitudinal axis of the container. The turntable is a device for holding a single container, allowing each container to be rotated individually.

[0016] Before the preform is placed in the container, it can be heated to an elevated temperature.

[0017] By increasing the temperature of the preform, it can easily be inflated in a later step.

[0018] To insert the preform into the container, the container can be moved vertically into a transfer position.

[0019] Vertical movement can be achieved with simple means, as only linear movement is required. Furthermore, the preform can be held in a corresponding position and does not need to be moved additionally.

[0020] A lifting device may be provided for moving the container, on which the container is held with its base.

[0021] By holding the container at its base, its periphery, including the container body and any adjoining opening, remains unobstructed and visible. The container's rotational position can be easily checked, for example, using optical sensors.

[0022] A lifting device is a simple and cost-effective example of how to achieve vertical movement.

[0023] Preferably, the container is held on the lifting device by a vacuum.

[0024] By holding the container under negative pressure, no additional elements are needed to secure it. Furthermore, pressure points, such as those caused by gripping devices, can be avoided.

[0025] Preferably, the turntable is rotated during the provision of the container until an engagement element of the turntable engages with a corresponding form element of the container.

[0026] A mold element on the container has the same position and / or orientation relative to the mold parting line for every container. Therefore, alignment based on a corresponding mold element results in the mold parting line of the container also being aligned accordingly.

[0027] By rotating the turntable until the engagement element of the turntable engages with the corresponding mold element, the turntable can be positioned in relation to the mold parting line of the container.

[0028] The position of the turntable allows the position of the mold parting line of the container to be determined and adjusted accordingly. By further rotating the turntable, the mold parting line of the container can thus be rotated into a predetermined position.

[0029] In this process, the container is rotated only after the engagement element has entered the forming element. Accordingly, during the rotation of the container, its position relative to the forming element, and thus relative to the turntable, is determined.

[0030] Rotating the turntable also rotates the container.

[0031] Preferably, during the rotation of the container, it is held at its opening by a guide device and is in particular clamped between the guide device and the turntable.

[0032] The guide device prevents the container from tipping over unintentionally. Furthermore, the guide device allows the container opening to be positioned centrally. The vertical movement into a transfer position can then be carried out without further adjustment.

[0033] It may be provided that the preform is placed in a transfer position before being inserted into the container.

[0034] The preform can therefore be held statically in a corresponding position, and only the container needs to be moved relative to the preform.

[0035] After the preform has been inserted, it can be held together with the container using a gripper.

[0036] This allows the preform, along with the container, to be easily moved from the transfer position into a suitable blow mold, into which the preform and container are then placed. After the container and preform are placed in the blow mold, the preform is inflated accordingly.

[0037] The gripper can be a gripper as described in Swiss patent application CH1203 / 20. In particular, it is a gripper that presses an inner wall of the fiber-based container onto an outer surface of the preform.

[0038] The blow molding tool can also be designed in accordance with the aforementioned patent application and have a head plate on which the gripper can rest.

[0039] The gripper and the head plate of the blow molding tool are designed in particular according to the system of gripper and head plate claimed in CH1203 / 20.

[0040] The gripper presses an inner wall of the fiber-based container onto an outer surface of the preform. The outer surface of the preform can be located at its neck, or it can be formed on a section of a protrusion at the neck. This allows the gripper to hold the preform and container combination easily and securely.

[0041] Another aspect of the invention relates to a method for inserting a fiber-based container together with a preform arranged therein into a blow molding tool. The method comprises the following steps: Loading a fiber-based container with a preform using a method as described herein, rotating the container into the predetermined position such that a mold parting line present on the container, leading from the production of the container, is rotated into a position defined relative to the mold parting line of the blow molding tool.

[0042] The position of the parting line of the container corresponds to the position of the parting line of the blow mold, so that any burrs on the container lie in the parting line of the blow mold. This prevents the protruding burrs from resting on a position within the cavity of the blow mold and thus preventing deformation and / or damage to the container.

[0043] It would be conceivable that the blow molding tool has expansions in the area of ​​the mold parting line to accommodate the protruding burrs of the container.

[0044] Alternatively, the blow mold could be designed with flares in a position different from the mold parting line to accommodate the protruding burrs of the container. In this case, the container would be rotated into a predetermined position aligned with these flares, so that when the container is loaded into the blow mold, the protruding burrs would lie against, or within, the corresponding flares.

[0045] Preferably, the container, together with the preform, is placed into a cavity of the blow molding tool from a transfer position using a gripper.

