EP4330009A1

EP4330009A1 - Device and method for a membrane laminating process with a bent-back section in a method step

Info

Publication number: EP4330009A1
Application number: EP22725871.2A
Authority: EP
Inventors: Florian WÜSTHOLZ; Frank WÜSTHOLZ
Original assignee: W Tip & Co Kg GmbH
Current assignee: W Tip & Co Kg GmbH
Priority date: 2021-04-28
Filing date: 2022-04-27
Publication date: 2024-03-06
Also published as: DE102021110910A1; WO2022229261A1; CN117203037A

Abstract

The invention relates to a method and a manufacturing device (1) for laminating a top material (2) onto a component (B) with a top material (2) section which is bent back about at least one component edge (K) of the component (B). The manufacturing device has the following: a component receiving area (20) for receiving the component (B) on a support face (21) of the component receiving area (20), said component receiving area (20) being provided with a plurality of air passage openings (22) or vacuum openings in order to suction air from a region (23) above the support face (21) to a suction region (24) facing away from the support face (21) through the air passage openings (22) or vacuum openings using a suction device (A); and a thin flexible film (F) for applying onto a surface (S) of a top material (2) applied onto a component, in particular the surface which forms the subsequently visible face of the top material on the component (B), wherein the film (F) is preferably flexible such that the film sealingly lies against the surface of the top material (2) by generating a negative pressure using a suction device (A) in the region (23) and such that the film additionally sealingly lies against the top material (2) at least on a section of the top material (2) on the component (B), said section being bent back about a component edge.

Description

Device and method for membrane lamination with folding in one

process step

Description:

The invention relates to a device and a method for membrane lamination with folding in one method step.

Improved laminating processes are used in particular in vehicle construction. The focus is on productivity, costs and manufacturing technology. A laminating process is z. B. leather lamination. High-quality vehicle interiors impress with their design and first-class materials. Textile and leather interiors are no longer reserved exclusively for the premium segment, but are increasingly being used in larger numbers in vehicles in the mid-range price segment. Therefore, it is desirable to find automated processes with which such materials, textiles, leather, fabrics and the like (hereinafter generally referred to as outer fabric) can be applied to a base body or carrier.

There are a variety of applications where an upper made of leather, imitation leather, fabric, foil or other materials

Substrate surfaces are firmly bonded and a fold must also be made.

A common method is the membrane lamination process, in which a vacuum is created under a pressure-closing medium (membrane) and the outer fabric is thus pressed firmly onto the substrate. The negative pressure is maintained until the adhesive between the substrate and the upper fabric has hardened and the laminated component can be removed. A temperature-activatable adhesive is often used here.

Today's membrane lamination processes have the disadvantage that the pressure generated by the vacuum only acts on the front side of the components and therefore a folded area cannot be subjected to pressure. In other words, a folding cannot be produced in one work step with the known methods. Folded areas then have to be produced in a downstream process.

The term "fold over" refers to an area in which the outer fabric is wrapped around an edge of the carrier and glued to the back of the edge.

Another disadvantage of known membrane lamination processes is that due to the very stiff membrane, only relatively flat components are suitable for this membrane lamination. In the case of components with complex three-dimensional shapes, the membrane cannot follow the contour of the component, so that in these areas no contact pressure is applied is sufficient.

Another disadvantage results from the fact that in classic membrane lamination systems, the membrane is firmly clamped in a so-called clamping frame, which in turn is mounted on a lowering device. After the membrane has been lowered onto the component and the negative pressure has been applied, it is no longer possible to check the correct positioning of the upper fabric on the substrate.

Leather in particular as a natural material, but also other upper goods materials, place very high demands on processing. In order to process sensitive materials such as real leather in a highly productive manner and with reproducible quality, the individual processes of surface treatment, adhesive application and the actual lamination must be precisely coordinated. This is often done in a laborious manual activity, especially for a folding.

Variant diversity, quality requirements, quantities and a large number of project-specific influencing parameters require improved production solutions that can only be implemented with extensive experience and well-founded technological and process know-how. This brings high effort and high

costs with it.

Thus, although the laminating tools mentioned are available in the prior art, they have the disadvantages already explained. Although these are technically mature and tried and tested in practice, they require high tool costs and do not allow folding in a single process step. Overall, the devices known in the state of the art and the methods as a whole are not capable of producing a fold during lamination, in particular in a single method step. The object of the invention is therefore to overcome the aforementioned disadvantages and to provide an improved device and a corresponding method for lamination with a fold. This should go hand in hand with a high level of flexibility, ie the possibility of using components with complex shapes or vehicle parts on the same laminating line, in order to achieve lower production costs, improved quality management and batch-specific production as well as risk minimization. This object is achieved by the combination of features according to claim 1.

