JP2006088586A - Rubber member and manufacturing process of pneumatic tire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rubber member which can exhaust the air between the rubber member and the carcass treat layer and prevent the bear from generating, and to provide a manufacturing process of a pneumatic tire. <P>SOLUTION: The rubber member is one used for the sidewall portion and one prior to being attached in the tire width direction to the outside of the carcass treat layer that is formed by coating a plurality of cords with rubber. When the surface contacting the carcass treat layer is let to be the inner surface and the surface formed almost parallel to the inner surface the outer surface, the rubber member is equipped with a plurality of holes penetrating from the inner surface to the outer surface, and the diameters of the holes in the inner surface are larger than those in the outer surface. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a rubber member for a pneumatic tire including a sidewall portion outside a carka street layer and a method for manufacturing the pneumatic tire.

  Conventionally, a pneumatic tire is known in which a pair of sidewall portions made of rubber is formed outside a carcass street layer in which a plurality of cords are covered with rubber (for example, Patent Document 1).

A general method for manufacturing a pneumatic tire having a sidewall portion is to extrude rubber using a base having different gauges depending on the position to form a band-shaped rubber member, and the rubber member is placed outside the carka street layer. Paste to. Here, a metallic roller is rotated and moved on the outside of the rubber member, so-called stitching is performed, and air between the rubber member and the carka street layer is pushed out to produce a green tire. Thereafter, the green tire is vulcanized to form a pneumatic tire having a sidewall portion outside the carka street layer.
JP 60-143944 A

  However, in the manufacturing method as described above, the air between the rubber member and the carcass street layer is exhausted only from the gap between the rubber member and the carka street layer, so the air is completely exhausted even when stitching is performed. There is a problem that a bearer is generated in the sidewall portion.

  For this reason, it has been considered that after forming the green tire, a hole is formed in the rubber member using a drill, and air between the rubber member and the carka street layer is discharged from the hole. However, if a hole is formed in the rubber member of the green tire using a drill from the outside, the hole on the outer side of the tire is formed larger than the hole on the inner side of the tire, and external liquid or foreign matter applied to the tire surface is formed in the hole. There was a problem that the rubber member entered and a bear was generated.

  Therefore, it was next considered that the stitching pressure was increased without completely forming the hole as described above, and the air between the rubber member and the carka street layer was completely discharged. When a rubber member having a different gauge is stitched by a high pressure, there is a problem that the rubber member is deformed and leads to generation of a bear.

  Therefore, in view of the above problems, the present invention provides a rubber member and a pneumatic tire manufacturing method capable of discharging air between the rubber member and the carcass street layer and preventing generation of a bear. Is an issue.

  In order to solve the above-mentioned problem, the first feature of the present invention is a rubber member used for a sidewall portion before being attached to the outside in the tire width direction of a carka street layer in which a plurality of cords are covered with rubber, When the surface in contact with the carka street layer is the inner surface and the surface formed substantially parallel to the inner surface is the outer surface, there are a plurality of holes penetrating from the inner surface to the outer surface, and the opening diameter of the inner surface of the hole is the opening diameter of the outer surface The gist of the present invention is that the rubber member is larger than that of the rubber member.

  According to the rubber member according to the first feature, since the rubber member before being attached to the carka street layer is formed with a plurality of holes in which the opening diameter on the inner surface is larger than the opening diameter on the outer surface, When pasting on the street layer, the air between the rubber member and the carka street layer can be discharged from the hole, and the generation of bears can be prevented.

  Moreover, the hole which concerns on the characteristic of this invention is a cone shape, It is preferable that the opening part diameter of the inner surface of a hole is 1-3 mm, and the opening part diameter of the outer surface of a hole is 0.5 mm or less. Since the hole has a conical shape, the opening diameter of the inner surface of the hole is 1 to 3 mm, and the opening diameter of the outer surface of the hole is 0.5 mm or less, the air between the rubber member and the carka street layer The holes can be effectively discharged, and the generation of bears can be further prevented.

