EP0845552A2

EP0845552A2 - Carrier tape and fabric for rapier loom

Info

Publication number: EP0845552A2
Application number: EP97119289A
Authority: EP
Inventors: Masahiko Kimbara; Makoto Tsuzuki; Masahiko Yasue
Original assignee: Toyoda Jidoshokki Seisakusho KK; Toyoda Automatic Loom Works Ltd
Current assignee: Toyota Industries Corp
Priority date: 1996-11-05
Filing date: 1997-11-04
Publication date: 1998-06-03
Also published as: KR19980042060A; CN1183489A; EP0845552A3

Abstract

A carrier tape for use in a rapier loom. The carrier tape is formed of fiber reinforced plastic. A fabric band (1) is used as a reinforcing material for the plastic. The fabric band (1) is substantially the same size as the carrier tape. The fabric band (1) contains a yarn (2) arranged obliquely to a lengthwise direction of the fabric band (1), and the yarn (2) is woven to be folded, or angled, at the sides of the fabric band (1).

Description

The present invention relates to a carrier tape for a rapier loom and a fabric suitable for a reinforcing material for a fabric reinforced composite carrier tape.

One known weft insertion device for a rapier loom is equipped with a carrier tape, which has a rapier head secured to its distal end, and a rapier wheel on which the carrier tape is wound. As the rapier wheel of this weft insertion device rotates reciprocally, the carrier tape reciprocates in accordance with the rotation. The rapier head enters the shed in accordance with the forward movement of the carrier tape and moves out of the shed in accordance with the backward movement of the carrier tape. Then, the weft is inserted in the shed.

A weft insertion device disclosed in Japanese Patent Publication No. Sho 60-40538 has a rapier head 52 secured to the distal end of a carrier tape 51 as shown in Figure 21. The carrier tape 51 has its proximal end secured to the outer surface of the rapier wheel 53 and is wound around the rapier wheel 53. Two

rollers

54 and 55 are provided above the rapier wheel 53 to prevent the carrier tape 51 from being lifted from the outer surface of the rapier wheel by the centrifugal force generated by the rotation of the rapier wheel 53. A rope 56 is wound around the rapier wheel 53 and both

rollers

54 and 55 to press the carrier tape 51 against the winding surface of the rapier wheel 53. The reciprocal rotation of the rapier wheel 53 permits insertion of the weft into the shed.

A device disclosed in Japanese Unexamined Patent Publication No. Hei 3-180542 uses a drive sprocket as the rapier wheel 53 as shown in Figure 22. The carrier tape 51 has engagement holes 51a, which are to engage with the teeth 53a of the drive sprocket and are formed with a predetermined pitch in the lengthwise direction of the carrier tape 51. The reciprocal rotation of the rapier wheel 53 is transmitted to the carrier tape 51 based on the engagement of the teeth 53a with the associated engagement holes 51a, causing the carrier tape 51 to reciprocate in accordance with the reciprocal rotation of the rapier wheel 53.

There are plastic carrier tapes and fiber reinforced plastic (FRP) carrier tapes. A polyester carrier tape is one example of a plastic carrier tape. As shown in Figure 23, one FRP carrier tape has two plain fabrics W1, which are provided on the top and bottom faces of the carrier tape 51, and a stack of fabric layers W2 and W3 between the plain fabrics W1. Each fabric layer W2 has fibers aligned in the longitudinal direction of the carrier tape 51. Each fabric layer W3 has fibers extending in a direction obliquely intersecting the longitudinal axis of the carrier tape 51. The engagement holes are punched out by press working.

A carrier tape disclosed in Japanese Unexamined Utility Model Publication No. Hei 2-125979 has a laminar structure including a number of foundation cloths. The carrier tape has a reinforcing material provided in at least a layer of the laminar structure extending in the longitudinal direction, outside the sprocket engagement holes, which are arranged in the longitudinal direction.

A plastic carrier tape or a fiber reinforced plastic carrier tape, which contains some reinforcing fibers, when used, deforms in accordance with the curvature of the outer surface of the rapier wheel. Further, because of its low rigidity, the carrier tape fed out from the rapier wheel tends to bend downward. When the carrier tape is retracted, the distal end of the carrier tape is thrust downward. With no guide member present, therefore, the rapier head is not linearly thrust into the shed, nor does it linearly retract therefrom.

In view of the above, therefore, guide

members

57a and 57b, which enter the shed from the lower side of the warp Y at the time the shed is opened to guide the carrier tape 51, are needed, as shown in Figure 24. The

guide members

57a and 57b are alternately arranged in the lengthwise direction of an unillustrated slay where reeds are supported. Because the

guide members

57a and 57b move in and out of the shed due to the rocking of the slay, the warp Y may be hooked on the

guide members

57a and 57b and may be cut. Another shortcoming is that the warp Y may be fuzzed by friction due to contact with the

guide members

57a and 57b.

Meanwhile, since the FRP carrier tape 51, which includes a stack of fabric layers, is very rigid, the rapier head is held stable, and is thus smoothly thrust into and out of the shed. This ensures smooth handing of the weft.

Because feeding of the carrier tape 51 out of the rapier wheel 53 and winding of the carrier tape 51 therearound are repeated for each weft insertion, bending stress is frequently applied to the carrier tape 51. When stress is applied to a fiber reinforced composite, the composite is apt to be broken at the side surfaces, if cut fiber surfaces are present there, thus, significantly reducing the strength of the carrier tape 51. Since a conventional FRP carrier tape 51 has individual fabric layers W1-W3 arranged in such a way that cut fiber surfaces are located at both side edges of the carrier tape 51, interlayer shear fracture is likely to occur from the side surfaces of the carrier tape 51 as shown in Figure 25. Also, the rung-like portion between the engagement holes 51a is subject to complex deformation, so that interlayer shear fracture is liable to occur there as well. Furthermore, as shown in Figure 22, surface peeling may occur due to the engagement between the teeth 53a of the rapier wheel 53 and the edges of the engagement holes 51a during disengagement.

Because conventional FRP carrier tape 51 has no yarn passing through the stacked fiber layers, the aforementioned interlayer shear fracture and surface peeling will continue and will worsen with continued use. Therefore, the life of the carrier tape is reduced.

It is a first objective of this invention to provide a durable rapier loom carrier tape that allows a rapier head to be thrust into and out of a shed while being held in a stable manner.