According to the invention, a production device is provided for this purpose in which an upper fabric is applied to the component between a component arranged on a component carrier and a film that can be subjected to negative pressure from the inside and then an adhesive provided between the component and the upper fabric is activated.

The present invention obviates the aforementioned difficulties by using a thin and flexible film as the environmental pressure isolating medium. In conjunction with the corresponding design of the workpiece carrier, a sufficiently thin and flexible film can also enclose the folded areas on the back of the component so tightly that the negative pressure, i.e. the contact pressure, is sufficient for lamination.

In addition, the use of a thin film has other advantages. The foil is "free" in its movement, so that enough foil material can be fed in to tightly enclose the areas around and below the component. For this purpose, the film can loosely in a corresponding The frame can be introduced and the frame with the film is guided over the component so that the film initially lays roughly over the component. Due to the flexible and trackable foil areas, when applying a sufficient negative pressure from the component side, the foil can be applied around the component on its surface like a "calm". Instead of the film, a pressure-sealing flat element, in particular an elastically stretchable element, can also be used.

Alternatively, the film can also be used without a frame and simply laid loosely over the component.

A correspondingly designed device also enables the area of the component to be viewed after the negative pressure has been applied. This can be improved by making the film transparent. In this way, a targeted control of the process is possible, in particular the control of whether the outer fabric to be applied to a component is positioned correctly and without creases and is in contact before the actual connection process in the laminating process is initiated with the activation of the adhesive.

If a particularly complex geometry of the component prevents the film from lying tightly enough like a flat surface on the component surface in certain areas, so-called inserts can be attached to the component before the vacuum is applied in a preferred embodiment of the invention , ensure a targeted pressure distribution in these areas as well.

A further alternative embodiment of the invention provides for pressure differential lamination. This means that between the inside of the foil on the component and the outside of the foil (ie the turned outside outside and above the film, a pressure difference is generated, preferably by additional application of overpressure from the outside, in addition to the negative pressure from the component side, ie from the inside. Through the targeted combination of negative and positive pressure, highly complex components can be reliably laminated with an outer fabric, even in the folded area and in the complex surface shapes.

A further aspect of the present invention relates not only to the device for laminating but also to a method which is defined as follows: a. Placing the workpiece to be laminated or a component to be laminated on a workpiece carrier; b. Suction of existing air (gas) by means of a suction device through holes made in the component as intended and through vacuum openings in the workpiece carrier; c. Placing an upper fabric on the component and preferably fixing the upper fabric by moving mechanically actuated fixing devices into their fixing position, which are provided for fixing the upper fabric in an intended position; i.e. Fixing the upper fabric by generating a negative pressure on the side of the upper fabric facing the component opposite the visible side of the upper fabric, preferably as a result of the suction of the air in this area; e. Preferably removing the fixing devices from their fixing position so that the surface of the upper fabric is free of the mechanically operable fixing devices; f. application of an airtight thin film to the outer fabric; G. Generating a negative pressure underneath the foil in the area facing the component in such a way that the foil lies tightly against the outer surface of the outer fabric and in particular also around individual or several or all component edges of the component around; H. Activation of a heat-activatable adhesive applied to the application side of the outer fabric by increasing the temperature to at least the activation temperature.

According to a preferred embodiment of the invention, any or all of the following additional steps may be performed.

Optionally, quality control can be carried out to ensure that the outer fabric is correctly seated on the component, either based on the surface contour and freedom from creases and/or due to the sufficient optical transparency of the film in such a way that features (such as the freedom from creases, the position , fold areas, etc.) of the applied outer fabric are recognizable before the adhesive is activated and can be corrected if necessary.

In a further advantageous embodiment of the invention, it can be provided that after step g) above, a cover or a bell is moved over the workpiece, so that the workpiece is enclosed (preferably sufficiently tightly closed that the

Leak rate is lower than the inflow quantity per same unit of time of a medium for generating an overpressure) and then an overpressure in the bell is achieved by means of a pressure generating device. Flier causes an additional contact pressure on the film and thus the upper surface from the outside.

A further optional aspect of the present invention accordingly also relates to a component B which, compared to a conventional component of the same shape, is additionally designed with a large number of air passage openings and vacuum channels. It is also advantageous if, in principle, a pressure differential method is used, with the pressure on both sides of the film deviating significantly from the ambient pressure in the area surrounding the device. At least by definition, the surrounding area is considered to be a distance of about 5-15 meters from the laminating device in order to determine a reference value for the atmospheric pressure if necessary.

