JP7622948B2 - rope - Google Patents

Description

The present invention relates to ropes.

For example, there is a rope described in Patent Document 1. This rope is made by twisting together three strands, each of which has a core portion formed by twisting together multiple core yarns and a skin portion formed by arranging multiple skin yarns around the core portion, and the core yarn is made by twisting together multiple polyethylene monofilaments.

Japanese Utility Model Publication No. 63-15351

However, in the rope described in Patent Document 1, the core yarn is made of multiple polyethylene monofilaments twisted together. Therefore, for example, when the rope is pulled to apply tension to the core, permanent strain is generated in the polyethylene monofilament that serves as the core yarn, causing the rope to lose its rigidity. Incidentally, the rope described in Patent Document 1 actively uses the permanent strain to prevent a decrease in the strength of the rope. This problem is not limited to the rope described in Patent Document 1, but occurs in all ropes that have a core yarn made of monofilaments alone.

Therefore, the present invention aims to provide a rope that uses monofilaments and can prevent loss of rigidity.

The present invention is a rope constructed by twisting or combining multiple strands whose radial cross-sectional shape is substantially the same throughout the length direction, the strands being constructed by twisting or combining multiple first yarns made of monofilament yarns and second yarns made of multifilament yarns, the first yarns being more rigid than the second yarns, the second yarns having lower elongation than the first yarns, and the second yarns being disposed between the first yarns.

According to the above configuration, the second yarns, which are pushed and deformed by the first yarns, fill the gaps between the first yarns, and the first yarns are integrated through the second yarns. Therefore, the first yarns, which are arranged between the second yarns, which are less likely to stretch than the first yarn A, are prevented from moving individually. For example, when tension is applied to the rope, it is possible to prevent permanent strain caused by the stretching of the individual first yarns, and therefore to prevent the rope from becoming loose.

In addition, in the rope of the present invention, the strand may have an inner layer portion formed by twisting together the first yarn and the second yarn multiple times, and an outer layer portion that covers the inner layer portion in the circumferential direction.

According to the above configuration, the outer layer covers the inner layer, so that the outer layer can protect the inner layer.

In addition, in the rope of the present invention, the strand may have a central portion made of the second yarn and a peripheral portion that covers the central portion in the circumferential direction and is made of the first yarn and the second yarn.

According to the above configuration, since the central portion is made of the second yarn that is made of the multifilament, the central portion is less likely to bend, and since the peripheral portion is formed to cover the central portion in the circumferential direction, the peripheral portion can be formed around the central portion, making it easier to form the peripheral portion.

In addition, in the rope of the present invention, the first yarn and the second yarn may be arranged in rotational symmetry in the peripheral portion in the circumferential direction around the central portion.

According to this configuration, the first yarn and the second yarn are arranged rotationally symmetrically around the central portion in the circumferential direction, so that the circumferential strength of the strand can be made constant.

In addition, in the rope of the present invention, the peripheral portion may be configured such that the first yarns and the second yarns are arranged alternately in the circumferential direction.

According to the above configuration, the first yarns and the second yarns are arranged alternately, so that the two first yarns with the second yarn between them can be integrated.

In addition, in the rope of the present invention, the central portion may be composed of a plurality of the second yarns.

According to the above configuration, the central portion is made up of multiple multifilament yarns, which makes the central portion even less likely to bend, resulting in a rope that is less likely to bend.

Therefore, with the rope of the present invention, when tension is applied to the rope, the first yarn can be prevented from becoming loose, thereby preventing the rope from losing its rigidity.

FIG. 1 is a diagram showing a radial cross section of a rope according to an embodiment of the present invention. FIG. 2 is a diagram showing a radial cross section of a strand according to the embodiment. FIG. 3 is a view showing a radial cross section of the strand according to the embodiment, in which the radially integral portion and the circumferentially integral portion are clearly shown.

The following describes a rope 1 according to one embodiment of the present invention. This rope 1 is used, for example, as a purse seine or bottom trawl rope in fishing grounds.

In the following description, the "radial direction" refers to the direction indicating the thickness or diameter of the rope 1 or strand 2, and the "lengthwise direction" refers to the direction in which the rope 1 or strand 2 extends. Additionally, the "circumferential direction" refers to the direction around an imaginary line (not shown) that extends along the lengthwise direction at the center of the rope 1 or strand 2. The radial direction and the lengthwise direction are perpendicular to each other.

