EP1780371A1

EP1780371A1 - Insect-proof net for screen door and method of manufacturing the same

Info

Publication number: EP1780371A1
Application number: EP04746462A
Authority: EP
Inventors: Mitsuhiko SEIKI HANBAI CO. LTD. CHINO; Masato SEIKI HANBAI CO. LTD. MORIYA
Original assignee: Seiki Hanbai Co Ltd
Current assignee: Seiki Hanbai Co Ltd
Priority date: 2004-06-25
Filing date: 2004-06-25
Publication date: 2007-05-02
Also published as: CN1973107B; CN1973107A; JP4693776B2; JPWO2006001056A1; WO2006001056A1

Abstract

The present invention is to provide an insect net for a screen door capable of expansion/contraction in an accordion manner which is given excellent planar shape retaining performance and strength to withstand wind pressure for smooth bending action for expansion/contraction at opening/closing operation, in which a net base body (3) divided by pleats (4) and folded alternately in the opposite direction is made into a lattice structure using a core-in-sheath yarn (6) covered by a low melting resin on the circumferential face and a fiber bundle (7) bundling easily bendable synthetic resin fibers by Russell-braiding. The net base body is braided mainly of the core-in-sheath yarns so that the lateral yarns made only of the fiber bundles are arranged only between the vertical yarns at the side ends of the adjoining net base bodies, and the core-in-sheath yarns are mutually welded by heat melting of the low melting resin so as to give the planar shape retaining performance to the net base body.

Description

Technical Field

The present invention relates to an insect net for a screen door capable of expansion/contraction in an accordion manner by providing a large number of pleats and its manufacturing method.

Background Art

An insect net capable of expansion/contraction in an accordion manner by providing a large number of pleats forms a required mesh net by using filaments made of polyester fiber, polypropylene fiber and the like and by weaving a warp and a weft and then, by forming a large number of pleats with pleats in the vertical direction with heat and pressure or the like to make it capable of folding.
And this accordion type insect net capable of expansion/contraction requires planar shape retaining performance to withstand a certain degree of wind pressure in a net base constituting a plane portion between the pleats and bending flexibility required for expansion/contraction operation at opening/closing operation of the net in the pleat portion.
However, in a conventional net with pleats formed by folding a planar net equal in the vertical and lateral directions of a required mesh is alternately folded in the opposite direction with a narrow width and pleats are formed by heat treatment, the planar shape retaining performance of the net base body constituting the planar portion between the pleats is not satisfactory and therefore, in the bending flexibility of the pleat portion, it is difficult to obtain a zigzag shape forming a clean peak shape at opening/closing operation of the insect net, appearance is poor and there is difficulty in smooth folding, which is a problem.
On the other hand, the insect net given sufficient bending flexibility in the pleat portion is already known as Japanese Patent No. 3323829 . In this publicly known insect net, side ends of adjoining net base bodies are connected through a connecting yarn constituted of the other filament more easily bendable than a filament constituting the net base body, and a pleat is formed on the connecting part. But it is requested to further improve the planar shape retaining performance of the net base body to have a net for a screen door which withstands wind pressure.
In order to obtain the screen door net satisfying such demand, that is, the net which can withstand the wind pressure, the planar shape retaining performance is to be improved by means such as reinforcement of strength of the filament constituting the net base body, but the means should not generate a new defect. For example, simple increase of the thickness of the filament will increase the weight of the net or the thickness when folded, which is not preferable.
Also, it is not necessarily preferable to simply improve the vertical and horizontal planar shape retaining performance of the net base body equally, but in order to obtain the strength against the wind pressure, it is effective to improve the planar shape retaining performance in the vertical direction of the net base body. And particularly if a bending flexibility is given only between the vertical yarns of the side ends of the adjoining net base body to make it a bending position of the net, the high planar shape retaining performance in the lateral direction of the net base body might give an excessive deforming force to the portion to which a sufficient bending flexibility is applied for opening/closing of the net, which might lead to a bad influence on the durability of the net pleat portion.