It is a second objective of this invention to provide a carrier tape that is not completely broken, even when its lifetime is over, and thus does not break off with a part of the carrier tape and the attached rapier head remaining at the weaving section of a loom during the beating-up step, while maintaining the advantages of the carrier tape of the first objective.

It is a third objective of this invention to provide a fabric suitable as a reinforcing material for a fiber reinforced composite, which forms the aforementioned carrier tape.

To achieve the first objective, the carrier tape according to this invention is formed of fiber reinforced plastic. A fabric band, which is substantially the same size as the carrier tape, is used as a reinforcing material for reinforcing the tape. The fabric band includes a yarn arranged obliquely to a longitudinal direction of the fabric. The yarn is woven to be folded at the sides of the fabric.

The "yarn" includes a bundle of fibers with filaments aligned without being twisted, as well as a twisted yarn.

To achieve the second objective, the fabric band of the carrier tape according to the present invention is an interconnected fabric. Furthermore, most of the yarn constituting the fabric is of a first yarn having a large modulus of elasticity. At least one second yarn is arranged along substantially the entire length of the fabric band and has a larger elongation at its breaking point than the first yarn.

To achieve the third objective, the fabric according to the present invention includes a fabric band having substantially the same width and thickness as the carrier tape. The fabric includes a yarn arranged obliquely to a longitudinal direction of the fabric. The yarn is woven to be folded at the sides of the fabric.

Furthermore, the yarn constituting the fabric is an interconnected integral fiber. Most of the yarn constituting the fabric band is a first yarn with a large modulus of elasticity. At least one second yarn is arranged along substantially the entire length of the fabric band and has a larger elongation at its breaking point than the first yarn.

The features of the present invention that are believed to be novel are set forth with particularity in the appended claims. The invention, together with objects and advantages thereof, may best be understood by reference to the following description of the presently preferred embodiments together with the accompanying drawings in which:

Figure 1 is a schematic perspective view showing a band of fabric according to the first embodiment;

Figure 2 is a schematic perspective view showing how the fabric is woven;

Figure 3 is a schematic perspective view of a carrier drive unit;

Figure 4 is a diagrammatic plan view for explaining the arrangement of rotors and yarn carriers;

Figures 5(a) - 5(c) are diagrammatic plan views illustrating the loci of yarn in carriers when the rotors are turned 90 degrees;

Figure 6(a) is a schematic plan view of yarn carriers and horn gears of a square braider for use in weaving a fabric according to the second embodiment;

Figure 6(b) is a schematic plan view of a frame;

Figure 6(c) is a schematic plan view showing the positional relationship between the frame, the horn gears and yarn carriers;

Figure 6(d) is a diagrammatic plan view illustrating the loci of the yarn carriers;

Figure 7 is a partially cut-away schematic perspective view of a fabric according to the third embodiment;

Figure 8 is a schematic plan view of a band of fabric according to the fourth embodiment;

Figure 9(a) is a schematic plan view of horn gears of a braider for flat braid;

Figure 9(b) is a schematic plan view of a frame;

Figure 9(c) is a schematic plan view showing the positional relationship between the frame, the horn gears and bobbin carriers;

Figure 9(d) is a diagrammatic plan view illustrating the loci of yarn in the bobbin carriers;

Figure 10 is a schematic plan view of another band of fabric;

Figure 11 is a schematic plan view of a band of fabric according to the fifth embodiment;

Figure 12 is a schematic plan view of another band of fabric;

Figure 13 is a partial schematic perspective view showing a part of a carrier tape according to the sixth embodiment;

Figure 14 is a schematic plan view for explaining the arrangement of rotors and yarn carriers;

Figure 15 is a partial schematic perspective view showing a part of a carrier tape according to the seventh embodiment;

Figure 16(a) is a schematic plan view of horn gears of a braider for round braid;

Figure 16(b) is a schematic plan view of a frame;

Figure 16(c) is a schematic plan view showing the positional relationship between the frame, the horn gears and bobbin carriers;

Figure 16(d) is a diagrammatic plan view illustrating the loci of yarn in the bobbin carriers;

Figure 17 is a schematic perspective view showing how a three-dimensional band of fabric according to a modification is woven;

Figure 18 is a partial schematic perspective view of a carrier tape according to a modification;

Figure 19 is a partial schematic perspective view of a carrier tape according to another modification;

Figure 20 is a partial schematic perspective view of a carrier tape according to a further modification;

Figure 21 is a schematic side view of a conventional weft insertion device for a rapier loom;

Figure 22 is a schematic side view illustrating the relationship between a rapier wheel and a conventional carrier tape;

Figure 23 is a partially cut-away schematic perspective view of a conventional FRP carrier tape;

Figure 24 is a schematic side view showing the relationship between guide members of a rapier loom and warp; and

Figure 25 is a partial schematic perspective view showing a detective carrier tape.

The first embodiment of the present invention will now be described with reference to Figures 1 - 5. Figure 1 is a schematic perspective view of a reinforcement fabric band 1, which is used for a fiber reinforced plastic carrier tape for a rapier loom. The fabric band 1 is comprised of a three-dimensional braid, which is formed with substantially the same width and thickness of the carrier tape. The thickness of the fabric band 1 is chosen to effect a rigidity such that, when the fabric band 1 is used for an FRP carrier tape, the carrier tape is movable in a shed while being extended at the time of weft insertion without the need for guide members. The thickness of the fabric band 1 is about 1 to 3 mm. The fabric band 1 has a substantially rectangular cross section and has multiple yarns 2 folded back, or angled inward, on the surface of the fabric 1 and arranged to extend at an angle (alignment angle) to the longitudinal axis of the fabric band 1. Therefore, the yarns 2 constituting the fabric 1 are folded, or angled, at both sides of the fabric 1, so that cut ends are not exposed at the side edge. The "alignment angle" is the angle formed between the layout direction of the yarns 2 and the longitudinal axis of the fabric base 1. The value of the alignment angle is preferably set within the range of ±1° to ±60°, and is normally set to ±3° to ±15°. An untwisted yarn comprised of fibers with a high breaking strength and a large modulus of elasticity, such as carbon fibers or ceramic fibers, is preferably used as the yarn 2.

