JP2012121252A - Resin coating apparatus and resin coating method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress a use amount of resin applied to a resin-coated wire rod where a projection is formed at its outer periphery.SOLUTION: A resin coating apparatus 1 is provided with: a coating means 4 which continuously coats the whole periphery of a metal wire rod traveling from an upstream side to a downstream side with a molten resin along the longitudinal direction of the metal wire rod and; a projection forming means 7 which forms a plurality of intermittent resin projections 6 by intermittently coating a part of the periphery of the resin-coated metal wire rod where a coating layer of the resin is formed by the coating means 4 with the resin along the longitudinal direction; and a take-off means which takes off the metal wire rod in a traveling state that the metal wire rod travels or in a stopping state that the metal wire rod temporarily stops traveling in a freely switchable manner. When the take-off means is in the stopping state, the coating means 4 can supply the molten resin to the projection forming means. The projection forming means 7 has a metal mold where the molten resin is supplied from the coating means 4 when the take-off means is in the stopping state to form the resin projection and a metal mold opening/closing section by which the resin projection can be taken off out of the metal mold when the take-off means is in the traveling state.

Description

  The present invention relates to a resin coating apparatus and a resin coating method for coating a surface of a metal wire with a resin.

A technique for coating the surface of a metal wire material (bar material, wire material or pipe material) such as copper or steel with a thermoplastic resin such as PVC or PE is conventionally known. Such a metal wire is coated with a thermoplastic resin by a resin coating apparatus for the wire.
By the way, a wire coated with such a thermoplastic resin (hereinafter referred to as a resin-coated wire) has no outstanding feature in appearance after coating, and thus it is very difficult to distinguish by appearance. In particular, some AC power cables and signal cables are made by twisting together a plurality of resin-coated wires to form a single cable. With such cables, there is a desire to simplify the identification of resin-coated wires in wiring work. Is strong. For this reason, a technique has been developed in which such a resin-coated wire having no distinctive appearance is provided with a mark such as a protrusion to obtain a resin-coated wire having excellent discrimination.

  For example, Patent Literature 1 discloses a resin-coated wire material that has a “protrusion continuous in the longitudinal direction” formed on the surface of the resin-coated wire material to improve the discrimination of the resin-coated wire material. The technique of Patent Document 1 supplies a second resin different from the resin disposed on the surface of a metal wire, for example, a resin containing a colorant or the like in a molten state in a resin coating apparatus. In the apparatus of Patent Document 1, the second resin extruded from the auxiliary extruder is superposed on the first resin inside the crosshead body, and is extruded from the resin flow path while being superposed. The surface is covered.

JP 05-84611 A

  By the way, since the resin-coated wire in Patent Document 1 is formed with continuous protrusions, more resin is required than that without forming protrusions. With reference to the drawing of Patent Document 1, only a relatively small protrusion is shown. However, if the width of the protrusion is formed to be as wide as that of the metal wire or the height is further increased, A lot of resin is required. However, Patent Document 1 does not propose any means for suppressing the amount of resin used.

  This invention is made in view of the above-mentioned problem, and it aims at providing the resin coating apparatus and the resin coating method which can suppress the usage-amount of resin of the resin coating wire material in which protrusion was formed in the outer periphery. To do.

In order to solve the above problems, the resin coating apparatus of the present invention takes the following technical means.
That is, the resin coating apparatus according to the present invention is a coating means for continuously coating the molten resin along the longitudinal direction of the metal wire around the entire circumference of the metal wire traveling from the upstream side to the downstream side. And a protrusion forming means for forming a plurality of resin protrusions intermittently along the longitudinal direction with respect to a part of the periphery of the resin-coated wire having a resin coating layer formed by the covering means, and the metal wire. A take-up means that can be switched between a running state in which the take-up is carried out and a stop state in which the running of the metal wire is temporarily stopped, and the covering means is provided when the take-up means is in the stopped state. Molten resin can be supplied to the protrusion forming means, and the protrusion forming means is provided with a mold for forming the resin protrusion when the molten resin is supplied from the covering means when the take-up means is stopped. Have Moni, is characterized in that said take-up means comprise a mold closing unit which enables extraction to outside the mold the resin protrusion when a running state.

