JP2018027647A - Die plate and method for manufacturing bead wire having rubber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technology for manufacturing a bead wire having rubber, capable of manufacturing the bead wire at a high speed without generating the peeling of rubber even when increasing a speed at which the bead wire passes through a die plate.SOLUTION: A conical extrusion hole tapering toward a surface on the downstream side from a surface on the upstream side in the supply direction of a bead wire penetrates is formed to penetrate. The die plate coats rubber on the bead wire by passing the bead wire supplied from a baffle together with rubber through a the extrusion hole, and the wall surface of the extrusion hole is subjected to uneven processing for rotating the rubber supplied to the extrusion hole around the bead wire.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a die plate used for manufacturing a bead wire with rubber and a method for manufacturing a bead wire with rubber using the die plate.

  The bead core of the pneumatic tire is manufactured by winding a bead wire in an annular shape. In the production of this bead core, conventionally, a bead wire with rubber in which the outer peripheral surface of the bead wire is coated with rubber has been used in order to increase the adhesion between the bead wires (Patent Documents 1 and 2).

  In order to manufacture such a bead wire with rubber, an extrusion molding machine including a baffle having an alignment groove for aligning the bead wires and a die plate attached to the tip of the baffle is used.

  FIG. 5 is a perspective view showing a conventional die plate, as viewed from the upstream side in the supply direction of the bead wire. As shown in FIG. 5, the die plate 50 is provided with a conical extrusion hole 51 that tapers from the upstream surface to the downstream surface in the supply direction of the bead wire so as to penetrate the die plate. By passing the bead wire and the rubber supplied from the baffle (not shown) through the extrusion hole 51, the rubber adheres around the bead wire, and the bead wire with rubber is manufactured.

JP 2003-340926 A JP 2009-73029 A

  In the production of the above-described bead wire with rubber, in recent years, it is required to increase the production rate of the bead wire in order to improve the production efficiency.

  However, if the speed at which the bead wire is passed through the extrusion hole 51 is too high, as shown in FIG. 6, the rubber G hardly adheres to the bead wire, and the bead wire W1 with rubber with the rubber peeling B produced is produced. Will be.

  In particular, when a bead wire W having a twisted wire structure in which a plurality of single wire W2 as shown in FIG. 7 is twisted and gathered as a bead wire is used, the rubber should be sufficiently distributed in the gap between each single wire W. It becomes difficult to peel off the rubber described above.

  Therefore, the present invention provides a rubber bead wire manufacturing technique that does not cause rubber peeling even when the speed at which the bead wire passes through the die plate is increased, and enables the bead wire to be manufactured at a high speed. The issue is to provide.

The invention described in claim 1
A conical extrusion hole tapering from the upstream surface to the downstream surface in the supply direction of the bead wire is formed so as to penetrate the bead wire supplied from the baffle together with the rubber into the extrusion hole. A die plate that coats the bead wire with the rubber by passing it through;
The die plate is characterized in that unevenness processing for rotating the rubber supplied to the extrusion hole around the bead wire is performed on a wall surface of the extrusion hole.

The invention described in claim 2
2. The die plate according to claim 1, wherein the concavo-convex processing is a plurality of ridges extending toward an outlet side of the extrusion hole.

The invention according to claim 3
The die plate according to claim 2, wherein the ridge is formed in a spiral shape on the wall surface of the extrusion hole.

The invention according to claim 4
Used to coat the rubber to the bead wire of stranded wire structure,
The spiral angle of the ridges formed in a spiral shape is set to an angle within ± 1.5 ° with respect to the stranded wire angle of the stranded wire structure bead wire. It is a die plate as described in above.

The invention described in claim 5
5. The die plate according to claim 4, wherein the spiral angle of the ridges formed in a spiral shape is set to the same angle as the twisted wire angle.

