JP5759846B2 - Stranded ring and method for manufacturing the same - Google Patents

Description

  The present invention relates to a stranded wire ring formed endlessly with a wire rope and a method for manufacturing the same.

  Various methods for manufacturing a stranded wire ring formed of a wire rope (steel cord) have been proposed.

JP2008-291410 JP2010-248677

  In Patent Document 1, an annular metal cord is formed by winding a strand material formed by twisting six metal strands around a predetermined annular diameter, temporarily fixing a start end portion, and forming an annular core portion. An outer layer part covering the outer peripheral surface of the annular core part is formed by spirally winding the continuous strand material around the annular core part, and then using a connecting member for the start and end parts of the strand material. Are combined.

  In this manufacturing method, the outer layer portion is formed after the annular core is formed. However, in order to suppress the ring deformation when the outer layer portion is wound, a strong winding tension cannot be applied. There is a problem that it is easy to loosen and cannot be formed in a uniform state.

  Even if the ring can be formed by applying an appropriate tension, either the proposed connection member, welding, or joining by twisting the ends together can be used when joining the start and end parts. , The connecting work must be carried out with the connection part separated from the ring body to some extent. Further, since this method cannot adjust the length after connection, there is a problem that twist loosening occurs after connection.

  In Patent Document 2, an annular metal cord is divided into two wire groups having different total cross-sectional areas by untwisting a raw metal cord obtained by twisting a plurality of strand materials, and the strand material having a larger total cross-sectional area A group of reusable wire rods, a group of strands having a smaller total cross-sectional area as a non-used wire rod group, and one strand member of the reusable wire rod group is formed in a plurality of loops in the annular portion. The extra length portion is fitted into the spiral void portion from which the other strand material and the unused wire material group of the reusable wire material are removed, and is wound.

  In this manufacturing method, the contact resistance between the wires is large in the shape in which the ring has been formed, and the wires are strongly constrained. However, since the spiral void remains in the middle of the ring formation, the shape becomes unstable. Therefore, in order to suppress the ring deformation during winding, a very strong tension cannot be applied, so that there is a problem that the winding is easily loosened during the formation of the ring and cannot be formed in a uniform state.

  In addition, there is a space where the core does not exist other than the part where the terminal is inserted for connection. For example, when used as a transmission belt hung between the driving pulley and the driven pulley, when moving from the driving pulley to the driven pulley, When the generated tensile load is small or the compression load is applied, the contact resistance between the wires becomes small, and the wires can move relatively freely.

  If there is a space where the core does not exist, there is a high possibility that the wire that can move freely will fall into this space, and when a large tensile load is applied again when the transmission belt moves from the driven pulley to the driving pulley, the wire However, there is a problem that the belt breaks down early due to stress concentration on the part where the shape collapses completely into the core space.

  The present invention solves the above-mentioned problems of the prior art that are unavoidable in the process of winding a single strand in sequence or the process of untwisting a twisted steel cord and twisting it again, that is, the instability of the shape during ring formation. The purpose is to do.

  Another object of the present invention is to prevent occurrence of loose winding of a ring by carrying out terminal connection in the manufacture of a stranded wire ring.

  A further object of the present invention is to prevent stress concentration from occurring at the terminal connection site in the manufacture of the stranded wire ring.

  Another object of the present invention is to suppress fretting wear of the strands constituting the stranded wire ring or the filaments constituting the strands.

  In the method of manufacturing a stranded wire ring according to the present invention, an original wire having a length approximately twice as long as the circumferential length L of a finally manufactured stranded wire ring, and a plurality of strands twisted around the core wire. Prepare a rope.

  Next, the core wire is cut to form a butt end surface at each half L / 2 of the circumference from the center of the original wire rope to both ends, and half of the strands are cut and the remaining Untwist the uncut strand portion of

  The original wire rope is bent into a ring shape and at least the butted end surfaces formed at both ends of the core wire are butted together. In this state, the uncut strand portion on one end side of the original wire rope is connected to the other end side of the original wire rope. A part of the cut strand at the corresponding position is untwisted and replaced by twisting in place of the untwisted strand, and the replaced strand portion is cut by an amount corresponding to the replaced length. When there are a plurality of uncut strand portions on one end of the original wire rope, the above replacement is repeated with different lengths. Further, the same operation is repeated for the uncut strand on the other end side of the original wire rope.