As shown in FIG. 1, the rope 1 is constructed by twisting together a plurality of strands 2 (six in this embodiment). The rope 1 in this embodiment is a six-strand rope. Therefore, the rope 1 has a plurality of strands 2 (six in this embodiment). Furthermore, in the rope 1 of this embodiment, a core material Z is provided in the center of the plurality of strands 2 arranged in the circumferential direction. For example, a polyester rope with a diameter of 9 mm is used as the core material Z. The rope 1 of this embodiment is made of resin.

The rope 1 of this embodiment is configured so that the radial cross-sectional shape is approximately the same throughout its length. As described above, the rope 1 is configured by twisting together multiple strands 2. Therefore, in the length direction, each strand 2 is twisted circumferentially, so that the rope 1 has the same cross-sectional shape throughout its length. Therefore, the rope 1 of this embodiment has a so-called "Kintaro-ame structure." Here, the strands 2 used to configure the rope 1 of this embodiment are all of the same type. Therefore, the following description focuses on one strand 2, and is also applicable to the other strands 2.

The strand 2 is composed of multiple strands (specifically, 20 strands as shown in Figure 2) of the first yarn A, the second yarn B, and the third yarn C twisted together.

The "first yarn" is a monofilament yarn made of one single yarn, specifically a monofilament yarn with a diameter of 0.2 mm to 5.0 mm. Examples of the first yarn A include PET monofilament and PP monofilament. The first yarn A has the property of bending and deteriorating when bent. Note that "bending" here means that the bent state does not return to its original state. On the other hand, the "second yarn" is a single multifilament yarn (e.g., polyethylene multifilament yarn) made by combining several dozen single fibers, specifically an ultra-high molecular weight polyethylene fiber (HMPE) yarn with a strength of 20 cN/dT or more and a breaking elongation of 10% or less. Examples of the second yarn B include Izanas (registered trademark) SK777. The second yarn B has the property of not deteriorating even when bent, and is used, for example, in dense woven parts of clothing and firefighting suits. Therefore, the second yarn B does not bend. In addition, the second yarn B has high elasticity and is difficult to stretch. The first yarn A is more rigid than the second yarn B. Here, "rigidity" refers to an index indicating the hardness of the outer circumference and the difficulty of bending, and refers to the ability to withstand damage caused by bending or twisting. In this embodiment, all the first yarns A are PET monofilaments with a diameter of 1.5 mm, and all the second yarns B are Izanas (registered trademark) SK777 (1600d x 4 x 3) with a strength of 33 cN/dT or more.

As shown in FIG. 2, the strand 2 of this embodiment is configured in a multi-ply braided structure in which ten strands of the first yarn A and the second yarn B are twisted together to form the inner layer 4, and ten strands of the third yarn C are arranged on the surface of the inner layer 4 to form the outer layer 3. The strand 2 has a radial cross-sectional shape that is substantially the same throughout its length.

The inner layer 4 is formed by twisting together a plurality of first yarns A and second yarns B. The inner layer 4 of this embodiment includes a central portion 40 and a peripheral portion 41 that circumferentially covers the central portion 40. Therefore, the inner layer 4 of this embodiment has a multi-layer structure. The inner layer 4 is formed by twisting together the first yarns A and the second yarns B. In this embodiment, a total of 10 yarns are twisted together. Note that in the inner layer 4 of this embodiment, the number of second yarns B is greater than the number of first yarns A.

The central portion 40 is the radial center of the strand 2. In this embodiment, the central portion 40 is composed of the second yarn B. In addition, in this embodiment, the central portion 40 is composed of multiple (specifically, two) second yarns B. As shown in FIG. 2, the second yarns B constituting the central portion 40 are pressed by the peripheral portion 41 described below and are deformed in the radial direction.

