JPH11200235A - Device for cutting hollow yarn knit fabric - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device for cutting a hollow yarn knit fabric, capable of surely closing the inner cavities of the hollow yarns in a process for cutting the hollow yarn knit fabric, inhibiting the intrusion of a resin from the end openings of the hollow yarns into the hollow cavities, and reducing the closed portions of the knit fabric to decease the waste of the knit fabric. SOLUTION: A hollow yarn knit fabric 1 is carried between upper and lower endless belts 12, 12 driven with driving pulleys 11, 11, 11, 11 in a state that the inner cavities 2a of the hollow yarns 2 are flatly pressed and held. A fusing means 13 having an ultrasonic fusing machine 13a and an anvil 13c, a roller 14 for controlling a fused thickness, and a means 15 for cooling a knit fabric are arranged in the carrying route of the belts 12, 12. The knit fabric 1 is subjected to an ultrasonic fusing treatment, a thickness control treatment and a cooling and setting treatment in a state held with the belts 13. The approximately center of the fused portion of the knit fabric 1 is cut with a cutting means disposed on the downstream side.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cutting apparatus for cutting a knitted fabric containing a hollow fiber used for a heat exchange module or the like across a hollow portion inside the hollow fiber, and more particularly, to cutting the hollow fiber. The present invention also relates to a cutting device for closing the cut end. In this specification, “hollow fiber” refers to a hollow fiber having a non-porous structure, a hollow fiber having a porous structure, a composite hollow fiber in which a non-porous layer and a porous layer are combined, and the like.

[0002]

2. Description of the Related Art When a hollow fiber is used in, for example, a heat exchange module, a filtration module, a degassing module, and the like, usually, the hollow fiber is used as a weft and a yarn such as a polyethylene multifilament is used as a warp to form a hollow fiber. Knitted on the ground,
The hollow fiber knitted fabric is used after being cut into a desired size according to the application. Conventionally, a rotary blade that rotates in the cutting direction is used for cutting the hollow fiber knitted fabric. When the hollow fiber knitted fabric is cut in a direction transverse to the internal cavity of the hollow fiber by such a rotary blade, the internal cavity is opened at the cut end, and the internal cavity of the hollow fiber extends over the entire length. Communication with the outside.

By the way, for example, when a cut hollow fiber knitted fabric piece as described above is used for a heat exchange module,
In such a heat exchange module, a predetermined amount of the hollow fiber knitted fabric pieces are further bundled into a container and placed in a container, and the hollow fibers are opened at the cut ends of the knitted fabric pieces so that the hollow fibers are opened. Only the periphery is fixed with resin, and the heated fluid side and the non-heated fluid side are partitioned in such a manner that the internal space of the hollow fiber is communicated. At the time of fixing the resin, as described above, the cut end of the hollow fiber knitted fabric piece has the internal cavity of the hollow fiber opened, so that the resin enters the internal cavity from the opening at the same end. However, the resin hardens and the end is completely closed. In that case, it becomes impossible for the fluid to enter and exit from the hollow fiber opening at the end, and it becomes impossible to function as a heat exchange module. Waste of resin increases.

[0004] Therefore, before the resin is fixed, the cut end of the hollow fiber knitted fabric piece is closed in advance to prevent the resin from entering the internal cavity, thereby reducing the waste of the hollow fiber and the resin. However, since the temporary closing of the cut end was conventionally performed in a separate step, it took time for the temporary closing step, which was one of the factors of cost increase.

[0005] For example, Japanese Utility Model Laid-Open No. 6-63127 discloses a hollow fiber knitting apparatus for cutting a hollow fiber knitted fabric in which a cutting step is closed in the hollow fiber knitted fabric cutting process to reduce the working time. Is disclosed. The cutting device is arranged opposite to the conveying roller of the hollow fiber knitted fabric, and has a pressing roller that rotates in the same direction as the conveying roller and has two continuous ridge pressing portions at both ends, respectively. The knitted fabric is pressure-bonded by a ridge pressing portion. Therefore, two sets of two crimping portions are formed on the knitted fabric with a gap provided therebetween.
Further, a cutting means such as a heating element is arranged downstream of the pressure roller in proximity to the roller, and the knitted fabric is cut at an unpressed portion between the two sets of the pressure-bonded portions.

