JP2014100816A - Automatic bead assembling apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an automatic bead assembling apparatus in which occurrence of joint failure of bead apex rubber and adhesion failure between bead core and bead apex rubber can be suppressed upon manufacturing bead.SOLUTION: In an automatic bead assembling apparatus in which bead apex and bead core are jointed by standing plural wing parts to form bead after bead apex rubber is wound to the peripheral part of a former formed by mounting the wing parts as ring-like, at the peripheral surface of the plural wing parts, a taper is mounted so as to rise from the edge of the bead core side to outside. A taper angle α is more than 0° and equal to or less than 15°. The automatic bead assembling apparatus is beneficial especially for tires for a truck and a bus.

Description

  The present invention relates to a bead automatic assembly apparatus that forms a bead by automatically assembling and joining a bead apex rubber of a tire and a bead core.

  When assembling green tires, an automatic bead assembly device is used to automatically assemble a bead apex rubber with a long and narrow cross-sectional shape and a bead core with a polygonal cross-section (usually hexagonal). A bead is formed by bonding (for example, Patent Document 1).

  FIG. 2 schematically shows a main part of a conventional typical bead automatic assembly device. As shown in FIG. 2, the bead automatic assembly device 41 includes a former 42 for winding the bead apex rubber G into a cylindrical shape.

  The former 42 includes a plurality of wings 48 arranged in a ring around the central axis L of rotation, and each wing 48 is a rotation support provided near the bead ring 43 that holds the bead core C. It is configured to stand by rotating about the shaft 44 as a fulcrum.

  The bead formation using the bead automatic assembly apparatus is performed as follows. First, the ring-shaped bead core C is set on the bead ring 43 of the bead automatic assembly device 41. On the other hand, a bead apex rubber G formed into a band shape with a predetermined width is wound around the outer peripheral surface 42 a of the former 42, that is, the outer peripheral surface 48 a of each wing 48.

  The bead apex rubber G wound around the former 42 is then erected together with the wings 48 that are raised by rotating about the rotating support shaft 44, and the bead core with the bottom surface of the bead apex rubber G as the inner peripheral edge. By being joined to the outer peripheral portion of C, a bead is formed.

JP 2002-52624 A

  However, since the former 42 is a flat former in the conventional bead automatic assembling apparatus 41, the bead apex rubber G tends to be spirally wound when the bead apex rubber G having a substantially triangular cross-sectional shape is wound. was there. This was particularly noticeable in the formation of beads for truck and bus tires (TB tires).

  When the bead apex rubber G is wound spirally around the former 42, the winding start end (front end surface) and the winding end end (rear end surface) of the wound bead apex rubber G are shifted. As shown in FIG. 3 (A), joint failure occurs between the front end surface and the rear end surface of the bead apex rubber G, and as shown in FIG. 3 (B), the bead core C and the bead apex rubber There was a problem that a gap was generated between G and poor adhesion occurred.

  And the tire manufactured using the bead which such a joint defect and adhesion defect generate | occur | produced may cause a quality defect.

  Therefore, the present invention provides a bead automatic assembly device capable of suppressing the occurrence of defective joints of a bead apex rubber and poor adhesion between the bead core and the bead apex rubber when manufacturing the beads. And

The invention described in claim 1
A bead apex rubber is wound around the outer periphery of a former formed by arranging a plurality of wings in a ring, and then the wings are erected to join the bead apex and the bead core. A bead automatic assembly device for forming,
The bead automatic assembly apparatus is characterized in that a taper is provided on an outer peripheral surface of the plurality of wings so as to rise outward from an end on the bead core side.

The invention described in claim 2
2. The bead automatic assembly device according to claim 1, wherein the taper angle α satisfies 0 ° <α ≦ 15 °.

The invention according to claim 3
3. The bead automatic assembly device according to claim 1, wherein the taper angle α is 2 ° ≦ α ≦ 8 °. 4.

