阅读说明：本技术 用于制造纤维幅材的机器的绷网以及这种绷网的制造方法 (Clothing for a machine for producing a fibrous web and method for producing such clothing ) 是由 米夏埃尔·斯特劳布 于 2019-01-18 设计创作，主要内容包括：本发明涉及用于制造纤维幅材、尤其是纸幅材或纸板幅材的机器的绷网,绷网基本上由薄膜状的材料(12)形成,薄膜状的材料具有面朝纤维幅材的第一表面(14)和背离纤维幅材的第二表面(16),其中,绷网包括多个贯通开口(24),贯通开口分别沿着中心轴线(32)从第一表面(14)延伸到第二表面(16),其中,绷网的至少一些贯通开口(24)的中心轴线(32)相对于第一表面(14)夹成不同于90°的角度。此外,本发明还涉及用于制造纤维幅材、尤其是纸幅材或纸板幅材的机器,该机器包括这种绷网,并且涉及用于制造这种绷网的方法,其中,贯通开口(24)借助激光器被引入到薄膜状的材料(12)中。(The invention relates to a clothing for a machine for producing a fiber web, in particular a paper or cardboard web, which is essentially formed from a film-like material (12) having a first surface (14) facing the fiber web and a second surface (16) facing away from the fiber web, wherein the clothing comprises a plurality of through-openings (24) which each extend along a central axis (32) from the first surface (14) to the second surface (16), wherein the central axes (32) of at least some of the through-openings (24) of the clothing enclose an angle different from 90 DEG with respect to the first surface (14). The invention further relates to a machine for producing a fiber web, in particular a paper or cardboard web, comprising such a clothing, and to a method for producing such a clothing, wherein through-openings (24) are introduced into a film-like material (12) by means of a laser.)

1. Tenter web (10) for a machine for producing a fiber web, in particular a paper or cardboard web, essentially formed by a film-like material (12) having a first surface (14) facing the fiber web and a second surface (16) facing away from the fiber web, wherein the tenter web (10) comprises a plurality of through openings (24) extending along a central axis (32) from the first surface (14) to the second surface (16), respectively,

It is characterized in that the preparation method is characterized in that,

the central axes (32) of at least some of the through-openings (24) of the clothing (10) enclose an angle different from 90 DEG with respect to the first surface (14).

2. A clothing web (10) according to claim 1, characterized in that the central axes (32) of at least two through openings (24) have mutually different angles with respect to the first surface which differ from 90 °.

3. Clothing (10) according to claim 1 or 2, characterized in that the central axis (32) of at least one through-opening (24) has a direction component (RK) oriented parallel to the longitudinal direction (LR) of the clothing (10).

4. Clothing (10) according to claim 3, characterized in that a majority, preferably all, of the central axes (32) of the through-openings (24) having such a direction component (RK) are directed in the same direction, the direction component (RK) being formed parallel to the longitudinal direction (LR) of the clothing (10).

5. Clothing (10) according to one of the preceding claims, characterized in that the central axis (32) of at least one through-opening (24) has a direction component (RK) oriented parallel to the transverse direction (QR) of the clothing.

6. Framework (10) according to claim 5, characterized in that a direction component (RK) of the central axis (32) of substantially half of the through-openings (24) having such a direction component (RK) constituted parallel to the transverse direction (QR) of the framework is directed in the opposite direction to a direction component (RK) of the central axis (32) of the remaining through-openings (24) having such a direction component (RK) of the central axis (32) thereof.

7. Screen (10) according to claim 6, characterized in that the screen (10) is delimited by a first side edge (34) and a second side edge (36), wherein the through-openings (24) whose central axis (32) has direction components (RK) extending parallel to the transverse direction (QR) all pointing in the same direction are arranged closer to the first side edge (34) of the screen (10) than the through-openings (24) whose central axis (32) has direction components (RK) extending parallel to the transverse direction (QR) pointing in opposite directions.

