JP2017065232A - Tire vulcanization mold, tire vulcanization device and manufacturing method of tire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tire vulcanization mold capable of forming a bent hole extending in a desired direction regardless of a formation position.SOLUTION: A tire vulcanization mold 10 has an upper-side side plate 12 molding a side wall part T2 of a green tire T, a negative pressure space S is arranged in a back face 10b of the upper-side side plate 12, a terminal part of the upper-side side plate 12 opens to a molding face 10a, and a first bent hole 35A of which a part locates in an outside of the negative pressure space S when viewing in an axial direction thereof from the molding surface 10a side and a second bent hole 35B communicating the first bent hole 35A and the negative pressure space S are provided.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a tire vulcanizing mold, a tire vulcanizing apparatus, and a tire manufacturing method.

  Conventionally, a tire vulcanization mold is provided with a plurality of vent holes on a molding surface for molding a tire surface, and the air interposed between the tire surface and the molding surface is vent holes when the tire is vulcanized. It is discharged through a negative pressure space provided on the back side of the mold. The negative pressure space communicates with an external negative pressure source, and is configured as a space sealed by a sealing means between a tire vulcanization mold and a container that accommodates the mold (for example, Patent Document 1). And 2).

  When the vent hole is formed as described above, unvulcanized rubber flows into the vent hole after the air is discharged, and a beard-like vent spew integrated with the vulcanized tire is formed. The vent spew is pulled out from the vent hole when the vulcanized tire is taken out and removed by a trimming process.

  Here, in order to omit the trimming step, a piece vent or a spring vent may be attached to the molding surface side of the vent hole. In that case, it is desirable to provide the vent hole so as to be perpendicular to the molding surface so that the tip portion on the molding surface side is along the tire surface.

JP 2010-201885 A JP-A-6-198764

  However, depending on the shape of the tire surface, it may be difficult to provide the vent hole perpendicular to the tire surface.

  For example, the portion on the inner diameter side in the tire radial direction from the maximum width position of the tire on the sidewall is inclined inward in the width direction as it proceeds toward the inner diameter side. It will incline toward the radially inner diameter side. In this case, the vent hole is opened outside the range of the negative pressure space on the back surface side of the tire vulcanization mold, more specifically, on the inner diameter side than the sealing means for sealing the radial inner diameter side of the negative pressure space. In some cases, the vent hole cannot be communicated with the negative pressure space in an airtight state, and air cannot be suitably discharged.

  Therefore, it is necessary to provide the vent hole so that the entire vent hole is located within the range of the negative pressure space when viewed in the axial direction from the molding surface side. Depending on the formation position, the vent hole is provided in a desired direction. You may not be able to.

  The present invention has been made in view of the above problems, and provides a tire vulcanization mold capable of forming a vent hole extending in a desired direction regardless of the formation position, and a tire manufacturing method using the mold. The purpose is to do.

  The present invention is a tire vulcanization mold that includes a side plate that molds a sidewall portion of a tire, and is provided with a negative pressure space on the back surface of the side plate, and one end portion of the side plate is molded. A first vent hole that is open to a surface, and at least a part of the first vent hole is located outside the negative pressure space when viewed in the axial direction from the molding surface side; and A second vent hole communicating with the negative pressure space is provided.

  According to the present invention, even when the first vent hole extends from the molding surface toward the outside of the range of the negative pressure space, the second vent hole communicates with the first vent hole and the negative pressure space. The molding surface and the negative pressure space can be communicated with each other. In other words, the first vent hole can be communicated with the negative pressure space through the second vent hole even when the first vent hole is provided so as to open at any position on the molding surface and extend in any direction. . That is, the vent hole can be formed to extend in a desired direction regardless of the formation position.

  The first vent hole extends perpendicularly to the molding surface, a vent plug is mounted on the molding surface side, and a sealing member that seals the first vent hole from the back side on the back surface side Is preferably mounted.

  In addition, the said vent plug should just be attached to a vent hole, and should suppress the production | generation of a vent spew, For example, a spring vent plug and a piece vent plug can be used.

  According to this configuration, for example, when a spring vent plug is attached, a vent spew does not occur, so the trimming process can be omitted, and a tire with excellent aesthetics that does not leave trimming marks is vulcanized. it can.

  Further, when the piece vent plug is attached, the vent spew is reduced in diameter, so that the trimming process can be omitted. Further, since the piece vent can be mounted perpendicular to the molding surface, it is not necessary to process the tip of the piece vent along the molding surface, and for example, it is possible to use a hard piece vent that is difficult to process.

  It is preferable that the seal member is constituted by a bolt including a seal member in a screw portion.

