JPS62268893A - Wirescreen for paper layer forming part of papermaking machine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a double-woven paper net for the paper layer forming section of a paper making machine, which is constructed by having weft yarns arranged in an upper layer and a lower layer, and interweaving them with warp yarns. . In this case, the weft and warp yarns of the upper layer are woven in a linear manner (crimp) to form a surface against the paper surface. Also, the warp yarns of the repeating unit are woven twice with the weft yarns of the upper layer, The number of weft threads in the upper layer is twice the number of weft threads in the lower layer.

The double woven paper net as above is DE-A-226347
6,2540490 and 2706235 and EP-
A-30490 is already known. In the case of the fabric shown in FIG. 2F of DE-A-2706235, the weft density of the upper layer is also twice that of the lower layer. Although this type of paper layer forming screen is much improved in terms of marking compared to heavy paper layer forming screens, it is still not suitable for producing paper that is sensitive to markings. There's a problem.

According to DE-A-2706235, the marking properties are improved by making the floating portion of the weft yarn very long. Also, similar to US-A-4333502, EP-A-3
0490 similarly attempts to improve marking performance by lengthening the floating portion of the chain.

The present invention was started based on DB-A-2706235 with the object of providing a paper layer forming screen that does not cause marking properties.

This problem is solved according to the invention by the fact that the first weft thread of the upper layer forms a linear (crimp) component in contact with the plane of the paper, and that this part is supported by a saddle of the linear component formed by one warp thread; The second weft yarns of the top layer and the second weft yarns arranged alternately with the first weft yarns form a linear component in contact with the paper surface, and these parts are adjacent to each other, and one of the second weft threads is arranged from within the woven structure to the paper surface. This is solved by the fact that it is supported by two warp threads, one of which is the thread that comes down from the surface of the paper, and the other that goes down into the weaving structure from the plane of the paper.

When the weft threads are supported by the saddle of a linear component of the warp threads, the warp threads pass under the weft threads at the front and back of that section, but above the weft threads at that section. In this case, an upward force acts on the weft.

In the case of the paper net according to the present invention, the first weft of the upper layer is supported in such a state.

In the upper layer, the first weft threads are arranged alternately with the second weft threads. The second weft is created by two warp threads meandering next to each other, one coming up from within the weave to the surface of the paper, and the other thread entering from the surface of the paper into the weave. It is supported by two warp threads.

In this case, when the warp threads pass under the two weft threads in the upper seven rules, they are considered to be passing through the interior of the fabric. In this suspended state, an upward force acts on the weft with respect to the plane of the paper, and at the same time a rotational moment acts on the weft that causes the weft to be transmitted from the lateral direction.

Because the weft threads are supported in these two ways, the floating parts of the weft threads are not all lined up in parallel, but are arranged in two different ways.

That is, one and the other of the two types of floating portions of the weft are lined up at a certain angle to each other. This disrupts the regular markings on the paper, so that the markings on the paper are blurred and almost invisible.

In a particularly advantageous embodiment of the invention, the warp threads pass successively over the two upper weft threads before and after the saddle of each linear component, and furthermore the warp threads pass longitudinally one after the other over the upper weft threads. There is a discrepancy between every six weft threads.

This provides a large number of short floating portions formed by the warp and weft, that is, a large number of fulcrums for the paper layers. That is, by shortening the floating portions of the warp and weft, marking properties are significantly improved.

For the warp and weft threads, it is expedient to use synthetic resin monofilaments, especially polyester monofilaments. In this case, in order to increase wear resistance, the weft yarns of the lower layer are thicker than the weft yarns of the upper layer.

The abrasion resistance can be further improved by using, in part, a material exhibiting particularly good abrasion resistance, such as polyamide, as the weft thread of the lower layer.

It is impossible to completely flatten the surface corresponding to the paper surface by the weaving process alone. As is already known, by heat-treating the paper net while stretching it in the machine direction, the high portions of the linear constituent parts of the warp and weft yarns on the paper side can be brought back into the plane. In general, it is easier to flatten completely when using an open weave for endorenu weaving.

