JP6577798B2 - PRESSING ROLLER AND METHOD FOR MANUFACTURING TIRE COMPONENT - Google Patents

Description

  The present disclosure relates to a presser roller and a method for manufacturing a tire constituent member using the presser roller.

  As a step of forming the tire constituent member, there is a step of pressing the tread rubber to a member (belt or the like) to be disposed on the inner peripheral side of the tread rubber. In this step, the pressing roller is rolled in the circumferential direction while pressing the outer peripheral surface of the tread rubber.

  As schematically shown in FIG. 4, the tread rubber T often has a concavo-convex shape with a thicker shoulder region T2 around the center portion T1 in the width direction. When the hardness is pressed by the roller R having a constant hardness, the pressing force at the thick portion of the tread rubber T is increased, and the pressing force at the thin portion is decreased. Then, the pressing force at the center portion T1 (center) in the width direction of the tread rubber T is weak, the pressing force at the shoulder region T2 is increased, and force is applied from both sides to the center CL in the width direction of the tread rubber T. As a result, the pressing force is not uniform. If the tread rubber is soft and thin, the rubber is pushed in a direction where the pressing force is weak and wrinkles are formed. In some cases, the tread rubber center marker may meander along the circumferential direction, or the tread rubber center marker may be displaced. Further, if a force is applied from both sides to the center in the width direction of the tread rubber, the air entrapped in the member may not be released and gather in the center, leading to a molding defect.

  As one of means for extracting air, Patent Document 1 discloses that a shaft held at both ends, a cylindrical elastic body covering the outer periphery of the shaft, and an outer peripheral surface of the cylindrical elastic body are supported in the axial direction. There is disclosed a press roller having a plurality of rings arranged in a ring, and the outer diameter of the plurality of rings gradually decreases from the axial center to the outer side in the axial direction. According to this configuration, the outer diameter of the ring at the center in the axial direction is larger, and the outer diameter of the ring is smaller toward the outer side. Therefore, the air is directed from the center to the outer side in the axial direction by the convex shape due to the outer diameter difference. (See paragraph 0017).

JP 2008-87375 A

  However, the press roller described in Patent Document 1 has a step on the outer surface of the roller formed by the outer peripheral surfaces of a plurality of rings, and if a force acts in the axial direction even at the time of rolling, the press roller is caught by this step, The ring sways in the axial direction and the pressing force escapes, preventing the tread rubber from being pushed properly.

  The present disclosure has been made paying attention to such a problem, and the purpose thereof is to appropriately press the tread rubber even when force is applied in the axial direction during rolling, and to prevent and prevent the center shift. It is to provide a presser roller capable of realizing easy air bleeding and a method of manufacturing a tire constituent member using the presser roller.

  In order to achieve the above object, the present disclosure takes the following measures.

The presser roller of the present disclosure is a presser roller that rolls along the circumferential direction while pressing the outer peripheral surface of the tread rubber,
A shaft held at both ends;
A cylindrical elastic body covering the outer periphery of the shaft;
A plurality of rings supported on the outer peripheral surface of the cylindrical elastic body and arranged in the axial direction;
The plurality of rings have the same outer diameter,
The hardness of the cylindrical elastic body decreases from the center in the axial direction toward the outside in the axial direction.

  In this way, since the outer diameters of the plurality of rings are the same, there is no step on the outer surface of the presser roller formed by the outer peripheral surfaces of the plurality of rings, and even if a slight force is applied in the axial direction during rolling. The tread rubber can be appropriately pressed without being caught. Nevertheless, the ring is allowed to be displaced in the radial direction due to the elastic deformation of the cylindrical elastic body, and the hardness of the cylindrical elastic body supporting the ring is high and hard in the axial center, and decreases toward the outer side in the axial direction. Since it becomes softer, the pressing force at the center in the axial direction becomes stronger than the pressing force at the outer side in the axial direction, the center portion of the tread rubber can be accurately pressed, and center deviation can be prevented. Furthermore, since a force acts from the center of the tread rubber toward the outside, air can be appropriately removed.