Disclosure of Invention

A technical problem of the present invention is to provide an insect net for a screen door which gives strength against wind pressure to a net base body of the insect net capable of expansion/contraction in an accordion manner by making the planar shape retaining performance excellent through appropriate means and can obtain a bending operation for smooth expansion/contraction in opening/closing operation and its manufacturing method.
Another technical problem of the present invention is to provide an insect net for a screen door and its manufacturing method which can easily change the planar shape retaining performance in the vertical and horizontal directions of the net base body, since a higher planar shape retaining performance in the vertical direction of the net base body is effective to obtain strength of the insect net against wind pressure, while the higher planar shape retaining performance in the lateral direction might gives excessive deforming force to a bent portion between the adjoining net base bodies.
In order to solve the above problem, the insect net for a screen door of the present invention is a net capable of expansion/contraction in an accordion manner by folding a narrow and long net base body divided by a large number of pleat portions alternately in the opposite direction at the pleat portion, made by using at least a core-in-sheath yarn covered by a low melting resin on the circumferential face and a fiber bundle bundling easily bendable synthetic resin fibers so as to braid them into a lattice structure having a large number of vertical and lateral yarns by Russell braiding, and a part of the plurality of core-sheath structure yarn in the vertical yarns and the above fiber bundle are twined with mutual vertical yarns and reciprocated between the vertical yarns separated by a single or a plurality of rows so as to form the lateral yarn, and by that, the net base body is constructed mainly by the core-in-sheath yarn as a net braided so that the yarn is included in all the vertical yarns and all the lateral yarns. Also, the yarns are braided so that the lateral yarns made only from the above fiber bundles are arranged only between the vertical yarns at the side ends of the adjoining net base bodies, the core-in-sheath yarns are welded to each other by heat welding of the above low melting resin so as to give the shape retaining performance to the net base body.
In a preferred embodiment of the insect net for a screen door of the present invention, the yarn constituting the core of the core-in-sheath yarn is constructed to have a thickness several times larger than the synthetic resin fiber constituting the fiber bundle, and the vertical yarn is constructed so that the number of the core-in-sheath yarns is at least twice or more of the number of core-in-sheath yarns contained in the lateral yarn.
In the insect net for a screen door of the present invention, the fiber bundle twined in the mutual vertical yarns and reciprocated between them can be disposed between the vertical yarns at the side ends of the adjoining net base bodies.
Also, the manufacturing method of the insect net for a screen door of the present invention is a manufacturing method of an insect net capable of expansion/contraction in an accordion manner by folding a narrow and long net base body divided by a large number of pleat portions alternately in the opposite direction at the pleat portion, and using at least a core-in-sheath yarn covered by a low melting resin on the circumferential face and a fiber bundle bundling easily bendable synthetic resin fibers, a lattice structure having a large number of vertical yarns and lateral yarns is braided by Russell-braiding, at the braiding, a part of the plurality of core-in-sheath yarns in the vertical yarn and the fiber bundle are twined with mutual vertical yarns and reciprocated between the vertical yarns separated by a single or a plurality of rows so as to form the lateral yarn, by which the net base body is constituted as a net braided mainly of the core-in-sheath yarn so that the yarn is contained in all the vertical yarns and all the lateral yarns. Also, they are braided so that the lateral yarn made only of the fiber bundle is arranged only between the vertical yarns at the side ends of the adjoining net base bodies and then, heat treatment is given at a temperature at which the low melting resin is melted so as to mutually weld the core-in-sheath yarns to give the shape retaining performance to the net base body and then, the large number of net base bodies are folded alternately in the opposite direction between them and forced in the bent state by heat treatment.
The yarn constituting the core of the core-in-sheath yarn preferably has a thickness of several times larger than the synthetic resin fiber constituting the fiber bundle, and the vertical yarn has the number of core-in-sheath yarns more than twice of the number of core-in-sheath yarns included in the lateral yarn.
In the insect net for a screen door of the present invention having the above construction, filaments constituting the net base body are braided mainly of the core-in-sheath yarns covered by low melting resin on the circumferential face so that the yarn is included in all the vertical yarns and all the lateral yarns and the core-in-sheath yarn is mutually welded by heat melting of the low melting resin. Thus, an appropriate planar shape retaining performance can be given to the net base body according to the arrangement amount of the yarn and moreover, a change can be easily made to the planar shape retaining performance in the vertical and lateral directions of the net base body. Also, since they are braided so that the lateral yarns made only of the fiber bundles are arranged only between the vertical yarns at the side ends of the adjoining net base bodies, even if they are mutually welded by heat treatment of the low melting resin in the core-in-sheath yarn, the bending flexibility at the net pleat portion is not lost.
Moreover, since the net base body improves its planar shape retaining performance in the vertical direction, its shape retaining performance effectively works to increase the strength against the wind pressure, while with regard to the planar shape retaining performance in the lateral direction of the net base body, sufficient bending flexibility is given only between the vertical yarns at the side ends of the adjoining net base bodies so as to make them bending positions of the net and bent sharply. Thus, it is necessary to suppress concentration of excessive deforming force at the bent portion by giving a high planar shape retaining performance in the lateral direction of the net base body, and since little contribution is made to suppression of deformation against the wind pressure, it is extremely effective as an insect net that the shape retaining performance in the lateral direction in the net base body can be adjusted as appropriate so that it can be set lower than the planar shape retaining performance in the vertical direction. And by sharp bending of the bent portion between the net base bodies, the insect net can be folded in the zigzag manner forming even and clean peak shapes, by which an insect net for a screen door with excellent appearance can be obtained.