Next, embodiments of the present invention will be described based on the drawings.

As is clear from the longitudinal cross-sectional view in Figure 1, the double-layered net is
The first weft (3) and the second weft (4) are arranged alternately.
) and a lower layer (2) made of weft yarns (5). And the warp (6) is the upper layer fl)
The weft (4) of the weft (21) and the weft (2) of the lower layer (
By interweaving with 51, both layers are bonded.

The weft density of the upper layer is twice that of the lower layer, in which case the upper layer (
The second weft of 1) and the weft of the lower layer (2) are woven so as to overlap as much as possible.

The warp threads (6) each have a weave structure - an upper layer (1
) are mixed twice. In other words, the warp (6
) is above the weft (4) of the next two wefts (21), below the first weft (3), and the two wefts (3), (4).
), (31 top and weaving progresses. By this, the upper layer (
In 1), the warp (6) forms a saddle, on which the first weft (3) is supported. In this case, the weft (3
) only has an upward force acting on it. Next, the warp (6
) between the upper layer (1) and the lower layer (2), with four weft threads (3), (3), and (4) of the upper layer (1), or two weft threads (5) of the lower layer (2). After advancing the distance, it passes under one weft thread (5) of the lower layer (2). As a result, the warp threads (6) are mixed with the lower layer (2). After this, the warp threads (6) pass again between the upper layer (1) and the lower layer (2) and rise upwards to weave the weave structure-repetitive unit of the next upper layer (1).

By heat-treating the fabric while stretching it in the vertical direction,
The highly protruding linear component (7) of the first weft, the linear component (8) of the second weft, and the linear component (9) of the warp (6) are on one plane, that is, a surface corresponding to the paper surface αQ,
Become able to accomplish the following. By heat-treating while stretching in the longitudinal direction, the weft (5) of the lower layer (2) also becomes the warp (6).
It bites under the warp (6) and lifts it up a little. As a result, the lowest warp (6) in the lower layer (2) is positioned slightly above the running surface formed by the remaining wefts (5) in the lower layer (2),
As a result, wear is largely avoided. The paper net is therefore a so-called weft runner (in the case of open weaving, it is a weft runner).

In FIG. 2, the warp threads (6) are arranged so that the weft threads (3) and (4) of the upper layer (1) are staggered every six in the longitudinal direction. Thus, as can be seen in FIG. 1, the warp (6) intersects with the next warp under the second weft (4) of the upper layer (1). As a result, the second weft (4) is supported in a bifurcated manner, so that an upward force is applied to the second weft (4), and at the same time, a force that slightly rotates it in the lateral direction on the fabric surface is also applied.

Therefore, the upper layer is the linear component (8) of the second weft (4) of )
is no longer parallel to the linear component (71) of the first weft (3).

The weaving structure shown in Figures 1 to 3 is the weft (2) of the lower layer (2).
5) Seven threads and warp threads (6) Repeated every seven threads, so
It has an upper shaft structure. In other words, the structure is the weft (5) of the lower layer (2).
) 7 yarns, warp (6) 7 yarns, and upper layer (1) weft yarn (2
1) is repeated every 14 wefts (4). In that case, the first weft (3) and the second weft (4) can be made of the same material and have the same thickness. However, it is advisable to choose a flexible material for the second weft thread (4), and also a thicker thread than the first weft thread is expedient, so that the linear component (8 ) can pass while taking a larger angle in the lateral direction, which is effective in eliminating markings.

The embodiment shown in FIGS. 4-6 is substantially similar to the embodiment of FIGS. 1-3, but in this case with an eight-axis configuration. In this case as well, the warp threads (6) each form two linear components (9) in the upper layer (1), between which passes a first weft thread (31), which is A linear groove bottom portion (7) is formed in the direction.

Similarly, as a result of the second weft (4) being supported by the two warp threads (6) that intertwine, the second weft thread (4)
The linear groove bottom portion (8) curves in the lateral direction. The warp threads (6) are different from each other every six weft threads.