The presser roller of the present disclosure is a presser roller that rolls along the circumferential direction while pressing the outer peripheral surface of the tread rubber,
A shaft held at both ends;
A cylindrical elastic body covering the outer periphery of the shaft;
A plurality of rings supported on the outer peripheral surface of the cylindrical elastic body and arranged in the axial direction;
The plurality of rings have the same outer diameter,
The thickness of the cylindrical elastic body increases from the center in the axial direction toward the outside in the axial direction.

  As described above, when the cylindrical elastic body becomes thick, the pressing force becomes weak, and when the cylindrical elastic body becomes thin, the pressing force becomes strong. The pressing force at the center in the axial direction becomes stronger than the pressing force at the outer side in the axial direction, and the center portion of the tread rubber can be pressed accurately, and the center shift can be prevented. Furthermore, since a force acts from the center of the tread rubber toward the outside, air can be appropriately removed.

  The tire component manufacturing method according to the present disclosure includes a step of forming a tread rubber and a member to be disposed on an inner peripheral side of the tread rubber, a step of disposing the tread rubber above the member, and the presser described above. Rolling along the circumferential direction while pressing the outer peripheral surface of the tread rubber with a roller, and crimping the tread rubber to the member.

Sectional drawing which shows the pressing roller of 1st Embodiment. Sectional drawing which shows the pressing roller of 1st Embodiment. Sectional drawing which shows the pressing roller of 2nd Embodiment. Explanatory drawing regarding the malfunction of the conventional presser roller.

<First Embodiment>
The presser roller 1 according to the first embodiment of the present disclosure will be described with reference to FIGS. The presser roller 1 rolls along the circumferential direction while pressing the outer peripheral surface of the tread rubber. The center in the width direction of the outer surface of the tread rubber is pressed by the axial center 1a of the roller 1.

  FIG. 1 is a cross-sectional view showing the presser roller 1 in a natural state where no tread rubber is pressed. As shown in FIG. 1, the presser roller 1 includes a shaft 2 that is rotatably supported at both ends by a roller travel device (not shown), a cylindrical elastic body 3 that covers the outer periphery of the shaft 2, and a cylindrical elastic body. 3 and a plurality of rings 4 arranged in the axial direction AD. Since the ring 4 is fixed to the shaft 2 via the cylindrical elastic body 3, radial displacement is allowed by elastic deformation of the cylindrical elastic body 3. Each ring 4 is displaced in the radial direction independently of the other ring 4. The plurality of rings 4 are sandwiched by the ring fixing portions 5 from both sides in the axial direction, and movement in the axial direction AD is restricted.

  The plurality of rings 4 have the same outer diameter and inner diameter, and all have the same hardness. In the present embodiment, the ring 4 is made of plastic, but is not limited thereto, and may be formed of other materials. For example, resin or metal may be used.

  The cylindrical elastic body 3 is formed so that the hardness decreases as it goes from the axial center CL toward the axial outer side OUT. In this embodiment, urethane rubber is used, but other elastic bodies such as rubber, sponge, and resin can be used as long as they can be elastically deformed. In order to appropriately exhibit the radial displacement of the ring 4, the JISA hardness is preferably in the range of 30 ° to 15 °.

  In the present embodiment, as shown in FIG. 2, the cylindrical elastic body 3 is formed of rubber having four different hardnesses, and the rubber hardness gradually decreases from the axial center CL toward the axially outer side OUT. Specifically, as shown in FIG. 2, the range of less than 17.5% of the width W of the tread rubber from the axial center CL to the axial outer side OUT of the cylindrical elastic body 3 has a JISA hardness of 30 °. is there. In the range of 17.5% or more and less than 32.5% of the width W of the tread rubber, the JISA hardness is 25 °. In the range of 32.5% or more and less than 42.5% of the width W of the tread rubber, the JISA hardness is 20 °. In the range of 42.5% or more of the width W of the tread rubber, the JISA hardness is 15 °. If it is this numerical range, it can respond to the shape of various tread rubber. This is a preferred range and is not limited to this.

