JP2781357B2 - Dryer canvas fittings for papermaking - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a joint for a papermaking dryer canvas and, more particularly, to a joint in which yarn-up and cut-off portions at the folded warp ends of a joining loop forming warp and a leading weft holding warp are dispersedly arranged at both ends of the canvas. .

[0002]

2. Description of the Related Art Although various means for joining a papermaking dryer canvas endlessly have been proposed, generally, weft yarns at both ends of a woven canvas are removed over a predetermined length to form a comb. A warp is formed, the warp is folded back toward the canvas body, and the folded end is sewn into the woven structure of the canvas body to form a joining loop. A method is employed in which the loops are interconnected by meshing each other and inserting a core wire inside the common hole of the joining loop.

Recently, in order to improve the surface smoothness of a papermaking dryer canvas, a papermaking dryer canvas using a flat cross-section monofilament yarn as a warp as disclosed in Japanese Patent Publication No. 58-28398 has been provided. It is becoming.

A joint for a papermaking dryer canvas using a flat filament monofilament yarn as a warp is formed by the same method as described above, but because of the use of a flat cross section monofilament yarn, the joint side (PS) is used. In a weave structure in which the warp and the machine side (BS) are asymmetric, it is necessary to twist the warp by 180 ° in order to smoothly bind the joining loop forming warp. When the warp yarn is twisted by 180 °, the portion of the flat yarn that stands in the vertical direction in the cross section is pressed to push the leading end weft of the paper contact side (PS) toward the paper contact side (PS). For this reason, the leading end weft and the joining loop bulge and protrude toward the paper contact surface side (PS), so that the surface smoothness of the joint portion cannot be obtained. As a result, a paper mark may be generated on paper that requires delicate paper surface, such as high-quality paper or thin paper.

Recently, a single-run canvas system,
As improvements to the single-run system, for example, the Bell-run system (a trademark of Beloit, USA), the speeding up of paper machines is being developed more and more. In addition, the smoothness of the surface is strictly required. The twist of the joining loop should be changed to the contact side (PS)
, The effect of torsion is inevitable,
In S), the surface smoothness is impaired, and it is not possible to sufficiently cope with the speeding up of the paper machine. Further, the joint portion is worn out, and the life is shortened.

As shown in FIG. 8, if the twisted portion (5) of the joining loop (4) is provided not on the paper contact side (PS) but on the opposite machine side (BS) (Invention Association, July 1992) The public technical bulletin issued on the 1st, see the official technical report No. 92-15467), and the influence of the twisted portion (5) does not appear on the paper contact side (PS). In such a joint, a part of the warp (1) is folded back at the end of the canvas body to form a joining loop (4), and the remaining warp (1) involves the wefts (2) and (2) at the tip. The joint is formed by folding back and holding the leading end wefts (2) and (2), and inserting the core wires (3) and (3) into the joining loop (4).

In this case, when the thread ends of the folded warp (1) are stitched between the warp rows on the canvas body side, both thread ends are cut at the meeting point of the warp on the canvas body side and the folded warp. There is something that matches. For example, Japanese Utility Model Laid-Open No. 54-181103 discloses FIG.
As shown in the figure, the folded wrapped warp (a5) and the cut warp (a5 ′) on the canvas body side are combined with the machine side (B).
The yarn is raised on the weft (n) of S) and cut at a position slightly depressed from the surface of the canvas body. However, in this case, the cut yarn ends play because there is no presser, so that the loop forming sewn warp (a5) and the cut warp (a5 ′) are easily loosened by tension or the like during the papermaking operation.

Therefore, an improved yarn raising and cutting structure shown in FIG. 9B has been proposed. In this improved type, the stitched warp (a5) is not cut on the weft (n), but is entangled with the weft (m) on the farther side by one weft when viewed from the joining loop side. The warp (a5) and the warp (a5 ') on the canvas body side are cut so as to partially overlap each other. However, in this improved type, the cut warp (a5 ') from the canvas body side only intersects with the stitched warp (a5), so that the presser is weak, and the cut warp due to tension, impact, etc. during the papermaking operation. (A5 ') might rise to the paper contact side (PS).

Therefore, as shown in FIG. 10, the warp (1) to be cut on the canvas body side is further structured from the weft (8) to the weft (7) closer to the joining loop, and the machine side (B)
S) and then cut, and both the stitched warp and the cut warp are extra-textured with the wefts (6) and (7) in the longitudinal direction of the canvas to prevent slack by frictional force and woven crimp, and A method has been proposed for sufficiently preventing the emergence of PS (PS) (Publication No. 90-2860, published by the Japan Institute of Invention and Innovation on February 20, 1990).

When this method is applied to a dryer canvas using a flat warp having a long crimp weave on the machine side (BS), the yarn is pulled up on the machine side (BS) as shown in FIG.
At this time, both yarns to be butted before and after the yarn raising position are vertically overlapped in parallel. In the configuration shown in FIG.
Warp (a5) sewn because the holding by the weft (8) is effective
And the warp (a5 ′) can be sufficiently prevented from floating on the paper contact side (PS).