[0046] This ensures that the relative position of the container and the preform in relation to the blow molding tool does not change, or only changes to a predetermined extent.

[0047] The gripper is designed in such a way that, when gripping, it presses an inner wall of the fiber-based container onto an outer surface of the preform, thus holding the preform and container together.

[0048] Another aspect of the invention relates to a device for loading a fiber-based container with a preform in a predetermined position. The device has a rotary table for rotating a container arranged on it into the predetermined position. The rotary table is designed as a device for receiving a single container, so that each individual container can be rotated independently.

[0049] With such a device featuring a turntable, a container can be easily changed in its rotational position.

[0050] The turntable can have at least one engagement element. This element is suitable for engaging with a substantially corresponding form element of the container, so that the container can be rotated with the turntable.

[0051] By engaging a component within the mold element, the container can be rotated together with the turntable. The relative position or orientation of the turntable in relation to the container is maintained. Accordingly, the position of the container can be inferred from the position of the turntable.

[0052] The device may include at least one lifting device with which the container can be moved in a vertical direction.

[0053] This allows the container to be easily moved into a transfer position where a preform can be inserted into the container.

[0054] The lifting device may include a support element onto which the bottom of the container can be placed. The support element is, in particular, essentially complementary to the design of at least a portion of the bottom of the container.

[0055] The support element allows the container to be placed on the lifting device in a reproducible manner. This ensures that all containers on the lifting device are in the same position.

[0056] By essentially creating a complementary design for at least one part of the base, a defined interface can be created between the base of the container and the support element, so that the container can be positioned accurately on the support element.

[0057] The support element can be essentially annular in shape and enclose the turntable. The support element is, in particular, vertically displaceable relative to the turntable.

[0058] The circular shape of the support element allows the turntable to be positioned within it. With this design, the turntable can rotate and twist independently of the support element. The relative displacement of the support element relative to the turntable allows the support element, or any container placed on it, to be lifted off the turntable.

[0059] This allows the container to be easily moved vertically into a transfer position without having to move the turntable. The corresponding mechanisms for moving the turntable can remain stationary.

[0060] The circular shape of the support element allows for the accommodation of a corresponding base of the container regardless of its primary position in relation to its axis of rotation.

[0061] The lifting device may have a device for generating a vacuum, so that a container arranged on the lifting device is held against the lifting device by means of a vacuum.

[0062] The device for generating a vacuum is designed in particular as part of the support element.

[0063] The device for creating a vacuum allows the container to be held without the need for additional holding elements. Furthermore, pressure marks, such as those that can be caused by gripping devices, can be avoided.

[0064] By being designed as an integral part of the support element, the container can be securely held on the support element.

[0065] The device for generating the negative pressure has corresponding openings, particularly in the area of ​​the complementary design of the support element.

[0066] The vacuum can therefore be generated in areas where there are only minor tolerances between the support element and the container. This increases the efficiency of the device for generating the vacuum.

[0067] A guide device on the machine allows the container to be secured against tipping or tilting during the rotation process. It also allows the container, and in particular its opening, to be centered.

[0068] The device can have a gripper to transfer the container together with the preform from a transfer position into a blow molding tool.

[0069] The gripper can be designed in such a way that, when gripping, it presses an inner wall of the fiber-based container onto an outer surface of the preform, thus holding the preform and container together.

[0070] Such a gripper allows the container and the preform to be fixed relative to each other and, in particular, to maintain a position of the container relative to the device and therefore subsequently also relative to the blow molding tool, or, for example, to change it by a predetermined amount.

[0071] The device can also include a first conveyor belt for supplying containers. This allows the containers to be fed evenly and at a consistent position within the device.

[0072] Using schematic figures, different aspects of the invention are described by way of example. It shows: Figure 1: A schematic view of a device for loading a fiber-based container; Figure 2: A first process step shown in a detailed view from the Figure 1Figure 3: a further process step; Figure 4: a further process step; Figures 5A, 5B: a view of a lifting device together with an associated bottom of a container; Figures 6A, 6B: a blow molding tool; Figure 7: a container with a preform in a gripper.

[0073] The Figure 1Figure 1 shows a schematic view of a device 100 for loading a fiber-based container 20. The device 100 has a conveyor belt 101 on which containers 20 are arranged and fed into the conveyor. The device 100 also has a lifting device 50 with a support element 51 attached to it, as well as a rotary table 40. The lifting device 50, and in this case the support element 51, surrounds the rotary table 40 in an annular shape. An engagement element 41 is arranged on the rotary table 40 for engagement with a substantially complementary shaped element 21 located on the bottom 23 of a container 20. For the sake of simplicity, a bottom view of the bottom 23 of the container 20 is shown in the figure 1. Figure 1 shown above turntable 40.