  In order to solve the above-described problem, the second feature of the present invention is a method for manufacturing a pneumatic tire including a pair of sidewall portions on the outer side in the tire width direction of a carka street layer in which a plurality of cords are covered with rubber. When the surface in contact with the carka street layer of the rubber member used for the sidewall portion before being attached to the carka street layer is the inner surface and the surface formed substantially parallel to the inner surface is the outer surface, the rubber member penetrates from the inner surface to the outer surface. The gist of the present invention is a method for manufacturing a pneumatic tire, wherein a plurality of holes are formed, and the diameter of the opening on the inner surface of the hole is formed larger than the diameter of the opening on the outer surface.

  According to the method for manufacturing a pneumatic tire according to the second feature, before attaching the rubber member to the carka street layer, the rubber member has a plurality of holes in which the opening diameter of the inner surface of the rubber member is larger than the opening diameter of the outer surface. Since it forms, when sticking a rubber member on a carka street layer, the air between a rubber member and a carka street layer can be discharged | emitted from this hole, and it can prevent generating a bear.

  Moreover, it is preferable that the hole which concerns on the characteristic of this invention is formed from the inner surface of a rubber member with a cone-shaped conical member. Since the hole of the rubber member is formed from the inner surface of the rubber member by the conical member having the conical shape, the opening of the inner surface of the hole can be easily made larger than the opening of the outer surface of the hole, thereby Air between the member and the carka street layer can be discharged, and generation of bears can be prevented.

  Further, the rubber member according to the feature of the present invention is bonded to the carka street layer by rotating the cylindrical member on the outer surface of the rubber member, and the cylindrical member is formed by the moving direction of the cylindrical member and the inclination direction of the hole. The angle is preferably rotated from the acute angle side to the obtuse angle side. Since the angle formed between the moving direction of the cylindrical member and the inclination direction of the hole rotates from the acute angle side to the obtuse angle side, the cylindrical member can discharge the air between the carka street layer and the rubber member more reliably. , It is possible to prevent the bear from occurring.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the rubber member and pneumatic tire which can discharge | emit the air between a rubber member and a carcass street layer, and can prevent generation | occurrence | production of a bear can be provided.

(Configuration of rubber member for pneumatic tire)
Below, the sidewall part 6 formed in the pneumatic tire according to the present embodiment will be described.

  FIG. 1 is a cross-sectional view showing a tire body 1 in the present embodiment.

  The tire body 1 includes a pair of bead portions 2, a carka street layer 3, a belt portion 4, a tread portion 5, and a pair of sidewall portions 6.

  The bead portion 2 is a ring-shaped reinforcing portion for fixing the tire body 1 to a rim (not shown).

  The carka street layer 3 is a skeleton in the tire body 1 in which a plurality of cords are covered with rubber, and is intended to withstand a load, an impact, and the like to maintain the tire structure.

  The belt portion 4 is formed in the circumferential direction between the carka street layer 3 and a tread portion 5 described later, and is used to reinforce the tire body 1 by fastening the carka street layer 3.

  The tread portion 5 is a thick rubber layer that comes into contact with the road surface, and protects the carka street layer.

  The sidewall portions 6 are formed on both side surfaces of the carka street layer 3 in the tire width direction, and are for protecting the carka street layer 3. The sidewall 6 is formed with a plurality of air holes 7 for discharging air accumulated between the carka street layer 3 and the sidewall 6 in the manufacturing process. Here, the side wall portion 6 which is attached to the carka street layer 3 and before being vulcanized is used as a rubber member 60, and the rubber member 60 will be described in detail in FIG.

  FIG. 2 is a view showing the rubber member 60 in the present embodiment. In the following description, the reference numerals of the members related to the tire body 1 and before being vulcanized are two-digit numbers.

  As shown in the figure, both end portions 61 of the rubber member 60 are formed thinner than the central portion 62, and the rubber member 60 has different gauges depending on the position.

  In the figure, the upper surface of the rubber member 60 is the outer surface G, and the surface that is formed substantially parallel to the outer surface G and is in contact with the carka street layer 30 is the inner surface N.

  Further, the rubber member 60 is formed with a plurality of air holes 70 penetrating the outer surface G and the inner surface N for discharging air accumulated between the carka street layer 30 and the rubber member 60 in the manufacturing process.