Preferably, the mold includes a recess for forming the resin protrusion, and a resin introduction gap for introducing the resin from the coating means into the recess is formed on the upstream side of the recess.
Further, the resin coating method of the present invention continuously coats the molten resin along the longitudinal direction of the metal wire material with respect to the entire circumference of the metal wire material traveling from the upstream side toward the downstream side, When forming a plurality of resin protrusions intermittently along the longitudinal direction by the protrusion forming means on a part of the periphery of the resin-coated wire having the resin coating layer formed thereon, the metal wire is continuously run. Switching between a running state to be stopped and a stopped state to temporarily stop the running of the metal wire, and when the metal wire is in a stopped state, the molten resin is supplied into the mold of the projection forming means. Then, the resin protrusion is formed, and when the metal wire is in a running state, the resin protrusion is taken out of the mold.

  Preferably, the mold is provided with a recess for forming the resin protrusion, and the resin introduction gap is formed on the upstream side of the recess, and the resin is introduced into the recess through the resin introduction gap. Good.

  According to the resin coating apparatus and the resin coating method of the present invention, it is possible to suppress the amount of resin used in the resin-coated wire having protrusions formed on the outer periphery.

It is front sectional drawing which shows the resin coating apparatus of this invention typically. It is the sectional view on the AA line of FIG. It is front sectional drawing of the resin coating apparatus in resin filling. It is a figure which shows the process of the resin coating method of this invention. It is a perspective view which shows typically the resin coating wire manufactured using the resin coating apparatus of this invention, (b) is the other example of the resin coating wire manufactured using the same resin coating apparatus typically It is a perspective view shown.

Hereinafter, embodiments of the resin coating apparatus 1 of the present invention will be described in detail with reference to the drawings.
FIG. 1 shows the overall configuration of a resin coating apparatus 1 of the present invention.
The resin coating apparatus 1 of the present invention includes a take-up machine (not shown) that can take up a coated wire that can run the metal wire W along its longitudinal direction, and a metal wire that runs by being taken up by the take-up machine. The entire periphery of W is provided with coating means 4 for coating with molten resin 3. Further, the resin coating apparatus 1 intermittently applies the resin 3 to the surface of the coating layer along the longitudinal direction with respect to a part of the periphery of the coated wire on which the coating layer of the resin 3 is formed by the coating means 4. In order to make it possible to cover (cover), a projection forming means 7 is provided for forming a plurality of resin projections 6 that are intermittent in the longitudinal direction of the coated wire on which the coating layer of the resin 3 is formed.

In the following description, the resin coating apparatus 1 performs coating while moving (running) the metal wire W horizontally from the left side to the right side in FIG. 1, and the left side in FIG. The upstream side when performing the operation and the right side of the sheet of FIG. 1 are the downstream side when describing the apparatus. Further, the upper and lower sides in FIG. 1 are the upper and lower sides when describing the apparatus.
The metal wire W which is the object to be coated with the resin 3 in the resin coating apparatus 1 is a long material (wire material, plate material, bar material or pipe material) formed of a metal such as copper or steel. Although the metal wire W of this embodiment is made of copper and has a rectangular cross-sectional shape, the cross-sectional shape of the metal wire W may be, for example, round (circular) or ring-shaped. Can be a solid bar or plate, or a hollow pipe.

A take-up machine (not shown) for moving the metal wire W along the horizontal direction is provided on the downstream side of the crosshead body 8 described later, and by taking up the coated wire after coating the metal wire W, It is to be sent horizontally toward the downstream side (right side in FIG. 1). The metal wire W thus moved by the take-up machine passes through the covering means 4.
The covering means 4 covers the periphery of the metal wire W with the molten resin 3. The covering means 4 includes a cored bar 10 that guides the metal wire W, a die 11 that covers the entire periphery of the metal wire W guided by the cored bar 10, and the cored bar 10 and the die 11. It has a crosshead body 8 (the main body of the covering means 4) housed inside.