[0074] The containers 20 are moved by the conveyor belt in the direction of arrow P1. The turntable 40 can be rotated about its axis of rotation X, i.e., it is rotatable about its axis of rotation X. This is illustrated by arrow P2.

[0075] To load the lifting device 50, the conveyor belt is moved in the direction of arrow P1, so that a first container 20 is placed on the turntable 40 and accordingly on the support element 51.

[0076] The Figure 2 shows a first procedural step using a detailed view from the Figure 1 Following the placement of the container 20 on the support element 51 (see Fig. 5A A guide device 60 is inserted into the opening 24 of the container 20, and the container 20 is centered with respect to the axis of rotation X. For this purpose, the guide device 60 is moved into the opening 24 of the container 20 in the direction of the rotary table 40.

[0077] The rotary table 40 is then rotated in the direction of arrow P2 until the engagement element 41 is in operative contact with the forming element 21 on the bottom 23 of the container 20. Once this contact is established, the rotary table 40 is moved further until it reaches a predetermined position. This position corresponds to a relative position with respect to a parting line of the blow molding tool (see [reference]). Figure 6 ) into which the container 20 will later be placed. According to the position of the turntable 40, the container 20 also has a specific relative position in relation to the subsequent blow molding tool.

[0078] Once the container 20 is positioned in the predetermined position, a device 90 is used to generate a vacuum (see below). Figure 5 ) activated and thereby the container 20 is held on the support element 51.

[0079] The guide device 60 is then removed from the opening 24 of the container 20, so that this opening 24 is freely accessible.

[0080] The Figure 3 shows a further process step. Following the positioning of container 20, as it is done to Figure 2 As described, a preform 30 is brought into the transfer position shown here above the container 20 using a gripping device 35. As can be seen from the illustration according to the Figure 3 As can be seen, the container 20 and the preform 30 are arranged one above the other in a line along the X axis, so that the preform 30 is centrally located with respect to the opening 24. The gripping device 35 merely holds the preform 30 above a support ring (not specified here), so that the container 20 can be positioned below the support ring on the preform 30.

[0081] The Figure 4Figure 50 shows a further process step after the preform 30 has been placed in the transfer position. In this step, the lifting device 50 was moved vertically upwards so that the container 20 was also in the transfer position. The container 20 was moved vertically over the placed preform 30, so that the preform 30 extended through the opening 24 into the container 20.

[0082] It is evident that the lifting device 50 has been moved in a vertical direction independently of the turntable 40.

[0083] Subsequently, gripper 35 is released and moved away, and the preform is held together with container 20 by another gripper 70, so that the preform 30 together with container 20 can be placed into a suitable blow mold 80. A suitable gripper is required. Figure 7 described.

[0084] The Figures 5A and 5Bshow a view of a lifting device 50 and a turntable 40 ( Figure 5A ) together with an associated base 23 of a container 20 ( Figure 5B The support element 51 is arranged on the lifting device 50. Several openings are visible on the support element 51, which provide part of the device 90 for generating a vacuum. The surface of the support element 51 visible here is essentially complementary to a corresponding surface of the bottom 23 of the container 20. The bottom of the container 23 is in the Figure 5B As can be seen, two mold elements 21 are arranged on the base 23, diametrically opposed to each other with respect to a longitudinal axis of the container. The mold parting line of the container 20 and the associated burrs are not shown in detail.

[0085] The Figures 6A and 6B show a blow molding tool 80 in a top view ( Figure 6A) and in a sectional view along the mold parting line 81, so that only one half of the blow molding tool is visible ( Figure 6B The blow mold 80 has two unspecified blow mold halves which together provide a cavity 82. The mold parting line 81 extends between the two blow mold halves.

[0086] The Figure 7Figure 7 shows a container 20 with a preform 30 in a gripper 70. The gripper 70 transfers the container 20, together with the preform 30, into the blow molding tool 80. The gripper 70 has two legs 71 and 72. Only leg 71 is described below, but the descriptions also apply to leg 72. Leg 71 has a first gripping jaw 73 and a second gripping jaw 74. A gripping surface 731 is arranged on the first gripping jaw 73, and a gripping surface 741 is arranged on the second gripping jaw 74. The gripping surfaces 741 and 731 each extend along an annulus over an angle of 30°. The first gripping jaw 73 is axially spaced from the second gripping jaw 74. In cross-section, the first gripping jaw 73 and the second gripping jaw 74 form a substantially C-shaped cross-section. This C-shaped cross-section is designed to accommodate a corresponding support ring.In relation to the second gripping jaw 74, the first gripping jaw 73 is offset radially outwards.

