JPH0446549Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a monofilament with a twin-shaped cross section that is used as yarn for fishing nets.

It has been well known that synthetic resin monofilaments are used as raw threads and these monofilaments are woven to produce fishing nets. This monofilament is generally produced by being pulled out from an extrusion die and stretched so that it has a perfectly circular cross section. However, it is difficult to stretch this monofilament with a perfect circular cross section (hereinafter simply referred to as a perfect circular monofilament) while maintaining the perfect circular shape, and fishing nets have not been manufactured using this monofilament with a perfect circular cross section. In this case, the disadvantage was that the knots of the fishing net were easily misaligned.

For this reason, when knitting perfect circular monofilament into a net shape, the knots that form the stitches were made into double knots, but this also resulted in misalignment of the stitches, so recently a triple stitch pattern was devised. However, the triple eye shape requires the installation of new machinery and equipment to manufacture it, which poses the problem of high equipment costs.

It is also known to manufacture fishing nets by making the monofilament have an elliptical cross section and using this monofilament as a yarn, but the conventional monofilament with an oval cross section (hereinafter simply referred to as elliptical monofilament) There was a problem with the diffused reflection, which caused fish to sense it and not to approach the fishing net.

The present invention is intended to eliminate the above-mentioned drawbacks. By making the cross-sectional shape of the monofilament a specific shape, when a fishing net is manufactured using this monofilament, the knots are less likely to be misaligned, and the net itself To provide a monofilament for fishing nets that has improved strength and does not reflect diffusely, making it possible to obtain fishing nets that are difficult to detect by fish.

In other words, the monofilament for fishing nets of the present invention is
Its cross-sectional shape has a pair of troughs located approximately in the center of both sides along the long axis of the approximately elliptical cross section, that is, two circles or approximately circles with parts of them overlapping each other. As a conjoined form of twins,
The trough is characterized in that the groove forms a linear groove extending in the length direction of the monofilament on the surface of the monofilament.

The twin-shaped monofilament of the present invention does not extrude two monofilaments with circular cross sections separately and then combine them, but instead extrude them one by one from each of the many small holes provided in the nozzle of the die of the extruder. Either the cross-section is twin-shaped when it is finished, or it is later shaped into a twin-shaped cross-section by pressing, etc.

Hereinafter, the monofilament of the present invention will be explained in more detail based on the drawings.

FIG. 1 is a perspective view showing the cross-sectional shape of a conventionally used perfect circular monofilament 1. FIG. It was difficult to stretch this monofilament 1 while maintaining a perfectly circular cross section, and when it was knitted into a net shape as described above, misalignment easily occurred.

FIG. 2 is a sectional view showing a conventionally used monofilament 11 having an oval cross section. A fishing net obtained using this monofilament 11 was prone to diffuse reflection on the surface of the monofilament 11, and was easily detected by fish.

FIG. 3 is a sectional view showing an example of the monofilament of the present invention. This monofilament 21
A pair of troughs 2 are provided approximately at the center of both surfaces 21a, 21a forming a thin portion with a roughly elliptical cross section.
1b and 21b are provided, thereby forming mountain portions 21c and 21c on both surfaces 21a, and the true circular portions 21d and 21d have a twin shape in which side ends are overlapped with each other.

FIG. 4 is a sectional view showing another example of the monofilament of the present invention. This monofilament 31
This is an example in which the pair of troughs are made deeper, and the cross section is twin-shaped with two perfectly circular portions 31a and 31a adjacent to each other on their side surfaces. The valley provided in the monofilament of the present invention does not necessarily have to be approximately in the center of the ellipse, but as in the example shown in FIG. 5, one side is a large circle 41a and the other side is a small circle 41.
It is also possible to have a cross-sectional shape of b. Furthermore, the sixth
As shown in the figure, one side may be a perfect circle 51a and the other side may be an elliptical cross-section 51b.

The monofilament of this invention uses synthetic resin,
Extrude into the specified shape from an extrusion die according to the usual method,
Obtained by stretching if necessary.

The monofilament of the present invention has a twin-shaped cross section, which makes it easy to draw, and the twin-shaped monofilament has the advantage of about 10% higher tensile strength than a monofilament with a perfectly round cross section of the same dimensions. have Moreover, since the twin-shaped monofilament has a thin section and a thick section in its cross section, it is more flexible when woven into a net shape than a perfectly circular monofilament.

In addition, when fishing nets are knitted using monofilament with a twin cross section, the knots of the fishing nets are well tightened, and no misalignment occurs, and the knitting machine used previously can be used as is. Economically advantageous.

The elliptical monofilament was easily detected by fish due to its diffuse reflection, but in the present invention, a pair of valleys are provided on opposing surfaces of the elliptical cross section, that is, a pair of grooves are provided along the sides of the monofilament. This effectively prevents diffused reflection and increases the amount of fish caught.

As shown in FIG. 7, the fishing net knitted using the monofilament of the present invention has two peaks 21c and 21 of the filament 21 (or 31) for the fish body A.
Since the filaments are physically in contact with each other and the filament does not turn over, it has the advantage that once a fish is caught, it is difficult to remove. It is said that about half of the fish are lost once they are caught in the net, and from this point of view, the amount of fish caught is expected to increase.

As is clear from the above description, the monofilament with a twin cross section according to the present invention has the advantage that it is easy to manufacture, has high strength, and that the knotted portions are strongly tightened when knitted into a net. Therefore, the fishing net obtained using this monofilament has the advantage of being excellent in strength and durability, and does not allow fish to escape once caught, and does not reflect diffusely, greatly increasing the amount of fish caught.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a conventional perfect circular monofilament, FIG. 2 is a sectional view showing a conventional elliptical monofilament, and FIG. Figure 4, 5th
6 and 6 are cross-sectional views showing another example of the twin-shaped monofilament of the present invention, and FIG. 7 is a schematic cross-sectional view showing a state in which a fish is caught in a fishing net manufactured using the monofilament of the present invention. represent 1... Perfect circular monofilament, 11... Oval monofilament, 21, 31... Monofilament of the present invention.

Claims (1)

[Scope of utility model registration request] The monofilament is a monofilament having a substantially elliptical cross-sectional shape with a pair of valleys on both sides of the long axis of the ellipse. A monofilament having a shape in which they are overlapped and bonded together, and the valley portions form linear grooves extending in the length direction of the monofilament on the surface of the monofilament. Twin-shaped monofilament for fishing nets.