  Wire rope means cords, steel cords, and other metal strands. The circumferential length L of the stranded wire ring is a length along the center thereof. The strand is the outermost strand. The length approximately twice the circumference L is nearly twice, and is less than twice, for example, 1.5 to 2 times, 1.6 to 2 times, or 1.7 to 2 times. This is to disperse the connection points, and the connection points may be dispersed over the entire circumference (especially when there are three or more strands). There may be a plurality of cores instead of one.

  Preferably, the strand part is replaced over a length equal to or more than two pitches of the original wire rope.

  According to the method for manufacturing a stranded wire ring according to the present invention, the wire rope of the portion that becomes the ring body is not untwisted (during the manufacturing process, only one strand that can be replaced at a time is replaced) A stable ring shape can always be maintained even during the process, and the winding tension during terminal connection processing can be properly applied. Dispersing the terminal connection part on the ring circumference can prevent stress concentration on a specific part in the manufactured stranded wire ring. Terminal connection processing can always be performed under appropriate tension, and there is no need to go through the process of lifting the connection part from the ring body during final terminal processing. Absent.

  In a preferred embodiment, the end of the strand part to be twisted and the end of the strand part to be replaced are left overlapping, and the length of the core wires overlaps at the position of the end left to overlap (there are a plurality of cores) In some cases, for example, one core wire) is cut out, the overlapping end portions are crossed, and the core wire is cut into a space formed. Although the core wire itself is cut at a plurality of locations, no gap is generated at the position of the core wire, and the shape of the stranded wire ring is not broken.

  The present invention also provides a stranded wire manufactured by the above manufacturing method.

  When the stranded wire ring according to the present invention is defined from a viewpoint different from the above, it is composed of a core wire and a plurality of strands twisted around the core wire, and is formed in an annular shape, and the core wire has both ends. , They are abutted, each strand also has both ends, and the ends of the half of the strands on both sides extend from the center where the cords are abutted to the other side, and the corresponding side The strand portion is replaced with the strand end portion and twisted, and the length of the strand portion replaced and twisted is different for each strand on both sides of the center.

  In this way, a stranded wire ring in which the connection points are dispersed throughout the ring is realized.

  In one embodiment, each of the core wire and the strand is formed by twisting a plurality of (preferably seven) first strands formed by twisting a plurality of filaments (preferably steel filaments). Second strand. The first strand is preferably formed by twisting a plurality of resin-coated steel filaments or by twisting a plurality of steel filaments and then coating them with a resin. Thereby, fretting wear due to mutual friction caused by direct contact between filaments or first strands can be suppressed, and early breakage when used as a transmission belt or the like can be prevented.

It is a perspective view which shows the completed strand wire ring. (A) shows the original wire rope with a thick line, (B) is a side view of the original wire rope, and (C) is a cross-sectional view of the original wire rope along the line II-II in (B). (A) is a diagram showing a state in which some strands are cut at both ends of the original wire rope and other strands are left, (B) is a side view thereof, and (C) is a cc in (B). (D) is an enlarged sectional view along the line dd in (B). (A) is a diagram of the original wire rope bent into a ring, and (B) is a side view of a part of it. The position of the end of each strand is shown. (A) shows the original wire rope in a straight line, and (B) shows the ring formed from the original wire rope. The configuration of the testing machine is shown.

  FIG. 1 shows the finally produced strand ring. Let L be the circumferential length (length passing through the center) of the finally produced stranded wire ring 10. Such a stranded wire ring 10 is manufactured (manufactured) as follows.

  As shown in FIG. 2, an original wire rope 10A having a length of about 2L is prepared. In FIG. 2, (A) shows the original wire rope 10A with a single thick line, (B) shows a side view of the original wire rope 10A (partially shown with a broken line), and (C) shows ( It is an expanded sectional view which follows the II-II line in the side view of B).

  This original wire rope 10A is obtained by twisting six strands 2, 3, 4, 5, 6, and 7 around a core wire (strand) 1. Each of the core wire 1 and each of the strands 2 to 7 (the core wire 1 and each of the strands 2 to 7 are referred to as second strands) is obtained by twisting seven strands (referred to as first strands) obtained by twisting a plurality of steel filaments. It is formed. That is, the original wire rope 10A has a 7 × 7 × N structure. Here, the first strand is preferably formed by twisting a plurality of resin-coated steel filaments, or by twisting a plurality of steel filaments and then coating them with a resin. Thereby, fretting wear due to mutual friction caused by direct contact between filaments or first strands can be suppressed, and early breakage when used as a transmission belt or the like can be prevented. As the resin, rubber, polypropylene resin, polyester resin, polyethylene terephthalate resin, fluorine resin, silicon resin, or the like can be used. 2 (B), (C), FIG. 3 (B), (C), (D) and FIG. 4 (B), only the thickest strand (second strand) is shown. The illustration is omitted.