[0087] In particular, contours can be formed on the gripping surface 731 of the first gripping jaw 73 which improve the friction between this gripping surface 731 and a fiber-based cover 20 to be gripped.

Claims

1. A method for loading a fiber-based container (20) with a preform (30), comprising the steps of: - providing a container (20) on a rotary plate (40) - rotating the rotary plate (40) together with the container (20) into a predetermined position; - inserting a preform (30) into the container (20).

2. The method according to claim 1, characterized in that the preform (30) is heated to a higher temperature before being inserted into the container (20).

3. The method according to either claim 1 or claim 2, characterized in that the container (20) is moved vertically into a transfer position in order to insert the preform (30) into the container (20).

4. The method according to claim 3, characterized in that a lifting device (50) is provided for moving the container (20), on which lifting device the container (20) is held by its base (23).

5. The method according to claim 4, characterized in that the container (20) is held on the lifting device (50) by means of a negative pressure.

6. The method according to any one of claims 1 to 5, characterized in that the rotary plate (40) is rotated when providing the container (20) until an engagement element (41) of the rotary plate (40) engages in a corresponding shaped element (21) of the container (20).

7. The method according to claim 6, characterized in that the container (20) is only rotated after the engagement element (41) is engaged in the shaped element (21).

8. The method according to any one of claims 1 to 7, characterized in that, during the rotational movement of the container (20), said container is held by a guide device (60) at its opening and is clamped in particular between the guide device (60) and the rotary plate (40).

9. The method according to any one of claims 1 to 8, characterized in that the preform (30) is placed in a transfer position before being inserted into the container (20).

10. The method according to any one of claims 1 to 9, characterized in that, after the preform (30) has been inserted into the container (20), the container (20) is held, together with the preform (30), by a gripper (70).

11. A method for inserting a fiber-based container (20) together with a preform (30) arranged therein into a blow mold (80), said method comprising the steps of: - loading a fiber-based container (20) together with a preform (30) by means of a method according to any one of claims 1 to 10, - rotating the container (20) into the predetermined position such that a mold parting plane (22) on the container (20), created by the production of the container (20), is rotated into a position defined relative to the mold parting plane (81) of the blow mold (80).

12. The method according to claim 11, characterized in that the container (20) together with the preform (30) is inserted into a cavity (82) of the blow mold (80) by a gripper (70) from a transfer position.

13. A device (100) for loading a fiber-based container (20) together with a preform (30) in a predetermined position, wherein the device (100) has a rotary plate (40) for rotating a container (20) arranged thereon into the predetermined position, wherein the rotary plate (40) is a device for receiving a single container (20) such that the single container (20) can be individually rotated.

14. The device (100) according to claim 13, characterized in that at least one engagement element (41) is arranged on the rotary plate (40), said engagement element being suitable for engaging in a substantially corresponding shaped element (21) of the container (20) such that the container (20) can be rotated together with the rotary plate (40).

15. The device (100) according to either claim 13 or claim 14, characterized in that the device (100) has at least one lifting device (50) with which the container (20) can be moved in a vertical direction.

16. The device (100) according to claim 15, characterized in that the lifting device has a support element (51) on which a base (23) of the container (20) can be placed, the support element (51) in particular being substantially complementary to a design of at least a portion of the base (23) of the container (20).

17. The device (100) according to claim 16, characterized in that the support element (51) is substantially annular and encloses the rotary plate (40) and, in particular, is vertically displaceable relative to the rotary plate (40).

18. The device (100) according to any one of claims 15 to 17, characterized in that the lifting device (50) has an apparatus (90) for generating a negative pressure such that a container (20) arranged on the lifting device (50) is held on the lifting device (50) by means of negative pressure.

19. The device (100) according to any one of claims 13 to 18, characterized in that the device (100) has a guide device (60) for guiding and supporting the container (20) during rotation.

20. The device (100) according to any one of claims 13 to 19, characterized in that the device (100) has a gripper (70) for inserting the container (20), together with the preform (30), into a blow mold (80) from a transfer position.

21. The device (100) according to any one of claims 13 to 20, characterized in that the device (100) has a first conveyor belt (101) for providing containers (20).