It is also advantageous if the adhesive is activated by increasing the temperature as a result of a stream of warm air, preferably by warm air flowing through the bell or cover. In addition or as an alternative, the workpiece carrier can be heated, an infrared radiator can be used in the bell, or a combination of these can be used. In a further preferred embodiment of the invention, it can optionally be provided that the component is cooled when the adhesive reacts.

When using a bell, the excess pressure in the bell is first removed, then the bell is opened or removed, then the negative pressure below the film is switched off, the film is removed and finally the component with the laminated outer fabric is removed .

The advantage over pure infrared heating is that the heat can be reached more quickly and easily when heating up, and the more even and better controllable introduction of heat. It is advantageous if the heat-carrying medium (e.g. heated air) is specifically temperature-controlled and flows through the enclosed space below the bell. Further advantageous configurations of the device according to the invention are:

- A hot air supply and a hot air discharge lead into the interior of the component holder in order to supply or remove hot air from a waste heat device of the transport system,

- one or more air turbulence devices are provided in the interior of the component holder,

- the heat required for activation is used as waste heat from an external unit,

- The component carrier is replaceable on a base plate or work tool carrier plate attached to a movable transport system.

Other advantageous developments of the invention are characterized in the subclaims or are described in more detail below together with the description of the preferred embodiment of the invention with reference to the figures.

Show it:

1 shows an exemplary illustration of a production device according to the invention;

Fig. 2 shows an alternative embodiment similar to Figure 1 but with

depositor E and

Fig. 3 is an alternative view of an embodiment of a

Outer goods laminating device together with a bell.

The invention is explained in more detail below with reference to FIGS. 1 to 3, with the same reference numbers in the figures indicating the same structural and/or functional features. The figures show an exemplary representation of a production facility 1 according to the invention. FIG. The production device 1 is designed for laminating an upper fabric 2 onto a component B with a folding in one process step.

That means a lamination of an upper fabric 2, such. B. Leather on a component B with folding of the outer fabric 2 around at least one, preferably all component edges K of the component B around. Furthermore, the manufacturing facility 1 has a component receptacle 20 for receiving the component B. A surface shape that reproduces the shape of the building part B at least in sections is preferred. However, different shapes of the component holder 20 are also conceivable.

The component holder 20 has a support side 21 on which a component B to be laminated with an upper fabric 2 is applied. The component holder 20 is provided with a plurality of air passage openings 22 (also called vacuum openings) in the support area in order to suck air from an area 23 above said support side 21 by means of a suction device A and to generate a negative pressure there. The sucked-off air is sucked through the air passage openings 22 to a suction area 24 which is remote from the support side 21 . By sucking in the air, the upper fabric 2 can be pulled onto the component and fixed there.

Furthermore, a thin, flexible film F is provided for application to the surface side S of an upper fabric 2 applied to the component B, in particular to that surface side which forms the later visible side of the upper fabric 2 on the component B. Conceptually it is provided that the Foil F is preferably flexible enough that it lies tightly against the surface of the upper fabric 2 in area 23 by generating a negative pressure by means of a suction device A and also tightly against the upper fabric 2 at least at a fold of the upper fabric 2 on the component B around a component edge applied. The use of the film is explained in more detail in the process sequence described below.

In any case, the properties of the film must be determined in such a way that the film is sufficiently thin and wraps around the surface of the component to be laminated like a skin when a vacuum is generated. Since a combination of the selected film materials, the material thickness as such, the flexibility and the elasticity must be adapted to the respective application, it is not possible to determine fundamentally fixed properties of the film. If a component z. B. formed less complex, a certain coefficient of elasticity and a certain flexibility with a selected film thickness is sufficient to apply the set process pressure or negative pressure like a skin around the component geometry. In any case, it makes sense to have elasticity in the direction of the film surface that allows stretching in this direction of about 5%, preferably 10%, based on the initial dimensions of the film used. The thickness of the film is in the range of less than 1 mm, preferably in the range ??? (An example value would be useful here)

It is conceivable that the film F is held in a holding frame (not shown in detail), the holding frame being movable together with the film F in such a way that it can be guided over the component carrier or the component B.

Furthermore, to fix the upper fabric 2 on the component carrier, mechanically actuatable fixing devices 3 can be provided, which are guided by a fi xierposition can be actuated into a release position and vice versa and one or more of the fixing devices 3 preferably simultaneously determine reference positions for the application of the upper fabric 2. Such fixing devices 3 are only indicated in FIG. 2 as an example. The specific configuration depends on the respective individual component geometry.