  The length of about 2L of the original wire rope 10A is preferably 2L or less and close to 2L. That is, it is a length that allows replacement of strands, which will be described later, over a sufficient length and does not overlap with each other.

  As shown in FIG. 2, the central point (center) in the length direction of the original wire rope 10A is CP. The length is L / 2 in both directions from the center CP. An original wire rope portion having a length of about L / 2 (shorter than L / 2) remains at both ends.

  Next, as shown in FIG. 3, the core wire 1 of the original wire rope 10A is cut from the center CP in both end directions at positions of length L / 2 to form butt end surfaces. Further, at the position of the length L / 2 from the center CP of the original wire rope 10A to the both ends, three strands are cut at each of the left and right strands. In FIG. 3, the ends of the cut strands are the strand ends 13, 15, 17 on the left side of the original wire rope 10A, and the strand ends 22, 24, 26 on the right side. The ends of the strands having ends that remain uncut are the strand ends 12, 14, and 16 on the left side, and the strand ends 23, 25, and 27 on the right side. These remaining strand ends are cut into different lengths. For example, the strand ends 12 and 25 are left as they are, the strand ends 14 and 23 are 2/3 of the length of the strand ends 12 and 25, and the strand ends 16 and 27 are 1/3 of the strand ends 12 and 25. Of length. Adjustment of the remaining strand ends to different lengths may be made later.

  As will be described later, when the original wire rope 10A is bent into a ring shape and both end faces of the core wire 1 are butted together, the strand ends 13, 15, 17 having the left-side cut end faces and the remaining strand ends on the right side The strand ends 22, 24, 26 with the cut ends on the right side and the remaining strand ends on the left side, with the sections 23, 25, 27 in corresponding positions (these strand ends are swapped as described below) The strands to be cut and the remaining strands are selected so that the portions 12, 14, and 16 are in corresponding positions (the ends of these strands are replaced as will be described later).

  The original wire rope 10A is composed of the core wire 1 and the strands 2 to 7 twisted around the core wire 1. The ends of these strands 2 to 7 correspond to any of the strand end portions 12 to 17 and 22 to 27. I don't know or make it a problem.

  3C is a cross-sectional view taken along the line cc in FIG. 3B, and FIG. 3D is a cross-sectional view taken along the line dd in FIG. 3B. It should be noted that the cc line and the dd line are different in the direction of the arrow (direction of viewing the cross section).

  Thereafter, as shown in FIG. 4A, the central length L of the original wire rope 10A is bent into a ring shape. FIG. 4B is an enlarged view of the end portion of the original wire rope 10A in FIG.

  Further, the original wire rope 10A is bent into a ring shape, and at least the butted end surfaces formed by cutting the core wire 1 are butted together.

  5 (A) and 5 (B), for example, the strand end portion 12 left uncut on the left end side of the original wire rope 10A is replaced with the strand end portion on the right end side of the corresponding original wire rope 10A. While untwisting 22, the strand end 12 is replaced and twisted in place of the untwisted strand end 22. Then, the replaced strand end portion 22 is cut by a length corresponding to the length replaced with the strand end portion 12. At this time, terminal processing is preferably performed as follows. That is, the strand end portion 12 to be twisted and the strand end portion 22 to be replaced are left overlapping, and the length of the core wire 1 that overlaps at the position of the end portion left overlapping is excised and left redundant. The end portions 12 and 22 are crossed, and the core wire 1 is cut into a space formed. The length of the portion where the strand end 22 is replaced by the strand end 12 is preferably about 2 to 3 times the strand twist pitch (2 to 3 pitch).

  Next, the remaining strand end 14 on the left end side of the original wire rope 10A (the length thereof is about 2/3 of the strand end portion 12) is also replaced in the same manner as the right end strand end portion 24. The last strand 16 on the left end side (its length is about 1/3 of the strand end portion 12) is also replaced with the strand end portion 26 on the right end side.

  Further, the strand ends 23, 25, 27 on the right end side are similarly replaced by twisting the corresponding strand ends 13, 15, 17 on the left end side while untwisting.

  The end portions of these strand ends are accommodated in a space formed by cutting the core wire 1 by a length corresponding to the overlapping length. Although the core wire 1 is cut out at a number of locations, the space of the core portion of the manufactured strand wire ring is filled with the core wire 1 portion or the end portion of the strand, leaving a void inside. There is no.