8. Clothing (10) according to one of the preceding claims, characterized in that the clothing (10) has two side edges (34, 36) delimiting the clothing, wherein, in particular as viewed in the transverse direction (QR) of the clothing (10), the center axis (32) of at least one through-opening (24) in an edge region adjacent to one of the two side edges (34) has an angle deviating more from 90 ° relative to the first surface (14) than the center axis (32) of at least one other through-opening (24) in a center region arranged centrally between the two side edges (34, 36) of the clothing.

9. Tenter (10) according to any of the preceding claims, characterized in that the central axes (32) thereof have a direction component (LR) of the central axes (32) of most, preferably all, of such direction components (RK) oriented parallel to the longitudinal direction (LR) of the tenter (10) pointing in the same direction.

10. A clothing (10) according to any one of the preceding claims, characterized in that the clothing (10) is a forming net.

11. Machine for manufacturing a fibrous web, in particular a paper or cardboard web, comprising a stretch fabric (10) according to any one of the preceding claims.

12. Machine according to claim 11, characterized in that the clothing (10) is incorporated in the forming section of the machine.

13. Machine according to claim 11 or 12, characterized in that the clothing (10) is installed in the machine in such a way that the direction component (RK) of the central axis (32) of the machine, which is oriented parallel to the longitudinal direction (LR) of the clothing (10), of the central axes (32) of most, preferably all, of the direction components (RK) of the through openings (24) points in the opposite direction to the direction of travel (MD) of the clothing (10).

14. Method for producing a clothing (10) according to one of claims 1 to 10, characterized in that the through-openings (24) are introduced into the film-like material (12) by means of a laser.

15. Method according to claim 14, characterized in that at least two through openings (24) having mutually different angles different from 90 ° with respect to the first surface (14) are introduced into the film-like material (12) by means of mirror optics functionally connected with the laser.

Technical Field

The invention relates to a clothing for a machine for producing a fiber web, in particular a paper or cardboard web, which is essentially formed from a film-like material and has a first surface facing the fiber web and a second surface facing away from the fiber web, wherein the clothing comprises a plurality of through-openings which each extend along a central axis from the first surface to the second surface.

Background

Nowadays, the clothing of machines for manufacturing fiber webs, for example the forming wire for paper machines, is still mostly woven. However, the weaving process is expensive and time consuming. For this reason, attempts have been made for a long time to produce such a stretching net from a film-like material which consists of plastic and can be extruded inexpensively. The film-like material can either be produced in a single layer or can have a plurality of layers which together form a laminate. In order to make the film-like material permeable to water, the film-like material must have through openings. Various methods have already been proposed for this purpose, such as stamping, mechanical drilling or the provision of pore formers in the film-like material, which form through-openings after activation.

It should be noted at this point that the term "film-like material" is preferably understood in the sense of the present invention to mean, in particular, but not necessarily, an extruded plastic film. Thus, the term may refer to any type of flat and flexible object that is not made by weaving, such as a felt or a non-woven fabric.

It has proven to be particularly advantageous to introduce the through-openings into the film-like material by means of a laser, wherein the energy of the laser is used to evaporate the film-like material. Such methods are described, for example, in US 5,837,102 and WO 2012/028601 a 1. Fig. 1 shows schematically how the method works, wherein only sections of a film-like material 12 are visible in fig. 1, which form the base substrate of the clothing 10 to be produced (see fig. 4). The film-like material 12 has a first surface 14, which faces the fiber web during the intended use of the clothing 10, and a second surface 16, which is opposite the first surface 14 (see fig. 4). Optionally, as indicated in fig. 1, the first surface 14 may have elevations 18 and/or depressions 20 introduced, for example, by embossing. However, the first surface 14 and the second surface 16 may be presented substantially flat. A series of through openings 24 are introduced into the film-like material 10 by means of the laser 22, which extend from the first surface 14 to the second surface 16. For this purpose, the laser 22 is controlled by a controller 26 via a line 28 and emits radiation pulses 30 at predetermined intervals while the laser is moved relative to the film-like material 12. However, it is also possible to move the film-like material 12 in sections at all times relative to the laser 22 and then drill the hole in a stationary state.