[0006]

In the cutting apparatus disclosed in the above-mentioned publication, the hollow fiber knitted fabric may be heated and press-bonded by heating the pressure roller to melt and pressure-bond.
In some cases, pressure bonding is performed only by applying pressure. If the pressing force is weak, the internal cavity of the hollow fiber may not be completely closed if the pressing force is weak. It is desirable to use a set of crimping parts. However, by forming a pair of crimping portions, the crimping portion becomes wide, and furthermore, since the crimping portion is provided at a portion away from the cut end portion, a portion to be cut off after being fixed with the resin is not provided. It gets bigger. In addition, since it is cut at an uncompressed portion, the internal cavity of the hollow fiber is open at the cut end, and the resin also enters the cut end which is cut off later when fixing the same end with resin. As a result, waste of resin increases.

Accordingly, the present invention is to completely and surely close the end opening of the hollow fiber internal cavity at the cut end in the cutting step of the hollow fiber knitted fabric, and to prevent the resin from entering the internal cavity from the end surface opening. It is an object of the present invention to provide a cutting device for a hollow fiber knitted fabric, which reduces waste of resin by eliminating the same and reduces the area of a closed portion of the knitted fabric, thereby reducing waste of the knitted fabric.

[0008]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a method of cutting a hollow fiber knitted fabric using a thermoplastic hollow fiber as a weft in a warp direction. An endless belt that continuously conveys the hollow fiber knitted fabric in the warp direction, a conveyance pulley that drives the endless belt, and a predetermined portion of the hollow fiber of the knitted fabric that is continuously welded. Welding means for closing the internal cavity, a welding thickness adjusting roller disposed above and below the hollow fiber knitted fabric on the downstream side of the welding means and adjusting the thickness of a welded portion of the knitted fabric, and the welding thickness adjustment A hollow fiber, comprising: a knitted fabric cooling unit disposed downstream of a roller; and a cutting unit disposed downstream of the knitted fabric cooling unit and configured to cut the knitted fabric at the welded portion. Mainly knitted fabric cutting device It is an object of such.

It is preferable that the endless belt is disposed above and below the knitted fabric with the hollow fiber knitted fabric interposed therebetween.
It is preferable that the welding unit, the welding thickness adjusting roller, and the knitted fabric cooling unit are arranged in a conveyance path by the endless belt.

[0010] The welding means may include an ultrasonic welding machine and an anvil which are arranged facing each other through the endless belt, or the welding means may be arranged facing each other via the endless belt. And a pair of heating devices.

Further, when the welding thickness adjusting roller has a plurality of thickness adjusting ridges at both ends, the welding is more reliably performed.

The hollow fiber cutting device having the above-described configuration is combined with various mechanisms such as a raw fabric feeding mechanism, a meandering adjusting mechanism, a static electricity removing mechanism, a dust removing mechanism, and a winding mechanism as necessary, By interlocking these, a hollow fiber knitted fabric piece cut in a state in which the ends are welded from the hollow fiber knitted fabric can be continuously obtained.

When cutting the hollow fiber knitted fabric, first, the hollow fiber knitted fabric is fed out of the raw fabric by the raw fabric feeding mechanism, and the running posture of the hollow fiber knitted fabric of the present invention described above is appropriately maintained by the meandering adjusting mechanism. It is sent to the yarn cutting device. In the apparatus, the knitted fabric is conveyed while being sandwiched from above and below by the endless belt driven by the plurality of conveyance pulleys. While the knitted fabric is being conveyed by the endless belt, the knitted fabric is melted in a state where the peripheral wall portion of the hollow fiber is pressed by the welding means arranged vertically above and outside the endless belt so that the peripheral wall portion is vertically and closely contacted. Then, the inner wall is closed by vertically welding the peripheral wall portion. The welded portion in the molten or semi-molten state passes through the weld thickness adjusting means to adjust the weld thickness to a desired size, and is further cooled by the knit fabric cooling means to cool the welded part in the molten or semi-molten state. The hollow fiber is securely welded. Thereafter, the welded portion is cut by a cutting means to obtain a hollow fiber knitted fabric piece.

