NL2004380A

NL2004380A - Welding-wire rewinding method.

Info

Publication number: NL2004380A
Application number: NL2004380A
Authority: NL
Inventors: Shinichi Nishimoto
Original assignee: Kobe Seiko Sho Kobe Steel Kk
Priority date: 2009-03-23
Filing date: 2010-03-11
Publication date: 2010-09-27
Also published as: CN101844709B; CN101844709A; KR20100106237A; KR101169858B1; NL2004380C2; JP2010222088A

Abstract

The invention provides a welding wire reeling method, after the welding wire from a bobbin is hung around a fixed side roller and a movable side roller of a tension adjusting roller device, the welding wire is reeled on a reel with the diameter smaller than that of the bobbin, wherein, an inlet side welding wire collector and an outlet side welding wire collector, capable of slidably clamping the moving welding wire are arranged near the inlet side and the outlet side of the welding wire of the tension adjusting roller device respectively, the tension of the welding wire at the inlet side and the outlet is controlled by the welding wire collectors.

Description

WELDING-WIRE REWINDING METHOD

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a welding-wirerewinding method of feeding a welding wire wound around abobbin and winding the welding wire around a spool having adiameter smaller than that of the bobbin.

2. Description of the Related Art

In a welding-wire rewinding apparatus that feeds awelding wire wound around a bobbin and winds the weldingwire around a spool having a diameter smaller than that ofthe bobbin, a dancer roller device is disposed between awire feeding unit having the bobbin set therein and a spoolwinding unit having set therein the spool around which thewelding wire fed from the bobbin is to be wound. Such adancer roller device has a function of maintaining thetension of the welding wire within a predetermined range byabsorbing fluctuations in the length of the welding wirecaused by stretching of the welding wire between the wirefeeding unit and the spool winding unit. Known examples ofa dancer roller device of the related art include aconfiguration disclosed in Japanese Unexamined Utility ModelRegistration Application Publication No. 58-060657.

First, a dancer roller device according to a first related-art example disclosed in the above publication willbe described with reference to Fig. 5, which is a side viewof this dancer roller device. A dancer roller device 51includes a fixed roller 55 provided at an upper section of aroller tower 54 and a movable roller 56 provided below thefixed roller 55. The movable roller 56 is configured to beslidably descendable to the lower side of the roller tower54 by the own weight of the movable roller 56. A weldingwire 52 is hooked around the fixed roller 55 and the movableroller 56, is subsequently delivered in the direction of anarrow in the drawing, and is then wound around a wire drum(not shown), a spool (not shown), or the like via adjustmentrollers 58 and a casting roller 59.

Reference numeral 53 in the drawing denotes a wirereceiving unit, 54a denotes a sliding rod, and 56a denotes ahollow sliding member slidably fitted around the sliding rod54a.

Next, a dancer roller device according to a secondrelated-art example disclosed in the same publication willbe described with reference to Fig. 6A, which is a schematicview thereof, and Fig. 6B, which is a side view thereof.Reference numeral 61 in the drawings denote a dancer rollerdevice. In the dancer roller device 61, a movable roller ischanged from a sliding type, as in the first related-artexample, to a rocking type. Specifically, a fixed roller 65 is supported by a roller-supporting bracket having atriangular shape in side view and formed on the right sideof a dancer frame 61a in Fig. 6B. A movable roller 66located below the fixed roller 65 is provided at one end ofan arm 70 pivotally supported by a hinge 74 provided near aleft corner of the dancer frame 61a in the drawing. Arocking shock-absorbing mechanism 67, to be described below,is provided at the other end of the arm 70.