The peripheral portion 41 is an intermediate layer disposed between the central portion 40 and the outer layer portion 3 described later in the cross section of the strand 2. The peripheral portion 41 is an annular layer that is aligned along the central portion 40 to cover the central portion 40. In the peripheral portion 41, the number of first yarns A and second yarns B is the same. The peripheral portion 41 of this embodiment is composed of a total of eight yarns, four first yarns A and four second yarns B. In addition, the first yarns A and the second yarns B are alternately arranged in the peripheral portion 41. Specifically, as shown in FIG. 2, the first yarns A and the second yarns B are alternately arranged in the circumferential direction so that the second yarns B are arranged to the left and right and above and below the central portion 40 (specifically, the second yarns B, B adjacent to each other on the left and right). Furthermore, in the peripheral portion 41 of this embodiment, the first yarns A and the second yarns B are alternately arranged one by one in the circumferential direction. Therefore, the peripheral portion 41 has a single-layer structure in the radial direction.

As described above, in the peripheral portion 41 that covers the central portion 40, the first yarn A and the second yarn B are arranged alternately in the circumferential direction. Therefore, in the peripheral portion 41, the first yarn A and the second yarn B are arranged in rotational symmetry in the circumferential direction with the central portion 40 as the center. Specifically, the peripheral portion 41 is configured with four-fold rotational symmetry.

As described above, in the inner layer portion 4, the first yarn A and the second yarn B constituting the peripheral portion 41 are alternately arranged so as to cover the second yarn B constituting the central portion 40. Therefore, in the inner layer portion 4, the second yarn B is arranged between the two first yarns A. In this way, what is composed of the two first yarns A and the second yarn B arranged between the first yarns A is defined as the "integral portion 4a" below. In other words, the inner layer portion 4 has an integral portion 4a. The inner layer portion 4 of this embodiment has multiple (specifically, six) integral portions 4a.

2 and 3, the integral portion 4a includes a circumferential integral portion 4b configured by arranging a second yarn B between two first yarns A in the circumferential direction, and a radial integral portion 4c configured by arranging a second yarn B (specifically, two second yarns B) between two first yarns A in the radial direction. In the inner layer portion 4 of this embodiment, four circumferential integral portions 4b and two radial integral portions 4c are configured by the arrangement of the first yarns A and the second yarns B. Note that, for ease of explanation, in FIGS. 2 and 3, one circumferential integral portion 4b and one radial integral portion 4c are shown.

The outer layer 3 covers the inner layer 4 in the circumferential direction. The outer layer 3 is disposed at the outermost side in the radial direction of the strand 2. The outer layer 3 is configured as an annular layer. The outer layer 3 prevents, for example, the first yarn A and the second yarn B configured as the inner layer 4 from coming apart. The outer layer 3 is configured by twisting together a plurality of third yarns C (10 in this embodiment). The material of the third yarn C is a film yarn or a monofilament yarn, and specifically, it is preferable that the third yarn C is a film yarn or a monofilament yarn having a fineness of 1100 dT or more. Ultra-high molecular weight polyethylene fiber (HMPE) (3000 d x 3) is used for the third yarn C in this embodiment.

As described above, according to the rope 1 of this embodiment, the second yarn B, which has been pushed and deformed by the first yarn A, fills the gaps between the first yarns A, thereby integrating the first yarns A together via the second yarn B. Therefore, the first yarns A arranged between the second yarns B, which are less likely to stretch than the first yarns A, are prevented from moving individually. For example, when tension is applied to the rope 1, it is possible to prevent permanent strain from occurring due to the stretching of the individual first yarns A, and as a result, it is possible to prevent the rope 1 from becoming loose. Specifically, in the strand 2 of this embodiment, the integrated portion 4a is formed by two first yarns A and a second yarn B arranged between the first yarns A, and the compressed second yarn B fills the gaps so that the first yarns A do not shift, and the first yarns A are integrated together. Furthermore, since the second yarn B is less stretchable than the first yarn A, it is possible to prevent the individual first yarns A from stretching and causing permanent deformation, and it is possible to prevent the rope 1 and the strand 2 that constitutes the rope 1 from becoming loose.

In addition, in this embodiment, the second yarn B is Izanas (registered trademark) SK777, which has a strength of 33 cN/dT or more, so the strand 2 can ensure a strength equivalent to that of, for example, a metal wire, and since the rope 1 using the strand 2 is made of resin, it can be made lighter than, for example, a metal wire.