  FIG. 3 is a side cross-sectional view showing the air hole 70 formed in the rubber member 60 in the present embodiment. In addition, the figure is the figure which looked at the rubber member 60 of FIG. 2 from the A direction.

  As shown in the figure, the opening diameter B (for example, 1 to 3 mm) of the inner surface N of the air hole 70 is formed larger than the opening diameter C (for example, 0.5 mm or less) of the outer surface G.

  In addition, the air hole 70 formed in the rubber member 60 is inclined, and a cylindrical member 9 (for example, a roller 9) that adheres the rubber member to the carka street layer by rotating on the outer surface of the rubber member 60 is provided. The angle formed by the moving direction of the roller 9 and the inclination direction of the air hole 70 rotates from the acute angle side to the obtuse angle side. In addition, in the angle which the roller 9 of the figure and the inclination direction of the air hole 70 make, the angle F is an acute angle and the angle H is an obtuse angle. Therefore, in the same figure, the roller 9 rotates in the D direction. In addition, when the air hole 70 is inclined in the reverse direction, the roller 9 is rotationally moved in the E direction.

(Pneumatic tire manufacturing method)
Below, in the manufacturing method of the pneumatic tire 1 which concerns on this embodiment, it demonstrates, referring FIG.4 and FIG.5.

  In manufacturing the tire main body 1 including the sidewall portion 6 outside the carka street layer 3, first, rubber is extruded by using a base having different gauges depending on the position to form the rubber member 60.

  Next, the air hole 70 is formed in the formed rubber member 60 using a conical member (for example, drill 8). Specifically, as shown in FIG. 4, the air hole 70 is formed by piercing the drill 8 from the inner surface N of the rubber member 60. Since the conical shape 8 is formed from the inner surface N of the rubber member 60, the opening diameter B of the inner surface N of the air hole 70 is formed larger than the opening diameter C of the outer surface G. Further, the hole of the rubber member is formed upward or downward from the inner surface of the rubber member toward the outer surface in accordance with the stitching direction to be described later.

  Next, the formed rubber member 60 is attached to the outer side in the tire width direction of the carka street layer 30 formed in advance. Specifically, as shown in FIG. 5, the rubber member 60 is attached to the outside of the carka street layer 30 and the roller 9 is rotated on the outer surface G of the rubber member 60 to rotate the rubber member 60 to the carka street layer 30. Stitching that is firmly attached to.

  Here, an unvulcanized tire body 10 is formed by attaching the rubber member 60 to the carcass street layer 30, and the uncured tire body 10 is vulcanized, thereby A tire body 1 having a sidewall portion 6 is manufactured.

(Operations and effects of the rubber member and pneumatic tire manufacturing method according to the present embodiment)
According to the rubber member according to the present embodiment, the rubber member before being attached to the carka street layer is formed with a plurality of holes whose inner surface opening diameter is larger than the outer surface opening diameter. When affixing to the layer, air between the rubber member and the carka street layer can be discharged from the hole, and generation of a bear can be prevented.

  Moreover, since the hole which concerns on this embodiment is a cone shape, the opening diameter of the inner surface of a hole is 1-3 mm, and the opening diameter of the outer surface of a hole is 0.5 mm or less, a rubber member and a carka street Air between the layers can be effectively discharged from the hole, and generation of bears can be further prevented. In addition, if the diameter of the opening of the inner surface of the hole formed in the rubber member is 3 mm or more, the rubber of the carka street layer is sucked up so that the rubber member is removed from the original position of the rubber member. When it exists, since the air between a carka street layer and a rubber member cannot be discharged | emitted reliably, the opening part diameter of the inner surface of a hole has preferable 1-3 mm. Further, when the opening diameter of the outer surface of the hole formed in the rubber member is 1 mm or more, it may cause a failure in the sidewall portion such as foreign matter entering the hole or generation of a bear. Therefore, the diameter of the opening on the outer surface of the hole is preferably 1 mm or less.