The rocking shock-absorbing mechanism 67 includes abalance weight 71 provided at the other end of the arm 70and an air cylinder 72 whose bottom is fixed to anappropriate section of the dancer frame 61a and which causesthe arm 70 and the movable roller 66 to move downwardagainst the balance weight 71. One end of a wire 75 isfastened to an end of a rod of the balance weight 71, andthe other end of the wire 75 is wound around a pulley 73that rotates coaxially with the hinge 74. The rockingshock-absorbing mechanism 67 has a function of suppressingthe movable roller 66, which tries to descend in thedirection of its own weight G, with a first rotation momentW produced by the gravity of the balance weight 71, and alsohas an adjusting function of elastically complementing thesuppressed self-weight descending force by producing asecond rotation moment V acting in a direction against thisfirst rotation moment W by using a pulling force by the air cylinder 72 so as to allow the movable roller 66 to movesmoothly. A welding wire 62 received by a wire receivingunit 63 is hooked around the fixed roller 65 and the movableroller 66, is subsequently delivered in the direction of anarrow in the drawing, and is then wound around a wire drum,a spool, or the like via adjustment rollers 68 and a castingroller (not shown).

Unlike the movable roller in the dancer roller deviceaccording to the first related-art example, the movableroller in the dancer roller device according to the secondrelated-art example is not restrained by a sliding rod orthe like, and the movable roller 66 thus tries to descendquickly due to its own weight. However, since the rockingshock-absorbing mechanism 67 prevents a rapid descent of themovable roller 66, excessive tension is prevented from beingapplied to the welding wire.

With the dancer roller device according to the firstand second related-art examples, the rates of drivingsources before and after the dancer roller device aresynchronously controlled. Moreover, the dancer rollerdevice is extremely advantageous in that it maintains thetension of the welding wire within a predetermined range byabsorbing fluctuations in the length of the welding wire dueto stretching thereof by causing the movable roller to movetoward and away from the fixed roller. However, even in the dancer roller device according to the first and secondrelated-art examples, the welding wire may undulate due to acertain reason during the welding-wire rewinding process.Since the tension of the welding wire is unstable whenundulating, the quality of the welding wire is loweredduring this period of undulation, which is a problem thatshould be solved. It is needless to say that an undulationphenomenon of the welding wire can be eliminated by stoppingthe operation of the welding-wire rewinding apparatus.However, eliminating the undulation phenomenon of thewelding wire while continuing the operation of the welding-wire rewinding apparatus is preferred for preventing theproductivity from being lowered.

There may also be a case where the welding wire is cutwhen excessive tension is applied to the welding wire due toa certain reason during the welding-wire rewinding process.Since the tension is lost when the welding wire is cut, thewelding wire becomes detached from a roller in the wirereceiving unit 63, the fixed roller, the movable roller, theadjustment rollers, and the like. As a result, when thewelding-wire rewinding process is to be resumed, the weldingwire needs to be hooked around the roller in the wirereceiving unit 63, the fixed roller, and the movable rollerand also needs to be extended through between the adjustmentrollers. Therefore, in order to resume the welding-wire rewinding process, an enormous amount of labor for settingthe welding wire is required in addition to a long period oftime (resulting in lower productivity due to a reducedoperation rate), which is a problem that should be solved.

SUMMARY OF THE INVENTION

Accordingly, it is an object of the present inventionto provide a welding-wire rewinding method that allows foran adjustment of the tension of a welding wire byeliminating an undulation phenomenon occurring during arewinding process and that also allows a welding-wiresetting process to be completed with a small amount of laborand within a short period of time even when the welding wireis cut.

In order to solve the aforementioned problems, thepresent invention provides a welding-wire rewinding methodof winding a welding wire fed from a bobbin around a spoolhaving a diameter smaller than that of the bobbin in a statewhere the welding wire is hooked around a fixed roller and amovable roller of a dancer roller device, the method beingperformed while controlling the tension at an entrance sideand an exit side of the welding wire in the dancer rollerdevice and synchronously controlling the rates of drivingsources before and after the dancer roller device. In thewelding-wire rewinding method, wire catchers that nip the welding wire while permitting sliding of the welding wireare respectively provided near both the entrance side andthe exit side of the welding wire in the dancer rollerdevice.

In the welding-wire rewinding method according to thepresent invention, an undulation phenomenon occurring in thewelding wire driven by actuating the driving sources can beeliminated by nipping the welding wire in a slidable mannerby actuating the wire catchers provided near both theentrance side and the exit side of the welding wire in thedancer roller device, whereby the tension of the weldingwire can be stably controlled. Therefore, with the welding-wire rewinding method according to the present invention,since a decrease in the tension of the welding wire causedby an undulation phenomenon can be prevented, the quality ofthe welding wire wound around the spool during the welding-wire rewinding process is prevented from being lowered. Itis needless to say that the productivity is not loweredsince the welding-wire rewinding process is not stopped.

