METHOD AND DEVICE FOR CONNECTING FIBRE-REINFORCED WEBS

Abstract

Method and device for connecting two webs (1), reinforced with unidirectionally oriented continuous fibres, by ultrasonic welding, wherein the fibres are embedded in a matrix of polycarbonate and the webs have abutting edges that are substantially square and substantially flat, characterized by the following steps:arranging the webs abutting one another in the region of the abutting edges in a welding device between a sonotrode (2) and an anvil (3),welding the webs by means of ultrasound, wherein the sonotrode and the anvil exert pressure on the webs to be welded in the melting region between the webs and perpendicularly to the abutting edges of the webs,removing the welded-together webs (4) from the welding device.

Claims

1. A process for joining two sheeting articles reinforced with unidirectionally aligned endless fibres by ultrasonic welding, wherein the fibres are embedded in a matrix of polycarbonate and the sheeting articles have abutting ends that are substantially rectangular and substantially even, the process comprising: (1) arranging the sheeting articles next to one another end-to-end in the region of the abutting ends in a welding apparatus between a sonotrode and an anvil, (2) welding the sheeting articles by means of ultrasound, wherein the sonotrode and the anvil exert pressure on the to-be-welded sheeting articles in the melting region between the sheeting articles and perpendicularly to the abutting ends of the sheeting articles, (3) removing the sheeting articles that are welded to one another from the welding apparatus.

2. The process according to claim 1, wherein the sheeting articles that have been welded to one another are locally fixed in their shape by a following press roll.

3. The process according to claim 1, wherein the fibres employed are natural fibres or man-made fibres or a mixture of both.

4. The process according to claim 3, wherein the natural fibres are fibrous mineral or vegetable fibres and that the man-made fibres are inorganic synthetic fibres or organic synthetic fibres.

5. The process according to claim 1, wherein the volume content of the fibres in the sheeting articles is respectively from 20 to 80 vol %.

6. The process according to claim 1, wherein the regions of the sheeting articles that are welded to one another have a lower content of fibres than the remaining regions of the sheeting articles, wherein the regions of the sheeting articles that are welded to one another have one half or less of the fibre content of the remaining regions of the sheeting articles and the regions of the sheeting articles that are welded to one another are in the region of the abutting ends and are 0.1 mm to 3 mm deep measured perpendicularly to the abutting end inwards into the sheeting article.

7. A sheeting article produced by a process according to claim 1, wherein the thickness of the sheeting article at the weld join deviates from the thickness of the sheeting article outside the weld join by not more than 20%.

8. An apparatus for performing the process according to claim 1, wherein the apparatus comprises the following components: (A) a feeding device, (B) a sonotrode, (C) an anvil,

9. The apparatus according to claim 8, wherein the sonotrode is a roller seam sonotrode.

10. The apparatus according to claim 8, wherein the anvil is an anvil wheel or an anvil roll.

11. The apparatus according to claim 8, wherein the apparatus comprises two.

12. The apparatus according to claim 11, wherein the sonotrodes are arranged one after another in their rolling direction.

13. The apparatus according to claim 8, wherein the apparatus comprises a following press roll.

14. A sheeting article reinforced with unidirectionally aligned endless fibres which comprises a matrix of polycarbonate and which comprises at least one region as a melting region which has a lower content of fibres than the remaining regions of the sheeting article, wherein the content of fibres in the melting region is one half or less of the fibre content of the remaining regions of the sheeting article, wherein the melting regions are in the region of the abutting ends and are 0.1 mm to 3 mm deep measured perpendicularly to the abutting end inwards into the sheeting article.

15. A method comprising, producing fibre-reinforced final sheetings by ultrasonic welding utilizing the sheeting article according to claim 14 in the configuration of a sheeting piece.

16. A multilayer composite constructed from two or more sheeting articles according to claim 7.

Description

[0109] Preferred embodiments of the invention are depicted by the following figures without the invention being limited to these embodiments thereby.

[0110] FIG. 1: shows a plan view of the apparatus for performing the process according to the invention for joining two fibre-reinforced sheeting articles by ultrasonic welding with only one sonotrode where the reference numerals have the following meanings: [0111] 1 sheeting section [0112] 2 roller seam sonotrode [0113] 3 press roll [0114] 4 final semifinished sheeting [0115] 5 weld join [0116] 6 advancement direction of sheeting article and of the final semifinished sheeting [0117] 7 operating direction of roller seam sonotrode and of press roll during ultrasonic welding procedure

[0118] FIG. 2: shows a plan view of the apparatus for performing the process according to the invention for joining two fibre-reinforced sheeting articles by ultrasonic welding with two sonotrodes where the reference numerals have the following meanings: [0119] 1 sheeting section [0120] 2 roller seam sonotrodes [0121] 3 press rolls [0122] 4 final semifinished sheeting [0123] 5 weld join [0124] 6 advancement direction of sheeting article and of the final semifinished sheeting [0125] 7 operating direction of roller seam sonotrodes and of press roll during ultrasonic welding procedure

[0126] FIG. 3: shows a side view of the apparatus for performing the process according to the invention for joining two fibre-reinforced sheeting articles by ultrasonic welding where the reference numerals have the following meanings: [0127] 1 sheeting section [0128] 2 roller seam sonotrode [0129] 3 anvil roll [0130] 4 final semifinished sheeting [0131] 5 melting region of the sheeting section [0132] 6 melting region of the final semifinished sheeting

[0133] FIG. 4 shows a brightfield reflected light micrograph of a section through a fibre-reinforced semifinished sheeting in the region of the weld join, wherein the thickness was measured as 186 m.

[0134] FIG. 5 shows a brightfield reflected light micrograph of a section through the same fibre-reinforced semifinished sheeting as in FIG. 5, but outside the region of the weld join, wherein the thickness of the semifinished sheeting was measured as 204 m.