Brief Description of the Drawings

Fig. 1 is a perspective view showing an entire construction of an insect net for a screen door according to the present invention.
Fig. 2 is an enlarged front view of an essential part showing an embodiment of the insect net for a screen door according to the present invention.
Fig. 3 is a block diagram showing a braided state of fiber bundles and chain-state filaments omitting a core-in-sheath yarn in Fig. 2.

Reference Numerals

1: Insect net
3: Net base body
4: Pleat portion
6: Core-in-sheath yarn
7, 7a: Fiber bundle
8: Vertical yarn
9: Lateral yarn
10: Cain-state filament

Best Mode for Carrying Out the Invention

Fig. 1 shows an entire construction of an insect net for a screen door according to the present invention.
This insect net 1 is applied to an insect screen door opened/closed by horizontally pulling a net expanding/contracting in an accordion manner, in which it is divided by a large number of pleat portions 4, net base bodies 3 in the plane state having a narrow and long lattice structure formed by Russell-braiding' of filaments are connected at the pleat portion 4 so that a sufficient bending flexibility is provided, and by folding them alternately in the opposite direction at the pleat portion 4 to make it capable of expansion/contraction in the accordion manner. The above net base body 3 is braided so as to have a planar shape retaining performance (rigidity) to such an extent to withstand wind pressure, as will be described later.
Fig. 2 shows details of an embodiment of the insect net for a screen door according to the present invention, and the insect net 1 is braided in a lattice structure having a large number of vertical yarns 8 and lateral yarns 9 by Russell-braining using at least a core-in-sheath yarn 6 covered by a low melting resin on the circumferential face and a fiber bundle 7 bundling easily bendable synthetic resin fibers. The net base body 3 in this lattice structure can be braided with a third yarn or fiber bundle added within a scope not losing the gist of the present invention.
As the core-in-sheath yarn 6, a yarn with polyester as a core material covered by low melting modified polyester as a sheath can be used, for example, and a yarn with a higher melting resin than the sheath portion constituting the core material having a thickness of several times larger than that of the synthetic resin fiber constituting the fiber bundle 7 is used.
Also, as the synthetic resin fiber constituting the fiber bundle 7, easily bendable fiber such as polyester fiber, polypropylene fiber and the like are bundled for use.
The net base body 3 is constituted as a net braided mainly of the core-in-sheath yarn 6 so that the yarn 6 is included in all the vertical yarns 8 and all the lateral yarns 9, and the vertical yarn 8 includes a filament 10 obtained by braiding the core-in-sheath yarn 6 in a chain state and is braided so that at least the number of core-in-sheath yarn 6 in the vertical yarn 8 is twice or more, preferably several times or more of the number of core-in-sheath yarns 6 included in the lateral yarns 9 including the core-in-sheath yarns 6 constituting the chain-state filament 10. And braiding is carried out so that the lateral yarns 9 made only of the fiber bundles 7 are arranged only between the vertical yarns 8 at the side ends of the adjoining net base bodies 3, by which the net base bodies 3 are connected only by the fiber bundle 7 at the pleat portion 4.
When described in more detail, the net base body 3 is braided as shown in Fig. 2, that the chain-state filament 10 of the core-in-sheath yarn 6 included in the vertical yarn 8 is twined with another core-in-sheath yarn 6 (shown by a bold line in Fig. 2) and the fiber bundle 7 (shown by a thin line in Fig. 2) and a part of those core-in-sheath yarn 6 and the fiber bundle 7 are twined with mutual vertical yarns 8 and reciprocated between the vertical yarns 8 separated by a single or a plurality of rows, or between the vertical yarns 8 separated by two rows in the illustrated example so as to form the lateral yarn 9 and at that time, the lateral yarn 9 made only of the fiber bundle 7 is arranged between the vertical yarns 8 at the side ends of the adjoining net base bodies 3. In this braiding, between the vertical yarns 8 at the side ends of the adjoining net base bodies 3, a fiber bundle 7a twined with mutual vertical yarns 8 and reciprocated between them can be provided. Fig. 3 shows a braided state only of the fiber bundle 7 in the organization obtained by the above-mentioned braiding.
The chain-state filament 10 may be braided in an appropriate organization and moreover, it is not necessary to make that completely different from the core-in-sheath yarn 6 twined with that but may be tangled with the core-in-sheath yarn 6 as appropriate.
The lateral yarn 9 in the insect net obtained by the above braiding is, as can be seen from Fig. 2, formed by the core-in-sheath yarn 6 and the fiber bundle 7 twined with the vertical yarn 8 with a constant pitch and reciprocated between the vertical yarns 8 separated by a single or a plurality of rows (2 to 3 rows, for example), and thus, the strength of the lateral yarn 9 with respect to the vertical yarn 8 can be set by how many rows to be separated between the vertical yarns 8 between which the core-in-sheath yarn 6 and the fiber bundle 7 twined with each vertical yarn 8 as shown in the figure are reciprocated or by the number of yarns or fibers constituting the core-in-sheath yarn 6 or the fiber bundles 7 set appropriately. The strength can be also selected easily such that the shape retaining performance at a portion close to the pleat portion 4 is lowered to some degree by partially changing the number of core-in-sheath yarns 6 or the number of fibers in the fiber bundle 7 in the lateral yarn 9.