  According to this configuration, since the seal member can be easily attached and detached, the vent plug attached to the first vent hole can be easily removed by removing the seal member and pushing it out from the back side. Therefore, the vent plug can be easily cleaned and replaced, so that maintainability is good.

  The first vent hole may be formed as a stop hole that does not penetrate to the negative pressure space side.

  According to this aspect, it is possible to eliminate the need to attach the seal member to the back side by preventing the first vent hole from passing through the back side unnecessarily. In addition, by providing the first vent hole perpendicular to the molding surface, the moving direction of the mold at the time of mold release and the extending direction of the vent spew formed in the first vent hole can be matched. , Vent vent can be prevented.

  Further, the invention according to another aspect of the present invention provides a negative pressure space between a tire vulcanization mold having a side plate for molding a sidewall portion of a tire and the tire vulcanization mold accommodated inside. An end portion of the side plate that is open to the molding surface, and when viewed in the axial direction from the molding surface side, A first vent hole, which is located outside the negative pressure space, and a second vent hole that communicates the first vent hole and the negative pressure space are provided.

  Further, the invention according to still another aspect of the present invention provides a negative load between a tire vulcanization mold having a side plate for forming a sidewall portion of a tire and the tire vulcanization mold accommodated inside. A tire manufacturing method using a tire vulcanizing apparatus including a container for forming a pressure space, wherein when the tire is pressed against a molding surface of the side plate and vulcanized, the side plate One end of the air interposed between the molding surface and the sidewall portion is open to the molding surface, and when viewed from the axial direction from the molding surface side, outside the negative pressure space. The first vent hole, which is positioned, is discharged into the negative pressure space through a second vent hole that communicates the first vent hole and the negative pressure space.

  According to the tire vulcanization mold and the tire manufacturing method according to the present invention, the vent hole can be formed to extend in a desired direction regardless of the formation position.

1 is a front sectional view schematically showing a tire vulcanizing apparatus according to an embodiment of the present invention. The figure which expands and shows the periphery of the side plate of FIG. The figure which expands and shows the X section of FIG. The figure which shows notionally operation | movement of a tire vulcanizer. The figure similar to FIG. 2 which concerns on other embodiment.

  Embodiments according to the present invention will be described below with reference to the accompanying drawings. In addition, the following description is only illustrations essentially and does not intend restrict | limiting this invention, its application thing, or its use. The drawings are schematic, and the ratio of each dimension is different from the actual one.

  As schematically shown in FIG. 1, a tire vulcanizing apparatus 1 according to an embodiment of the present invention includes a tire vulcanization mold 10 for vulcanizing and molding a raw tire T into a predetermined shape, and the tire vulcanization mold. And a bladder 3 that bulges the raw tire T from the inner side and presses it against the molding surface 10a of the tire vulcanizing mold 10. In the tire vulcanization mold 10, the raw tire T is set with the tire axis line directed in the vertical direction.

  The tire vulcanizing mold 10 includes an annular tread ring 11 for forming the tread portion T1 of the raw tire T, and a pair of upper and lower side plates 12, 13 for forming the sidewall portion T2 of the raw tire T. And a pair of upper and lower bead rings 14 and 15 for forming the bead portion T3 of the green tire T.

  The tread ring 11 is divided into a plurality of (for example, seven) sectors 11 a in the tire circumferential direction, and each sector 11 a is provided so as to be able to be expanded and contracted in the tire radial direction when the tire vulcanizing mold 10 is opened and closed. . For example, the sectors 11a are radially spaced apart when the mold is open, and are in contact with each other when the mold is closed, so that an annular tread ring 11 is formed. That is, the tire vulcanization mold 10 is configured as a so-called segmented mold.

  The container 20 includes an outer peripheral container 21 that supports the tread ring 11 from the outer periphery, an upper container 22 that supports the upper side plate 12 from the upper surface, and a lower container 23 that supports the lower side plate 13 from the lower surface. ing. The outer peripheral container 21 has an annular tapered block 24 having a conical tapered surface 24a formed on the inner periphery, and a tapered surface 25a corresponding to the tapered surface 24a on the outer periphery, and each sector 11a is individually provided. And a plurality of sector blocks 25 divided so as to be held.

  Then, by lowering the upper container 22 together with the outer peripheral container 21, the upper side plate 12 moves toward the sidewall portion T2 of the raw tire T, and both the tapered surfaces 24a and 25a of the tapered block 24 and the sector block 25 are moved. By cooperation, each sector 11a moves toward the tread portion T1 of the raw tire T toward the inner diameter side in the tire radial direction. In this way, the mold closing operation of the tire vulcanizing mold 10 is performed. On the contrary, the mold opening operation of the tire vulcanizing mold 10 is performed by raising the outer peripheral container 21 and the upper side plate 22.