  In FIGS. 5A and 5B, the positions where the ends of the strands 12, 14, 16, 23, 25, and 27 to be twisted for replacement are respectively indicated as 12e, 14e, 16e, 23e, 25e, and 27e. It is shown in

  Thus, the stranded wire ring 10 shown in FIG. 1 is completed.

  Table 1 shows an example. Examples 1 to 12 (NO. 1 to 8, NO. 13 to 16) are all formed in an annular shape by the above-described method (distributed arrangement of 6 connection positions). Regarding “resin coating”, “strand” indicates that the first strand is formed by twisting a plurality of steel filaments, and then this first strand is resin-coated. A plurality of steel filaments are twisted together to form a first strand. The resin used was a polyester resin, and the coating thickness was 30 μm for the filament and 50 μm for the strand. Comparative Examples 1 to 3 (NO. 9 to 11) are formed by the method disclosed in Patent Document 1, and Comparative Example 4 (NO. 12) is formed by the method disclosed in Patent Document 2. In addition, N = 3 + 9 + 15 in NO.1, 2; N = 1 + 6 + 12 in NO.3, 4; N = 3 + 9 in NO.5, 6 and these correspond to the first strand to be coated. The timing for coating these first strands is at the exit of the stranding machine where the first strand (3 + 9 + 15, 1 + 6 + 12 or 3 + 9) is created. The first strands of these structures are expected to have a greater effect of fretting wear occurring between the first strands than the fretting within the first strands. That is why.

  The wire ropes used in these examples and comparative examples were manufactured as follows.

  The 5.5 mm diameter wire containing the component corresponding to JIS G3502 SWRH72A is removed with hydrochloric acid, then treated with borax film and dried. After wire drawing with a dry continuous wire drawing machine, it is austenitized in a heating furnace at 1000 ° C and then heat-treated by patenting in a fluidized bed furnace at about 550 ° C. Thereafter, descaling, wire drawing, and heat treatment are repeated an appropriate number of times to obtain a desired wire diameter. During the final heat treatment, after removing the scale in-line, copper and zinc were electroplated in this order so that the copper ratio was about 65 wt%, and the copper and zinc were mutually connected in a fluidized bed furnace at about 560 ° C. Diffuse into brass-plated wire. The resulting brass-plated wire is subjected to final wire drawing using a wet continuous wire drawing machine to obtain a strand used for stranded wire.

  A plurality of strands obtained as described above are used, and the first strand is twisted together with a tubular type or double twist type twisting machine. At that time, a resin coating is applied to the strands before twisting or the first strand after twisting. Next, the second strand is twisted together with a tubular type twisting machine. Finally, 7 × 7 × N wire rope (steel cord) is twisted together with a tubular type twisting machine.

  The durability test method is as follows.

  The stranded wire is used, for example, as a transmission belt (its reinforcing material) such as a timing belt of an ink jet printer or a belt conveyor of a small transport device. The timing belt or the driving belt is set by applying a predetermined tension between the driving pulley and the driven pulley. When the belt is driven, the tension applied to the belt moving from the driven pulley toward the driven pulley increases, and conversely, the tension applied to the belt moving from the drive pulley toward the driven pulley decreases.

  In order to carry out an endurance test to reproduce the load mode of the belt drive as described above, in the endurance test, as shown in FIG. 6, two metal pulleys with a diameter of 40 mm provided so as to be opposed to each other are separated. Use the tester you have. One side is a motor driven side and the other side is a driven side, and a stranded wire ring (evaluation sample) is hung between these two pulleys. Rotate the drive pulley while applying a tensile load to the driven pulley, and conduct the test until the evaluation sample breaks. In order to suppress vibration of the evaluation sample between the two pulleys, a plurality of guide pulleys are provided at appropriate intervals.

  In this evaluation, the tensile load was set to 10% of the cord cutting load, and the drive pulley was driven at a maximum rotation speed of 3000 rpm so that forward rotation and reverse rotation were repeated alternately at 10-minute intervals. In the durability test, the number of rotations of the testing machine (regardless of forward or reverse) was recorded and displayed as an index with the result of Comparative Example 1 being 100.

