JP6254790B2 - Green tire prototype method - Google Patents

Description

  The present invention relates to a green tire trial manufacturing method.

  Conventionally, when a green tire is vulcanized and molded, the green tire is placed in a mold, and a bladder is inserted into the green tire to be inflated.

  However, there is no method for confirming whether or not the rubber flow is properly performed in the vulcanization molding process of the green tire.

  The present invention makes it possible to verify whether or not the rubber flow is properly performed when vulcanizing and molding a green tire, and to prevent the occurrence of product defects such as bare, air-filled, and flow cracks. And

As a means for solving the above problems, the present invention provides:
A first step of forming a pattern composed of a plurality of marks so that the marks are aligned in the radial direction of the green tire;
A second step of vulcanizing and molding the green tire formed with the pattern;
I have a,
The pattern provides a green tire trial manufacturing method characterized in that the pattern is formed of a seal that can be attached to a green tire.
According to this, it is possible to easily grasp the rubber flow in the radial direction of the green tire during vulcanization molding from the tire pattern obtained in the second step. Moreover, the rubber flow by vulcanization molding can be grasped only by sticking the seal on the green tire.

As a means for solving the above problems, the present invention provides:
A first step of forming a pattern composed of a plurality of marks so that the marks are aligned in the radial direction of the green tire;
A second step of vulcanizing and molding the green tire formed with the pattern;
Have
A green tire trial production method is provided, wherein the pattern has a color distinguishable from a green tire.
According to this, it is possible to easily grasp the rubber flow in the radial direction of the green tire during vulcanization molding from the tire pattern obtained in the second step. In addition, the rubber flow can be grasped at a glance, and even when it enters the inside of the tire, it can be easily discriminated by cutting.

  It is preferable that the mark of the pattern is symmetrical about at least a straight line orthogonal to a straight line extending in the radial direction of the green tire.

  According to this, it becomes possible to grasp the rubber flow in the radial direction of the green tire more accurately.

  In the first step, it is preferable to form a pattern composed of a plurality of marks so that the marks are aligned in the circumferential direction of the green tire.

  According to this, it is possible to easily grasp the rubber flow in the circumferential direction of the green tire at the time of vulcanization molding from the tire pattern obtained in the second step.

  The mark of the pattern is preferably symmetric about a straight line extending in the radial direction of the green tire.

  According to this, it becomes possible to grasp the rubber flow in the circumferential direction of the green tire more accurately.

  The marks of the pattern are preferably adjacent to each other in point or line contact.

  According to this, it can classify | categorize by the mark which carries out a point or a line contact, without an overlap and a clearance gap, and it becomes possible to grasp | ascertain rubber flow more correctly.

  It is preferable to give a continuous number to the marks of the pattern from one end side to the other end side to be aligned.

  According to this, it is possible to grasp at a glance in which region the rubber flow is generated divided by the mark.

  The mark of the pattern is preferably a perfect circle.

  According to this, it is possible to grasp the rubber flow in both the radial direction and the circumferential direction of the green tire.

  The pattern preferably has a color distinguishable from the green tire.

  According to this, the rubber flow can be grasped at a glance, and even when it enters the inside of the tire, it can be easily discriminated by cutting.

  According to the present invention, the rubber flow at the time of vulcanization molding can be easily grasped by providing a pattern comprising a plurality of marks aligned in the radial direction of the green tire. Therefore, appropriate vulcanization molding can be performed by changing the green tire molding conditions and the like from the next time on the basis of the obtained pattern change.

It is a fragmentary sectional view showing the outline of the trial production green tire concerning this embodiment. It is a fragmentary sectional view which shows the outline of the tire obtained by vulcanization-molding the green tire shown in FIG. (A) is a front view of the seal for green tire trial manufacture concerning this embodiment, (b) is a front view which shows an example of the state after the vulcanization molding. (A) to (d) is a front view of a seal for trial production of a green tire according to another embodiment.