As is clear from the comparison between Figures 2 and 5, the warp (6)
The linear component (9) of is very uniformly distributed.

However, since the linear components (7) and (8) are tilted relative to each other, it is not monotonous. In particular, no diagonal paths, such as those marked on paper, occur.

The two linear components (9) of the warp (6) are combined into one weft (
Instead of 3), it is also possible to divide by a total of five weft threads. When divided by three weft threads,
Each weft thread of the upper layer [11 forms two differently shaped linear components. In this case, the linear components run at an angle to each other. When a linear component is divided by five weft threads in the upper layer (1), the weft threads are raised above the four warp threads;
Since only one type of linear groove bottom is produced, it is of no use in eliminating markings.

3 and 6 are fabric patterns for the embodiments of FIGS. 1 and 2 through 4 and 5. FIGS. Third
Numbers 3 to 6 shown at the bottom of the diagram
Numbers 8 to 8 in the figure are warp threads, and numbers 21 to 21 on the left end. Or 1 to 24 are weft yarns.

In Figure 3, weft yarns numbered 1, 4, 7, 10, etc. are the first weft yarns (
3), and the other weft threads numbered 2.5.8 correspond to the second weft thread (4) supported by the warp threads crisscrossed in a scissor-like manner. The wefts with numbers 3, 6, 9, etc. are the wefts +51 of the lower layer. In Figure 6, the wefts with numbers 2, 5, 8, 11, etc. belong to the lower layer, and the wefts with numbers 1, 4, 7, etc. are the first weft (3) supported by the saddle of the linear component. The weft threads, such as numbers 3, 6, and 9, have a second weft thread (4) that is supported in a scissor-like manner.

Each square on the textile pattern marks the intersection of the weft and warp threads. In this case, the black square indicates that the warp is above the weft, while the square on the mortar indicates that the weft of the upper layer [11] is above the warp (6). A square with black dots indicates that the weft threads of the lower layer (2) are above the warp threads (6) when viewed from the paper side.

This part is the part where the lower layer is connected by the warp threads (6).

The paper net according to the present invention usually has a warp density of 90 to 11.
It is woven and heat treated so that it becomes 0%. Typical warp density values are 1 (10 to 105%).However, for tissue paper it is more convenient to choose a slightly lower value. - It can also be produced according to AOO 48962, only in this case part of the warp threads (6) are interwoven with the weft threads (5) in the lower layer (2), while the remaining warp threads are interwoven with the weft threads (21) of the upper layer (1). The weave 9 is matched only with the wefts (3) and (4) of the weft 9. As a result, wear on the running side is suppressed.

This embodiment according to the invention is shown in cross section in FIGS. 7 and 9. The embodiment shown in FIG. 7 is then essentially the same as the embodiment shown in FIG. The difference is that the second warp U is not interwoven with the lower layer (2).

The ratio of warp threads (6) to warp threads (10) can be selected.The warp threads (6) are woven twice in the upper layer (1) and twice in the lower layer (2) per tissue unit. The warp threads (16) are interwoven twice in the upper layer (1) of the weaving unit, but are not interwoven at all in the lower layer (2).As a result, on the running side, the weft threads are very long, i.e. A floating section is formed which spans 13 warps as shown in the figure.On the paper side, it is exactly the same as the embodiment shown in FIGS. 1 and 2.

FIGS. 9 and 10 also illustrate one embodiment of a paper making screen. In this case, the warp threads (6) are interwoven twice in the upper layer (1) and twice in the lower layer per weaving unit. The other warp (L mark is the upper layer per tissue unit (1)
In the lower layer (2), two layers of weave υ are mixed, but in the lower layer (2), there is no weave mixed at all. In this case, on the running side, the weft threads are relatively short, ie they form a floating section spanning seven warp threads, as shown in FIG.

On the other hand, the paper side of this embodiment is the same as the embodiment shown in FIGS. 4 and 5, and there is no difference with respect to the weave structure in the upper layer (1).