In addition, in the rope 1 of this embodiment, the outer layer 3 covers the inner layer 4, so the outer layer 3 can protect the inner layer 4.

In addition, in the rope 1 of this embodiment, the inner layer 4 is covered by the outer layer 3, which increases the strength of the strand 2 and improves the strength of the rope 1 as a whole (e.g., abrasion resistance and damage resistance). Furthermore, in the strand 2 of this embodiment, the inner layer 4 includes a central portion 40 and a peripheral portion 41 that circumferentially covers the central portion 40, which improves the strength of the strand 2 as a whole.

In addition, in the rope 1 of this embodiment, the central portion 40 is made of the second yarn B, which is a multifilament, so that the central portion 40 is less likely to bend. In addition, in this embodiment, the inner layer 4 has a multilayer structure, and the central portion 40 is made of the second yarn B, so that the radial arrangement of the first yarn A and the second yarn B can form a radially integrated portion 4c. Therefore, the first yarns A can be integrated with each other in the radial direction of the strand 2, and the first yarns A can be prevented from moving individually.

In addition, since the peripheral portion 41 is disposed so as to cover the central portion 40 in the circumferential direction, it is easy to form the peripheral portion 41 around the central portion 40. Specifically, the peripheral portion 41 is an annular layer that is aligned along the central portion 40 so as to cover the central portion 40, so it is easy to form.

In addition, in the rope 1 of this embodiment, the first yarn A and the second yarn B are arranged in a rotationally symmetrical manner in the circumferential direction around the central portion 40, so that the strength of the strand 2 in the circumferential direction can be made constant. In addition, the peripheral portion 41 of this embodiment is configured with four-fold rotational symmetry, so that the aesthetic appearance of the inner layer portion 4 in the circumferential direction can be kept constant.

In addition, in the rope 1 and strand 2 of this embodiment, the first yarns A and the second yarns B are arranged alternately, so that two first yarns A with a second yarn B between them can be integrated. Since the first yarns A and the second yarns B are always adjacent to each other around the entire circumference, the first yarns A can be reliably integrated.

In addition, in the strand 2 of this embodiment, the first yarn A and the second yarn B are arranged along the second yarn B that constitutes the central portion 40, making it easy to arrange the first yarn A and the second yarn B that constitute the peripheral portion 41. In addition, the first yarn A and the second yarn B are arranged alternately around the central portion 40, so that the aesthetic appearance of the strand 2 can be kept consistent.

In addition, in the rope 1 and strand 2 of this embodiment, the central portion 40 is made up of multiple multifilament yarns, making the central portion 40 even less likely to bend, and as a result, it is possible to construct a rope 1 and strand 2 that are less likely to bend.

As shown in Figs. 2 and 3, in this embodiment, the first yarn A constitutes the radially integrated portion 4c and the circumferentially integrated portion 4b, so that the first yarns A are integrated in both the radial and circumferential directions, and the movement of each of the first yarns A can be more reliably suppressed. Specifically, when the rope 1 or the strand 2 is pulled in the length direction, the second yarn B is first compressed in the circumferential direction to fill the gaps between the first yarns A, and the first yarns A are integrated to form the circumferentially integrated portion 4b. Then, as the circumferentially integrated portion 4b is formed, the second yarn B is compressed in the radial direction as well, filling the gaps between the first yarns A, and the first yarns A are integrated to form the radially integrated portion 4c. Therefore, the integration of the first yarns A in the circumferential direction also occurs, and the movement of each of the first yarns A can be restricted in both the radial and circumferential directions.

In addition, in the inner layer portion 4 of this embodiment, the first yarn A and the second yarn B are arranged alternately so that the second yarn B is arranged to the left and right and above and below the central portion 40 in FIG. 2 along the central portion 40 formed by the second yarn B. Therefore, when the first yarns A are integrated, all the second yarns B function to fill the gaps between the first yarns A without waste, and the integrated portion 4a can be formed.

In addition, in this embodiment, the strand 2 is formed by twisting together multiple first yarns A and multiple second yarns B, so when the strand 2 is pulled in the longitudinal direction, the second yarn B is more likely to bite into the first yarn A, making it easier to form the integral portion 4a. Furthermore, in the strand 2 of this embodiment, the outer layer portion 3 is formed by twisting together multiple third yarns C, so the third yarns C run along the first yarns A and second yarns B that make up the inner layer portion 4, while the outer layer portion 3 can protect the inner layer portion 4 from the outside.