The fabric band 1 is woven with a braider for three-dimensional braid as disclosed in, for example, Japanese Unexamined Patent Publication No. Hei 2-259148 or Japanese Unexamined Patent Publication No. Hei 2-307949. As shown in Figure 2, the braider for three-dimensional braid has carrier drive units 3 arranged in multiple rows and multiple columns along the carrier plane, which is perpendicular to the longitudinal axis of the band of fabric 1. Each carrier drive unit 3 causes a yarn carrier 4 (shown in Figure 3), which supports an unillustrated bobbin, to run along a predetermined path. The fabric is woven with the yarns 2 fed from those bobbins.

The carrier drive units 3 are equipped with rotors 6, which are driven by independent actuators 5. Each rotor 6 has recesses 7 formed at four locations in its outer surface for holding the associated yarn carrier 4 with an adjoining rotor 6. The recesses 7 are defined by arcs, the centers of which coincide with the axes of the rotary shafts of the rotors 6, so that when one of the rotors 6 rotates, the corresponding recess 7 of the adjoining rotor 6 serves as a guide for the yarn carrier 4. Note that a fixed guide 8 frames the carrier drive units 3, which are arranged in multiple rows and multiple columns, as shown in Figure 2. The fixed guide 8 has recesses 8a that engage with the yarn carriers 4.

As shown in Figure 3, each yarn carrier 4 includes a convex lens-shaped held portion 9 having a pair of arc surfaces 9a (only one shown) corresponding to the recesses 7 of the rotor 6, flanges 10 formed at both ends of the held portion 9, and a bobbin support rod 11. The held portion 9 of the yarn carrier 4 is held between the adjoining rotors 6 or between the rotor 6 and the fixed guide 8.

In the case where the fabric 1 is woven with a braider for three-dimensional braid with the above-described structure, the yarn carriers 4 are arranged in accordance with the cross-sectional shape of the fabric 1 in a moving area. At the time of weaving the fabric 1, the rotors 6 are separated into two groups. Each of the groups includes alternate rotors along the rows and columns so that adjacent rotors of a row or column are in different groups. The rotors 6 of each group are driven together. In Figure 4, the two groups of rotors are distinguished from each other by the presence or absence of cross hatching. Hereinafter, the hatched rotors 6 in Figure 4 will be called the first group of rotors, and the unhatched rotors 6 will be called the second group of rotors. The first group of rotors intermittently rotate 90 degrees or 180 degrees clockwise, and the second group of rotors intermittently rotate 90 degrees or 180 degrees counterclockwise.

In weaving the fabric, first, with one group of rotors unrotated to serve as fixed guides, the rotors in the other group are rotated 90 degrees or 180 degrees in one direction. Then, the other group of rotors are treated as fixed guides, while the rotors in the one group are rotated 90 degrees or 180 degrees in the reverse direction. The fabric 1 band is woven by repeating this operation.

The yarn carriers 4 move in their layout range in a relatively simple and regular manner during weaving of the fabric 1. When the yarn carriers 4 are held between adjoining rotors 6 and the first group of rotors 6 and the second group of rotors 6 are rotated 90 degrees in Figure 4, for example, the loci of the yarn in the individual yarn carriers 4 is as shown in Figures 5(a) - 5(C), respectively. Specifically, the yarns 2 that are fed out from the bobbins supported on the yarn carriers 4 move while forming a closed loop along curves shown in Figures 5(a) to 5(c). When the first group of rotors and the second group of rotors are rotated 180 degrees, different moving paths result. As both groups of rotors are rotated 90 degrees or 180 degrees sequentially in the opposite directions, therefore, the fabric band 1, with the yarns 2 folded inward on each surface, is woven. In other words, the yarns are folded to define the different surfaces of the band and are not cut, as shown in Fig 1.

Beating-up can be done during the weaving of the fabric 1 as needed, and the alignment angle of the yarns 2 of the fabric 1 can be controlled by adjusting the degree of reeding and the take-up speed of the woven fabric.

In the case of manufacturing an FRP carrier tape with the thus woven fabric band 1 as a reinforcing material, the fabric 1 is impregnated with resin and is then hardened. The resin impregnation and curing are carried out by a resin transfer molding method, for example. The fabric 1 is placed in a mold, and a thermosetting matrix resin is injected into this mold to impregnate the fabric band 1. The resin is then thermoset to produce an FRP carrier tape. The resin used may be an epoxy resin.

When a sprocket is used as a rapier wheel for driving the carrier tape, holes that engage with the teeth of the sprocket are formed in the carrier tape. The holes are formed by press working or drilling after the FRP carrier tape is manufactured. Alternatively, the mold for resin impregnation may be provided with projections so that the holes can be formed at the time of resin impregnation.

According to this embodiment, the fabric 1 is formed in a band shape, the thickness of which effects a rigidity that allows the resulting FRP carrier tape to be movable in a stable manner at the time of weft insertion. It is therefore possible to move the carrier tape in and out of the shed in accordance with the rotation of the rapier wheel while keeping the rapier head stable, without guide members. This prevents wear of the carrier tape by friction between guide members and the carrier tape, thus increasing the life of the carrier tape.

As the fabric 1 is woven in such a way that the yarns 2 are folded, or angled, at sides of the fabric 1, there are no cut fiber surfaces present at either side of the carrier tape. Even when bending stress is frequently applied to the carrier tape, therefore, the carrier tape resists breakage along its side surfaces. The resulting carrier tape is therefore more durable as compared with the conventional FRP carrier tape, which is reinforced with laminated fibers.

Since the fabric band 1 consists of a three-dimensional braid, when it is used for a carrier tape, there are no interfaced between layers. Or, in other words, there is only one integral layer. Even when bending stress is repeatedly applied to the carrier tape, therefore, interlayer separation does not occur, unlike in the conventional type, which uses a reinforcing material having laminated flat fabrics. Therefore, a carrier tape made with the three-dimensional braid of Fig. 1 is more durable.

In the case of conventional carrier tape formed with engagement holes, which engage with the teeth of a sprocket, interlayer separation may occur due to the friction between the teeth and the holes when the teeth disengage from the holes. Since the fabric 1 of Fig. 1 has no layer interfaces, interlayer separation does not occur. Additionally, there are yarns extending thicknesswise (from top to bottom), obliquely intersecting the longitudinal axis of the carrier tape. Therefore, surface peeling of the fabric band is impeded from spreading to a point at which the separation reaches the warp, which would adversely affect the quality of the fabric in the loom and the working efficiency of the loom.