As can be seen in the sectional views through the film-like material 12 in fig. 2 and 4, the circumferential wall sections of the through-openings 24 extend substantially rotationally symmetrically about the respective center axis 32 of the through-openings 24. The through-opening 24 can have a substantially right-circular-cylindrical shape, as shown in fig. 2, or a conical widening or tapering, as shown in fig. 3. The respective central axis 32 extends here always straight substantially perpendicularly to the first surface 14 or the second surface 16.

The film-like material 12 perforated in this way can then be used to produce the stretching net 10 shown in fig. 4. For this purpose, the longitudinal ends of the web-like, film-like material 12 are usually connected to one another in the region of the seam in order to render the clothing 10 seamless. The screen 10 is bounded by a first side edge 34 and a second side edge 36. Furthermore, the fleece 10 has a longitudinal direction LR running parallel to the side edges 34 and 36 and a transverse direction QR running orthogonally to the side edges 34 and 36.

It has been shown that in the aforementioned clothing known from the prior art, the drainage properties are not always optimal. A further problem in these gauzes is that the film-like material is strongly structurally weakened by the large number of through-openings. This has a negative effect on their ability to absorb forces acting on the machine during its intended use, in particular in the longitudinal direction.

Disclosure of Invention

The object of the present invention is to solve the above problems or at least to reduce them to a minimum. This is achieved by the solution according to the independent claims. Advantageous developments of the invention are the subject matter of the dependent claims.

In particular, this object is achieved by a clothing of the generic type and mentioned at the outset, which is additionally characterized in that the center axes of at least some of the through-openings of the clothing enclose an angle other than 90 ° with respect to the first surface. The deviation is preferably at least 1 ° and/or at most 45 °, more preferably at least 2 ° and/or at most 30 °, and still more preferably at least 5 ° and/or at most 20 °.

It has been found that such an angular deviation, hereinafter referred to as inclination, of the central axis of the through-opening with respect to the orthogonal line of the first surface has an influence on the drainage capacity of the through-opening. This result can be used in a targeted manner to influence the drainage capacity of the entire screen as required. If, for example, the center axis of the through-openings is inclined from the first surface facing the fiber web during the intended use in the opposite direction to the direction of movement of the clothing, suction forces act in the through-openings due to the movement of the clothing, which forces promote rapid drainage of the fiber web. This makes it possible, for example, to provide fewer through-openings in the film-like material with the same drainage properties and/or to reduce the diameter of the through-openings, so that the film-like material is weakened to a lesser extent by the through-openings and can receive a greater tensile force. If, on the other hand, the center axis of the through-openings is inclined from the point of view facing the first surface of the fiber web in the intended use to the direction of movement of the clothing, then, as a result of the movement of the clothing, blocking forces act in the through-openings, which slows down the drainage rate of the fiber web. This makes it possible to perform the drainage more gently and locally. This effect is also promoted by the channel length of the through-openings being increased due to the inclination. To achieve this, the center axis of the through-opening can additionally or alternatively also be inclined from the first surface to one of the two lateral edges of the clothing.

It is particularly advantageous if the central axes of at least two through openings have angles different from each other, different from 90 ° with respect to the first surface. Thus, different regions of the clothing are affected differently in terms of their drainage properties.

As already mentioned above, it can be provided that the central axis of the at least one through-opening has a directional component oriented parallel to the longitudinal direction of the clothing.

In this case, it is advantageous if a majority, preferably all, of the direction components of the center axes of the through-openings having such a direction component, which are formed parallel to the longitudinal direction of the clothing, are directed in the same direction. For example, all through-openings can have a central axis with a directional component which, in the intended use, is directed from the first surface against the direction of travel of the clothing, in order in this way to increase the drainage capacity of the clothing.

As also described above, it is alternatively or additionally also possible for the central axis of the at least one through-opening to have a directional component oriented parallel to the transverse direction of the clothing.

In this case, it can be advantageous if the direction component of the central axes of approximately half of the through-openings, whose central axes have such a direction component, which is formed parallel to the transverse direction of the clothing, is directed in the opposite direction to the direction component of the central axes of the remaining through-openings, whose central axes have such a direction component, which is formed parallel to the transverse direction of the clothing.