  Here, a plurality of vent holes 30 extending from the molding surface 10a side to the back surface 10b side are formed in the tire vulcanization mold 10. Further, a negative pressure space S is formed between the tire vulcanization mold 10 and the container 20, and when the raw tire T is vulcanized, the tire surface and the molding surface 10 a of the tire vulcanization mold 10 are formed. The intervening air is sucked into the negative pressure space S through the vent hole 30 and discharged. As a result, the occurrence of air accumulation when the raw tire T is vulcanized is suppressed.

  Here, the negative pressure space S is provided as a space between the back surface 10 b and the inner surface of the container 20 including a gas discharge groove 10 c (see FIG. 2) formed in the back surface 10 b of the tire vulcanizing mold 10. In each part of the tire vulcanizing mold 10 and the container 20, the O-ring 4 is appropriately sealed, and the tire vulcanizing mold 10 and the container 20 are connected to a negative pressure source (not shown).

  FIG. 2 shows the periphery of the upper side plate 12 in an enlarged manner. More specifically, in the sidewall portion T2 of the raw tire T, the sidewall located on the inner diameter side in the tire radial direction from the maximum width position T2max. The periphery of the inner diameter side portion T21 is shown. As shown in FIG. 2, each vent hole 30 is provided with an end portion 30 a that opens to the molding surface 10 a side so as to be substantially orthogonal to the molding surface 10 a, and vents are formed on the molding surface 10 a side. A plug 50 is attached.

  A plurality of gas discharge grooves 10c extending radially in the tire radial direction are formed on the back surface 10b of the upper side plate 12, and each vent hole 30 communicates with any one of the gas discharge grooves 10c. Further, the position of the opening on the back surface 12b side of the upper side plate 12 is set. In addition, although illustration is abbreviate | omitted, the several gas exhaust groove 10c extended in a tire peripheral direction is similarly formed in the back surface of each sector 11a.

  As shown in FIG. 3 in which the X part of FIG. 2 is enlarged, in the present embodiment, the vent plug 50 includes a cylindrical housing 51 fitted into the vent hole 30 and a passage inserted into the housing 51. This is a so-called spring vent plug provided with a stem 52 that opens and closes and a spring 53 that urges the stem 52 so as to protrude from the molding surface 10a.

  Referring to FIG. 2, the upper container 22 is provided with an O-ring 4 that seals the inner diameter side in the tire radial direction of the negative pressure space S provided between the upper side plate 12. Accordingly, a negative pressure space S is formed between the back surface 10 b of the upper side plate 12 and the lower surface 22 a of the upper container 22 on the outer side in the tire radial direction from the O-ring 4. The O-ring 4 is provided substantially corresponding to the position in the tire width direction of the bead portion T3 (see FIG. 1) of the raw tire T, and the inner diameter side in the tire radial direction on the back surface 10b side of the upper side plate 12. It is provided in the vicinity of the end portion.

  Here, the sidewall inner diameter side portion T21 of the raw tire T has a tire width direction dimension that decreases from the maximum width position T2max toward the tire radial direction inner diameter side. As the tire advances toward the inner diameter side in the tire radial direction, it is inclined inward in the tire width direction. For this reason, each vent hole 31-35 provided in the side wall inner diameter side portion 21 in a plane is inclined toward the inner diameter side in the tire radial direction from the molding surface 10a side toward the rear surface 10b side, and the opening in the rear surface 10b. The position is located on the inner diameter side in the tire radial direction.

  In particular, since the vent hole 35 provided in the rim protector portion T21a is located closest to the inner diameter side in the tire radial direction among the vent holes 31 to 35, the opening position in the back surface 10b is positioned closer to the inner diameter side in the tire radial direction. become. Specifically, at least a part of the vent hole 35 is positioned outside the negative pressure space S when the one end 30a side is viewed in the axial direction from the molding surface 10a side.

  In the present embodiment, the vent hole 35 is composed of a first vent hole 35A having one end opened to the molding surface 10a, and a second vent hole 35B communicating the first vent hole 35A and the negative pressure space S. ing.

  In the first vent hole 35A, a vent plug 50 is attached to one end portion that opens to the molding surface 10a, and the other end portion that opens to the back surface 10b is sealed by the seal member 5. Although various sealing means can be used for the seal member 5, in this embodiment, the seal member 5 is configured by a seal bolt in which a seal material is wound around a screw portion, and is detachable.