  Specifically, the cored bar 10 is a member having a shape such that the funnel is laid down horizontally, a large-diameter cylindrical part 10a that opens to a large diameter, and a small-diameter cylindrical part that opens to a smaller diameter than the large-diameter cylindrical part 10a 10b, and a conical cylinder part 10c disposed between the large diameter cylinder part 10a and the small diameter cylinder part 10b. The cored bar 10 is arranged such that the large-diameter cylindrical portion 10a opened to the large diameter faces the upstream side and the small-diameter cylindrical portion 10b opened to the small diameter faces the downstream side.

  The crosshead body 8 is formed to be thick using a material such as a metal so as to withstand the pressure applied from the molten resin 3. Inside the cross head body 8, a cavity is formed in accordance with the outer shape of the cored bar 10 (the outer shape of the upstream side of the large-diameter cylindrical part 10a and the conical cylindrical part 10c). The tip of the small-diameter cylindrical portion 10b of the cored bar 10 protrudes from the cross head body 8 toward the downstream side.

  The cavity of the cross head body 8 is formed to have a size slightly larger than the outer shape of the core metal 10, and a gap is formed between the inner peripheral surface of the cross head body 8 and the outer peripheral surface of the core metal 10. A gap formed between the cross head body 8 and the cored bar 10 is a flow path through which the molten resin 3 can flow. An extruder (not shown) is provided on the upstream side of the flow path, and resin 3 plasticized by the extruder is supplied to the flow path.

On the other hand, the die 11 is disposed so as to be fitted into a portion on the downstream side of the cross head body 8. A cavity is also formed in the die 11 according to the outer shape of the cored bar 10 (the outer shape on the downstream side of the conical cylindrical part 10c and the small-diameter cylindrical part 10b), and the small-diameter cylindrical part 10b of the cored bar 10 is formed in this cavity. Is housed.
The cavity of the die 11 is also formed to be smaller than the cross head body 8, and a gap is formed between the inner peripheral surface of the die 11 and the outer peripheral surface of the cored bar 10. The gap formed between the die 11 and the core metal 10 is also a flow path through which the molten resin 3 can flow, and the resin 3 flowing through the flow path is pushed out from the downstream surface of the die 11. .

In the covering means 4 described above, the die 11 is covered with a portion protruding toward the downstream side of the core bar 10, the die 11 is covered with the cross head body 8 from the outside, and the opening of the cross head body 8 is opened. The die holding member 12 is fixed so as to be covered.
Thus, in the covering means 4, the resin 3 plasticized by the extruder is formed between the cross head body 8 and the cored bar 10, and then between the die 11 and the cored bar 10. It is extruded from the downstream end face of the die 11 through the gap. The resin 3 extruded in this manner is applied to the entire periphery of the metal wire W that has passed through the inside of the cored bar 10, and the metal wire W ( Hereinafter, the resin-coated wire will be manufactured.

By the way, about the resin-coated wire manufactured in this way, there is one in which a band-shaped protrusion (resin protrusion 6) is further formed on the resin 3 coating layer.
Therefore, in the resin coating apparatus 1 of the present invention, the periphery (surface) of the resin-coated wire on which the coating layer is formed by the above-described coating means 4 is further intermittently coated with the resin 3 along the longitudinal direction. 3 is further provided with a protrusion forming means 7 for forming a plurality of resin protrusions 6 formed in a protruding shape in the longitudinal direction.
Next, the protrusion forming means 7 will be described in detail.