Because the fabric 1 consists of a three-dimensional braid, if a mold for the impregnation and curing of a resin is provided with projections to form sprocket engagement holes, the projections easily penetrate between the yarns 2 of the fabric band 1. Since a carrier tape with holes formed in this manner, unlike one having holes formed by press working or drilling after resin molding, does not have cut fiber surfaces around the holes, surface peeling by the friction between the teeth of the sprocket and the holes is prevented, and interlayer shearing from around each hole is prevented.

The second embodiment will now be discussed with reference to Figure 6. This embodiment differs from the first one in that a square braider is used as the three-dimensional braider for weaving a three-dimensional braid. While the structure of the fabric band 1 of this embodiment differs from that of the three-dimensional braid of the first embodiment in the strict sense, they are the same in that the yarns 2 are folded, inward, or angled on the surface of the fabric 1 and are arranged at a predetermined alignment angle with respect to the longitudinal axis of the band of fabric 1. An FRP carrier tape produced by using this fabric 1 as a reinforcing material has advantages similar to that of the first embodiment.

The structure of the square braider will be discussed below. The square braider has a frame 14 having a guide groove 13 for guiding yarn carriers 12 in movement, as shown in Figure 6(b). As shown in figure 6(a), horn gears 15, which are similar to the rotors 6, are formed like disks, each having four recesses 15a formed at equal angular intervals in its outer surface for engaging and driving the yarn carriers 12. The horn gears 15 are designed to be synchronously rotated via unillustrated gears. Each yarn carrier 12 has a cylindrical held portion 12a, which is engaged by the recesses 15a of the associated horn gear 15, and an engage portion 12b (marked black in Figures 6(a) to 6(d)), which is engageable with the guide groove 13. The yarn carriers 12 are moved along the guide groove 13 by the rotation of the horn gears 15.

With this braider for three-dimensional braid, adjacent horn gears 15, with respect to rows and columns, are rotated in the opposite directions, as in the previous embodiment. Unlike in the previous embodiment, however, the horn gears 15 are rotated continuously, not intermittently. The number of the yarn carriers 12 used in weaving a fabric is equal to the number of the horn gears 15, which is considerably less than the number of the yarn carriers 4 per rotor 6 of the first embodiment.

In weaving the fabric 1 with this braider for three-dimensional braid, the yarn carriers 12 are arranged in association with the horn gears 15 as shown in Figure 6(c), and weaving is initiated from this state. As the individual horn gears 15 are driven in predetermined directions, the moving loci of the individual yarn carriers 12 are indicated by the solid line, broken line, one-dot chain line and two-dot chain line in Figure 6(d), and the yarns 2, which are released from bobbins supported on the yarn carriers 12, move to form closed loops along the associated curves in Figure 6(d). As a result, the fabric 1 is woven with the yarns 2 arranged to be folded inward, or angled, at each surface.

The third embodiment will now he described with reference to Figure 7. The fabric 1 according to this embodiment comprises a three-dimensional fabric having a plurality of laminated fiber layers with yarns penetrating each fiber layer. As shown in Figure 7, the fabric 1 comprises an appropriate number of the following: warp layers 17, each consisting of a warp Y; weft layers 18, each consisting of a weft X; bias yarn layers 19, each consisting of a bias yarn B1; and bias yarn layers 20, each consisting of a bias yarn B2. The individual yarn layers 17 to 20 are connected by connection yarns Z, which ore arranged to penetrate all the respective yarn layers. The connection yarns Z pass from top to bottom and are folded to make 180 degree turns at the wide surfaces, or the top and bottom, of the fabric band 1. The warps Y are arranged along the longitudinal axis of the fabric 1, and the wefts X are arranged in a folded manner (180 degree turns) in the widthwise, or side to side, direction of the band of fabric 1 to be perpendicular to the warps Y. The bias yarns B1 are arranged in a folded manner in a transverse direction of the band of fabric 1 to have a predetermined angle to the longitudinal axis of the band of fabric 1, and the bias yarns B2 are arranged to intersect the longitudinal axis of the fabric 1 at an inclination angle that is opposite to that of the bias yarns B1. The connection yarns Z are locked by lock yarns P1.

This fabric 1 can be manufactured by a method disclosed in, for example, Japanese Unexamined Patent Publication No. Hei 5-272030. Specifically, after a predetermined number of the individual yarn layers are laminated, the connection yarns Z are inserted to penetrate all the individual yarn layers 17-20 and are then locked by the lock yarns P1.

This fabric 1, like the fabric band 1 of the previous embodiment, is formed into an FRP carrier tape after undergoing resin impregnation and curing. If holes are necessary, they can be formed by press working or drilling as in the first embodiment. This carrier tape, like that of the first embodiment, can be thrust into and out of the shed in accordance with the rotation of the rapier wheel. Further, the durability of the carrier tape is greater than that of the conventional FRP carrier tape, which uses laminated fibers as a reinforcing material.

Furthermore, unlike the fabric band 1 woven by a braider for three-dimensional braid, this fabric band 1 has planar yarn layers (fiber layers), which are parallel to the plane of the band of fabric band 1. Since the individual yarn layers 17-20 are sewn together by the connection yarns Z, which are arranged to penetrate the individual yarn layers 17-20, however, even when bending stress is frequently applied to the carrier tape, causing localized interlayer shear fracture or surface peeling, such interlayer shear fracture or surface peeling is significantly impeded and progresses little. Therefore, the durability of the carrier tape is improved as compared with that of the conventional carrier tape, which has fiber layers simply laminated in the thicknesswise direction and has no yarns penetrating the stacked fiber layers.

The fourth embodiment will now be described with reference to Figures 8 - 10. In this embodiment, the fabric 1 consists of a flat braid. As shown in Figure 8, the fabric 1 has multiple yarns 2 arranged to be folded back, or, angled, on the surface of the fabric 1 and to have a predetermined alignment angle to the longitudinal axis of the fabric 1. Because, unlike a three-dimensional braid, the flat braid has only two yarns 2 arranged in the thicknesswise direction (perpendicular to the plane of Fig. 2) of the fabric 1, it is not possible to increase the number of yarns arranged in the thicknesswise direction of the fabric 1 to achieve the desired rigidity. However, varying the thickness of the individual yarns 2 can vary the rigidity. Therefore, the desired rigidity can be achieved. This fabric 1 is formed into an FRP carrier tape after undergoing resin impregnation and curing, as in the embodiments discussed above.