In addition, as shown in Figures 2 and 3, in this embodiment, the first yarn A and the second yarn B are arranged alternately in the circumferential direction so that the second yarn B constituting the central portion 40 is arranged to the left and right and above and below the second yarn B constituting the central portion 40 as the inner layer portion 4. As a result, the circumferential integral portion 4b and the radial integral portion 4c are arranged to intersect, and the direction of the force applied to the second yarn B also intersects. As a result, all of the first yarns A constituting the inner layer portion 4 are integrated, and permanent deformation of each first yarn A can be more reliably prevented.

In addition, in this embodiment, the first yarns A are integrated with each other via the second yarn B, which suppresses the occurrence of permanent strain and consequently maintains the rigidity of the rope 1. Therefore, in a rope 1 that maintains its rigidity, for example, when the rope 1 is wound by a winch, it is possible to prevent the second turn of the rope 1 from slipping in between the first turn of the rope 1. In addition, damage to the rope 1 due to wear can be reduced.

The rope of the present invention is not limited to the above embodiment, and the configuration may be modified, added, deleted, converted, etc. as appropriate without departing from the scope of the present invention.

In the above embodiment, all the first yarns A are described as PET monofilaments having a diameter of 1.5 mm, but this is not limiting. For example, the first yarns A may include, in addition to the PET monofilaments having a diameter of 1.5 mm, a different monofilament yarn having a diameter of 0.2 mm to 5.0 mm. The same is true for the second yarns B, which may include, in addition to Izanas (registered trademark) SK777 having a diameter of 33 cN/dT or more, a different ultra-high molecular weight polyethylene fiber (HMPE) yarn having a strength of 20 cN/dT or more and a breaking elongation of 10% or less.

In the above embodiment, the central portion 40 of the inner layer portion 4 is formed of the second yarn B, and the peripheral portion 41 is formed by alternately arranging a total of eight first yarns A and second yarns B. However, for example, the central portion 40 may be formed of the second yarn B, and the peripheral portion 41 may be formed of only eight first yarns A. That is, it is sufficient that the two first yarns A arranged in the radial direction are integrated with the second yarn B constituting the central portion 40 in between, so that the radially integrated portion 4c is arranged evenly in the radial direction. This makes it possible to suppress the individual movement of the first yarns A evenly in the radial direction in the strand 2 (specifically, in the inner layer portion 4).

In the above embodiment, the central portion 40 of the inner layer portion 4 is configured from the second yarn B. However, for example, the central portion 40 may be configured from the first yarn A, and the peripheral portion 41 may be configured by alternately arranging a total of eight first yarns A and second yarns B. That is, the two first yarns A arranged in the circumferential direction are integrated with the second yarn B in between, so that the circumferential integrated portion 4b is arranged evenly in the circumferential direction. This makes it possible to suppress the individual movement of the first yarns A evenly in the circumferential direction in the strand 2 (specifically, the inner layer portion 4).

In the above embodiment, the strand 2 is constructed by twisting the first yarn A and the second yarn B together. However, the strand 2 may be constructed by combining the first yarn A and the second yarn B, for example, by bonding them together.

In the above embodiment, the inner layer 4 is described as having a greater number of second yarns B than first yarns A. However, for example, the number of first yarns A may be greater than the number of second yarns B. In this case, it is possible that the first yarns A are adjacent to each other in the circumferential or radial direction, but the first yarns A and the second yarns B are arranged so that the rigidity of the entire strand 2 is not lost.

In the embodiment, the inner layer 4 has a multi-layer structure including a central portion 40 and a peripheral portion 41, but this is not limited thereto, and the inner layer 4 may have a single-layer structure, for example. In this case, for example, the inner layer 4 may have only the peripheral portion 41.

In the above embodiment, the central portion 40 is described as being composed of multiple second yarns B, but for example, the central portion 40 may be composed of one second yarn B, or may be composed of three or more second yarns B.