As shown in FIGS. 1 and 2, the protrusion forming means 7 is a mold having a recess 13 for forming the resin protrusion 6 on the surface of the resin coating layer, and a closed state in which the mold covers the entire periphery of the coated wire. And a mold opening / closing portion 15 capable of repeatedly opening and closing the mold in an open state spaced from the peripheral surface.
The mold constituting the protrusion forming means 7 is composed of a moving mold and a fixed mold. In the present embodiment, a lower mold 17 is provided as a fixed mold, and an upper mold 16 is provided as a moving mold. The upper surface of the lower mold 17 is formed to match a part of the outer periphery of the resin-coated wire, and the resin-coated wire can be placed on the upper surface. In the illustrated example where the cross-sectional shape of the resin-coated wire is rectangular, the lower mold 17 is formed in a flat plate shape, and the upper surface thereof is formed in a flat surface. When the resin protrusion 6 is formed, the height position of the lower mold 17 is fixed in a state where the lower mold 17 is placed on a mold support base 18 that can be adjusted in the vertical direction.
As shown in FIG. 2, the upper mold 16 is a block-like member, and a groove portion 19 that opens downward is formed on the lower surface thereof. The groove portion 19 is formed on the lower surface of the upper mold 16 in accordance with the shape of the upper surface of the resin-coated wire so as to extend linearly from the upstream side toward the downstream side. Therefore, when the upper mold 16 is lowered and superimposed on the lower mold 17, the resin-coated wire material enters and is accommodated in the groove portion 19 of the upper mold 16.

  On the other hand, as shown in FIG. 1, a recess 13 is formed on the upper surface of the groove 19 of the upper mold 16 so as to be recessed further upward from the groove 19. The recess 13 has a shape corresponding to a resin protrusion 6 described later. In the case of the present embodiment, the recess 13 has a substantially rectangular parallelepiped shape (as shown in FIG. 5A). Can be formed.

In addition, when the upper mold 16 is lowered and stacked on the lower mold 17 between the upper mold 16 and the lower mold 17, the upper mold 16 and the lower mold 17 are resin-coated. Positioning pins 21 for positioning both molds in the horizontal direction are provided so as to match the cross-sectional shape of the wire.
Further, in the upper mold 16 and the lower mold 17, a cooling water flow path 24 through which cooling water flows is formed in order to quickly cool the extruded resin 3 and enable efficient formation of the resin protrusion 6. Has been.

  The mold opening / closing part 15 opens and closes the mold by moving the moving mold while guiding it. In the present embodiment, the mold opening / closing part 15 has a closed state in which the upper mold 16 is guided up and down and the concave portion 13 of the upper mold 16 is opposed to the coating layer, and an open state that is separated from the peripheral surface of the coating layer. It can be repeated alternately. The mold opening / closing part 15 is provided at four locations of the upper mold 16 (four positions surrounding the upper mold 16 in a balanced manner on a horizontal plane) and is a slide rail that guides the upper mold 16 along the vertical direction. 25 and a rack and pinion type lifting mechanism 26 that moves the upper mold 16 in the vertical direction relative to the lower mold 17.

The slide rail 25 is a rod-like member having an L-shaped cross section in a horizontal cross section, and is attached so as to be erected along the vertical direction, and restricts the movement of the upper mold 16 along the horizontal direction. However, the upper mold 16 can be guided up and down.
The elevating mechanism 26 includes a rack portion 27 linearly provided on the side surface of the upper mold 16 and a pinion gear 28 that meshes with the rack portion 27 and moves the upper mold 16 up and down. The upper mold 16 can be moved up and down relative to the lower mold 17 by rotating and driving the pinion gear 28 using an electric motor or the like, so that the mold composed of the upper mold 16 and the lower mold 17 can be opened and closed. It is like that.

  By the way, in order to form the resin protrusion 6 using the protrusion forming means 7 described above, for example, a through hole penetrating the inside of the upper mold 16 in the vertical direction is formed so that the lower end thereof opens into the recess 13. In this case, it is necessary to supply the molten resin 3 to the concave portion 13 of the mold in the closed state. However, when such a resin 3 supply means is employed, the structure of the mold is likely to be complicated, and an additional cost is required for processing the mold, and an extruder that supplies molten resin to the recess 13. This requires additional costs.