The invention described in claim 6
A method for producing a bead wire with rubber, wherein a bead wire with rubber is produced by coating the rubber on the bead wire using the die plate according to any one of claims 1 to 5.
A rubber bead wire is manufactured by coating the bead wire while rotating the rubber by supplying rubber to the die plate while passing the bead wire through the extrusion hole of the die plate. It is a manufacturing method of the bead wire with rubber.

The invention described in claim 7
The bead wire is a stranded wire bead wire,
The method of manufacturing a bead wire with rubber according to claim 6, wherein the bead wire having a twisted wire structure is formed by twisting nine single wire wires having a diameter of 0.38 mm.

The invention according to claim 8 provides:
The method of manufacturing a bead wire with rubber according to claim 6, wherein the bead wire is a single wire.

  According to the present invention, even when the speed at which the bead wire passes through the die plate is increased, the rubber does not peel off, and the bead wire can be manufactured at a high speed. Can be provided.

It is a perspective view which shows the die plate which concerns on embodiment of this invention. It is a transverse cross section showing a die plate concerning an embodiment of the invention. It is a front view which shows the extrusion hole of the die plate which concerns on embodiment of this invention. It is a perspective view which shows the flow of the rubber in the extrusion hole of the die plate which concerns on embodiment of this invention. It is a perspective view which shows the conventional die plate. It is a figure which shows peeling of a coating rubber. It is a figure which shows a strand wire bead wire.

  Hereinafter, the present invention will be described with reference to the drawings based on embodiments.

1. Die plate according to the present embodiment (1) Outline of the present embodiment FIG. 1 is a perspective view showing a die plate according to the present embodiment, FIG. 2 is a transverse sectional view showing the die plate according to the present embodiment, FIG. 3 is a front view showing the extrusion hole of the die plate according to the present embodiment.

  As shown in FIGS. 1 to 3, the die plate A according to the present embodiment tapers from the upstream surface 2 to the downstream surface 3 in the bead wire supply direction, as in the conventional case. A conical extrusion hole 4 is formed, and the supplied bead wire is passed through the extrusion hole 4 together with the rubber, whereby the bead wire is coated with rubber and extruded from the extrusion port 4a.

  In the die plate A according to the present embodiment, the wall surface of the extrusion hole 4 is subjected to uneven processing so that the rubber supplied to the extrusion hole 4 flows while rotating around the bead wire.

  Thereby, since the rubber supplied to the extrusion hole 4 spirally rotates around the bead wire and entangles with the bead wire, even if the speed at which the bead wire passes through the die plate is increased, Rubber can be appropriately attached to the outer peripheral surface of the bead wire.

(2) Details of this Embodiment Hereinafter, the die plate according to this embodiment will be described in detail.

  As shown in FIGS. 1 and 2, the die plate A according to the present embodiment is provided with two extrusion holes 4 penetrating from the upstream surface 2 to the downstream surface 3 in the bead wire supply direction. It has been. Each extrusion hole 4 is formed in a conical shape that tapers from the upstream side toward the downstream side.

  In the die plate A, the bead wire aligned by the baffle is passed through the extrusion hole 4 and the rubber is supplied to the extrusion hole 4 in the same manner as in the prior art. Adhere to make rubber bead wire.

  And as above-mentioned, the die plate A which concerns on this Embodiment is given the uneven | corrugated process to the wall surface of the extrusion hole 4 so that the rubber supplied to the extrusion hole 4 may flow, rotating around a bead wire. It is characterized by being.

  Specifically, as shown in FIGS. 1 and 3, the inner wall of the extrusion hole 4 is provided with a plurality of ridges 5 extending toward the extrusion port 4 a that is the outlet of the extrusion hole 4. Each of the strips 5 is formed in a spiral shape around the extrusion port 4a. When rubber is supplied to the extrusion hole 4 in which the plurality of ridges 5 are formed, the rubber flows in along the ridges 5 and the spiral rubber flow in the extrusion hole 4 as shown in FIG. Occurs. FIG. 4 is a perspective view showing the flow of rubber in the extrusion hole of the die plate according to the embodiment of the present invention.