  Embodiments according to the present invention will be described below with reference to the accompanying drawings. In the following description, terms indicating specific directions and positions (for example, terms including “up”, “down”, “side”, “end”) are used as necessary. Is for facilitating understanding of the invention with reference to the drawings, and the technical scope of the present invention is not limited by the meaning of these terms. Further, the following description is merely illustrative in nature and is not intended to limit the present invention, its application, or its use.

  FIG. 1 is a cross-sectional view of a green tire 1 according to this embodiment. The green tire 1 includes an inner liner 2, a bead core 3, a belt 4, a sidewall 5, a tread 6, and the like (other members are omitted in FIG. 1). The green tire 1 is set in a mold, and a tire 7 is formed by bulging and molding a bladder inserted on the inner peripheral side. FIG. 2 shows a sectional view of the radial tire.

  By the way, before the green tire 1 is molded and the tire 7 is vulcanized and molded, it is verified whether or not the rubber flows properly during the vulcanization molding as follows. In this embodiment, a green tire trial seal 8 is attached to the side portion 10 of the green tire 1 and vulcanized.

  The seal 8 may be made of a material having a melting point that is not melted by vulcanization molding, which will be described later, and that can be elastically deformed according to its movement when a rubber flow occurs during vulcanization molding of the green tire 1. Specifically, an NR transfer film in which a natural (NR) rubber is formed into a film having a thickness of 0.05 mm, for example, can be used. As shown in FIG. 3A, a pattern in which marks 9 made of a perfect circle having a diameter of 10 mm are arranged in two rows in the longitudinal direction is printed on the surface of the seal 8. The perfect circles adjacent to each other in the longitudinal direction and the width direction are arranged so as to make point contact. A serial number (0 to 9) is printed from one end side to the other end side of the seal 8 in the perfect circle. Note that the serial number is not limited to numbers, and other symbols such as alphabets may be added (for example, a, b, c, etc.). In short, any symbol that can identify each mark may be used.

  The seal 8 having the above configuration is attached to the side portion 10 and the bead portion 11 of the green tire 1 along the radial direction. The sticking position may be the entire side part 10 and the bead part 11, or may be the upper half part, the lower half part, or the intermediate part of the side part 10. Furthermore, a shoulder portion 12 can be included.

  In the seal 8 attached to the side portion or the like of the green tire 1 in this way, each mark 9 is a perfect circle and is symmetrical with respect to any straight line passing through the center thereof. In particular, it is symmetrical with respect to a straight line extending in the radial direction of the green tire 1 and a straight line orthogonal to the straight line, which is convenient for verifying the rubber flow after vulcanization molding.

  The green tire 1 to which the seal 8 is attached is placed in a mold. At this time, a bladder is inserted into the inner diameter side of the green tire 1. Then, vulcanization molding is performed by closing the mold and inflating the bladder.

  FIG. 3B shows the state of the seal 8 in the tire 7 obtained by vulcanization molding. In this example, the seal 8 was stuck from the lower side of the side portion 10 of the green tire 1 to the bead portion 11 and vulcanized. After vulcanization molding, the seal 8 has a number between 0 and 1 (indicated by arrow a in the figure), between 2 and 3 (indicated by arrow b in the figure), between 5 and 6 (indicated by arrow c in the figure). It can be seen that an appropriate rubber flow is not obtained. For example, between the numbers 2 and 3 and between 5 and 6, the boundary portions overlap and are crushed in the longitudinal direction. That is, it can be estimated that a so-called flow crack is generated by biting into the side portion 10 of the obtained tire 7.

  In addition, as a result of vulcanization molding, defects generated in the tire 7 include bear (scratches and burns) and air in addition to the biting. For example, the burn can be determined from a change in surface gloss, such as fading of characters on the seal 8. It can be inferred that the air entry occurs at a location where the marks 9 in each region overlap, such as between the numbers 2 and 3, 5 and 6. In addition, when air enters near the tire surface, swelling occurs on the surface. Therefore, it can be presumed that the air has entered from the visual form of the mark 9 that has changed due to the swelling.