It is proposed that the clothing is delimited by a first side edge and a second side edge, wherein the through-openings whose central axes have all direction components which point in the same direction and which extend parallel to the transverse direction are arranged closer to the first side edge of the clothing than the through-openings whose central axes have direction components which point in opposite directions and which extend parallel to the transverse direction. In this way, for example, the drainage capacity of the clothing can be designed symmetrically with respect to the central region arranged between the two side edges of the clothing.

In addition, an advantageous development provides that the clothing has two side edges delimiting the clothing inlet, wherein, in particular, as viewed in the transverse direction of the clothing, the center axis of at least one through-opening in the edge region adjacent to one of the two side edges has an angle deviating more from 90 ° with respect to the first surface than the neutral axis of at least one other through-opening in the intermediate region arranged centrally between the two side edges of the clothing. Thus, for example, the drainage capacity of the clothing may decrease continuously from a central region arranged centrally between the two lateral edges of the clothing towards the two lateral edges.

Furthermore, the direction components of the majority, preferably all, of the central axes of the through openings having such a direction component, which are oriented parallel to the longitudinal direction of the clothing, can point in the same direction.

As already mentioned at the outset, the clothing according to the invention can be a forming wire, in particular of a paper machine, i.e. a wire on which a fiber suspension is applied and through which the greatest part of the water contained in the fiber suspension is drained.

A further aspect of the invention relates to a machine for producing a fiber web, in particular a paper or cardboard web, comprising a clothing according to the invention as described above.

The clothing may be incorporated in the forming section of the machine. In principle, however, other parts or sections of the machine are also conceivable.

The clothing is preferably installed in the machine in such a way that the direction component of the central axis of the clothing, which is oriented parallel to the longitudinal direction of the clothing, of a majority, preferably all, of the central axes of the through-openings, points in the opposite direction to the direction of travel of the clothing. This can improve the drainage ability of the stretched net.

A further aspect of the invention relates to a method for producing the aforementioned clothing according to the invention, wherein the through-openings are introduced into the film-like material by means of a laser.

In this case, it is particularly preferred that at least two through openings are introduced into the film-like material by means of mirror optics which are functionally connected to the laser, the through openings having angles which differ from one another and differ from 90 ° with respect to the first surface. The inclination of the central axis of the through-opening can be set inexpensively by means of the mirror optics, without the entire laser having to be inclined toward the first surface of the film-like material. It is also possible to produce the entire row of through-openings in the film-like material in a short time by means of only one laser, in that the mirror in the mirror optics is correspondingly simply adjusted.

Drawings

The invention is further elucidated below with the aid of a schematic drawing which is not drawn to scale. Wherein:

fig. 5 shows a cross-sectional view of a section of film-like material along the longitudinal direction of the clothing according to the invention;

fig. 6 shows a cross-sectional view of a section of film-like material along the transverse direction of the clothing according to the invention.

Detailed Description

Fig. 5 shows a schematic cross-sectional view of a section of the film-like material 12 along the longitudinal direction LR of the clothing 10 according to the invention. The clothing 10 or the film-like material 12 has a first surface 14 which, during the intended use of the clothing 10, faces the fibrous web formed thereon, and a second surface 16 which is opposite the first surface 14. It can also be seen that, between the first surface 14 and the second surface 16, six through-openings 24 extend through the film-like material 12. Drainage of the fibre suspension for forming the fibre web can be performed through these through openings 24. Each of the through openings 24 has a respective central axis 32, which is straight and is shown in the figure by a dashed line. The walls of the through-openings 24 extend rotationally symmetrically about the respective central axis 32. In the present exemplary embodiment, the through-openings 32 are both of cylindrical design, but they can also be of conical design, i.e. widen toward the first surface 14 and/or the second surface 16.

The two through openings 24 shown on the left side of fig. 5 have a central axis 32 extending substantially orthogonal to the first surface 14. This therefore corresponds to the prior art described in relation to fig. 1.