Since this embodiment is the same as the first and second embodiments in that the fabric 1 consists of a braid, with the difference being that the braid of Fig. 8 has a two-dimensional structure, this embodiment has substantially the same advantages as the first and second embodiments. A three-dimensional braid has a better resistance to bending stress, since it can use many thin yarns that are interlaced.

This fabric 1 is woven by a braider having a structure as shown in Figures 9(a) to 9(c). As shown in Figures 9(a) to 9(c), the braider is equipped with a frame 23 having a guide groove 23a for guiding bobbin carriers 22 and two types of horn gears 24 and 25, which drive the bobbin carriers 22. Six small-diameter horn gears 25 are arranged adjacent to one another along an arc, each having four recesses 25a formed at equal angular intervals. The recesses 25a are engageable with the bobbin carriers 22. There are two large diameter horn gears 24, each having five recesses 24a, which are formed at equal angular intervals, identical to the recesses 25a. The recesses 24a are likewise engageable with the bobbin carriers 22. The two horn gears 24 are arranged at such positions as to transfer the bobbin carriers 22 between two legs of a circuit formed by the horn gears 25.

The horn gears 24 and 25 are respectively rotatable by independent actuators (not shown). Each bobbin carrier 22 is designed to engage with the

recesses

24a and 25a of the horn gears 24 and 25 and with the guide groove 23a, and each carrier 22 is movable along the guide groove 23a by the rotation of the horn gears 24 and 25.

The adjacent horn gears 24 and 25 of this braider are continuously rotated in opposite directions at the same peripheral velocity. The bobbin carriers 22 are put in a specific arrangement with respect to the horn gears 24 and 25, as shown in Figure 9(c), and weaving is initiated in this state. When the individual horn gears 24 and 25 are driven in predetermined directions, as indicated by the arrows in Figure 9(c), the moving loci of the yarns in the individual bobbin carriers 22 are shown in Figure 9(d), that is, the yarns 2 fed from the bobbins supported on the bobbin carriers 22 move along the curve shown in Figure 9(d), which represents a path of intersection between the carrier plane and the yarn. As a result, the fabric 1 illustrated in Fig. 8 is woven. That is, a band of fabric 1 having the yarns 2 arranged to be folded back, or turned inward, at the sides is woven.

If holes are formed in the centers of the horn gears 24 and 25 and in the frame 23 at positions corresponding to those centers, and if the braider is driven in the above-discussed manner with core yarns led out of the holes, a fabric 1, as shown in Figure 10, is woven. The band of fabric 1 of Fig. 10 differs from that of Fig. 8 in that the band of Fig. 10 includes core yarns 27 running parallel in the longitudinal direction of the fabric 1. Therefore, a carrier tape using the band fabric 1 of Fig 10 as a reinforcing material has a greater resistance against bending stress and elongation as compared with a carrier tape using the band of fabric 1 of Fig. 8 as a reinforcing material.

The fifth embodiment will now be discussed with reference to Figure 11. In this embodiment, the band of fabric 1 consists of a plain fabric band or a single-layer fabric band. The fabric band 1 is woven with warps Y arranged in the longitudinal direction of the fabric 1 and wefts X inserted in the widthwise direction, crossing the warps Y perpendicularly. When the flat fabric 1 of Fig. 11 is to be formed into a carrier tape with a predetermined rigidity, the individual yarns forming the flat fabric 1 should have a diameter that is approximately equal to the total thickness of a fabric band made of a plurality of layers.

Since the fabric band of Fig. 11 is a single-layer fabric, an FRP carrier tape employing a band of this fabric as a reinforcing material does not suffer interlayer separation. Since the wefts X are folded inward at both sides of the band of fabric 1 (see Fig. 11), there are no cut fiber surfaces present at either side surface of the carrier tape. Even when bending stress is frequently applied to the carrier tape, therefore, the carrier tape resists splitting at its side surfaces.

If the band of fabric 1 is formed of a single-layer cloth, the band may be woven by a tape loom. In the band 1 of Figure 12, the fabric is woven with the warps Y arranged along the longitudinal direction of the fabric band 1 and the wefts X inserted in a folded manner in the widthwise, or transverse, direction, perpendicularly crossing the warps Y. The individual yarns of the warps Y and wefts X should be thick. The advantages of the embodiment of Fig. 11 also result in the embodiment of Fig. 12.

A twill instead of a plain fabric may be used as the single-layer fabric of the band. With the use of a twill, yarns of the same thickness as that of a plain fabric can produce a fabric that is thicker than the plain fabric. It is therefore possible to weave a fabric suitable for a carrier tape having a given rigidity with yarns that are thinner than the yarns of a plain fabric having the same rigidity.

The sixth embodiment will now be described with reference to Figures 13 and 14. The fabric of the band of this embodiment differs from those of the above-described embodiments in that most of the yarns constituting the fabric are first yarns, which have a large modulus of elasticity, and second yarns, which have a larger elongation at their breaking point than the first yarns, are arranged along substantially the entire length of the fabric. While this fabric band 1, like the fabric band 1 of the first embodiment, is formed of a three-dimensional braid, the fabric of Fig. 13 differs in that a plurality of core yarns, which are not part of the three-dimensional braid, are arranged along substantially the entire length of the fabric band 1. The core yarns, or second yarns, are formed of fibers having a greater elongation at their breaking point than the first yarns. To avoid a redundant description, like or same reference numerals are given to those components that are the same as the corresponding components of the first embodiment.

Figure 13 is a schematic perspective view showing a part of a carrier tape 29. The carrier tape 29 is formed of FRP in which the band of fabric 1, which has substantially the same width and thickness as the carrier tape 29, has been subjected to resin impregnation and curing and has holes 31 formed along its center line at a predetermined pitch. The holes 31 are formed in a diamond shape to engage with the teeth of the carrier tape drive sprocket (not shown).

The fabric band 1 of Fig. 13, like that of the first embodiment, is comprised of a rectangular three-dimensional braid. The fabric band 1 includes yarns 2 folded back, or inward, on the surface of the fabric 1 and to have a predetermined alignment angle with respect to the longitudinal axis of the fabric band 1. Furthermore, core yarns 32a, or second yarns, which are not involved in the weave of the three-dimensional braid, run longitudinally in the band of fabric 1. The alignment angle of the first yarns 2 is set to ±45 degrees. Untwisted yarns comprised of fibers, such as carbon fibers or ceramic fibers, are used as the first yarns 2, which have a large modulus of elasticity. Therefore, the first yarns having a large modulus of elasticity are used for most of the yarns that constitute the fabric 1.