  As can be seen from the durability test results (index) in Table 1, it can be seen that any of Examples 1 to 12 has higher durability than the conventional example. Moreover, in Examples 1-12, since the connection part is disperse | distributed to six places (6 last terminal fixing points shown to FIG. 5 (A), (B)), like Comparative Examples 1-3 There is no breakage at the connection. It can also be seen that the durability is dramatically improved in the case where the strands or filaments are resin-coated (Examples 2, 4, 6, 8, 10, 12).

  According to this embodiment, the following effects are obtained.

  By forming the wire rope (steel cord) of the ring main body without untwisting, it is possible to always maintain a stable shape even during the process and to properly apply the winding tension during terminal connection processing. it can.

  Dispersing the terminal connection part on the ring circumference can prevent stress concentration on the specific part.

  Terminal connection processing is always performed under proper tension, and there is no step of lifting the connection part from the ring body even during processing of the final terminal, so that no loosening of winding occurs after the final processing.

  By applying a double double twist structure of 7 × 7 × N, it is possible to provide sufficient flexibility to follow a complicated stress change when used as a transmission belt.

  By using the resin-coated filament or the resin-coated first strand, fretting wear between the filaments and between the first strands can be suppressed, and early breakage when used as a transmission belt or the like can be prevented.

1 Core wire (Strand)
2,3,4,5,6,7 strand
10 Stranded ring
10A original wire rope (steel cord)
13, 15, 17, 22, 24, 26 Cut strand ends
12, 14, 16, 23, 25, 27 Strand ends left uncut
12e, 14e, 16e, 23e, 25e, 27e Final terminal fixed point

Claims (12)

Prepare an original wire rope having a length approximately twice the circumference L of the strand wire ring to be finally produced, and a plurality of strands twisted around the core wire,
The core wire is cut at each half L / 2 of the circumference from the center of the original wire rope to form a butt end face, and half of the strands are cut and the remaining uncut Untwist the strand part,
Bending the original wire rope into a ring shape, butting the butted end surfaces formed at least at both ends of the core wire,
In this state, the uncut strand portion on one end side of the original wire rope is twisted in place of the untwisted strand while untwisting a part of the cut strand at the corresponding position on the other end side of the original wire rope. About the replaced strand part, the part corresponding to the replaced length is excised,
When there are a plurality of uncut strand portions on one end of the original wire rope, the lengths of the portions are distributed over the entire half-circumference of the other end on the ring circumference. And repeat the above replacement,
Furthermore, the same operation as above is repeated for the uncut strand on the other end of the original wire rope.
A method for manufacturing a stranded wire ring in which terminal connection points are dispersed over the entire circumference of the ring .   The manufacturing method according to claim 1, wherein the replacement of the strand portion is performed over a length equal to or more than two pitches of the twist pitch of the original wire rope.   The end of the strand part to be twisted and the end of the strand part to be replaced are left overlapped, and the length of the core wire is cut off at the position of the end part left overlapped and left redundant. The manufacturing method according to claim 1 or 2, wherein the end portions are crossed to be inserted into a space formed by cutting the core wire.   4. The production according to claim 1, wherein each of the core wire and the strand is a second strand formed by twisting a plurality of first strands formed by twisting a plurality of filaments. 5. Method.   The manufacturing method according to claim 4, wherein the first strand is formed by twisting a plurality of resin-coated steel filaments.   The manufacturing method according to claim 4, wherein the first strand is formed by twisting a plurality of steel filaments and then coating with a resin.   A stranded wire manufactured by the manufacturing method according to any one of claims 1 to 6. It consists of a core wire and a plurality of strands twisted around it.
The core has both ends and they are abutted,
Each strand also has both ends,
The ends of the half of the strands on both sides of the centered portion of the core wire extend to the other side, and are twisted by replacing the corresponding strand ends on the other side.
The lengths of the strand portions that are twisted by replacement are distributed so that the ends of the plurality of strand portions that extend to the other side on both sides of the center are distributed over the entire range of the other half of the ring circumference. It is different for each strand to,
A twisted wire ring with terminal connection points distributed around the entire circumference of the ring.   The strand wire ring according to claim 8, wherein the strand replacement is at least 2 twist pitches, and the difference in replacement length for each strand is also at least 2 twist pitches.   The strand wire ring according to claim 8 or 9, wherein each of the core wire and the strand is a second strand formed by twisting a plurality of first strands formed by twisting a plurality of filaments.   The stranded wire ring according to claim 10, wherein the first strand is formed by twisting a plurality of resin-coated steel filaments.   11. The stranded wire ring according to claim 10, wherein the first strand is formed by twisting a plurality of steel filaments and then coating with a resin.

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