Furthermore, in the welding-wire rewinding methodaccording to the present invention, even when the operationof a welding-wire rewinding apparatus is stopped uponcompletion of the welding-wire rewinding process, becausethe welding wire is nipped by the wire catchers, the tensionbetween near the entrance side and the exit side of the welding wire, which is wound around the fixed roller and themovable roller of the dancer roller device, can be properlymaintained. Therefore, in the welding-wire rewinding methodaccording to the present invention, since it is notnecessary to adjust the tension of the welding wire whencommencing a process of winding the welding wire around anew winding drum or spool, the winding process of thewelding wire can be commenced within a short period of time,thereby contributing to enhanced rewinding efficiency of thewelding wire.

In the welding-wire rewinding method described above,the wire catchers may each include a pressing body that nipsthe welding wire.

With such a welding-wire rewinding method, anundulation phenomenon of the welding wire is eliminated bythe nipping by the pressing bodies of the wire catchers,whereby the tension is maintained.

In the welding-wire rewinding method, feeding andwinding of the welding wire may be stopped in response to asignal output from a wire-cut detection sensor that detectsthat the welding wire is cut, and the wire catchers may beactuated so as to nip the welding wire.

With such a welding-wire rewinding method, when thefeeding and the winding of the welding wire are stopped inresponse to a signal output from the wire-cut detection sensor that detects that the welding wire is cut, the wirecatchers nip the welding wire near both the entrance sideand the exit side thereof in the dancer roller device.Therefore, since the welding wire hooked around the fixedroller and the movable roller receives certain tension, thewelding wire hooked around the fixed roller and the movableroller is prevented from sagging or from being detached fromthe fixed roller and the movable roller.

The wire catchers may each include a pressing body thatnips the welding wire and pressing-body actuating meansconfigured to actuate the pressing body, and the wire-cutdetection sensor may include an electric bar that actuatesthe pressing-body actuating means by receiving electricityon the basis of contact with the cut welding wire.

Accordingly, both sections of the welding wire near theentrance side and the exit side thereof in the dancer rollerdevice are nipped by the pressing bodies of the wirecatchers that are actuated by actuation of the pressing-bodyactuating means by the electric bar that receiveselectricity on the basis of contact with the cut weldingwire.

Alternatively, the wire-cut detection sensor mayinclude a stopper at an upper end thereof, a slidably-descendable sliding rod having a roller, which is rotatablyin contact with the welding wire, at a lower end thereof, a rod-supporting member slidably supporting the sliding rodand having a stopper contact surface, and a limit switchthat detects a descent of the sliding rod, which descendswhen the welding wire is cut, and actuates pressing-bodyactuating means configured to actuate the pressing body.

Accordingly, both sections of the welding wire near theentrance side and the exit side thereof in the dancer rollerdevice are nipped by the pressing bodies of the wirecatchers that are actuated by actuation of the pressing-bodyactuating means by the limit switch that detects a descentof the sliding rod, which descends when the welding wire iscut.

As a further alternative, the wire-cut detection sensormay include a rotating rod whose intermediate sectionbetween one end and another end thereof is rotatablysupported by a rotatably-supporting section and having aroller, which is rotatably in contact with the welding wire,at the one end thereof, and a limit switch that comes intocontact with the other end of the rotating rod, whichrotates when the welding wire is cut, and actuates pressing-body actuating means configured to actuate the pressing body.