At least two core yarns 32a serve as the second yarns. The second yarns 32a are arranged at a predetermined transverse spacing, so that the carrier tape 29 resists twisting when the first yarns 2 of the carrier tape 29 are all broken. In this embodiment, two core yarns 32a are arranged on either side of the row of holes 31. For example, polyaramide fibers or high-strength polyethylene (ultra high molecular weight polyethylene) fibers can be used for the second yarns, or core yarns 32a. Of polyaramide fibers, Kevlar (trade name, available from Du Pont) is preferable.

The fabric 1 is woven with the braider for three-dimensional braid according to the first embodiment(Fig. 2). Each rotor 6 in use has a hole 6a formed in the center, as shown in Figure 14. When the braider for three-dimensional braid is driven in the same manner as in the first embodiment, the core yarns 32a are led out of the holes 6a of the rotors 6 corresponding to their arranged positions, and the fabric band 1 of Fig. 13, with the core yarns 32a arranged at predetermined positions, is woven.

The carrier tape 29 of this embodiment (Fig. 13) has the following advantages in addition to the advantages of the carrier tape of the first embodiment.

An FRP carrier tape that uses, as a reinforcing material, a fabric formed to avoid interlayer separation in a direction perpendicular to the plane of the band may, after a long period of use, be fractured along a plane perpendicular to the longitudinal axis of the tape, if the yarns of the fabric are all formed of the same large modulus of elasticity material. Accordingly, loom beating-up may occur when a part of the carrier tape and the rapier head remain in the weaving section of the loom, after breaking off. Since the core yarns 32a, which have a larger elongation at their breaking point than the yarns 2 that mostly constitute the fabric 1, are arranged along substantially the entire length of the fabric 1, even if the yarns 2 are all broken, the carrier tape 29 is still in one piece due to the core yarns 32a. Therefore, the rapier head and a length of the carrier tape would not be left in the shed during beating-up, thus preventing the rapier loom from being damaged during the beating-up step.

Since at least two core yarns 32a are arranged at a predetermined spacing in the widthwise, or transverse, direction of the carrier tape 29, the carrier tape 29 resists being twisted at locations where the yarns 2 are broken. This prevents the loom warps from being cut by the broken tape when the carrier tape is moved out of the warp opening (shed).

Since at least one core yarn 32a is arranged on either side of the area where each hole 31 is formed, the core yarns 32a are not cut during formation of the holes 31 after subjecting the fabric 1 to resin impregnation and curing treatment. Therefore, the reinforcing fabric 1 can be used for the carrier tape 29, regardless of whether or not the holes 31 are formed in the carrier tape 29.

Since the second yarns, which have a large elongation at their breaking point, are employed, as the core yarns 32a in the fabric 1 at a number of transverse locations extending parallel to the longitudinal axis of the fabric 1, the characteristics of the second yarns have little or no influence on the flexural elasticity of the carrier tape 29. Even when the second yarns have a smaller flexural rigidity than the first yarns, for example, the flexural rigidity of the carrier tape 29 is not significantly reduced.

The seventh embodiment will now be discussed with reference to Figure 15. This embodiment differs from the sixth embodiment in that the second yarns arranged in the fabric three-dimensional braided fabric band 1 are interlaced yarns 32b that are interlaced with a part of the first yarns 2, not as core yarns 32a. As shown in Figure 15, the interlaced yarns 32b, or second yarns, are woven with the first yarns 2 as to be folded back, or angled inward, near the surface of the fabric band 1. The interlaced yarns 32b are interlaced in both the top and bottom surfaces, or the wide surfaces.

In weaving this fabric band 1, a braider for three-dimensional braid is used, as in the sixth embodiment. The three-dimensional braid is woven with the braider for three-dimensional braid by separately driving two groups of multiple rotors 6 as described earlier. By pausing some of the driven rotors 6, the reversing positions of the yarn carriers 4 can be altered so that weaving can be carried out with the reversing positions of specific yarns set different from those of the other yarns. Therefore, the fabric band 1 is woven (interlaced) with the yarns 2 in such a manner that the interlaced yarns 32b are folded back, or angled, only near the surface of the fabric band 1. This is accomplished by setting bobbins carrying the second yarns onto predetermined yarn carriers 4 that move in paths different from those of the yarn carriers 4 that support the bobbins carrying the first yarns 2. When weaving the fabric band 1 of this embodiment (Fig. 15), the core yarns 32a are unnecessary so that no holes 6a in the centers of the rotors 6 are needed. Therefore, the structure of the braider for three-dimensional braid is simpler for the band 1 of Fig. 15 than that used for the band 1 of Fig. 13.

The FRP carrier tape manufactured by using the fabric band 1 of Fig. 15 as a reinforcing material has the same advantages as that of the sixth embodiment, except for the advantage resulting from the use of the core yarns 32a. Since the second yarns are interlaced with the first yarns in the band 1 of Fig. 15, the force required to pull out the second yarns from the fabric 1 is greater as compared with a band where the second yarns are simply inserted in the fabric 1 like the core yarns 32a. Accordingly, when the first yarns 2 are broken, the interlaced second yarns 32b do not come out of the fabric 1.

Although seven embodiments of the present invention have been described herein, it should be apparent to those skilled in the art that the present invention may be embodied in many other specific forms without departing from the spirit or scope of the invention. Particularly,it should be understood that the present invention may be modified to the forms described below.

