Edge protector for a papermachine clothing

Abstract

A method for producing an edge protector on a clothing for a machine producing or finishing a fibrous, paper, cardboard or tissue web, includes providing a clothing formed substantially from a woven fabric with crossing weft and warp threads and opposite side edges, applying a film strip onto a surface of one side edge and, immediately before bringing the film strip into contact with the clothing, surfaces of the film strip and the clothing facing each other are heated to slightly melt the surfaces. A pressing force exerted on the film strip applied to the surface of one of the side edges, results in the film strip penetrating at least partially into the woven fabric. That side edge of the clothing with the film strip is cooled, resulting in a stable, particularly integrally joined and form-locking connection between the film strip and the side edge of the clothing.

Claims

1. A method for producing an edge protector on a clothing for a machine for producing or finishing a fibrous, paper, board or tissue web, the method comprising: providing the clothing to be provided with the edge protector, the clothing being substantially formed from a woven material with crossing weft threads and warp threads and two side edges lying opposite one another; applying a film strip to a surface of one of the two side edges of the clothing by heating a surface of the film strip facing the clothing and a surface of the clothing facing the film strip, immediately before bringing the film strip into contact with the clothing, to slightly melt the surface of the film strip and the surface of the clothing; exerting a pressing force on the film strip applied to the surface of one of the two side edges of the clothing, causing the film strip to penetrate at least partially into the woven material; and cooling the side edge of the clothing provided with the film strip, forming a stable connection between the film strip and the side edge of the clothing.

2. The method according to claim 1, which further comprises forming the connection between the film strip and the side edge of the clothing to be integral and form-locking.

3. The method according to claim 1, which further comprises trimming the side edge provided with the film strip.

4. The method according to claim 1, which further comprises also providing a second side edge of the two side edges of the clothing with an edge protector by carrying out the applying, exerting and cooling steps.

5. The method according to claim 1, which further comprises forming the clothing and the film strip from substantially identical basic materials.

6. The method according to claim 1, which further comprises forming the film strip at least predominantly from PET.

7. The method according to claim 1, which further comprises providing the film strip with at least one of a width between 20 mm and 50 mm or a thickness between 50 μm and 400 μm.

8. The method according to claim 1, which further comprises providing the film strip with at least one of a width between 30 mm and 40 mm or a thickness between 100 μm and 350 μm.

9. The method according to claim 1, which further comprises using a jet of hot air to carry out the step of heating the surface of the film strip facing the clothing and the surface of the clothing facing the film strip.

10. The method according to claim 9, which further comprises directing the jet of hot air into an inlet gap formed between the film strip and the clothing.

11. The method according to claim 1, which further comprises using a heating wedge to carry out the step of heating the surface of the film strip facing the clothing and the surface of the clothing facing the film strip.

12. The method according to claim 1, which further comprises carrying out the step of exerting the pressing force onto the film strip applied to the surface of one of the two side edges of the clothing by using a pressure roll and a further roll or a substantially flat plate as an opposing element to the pressure roll.

13. The method according to claim 1, which further comprises carrying out the step of exerting the pressing force onto the film strip applied to the surface of one of the two side edges of the clothing by using two pressure plates tapering toward one another in a wedge shape and guiding the clothing together with the film strip through a tapering gap between the two pressure plates.

14. A clothing, comprising an edge protector produced according to claim 1.

15. The clothing according to claim 14, wherein the clothing is a dryer fabric.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

(1) FIG. 1 shows a first exemplary embodiment of the method according to the invention,

(2) FIG. 2 shows a second exemplary embodiment of the method according to the invention,

(3) FIG. 3 shows a third exemplary embodiment of the method according to the invention, and

(4) FIG. 4 shows a view from above of the clothing provided with an edge protector.