Accordingly, both sections of the welding wire near theentrance side and the exit side thereof in the dancer rollerdevice are nipped by the pressing bodies of the wirecatchers that are actuated by actuation of the pressing-body actuating means by the limit switch that comes into contactwith the other end of the rotating rod, which rotates whenthe welding wire is cut.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a schematic side view of a welding-wirerewinding apparatus according to an embodiment of thepresent invention;

Fig. 2 is a schematic cross-sectional view of a wirecatcher according to an embodiment of the present invention;

Fig. 3Ά is a schematic side view for explaining theconfiguration of a wire-cut detection sensor according to anembodiment of the present invention that detects that awelding wire is cut, and Fig. 3B is a schematic plan viewfor explaining the configuration of the wire-cut detectionsensor that detects that a welding wire is cut;

Fig. 4A is a schematic view for explaining theconfiguration of a wire-cut detection sensor according toanother embodiment that detects that a welding wire is cut,and Fig. 4B is a schematic view for explaining theconfiguration of a wire-cut detection sensor according toyet another embodiment that detects that a welding wire iscut;

Fig. 5 is a side view of a dancer roller deviceaccording to a first related-art example; and

Fig. 6A is a schematic view of a dancer roller deviceaccording to a second related-art example, and Fig. 6B is aside view of the dancer roller device.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

A welding-wire rewinding apparatus according to anembodiment for implementing a welding-wire rewinding methodaccording to the present invention will be described belowwith reference to the attached drawings. Fig. 1 is aschematic side view of the welding-wire rewinding apparatusaccording to the embodiment of the present invention. Fig.

2 is a schematic cross-sectional view of a wire catcher.

Fig. 3A is a schematic side view for explaining theconfiguration of a wire-cut detection sensor that detectsthat a welding wire is cut. Fig. 3B is a schematic planview for explaining the configuration of the wire-cutdetection sensor that detects that a welding wire is cut.Specifically, Fig. 3B is a diagram as viewed from an arrow Ain Fig. 3A. Fig. 4A is a schematic view for explaining theconfiguration of a wire-cut detection sensor according toanother embodiment that detects that a welding wire is cut.Fig. 4B is a schematic view for explaining the configurationof a wire-cut detection sensor according to yet anotherembodiment that detects that a welding wire is cut.

Reference numeral 1 shown in Fig. 1 denotes a welding- wire rewinding apparatus that winds a welding wire (flux-cored and having a diameter of 1.2 to 1.6 mm) wound around abobbin onto a spool or the like having a diameter smallerthan that of the bobbin. This welding-wire rewindingapparatus 1 includes a wire feeding unit 2 in which a bobbin3 is set and a wire receiving unit 4 that receives a weldingwire 5 fed from the bobbin 3. A dancer roller device 11, tobe described below, is disposed between the wire receivingunit 4 and a spool winding unit 6 that has a detachablespool 7 set therein and that winds the welding wire 5therearound. This dancer roller device 11 has a function ofmaintaining the tension of the welding wire 5 within apredetermined range by absorbing fluctuations in the lengthof the welding wire 5 between the wire receiving unit 4 andthe spool winding unit 6, and is configured as describedbelow. Driving sources for the wire feeding unit 2, thewire receiving unit 4, the spool winding unit 6, and thelike are synchronously controlled by a control board (notshown).

Specifically, in the dancer roller device 11, a fixedroller 12 is supported by a roller-supporting bracket havinga triangular shape in side view and formed on the right sideof a dancer frame 11a in Fig. 1. A movable roller 13located below the fixed roller 12 is provided at one end ofan arm 15 pivotally supported by a hinge 19 provided near a left corner of the dancer frame 11a in Fig. 1. A rockingshock-absorbing mechanism 14, to be described below, isprovided at the other end of the arm 15.

The rocking shock-absorbing mechanism 14 includes abalance weight 16 provided at the other end of the arm 15and an air cylinder 17 whose bottom is fixed to anappropriate section of the dancer frame 11a and which causesthe arm 15 and the movable roller 13 to move downwardagainst the balance weight 16. One end of a wire 20 isfastened to an end of a rod of the balance weight 16, andthe other end of the wire 20 is wound around a pulley 18that rotates coaxially with the hinge 19.