It is to be noted that one of the welding means arranged up and down via the endless belt is fixed, and the other can be raised and lowered by an air cylinder.
It is desirable to be able to arbitrarily set the distance between the vertically movable welding means and the knitted fabric and to have a mechanism for maintaining the distance. Thereby, the position of the welding means that can move up and down can be appropriately set according to the thickness of the knitted fabric and welding conditions, and the knitted fabric can be appropriately melted by the welding means.

Further, according to the present invention, the welding thickness adjusting roller composed of a pair of upper and lower rollers is disposed downstream of the welding means in the conveyance path of the endless belt, and the gap between the upper and lower rollers is knitted. Each roller is fixed at a position where the welded portion of the ground has a desired thickness.
Therefore, the knitted fabric passes through the gap between the rollers while being sandwiched between the upper and lower endless belts, the weld thickness is adjusted, and the knitted fabric has a uniform weld thickness over the entire length.

Further, the knitted fabric whose weld thickness has been adjusted,
It passes through a cooling device arranged downstream of the welding thickness adjusting means in the conveying path of the endless belt while maintaining its shape, and the welded portion in a molten or semi-molten state is cooled and solidified.

In this state, the knitted fabric is completely conveyed by the endless belt, and is sent further downstream by, for example, a conveying roller. Thereafter, the knitted fabric was cut at substantially the center of the welded portion by a cutting means provided to cut a portion corresponding to the center of the welding means, and further, static electricity and dust were removed and cleaned in the next step. Thereafter, the whole is wound up to a predetermined amount and the entire process of forming the hollow fiber knitted fabric piece is completed.

Since the hollow fiber knitted fabric piece cut by such a device is cut at substantially the center of the welded portion as described above, the internal cavity of the hollow fiber is completely closed at the end surface at the cut end. . Therefore, the resin does not enter the internal cavity even when the cut end is fixed with a resin for later incorporation into, for example, a heat exchange module, and waste of the resin can be reduced. Further, by setting the width of the welded portion small within a range that can be cut later, the number of welded portions cut off after fixing the resin is reduced, and the amount of resin used can be further reduced.

Further, after the hollow fiber knitted fabric is welded while being held vertically by the endless belt as described above, the thickness of the weld is adjusted and further cooled and fixed, so that the internal cavity is securely closed. can do. Also, since the thickness of the cut end is uniform during the operation of fixing the resin,
When a plurality of the knitted fabric pieces are stacked or wound in a roll, the hollow fibers are arranged at uniform intervals.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to typical illustrated embodiments. FIG. 1 is a schematic view of an apparatus for cutting a hollow fiber knitted fabric according to a typical embodiment of the present invention, FIG. 2 is a front view of welding means in the apparatus,
FIG. 3 is a side view of the same. 4 to 6 are a plan view, a side view, and a cross-sectional view of a hollow fiber knitted fabric in the middle of the transportation of the device. The hollow fiber knitted fabric 1 is made of polyethylene non-porous hollow fibers 2 having internal cavities 2a as wefts, and polyethylene multifilaments 3 are arranged at predetermined intervals as warp yarns, and are knitted in a slender shape. . Such knitted fabric 1
Is cut into a desired width later, and the welded portion 4 is formed in advance in the cut portion.

The cutting apparatus 10 according to the present embodiment includes a pair of upper and lower endless belts 12 stretched over a plurality of drive pulleys 11 as a means for transporting the hollow fiber knitted fabric 1. The endless belt 12 is made of a reinforced fabric or the like, and a surface that comes into contact with the knitted fabric 1 is coated with a resin having good releasability. The endless belts 12 are arranged at a plurality of locations in the width direction of the hollow fiber knitted fabric 1 including at least a portion to be cut of the knitted fabric 1. The two belts 12 and 12 are positively driven in the same direction in a pressurized state by the driving pulley 11, and the knitted fabric 1 is gripped between the belts 12 and the hollow fibers 2 are
Is transported in a state where the internal cavity 2a is crushed. By arranging a plurality of sets of the endless belts 12 in the width direction of the knitted fabric 1, the knitted fabric 1 is gripped at a plurality of locations and is conveyed at the same speed, so that the conveying posture of the knitted fabric 1 is disturbed. And stable transport is possible.