Therefore, in the resin coating apparatus 1 of the present invention, the resin 3 supplied from the coating means 4 is guided to the projection forming means 7 so that the projection can be formed only by the resin 3 supplied from the coating means 4. is there.
That is, the travel of the metal wire W is temporarily stopped, and the coating of the resin 3 on the metal wire W is temporarily stopped. During this travel stop, the covering means 4 can supply the resin 3 to be sent out by transferring the resin 3 to the protrusion forming means 7. Resin protrusions 6 are formed on the surface of the resin coating layer by the protrusion forming means 7 to which the resin 3 is supplied from the covering means 4.

  Specifically, the resin coating apparatus 1 of the present invention includes take-up means capable of switching between a running state in which the metal wire W is run by first taking it off and a stopped state in which the running of the metal wire W is temporarily stopped. ing. On the other hand, the covering means 4 can continuously send out the molten resin 3 even when the take-up means is in a stopped state, as in the case where the take-up means is in the running state. In the resin coating apparatus 1 of the present invention, the resin 3 fed out from the coating means 4 when the take-up means is in the stopped state is guided from the resin introduction gap 20 into the recess 13 of the mold, and the resin projection 6 Is forming.

Hereinafter, the characteristics of the take-up means and the covering means 4 provided in the resin coating apparatus 1 of the present invention will be described, and the resin introduction gap 20 will be described in detail.
Specifically, the take-up means described above includes a roller (not shown) that takes the metal wire W downstream of the covering means 4 in the conveyance direction of the metal wire W. The operation of the roller is controlled by, for example, an electric motor capable of adjusting the operation time and the stop time, and a traveling state in which the metal wire W continuously travels and a stop in which the travel of the metal wire W is temporarily stopped. The state can be selected alternately over a predetermined time.

On the other hand, the covering means 4 can continuously supply the molten resin 3 to the surface of the metal wire W. That is, whether the metal wire W is in the running state or in the stopped state, the covering means 4 continues to supply the molten resin 3 to the surface of the metal wire W from the end surface on the downstream side of the die 11.
Therefore, when the metal wire W is in a running state, the resin 3 is sequentially supplied to the entire periphery of the metal wire W taken from the take-up means, and the resin coating layer is continuously provided on the surface while continuously feeding the metal wire W. It becomes possible to form. Further, when the metal wire W is in a stopped state, most of the supplied resin 3 flows from the resin introduction gap 20 into the projection forming means 7 and is used for forming the resin projection 6 by the projection forming means 7.

As shown in FIG. 3, the resin introduction gap 20 is a gap necessary for smoothly guiding the molten resin 3 into the concave portion 13 of the mold forming the resin protrusion 6 from the coating means 4. Specifically, in the case of the protrusion forming means 7 of the present embodiment, the interval D shown in the enlarged view of FIG.
Specifically, a recess 13 that is recessed upward is formed at the center of the mold surface (lower surface) of the upper mold 16, and the mold surface surrounds the recess 13. It is arranged. A taper surface 22 that is inclined with respect to the horizontal direction is formed on the upstream mold surface of the mold surface surrounding the recess 13. The taper surface 22 is separated from the surface of the resin coating layer as it goes from the upstream side to the downstream side, and is in contact with the resin coating layer on the upstream side, but the distance from the resin coating layer is closer to the downstream side. Becomes larger. The distance between the downstream end of the taper surface 22 farthest from the resin coating layer and the resin coating layer, in other words, the maximum distance D between the taper surface 22 and the resin coating layer at the outlet of the die restraining member 12 is the above-described resin. An introduction gap 20 is obtained.

If the resin introduction gap 20 is provided in this way, the resin 3 supplied from the covering means 4 when the feeding of the metal wire W is stopped can be smoothly guided to the concave portion 13 of the mold. This is because the resin protrusion 6 can be easily formed on the surface of the coating layer.
In the case of this embodiment, the die holding member 12 is formed with a reverse taper surface 23 opposite to the taper surface 22.