2. Next, the manufacturing method of the bead wire with rubber | gum using the above-mentioned die plate is demonstrated.

  In the method of manufacturing a bead wire with rubber according to the present embodiment, first, the above-described die plate A is arranged on the downstream side of the baffle, and the space between the baffle and the die plate is filled with rubber. Then, the bead wires aligned by the baffle are passed through the extrusion holes 4 of the die plate A.

  Thereby, a bead wire and rubber are supplied to the extrusion hole 4 of the die plate A, and rubber adheres to the outer peripheral surface of the bead wire. At this time, in the present embodiment, as described above, since the plurality of ridges 5 are formed in a spiral shape on the wall surface of the extrusion hole 4, the rubber supplied to the extrusion hole 4 spirals around the bead wire. It flows while rotating in a shape, and the rubber gets entangled with the bead wire. As a result, the rubber can be properly adhered to the outer peripheral surface of the bead wire, so that even when the speed at which the bead wire passes through the die plate is increased, the rubber does not peel off and the bead wire is Manufacturing can be realized.

3. Other Embodiments In the above, by forming the plurality of ridges 5 in a spiral shape, the rubber supplied to the extrusion hole 4 was allowed to flow while rotating spirally around the bead wire, The present invention is not limited to this.

  For example, even when a plurality of spirally formed grooves (grooves) are formed by cutting the wall surface of the extrusion hole of the die plate, the rubber supplied to the extrusion hole is rotated as described above. It can flow while.

  In addition, the uneven processing applied to the wall surface of the extrusion hole of the die plate does not have to be a ridge or a groove as described above, and a plurality of protrusions and dents are provided so that the rubber can be flowed while rotating. You may provide a fixed space | interval.

  Moreover, it is preferable to set suitably the spiral angle of each protruding item | line 5 currently formed helically according to the kind of bead wire to be used. For example, when using a bead wire W having a twisted wire structure in which a plurality of single wire W2 is twisted as shown in FIG. 6, the twist angle of this twisted wire structure is within ± 1.5 °. It is preferable to set the spiral angle of the ridge 5 shown in FIG.

  As described above, it is difficult for the bead wire having a stranded wire structure to sufficiently spread rubber in the gaps between the single wire wires, and the above-described rubber peeling is likely to occur. By making the angle close to the twist angle, it is possible to form a rubber flow that rotates along the twisted wire of the bead wire, so that rubber is properly attached to each gap of the single wire to prevent the rubber from peeling off. It can be prevented appropriately.

  In particular, among bead wires having a stranded wire structure, a bead wire having a 1 × 9 × 0.38 structure in which nine single wire wires having a diameter of 0.38 mm are twisted together has a rubber peeling as described above in the conventional method. Although it was easy to occur, rubber | gum can be appropriately attached also to such a bead wire and peeling of rubber | gum can be prevented appropriately.

  Also, even if the bead wire used is not a stranded wire structure but a single wire, it can cause the rubber to adhere to the bead wire by causing a flow of rubber that rotates around the bead wire. Therefore, rubber coating can be appropriately performed.

  Further, in the above-described embodiment, the description has been given by taking as an example a die plate in which two extrusion holes are formed. However, the number of extrusion holes is not limited to the present invention, and three or more extrusion holes may be provided. Good.

  Hereinafter, the present invention will be described based on examples.

1. Examples and Comparative Examples (1) Examples 1-7
Based on the above-described embodiment, a bead wire with rubber was manufactured using a die plate in which four protrusions were provided on the wall surface of the extrusion hole. In addition, as the bead wire, a bead wire having a 1 × 9 × 0.38 structure in which nine single wire wires having a diameter of 0.38 mm were twisted and gathered at a twist angle of 2.6 ° was used.

  The spiral angle of the ridges provided spirally and the speed of the bead wire passing through the extrusion hole (coating speed) are as shown in Table 1.

