Device and Method for Laminating a Substrate with a Thermoplastic Film

Abstract

The invention relates to an apparatus (1) for laminating a substrate (12) with a thermoplastic film (11), the apparatus (1) comprising the following: —a laminating unit (2) for laminating the substrate (12) with the thermoplastic film (11), —a feed device (4) for the thermoplastic film (11) to the laminating unit (2), wherein the feed device (4) for the thermoplastic film (11) has devices (14) for heating a first side (16) of the film (11) and devices (15) for cooling a second side (17) of the film (11), as well as a number of controllably driven rollers (10) via which the film (11) is guided past the devices (14) for heating and the devices (15) for cooling, wherein a tension of the film (11) can be regulated via the speed of the driven rollers (10).

Claims

1. An apparatus for laminating a substrate to a thermoplastic film, comprising: a laminating unit for laminating the substrate with the thermoplastic film; a feed device for the thermoplastic film to the laminating unit, the feed device for the thermoplastic film including, one or more devices for heating a first side of the film, one or more devices for cooling a second side of the film, a plurality of controllably driven rollers via which the film is guided past the devices for heating and the devices for cooling; wherein a tension of the film can be regulated via the speed of the driven rollers.

2. The apparatus according to claim 1, wherein the driven rollers are arranged, in the direction of movement of the film, at least upstream of and downstream of the devices for heating and for cooling.

3. The apparatus according to claim 1, wherein the thermoplastic film is guided at a distance from the devices for heating.

4. The apparatus according to claim 1, wherein the devices for cooling comprise at least one cooled roller over which the film is guided.

5. The apparatus according to claim 1, wherein the thermoplastic film is guided at a distance from the devices for cooling.

6. The apparatus according to claim 1, wherein, grids are disposed between the devices for heating and the thermoplastic film, the grids being arranged for protecting the devices for heating from contact with the film.

7. The apparatus according to claim 1, wherein the feed device has at least one device for generating an air flow between the thermoplastic film and the devices for heating.

8. The apparatus according to claim 1, wherein the thermoplastic film is guided in the feed device vertically upward and/or downward at least in portions.

9. The apparatus according to claim 1, wherein the thermoplastic film is guided in the feed device obliquely upward and/or downward at least in portions.

10. The apparatus according to claim 1, wherein the thermoplastic film is guided in the feed device around a circular arc at least in portions.

11. The apparatus according to claim 1, wherein the feed device has an alternative feed path for a film which does not comprise any devices for heating or any devices for cooling.

12. The apparatus according to claim 1, further comprising a device for collecting condensate formed at the devices for cooling.

13. A method for laminating a substrate to a thermoplastic film, comprising: providing the substrate; providing the thermoplastic film; providing a laminating unit; feeding the film to the laminating unit, wherein the feeding takes place by means of a plurality of controllably driven rollers via which the film is guided, wherein during feeding the film is heated on a first side and cooled on a second side, and during feeding a tension of the film is regulated via the speed of the driven rollers.

14. The method according to claim 13, comprising one or more devices for heating and one or more devices for blowing air, wherein the film is held at a distance from the devices for heating by an air blown into a space between the film and the devices for heating.

15. The method according to claim 13, comprising the step of collecting a condensate which forms at devices for cooling.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0027] FIG. 1 schematically shows an apparatus for laminating a substrate with a thermoplastic film according to a first embodiment of the invention;

[0028] FIG. 2 schematically shows an apparatus for laminating a substrate with a thermoplastic film according to a second embodiment of the invention;

[0029] FIG. 3 schematically shows an apparatus for laminating a substrate with a thermoplastic film according to a third embodiment of the invention; and

[0030] FIG. 4 schematically shows an apparatus for laminating a substrate with a thermoplastic film according to a fourth embodiment of the invention.

[0031] FIG. 1 shows an apparatus 1 for laminating a substrate with a thermoplastic film. In FIG. 1, the thermoplastic film is denoted by the reference sign 11, the substrate by the reference sign 12 and the already laminated substrate by the reference sign 13.

[0032] The apparatus 1 comprises a laminating unit 2, which in particular has a number of rollers 3 for pressing the film 11 onto the substrate 12. Furthermore, the apparatus 1 comprises a feed device 4 for the thermoplastic film 11 to the laminating unit 2. The film 11 is unwound by an unwinder 5 and transported by means of the feed device 4 to the laminating unit 2, after which the coated substrate 13 is wound by the rewinder 6.

[0033] The feed device 4 has a number of controllably driven rollers 10. In the embodiment shown, three driven rollers 10 are illustrated. However, this illustration is only exemplary and more or fewer driven rollers can also be provided.

[0034] The feed device 4 comprises further rollers or rolls which serve to guide and deflect the film 11 and are only shown by way of example and are not described in more detail. The thermoplastic film 11 is transported by means of the driven rollers 10 in the direction of the arrow 7 (feed direction) to the laminating unit 2. In the embodiment shown, the substrate 12 is transported along the arrow 8 (feed direction) to the laminating unit 2 also by means of a suitable feed device 9. After lamination, the laminated substrate 13 is transported along the arrow 7 to the rewinder 6.