  The second vent hole 35B is provided so as to communicate the gas discharge groove 10c and the first vent hole 35A. More preferably, the second vent hole 35B extends from the end of the gas discharge groove 10c adjacent to the first vent hole 35A on the inner side in the tire radial direction, thereby shortening the path of the second vent hole 35B easily. It can be configured.

  In the tire vulcanizing apparatus 1 to which the tire vulcanizing mold 10 having the above configuration is mounted, the raw tire T is vulcanized and formed as follows.

  As shown in FIG. 4A, the green tire T is placed on the lower side plate 13 in the mold open state so that the axial direction of the green tire T is up and down. At this time, the bead portion T3 positioned on the lower side is positioned on the lower bead ring 15.

  Next, as shown in FIG. 4B, air is supplied into the bladder 3 to be inflated, and the inner side surface of the raw tire T is held by the outer peripheral surface thereof. As a result, the raw tire T is supported by the lower bead ring 15 and the bladder 3 and is not in contact with the lower side plate 13.

  Next, as shown in FIG. 4C, the outer peripheral container 21 and the upper container 23 are lowered by driving a driving device (not shown), and the mold closing operation is started. Accordingly, first, the upper bead ring 14 comes into contact with the bead portion T3 located on the upper side of the raw tire T. And the raw tire T deform | transforms via the bead part T3, and the upper side plate 12 contact | abuts to the raw tire T. FIG.

  Subsequently, as shown in FIG. 4D, the lowering operation of the upper container 22 is temporarily stopped at a predetermined position from when the upper side plate 12 contacts the raw tire T to the position where the mold closing is completed. Further, as shown in FIG. 4E, the raw tire T is sandwiched between the upper side plate 12 and the lower side plate 13 by lowering the upper container 22 to the mold closing completion position.

  Then, as shown in FIG. 4F, the lowering of the outer peripheral container 21 is continued even after the upper container 22 is lowered to the mold closing completion position, and the taper block 24 is moved downward. Then, the taper surface 24 a on the inner peripheral side of the taper block 24 presses the taper surface 25 a on the outer peripheral side of the sector block 25. Thereby, each sector 11a fixed to the segment block 25 moves to the tire radial inside diameter side. Thereby, the mold closing operation is completed.

  Thus, the raw tire T is pressed by the upper side plate 12, the lower side plate 13, and the sector 11a on the outer side and the bladder 13 on the inner side, and the mold closing operation is completed. In this state, the green tire T is vulcanized to complete the tire.

  At this time, the air interposed between the molding surface 10a of the tire vulcanizing mold 10 and the tire surface of the raw tire T is sucked into the negative pressure space S and discharged through the vent hole 30. It has become. Further, as shown in FIG. 2, the air interposed between the upper side plate 12 in the rim protector portion T21a of the raw tire T is negatively pressured via the first vent hole 35A and the second vent hole 35B. It is discharged into the space S.

  Further, since each vent hole 30 is provided so as to be substantially orthogonal to the molding surface 10a, the distal end portion 50a of the vent plug (spring vent plug) 50 is easily along the molding surface 10a, and after vulcanization molding. The tire surface is formed on a smooth surface that does not generate vent spew. Further, since no vent spew is generated, the trimming step can be omitted, and a tire having excellent aesthetic appearance without leaving trimming marks can be vulcanized.

  Since the rim protector portion T21a is formed so as to protrude in the tire width direction from the basic profile P of the sidewall portion T2, the rim protector portion of the upper side plate 12 particularly in the tire vulcanizing mold 10. Air easily collects in a portion corresponding to T21a. On the other hand, conventionally, when the vent hole 30 is formed in a plane corresponding to the rim protector portion T21a, the vent hole 30 opens outside the range of the negative pressure space S on the back surface 10b side as described above. For this reason, the vent plug 50 could not be mounted at a position corresponding to the rim protector portion T21a.

  However, in the present embodiment, the vent hole 35 corresponding to the rim protector portion T21a is configured by the first vent hole 35A and the second vent hole 35B, so that the first vent hole 35A is used to make the surface straight on the molding surface 10a side. The second vent hole 35B can communicate with the negative pressure space S on the back surface 10b side while further providing airtightness.

  That is, even when the first vent hole 35A extends from the molding surface 10a toward the outside of the negative pressure space S, the second vent hole 35B that connects the first vent hole 35A and the negative pressure space S is formed. The molding surface 10A and the negative pressure space S can be communicated with each other. In other words, the first vent hole 35A communicates with the negative pressure space S via the second vent hole 35B regardless of the position where the first vent hole 35A is opened at any position on the molding surface 10A and extends in any direction. Can be made. That is, the vent hole 30 can be formed to extend in a desired direction regardless of the formation position.