The invention according to claim 4
The bead automatic assembly device according to any one of claims 1 to 3, wherein the bead automatic assembly device is a device for forming a bead for a truck or bus tire.

  ADVANTAGE OF THE INVENTION According to this invention, the bead automatic assembly apparatus which can suppress generation | occurrence | production of the joint defect of a bead apex rubber and the adhesion defect between a bead core and a bead apex rubber at the time of manufacture of a bead can be provided. .

It is a figure which shows typically the principal part of the bead automatic assembly apparatus which concerns on one embodiment of this invention. It is a figure which shows typically the principal part of the conventional bead automatic assembly apparatus. (A) is a figure which shows typically the joint defect of bead apex rubber, (B) is a figure which shows typically the adhesion defect of bead apex rubber.

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

  FIG. 1 is a main part configuration diagram showing an embodiment of a bead automatic assembly device according to the present embodiment. The bead automatic assembly apparatus 1 includes a former 2, a wing standing mechanism 3, and a bead ring 4.

  The former 2 is for winding the bead apex rubber G into a substantially cylindrical shape, and is disposed in parallel with the central axis L of rotation. The former 2 is composed of a plurality of wings 28 arranged in a ring around the central axis L of rotation.

  The outer peripheral surface 28 a of the plurality of wing portions 28 constitutes the outer peripheral surface 2 a of the former 2. A taper is provided on the outer peripheral surface 28a of the plurality of wings 28 so as to rise outward from the end on the bead core C side.

  Since the outer peripheral surface 28a of the wing portion 28 is tapered, even if the bead apex rubber G having a substantially triangular cross-sectional shape is wound around the outer periphery of the former 2, it is not wound spirally. As a result, joint failures and adhesion failures that have conventionally occurred can be suppressed.

  The taper angle α may be set as appropriate depending on the shape and size of the bead apex rubber G, but in order to cope with the bead apex rubber G of various shapes / sizes, 0 ° <α ≦ 15 It is preferable that the angle is set in the range of °.

  When the taper angle α is 0 °, that is, in the case of a conventional former, as described above, frequent joint failures and adhesion failures are caused. On the other hand, in the case of a former in which α is set to exceed 15 °, the joint portion is displaced in the opposite direction to the conventional case, and there is a high possibility that joint failure or adhesion failure is caused.

  A more preferable taper angle α is 2 ° ≦ α ≦ 8 °. In this case, the above-described effects can be remarkably exhibited.

  The wing standing mechanism 3 rotates all the wings 28 around the rotation support shaft 34 provided at the end of the former 2 on the bead core C side by the driving device 36 via the plurality of levers 35. Can stand up. That is, when the plurality of levers 35 are simultaneously moved forward with a predetermined stroke S by the driving device 36, all the wings 28 rotate and stand up with the rotating support shaft 34 as a fulcrum as indicated by a dotted line. To do. On the other hand, when the plurality of levers 35 are simultaneously moved backward with a predetermined stroke S by the drive device 36, all the wings 28 are tilted with the rotation support shaft 34 as a fulcrum so as to be displayed as indicated by the solid line. Return to state.

  The bead ring 4 is for holding the bead core C, and is disposed at the end of the former 2 on the bead core C side (left side in FIG. 1).

  A bead is formed by supplying a bead core C having a ring shape and a belt-shaped bead apex rubber G having a predetermined width to the bead automatic assembly apparatus 1 having the above-described configuration.

  Specifically, the bead apex rubber G having a substantially triangular cross-sectional shape has an outer peripheral surface 2a of the former 2, that is, a plurality of pieces, such that the bottom side is disposed at the end of the former 2 on the bead core C side. It is wound around the outer peripheral surface 28a of the wing portion 28. At this time, since the outer peripheral surface 28a of the wing portion 28 is tapered as described above, it does not wind spirally, and the occurrence of joint failure and adhesion failure is suppressed.