Further, the cutting device 10 is provided with a welding means 13, a welding thickness adjusting roller 14, and a cooling means 15 in the conveying path of the endless belt 12 in order from the upstream side.

The welding means 13 includes an ultrasonic welding machine 13a and an anvil 13c. The ultrasonic welding machine 13a and the anvil 13c are arranged vertically with the endless belt 12 interposed therebetween. The horn 13 of the ultrasonic welding machine 13a disposed on the upper side of the endless belt 12
The width of the leading end of b is processed to the welding width of the knitted fabric 1, and this welding width is set as small as possible within a range where the center of the welded portion 4 of the knitted fabric 1 can be cut by cutting means later. I have. For this reason, when the cut end is fixed to the resin later to manufacture, for example, a heat exchange module, the welded portion 4 to be cut becomes small, so that the amount of resin used can be significantly reduced.

The upstream edge and the downstream edge of the front end of the horn 13b are subjected to R-surface processing or the like to reduce the resistance when the endless belt 12 runs. Further, the horn 13b of the ultrasonic welding machine 13a can be moved up and down by an air cylinder (not shown), and the welding machine 13a has a function of adjusting and holding the lowered position of the horn 13b. On the other hand, the anvil 13c has a cylindrical shape, and rotates synchronously in the same direction as the traveling direction of the endless belt 12.

In this embodiment, an ultrasonic welding machine 13a and an anvil 13c are used as the welding means 13. Although not shown, for example, a heating welding device provided with a heating plate, a heating roller and the like is used. It is also possible.

The welding thickness adjusting rollers 14 are vertically arranged with the endless belt 12 interposed therebetween. When passing between the rollers 14, the thickness of the welded portion of the knitted fabric 1 is reduced to the gap between the rollers 14. Adjusted. Therefore, the thickness of the welded portion of the knitted fabric 1 becomes uniform over its entire length, and the thickness can be adjusted with high accuracy. In order to more reliably weld the welded portion, a plurality of thickness adjusting protrusions may be provided at both ends of the roller peripheral surface of the weld thickness adjusting roller 14.

The cooling means 15 are arranged above and below the endless belt 12, respectively. The cooling means 15 includes a metal plate, and a blower 15a for blowing cold air toward the metal plate, disposing the metal plate in close contact with the endless belt 12, and cooling the metal plate cooled by the blower 15a. The heat transfer cools the knitted fabric 1 transported between the endless belts 12.

Further, the cutting device 10 is provided with cutting means (not shown) such as a rotary blade, scissors, and score cut on the downstream side of the conveying path of the endless belt 12. Furthermore,
It is also possible to install a static eliminator or a cleaner on the downstream side of the cutting means to remove static and remove chips and the like.

Hereinafter, the process of cutting the hollow fiber knitted fabric 1 using the above-described cutting device 10 will be described. First,
The raw material of the hollow fiber knitted fabric 1 knitted to have a width larger than a desired width and formed into a predetermined amount is set in a holder of an unwinding device (not shown), and an appropriate tension is set in accordance with the knitting fabric transport speed. And unwinding. The unwinding tension at this time is adjusted according to the number and strength of the warps and the strength of the hollow fibers. The unwound knitted fabric 1 is then sent to a meandering adjustment device (not shown), and is conveyed in an appropriate running posture while continuously adjusting the position in the width direction. It is pulled between the endless belts 12,12.

The knitted fabric 1 drawn between the endless belts 12 and 12 is gripped by the belt 12 in a state where the internal cavity 2a of the hollow fiber 2 is flatly crushed, and the downstream side is maintained while maintaining its shape. To the welding means 13.

In the welding means 13, the knitted fabric 1 is introduced between the horn 13b and the anvil 13c of the ultrasonic welding machine 13a while being held by the upper and lower endless belts 12. Then, compressed air is supplied to an air cylinder of the ultrasonic welding machine 13a to lower the horn 13b, and the welded portion of the knitted fabric 1 is held between the horn 13b and the anvil 13c via the endless belt 12.
At this time, since the ultrasonic welding machine 13a has a function of adjusting and holding the lowered position of the horn 13b by the air cylinder, it is necessary to accurately stop the horn 13b at a predetermined position and hold the position. Can be.