Also, in the conventional insect net, when Russell-braiding is used, braiding usually progresses in the direction of the lateral yarn 9, that is, in the direction crossing the pleat portion 4. In this case, the vertical length of the insect net is regulated by braiding width of the Russell braiding machine. Thus, when the core-in-sheath yarn 6 and the fiber bundle 7 are to be Russell-braided in the above mode, the braiding progresses in the direction of the vertical yarn 8, by which the vertical length of the insect net can be freely set, an insect screen door can be easily provided in various sizes and the screen door is given versatility.
The net base body 3 is constituted as a net braided mainly of the core-in-sheath yarn 6 so that the yarn 6 is included in all the vertical yarns 8 and all the lateral yarns 9, and the fiber bundle 7 used with core-in-sheath yarn 6 is used to set the strength of the lateral yarn 9 with respect to the vertical yarn 8 and to form the pleat portion 4 between the vertical yarns 8 at the side ends of the adjoining net base bodies 3. Therefore, the description that the net base body 3 is constituted mainly by the core-in-sheath yarn 6 should be understood in this meaning.
As mentioned above, a lattice structure having a large number of vertical yarns 8 and the lateral yarns 9 are braided by the Russell-braiding using the core-in-sheath yarn 6 and the fiber bundle 7, whereby the plane state insect net 1 is braided in which the lateral yarns 9 made of the fiber bundles 7 are arranged between the vertical yarns 8 at the side ends of the net base bodies 3 made mainly of the core-in-sheath yarns.
By giving first heat treatment at a temperature for melting the low melting resin of the core-in-sheath yarn 6 after the braiding, the sheath portions of the core-in-sheath yarn 6 are mutually welded and the planar shape retaining performance of the net base body 3 is given. At this first heat treatment stage, the adjoining net base bodies 3 given the planar shape retaining performance are connected by easily bendable fiber bundles 7, and next, the large number of net base bodies 3 are bent alternatively in the opposite direction between them, and second heat treatment is carried out to force portions between the net base bodies 3 in the bent state, that is, the pleat portion 4 is formed.
The insect net for a screen door having the above construction is constituted as a net in which filaments constituting the net base body 3 are braided mainly of the core-in-sheath yarns 6 covered by the low melting resin on the circumferential face so that the yarn is included in all the vertical yarns and all the lateral yarns, and the core-in-sheath yarns 6 are mutually welded by heat melting of the low melting resin, and an appropriate planar shape retaining performance can be given to the net base body 3 according to the arranged amount of the yarn 6. Moreover, according to the above-mentioned Russell-braiding, the planar shape retaining performance in the vertical and horizontal directions of the net base body 3 can be easily changed by the number of core-in-sheath yarns 6 or the amount of the fiber bundles 7 to be arranged as the lateral yarn 9. Also, since the braiding is made so that the lateral yarns 6 made only of the fiber bundles 7 are arranged only between the vertical yarns 8 at the side ends of the adjoining net base bodies 3, even if they are mutually welded by heat treatment of the low melting resin in the core-in-sheath yarn 6, the bending flexibility of the pleat portion 4 of the net is not lost.
Moreover, since the net base body 3 has its planar shape retaining performance improved in the vertical direction, its shape retaining performance effectively acts to increase the strength against wind pressure.
On the other hand, with regard to the planar shape retaining performance in the lateral direction of the net base body 3, since sufficient bending flexibility is given only between the vertical yarns 8 at the side ends of the adjoining net base bodies 3 so that the portion is bent sharply as the net bending position, it is necessary to suppress concentration of excessive deforming force at the bent portion by giving a high planar shape retaining performance in the lateral direction of the net base body 3. And also, since the planar shape retaining performance in the lateral direction has little contribution to the suppression of deformation against wind pressure, it is extremely effective as an insect net that the lateral shape retaining performance in the net base body 3 can be adjusted as appropriate and braiding is made so that its planar shape retaining performance can be set lower than that in the vertical direction. And by sharp bending at the bent portion between the net base bodies 3, the insect net can be folded in the zigzag manner to form an even and clean peak shape, by which an insect net for a screen door with excellent appearance can be obtained.