The rocking shock-absorbing mechanism 14 has a functionof suppressing the movable roller 13, which tries to descendin the direction of its own weight G, with a first rotationmoment W produced by the gravity of the balance weight 16,and also has an adjusting function of elasticallycomplementing the suppressed self-weight descending force byproducing a second rotation moment V acting in a directionagainst this first rotation moment W by using a pullingforce by the air cylinder 17 so as to allow the movableroller 13 to move smoothly. The welding wire 5 received bythe wire receiving unit 4 is rewound by being hooked aroundthe fixed roller 12 and the movable roller 13, then beingdelivered in the direction of an arrow in the drawing, and finally being wound around the spool 7 set in the spoolwinding unit 6 via adjustment rollers (not shown) and acasting roller 8.

As it is clearly understood from the above descriptionregarding the configuration of the dancer roller device 11in the welding-wire rewinding apparatus 1, the aboveconfiguration of the dancer roller device 11 issubstantially the same as that of the dancer roller device61 according to the aforementioned second related-artexample. In the case of the dancer roller device 11 in thewelding-wire rewinding apparatus 1 according to theembodiment of the present invention, an entrance-side wirecatcher 21 is provided near the entrance side of the weldingwire 5 in the dancer roller device 11, and an exit-side wirecatcher 22 is provided near the exit side of the weldingwire 5.

When an undulation phenomenon that causes the tensionof the running welding wire 5 to fluctuate occurs, theentrance-side wire catcher 21 and the exit-side wire catcher22 are actuated to nip the welding wire 5 in a slidablemanner, thereby eliminating the undulation phenomenon (thenipping force applied to the welding wire 5 is releasedafter the elimination of the undulation phenomenon).Consequently, the tension between the entrance side and theexit side of the welding wire 5 in the dancer roller device 11 during a welding-wire rewinding process is controlled.

Furthermore, when the operation of the welding-wirerewinding apparatus 1 is stopped at the time when thewelding wire 5 is cut upon completion of the rewindingprocess of the welding wire 5, the welding wire 5 stoppedfrom running can be nipped at the stopped position.

Next, the configuration of the entrance-side wirecatcher 21 and the exit-side wire catcher 22 will bedescribed with reference to Fig. 2, which is an attached drawing. Since the entrance-side wire catcher 21 and theexit-side wire catcher 22 have completely the sameconfiguration, the following description of theconfiguration thereof will be directed to the entrance-sidewire catcher 21 as an example. Specifically, as shown inFig. 2, the entrance-side wire catcher 21 according to thisembodiment includes a plate 21a and a casing 21d, to bedescribed below, facing the plate 21a at a positionseparated therefrom by a predetermined distance. Upper endsof the plate 21a and the casing 21d in the drawing areintegrally connected to each other with a connecting member21c.

A fixed pressing body 21b is fixed to a side of theplate 21a opposite the casing 21d, and a piston 21f having arod-shaped movable pressing body 21g is accommodated in apiston chamber 21e covered with a sealing cover 21i of the casing 2ld. The piston chamber 21e is provided with anelectromagnetic valve (corresponding to pressing-bodyactuating means) (not shown) via which the piston chamber21e is in communication with the atmosphere. When thewelding-wire rewinding process is properly performed, themovable pressing body 21g is kept distant from the fixedpressing body 21b by a return spring (pressing-bodyactuating means) 21h. On the other hand, when an undulationphenomenon occurs in the running welding wire 5, when thewelding-wire rewinding process is completed, or when theoperation of the welding-wire rewinding apparatus 1 isstopped at the time when the welding wire is cut, airpressure with a predetermined pressure value is supplied tothe piston chamber 21e from a compressed-air supply source(not shown) by switching the electromagnetic valve, so as tocause the movable pressing body 21g to move towards thefixed pressing body 21b.