(1) When a two-dimensional braid is used for a fabric, a round braid may be used in place of a flat braid. The round braid is formed by a braider having a structure as illustrated in Figures 16(a) to 16(c). The round braid significantly differs from the flat braid in that one type of horn gears 25 (eight in Figure 16(a)) are arranged adjacent to one another in such a manner that their rotational centers are positioned on the same circle. The guide groove 23a is symmetrical about several planes, each of which is aligned with the center axis. Each horn gear 25 has four recesses 25a formed at equal intervals, which engage with the bobbin carriers 22. The horn gears 25 are respectively rotatable by independent actuators (not shown), and each bobbin carrier 22 can be moved along the guide groove 23a by the rotation of the horn gears 25 while being engaged with the recesses 25a of the horn gears 25. The adjoining horn gears 25 are continuously rotated in opposite directions at the same peripheral velocity. The bobbin carriers 22 are placed in a specific arrangement with respect to the individual horn gears 25 as shown in Figure 16(c), and weaving is started in this state. When the individual horn gears 25 are driven in predetermined directions (indicated by the arrows in Figure 16(c)), the moving paths of the individual yarns of the bobbin carriers 22 are as shown in Figure 16(d). That is, the yarns 2 released from the bobbins supported on the bobbin carriers 22 move along the curves shown, in Figure 16(d). Therefore, the woven braid to be woven is formed into a cylindrical (tubular) shape.When a cylindrical round braid is used as a reinforcing material, resin impregnation and curing treatment is performed with the cylinder pressed and doubled into a flat braid. A carrier tape formed in this manner can be thrust into and out of the shed in accordance with the rotation of the rapier wheel while being held horizontally without using guide members. Because no cut fiber surfaces are present the sides of the carrier tape, this carrier tape is more durable than the conventional FRP carrier tape having laminated fibers as a reinforcing material.With the round braid simply pressed, there is a clear interface between layers at the middle, so that repeated application of bending stress is likely to cause interlayer separation. Such interlayer separation may be prevented by sewing stitch yarns into the pressed round braid in the thicknesswise, or top to bottom, direction by a sewing machine to form a fabric band. In this case, the fabric approximates a three-dimensional rectangular fabric band and has the same advantages as that of the third embodiment.

(2) Three-dimensional fabrics as disclosed in Japanese Patent Publication No. Sho 54-38673 and Japanese Unexamined Patent Publication No. Sho 61-245335 may be used as the three-dimensional fabric that constitutes the fabric band 1. As shown in Figure 17, this kind of three-dimensional fabric is woven by sequentially inserting first wefts x between the columns of warps y stretched in rows and columns, in a folded form, and perpendicular to the warps y. The wefts x are locked by lock yarns P1. Then, second wefts z are sequentially inserted between the rows of the warps y in a folded form and perpendicular to the warps y. Further, a three-dimensional fabric as disclosed in Japanese Unexamined Patent Publication No. Hei 4-11042 may he used as well, which is woven by sequentially inserting first and second wefts between the rows and columns of warps stretched in rows and columns, in a folded form, perpendicular to the warps, and inserting bias yarns between the rows of the warps obliquely with respect to the warps. When such three-dimensional fabric band is used as the fabric 1, it has substantially the same advantages as that of the third embodiment.

(3) When a three-dimensional braid is used as a fabric, it is not limited to a type in which all the yarns constituting the fabric are folded back at each surface of the fabric, but a three-dimensional braid containing yarns arranged in the lengthwise direction of the fabric may be used as well. This braid is formed by forming holes in the centers of the rotors 6 and driving the braider for three-dimensional braid with fixed yarns (core yarns) led out of the holes in the same manner as described earlier. A carrier tape using this fabric has improved strength against bending stress, or tensile stress, because of the core yarns running straight and parallel along the longitudinal direction of the fabric band.

(4) The fabric band may be formed by knitting.

(5) Instead of weaving the fabric band with yarns of a single material, for example, carbon fibers, the fabric band may be formed by weaving yarns of different types of fibers. The fabric band may be woven with yarns of different thicknesses, instead of yarns of the same thickness. With yarns of various thicknesses, it is easy to adjust the strength and rigidity of the fabric band.

(6) When the second yarns are arranged as the interlaced yarns 32b in the seventh embodiment, the second yarns may be positioned at both sides of the fabric band 1 as shown in Figure 18, or may be positioned on both top and bottom surfaces of the fabric 1 and at both sides. Further, the fabric 1 may contain both the core yarns 32a and the interlaced yarns 32b as shown in Figure 19. In either case, the fabric 1 has the same advantages as that of the seventh embodiment.

(7) when two or more second yarns are arranged in the fabric 1, they are not limited to positions symmetrical to the center of the fabric 1, but may be arranged at other appropriate positions. The second yarns may be arranged at positions that permit twisting of the carrier tape when the first yarns are broken. In that case, a single second yarn is sufficient. When the carrier tape is twisted when the first yarns are broken, the loom warps may be broken when the carrier tape is retracted from the shed, but damage to the loom resulting from beating-up with a part of the carrier tape remaining in the shed will be prevented.

(8) When the fabric 1 is comprised of a three-dimensional braid, as shown in Figure 20, the alignment angle of the yarns 2 in an area A1 where holes 31 are formed may be set greater than the alignment angle in areas A2 to the sides of the area A1. In this case, the durability of the carrier tape 29 is improved as compared with a band where the yarns 2 are arranged at the same alignment angle over the entire area.

(9) To prevent the carrier tape from being completely broken, a three-dimensional fabric may be used in place of a three-dimensional braid if the basic structure of the fabric is such that second yarns, which have a large elongation at their breaking point, are arranged along substantially the whole length of the fabric. As the three-dimensional fabric, that of the third embodiment or that described in the paragraph (1) is used. When a three-dimensional fabric similar to that of the third embodiment is used, the desired fabric can be manufactured by arranging the second yarns to extend at predetermined locations in the longitudinal direction of the three-dimensional fabric, together with the first yarns that are arranged in an angled manner in the longitudinal direction of the three-dimensional fabric. When a three-dimensional fabric similar to the one described in paragraph (1) is used, the desired fabric can be manufactured by arranging the second yarns to extend as a part of the warps y. In such a case, the resultant fabric has the advantages of the sixth embodiment, except for the advantage resulting from the structure of the three-dimensional braid. When a fabric band consisting of a three-dimensional fabric is used as a reinforcing material, unlike the fabric 1 consisting of a three-dimensional braid, the fabric has yarn layers (fiber layers) that can separate in a direction perpendicular to the plane of the fabric. When bending stress is frequently applied to the carrier tape, therefore, interlayer shear fracture or surface peeling may occur locally. However, the progress of interlayer separation is inhibited by the individual yarn layers connected by yarns that penetrate the yarn layers thicknesswise, or top to bottom. The durability is thus greater than that of a conventional carrier tape that has laminated fiber layers and has no yarns penetrating the layers that would resist interlayer separation.

