JPS6328240Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a joint for a dryer canvas for paper manufacturing, and more particularly to an improved joint for a dryer canvas in which the paper-contacting surface side is woven into a twill weave with multiple weaves of double weave or higher.

B. Prior Art A dryer canvas with a diagonal weave on its contact surface has warp threads crossing multiple weft threads to form a floating weave. FIG. 1 is a longitudinal sectional view of the end of a dryer canvas which is woven into a double weave and whose contact surface is a 2/2 broken diagonal weave. In this case, the weft 1 on the contact surface P has a structure that exceeds the two wefts 2, 2. Therefore, the tops of the knuckles of the warp yarns 1 do not protrude, and the surface P in contact with the paper is highly smooth, improving the paper quality without roughening the paper surface, and preventing the adhesion of dirt substances such as foreign matter in the paper web or sizing liquid. prevent.

Conversely, the warp threads 1 cross over the weft threads 2' one by one on the mechanical plane Q, contributing to maintaining the stability of the canvas.

As described above, the dryer canvas has an excellent paper-contacting surface, and the joint that joins both ends of the dryer canvas must also have similar characteristics.

Therefore, a joint as shown in FIG. 1 has been conventionally used. In this joint, a part of the warp yarns constituting the canvas is used as a loop-forming warp yarn 3, and a loop 5 is formed by extending from the end of the canvas. The warp threads 3 are then woven into the canvas body with the same texture. A part of the warp other than this is similarly extended from the edge of the canvas as the weft presser warp 4, folded back along the frontmost weft 6 of the paper contact surface and the frontmost weft 7 of the machine surface, and folded into the main body, so that the wefts 6 and 7 are Stop it from fraying. The loops 5 at both ends of the canvas thus created are combined with each other, and the core wire 8 is inserted through the common hole to form an endless shape. Since this type of joint forms a loop with the warp threads of the main body, the surface smoothness of the joint part is similar to that of the main body part, and the required performance can be provided to some extent.

However, perfect smoothness was not achieved, and the loops in particular had a strong tendency to protrude from the contact surface. Although this is exaggerated in FIG. 1, the loops 5 were smooth up to the weft presser warp 4, but the loops 5 were protruding. This is because the texture is asymmetric between the contact surface P and the mechanical surface Q, resulting in unbalanced crimp of the warp threads. This protrusion of the loops may cause marks on paper that requires delicate paper texture, such as high-quality paper and thin paper. In order to prevent this, a method of forming the loop 5 smaller was attempted, but it became difficult to insert the core wire, and the work required a lot of time.As a result, the paper machine was stopped for a long time and the production amount was reduced.

In addition, the most advanced weft yarns 6 on the paper contact surface and the most advanced weft yarns 7 on the machine surface are prevented from fraying by the weft holding warp yarns 4, but the binding force in the width direction is weak, and in the case of monofilament yarns, they sometimes come loose.

(b) Purpose of the invention In view of the drawbacks of the prior art, the inventor of the present invention conducted extensive research and found that the most advanced weft yarn 6 on the contacting surface lifts the loop and protrudes toward the contacting surface, and has proceeded with improvements. The purpose is to provide a joint with excellent smoothness even when the contact surface is a canvas with a diagonal structure.

C. Structure of the idea FIG. 2 shows an embodiment of the joint according to the present invention.

First, as in the conventional case, a part of the warp forming the canvas body is used as the loop forming warp 13, and a part is used as the weft holding warp 14. These two warps 13, 14
is extended from the edge of the canvas, and the loop-forming warp 13
is folded back to form a loop 15 and stitched into the main body. On the other hand, the weft holding warp 14 is the tip weft 1
It is folded back so as to surround 7 and 19, and is inserted into the main body. The joint according to the present invention differs greatly from the conventional one by excluding the leading edge weft 6 in FIG.
There is no weft within the loop 15.
By excluding the weft yarn 6, the loop 15 is
At the same time as moving toward the Q' side, the present inventor found that the weft holding warp 14 is lifted toward the paper contact surface P' side. All of these are caused by the unbalanced crimp action of the warp threads, as described above.

In other words, the most advanced weft yarn 6 has limited the positional relationship between the loop 5 and the weft presser warp yarn 4, but when the weft yarn 6 is removed, both return to their original positions due to crimping, and as a result, the level difference is alleviated. However, it is still slightly raised compared to the canvas itself. In order to further improve this and make the contact surface P′ even smoother, the cross-sectional area of the tip weft 19 on the contact surface side was increased, and the portion 2 where the loop-forming warp 13 appeared on the contact surface
Add some bulge to 0. The joint created in this manner forms a surface that gradually rises from the canvas body toward the loop 15, as shown by the two-dot chain line 21.

In the embodiment shown in FIG. 2, the warp yarns 13 and 14 and the weft yarns 12 and 12' are made of monofilament yarn, multifilament yarn, spun yarn, a combination of these yarns, or resin-treated yarn with a diameter of 0.3 to 0.8 mm. The core wire 18 is generally a monofilament yarn with a diameter of 0.4 to 1.0 mm or a multifilament yarn treated with a resin. In this case, in order to make the cross-sectional area of the tip weft 19 on the contact surface larger than that of the other wefts 12 and 12', the diameter is
Do you use yarn with a circular cross section of about 0.4 to 1.0 mm, or twist yarn such as monofilament yarn or multifilament yarn, or use yarn with a flat cross section as shown in Figure 3, or multiple yarns as shown in Figure 4? Use a parallel version of Again, the average diameter is 0.4-1.0
Approximately mm.

As a specific example, a double-weave dryer canvas with a joint loop shown in Figure 2 is made of polyester monofilament yarn with a diameter of 0.5 mm for the warp and weft, and a polyester monofilament yarn of 0.6 mm in diameter for the tip weft on the side facing the paper. or similar diameter 0.24
Use mm/2/2 twisted yarn.

Further, in order to prevent the mechanical surface tip weft 17 from slipping out, twisted monofilament yarns, multifilament yarns, or spun yarns are used.

D. Effects In the joint according to the present invention, the contact surface slopes smoothly from the main body toward the loop, and there is no protrusion. Therefore, when in use, the paper contact surface is smooth and the sheet is not pressed too hard, so that it does not cause any negative effects such as marks. Furthermore, since the size of the loop is the same as before, there is no problem in inserting the core wire.

As described above, the joint according to the present invention is a good joint in which the contact surface does not impair the excellent characteristics of the canvas having a diagonal structure.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing a conventional joint, FIG. 2 is a longitudinal sectional view of a joint according to the present invention, and FIGS. 3 and 4 are sectional views of a weft at the end of the paper contact surface. 1... warp, 2, 2', 12, 12'... weft, 3,
13'...Loop-forming warp, 4, 14...Weft holding warp, 5,15...Loop, 6...Cutting edge weft, 7,
17... Machine surface tip weft, 8, 18... Core line, 19...
Paper-contacting surface tip weft, P, P'...paper-contacting surface, Q, Q'...mechanical surface.

Claims (1)

[Scope of utility model registration request] In a joint where a loop is formed by a part of the warp of a dryer canvas which is a multiple weave of double weave or higher, and the texture on the contact surface side is woven with a diagonal weave, there is no weft within the loop, and there is no weft in the loop. A dryer canvas joint characterized in that the cross-sectional area of the tip weft on the paper side is 1.4 to 2.0 times larger than the cross-sectional area of other weft yarns.