[0011]

However, when the weaving density of the warp exceeds 100 (%) in such a binding structure, the binding warp (a5) and the cut warp (a5 ') are originally provided at the yarn raising portion. ) Are closely overlapped with each other, so that the warp yarns push out to the machine side (BS) by pressing each other, and also break into another warp row adjacent in the width direction, thereby deteriorating the surface property of the canvas. There was a problem of uniformity.

[0012] Further, at the point where the staple warp (a5) and the cut warp (a5 ') are butted and each yarn end is raised, the warps are raised at the same position so as to be aligned on a straight line in the width direction of the canvas. Then, a large number of warp ends are arranged in the canvas width direction at the yarn raising location. For this reason, when compared with other places where no yarn is raised, the surface is inevitably different in the width direction at that location, and a paper mark is generated at the location where the yarn is raised during papermaking.

An object of the present invention is to provide a dryer canvas joint in which a staple warp and a cut warp are not loosened and have a uniform surface property.

[0014]

According to the present invention, in order to solve the above-mentioned problems, the wefts at both ends of a papermaking dryer canvas having a flat warp yarn and a long crimp weave at least on the machine side are used. A part of the warp yarns that have been removed and thus interdigitated are folded back to the main body of the canvas as a joining loop forming warp and sewn between warp rows, thereby forming rows of joining loops at both ends of the canvas. At the same time, the remainder of the warp extending in the interdigital shape is folded back toward the canvas body side while being wound with the leading end wefts at both ends of the canvas as a leading weft holding warp, and sewn between the warp rows, and at both ends of the canvas. In a joint of a papermaking dryer canvas in which rows of joining loops are engaged with each other and a core wire is inserted into a common hole of the joining loop,

The folded warp ends of the joining loop forming warp and the leading end weft holding warp, and the warp headed from the canvas main body side to the canvas end are interposed between two adjacent wefts on the machine side. After crossing while facing the contact surface side, the adjacent wefts were picked up and cut from both front and rear sides, and the pick-up cut points of each warp row were dispersed and arranged within a predetermined range in the longitudinal direction of the canvas.

In this dispersion arrangement, for example, the weaving structure of the warp of the canvas main body is repeated in units of n yarns. The yarn raising cuts 2 are distributed and arranged in the longitudinal direction of the canvas within a predetermined length range of both ends of the canvas main body.

[0017]

[Function] By distributing the yarn raising cut points,
The effect of the yarn raising on the uniformity of the canvas surface is diffused, thereby eliminating the occurrence of paper marks.

[0018]

An embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows a joint portion of a dryer canvas (20) according to the present invention. The structure of the canvas (20), the specifications of the warp and weft used, and the weaving density are as shown in FIG. 2, and the machine side (BS) is a long crimp weave with more than two wefts.

In order to form a joint, first, weft yarns at both ends of a canvas are removed over a predetermined length (by a predetermined number) to produce a comb-shaped warp. Next, of the flat yarns (21) and (22) constituting the canvas, the warp (21) is formed as a loop forming warp (21) to form a loop (30).
Twist 180 degrees at the reversing part (50) on the machine side (BS) to sew it into the warp row of the canvas body. New joint end wefts (41), (42), (44), and (45) are sewn into the joint end. The other warp (22) is used as a weft presser warp (22), and is wound on the machine side (BS) while winding the leading end wefts (41) and (43). Spell.

The warps (21), (2) constituting the canvas
For 2), a flat yarn of a polyester monofilament yarn having a short side (vertical side) of 0.28 mm and a long side (horizontal side) of 0.56 mm is used. Twisted yarn (ACF 6s)
/ 4) and the machine side (BS) weft (24) and the joint end weft (45) have a polyester monofilament yarn having a diameter of 0.6 mm (TM060).
Is displayed).

As the weft 42 at the joint end contacting surface side (PS), a yarn obtained by resin-processing a twisted yarn obtained by twisting three acrylic spun yarns with epoxy resin is used. Further, a twisted yarn obtained by twisting five tenth yarns of polyester spun yarn was used as the leading end weft (41) on the joint end contact surface side (PS). As a result, the leading end weft (41) becomes the joint end weft (4).
2) It is slightly thinner, and the leading end weft (41) is prevented from protruding the warp (22) toward the paper contact side (PS).

The end weft (4) on the machine side (BS) of the joint end
3) has the same specifications as the joint end weft (42) on the paper contact side (PS), and the leading end weft (43) is slightly thinner than the wefts (44) and (45). This is to prevent the loop (30) from protruding toward the machine surface (BS).

The weft (44) adjacent to the tip weft (43) among the end wefts on the machine side (BS) is a 2500 denier polyester multifilament yarn and a 210 denier nylon multifilament yarn. Three twisted yarns were twisted, and four twisted yarns were used.

