JP2012162001A - Method and apparatus for producing pneumatic tire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus and a method for producing a pneumatic tire, each of which can cope easily with molding of a plurality of pneumatic tires having different shapes.SOLUTION: The apparatus for producing the pneumatic tire is constituted so that a tire constitutional member 7, which is arranged adhesively onto the outer circumferential surface of a tire intermediate 1 arranged on a molding drum, is stuck to the outer circumferential surface of the tire intermediate while being pressed by a pair of stitching rolls 8 to mold a green tire and then the pneumatic tire is produced. A plurality of press-contact areas 8a and 8b, which are to be press-contacted, at different inclined angles, with the outside surface of the tire constitutional member 7, are formed on the stitching roll 8. A press-contact area is selected, which is suited to a top shape of the green tire and is excellent in press-contacted states, and the selected press-contact area is pressed to the tire constitutional member.

Description

  The present invention relates to a manufacturing method and a manufacturing apparatus for a pneumatic tire, and particularly to a manufacturing method and a manufacturing apparatus that can easily cope with the formation of a plurality of pneumatic tires having different shapes.

In the production of pneumatic tires, in general, it has a pair of bead cores arranged at a predetermined interval in the width direction of the tire, and a carcass layer that is folded at both ends in the width direction so as to wind the bead core, and is filled with internal pressure. The belt layer and tread rubber (also referred to as “belt and tread rubber”) are placed in close contact with the outer side in the radial direction of the tire intermediate body deformed into a toroidal shape, and then the stitching roll is placed on the outer surface of the tread rubber. The tire intermediate body is rotated around the axis while being pressed, and the stitching roll is moved outward in the axial direction to the end in the width direction of the tread rubber. Thereby, a belt layer and tread rubber are affixed on a tire intermediate body to form a green tire, and then the green tire is vulcanized to produce a pneumatic tire (see Patent Documents 1 and 2).
In this pneumatic tire manufacturing process, in the belt and top attaching process using a stitching roll, stitching is performed while moving the stitching roll as described above, but the shoulder portion of the raw tire is inclined to the raw tire. Stitching rolls with corresponding inclination angles are used.

FIG. 4 is a schematic diagram for explaining a conventional stitching operation, and a top (tread rubber) and a belt (collectively referred to as a green case (tire intermediate body) 1) arranged on a molding drum (not shown). (Referred to as “tire component”) 7 is disposed. For example, a rotating shaft 11 connected to a driving device 10 provided with a motor is attached to the molding drum, and rotates by driving of the driving device 10.
Stitching is performed by pressing the stitching rolls 8 attached to both ends of the support shaft 9 against the tire constituent member 7 (tread rubber) that rotates together with the forming drum, and lowering the stitching rolls 8 while increasing the interval between them. Thereby, as shown in FIG. 4B, the tire constituent member 7 is pasted on the tire intermediate body (green case) to form the raw tire GT.

FIG. 5 is a cross-sectional view schematically showing a stitching roll in a conventional tire manufacturing apparatus.
5A shows a case where the inclination angle (contact surface angle) of the pressure contact area of the stitching roll 8 is a relatively acute angle, and FIG. 5B shows a case where the contact surface angle of the stitching roll 8 is a relatively obtuse angle. Show.
As described above, conventionally, the pressure contact regions 8a and 8b of any one of the stitching rolls are selected and used in consideration of the inclination angle of the end of the tire constituent member 7, and thus the top shape of the green tire GT to be formed. Yes.
If the shape of the stitching roll does not match the top shape of the tire intermediate body 1, the adhesion of the belt and the tread rubber is poor and air is generated, or the tread rubber is damaged. Because.
However, if the stitching roll is replaced in consideration of the top shape of the raw tire, it takes time to replace the stitching roll, which increases the burden of the stitching work, which reduces production efficiency. Another problem arises.

JP 2006-76102 A JP 2006-82389 A

  The present invention has been made in view of the above-described conventional problems, and an object thereof is to replace a stitching roll in stitching for attaching a tire constituent member including at least a tread rubber to a tire intermediate body. In other words, it is possible to improve the productivity of the tire by enabling stitching suitable for a raw tire having a different top shape.