According to FIG. 2, the system according to the invention can also include one or more three-dimensionally shaped inserts E, which can be inserted between the film F and the visible side S of the upper fabric 2, as shown in FIG. Indentations, bulges or undercuts in the surface area of a building part B are carried over to the upper fabric 2 in an optimized manner via the film in this area. For this purpose, the inserts E preferably have at least one surface which has a shape corresponding to the shape of the component in the area in which the insert E is inserted. However, other geometries that are specially adapted to the respective application are also conceivable.

Furthermore, a groove 22 can be provided, in which a seam fold of the upper fabric 2 can be embedded. FIG. 3 shows an alternative manufacturing device 1, in which a bell 40 is additionally provided, which is designed to be slipped or guided over the component carrier 20 in order to form a housing for it. The housing is preferably designed to be tight on the bearing surfaces. A warm air supply duct 41 can be provided on the bell 40 in order to convey warm air into the interior 43 of the bell 40 for adhesive activation when the bell 40, as shown schematically in FIG. 3, is used as a housing for the component carrier 20.

It is also possible and preferred if a warm air discharge channel 42 is also provided on the bell 40 in order to remove the warm air from the interior to carry space 43 out of the bell 40 when the bell 40 is used as a housing solution for the component carrier 20 . A further aspect of the present invention relates not only to the device but also to the method for laminating. The method is not explained in a restrictive manner, but is explained by way of example with reference to the device 1 in FIG. a. First, the component B to be laminated is placed on the workpiece carrier 20; b. The air (gas) that is present is then sucked in by means of a suction device A through holes 22 in the workpiece carrier 22 made in the component as intended; c. Placing an upper fabric on the component and preferably fixing the upper fabric by moving mechanically actuated fixing devices into their fixing position, which are provided for fixing the upper fabric in an intended position; i.e. Fixing the upper fabric by generating a negative pressure on the side of the upper fabric facing the component opposite the visible side of the upper fabric, preferably as a result of the suction of the air in this area; e. Preferably removing the fixing devices from their fixing position so that the surface of the upper fabric is free of the mechanically operable fixing devices; f. application of an airtight thin film to the outer fabric; G. Generating a negative pressure underneath the film in the area facing the component in such a way that the film lies tightly against the outer surface of the outer fabric and in particular also around individual, several or all component edges of the component; H. Activation of a heat-activatable adhesive applied to the application side of the outer fabric by increasing the temperature to at least the activation temperature.

In an advantageous embodiment of the method mentioned, steps d) to f) are maintained until the adhesive between the component B and the outer fabric OB is activated or its activation temperature is reached.

The implementation of the invention is not limited to the preferred exemplary embodiments specified above. Rather, a number of variants are conceivable which make use of the solution shown even in the case of fundamentally different designs.

For example, B. Figures 4 and 5 on the following facts. The disadvantage of the film is that it tends to become firmly attached to the component holder when the vacuum is applied before it can attach itself firmly to the fold areas. However, it must be ensured that the foil slides or can be moved over the component holder even when the vacuum is applied, in order to feed sufficient foil material into the fold area. For this purpose, an air-permeable but pressure-resistant material is attached to the surface in the area of the component holder in question. This material can be, for example, an open-pore foam or a knitted spacer. The effect of this arrangement is that the air can flow under the film and the film is prevented from being sucked in. As an alternative to an air-permeable material, the component holder can contain ventilation holes that are subjected to the ambient pressure.

According to the invention, the subject matter of one of the claims or as described above can be further developed by the following features: Air-permeable material (Fig. 4) or ventilation holes (Fig. 5) to prevent the foil from being sucked in.

For example, B. Figures 6 and 7 in an alternative solution to Figure 2 on the following facts. In general, it can be stated that the film does not always completely follow the complex geometries of the component or the component holder and therefore does not enclose the outer fabric in all areas and press against the component.

As a solution, the invention provides, instead of just filling out cavities, as shown in FIG. 2, to expand the insert as a molded body in order to also enclose areas of the component that are limited on two sides or that are concave. This makes it easier to guide the film and pressure can be directed to the desired areas. In this embodiment, the film does not have to fit snugly everywhere, it is sufficient to exert sufficient pressure on the shaped body. According to the invention, the subject matter of one of the claims or as described above can be further developed by the following features: The insert can also be a shaped body that in addition to 3-sided (FIG. 2), 2-sided (FIG. 6) or straight surfaces of the component can also enclose concave (FIG. 7) surfaces in order to selectively exert the pressure required for lamination. The shaped body can be rigid or elastic (e.g. silicone).