The paper making screen according to the invention is EP-A-012033
Similarly to No. 7, the weave structure of the two parts divided along the longitudinal center line has mirror symmetry, and the diagonal lines of the structure are reversed at the center to form a V-shape. This makes it possible to prevent the paper screen running in the paper making machine from drifting sideways or elongating.

By supplementing the warp threads 4 to the central portion, the length of the floating portion of the weft can be completely shortened, and therefore, substantially no long floating portions occur even on the boundary line of the mirror-symmetric image area. Figure 11 shows a part of such a papermaking net, and the supplementary warp garden is also shown.

FIG. 12 is a longitudinal sectional view of an embodiment in which three layers of wefts are arranged. In this case, in the upper layer (2) J and immediately below it, i.e. in the middle layer, the weft threads are exactly the same as in the upper layer (1) and the lower layer (2) shown in FIG.
It is interwoven with the warp (6).

Further down in Figure 12, the lower layer (23) is a supplementary weft (251 layer) whose weft Q51 is interwoven with the weft (5) of the intermediate layer by the warp (27).Thus, the overall In this case, each warp yarn is simply interwoven with the weft yarn in two overlapping layers. In this case, the weft yarn α of the lower layer 123] is interwoven with the weft yarn of the middle layer (123).
It is expedient to arrange them at a density similar to 5). Fabrics with such structure are D B-A-32255
99 is described in detail. Paper side of this embodiment
ii weave is the same as that shown in FIG.

Example 1 A paper net having the upper shaft structure shown in FIGS. 1 to 3 is woven by open weaving. The warp threads are made of polyester monofilament with a diameter of 0.158 and a high elastic modulus. The warp density becomes 71 threads/1 by heat treatment.

The first weft (3) of the upper layer (1) has a diameter of 0.17u,
Moderate elastic modulus (load 27 cN/lex 19
% elongation) is used. The second weft (→ has a diameter of ○, 185 mm, and a relatively low elastic modulus (23.4 at a load of 27 CN/lex)
% elongation) using polyester monofilament.

After heat treatment, the weft density in the upper layer (1) is 36 in total.
/crR.

The weft yarns (5) of the lower layer (2) forming the running side are made of a very flexible polyester monofilament of 0.20 thread (23.4% elongation at a load of 27 cN/tex) and a flexible @0.20 thread diameter. 2117i polyamide monofilaments are used alternately. After heat treatment, the weft density in the lower layer (2) is 18/α in total.

By heat treatment, the first weft (3
) and the linear component (7) of the second weft (4) and (
8) Furthermore, the linear component (9) of the warp threads (6) forms one plane. The fabric thus becomes a single plane fabric.

On the other hand, on the running side, the warp (6) and weft (6)
) A surface difference of 7.5/1 (10ifl) occurs, and the paper net becomes a weft runner.During weaving and heat treatment, the upper layer (1)
Care was taken that the first weft thread (3) of the was located exactly on the weft thread (5) of the lower layer (2).

Example 2 The biaxially structured paper net shown in FIGS. 4 to 6 was woven by open weaving, heat treated, and then finished into an endless piece by weaving. Weave so that the number of warp threads is 54/1. As a result of the weft shrinking due to the heat treatment, the warp number becomes 60/an. The warp has a diameter of 0
．． A length stable polyester monofilament with a 17-plane diameter and a high modulus of elasticity is used.

The upper layer weft (3) has a diameter of ○, 17" and is relatively hard (Trevira, which has a relatively high elastic modulus suitable for a weft, elongates by 8.5% at a load of 27 CN/leX)
902 type) Polyester monofilament is used. Similarly, polyester seven filaments are used for the weft (4) of the upper layer (1), but in this case, the diameter is Q,
23.4 at 20M and load 27 cN/tex
A flexible Trevira 9 (type 10) with % elongation is used. This fabric is woven so that the total weft density is 3571, but the number of wefts in the upper layer (1) is reduced to 32 by heat treatment.
/α and the lower layer (2) is 16, /am.