(1) The present invention is a pneumatic tire manufacturing apparatus, which stitches a forming drum, a tire intermediate disposed on the forming drum, and a tire constituent member disposed in close contact with an outer peripheral surface of the tire intermediate. A pneumatic tire manufacturing apparatus including a forming means for forming a raw tire by bonding while pressing with a roll, wherein the stitching roll is different in a pressure contact surface pressed against an outer surface of the tire constituent member A plurality of press contact regions that are press-contacted at an inclination angle are formed.
(2) The present invention is the pneumatic tire manufacturing apparatus described in the above (1), wherein the plurality of pressure contact regions are conical surfaces having different inclination angles with respect to the rotation axis of the stitching roll. And
(3) In the pneumatic tire manufacturing apparatus described in (1) or (2), the forming unit adjusts the position of the stitching roll according to the shape of the green tire to be formed. It has the position adjustment means to perform, It is characterized by the above-mentioned.
(4) The present invention is a method for producing a pneumatic tire, the step of closely attaching a tire constituent member to an outer peripheral surface of a tire intermediate body arranged on a forming drum, and press contact with the outer surface of the tire constituent member The tire constituent member is formed by one pressure contact region of the stitching roll with respect to the outer peripheral surface of the tire intermediate body using a stitching roll in which a plurality of pressure contact regions that are pressed at different inclination angles are formed on the pressure contact surface. And a step of forming a green tire by bonding while pressing.
(5) The present invention is based on the step of adjusting the position of the stitching roll corresponding to the shape of the green tire to be molded in the pneumatic tire manufacturing method described in (4) above. And a step of pressing the selected pressure contact area.

  The present invention has the above-described configuration, and the stitching roll that presses and adheres the tire constituent member including at least the tread rubber to the outer peripheral surface of the tire intermediate body is pressed against the outer surface of the tread rubber. Since a plurality of pressure contact areas that are pressed at different inclination angles are formed, the tire configuration can be selected even when the tire top shape differs by selecting and pressing the optimum pressure contact area according to the top shape of the green tire to be molded. The members can be securely bonded, and can easily cope with the formation of a plurality of different shaped pneumatic tires.

FIG. 1A is a side view showing a contrast between a conventional stitching roll and a stitching roll used in the present invention. FIG. 1A is a conventional stitching roll, and FIG. 1B is a side view of a stitching roll used in the present invention. It is. It is a side view of the modification of the stitching roll used with the tire manufacturing apparatus of embodiment of this invention. It is principal part sectional drawing for demonstrating the stitching operation | movement in this tire manufacturing apparatus using a stitching roll, FIG. 3A uses the case where a small diameter press-contact area | region is used, and FIG. 3B uses a large diameter press-contact area | region. It is the figure which showed the case where there was. It is a schematic diagram explaining the stitching operation | movement in the conventional tire manufacturing apparatus. It is sectional drawing which shows typically the stitching roll in the conventional tire manufacturing apparatus.

Before describing embodiments of the pneumatic tire manufacturing method and manufacturing apparatus of the present invention, first, a stitching roll used in a step of attaching a belt and a tread rubber will be described.
FIG. 1 is a side view showing a contrast between a conventional stitching roll and a stitching roll used in the present invention. FIG. 1A is a conventional stitching roll, and FIG. 1B is a stitching used in the present invention. It is a side view of a roll.
As described above, the conventional stitching roll is formed as a stitching roll having different inclination angles according to the shape (inclination angle) of the top (shoulder portion) of the green tire to be molded (here, the inclination roll). Two types of angles θ of 40 ° and 60 ° are prepared). One is selected from the two types of stitching rolls according to the top shape of the green tire and is attached to the shaft for stitching. The stitching has already been described.