After the horn 13b is stopped at a predetermined position, the ultrasonic welding machine 13a is transmitted to the knitted fabric 1a.
Heat. The heated knitted fabric 1 reaches the melting point and is in a molten or semi-molten state, and the inner transport surface of the endless belt 12 passing through the gap between the tip of the horn 13b and the anvil 13c causes a gap between the transport surfaces. Is flattened. The gap size between the horn 13b and the anvil 13c is determined when the inner cavity 2a of the hollow fiber 2 is flattened between the endless belts 12 and the upper and lower walls of the hollow fiber 2 are in close contact with each other. It is set to a value that is slightly less than the sum of the wall thickness,
Thereby, welding can be performed while maintaining the form of the knitted fabric 1, and the upper and lower wall portions of the hollow fiber 2 are welded and integrated, thereby closing the internal cavity 2a. The horn 13
By holding the lowered position of b, the end of the horn 13b does not press the hollow fiber 2 more than necessary, so that the endless belt 12 can easily travel between the horn 13b and the anvil 13c.

On the knitted fabric 1 having passed through the welding means 13, a welded portion 4 is formed at a predetermined position along the running direction of the knitted fabric 1. The knitted fabric 1 on which the welding portion 4 is formed further passes between the upper and lower rollers 14 of the welding thickness adjusting roller 14 installed on the downstream side of the welding means, and the thickness of the welding portion 4 is reduced. The gap between the rollers 14 is readjusted. In this way, the welding portion 4 welded to a desired thickness by the welding means 13 is again adjusted by the welding thickness adjusting roller 14 so that the thickness can be adjusted with higher precision, and the thickness can be adjusted over the entire length. Can be made uniform.

The knitted fabric 1 whose thickness has been accurately adjusted is conveyed to the knitted fabric cooling means 15 while the shape of the welded portion 4 is maintained by the endless belt 12. The knitted fabric cooling means 15 attaches the blower 15a to the endless belt 12 which grips and transports the knitted fabric 1.
The metal plate cooled by the above is brought into close contact. Thereby,
The welded portion 4 in the molten or semi-molten state of the knitted fabric 1 is heat-transfer cooled through the endless belt 12, and the welding step is completed.

The hollow fibers 2 in the knitted fabric 1 generally have high rigidity and resilience to pressurization, though depending on the wall thickness thereof. , Which is easily restored to the state of
It becomes difficult to completely block a. However,
In the cutting device 10 of the present invention, as described above, in a series of welding steps of the hollow fiber knitted fabric 1, the hollow fiber 2 of the knitted fabric 1 is always pressurized and flattened by the endless belt 12, and the inside of the hollow fiber 2 In a state where the cavity 2a is crushed, it quickly passes through the steps of welding, thickness adjustment and cooling, and after being securely set in the cooling step, it is released from being gripped by the endless belt 12. ,
The hollow fiber 2 does not return to the original shape, and the welding is reliably performed.

After being welded, the knitted fabric 1 is carried out of the conveying path of the endless belt 12 and cut at substantially the center of the welded portion 4 by cutting means (not shown) arranged on the downstream side. At this time, the welded portion 4 of the knitted fabric 1 is cooled by the cooling means and set in a plate shape, so that the cutting becomes easy. The cut hollow fiber knitted fabric piece is neutralized by a static eliminator, and chips and the like are removed by a cleaner. Then, the cut piece is wound around a predetermined bobbin to complete the cutting process of the knitted fabric 1.

Since the hollow fiber knitted fabric piece cut by the apparatus 10 is cut substantially at the center of the welded portion 4 as described above, the internal cavity 2a of the hollow fiber 2 is completely cut off at the cut end. Is closed. Therefore, later
For example, when fixing the cut end portion with a resin in order to manufacture a heat exchange module, the resin does not enter the internal cavity 2a, so that the waste of the resin can be reduced. Furthermore, since the welded portion 4 has a uniform thickness, even when a plurality of the knitted fabric pieces are stacked or rolled in the production of the heat exchange module, the hollow fibers 2 are arranged at uniform intervals. The Rukoto. Further, since the width of the welded portion 4 is made as small as possible so that it can be cut later, the amount of the welded portion 4 cut off after fixing the resin is reduced, and the amount of resin used is significantly reduced. Is reduced.