When the winding process of the welding wire 5 woundaround the bobbin 3 set in the wire feeding unit 2 iscompleted and a subsequent welding-wire rewinding process ofsetting a new bobbin 3 and guiding a welding wire 5 pulledout from the new bobbin 3 to the spool 7 set in the spoolwinding unit 6 via the wire receiving unit 4 and the dancerroller device 11 is to be performed, the electromagneticvalve is switched and the return spring 21h causes the movable pressing body 21g to move away from the fixedpressing body 21b. Unless there is an anomaly (such as anundulation phenomenon or a cut wire) in the winding processof the welding wire 5, the aforementioned state where themovable pressing body 21g is kept distant from the fixedpressing body 21b is continuously maintained throughout thecourse of the winding process. Although the piston chamber21e is provided only on one side of each of the entrance-side wire catcher 21 and the exit-side wire catcher 22 inthis embodiment of the present invention, an alternativeconfiguration in which piston chambers 21e are provided onopposite sides of the welding wire 5 is also permissible.Furthermore, although the entrance-side wire catcher 21 andthe exit-side wire catcher 22 are each configured to nip therunning welding wire 5 from the left and right sides, analternative configuration in which the welding wire 5 isnipped from above and below is also permissible. Moreover,the wire catchers are not limited to the aboveconfigurations so long as they are capable of nipping arunning welding wire.

In the case of the welding-wire rewinding apparatus 1according to the embodiment of the present invention, if thewelding wire 5 is cut by the occurrence of excessive tensiondue to a certain reason, the operation of the welding-wirerewinding apparatus 1 is stopped in response to a signal output from a wire-cut detection sensor 23, to be describedbelow, that detects that the welding wire 5 is cut, wherebythe feeding and the winding of the welding wire 5 arestopped. It is needless to say that, even when theoperation of the welding-wire rewinding apparatus 1 isstopped, air pressure with a predetermined pressure value issupplied to the piston chambers 21e in the entrance-side andexit-side wire catchers 21 and 22 via the electromagneticvalves, as described above.

As shown in Figs. 3A and 3B, the wire-cut detectionsensor 23 includes an electric bar 23a bridged laterally ina direction orthogonal to the feeding direction of thewelding wire 5 and disposed above the welding wire 5 fedfrom the bobbin 3 set in the wire feeding unit 2. Theelectric bar 23a receives electric current when the cutwelding wire 5 swung around by the bobbin 3 comes intocontact therewith, and sends the electric current as awelding-wire cut signal, via a lead wire 23b, to the controlboard (not shown), which synchronously controls the drivingsources of the welding-wire rewinding apparatus 1. Theelectric bar 23a may be disposed at any position where a cutwelding wire can come into contact therewith. Although theelectric bar 23a is preferably bridged laterally in adirection orthogonal to the wire feeding direction anddisposed above the welding wire, as mentioned above, the disposition thereof is not limited.

As described above, the wire-cut detection sensor 23 inthe welding-wire rewinding apparatus 1 according to theabove embodiment includes the electric bar 23a. However,the wire-cut detection sensor is not limited to the typehaving such a configuration and may alternatively be, forexample, a wire-cut detection sensor having one of theconfigurations shown in Figs. 4A and 4B.

Specifically, a wire-cut detection sensor 24 shown inFig. 4A includes a stopper 24b at an upper end thereof, andalso includes a slidably-descendable sliding rod 24a havinga roller 24c, which is rotatably in contact with the weldingwire 5, at a lower end thereof. The sliding rod 24a issupported in a vertically slidable manner by a rod¬supporting member 24d having a stopper contact surface 24ewith which a lower surface of the stopper 24b is in contact.Furthermore, there is also provided a limit switch 24f thatdetects that the welding wire 5 is cut in accordance with adescent of the sliding rod 24a, which descends when thewelding wire 5 is cut, and sends the detected cut signal tothe control board (not shown) that controls the operation ofthe welding-wire rewinding apparatus 1, so as to stop theoperation of the welding-wire rewinding apparatus 1.

A wire-cut detection sensor 25 shown in Fig. 4Bincludes a rotating rod 25a whose intermediate section between one end and the other end thereof is rotatablysupported by a rotatably-supporting section 25c and having aroller 25b, which is rotatably in contact with the weldingwire 5, at the one end thereof. Furthermore, there is alsoprovided a limit switch 25d that detects that the weldingwire 5 is cut by coming into contact with the other end ofthe rotating rod 25a, which rotates when the welding wire 5is cut, and sends the detected cut signal to the controlboard (not shown) that controls the operation of thewelding-wire rewinding apparatus 1, so as to stop theoperation of the welding-wire rewinding apparatus 1.Reference numeral 25e denotes a stopper that regulates thelowermost rotational position of the rotating rod 25a.