On the other hand, as shown in FIG. 1B, the stitching roll 8 used in the present invention has a configuration in which, for example, the inclined surfaces of the two conventional stitching rolls are integrally provided.
That is, the stitching roll 8 is formed in a substantially truncated cone shape in cross section, and a support shaft 9 (FIG. 3) is rotatably attached along the central axis. The outer peripheral surface of the stitching roll 8 becomes a pressure contact surface pressed against the tire constituent member (tread rubber) 7. On the pressure contact surface of the stitching roll 8, two pressure contact regions 8 a and 8 b made of conical surfaces having different inclination angles with respect to the support shaft 9 that is a rotation shaft are formed. The inclination angle of each pressure contact region 8a, 8b may be set according to the shape of the green tire GT to be molded. For example, the inclination angle of the conical surface of the pressure contact region 8a on the small diameter side is 40 °, and the pressure contact region on the large diameter side The inclination angle of the conical surface 8b is set to 60 °. The stitching roll 8 is attached to both end portions of the support shaft 9 such that the pressure contact region 8a on the small diameter side faces the inside.

  FIG. 2 is a side view of a modified example of the stitching roll 8. In the stitching roll 8, three pressure contact regions 8a, 8b, and 8c made of conical surfaces having different inclination angles are formed on the pressure contact surface that is the outer peripheral surface. The inclination angle of each pressure contact region with respect to the support shaft 9 that is the rotating shaft is, for example, 30 ° for the small diameter side pressure contact region 8a, 45 ° for the intermediate pressure contact region 8b, and 60 ° for the large diameter side pressure contact region 8c. In addition, the inclination angle is set so as to increase from the small diameter side to the large diameter side.

As described above, the stitching roll used in the present invention is configured as a stitching roll (multi-stage stitching roll) having a plurality of press contact regions having different inclination angles, as described above. When stitching is performed, stitching is performed using a pressure contact region having the most appropriate inclined surface among a plurality of inclined surfaces corresponding to the top shape of the raw tire GT. That is, the spacing between the stitching rolls 8 is adjusted, the selected stitching roll surface (contact surface) is pressed against the tire constituent member 7 composed of a tread rubber and a belt, and the stitching roll is maintained while maintaining the pressed state. 8 is lowered and stitching is performed.
This eliminates the need for replacing the stitching roll 8 with respect to the conventional single-stage stitching roll having a single inclined surface (see FIG. 4), so that the stitching work, and thus the tire manufacturing efficiency. Will improve.

Next, with respect to one embodiment of the tire manufacturing method and manufacturing apparatus of the present invention using the stitching roll 8 described above, a drawing is taken here taking as an example the case of manufacturing a raw tire by a so-called two-stage molding method. It explains using.
That is, FIG. 3 is a cross-sectional view of a main part for explaining a stitching operation in the tire manufacturing apparatus using the stitching roll, FIG. 3A shows a case where a small diameter pressure contact region is used, and FIG. It is the figure which showed roughly the case where a large diameter press-contact area | region was used.
As shown in FIG. 3A, an annular tire intermediate body (green case) 1 in which an inner liner, a carcass, a pair of bead cores, a side tread, and the like are combined is attached to the outer peripheral surface of the molding drum. Here, the tire intermediate body 1 is molded in advance with another molding drum and then removed, and the tire intermediate body 1 is fitted and attached to the molding drum. Although not shown in the figure, a driving device 10 is connected to the forming drum via a rotating shaft 11 (FIG. 4) in the same manner as a conventional one (FIG. 4). Rotate around the center.

3A and 3B, in the middle of the tire, the high temperature and high pressure fluid is supplied from the supply device to the inside of the bladder attached to the inner liner, and the axial length of the forming drum is shortened. An outer peripheral surface of the tire intermediate body 1 is formed on an inner peripheral surface of an annular tire constituent member 7 in which a body 1 is bulged outwardly around a molding drum in a toroidal shape, and a belt and a tread rubber that are separately molded are laminated. Is in a fitted state.
Here, the tire constituent member 7 is formed by, for example, laminating two steel belt layers, a spiral belt layer disposed on the outer side in the tire radial direction, and a tread rubber disposed on the outer side in the tire radial direction. It is configured.