[0035] The film 11 is fed largely contactlessly. Only in the region of the rollers 10 is the film 11 guided or supported at specific points. The film 11 is not supported between the rollers 10. It thus has a tension caused in particular by the gravity acting thereon and by the rotational speeds of the rollers 10.

[0036] Along its path through the feed device 4, the thermoplastic film 11 is guided between the rollers 10 past devices 14 for heating a first side 16 of the film 11 and devices 15 for cooling a second side 17 of the film 11. The devices 14 for heating and the devices 15 for cooling are also shown here merely by way of example. The number and arrangement of the devices 14 for heating and the devices 15 for cooling can vary.

[0037] Heating the first side 16 causes softening to partial melting of the thermoplastic film 11 on its first side 16, such that said film can bond to the substrate in the laminating unit 2. Cooling the second side 17 serves to prevent the film 11 from melting completely and to maintain a certain stability, which is necessary for the transport process to the laminating unit 2.

[0038] The film 11 is guided away from the devices 14 for heating and the devices 15 for cooling. Grids 18 are arranged between the devices for heating 14 and the film 11, which are intended to prevent the film 11 from adhering to the devices 14 for heating.

[0039] The feed device 4 has an alternative feed path for a film to the laminating unit 2, which is indicated in FIG. 1 by a dashed line 19 and which is not guided past the devices 14 for heating and devices 15 for cooling. The alternative path can be used for a film which does not consist of a thermoplastic material or which is not to be heated or cooled for other reasons.

[0040] The apparatus 1 further comprises a trough 20 for collecting condensate which is formed on the devices 15 for cooling due to the moist ambient air. The trough 20 is arranged below the devices 15 for cooling, such that condensate flows off the devices 15 for cooling due to gravity and drips into the trough 20. On this path, the condensate does not pass through any further elements of the feed device 4, in particular not the devices 14 for heating, which could be damaged by the condensate. The trough 20 is thus positioned in such a way that condensate forming on the devices 15 can drip directly into the trough 20. Discharging the condensate ensures that no condensate comes into contact with the film 11, which could reduce the quality of the surface.

[0041] FIG. 2 shows a second embodiment of an apparatus 1 for laminating a substrate with a thermoplastic film. This apparatus 1 differs from the embodiment shown in FIG. 1 in that several driven rollers 10 are provided which guide the film 11 on a semi-circular path.

[0042] FIG. 3 shows a third embodiment of the apparatus 1 for laminating a substrate with a thermoplastic film 11. This embodiment differs from those previously shown in that several driven rollers 10 are arranged one above the other such that the film 11 is guided vertically in portions. In the embodiment shown, two devices 14 for heating and two devices 15 for cooling are also arranged one above the other in each case.

[0043] This arrangement is particularly space-saving and can also be implemented in a small installation space. The devices 15 for cooling are arranged one above the other in this embodiment, but not above devices 14 for heating, so that no condensate can drip onto the devices 14 for heating. A trough 20 for collecting condensate is again provided immediately below the lower device 15 for cooling.

[0044] FIG. 4 shows a fourth embodiment of the apparatus 1 for laminating a substrate 12 with a thermoplastic film 11. This embodiment differs from those previously shown in that the film 11 is guided in portions in the feed device 4 not in a contactless manner, but by means of a cooled roller 21. The second side 17 of the film 11 thus rests, in places, on the surface of the cooled roller 21. The speed of the cooled roller 21 can also be controllably driven.

[0045] However, the film is guided in a contactless manner on the route portion between the first driven roller 10 and the cooled roller 21. The roller 10 has the task of compensating for stresses arising from the heating in the film 11.

[0046] In this embodiment, scrapers 22 are provided which scrape condensate produced on the cooled roller 21 from the roller 21 and let it drip into the trough 20. In this case, the scrapers 22 are arranged in the region of a lower side 23 of the roller 21, while the film 11 is guided on the upper side 24 of the roller 21. In this way, the film 11 is prevented from coming into contact with condensate on the surface of the roller 21, which could reduce the quality of the film surface.

LIST OF REFERENCE SIGNS

[0047] 1 Apparatus [0048] 2 Laminating unit [0049] 3 Roller [0050] 4 Feed device [0051] 5 Unwinder [0052] 6 Rewinder [0053] 7 Arrow [0054] 8 Arrow [0055] 9 Feed device [0056] 10 Roller [0057] 11 Film [0058] 12 Substrate [0059] 13 Laminated substrate [0060] 14 Device for heating [0061] 15 Device for cooling [0062] 16 First side [0063] 17 Second side [0064] 18 Grid [0065] 19 Dashed line [0066] 20 Trough [0067] 21 Roller [0068] 22 Scraper [0069] 23 Lower side [0070] 24 Upper side