(2) Comparative Examples 1-4
A bead wire with rubber was produced under the same conditions as in Examples 1 to 7, except that a conventional die plate with a smooth wall of the extrusion hole was used and the speed of the bead wire passing through the extrusion hole (coating speed) was used. It was. In addition, the speed (coating speed) of the bead wire passing through the extrusion hole is as shown in Table 1.

2. Evaluation method The outer peripheral surface of the manufactured bead wire with rubber was visually confirmed to evaluate whether or not the rubber was peeled off. The results are shown in Table 1. In addition, the numerical value of the “score” in Table 1 was evaluated assuming that the bead wire with rubber in a state where no rubber was peeled off was 100 and the bead wire with rubber in a state where all the rubber was peeled was 0.

3. Evaluation results From Table 1, when Comparative Example 3 and Example 2 having the same coating speed were compared, Example 2 showed less rubber peeling. In addition, even when other examples with the same coating speed are compared, the same trend results are obtained, and the occurrence of rubber peeling can be prevented by providing uneven processing so that the rubber rotates inside the extrusion hole. Was confirmed.

  In both the comparative example and the example, when the coating speed is increased, there is a tendency that the possibility of occurrence of rubber peeling increases. However, the tendency is less in the example, and the production is performed at a high speed of 25 mm / min. Even in the case of carrying out the process, it is possible to produce a bead wire with rubber in an attached state sufficient for practical use.

  In addition, from the results of Examples 6 and 7, by setting the spiral angle of the ridge within the range of ± 1.5 ° of the bead wire twist angle (1.1 ° to 4.1 °), It can be seen that rubber can be prevented from peeling off by attaching rubber to the bead wire.

  While the present invention has been described based on the embodiments, the present invention is not limited to the above embodiments. Various modifications can be made to the above-described embodiments within the same and equivalent scope as the present invention.

2 upstream surface 3 downstream surface 4 extrusion hole 4a extrusion port 5 ridge 50 (conventional) die plate 51 (conventional) extrusion hole A die plate B rubber peeling G rubber W bead wire W1 rubber bead wire W2 single wire

Claims (8)

A conical extrusion hole tapering from the upstream surface to the downstream surface in the supply direction of the bead wire is formed so as to penetrate the bead wire supplied from the baffle together with the rubber into the extrusion hole. A die plate that coats the bead wire with the rubber by passing it through;
The die plate is characterized in that an unevenness process for rotating rubber supplied to the extrusion hole around the bead wire is applied to a wall surface of the extrusion hole.   2. The die plate according to claim 1, wherein the concavo-convex processing is a plurality of ridges extending toward an outlet side of the extrusion hole.   The die plate according to claim 2, wherein the ridge is formed in a spiral shape on the wall surface of the extrusion hole. Used to coat the rubber to the bead wire of stranded wire structure,
The spiral angle of the ridges formed in a spiral shape is set to an angle within ± 1.5 ° with respect to the stranded wire angle of the stranded wire structure bead wire. The die plate described in 1.   The die plate according to claim 4, wherein a spiral angle of the ridge formed in a spiral shape is set to the same angle as the stranded wire angle. A method for producing a bead wire with rubber, wherein a bead wire with rubber is produced by coating the rubber on the bead wire using the die plate according to any one of claims 1 to 5.
A rubber bead wire is manufactured by coating the bead wire while rotating the rubber by supplying rubber to the die plate while passing the bead wire through the extrusion hole of the die plate. A method for manufacturing a bead wire with rubber. The bead wire is a stranded wire bead wire,
The method for producing a bead wire with rubber according to claim 6, wherein the bead wire having a stranded wire structure is formed by twisting nine single wire wires having a diameter of 0.38 mm.   The said bead wire is a single wire, The manufacturing method of the bead wire with rubber | gum of Claim 6 characterized by the above-mentioned.

Images