Next, by adjusting the distance between the pair of stitching rolls 8, a pressure contact region (pressure contact region 8 b in FIG. 3A) with respect to the tread rubber of the stitching roll 8 is selected, and a pressing mechanism (not shown) attached to the support shaft 9. 2), the stitching roll 8 is lowered on the outer surface of the tire constituent member (tread rubber) 7 and set so as to contact the shoulder portion of the tire intermediate 1.
Next, the driving device 10 is driven to rotate to rotate the molding drum, whereby the tire constituent member 7 rotates about the central axis of the molding drum together with the tire intermediate 1, and the tire constituent member 7 (tread rubber) Stitching is performed by pressing the stitching roll 8 against the outer surface of the sheet and opening the stitching roll 8 outward while lowering the stitching roll 8. As a result, the tire constituent member 7 is pressed and bonded to the tire intermediate 1 and the raw tire GT having the top portion formed in a desired shape is molded.
The molded raw tire GT is conveyed to a vulcanizing device and vulcanized and molded, and a pneumatic tire as a final product is molded.

  In the stitching mechanism shown in FIG. 3B, the press contact region 8b used in FIG. 3A is not used, but instead the press contact region 8a having a smaller outer diameter is used, and here, the spacing between the stitching rolls 8 is increased. This indicates that the pressure contact area is changed. The stitching method is the same as already described.

That is, the pair of stitching rolls 8 is adjusted so that the distance d1 is wider than that shown in FIG. 3A and the inner press contact region 8a is set to press contact with the tire constituent member 7. Then, by rotating the molding drum, the molding operation is performed corresponding to the different top-shaped raw tires.
As for the position adjustment of the stitching roll 8, for example, the stitching roll 8 is attached to the support shaft 9 so as to be movable in the axial direction and adjusted to a desired position, and then fixed to the support shaft 9 by fixing means such as screws. Fix it.
Thus, when selecting an appropriate press-contact area | region from several press-contact area | regions, for example, the position of a pair of stitching rolls 8 is adjusted, the press-contact state of each press-contact area | region with respect to the tire structural member 7 is confirmed, A good pressure contact area should be selected.

According to the present embodiment, it is possible to finely set the inclination angle of the press contact area by adjusting the position of the stitching roll according to the top shape of the green tire to be molded and selecting a plurality of press contact areas. Therefore, the tire manufacturing apparatus can perform stitching on the raw tires having different top shapes using the same stitching roll. That is, the conventional stitching roll replacement work is not required, and the production efficiency can be improved accordingly.
In the above embodiment, the green case used in the so-called two-stage molding method has been described as the tire intermediate body. However, the tire intermediate body is not limited to this, and other rubber molding methods such as various rubbers on a molding drum are used. The stitching roll according to the present embodiment includes all of the intermediate product to be pasted with the tire constituent member, such as an intermediate product when a member is pasted to form a raw tire or a base tire for a retread tire. Are equally applicable.

  1 .. Tire intermediate, 7 .. Tire component, 8 .. Stitching roll, 9 .. Support shaft, 10 .. Drive device, 11.

Claims (5)

A molding drum, a tire intermediate body disposed on the molding drum, and a molding means for molding a green tire by bonding a tire constituent member disposed in close contact with an outer peripheral surface of the tire intermediate body while pressing the tire constituent member with a stitching roll. A pneumatic tire manufacturing apparatus comprising:
The pneumatic tire manufacturing apparatus according to claim 1, wherein the stitching roll has a plurality of pressure contact areas that are pressed at different inclination angles on a pressure contact surface that is pressed against the outer surface of the tire constituent member.   2. The pneumatic tire manufacturing apparatus according to claim 1, wherein the plurality of pressure contact regions are conical surfaces having different inclination angles with respect to a rotation axis of the stitching roll.   The pneumatic tire manufacturing apparatus according to claim 1, wherein the forming unit includes a position adjusting unit that adjusts a position of the stitching roll in accordance with a shape of the green tire to be formed.   A step of closely arranging the tire constituent member on the outer peripheral surface of the tire intermediate body arranged on the forming drum, and a plurality of press contact regions that are in pressure contact at different inclination angles on the press contact surface pressed against the outer surface of the tire constituent member. A step of forming a raw tire by bonding the tire constituent member to the outer peripheral surface of the tire intermediate body while pressing the tire constituent member with one press contact region of the stitching roll using the formed stitching roll. A pneumatic tire manufacturing method characterized by the above.   5. The method according to claim 4, further comprising: adjusting the position of the stitching roll corresponding to the shape of the green tire to be molded; and pressing the pressure contact area selected based on the position adjustment. Pneumatic tire manufacturing method.

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