In contrast to this, the two through openings 24 shown in the middle of fig. 5 have central axes 32 which enclose an angle, which can be seen, different from 90 degrees with respect to the first surface. In particular, the center axes 32 of the two through openings 24 are inclined relative to the first surface 14 in such a way that the center axes 32 have a directional component RK which is oriented parallel to the longitudinal direction LR of the clothing 10. In a specific use, the direction component RK is also oriented in the same direction as the direction of travel MD of the clothing 10. The dynamic forces acting during operation of the screen 10 lead to a blocking effect in the central two through-openings 24, so that the drainage takes place more slowly in these two through-openings than in the left two through-openings 24 whose central axes are oriented substantially orthogonally to the first surface 14.

The two through openings 24 shown on the right in fig. 5 also have central axes 32 which enclose an angle which can be seen different from 90 ° with respect to the first surface. The center axes 32 of the two through openings 24 are also inclined relative to the first surface 14 in such a way that the center axes 32 have a directional component RK which is oriented parallel to the longitudinal direction LR of the clothing 10. In contrast to the two through openings 24 shown in the middle in fig. 5, the directional component RK of the two through openings 24 is directed in the intended use in the opposite direction to the direction of travel MD of the clothing 10. The dynamic forces acting during operation of the screen 10 lead to a suction effect in the two right through-openings 24, so that in these two through-openings the drainage is accelerated compared to the two left through-openings 24 whose central axes 32 are oriented substantially orthogonally to the first surface 14 and the first right relative to the two central through-openings 24.

Fig. 6 shows a schematic cross-sectional view of a section of a film-like material 12 along the transverse direction QR of a clothing 10 according to the invention. Five through-openings 24 can be seen in fig. 6, which extend through the film-like material 12 between the first surface 14 and the second surface 16, respectively. Wherein each through-opening 24 again has a respective central axis 32 which is of straight design. The walls of the through-openings 24 extend here substantially rotationally symmetrically about the respective central axis 32.

The through opening 24, which is shown centrally in fig. 6, has a central axis 32 extending substantially orthogonal to the first surface 14. This therefore corresponds to the prior art described in relation to fig. 2.

In contrast, the two through openings 24 shown on the left in fig. 6 have central axes 32 which enclose an angle of view different from 90 ° with respect to the first surface 14. In particular, the center axes 32 of the two through openings 24 are inclined relative to the first surface 14 in such a way that the center axes 32 have a directional component RK which is oriented parallel to the transverse direction QR of the clothing 10. The direction component RK is directed to the left in fig. 6 for the two through openings 24.

The two through openings 24 shown on the right in fig. 6 also have central axes 32 which are at an angle which can be seen to differ from 90 ° with respect to the first surface. The center axes 32 of the two through openings 24 are also inclined relative to the first surface 14 in such a way that the center axes 32 have a directional component RK which is oriented parallel to the transverse direction QR of the clothing 10. In contrast to the two through openings 24 shown on the left in fig. 6, the directional components RK of the two through openings 24 point in opposite directions, i.e., to the right in fig. 6.

It can also be seen from fig. 6 that the inclination of the central axes 32 of the two outermost through openings 24 with respect to the normal to the first surface 14 is greater than the inclination of the central axes 32 of the two through openings 24, which are respectively arranged between the central through opening 24 and the two outer through openings 24. The greater the inclination, the greater the passage length of the respective through opening 24 and the slower or more gradual the drainage takes place. It can be advantageous if the through-opening 24 shown in the middle of fig. 6, whose central axis 32 is oriented substantially orthogonally to the first surface 14, is also arranged in the middle region located centrally between the two side edges 34 and 36 (see fig. 3) of the clothing. In this way, a substantially symmetrical drainage profile with respect to the transverse profile of the clothing 10 can be achieved.

It is to be understood that the examples shown in fig. 5 and 6 are only intended to illustrate the basic principle of the invention. The inclination of the individual through openings with respect to the central axis of the first surface can be set in different ways on the clothing as required in order to obtain an optimum fiber web adapted to the requirements.

List of reference numerals

10 stretching net

12 film-like material

14 first surface

16 second surface

18 raised portion

20 recessed part

22 laser

24 through opening

26 controller

28 line

30 pulses of radiation

32 central axis

34 first side edge

36 second side edge

LR longitudinal direction

QR transverse direction

Component of RK direction

Direction of travel of MD