  Thus, if the state of each mark 9 of the seal 8 in the tire 7 after vulcanization molding is observed, the state of the rubber flow at the time of vulcanization molding can be accurately grasped. In particular, each mark 9 is point-contacted and continuously provided in both the radial direction and the circumferential direction, and is given a number so that it can be grasped at a glance where the trouble has occurred. Can do. Therefore, based on this result, adjustment work is performed to adjust the length of the material to be used or to correct the mold structure. In the modification of the mold structure, inappropriate rubber flow is prevented by adjusting the ease of rubber flow by changing the position and number of vent holes.

  If the adjustment operation is completed and vulcanization molding is performed again, the state of rubber flow can be improved. In this case, the vulcanization molding with the seal 8 attached may be performed again. In the vulcanization molding after the adjustment work is performed in this way, it is possible to prevent the occurrence of the above-mentioned problems (biting, entering air, burning) by making the rubber flow appropriate.

  In addition, this invention is not limited to the structure described in the said embodiment, A various change is possible.

In the embodiment, the pattern is formed by laying out the circular mark 9 so as to make point contact in the radial direction and the circumferential direction of the green tire 1, but as shown in FIG. A gap corresponding to one perfect circle may be provided in the middle width direction. Further, as shown in FIG. 4B, a gap corresponding to one perfect circle may be provided in the vertical direction in the figure.
In the above-described embodiment, the pattern is formed by the perfect circle mark 9. However, the pattern may be configured as shown in FIGS. 4C and 4D. However, if it is a perfect circle, even if the green tire prototype seal 8 is attached to the side portion 10 and the bead portion 11 of the green tire 1, It is possible to verify whether the rubber flow in the radial direction and the circumferential direction is appropriately performed.

In FIG.4 (c), the serial number (0-9) is attached | subjected toward the other end side from the one end side of what is located in the center among the frame lines formed in the grid | lattice form.
In FIG. 4D, a scale is formed at a predetermined pitch with respect to a straight line, and a number increasing from 0 to 10 is added to the side of each scale up to 100.

  Moreover, in the said embodiment, although the pattern which consists of several marks 9 was printed on the sheet | seat and this seal | sticker 8 was stuck on the green tire 1, it is also possible to comprise as follows.

That is, the pattern may be directly printed on the green tire 1 or may be formed on a color rubber other than black.
In the former case, for example, a transfer technique can be used.
In the latter case, a colored rubber having a thickness of about 0.3 to 0.4 mm may be attached. When colored rubber is used, it is preferable in that the intrusion state can be easily grasped by cutting the tire 7 even when the surface portion enters the inside due to the rubber flow.

DESCRIPTION OF SYMBOLS 1 ... Green tire 2 ... Inner liner 3 ... Bead core 4 ... Belt 5 ... Side wall 6 ... Tread 7 ... Tire 8 ... Seal 9 ... Mark 10 ... Side part 11 ... Bead part 12 ... Shoulder part

Claims (8)

A first step of forming a pattern composed of a plurality of marks so that the marks are aligned in the radial direction of the green tire;
A second step of vulcanizing and molding the green tire formed with the pattern;
Have
The green tire trial production method, wherein the pattern is constituted by a seal that can be attached to a green tire. A first step of forming a pattern composed of a plurality of marks so that the marks are aligned in the radial direction of the green tire;
A second step of vulcanizing and molding the green tire formed with the pattern;
Have
The green tire trial manufacturing method, wherein the pattern has a color distinguishable from the green tire.   3. The green tire trial manufacturing method according to claim 1, wherein the marks of the pattern are symmetrically formed at least about a straight line orthogonal to a straight line extending in a radial direction of the green tire.   4. The method according to claim 1, wherein in the first step, a pattern including a plurality of marks is formed so that the marks are aligned in a circumferential direction of the green tire. 5. Green tire prototype method.   5. The green tire trial production method according to claim 3, wherein the mark of the pattern is symmetric about a straight line extending in a radial direction of the green tire.   6. The green tire trial production method according to claim 1, wherein the marks of the pattern are adjacent to each other in point or line contact.   The green tire prototype method according to any one of claims 1 to 6, wherein a serial number is assigned to the mark of the pattern from one end side to the other end side to be aligned.   The green tire trial production method according to claim 1, wherein the mark of the pattern is a perfect circle.

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