The operation of the welding-wire rewinding apparatus 1having the above configuration for implementing the welding-wire rewinding method according to the present inventionwill be described below. Specifically, when the operationof the welding-wire rewinding apparatus 1 is commenced byoperating the control board (not shown), the welding wire 5fed from the bobbin 3 by the wire feeding unit 2 is receivedby the wire receiving unit 4. The welding wire 5 exitingthe wire receiving unit 4 travels through the entrance-sidewire catcher 21, the fixed roller 12 and the movable roller13 of the dancer roller device 11, then through the fixedroller 12, the exit-side wire catcher 22, and the casting roller 8 so as to be rewound by being wound around the spool7 set in the spool winding unit 6.

When the winding process of the welding wire 5 by thespool 7 is completed by a continuous operation of thewelding-wire rewinding apparatus 1, the operation of thewelding-wire rewinding apparatus 1 is stopped and theentrance-side wire catcher 21 and the exit-side wire catcher22 nip the welding wire 5 near the entrance side and theexit side thereof in the dancer roller device 11. Then, aprocess of setting a new spool 7 in the spool winding unit 6and winding the welding wire 5 around the newly set spool 7is commenced, and this process is repeatedly performed. Itis needless to say that when the welding wire 5 wound aroundthe bobbin 3 is entirely rewound around the spool 7, theoperation of the welding-wire rewinding apparatus 1 isstopped.

Then, after performing a welding-wire setting processof setting a new bobbin 3, around which a welding wire iswound, in the wire feeding unit 2 and guiding the weldingwire 5 pulled out from the new bobbin 3 to the spool 7 setin the spool winding unit 6 via the wire receiving unit 4and the dancer roller device 11, the operation of thewelding-wire rewinding apparatus 1 is commenced.

When an undulation phenomenon occurs in the runningwelding wire 5 during the above-described rewinding process of the welding wire 5 in the welding-wire rewindingapparatus 1, the entrance-side wire catcher 21 provided nearthe entrance side of the welding wire 5 in the dancer rollerdevice 11 and the exit-side wire catcher 22 provided nearthe exit side are actuated so as to nip the welding wire 5in a slidable manner, thereby eliminating the undulationphenomenon in the welding wire 5 (the nipping force appliedto the welding wire 5 is released after the elimination ofthe undulation phenomenon) and controlling the tensionthereof. Consequently, a decrease in the tension of thewelding wire 5 caused by an undulation phenomenon isprevented, thereby preventing the product quality of thewelding wire 5 wound around the spool 7 from being lowered.In this case, since the undulation phenomenon can beeliminated while continuing the welding-wire rewindingprocess, the productivity is not lowered.

Furthermore, even when the operation of the welding-wire rewinding apparatus 1 is stopped upon completion of thewelding-wire rewinding process, because the welding wire 5is nipped by the entrance-side wire catcher 21 and the exit-side wire catcher 22, the tension between near the entranceside and the exit side of the welding wire 5, which ishooked around the fixed roller 12 and the movable roller 13of the dancer roller device 11, can be properly maintained.Accordingly, since it is not necessary to adjust the tension of the welding wire 5 when commencing a process of windingthe welding wire 5 around a new spool 7, the winding processof the welding wire 5 can be commenced within a short periodof time, thereby significantly contributing to enhancedrewinding efficiency of the welding wire 5.

Furthermore, even when the feeding and the winding ofthe welding wire 5 are stopped upon stoppage of theoperation of the welding-wire rewinding apparatus 1 inresponse to a signal output from the wire-cut detectionsensor 23 that detects that the welding wire 5 is cut, theentrance-side wire catcher 21 and the exit-side wire catcher22 nip near the entrance side and the exit side of thewelding wire 5 hooked around the fixed roller 12 and themovable roller 13 of the dancer roller device 11.