  Specifically, the reverse tapered surface 23 is inclined so as to gradually approach the surface of the metal wire W toward the downstream side, and the resin 3 extruded from the rear end surface of the die 11 is along the inclined surface. Thus, the resin 3 can be brought into contact with the surface of the metal wire W. The metal wire W in contact with the molten resin 3 in this manner is pushed out together with the resin 3 from the opening (exit) on the rear end side of the die restraining member 12. That is, the opening on the rear end side of the die holding member 12 functions as a die of an extrusion nozzle that extrudes the resin-coated wire.

When the upper mold 16 is lowered by the pressing portion 15 and the mold is closed (closed state), the opening (exit) on the rear end side of the reverse taper surface 23 has a resin introduction gap. It is designed to communicate with the 20 entrances.
Next, a method of forming the resin protrusion 6 while performing resin coating using the above-described protrusion forming means 7, in other words, a resin coating method of the present embodiment will be described.

  As shown in FIGS. 3 and 4 (a) to 4 (e), the resin coating method of the present embodiment is melted over the entire circumference of the metal wire W traveling from the upstream side toward the downstream side. The resin 3 is continuously coated along the longitudinal direction of the metal wire W, and the resin 3 is intermittently provided along the longitudinal direction with respect to a part of the periphery of the resin-coated wire on which the coating layer of the resin 3 is formed. When covering, in other words, when forming a plurality of resin protrusions 6 that are intermittently formed by the protrusion forming means, a traveling state in which the metal wire W is continuously traveled, and a stop in which the travel of the metal wire W is temporarily stopped When the metal wire W is in a stopped state, the molten resin 3 is continuously supplied to the entire periphery of the metal wire W so that the resin 3 is formed in the mold. The resin projection 6 is shaped by introducing it into the mold through the resin introduction gap 20. It is intended to.

Specifically, resin coating is performed according to the following procedure.
As shown in FIG. 4 (a), the metal wire W is run along the horizontal direction, the molten resin 3 is extruded onto the surface of the running metal wire W, and the surface of the metal wire W is completely covered with the resin 3. Cover the periphery.
In this state, the resin-coated wire (metal wire W) is continuously running at a predetermined conveying speed (running speed), and the molten resin 3 is the reverse tapered surface 23 of the die restraining member 12 from the rear end face of the die 11. , And is extruded from the opening on the rear end face of the die restraining member 12 to cover the surface of the metal wire W.

As shown in FIG. 4B, in order to form the resin protrusion 6, the feeding of the metal wire W is temporarily stopped (in a stopped state). Then, in accordance with this temporary stop, the mold 17 that is the upper mold 16 is overlapped by using the mold opening / closing section 15 to close the mold.
Then, as shown in FIGS. 4C and 3, the resin 3 extruded from the opening of the rear end surface (upstream side surface) of the die restraining member 12 through the reverse tapered surface 23 enters the recess 13 of the mold. When entering, it is guided upward along the tapered surface 22 and flows into the recess 13 so as to get over the resin 3 already coated when entering the recess 13 of the mold. Therefore, the resin 3 can be smoothly guided to the concave portion 13 of the mold, and the resin protrusion 6 is easily formed on the surface of the resin coating layer.

As shown in FIG. 4D, when the concave portion 13 of the mold is filled with the resin 3, the resin protrusion 6 is reliably formed on the surface of the resin coating layer.
As shown in FIG. 4 (e), when the resin protrusion 6 is formed on the resin coating layer, the metal opening and closing part 15 is used to open the mold so that the resin protrusion 6 can be taken out, and then the metal wire rod Change W from the stopped state to the traveling state again. Thereafter, by repeating the operations shown in FIGS. 4A to 4E, a plurality of resin 3 protrusions can be intermittently formed in the longitudinal direction on the surface of the resin coating layer.