  According to the said structure, the hardness of the cylindrical elastic body 3 is high and hard, and the hardness of the cylindrical elastic body 3 is low and soft. Since the thickness of the cylindrical elastic body 3 is the same, the pressing force due to the elastic repulsion force of the cylindrical elastic body 3 is stronger in the center in the axial direction than in the outer side in the axial direction. As a result, the pressing force against the central portion of the tread rubber can be increased compared to the outside in the width direction.

  In the example illustrated in FIG. 2, the cylindrical elastic body 3 has four different hardnesses, and the hardness gradually decreases from the axial center CL toward the axially outer side OUT, but is not limited thereto. The cylindrical elastic body 3 only needs to have at least three different hardnesses. When the cylindrical elastic body 3 has only two different hardnesses, it is difficult to obtain the above effect. For example, the hardness of the cylindrical elastic body 3 is a JISA hardness of 15 ° or more and 30 ° or less, and may be reduced by 1 ° for each ring from the axial center CL toward the axial outer side OUT.

  The manufacturing method of the cylindrical elastic body 3 is formed while winding urethane rubber around the shaft 2. When changing the hardness, the rubber to be wound may be changed to one having a different hardness.

  In order to show the configuration and effects of the present disclosure, the following evaluations were performed on the following examples.

(1) Evaluation of Center Displacement A tread rubber with a center marker was pressed against a belt with a roller to generate a predetermined number of unvulcanized tire constituent members. It was confirmed whether a center shift occurred.

Comparative Example 1
As shown in FIG. 1, a pressing roller having a plurality of rings having the same outer diameter and inner diameter and having a cylindrical elastic body 3 having a JIS hardness of 30 ° was produced. Center misalignment evaluation was performed using this roller.

Example 1
A presser roller shown in FIG. 2 was produced. Center misalignment evaluation was performed using this roller.

Example 2
A presser roller was produced in which the cylindrical elastic body 3 ′ supporting the ring 4 ′ corresponding to the center CL in the axial direction had a JISA hardness of 30 ° and decreased by 1 ° for each ring toward the outer side OUT in the axial direction. Center misalignment evaluation was performed using this roller.

  As a result of the center shift evaluation, in Comparative Example 1, a tread rubber serving as a center shift was generated, whereas in Examples 1 and 2, no tread rubber serving as a center shift was generated. Therefore, it can be understood that the roller of the present disclosure is more effective in preventing the center deviation than the conventional roller.

As described above, the presser roller of the first embodiment is
A presser roller 1 that rolls along the circumferential direction while pressing the outer peripheral surface of the tread rubber T,
A shaft 2 held at both ends, a cylindrical elastic body 3 covering the outer periphery of the shaft 2, and a plurality of rings 4 supported on the outer peripheral surface of the cylindrical elastic body 3 and arranged in the axial direction AD, The plurality of rings 4 have the same outer diameter, and the hardness of the cylindrical elastic body 3 decreases from the axial center CL toward the axially outer side OUT.

  Thus, since the outer diameters of the plurality of rings 4 are the same, there is no step on the outer surface of the presser roller 1 formed by the outer peripheral surfaces of the plurality of rings 4, and a slight force is exerted in the axial direction AD during rolling. Even if it acts, the tread rubber T can be appropriately pressed without being caught. Nevertheless, the ring 4 is allowed to be displaced in the radial direction by the elastic deformation of the cylindrical elastic body 3, and the cylindrical elastic body 3 that supports the ring 4 has a high axial center CL and is hard. Since it becomes smaller and softer toward the outer side OUT, the pressing force at the axial center CL becomes stronger than the pressing force at the axial outer side OUT, so that the center part of the tread rubber T can be accurately pressed, and center deviation can be prevented. Further, since a force acts outward from the central portion of the tread rubber T, air can be appropriately removed.