As shown in FIG. 2, in the peripheral portion 41 of the above embodiment, the first yarn A and the second yarn B are alternately arranged in the circumferential direction so that the second yarn B is arranged on the left and right and above and below the central portion 40 composed of the second yarns B, B adjacent to each other on the left and right. However, this is not limited to the above, and for example, the first yarn A and the second yarn B may be alternately arranged in the circumferential direction so that the first yarn A is arranged on the left and right and above and below the central portion 40 composed of the second yarns B, B adjacent to each other on the left and right.

In the embodiment, the case where the peripheral portion 41 has four-fold rotational symmetry has been described, but for example, the peripheral portion 41 may have three-fold or two-fold rotational symmetry, or may have five-fold or more rotational symmetry.

In the above embodiment, the second yarn B is arranged between the first yarns A in the circumferential and radial directions to form the circumferential integral portion 4b and the radial integral portion 4c, but this is not limited thereto, and the second yarn B may be arranged between the first yarns A to form only the circumferential integral portion 4b.

In the above embodiment, the strand 2 has been described as having an inner layer 4 and an outer layer 3, but for example, the strand 2 does not have to have an outer layer 3.

In the above embodiment, the outer layer 3 is described as being formed by twisting together a plurality of third yarns C. However, for example, the outer layer 3 may be a tape or cylindrical tube wrapped around the outer periphery of the inner layer 4, a material that covers the inner layer 4 with fibers such as PET or nylon, or a material that is formed by applying a liquid resin.

In the above embodiment, as shown in FIG. 2, the outer layer 3 is configured as a single layer, but the outer layer 3 may be configured as two or more layers, for example, by overlapping the third yarn C.

In the above embodiment, the central portion 40 is described as being composed of the second yarn B, but for example, the central portion 40 may be composed to include a first yarn A (or a plurality of first yarns A). When the central portion 40 is composed of a plurality of first yarns A, it is considered that the first yarn A and the second yarn B are arranged in the peripheral portion 41 so that the rigidity of the entire strand 2 is not lost.

In the above embodiment, one each of the first yarn A and the second yarn B is arranged in the peripheral portion 41, so that the peripheral portion 41 has a single-layer structure. However, for example, the peripheral portion 41 may have a multi-layer structure. In this case, two or more first yarns A or second yarns B are arranged in the radial direction. That is, the strand 2 in the above embodiment has a three-layer structure consisting of the central portion 40, the peripheral portion 41, and the outer layer portion 3, but the strand 2 may have a multi-layer structure consisting of four or more layers.

In the embodiment, the inner layer 4 is formed by twisting together a total of 10 strands of the first yarn A and the second yarn B, but this is not limited thereto. For example, the inner layer 4 may be formed by twisting together a total of 11 or more strands of the first yarn A and the second yarn B.

In the above embodiment, the rope 1 is described as having six strands, but the rope is not limited to this and may be, for example, a three strand or eight strand rope.

1: rope, 2: strand, 3: outer layer, 4: inner layer, 4a: integral part, 4b: circumferential integral part, 4c: radial integral part, 40: center part, 41: peripheral part, A: first yarn, B: second yarn, C: third yarn, Z: core material

Claims (6)

A rope formed by twisting or combining a plurality of strands each having a radial cross-sectional shape that is substantially the same throughout the length direction,
The strand is constructed by twisting or combining a first yarn made of a monofilament yarn and a second yarn made of a multifilament yarn together,
the first yarn being stiffer than the second yarn;
The second yarn has a lower elongation than the first yarn,
A rope, characterized in that the second yarn is disposed between the first yarns. The rope according to claim 1, wherein the strand comprises an inner layer portion formed by twisting the first yarn and the second yarn together multiple times, and an outer layer portion that covers the inner layer portion in the circumferential direction. The rope according to claim 1 or 2, wherein the strand comprises a central portion made of the second yarn and a peripheral portion that covers the central portion in the circumferential direction and is made of the first yarn and the second yarn. The rope described in claim 3, characterized in that in the peripheral portion, the first yarn and the second yarn are arranged rotationally symmetrically in the circumferential direction around the central portion. The rope according to claim 4, wherein the first yarns and the second yarns are arranged alternately in the circumferential direction in the peripheral portion. The rope according to any one of claims 3 to 5, wherein the central portion is composed of a plurality of the second yarns.