The weft yarn (5) of the lower layer (2) has a diameter of 0.22 fl, and has a diameter of 27
Flexible Tre stretching 23.5% in CN/leX
vi-ra 9 (type 10 polyester monofilament and PA6.6 type polyamide monofilament having a diameter of 0.24'U are used alternately. Heat treated at 195"C. This results in a maximum longitudinal stress of 95N10++. During the heat treatment process, the warp and weft threads are elongated. That is, the warp threads, which initially protrude outward from the weave plane, quickly stretch due to the tension and heat during the heat treatment, and thus become wedged into the interior of the fabric.Final Generally speaking, the floating parts of the warp yarns and the floating parts of the paper layer of the first and second wefts all form one plane.On the running side, the weft yarns (5
) strongly lifts the warp (6), resulting in the lower layer (
The outer side of 2), ie, the traveling part II of the paper net, is only the floating part due to the weft (5).

Therefore, on the running side, the gap between the weft and warp is 8.5/1 (
There is a height difference of 10 fl. Therefore, the weft material is 8.
571 (10711J) The warp yarns do not come into any contact with the elements of the paper layer forming section of the paper machine until they are worn out.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of a paper screen according to the invention, in this case an upper shaft channel. FIG. 2 is a plan view of the paper screen in FIG. 1. FIG. 3 is an organizational chart of the papermaking net shown in FIGS. 1 and 2. FIGS. 4 to 6 are similar to FIGS. 1 to 3, respectively, but in this case they are for a twin-shaft paper screen. 7 and 8 are a longitudinal section and a plan view of the running side of a paper screen in a further embodiment according to the invention, in which one of the warp threads is interwoven only with the upper layer. FIGS. 9 and 1○ are drawings for a paper screen similar to FIGS. 7 and 8, but in this case with a multi-axis structure. FIG. 11 is a plan view of a paper net having a mirror-symmetrical structure. FIG. 12 is a longitudinal cross-sectional view of a paper screen with three weft layers. (IJ... Upper layer (2)... Lower layer (3), (3), (4), (F5+... Weft (
6)...Warp (7), (8), (9)...Linear (101...
...Paper Patent Applicant/V-Man Wangner Gesellschaftmit Beschrenktel Hafrangland Kompany Komanjit Gesellschaft Agent Kenbu Arata (1 other person) FIG, 2

Claims (4)

[Claims] (1) Weft (3), (4), (5) are upper layer and lower layer (1)
, (2) or (21), (22) and are interwoven with the warp (6) or (16), respectively, in which case the number of wefts in the upper layer (1) or 21 is the same as that of the lower layer ( 2) or twice the number of wefts in (22),
Each warp (6) or original upper layer (1
) or (21), and the wefts (3) and (4) of these upper layers (1) and (21) are interwoven twice.
), (4) and the warp (6) or (16) are twilled (7), (
The first weft yarn (3 ) is the paper (10
), and this part is supported by the saddle of the twill component formed by one warp (6) or (16); and second wefts (4) of the upper layer (1) or (21), which are arranged alternately with the first wefts (3), form a twilled component (8) in contact with the paper surface (10). , this part consists of two warp threads (1) and (16), one that rises from the adjacent weaving structure to the plane of the paper (10) and one that descends from the plane of the paper (10) into the woven fabric. A paper net characterized by being twisted and supported. (2) The warp (6) is connected to the weft (3), (4) of the upper layer (1) or (21) in front and behind the saddle of each twill component.
) passing directly over the two warp threads (6);
Claim (1) is characterized in that the weft threads (3) and (4) of the upper layer (1) or (21) run in a staggered manner in the longitudinal direction from the warp threads next to each other every six. The papermaking net described. (3) The warp (16) is only partially connected to the weft (3) of the upper layer (1).
), (4), and the remaining part of the warp (6) is interwoven with the weft (5) of the lower layer (2) once or twice. )
or (2). (4) Another layer (23) of weft yarns (25) is provided further below, and this layer is connected to the weft yarns (5) of the middle layer (22) under the upper layer (21) by the warp yarns (27). ) The paper net according to any one of claims (1) to (3).