Furthermore, Figures 8 and 9 relate to the following inventive fact. The heating of the component and the upper fabric to the activation temperature by means of infrared radiators requires direct irradiation of the surface. The heating up to the back to z. B. to bring the folded areas to activation temperature, takes a comparatively long time. The use of electromagnetic radiation below the infrared spectrum (e.g. microwaves) can help here, since microwaves penetrate deeper into the penetrate the component and thus heat the back of a substrate and thus the fold area to the required temperature in a shorter time.

Claims

patent claims

1. Production device (1) for laminating an upper fabric (2) onto a component (B) with folding of the upper fabric (2) around preferably at least one component edge (K) of the component (B), the production device having the following: a. a component holder (20) for receiving the component (B) on a support side (21) of the component holder (20), the component holder (20) being provided with a plurality of air passage openings (22) or vacuum openings in order to be able to use a suction device (A) suck air or a gas from a region (23) above the support side (21) to a suction region (24) facing away from the support side (21) through the air passage openings (22) or vacuum openings; b. a thin, flexible foil or pressure-sealing sheet

Element (F) for application to a surface side (S) of an upper fabric (2) applied to a component, in particular to that surface side which forms the later visible side of the upper fabric on the component (B), the film (F) preferably is so flexible that by generating a

vacuum by means of a suction device (A) in the region (23) on the surface of the upper fabric (2) and preferably also at least on a fold of the upper fabric (2) on the component (B) around a component edge around the upper fabric ( 2) tight fitting.

2. Manufacturing device (1) according to claim 1, characterized in that three-dimensionally shaped inserts (E) are also provided, which can be introduced between the film (F) and the visible side (S) of the upper fabric (2), wherein the Inserts (E) preferably have at least one surface which has a shape corresponding to the shape of the component in the area in which the insert is inserted. 3. Manufacturing device (1) according to claim 1 or 2, characterized in that a bell (40) is also provided, which is designed to be guided over the component carrier in order to form a housing for this. 4. Production device (1) according to one of the preceding claims, characterized in that an infrared radiator (with or without a bell) is provided in order to heat the component and/or the upper fabric.

5. Production device (1) according to claim 3, characterized in that a warm air supply channel (41) is provided on the bell (40) in order to convey warm air into the interior (43) of the bell (40) for adhesive activation when the Bell (40) is used as a housing for the component carrier (20).

6. Production device (1) according to claim 4, characterized in that a warm air discharge channel (42) is provided on the bell (40) in order to convey warm air out of the interior (43) of the bell (40) when the bell (40 ) is used as a housing for the component carrier (20).

7. Manufacturing device (1) according to any one of the preceding claims, characterized in that the film (F) in one Holding frame is preferably kept relaxed, the holding frame being movable together with the film (F) so that it can be guided over the component carrier. 8. Production device (1) according to one of the preceding claims, characterized in that mechanically actuatable fixing devices (3) are provided for fixing the upper fabric (2) on the component carrier, which can be actuated from a fixing position to a release position and vice versa and a or several of the fixing devices (3) preferably simultaneously determine reference positions for the application of the upper fabric (2).

9. A method for laminating an upper fabric (2) onto a component (B) with folding the upper fabric (2) around at least one component edge (K) of the component (B), preferably with a production device according to one of claims 1 to 8, with the following steps: a. Placing the component to be laminated (B) on a workpiece carrier (20); b. Sucking in air (gas) by means of a suction device (A) through vacuum openings (22) or air passage openings made in the workpiece carrier (20) as intended; c. Placing an upper fabric (2) on or over the component (B); i.e. Fixing the upper fabric (2); e. application of an airtight thin film or a pressure-tight flat element (F) to the outer fabric (2); f. Generation of a negative pressure in such a way that the film (F) or the pressure-sealing flat element (F) lies tightly against the outer surface of the top fabric (2) and in particular also around individual, several or all component edges (K) of the component (B); G. optional activation of a heat-activatable adhesive applied to the application side of the outer fabric (2) by increasing the temperature to at least the activation temperature. 10.A method according to claim 8, characterized in that the upper fabric (2) is fixed to fixing devices.

11. The method according to claim 8 or 9, characterized in that a cover or a bell (G) is additionally moved over the component (B), so that the component (B) is housed and in the bell (G) to increase the temperature of the upper fabric (2), a warm medium is introduced and the temperature is increased at least up to the activation temperature of the adhesive used to bond the upper fabric (2) to the component (B).