  Next, in a state where the bead apex rubber G is wound around the outer peripheral surface 2a of the former 2, the wing raising mechanism 3 operates, and the drive device 36 advances the plurality of levers 35 at a predetermined stroke S all at once. Move. As a result, as shown by the dotted line, all the wings 28 stand up with the rotation support shaft 34 as a fulcrum, and as a result, the bead apex rubber G is expanded on the other side while keeping the inner diameter on one side. The whole is formed into a donut plate shape and joined to the outer periphery of the bead core C set on the bead ring 43. This completes the bead formation.

  In the obtained bead, since the bead apex rubber G is suppressed from occurrence of joint failure and adhesion failure, a tire manufactured using such a bead can exhibit stable quality.

  In addition, since the bead apex rubber of the tire for TB (truck tire, bus tire) is thick, in the conventional bead automatic assembly device, the bead apex rubber was particularly easy to be spirally wound around the former. . However, by using the bead automatic assembly device of the present embodiment, it is possible to remarkably exhibit the effect of suppressing the occurrence of joint failure and adhesion failure when forming beads.

1. Example and Comparative Example 22.5-63S / 1 bead core, hard layer, and packing layer using a bead automatic assembly device in which a former is formed with wings having a taper of angle α shown in Table 1 on the outer peripheral surface A bead was formed from a bead apex rubber composed of

  The assembly operation by each bead automatic assembly device was repeated for one day, and the occurrence state of defective products was evaluated.

  Specifically, we evaluated the finished condition of the bead obtained, such as joint failure at the joint between the front and rear end surfaces of the bead apex rubber and poor adhesion between the bead core and the bead apex rubber at the joint. did.

  The results are shown in Table 1. In Table 1, “◎” indicates a defective product rate of less than 1%, “◯” indicates a defective product rate of 1% to less than 3%, and “×” indicates a defective product rate of 3% or more. It shows that it was.

  From Example 1 to Example 6 in Table 1, when the taper angle α of the outer peripheral surface of the wing portion is 0 ° <α ≦ 15 °, joint failure of the joint portion between the front end surface and the rear end surface of the bead apex rubber It can also be seen that the occurrence of poor adhesion between the bead core and the bead apex rubber at the joint is sufficiently suppressed.

  In particular, from Examples 2 to 4, it can be seen that when the taper angle α of the outer peripheral surface is 2 ° ≦ α ≦ 8 °, the occurrence of joint failure or adhesion failure is further suppressed.

  Further, it can be seen from Comparative Example 1 that when the taper angle α of the outer peripheral surface is α = 0 ° as in the prior art, the occurrence of joint failure and adhesion failure cannot be sufficiently suppressed.

  Further, it can be seen from Comparative Example 2 that even when the taper angle α of the outer peripheral surface is too larger than 15 °, the occurrence of joint failure or adhesion failure cannot be sufficiently suppressed.

  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.

DESCRIPTION OF SYMBOLS 1,41 Bead automatic assembly apparatus 2,42 Former 2a, 42a Former's outer surface 3 Feather standing mechanism 4,43 Bead ring 28,48 Feather 28a, 48a Feather's outer surface 34,44 Rotating support shaft 35 Lever 36 Drive unit C Bead core G Bead apex rubber α Taper angle L Center axis S Stroke

Claims (4)

A bead apex rubber is wound around the outer periphery of a former formed by arranging a plurality of wings in a ring, and then the wings are erected to join the bead apex and the bead core. A bead automatic assembly device for forming,
A bead automatic assembly apparatus, wherein a taper is provided on an outer peripheral surface of the plurality of wings so as to rise outward from an end portion on the bead core side.   The bead automatic assembly device according to claim 1, wherein the taper angle α satisfies 0 ° <α ≦ 15 °.   The bead automatic assembly apparatus according to claim 1 or 2, wherein the taper angle α satisfies 2 ° ≦ α ≦ 8 °.   The bead automatic assembling apparatus according to any one of claims 1 to 3, wherein the apparatus is a device for forming a bead of a tire for trucks and buses.

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