Claims

An insect net for a screen door capable of expansion/contraction in an accordion manner by folding a narrow and long net base body divided by a large number of pleats alternately in the opposite direction at the pleat portion,
made by using at least a core-in-sheath yarn covered by a low melting resin on the circumferential face and a fiber bundle bundling easily bendable synthetic resin fibers so as to braid them into a lattice structure having a large number of vertical and lateral yarns by Russell braiding,
a part of the plurality of core-sheath structure yarn in the vertical yarns and the fiber bundle are twined with mutual vertical yarns and reciprocated between the vertical yarns separated by a single or a plurality of rows so as to form the lateral yarn,
by that, the net base body is constructed as a net braided mainly of the core-in-sheath yarn so that the yarn is included in all the vertical yarns and all the lateral yarns, and the yarns are braided so that the lateral yarns made only from the above fiber bundles are arranged only between the vertical yarns at the side ends of the adjoining net base bodies, and
the core-in-sheath yarns are welded to each other by heat welding of the low melting resin so as to give the shape retaining performance to the net base body.
The insect net for a screen door according to claim 1, wherein the yarn constituting the core of the core-in-sheath yarn has a thickness of several times of that of a synthetic resin fiber constituting the fiber bundle.
The insect net for a screen door according to claim 1 or 2, wherein at least the number of core-in-sheath yarns included in the vertical yarn is twice or more of the number of core-in-sheath yarns included in the lateral yarn.
The insect net for a screen door according to any of claims 1 to 3, wherein between the vertical yarns at the side ends of the adjoining net base bodies, there are provided the fiber bundle twined with mutual vertical yarns and reciprocated between them.
A manufacturing method of an insect net for a screen door capable of expansion/contraction in an accordion manner by folding a narrow and long net base body divided by a large number of pleats alternately in the opposite direction at the pleat portion,
wherein at least a core-in-sheath yarn covered by a low melting resin on the circumferential face and a fiber bundle bundling easily bendable synthetic resin fibers are used to braid a lattice structure having a large number of vertical yarns and lateral yarns is braided by Russell-braiding,
at the braiding, a part of the plurality of core-in-sheath yarns in the vertical yarn and the fiber bundle are twined with mutual vertical yarns and reciprocated between the vertical yarns separated by a single or a plurality of rows so as to form the lateral yarn,
by that, the net base body is constituted as a net braided mainly of the core-in-sheath yarn so that the yarn is contained in all the vertical yarns and all the lateral yarns and they are braided so that the lateral yarn made only of the fiber bundle is arranged only between the vertical yarns at the side ends of the adjoining net base bodies,
heat treatment at a temperature at which the low melting resin is melted is carried out so as to mutually weld the core-in-sheath yarns to give the shape retaining performance to the net base body and then,
the large number of net base bodies are folded alternately in the opposite direction between them and forced in the bent state by heat treatment.
The insect net for a screen door according to claim 6, wherein the yarn constituting the core of the core-in-sheath yarn has a thickness of several times larger than that of the synthetic resin fiber constituting the fiber bundle in the braiding.
The manufacturing method of an insect net for a screen door according to claim 5 or 6, wherein the vertical yarn has the number of core-in-sheath yarns at least twice or more of the number of core-in-sheath yarns included in the lateral yarn in the braiding.