As shown in FIG. 5A, a plurality of resin protrusions 6 formed on the surface of the resin coating layer by the above-described resin coating method are provided intermittently in the longitudinal direction. If the resin protrusions 6 are intermittently formed in the longitudinal direction of the metal wire W in this way, the amount of the resin 3 necessary for forming the resin protrusions 6 can be suppressed as compared with that formed continuously.
Further, in the above resin coating method, the same resin 3 supplied from the same coating means 4 is used to form the resin coating layer and the resin protrusion 6, so that the resin for forming the resin protrusion 6 is used. There is no need to separately prepare a path for supplying the inside of the mold, and the apparatus configuration is simplified.

The above-described example is an example in which the resin protrusion 6 is formed on the surface of the rectangular metal wire W. However, as shown in FIG. 5B, the resin is applied to the surface of the metal wire W having a circular cross section. The protrusion 6 can also be formed.
As described above, by using the resin coating apparatus 1 of the present embodiment, the amount of the resin 3 necessary for forming the resin protrusions 6 can be suppressed to be smaller than that formed continuously.

  The present invention is not limited to the above embodiments, and the shape, structure, material, combination, cross-sectional shape of the metal wire, the shape of the resin protrusion, etc. can be appropriately changed without changing the essence of the invention. is there.

DESCRIPTION OF SYMBOLS 1 Resin coating apparatus 3 Resin 4 Coating | coated means 6 Resin protrusion 7 Protrusion formation means 8 Crosshead body 9 Sending roller 10 Core metal 10a Large diameter cylinder part of a core metal 10b Small diameter cylinder part of a core metal 10c Conical cylinder part of a core metal 11 Dice DESCRIPTION OF SYMBOLS 12 Die suppression member 13 Recess 15 Mold opening / closing part 16 Upper mold 17 Lower mold 18 Mold support base 19 Groove part 20 Resin introduction gap 21 Positioning pin 22 Tapered surface 23 Reverse taper surface 24 Cooling water flow path 25 Slide rail 26 Lifting mechanism 27 Rack part 28 Pinion gear W Metal wire

Claims (4)

Coating means for continuously covering the molten resin along the longitudinal direction of the metal wire with respect to the entire circumference of the metal wire traveling from the upstream side toward the downstream side,
Protrusion forming means for forming a plurality of resin protrusions intermittently along the longitudinal direction with respect to a part of the periphery of the resin-coated wire in which a resin coating layer is formed by the coating means;
Take-up means that can be switched between a running state in which the metal wire is run and a stop state in which the running of the metal wire is temporarily stopped, and
With
The covering means can supply molten resin to the protrusion forming means when the take-up means is in a stopped state,
The protrusion forming means has a mold for forming the resin protrusion by supplying molten resin from the covering means when the take-up means is in a stopped state, and the take-up means is in a running state. A resin coating apparatus comprising a mold opening / closing portion that enables the resin protrusion to be taken out of the mold.   The mold includes a recess for forming the resin protrusion, and a resin introduction gap for introducing the resin from the covering means into the recess is formed on the upstream side of the recess. The resin coating apparatus according to 1. A resin coating in which a molten resin is continuously coated along the longitudinal direction of the metal wire, and the resin coating layer is formed on the entire circumference of the metal wire traveling from the upstream side to the downstream side. When forming a plurality of resin protrusions intermittently along the longitudinal direction by the protrusion forming means on a part of the periphery of the wire,
The metal wire can be switched between a running state in which the metal wire is continuously run and a stopped state in which the running of the metal wire is temporarily stopped.
When the metal wire is in a stopped state, molten resin is supplied into the mold of the protrusion forming means to form the resin protrusion, and when the metal wire is in a running state, the resin protrusion is A resin coating method characterized by being taken out of the mold. Regarding the mold, a recess for forming the resin protrusion is provided, and a resin introduction gap is formed on the upstream side of the recess,
The resin coating method according to claim 3, wherein the resin is introduced into the concave portion through the resin introduction gap.