  In the first embodiment, the cylindrical elastic body 3 has at least three different hardnesses, and the hardness gradually decreases from the axial center CL toward the axially outer side OUT. The above effect is hardly exhibited by two-stage hardness change. As in this configuration, the effect can be exhibited if the hardness change is at least in three stages.

  In the first embodiment, the cylindrical elastic body 3 has four different hardnesses, and the hardness gradually decreases from the axial center to the axially outer side. If the hardness change is large, the effect is easily exhibited, but it is costly to change the hardness. Therefore, it is possible to achieve both the securing of effects and cost reduction.

  In the first embodiment, the range of less than 17.5% of the width W of the tread rubber from the axial center CL of the cylindrical elastic body 3 toward the axially outer side OUT has a JIS hardness of 30 °, 17.5% or more and 32. The range of less than 5% has a JISA hardness of 25 °, the range of 32.5% to less than 42.5% has a JISA hardness of 20 °, and the range of 42.5% or more has a JISA hardness of 15 °. The above configuration is cited as one of the preferred embodiments of the present disclosure.

  In the first embodiment, the cylindrical elastic body 3 decreases in hardness for each ring 4 from the axial center CL toward the axially outer side OUT. According to this configuration, since the hardness is reduced for each ring, a force is easily applied to the side from the central portion of the tread rubber T, which is advantageous for the air bleeding effect.

The tire component manufacturing method according to the first embodiment includes a step of forming the tread rubber T and a member to be disposed on the inner peripheral side of the tread rubber,
Disposing the tread rubber above the member;
A step of rolling the tread rubber along the circumferential direction while pressing the outer peripheral surface of the tread rubber with the presser roller 1 according to the first embodiment, and pressing the tread rubber against the member.

According to this method, since the outer diameters of the plurality of rings 4 are the same, there is no step on the outer surface of the presser roller 1 formed by the outer peripheral surfaces of the plurality of rings 4, and slightly in the axial direction AD during rolling. Even if force is applied, the tread rubber T can be appropriately pressed without being caught. Nevertheless, the ring 4 is allowed to be displaced in the radial direction by the elastic deformation of the cylindrical elastic body 3, and the cylindrical elastic body 3 that supports the ring 4 has a high axial center CL and is hard. Since it becomes smaller and softer toward the outer side OUT, the pressing force at the axial center CL becomes stronger than the pressing force at the axial outer side OUT, so that the center part of the tread rubber T can be accurately pressed, and center deviation can be prevented. Furthermore, since a force acts outward from the center portion of the tread rubber T, air can be appropriately removed.
Second Embodiment
Hereinafter, a pressing roller according to a second embodiment of the present disclosure will be described with reference to the drawings.

  As shown in FIG. 3, the difference between the pressing roller 1 'of the second embodiment and the pressing roller 1 of the first embodiment is a ring 4' and a cylindrical elastic body 3 '. In the second embodiment, the hardness of the cylindrical elastic body 3 ′ is constant. On the other hand, the thickness of the cylindrical elastic body 3 ′ increases from the axial center CL toward the axially outer side OUT. As the thickness of the cylindrical elastic body 3 ′ changes, the inner diameter of the ring 4 ′ increases from the axial center CL toward the axially outer side OUT. The thickness change of the cylindrical elastic body 3 ′ may be performed for each ring, or may be stepwise with one or more rings as one step, as in the first embodiment.

  According to the above configuration, since the hardness of the cylindrical elastic body 3 ′ is constant, if the thickness of the cylindrical elastic body 3 ′ is large, the spring constant decreases, the pressing force becomes weak, and the pressing force of the axially outer side OUT is reduced. Becomes weaker than the axial center CL. On the contrary, if the cylindrical elastic body 3 ′ is thin, the spring constant increases, the pressing force becomes stronger, and the pressing force at the axial center CL becomes stronger than the axial outer side OUT. As a result, the pressing force against the central portion of the tread rubber can be increased compared to the outside in the width direction.