With the nipping of the welding wire 5 near theentrance side and the exit side thereof, the welding wire 5hooked around the fixed roller 12 and the movable roller 13receives certain tension so that the welding wire 5 hookedaround the fixed roller 12 and the movable roller 13 isprevented from sagging or from being detached from the fixedroller 12 and the movable roller 13. This eliminates theneed for hooking the welding wire 5 around the fixed roller12 and the movable roller 13 after restoring a cut weldingwire 5 and thus allows the winding process of the weldingwire 5 to be commenced within a short period of time, thereby significantly contributing to enhanced rewindingefficiency of the welding wire 5. The nipping force appliedto the welding wire 5 by the entrance-side and exit-sidewire catchers 21 and 22 when the operation of the welding-wire rewinding apparatus 1 is stopped at the time when thewelding wire 5 is cut or when the welding-wire rewindingprocess is completed may be greater than or equal to anipping force that permits sliding of the welding wire 5when eliminating an undulation phenomenon in the runningwelding wire 5. The welding wire 5 may be incapable ofsliding at such a time of stoppage of the operation.

The welding-wire rewinding method according to theabove embodiment of the present invention is described asbeing applied to the dancer roller device with theconfiguration according to the aforementioned secondrelated-art example as an example. However, since thepresent invention is not limited to such a configuration andmay also be applied to, for example, the dancer rollerdevice according to the aforementioned first related-artexample, the invention is not limited to the configurationaccording to the above embodiment and is freely modifiablewithin the scope not deviating from the technical idea ofthe invention. Furthermore, although the above descriptionis directed to a mode for rewinding a flux-cored weldingwire, the invention can be applied to a mode for rewinding other welding wires, such as a solid welding wire.

As described above, according to the present invention,a welding wire wound around a bobbin can efficiently bewound around a spool having a' diameter smaller than that ofthe bobbin. Therefore, the invention is suitable for anapparatus and a method for rewinding a welding wiremanufactured in a highly efficient production line, such asa flux-cored welding wire manufactured by continuouslyperforming a step of molding a coil-like hoop (steel strip)into a U-shaped steep strip by rewinding the hoop, a step offilling the hoop with the flux in the course of the moldingstep, and a step of winding the tubular-molded wire filledwith the flux while further extending the wire in the sameline.

Claims

A method for rewinding a welding wire, wherein a welding wire supplied from a reel is wound onto a spool having a smaller diameter than that of the reel, in a state in which the welding wire is around a fixed roll and a movable roll of a roll-rolling device hooked, the method being carried out while the voltage on an input side and an output side of the welding wire in the dance roller device is controlled and simultaneously the speeds of drive sources before and after the dance roller device are controlled, wherein wire catchers clamping the welding wire while allowing the welding wire to slide in the vicinity of both the input side and the output side of the welding wire in the dance roll device.

The method for rewinding a welding wire according to Claim 1, wherein the wire catchers each comprise a pressure body that clamps the welding wire.

The method for rewinding a welding wire according to any of Claims 1 and 2, wherein feeding and winding the welding wire in response to a signal delivered by a wire break detection sensor that detects that the welding wire is broken are stopped, and the wire catchers are activated so that they the welding wire clips.

The method for rewinding a welding wire according to Claim 3, the wire catchers each comprising a pressure body clamping the welding wire and a means for activating the pressure body oriented to activate the pressure body, and the wire break detection sensor comprising an electric rod that activates the means for activating of the pressure body activates by electricity received on the basis of contact with the broken welding wire.

The method for rewinding a welding wire according to Claim 3, the wire break detection sensor comprising a stopper on a top thereof, a sliding rod, which can slide down, with a roller rotatably in contact with the welding wire, on a bottom thereof, a member for supporting a rod which supports the sliding rod sliding and which has a stopper contact surface, and a limiter switch which detects a fall of the sliding rod, drops when the welding wire is broken, and wherein the sensor activates a means for activating a pressure body, which is arranged to activate the pressure body.

The method for rewinding a welding wire according to Claim 3, wherein the wire break detection sensor comprises a rotating rod, the central portion of which is supported between one end and another end by a rotatable support section and includes a roll rotatably in contact with the welding wire, at the end thereof, and a limiter switch that contacts the other end of the rotating rod, which rotates when the welding wire is broken, and activates a means for activating a pressure body adapted to activate the pressure body.