[Example] A polyethylene hollow fiber having an outer diameter of 0.58 mm and an inner diameter of 0.43 mm was used for the weft, and 2 mm for the warp.
The hollow fiber knitted fabric knitted so that the wefts are formed in a parallel state in a parallel state using a 0d / 10f polyethylene multifilament is cut into the hollow fiber knitted fabric cutting device 10 described above.
By welding. The endless belt 12 of the device 10 has a Teflon coating on the surface of the reinforced fabric, and the belt 12 has a thickness of 0.25 m.
m and a width of about 20 mm were used.

The ultrasonic welding machine 13a having a power of 700 W is used, and the horn 13b is lowered to bring the inner conveying surfaces of the endless belt 12 into contact with each other.
The horn 13b was held at a raised position so that the distance between the conveying surfaces of the two belts 12 was 0.14 mm, and the pressure applied by the air cylinder was set to about 180 Kpa. The output of the oscillator of the ultrasonic welding machine 13a was adjusted to about 20%, and welding was performed by continuous transmission while cooling the ultrasonic welding machine 13a with air. Thereafter, the thickness of the welded portion was adjusted, and the hollow fiber knitted fabric piece obtained by cutting after further cooling and setting was such that the hollow fiber at the cut end was welded to a uniform thickness, and the internal cavity was completely closed. Was.

[0040]

As described above, when the cutting apparatus of the present invention is used, in the cutting step of the hollow fiber knitted fabric, the hollow fiber can be welded at the cut end thereof, and the heat exchange module and the like are later used. Since there is no need to close the cut end in a separate step during manufacturing, the manufacturing efficiency is improved. Also,
The cut end is reliably welded with a uniform thickness along its length direction, the width required for the welded portion is small, and material waste is reduced.

[Brief description of the drawings]

FIG. 1 is a schematic view of an apparatus for cutting a hollow fiber knitted fabric according to a representative embodiment of the present invention.

FIG. 2 is a front view of a welding means in the apparatus.

FIG. 3 is a side view of a welding means in the apparatus.

FIG. 4 is a plan view of a hollow fiber knitted fabric in the process of being transported by the device.

FIG. 5 is a side view of the hollow fiber knitted fabric.

FIG. 6 is a cross-sectional view of the hollow fiber knitted fabric.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hollow fiber knitted fabric 2 Polyethylene hollow fiber 2a Internal cavity 3 Polyethylene multifilament 4 Welding part 10 Cutting device 11 Drive pulley 12 Endless belt 13 Welding means 13a Ultrasonic welding machine 13b Horn 13c Anvil 14 Welding thickness adjusting roller 15 Cooling means 15a blower

Claims (6)

[Claims] An apparatus for cutting a hollow fiber knitted fabric using a thermoplastic hollow fiber as a weft in a warp direction, wherein the hollow fiber knitted fabric is continuously conveyed in the warp direction. An endless belt, a conveyance pulley that drives the endless belt, welding means for continuously welding predetermined portions of the hollow fibers of the knitted fabric, and closing an internal cavity thereof; and A welding thickness adjusting roller arranged above and below the hollow fiber knitted fabric and adjusting the thickness of a welded portion of the knitted fabric; a knitted fabric cooling means arranged downstream of the welded thickness adjusting roller; and the knitted fabric cooling means And a cutting means for cutting the knitted fabric at the welded portion, the cutting device being arranged downstream of the knitted fabric. 2. The cutting device according to claim 1, wherein the endless belt is disposed above and below the knitted fabric with the hollow fiber knitted fabric interposed therebetween. 3. The cutting device according to claim 1, wherein the welding unit, the welding thickness adjusting roller, and the knitted fabric cooling unit are arranged in a conveying path by the endless belt. 4. The cutting apparatus according to claim 3, wherein said welding means includes an ultrasonic welding machine and an anvil arranged to face each other via said endless belt. 5. The cutting device according to claim 3, wherein the welding unit includes a pair of heating devices arranged to face each other via the endless belt. 6. The cutting device according to claim 1, wherein said welding thickness adjusting roller has a plurality of thickness adjusting ridges at both ends.