(10) A further fabric band consisting of a two-dimensional flat braid having multiple first yarns with second yarns arranged as core yarns can be used as reinforcement fabric. Since the two-dimensional braid, unlike a three-dimensional braid, has only two first yarns arranged in the thicknesswise direction of the fabric, it is not possible to increase the number of fibers arranged in the thicknesswise direction to ensure the desired rigidity. However, the desired rigidity can be achieved by varying the thickness of the yarns. This fabric is formed into an FRP carrier tape by performing resin impregnation and curing as in the individual embodiments described above. Since this case is like the sixth embodiment in that the fabric consists of a braid, with the difference that the braid has a three-dimensional structure instead of a two-dimensional one, this fabric has substantially the same advantages as that of the sixth embodiment. To ensure a predetermined rigidity, the three-dimensional braid can use multiple thin interlaced first yarns and thus has a better resistance against bending stress.

(11) A further fabric band maybe formed by sewing stitch yarns into a flattened round braid in the thicknesswise direction by a sewing machine. In addition, there are longitudinal, parallel core yarns located within the braid. In this case, the fabric band substantially becomes a three-dimensional fabric band and has the same advantages as those described in the previous paragraph (10).

(12) A further fabric band may be formed with second yarns replacing some of the warps of a single-layer flat fabric, which is woven by a small-width loom or a tape loom.

(13) In the case where the second yarns are interlaced with the first yarns in a three-dimensional braid, the second yarns may be folded back over the entire area outside the area where holes of the carrier tape are formed, instead of being folded back near the surface of the three-dimensional braid.

(14) The hole 31 are not limited to a diamond shape, but may be formed in various other arbitrary shapes, such as a rectangular shape, a polygonal shape, a circular shape and an elliptical shape. It is however preferable to form the holes 31 in a diamond shape where they are formed in a mold.

(15) This invention may be adapted to a carrier tape having no holes.

Therefore, the present examples and embodiments are to be considered as illustrative and not restrictive and the invention is not to be limited to the details given herein, but may be modified within the scope and equivalence of the appended claims.

Claims

An elongated fiber reinforced plastic carrier tape for use in a rapier loom, comprising:

a fabric band (1), which is substantially the same size as said carrier tape, as a reinforcing material for reinforcing the tape, said fabric band (1) including a yarn (2) arranged obliquely to a longitudinal direction of said fabric band, said yarn (2) being woven to be folded at the sides of said fabric band (1).
The carrier tape according to claim 1, wherein said fabric band (1) is an interconnected integral fabric.
The carrier tape according to claim 1 or 2, wherein said fabric hand (1) is a three-dimensional braid.
The carrier tape according to claim 1, wherein said fabric band (1) is a three-dimensional fabric.
The carrier tape according to claim 1 or 2, wherein said fabric band (1) is a two-dimensional flat braid.
The carrier tape according to claim 1 or 2, wherein said fabric band (1) is a flattened round braid, wherein the flattened braid is sewn in place.
The carrier tape (29) according to claim 1 or 2, wherein said fabric band (1) is a single-layer fabric.
The carrier tape (29) according to claim 2, further comprising:

a first yarn with a large modulus of elasticity, wherein most of said yarn (2) constituting said fabric band is of the first yarn; and

at least one second yarn arranged along substantially the entire length of said fabric band (1), wherein the second yarn has a greater elongation at its breaking point than said first yarn.
The carrier tape (29) according to claim 8, wherein at least two second yarns are arranged at predetermined locations, spaced apart in a widthwise direction of said carrier tape (29), to prevent twisting of said carrier tape when said first yarn is broken.
The carrier tape (29) according to claim 9, wherein said carrier tape has holes (31) engageable with teeth formed in a carrier tape drive sprocket of said rapier loom, and at least one second yarn is arranged on either side of a longitudinal area where said holes (31) are formed.
The carrier tape (29) according to any one of claims 8 to 10, wherein said fabric band (1) is a three-dimensional braid.
The carrier tape (29) according to any one of claims 8 to 10, wherein said second yarn is arranged in said fabric band (1) as a core yarn (32a) extending in the longitudinal direction of said fabric band (1).
The carrier tape (29) according to claim 11, wherein said second yarn is arranged in said fabric band (1) as a core yarn (32a) extending in the longitudinal direction of said fabric band.
The carrier tape (29) according to claim 11, wherein said second yarn is interlaced to form fibers of the three-dimensional braid.
A fabric band (1) used as a reinforcing material for reinforcing band-like fiber reinforced plastic in a carrier tape of a rapier loom, said fabric band (1) having approximately the same cross sectional shape as said carrier tape, said fabric band (1) including a yarn (2) arranged obliquely to a longitudinal direction of said fabric band, said yarn (2) being woven to be folded at the sides of said fabric band (1).
The fabric band (1) according to claim 15, wherein:

said yarn (2) constituting said fabric band (1) is an interconnected integral fabric;

the band (1) includes a first yarn with a large modulus of elasticity, wherein most of said yarn constituting said fabric band (1) is of the first yarn; and

at least one second yarn is arranged along substantially the entire length of said fabric band, and the second yarn has a larger elongation at its breaking point than said first yarn.
The fabric band (1) according to claim 15, wherein said fabric band (1) is a three-dimensional braid.
The fabric band (1) according to claim 15, wherein said fabric band (1) is a three-dimensional fabric.
The fabric band (1) according to claim 15, wherein said fabric band (1) is a two-dimensional flat braid.
The fabric band (1) according to claim 15, wherein said fabric band (1) is a flattened round braid, wherein the flattened braid is sewn in place.
The fabric band (1) according to claim 15, wherein said fabric band (1) is a single-layer fabric.
The fabric band (1) according to claim 16, wherein at least two second yarns are arranged at predetermined locations, spaced apart in a widthwise direction of said fabric band (1).
The fabric band (1) according to claim 17, wherein at least one second yarn is arranged on either side of a longitudinal area where holes engageable with teeth are formed in a carrier tape drive sprocket of said rapier loom.
The fabric band (1) according to claim 16, 22 or 23, wherein said fabric band (1) is a three-dimensional braid.
The fabric band (1) according to claim 16, 22 or 23, wherein said second yarn is arranged in said fabric band (1) as a core yarn (32a) extending in the longitudinal direction of said fabric band.
The fabric band (1) according to claim 24, wherein said second yarn is interlaced to form fibers of the three-dimensional braid.