As described above, the presser roller 1 ′ of the second embodiment is
A presser roller 1 'that rolls along the circumferential direction while pressing the outer peripheral surface of the tread rubber T,
A shaft 2 held at both ends, a cylindrical elastic body 3 ′ covering the outer periphery of the shaft 2, a plurality of rings 4 ′ supported on the outer peripheral surface of the cylindrical elastic body 3 ′ and arranged in the axial direction AD; The plurality of rings 4 ′ have the same outer diameter, and the thickness of the cylindrical elastic body 3 ′ increases from the axial center CL toward the axial outer side OUT.

  Thus, the cylindrical elastic body 3 ′ has a weak pressing force when it is thick, and has a strong pressing force when it is thin. The pressing force at the axial center CL becomes stronger than the pressing force at the axially outer side OUT, so that the central portion of the tread rubber T can be accurately pressed, and center deviation can be prevented. Further, since a force acts outward from the central portion of the tread rubber T, air can be appropriately removed.

The manufacturing method of the tire constituent member of the second embodiment includes a step of molding the tread rubber T and a member to be disposed on the inner peripheral side of the tread rubber,
Disposing the tread rubber above the member;
A step of rolling the tread rubber along the circumferential direction while pressing the outer peripheral surface of the tread rubber with the presser roller 1 ′ described in the second embodiment, and pressing the tread rubber to the member.

  According to this method, as the cylindrical elastic body 3 ′ becomes thicker, the pressing force becomes weaker, and when it becomes thinner, the pressing force becomes stronger. The pressing force at the axial center CL becomes stronger than the pressing force at the axially outer side OUT, so that the central portion of the tread rubber T can be accurately pressed, and center deviation can be prevented. Further, since a force acts outward from the central portion of the tread rubber T, air can be appropriately removed.

  In addition, it is possible to employ | adopt the structure employ | adopted by said each embodiment as another arbitrary embodiment.

DESCRIPTION OF SYMBOLS 1, 1 '... Pressing roller 2 ... Shaft 3, 3' ... Cylindrical elastic body 4, 4 '... Ring CL ... Axis direction center OUT ... Axial direction outer side

Claims (6)

A presser roller that rolls along the circumferential direction while pressing the outer peripheral surface of the tread rubber,
A shaft held at both ends;
A cylindrical elastic body is a thick roast covering the outer periphery of the shaft is constant,
A plurality of rings supported on the outer peripheral surface of the cylindrical elastic body and arranged in the axial direction;
The plurality of rings have the same outer diameter,
The cylindrical elastic body has a presser roller whose hardness decreases from the center in the axial direction toward the outside in the axial direction.   2. The presser roller according to claim 1, wherein the cylindrical elastic body has at least three different hardnesses, and the hardness gradually decreases from the axial center to the axially outer side.   The presser roller according to claim 1 or 2, wherein the cylindrical elastic body has four different hardnesses, and the hardness gradually decreases from the axial center to the axially outer side.   The range of less than 17.5% of the width of the tread rubber from the axial center to the outer side in the axial direction of the cylindrical elastic body has a JISA hardness of 30 °, and a range of 17.5% or more and less than 32.5% has a JISA hardness. The press roller according to claim 3, wherein a range of 25 °, 32.5% or more and less than 42.5% has a JISA hardness of 20 °, and a range of 42.5% or more has a JISA hardness of 15 °.   2. The presser roller according to claim 1, wherein the cylindrical elastic body has a hardness that decreases for each ring from an axial center to an axially outer side. Forming a tread rubber and a member to be disposed on the inner peripheral side of the tread rubber;
Disposing the tread rubber above the member;
Preparation of claim 1 in the pressing roller according to any one of 5 to roll along the circumferential direction while pressing the outer peripheral surface of the tread rubber, comprising a step of bonding the tread rubber to said member, a tire component member Method.

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