As shown in detail in FIG. 3, the warp-up portion of the warp is composed of two adjacent wefts (a1) closer to the joining loop and a cut warp (a2) closer to the main body of the canvas. l ₁ ) and (l ₂ ) cross each other in an X-shape while facing the paper contact side (PS), and then the adjacent wefts (l ₁ ) and (l ₂ )
₂ ) The yarn is cut from both front and rear sides. Specifically, warp (a1) is fit under the weft mechanical plane side (BS) of the canvas main body of the joining loop side of the weft _{(l 2) (l 1)} , then the machine side of the (BS) Lee The yarn is raised to the position. The warp (a2) the machine side of the weft (l ₁₎ (B
S), go under the weft (2) and then on the machine side (BS)
The yarn is raised to the position of b. As described above, the sewn warp (a1) and the cut warp (a2) are not overlapped with each other in a parallel manner but intersected with each other.
(A2) There is little mutual pressing, and there is no jumping out of the warp at the yarn raising portion and no interruption to other adjacent warp rows in the canvas width direction, so that the surface of the canvas is uniform.

In addition, according to the present invention, since the yarn cutting sections are dispersed as described below, the surface of the canvas becomes more uniform. FIGS. 4 to 7 show the weaving state of each warp in a so-called eight-repeater drier canvas in which eight warps constitute a repeating unit of a weave structure in a range of two repeats. As shown in the drawing, 16 warps (a1) to (a16) for two repeats are distributed at eight positions in the longitudinal direction of the canvas body.
The yarn is being raised. (I) of (A) of each figure shows the outward path and the folded part of the warp forming the loop for joining, and (I) of (A)
I) shows a crossing-up yarn cutting position between the return path of the joining loop forming warp and the warp on the canvas body side. As can be understood from FIGS. 4 to 7, the yarn cutting portions are dispersed in the longitudinal direction of the canvas main body so that they are not arranged linearly in the canvas width direction, so that the surface of the canvas becomes uniform.

A woven fabric using the dryer canvas joint of the present invention may be used as a base fabric, and a web may be laminated on one or both sides of the base fabric and needling to prepare a needle canvas for papermaking. it can.

[0028]

According to the present invention, a flat yarn is used as a warp,
In a dryer canvas having a long crimp weave on the machine side, a sewn warp and a cut warp are intersected between two adjacent wefts without overlapping in parallel, and then the yarn is raised, and the two wefts are used. A presser is used at the yarn raising end to prevent the sewn warp and the cut warp from loosening due to tension during papermaking operation, and the yarn raising and cutting locations are dispersed and arranged in the longitudinal direction of the canvas. In combination with this, the surface properties at the joint end of the dryer canvas can be made uniform, and the occurrence of paper marks can be prevented.

[Brief description of the drawings]

FIG. 1 is a side view of a joint of a dryer canvas of the present invention.

FIG. 2 is a diagram showing specifications of a canvas.

FIG. 3 is an enlarged side view of a yarn raising portion.

FIG. 4A is a side view of the first and second warp rows, and FIG.
Is a side view of the third and fourth warp rows.

FIG. 5A is a side view of fifth and sixth warp rows, and FIG.
Is a side view of the seventh and eighth warp rows.

FIG. 6 (A) is a side view of ninth and tenth warp rows,
(B) is a side view of the eleventh and twelfth warp rows.

FIG. 7A is a side view of the thirteenth and fourteenth warp rows,
(B) is a side view of the fifteenth and sixteenth warp rows.

FIG. 8 is a side view of a conventional joint end.

9A and 9B are side views of a conventional joint end.

FIG. 10 is a side view of a conventional joint end.

FIG. 11 is a side view of a conventional joint end.

[Explanation of symbols]

 (20) Dryer canvas (21) (22) Warp (30) Loop (41) (43) Tip weft (42) (44) (45) Joint end weft (50) (51) Reversing part

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) D21F 7/10 D21F 7/08

Claims (2)

(57) [Claims] 1. A weft at both ends of a papermaking dryer canvas having a flat warp and a long crimp weave on at least the machine side is removed over a predetermined length. The portion is folded back to the canvas body side as a joining loop forming warp and sewn between warp rows, thereby forming a row of joining loops at both ends of the canvas, and the remaining portion of the warp extending in the IDT shape Is folded back to the canvas body side while winding the leading end weft at both ends of the canvas as a leading weft holding warp, and sewn between warp rows, and the rows of joining loops at both ends of the canvas are engaged with each other, and the joining loop is formed. In a joint of a papermaking dryer canvas in which a core wire is inserted into a common hole, each folded warp of the joining loop forming warp and the leading end weft holding warp. And a warp heading from the canvas body side to the canvas end portion, crossing the two wefts adjacent to each other on the machine side while facing the paper contact side, and then raising the yarn from both front and rear sides of the adjacent weft. A joint for a papermaking dryer canvas, characterized in that the joints are cut and cut, and the yarn raising cut points of each warp row are dispersed and arranged within a predetermined range in the longitudinal direction of the canvas. 2. The papermaking dryer canvas in which the weaving structure of the warp of the canvas body is repeated in units of n yarns, and thus the yarn raising cut section is formed at n / 2 positions, 2. The joint for a papermaking dryer canvas according to claim 1, wherein the joints are distributed in the longitudinal direction of the canvas within a predetermined length range of both ends of the canvas main body.