  According to the method for manufacturing a pneumatic tire according to the present embodiment, before the rubber member is attached to the carka street layer, a plurality of holes are formed in the rubber member in which the opening diameter of the inner surface of the rubber member is larger than the opening diameter of the outer surface. Therefore, when the rubber member is attached to the carcass street layer, the air between the rubber member and the carka street layer can be discharged from the hole, and the generation of a bear can be prevented.

  In addition, since the hole of the rubber member according to the present embodiment is formed from the inner surface of the rubber member by the conical conical member, the opening of the inner surface of the hole can be made larger than the opening of the outer surface of the hole. Thus, air between the rubber member and the carcass street layer can be discharged, and generation of bears can be prevented.

  In addition, since the column member according to the present embodiment has an angle formed by the moving direction of the column member and the inclination direction of the hole rotates from the acute angle side to the obtuse angle side, more air is generated between the carka street layer and the rubber member. It can discharge reliably and can prevent generation | occurrence | production of a bear.

  Examples of the rubber member according to the embodiment of the present invention will be described in detail below.

  A plurality of air holes are formed in the rubber member of the present invention, a pneumatic tire (Example 1) formed using the rubber member is manufactured, and a sidewall portion of the pneumatic tire is peeled off, The number of air reservoirs with a diameter of about 1 mm or more between the Khaka Street layer was investigated. For comparison, a pneumatic tire (conventional example 1) using a rubber member in which no air hole was formed was manufactured and investigated under the same conditions.

The size of the pneumatic tire was 215 / 40R17.

  From the results shown in Table 1, the conventional example 1 had eight air reservoirs, whereas the example 1 had no air reservoirs. Therefore, it was found that air can be prevented from accumulating between the carka street layer and the sidewall portion by forming the air hole in the rubber member.

It is sectional drawing which shows the tire main body which concerns on embodiment of this invention. It is a figure which shows the rubber member which concerns on embodiment of this invention. It is sectional drawing which shows the air hole which concerns on embodiment of this invention. It is a figure which shows the method of forming an air hole in the rubber member which concerns on embodiment of this invention. It is a figure which shows the method to adhere | attach the rubber member which concerns on embodiment of this invention to a carka street layer.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Tire main body 2 ... Bead part 3 ... Carka street layer 4 ... Belt part 5 ... Tread part 6 ... Side wall part 7 ... Air hole 8 ... Drill 10 ... Tire main body 20 ... Bead part 30 ... Carka street layer 40 ... Belt part 50 ... Tread part 60 ... Rubber member 61 ... Both ends 62 ... Central part 70 ... Air hole

Claims (5)

A rubber member used for a sidewall portion before being attached to the outside in the tire width direction of a carcass street layer in which a plurality of cords are covered with rubber,
When the surface in contact with the carka street layer is the inner surface and the surface formed substantially parallel to the inner surface is the outer surface, the surface has a plurality of holes penetrating from the inner surface to the outer surface, and the opening diameter of the inner surface of the hole is A rubber member having a diameter larger than an opening diameter of the outer surface.   2. The hole according to claim 1, wherein the hole has a conical shape, an opening diameter of the inner surface of the hole is 1 to 3 mm, and an opening diameter of the outer surface of the hole is 0.5 mm or less. The rubber member as described. In the manufacturing method of the pneumatic tire provided with a pair of sidewall portions on the outer side in the tire width direction of the carcass street layer in which a plurality of cords are covered with rubber,
When the surface that is in contact with the carka street layer of the rubber member used for the sidewall portion before being attached to the carka street layer is the inner surface, and the surface formed substantially parallel to the inner surface is the outer surface,
A plurality of holes penetrating from the inner surface to the outer surface of the rubber member are formed, and an opening diameter of the inner surface of the hole is formed larger than an opening diameter of the outer surface. Method.   The method for manufacturing a pneumatic tire according to claim 3, wherein the hole is formed from the inner surface of the rubber member by a conical conical member. The rubber member is bonded to the carcass street layer by rotating the cylindrical member on the outer surface of the rubber member, and the cylindrical member has an angle formed by the moving direction of the cylindrical member and the inclination direction of the hole. The method for manufacturing a pneumatic tire according to claim 3, wherein the pneumatic tire rotates from an acute angle side to an obtuse angle side.

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