Moreover, the seal member 5 that seals the back surface 10b side of the first vent hole 35A is configured by a removable seal bolt. Thus, by removing the seal bolt, the vent plug 50 can be easily pushed out from the back surface 10b side of the first vent hole 30 ₅ A to the molding surface 10a side, whereby the vent plug 50 can be easily cleaned or replaced. Therefore, maintainability of the vent plug 50 is good.

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

  For example, in the above embodiment, a spring vent plug is used as the vent plug 50, but a piece vent plug may be used. As a result, the vent spew is reduced in diameter so that the trimming process can be omitted. Further, since the piece vent can be mounted perpendicular to the molding surface, it is not necessary to process the tip of the piece vent along the molding surface, and for example, it is possible to use a hard piece vent that is difficult to process.

  Further, as shown in FIG. 5, it is not necessary to attach the vent plug 50 to the vent hole 30. In this case, the vent hole 30 does not need to penetrate to the back surface 10b side so that the vent plug 50 can be pushed out from the back surface side, and may be formed as a stop hole. Accordingly, it is possible to prevent the first vent hole 35A from being unnecessarily passed through to the back surface 10b side, and to eliminate the need for mounting the seal member 5 on the back surface 10b side. Further, by providing the first vent hole 35A perpendicular to the molding surface 10a, the movement direction when the upper mold side plate 12 is released and the direction in which the vent spew formed in the first vent hole 35A extends. Therefore, it is possible to prevent the vent from being cut.

  Moreover, although the said embodiment demonstrated taking the case of the vent hole 30 provided in the upper mold | type side plate 12, it does not restrict to this. That is, the present invention can also be applied to the vent hole 30 provided in the tread ring 11 and the lower side plate 13, and when the opening on the back surface 10b side is located outside the range of the negative pressure space S, the back surface 10b side is sealed. What is necessary is just to form the 2nd vent hole connected with the negative pressure space S, sealing with the member 5. FIG.

DESCRIPTION OF SYMBOLS 1 Tire vulcanizer 3 Bladder 4 O-ring 5 Seal member 10 Tire vulcanization mold 11 Tread ring 11a Sector 12 Upper side plate 13 Lower side plate 14 Upper bead ring 15 Lower bead ring 20 Container 21 Outer container 22 Upper container 23 Lower container 30 Vent hole 35A 1st vent hole 35B 2nd vent hole 50 Vent plug T1 Tread part T2 Side wall part T3 Bead part

Claims (6)

A tire vulcanization mold provided with a side plate for molding a sidewall portion of a tire, and provided with a negative pressure space on the back surface of the side plate,
In the side plate,
A first vent hole whose one end is open to the molding surface, and at least a part of the first vent hole is located outside the negative pressure space when viewed in the axial direction from the molding surface side;
A tire vulcanization mold provided with a second vent hole that communicates the first vent hole and the negative pressure space. The first vent hole is
Extending perpendicular to the molding surface,
A vent plug is attached to the molding surface.
The tire vulcanization mold according to claim 1, wherein a seal member that seals the first vent hole from the back side is attached to the back side.   The tire vulcanization mold according to claim 2, wherein the seal member is configured by a bolt including a seal member in a screw portion.   The tire vulcanization mold according to claim 1, wherein the first vent hole is formed as a stop hole that does not penetrate to the negative pressure space side. A tire vulcanizing apparatus comprising: a tire vulcanization mold having a side plate for forming a sidewall portion of a tire; and a container that forms a negative pressure space between the tire vulcanization mold accommodated inside the tire vulcanization mold Because
In the side plate,
A first vent hole that is open to the molding surface, and located outside the negative pressure space when viewed from the axial direction from the molding surface side;
A tire vulcanizing apparatus provided with a second vent hole that communicates the first vent hole and the negative pressure space. A tire vulcanizing apparatus comprising: a tire vulcanization mold having a side plate for forming a sidewall portion of a tire; and a container that forms a negative pressure space between the tire vulcanization mold accommodated inside the tire vulcanization mold A method for manufacturing a tire using
When the tire is pressed against the molding surface of the side plate and vulcanized and molded, one end of the air that is interposed between the molding surface of the side plate and the sidewall portion opens into the molding surface. The second vent hole communicates with the negative pressure space from the first vent hole, which is located outside the negative pressure space when viewed from the axial direction from the molding surface side. A method for manufacturing a tire, wherein the tire is discharged into the negative pressure space through a vent hole.

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