DETAILED DESCRIPTION OF THE INVENTION

(5) In the following, the figures will be described in more detail. FIG. 1 illustrates a first exemplary embodiment of the method according to the invention. To provide a clothing 10, for example a woven dryer fabric, with an edge protector 12, the clothing 10 is firstly stretched over two rotatably mounted rolls, namely a first tensioning roll 14 and a second tensioning roll 16. A film strip 18, which can be wound up on a roll 20, is then applied to one of the two side edges of the clothing 10. For this purpose, the film strip 18 is guided over a pressure roll 22. The pressure roll 22 can be or is positioned here in such a way that, together with an opposing roll 23, it exerts a predefined pressing force on the film strip 18 when the latter is guided together with the clothing 10 through a gap 24 between pressure roll 22 and opposing roll 23. The pressing force on the film strip 18 is dimensioned here such that the film strip 18 substantially completely penetrates the woven material of the clothing 10, so that the threads of the clothing 10 in the region of the side edge are enclosed completely by the film strip 18. In order that the penetration of the woven material by the film strip 18 becomes possible, both the woven material and the film strip 18 are warmed previously, so that they melt slightly. To this end, use is made of a hot air source 26, which is oriented in such a way that a jet of hot air, which is indicated by three parallel arrows in FIG. 1, is directed into the gap 24. Preferably, the amount of heat is calculated such that the threads in the edge region of the woven clothing 10 melt and soften only at the surface, whereas the film strip 18 is softened almost over its entire thickness. The method can be continued continuously until the clothing 10 has been provided with the edge protector 12 along its entire circumference. Subsequently or simultaneously, that edge of the clothing which is opposite in the cross-machine direction can also be provided with an edge protector 12 in the same way.

(6) FIG. 2 illustrates a second exemplary embodiment of the method according to the invention. The same designations relate here to the same components or component sections as in the embodiment in FIG. 1. To this extent, only the differences from the embodiment in FIG. 1 will be discussed below, and otherwise reference is made to the above description. The essential difference between the first embodiment and the second embodiment consists in the pressure roll 22 not forming a gap 24 in interaction with the opposing roll 23, by which gap a pressing force is exerted on the film strip 18, but instead, such a gap is formed in the interaction of the pressure roll 22 with a plate 28. The plate 28 can be substantially flat, i.e. have a surface which faces the pressure roll 22 and which is substantially flat. The plate 28 preferably has here an inlet slope (at its left-hand end in FIG. 2). The hot air source 26 again has to be positioned such that it directs a jet of hot air into the gap between pressure roll 22 and plate 28.

(7) FIG. 3 illustrates a third exemplary embodiment of the method according to the invention. The same designations refer here to the same components or component sections as in the embodiment in FIG. 2. To this extent, only the differences from the embodiment in FIG. 2 will be discussed below, and otherwise reference is made to the above description relating to the first two embodiments. The essential difference between the second embodiment and the third embodiment consists in the pressure roll 22 of the second embodiment having been replaced by a further plate 30 which forms a gap in interaction with the plate 30, by which gap a pressing force is exerted on the film strip 18. The two plates 28, 30 together preferably form here a tapering gap, through which the clothing 10 is guided together with the film strip 18, in order that the film strip 18 is pressed through into the woven material of the clothing 10 and preferably penetrates said woven material completely. The hot air source 26 is positioned as in the second embodiment.

(8) FIG. 4 shows a plan view of the clothing 10 which is stretched over the two tensioning rolls 14, 16 and which, at its two side edges, is provided with a respective edge protector 12. Preferably, the two side edges are then further trimmed, for example by means of ultrasound technology, in order to obtain smooth edges and a clothing with an accurately defined width. The threads of the woven material are protected so well here by the form-locking and integral connection that it is almost impossible for individual threads to be detached out of the edge protector 12. Rather, individual thread ends which project out of the edge protector 12 under certain circumstances tend to break off.

LIST OF DESIGNATIONS

(9) 10 Clothing

(10) 12 Edge protector

(11) 14 First tensioning roll

(12) 16 Second tensioning roll

(13) 18 Film strip

(14) 20 Roll

(15) 22 Pressure roll

(16) 23 Opposing roll or further roll

(17) 24 (Inlet) gap

(18) 26 Hot air source

(19) 28 Plate

(20) 30 Further plate