JP2018034427A - Bladder for tire vulcanization and method for producing tire using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bladder for tire vulcanization capable of easily changing the gauge distribution and to provide a method for producing a tire using the same.SOLUTION: There is provided a bladder for tire vulcanization 10 used in a tire vulcanization process, which comprises a bladder body 11 having a cylindrical membrane part 11A and clamp parts 11B formed on both ends of the membrane part 11A and an annular cover member 12 which is independent from the bladder body 11 and is laminated on the outer peripheral surface of the membrane part 11A, wherein the cover member 12 is locally disposed in a region corresponding to one or both of a tire crown part and a tire side part. A green tire G is vulcanized using such a bladder for tire vulcanization 10.SELECTED DRAWING: Figure 2

Description

  TECHNICAL FIELD The present invention relates to a tire vulcanizing bladder used in a tire vulcanizing process and a tire manufacturing method using the same, and more particularly, a tire vulcanizing bladder capable of easily changing a gauge distribution and the same. The present invention relates to a tire manufacturing method using

  In the process of vulcanizing the pneumatic tire, the bladder is placed inside the green tire, and the bladder is filled with a heating and pressing medium, thereby pressing the green tire against the molding surface of the mold, A green tire is heated by a heating and pressurizing medium filled in the bladder.

  Such a tire vulcanizing bladder has a cylindrical film part and clamp parts formed at both ends of the film part, and usually the gauge (thickness) of the tire forming region of the film part is substantially constant. It has become. On the other hand, for the purpose of accurately vulcanizing a tire having a complicated shape (see, for example, Patent Document 1), for the purpose of suppressing tire defects during vulcanization (for example, Patent Document 2,). 3), or for the purpose of making the vulcanized state of the tire uniform (see, for example, Patent Document 4), changing the gauge distribution of the bladder along the tire width direction has been proposed.

  However, since the required gauge distribution of the bladder changes every time the tire type changes, it is necessary to manufacture a dedicated bladder for each tire type. Therefore, when the gauge distribution of the bladder is changed along the tire width direction as described above, there is a problem that the manufacturing efficiency of the tire vulcanization bladder is extremely poor.

JP-A-8-216154 Japanese Patent No. 4175450 Japanese Patent No. 4517625 JP 2005-238579 A

  An object of the present invention is to provide a tire vulcanization bladder that can easily change the gauge distribution and a tire manufacturing method using the bladder.

  In order to achieve the above object, a tire vulcanizing bladder according to the present invention is a tire vulcanizing bladder used in a tire vulcanizing process, and includes a cylindrical membrane portion and clamp portions formed at both ends of the membrane portion. And an annular cover member that is independent of the bladder body and is laminated on the outer peripheral surface of the film part, and the cover member is either one of the tire crown part and the tire side part or It is characterized by being locally arranged in a region corresponding to both.

  Further, the tire manufacturing method of the present invention for achieving the above object is a tire manufacturing method using the tire vulcanizing bladder, wherein a green tire is inserted into a mold, and the inside of the green tire is The tire vulcanization bladder comprising a bladder main body and the cover member is inserted, and the green tire is vulcanized in a state where a heating and pressurizing medium is filled in the tire vulcanization bladder. Is.

  In the present invention, the tire vulcanization bladder includes a bladder main body and a cover member, and the cover member is locally disposed in a region corresponding to one or both of the tire crown portion and the tire side portion. Therefore, the gauge distribution of the tire vulcanizing bladder can be easily changed based on the cover member.

  In addition, it is possible to use a conventional bladder as the bladder body, and it is only necessary to add a cover member to the bladder body, thereby improving the manufacturing efficiency of the tire vulcanization bladder and increasing its manufacturing cost. It can be minimized.

  In the present invention, it is preferable that the bladder main body and the cover member are bonded to each other. Thereby, the integrity between a bladder main body and a cover member is ensured, and a tire vulcanization process can be performed smoothly.

  Or it is preferable that the bladder for tire vulcanization of this invention is provided with the restraint member which restrains a bladder main body and a cover member mutually in a non-adhesion state. Thereby, the integrity between a bladder main body and a cover member is ensured, and a tire vulcanization process can be performed smoothly. As such a restraining member, a pair of hook-and-loop fasteners or a pair of mechanical fasteners may be used.

  Furthermore, the tire vulcanizing bladder of the present invention preferably includes a plurality of cover members, and the materials of these cover members are different from each other. By adding a plurality of cover members made of different materials to the bladder main body in this way, the bladder characteristics can be arbitrarily adjusted based on the cover member.

  When manufacturing a tire using the tire vulcanization bladder described above, a green tire is inserted into a mold, a tire vulcanization bladder including a bladder main body and a cover member is inserted inside the green tire, The green tire is vulcanized in a state where the inside of the tire vulcanization bladder is filled with a heating and pressurizing medium. As a result, the green tire can be vulcanized using a tire vulcanizing bladder in which the gauge distribution is changed along the tire width direction, and various effects based on the difference in gauge distribution can be enjoyed.

It is a meridian sectional view showing an example of a bladder for tire vulcanization to which the present invention is applied. 1 is a meridian cross-sectional view showing a tire vulcanizing bladder according to an embodiment of the present invention. 1 is a side view showing a tire vulcanizing bladder according to an embodiment of the present invention. It is meridian sectional drawing which shows the bladder for tire vulcanization | cure which consists of other embodiment of this invention. It is a side view which shows the bladder for tire vulcanization | cure which consists of other embodiment of this invention. It is meridian sectional drawing which shows the bladder for tire vulcanization | cure which consists of further another embodiment of this invention. It is meridian sectional drawing which shows the bladder for tire vulcanization | cure which consists of further another embodiment of this invention. It is a perspective view which shows the state which expand | deployed the tire vulcanization bladder which consists of further another embodiment of this invention.

  Hereinafter, the configuration of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 shows an example of a tire vulcanizing bladder to which the present invention is applied. In FIG. 1, a bladder 10 is used in a vulcanization process of a green tire G. The bladder 10 has a cylindrical shape, and is inserted coaxially inside the green tire G put into the mold 20. Then, the bladder 10 functions to press the green tire G against the molding surface of the mold 20 by inflating the bladder 10 inside the green tire G. In FIG. 1, the mold 20 includes a lower mold 21, an upper mold 22 and a sector 23. Further, the lower end portion of the bladder 10 is held between the lower mold 21 and the lower clamp ring 24, and the upper end portion of the bladder 10 is held between the upper clamp ring 25 and the auxiliary ring 26.

  2 and 3 show a tire vulcanizing bladder according to an embodiment of the present invention. As shown in FIGS. 2 and 3, the bladder 10 includes a bladder main body 11 having a cylindrical film portion 11 </ b> A and clamp portions 11 </ b> B formed at both ends of the film portion 11 </ b> A, and independent of the bladder main body 11. And an annular cover member 12 laminated on the outer peripheral surface of the film part 11A at a position away from the clamp part 11B. The clamp part 11B is formed thicker than the film part 11A. The cover member 12 is locally disposed in a region corresponding to the tire crown portion.

  When a tire is manufactured using the tire vulcanizing bladder 10 described above, a green tire G is inserted into the mold 20, and the tire vulcanization comprising a bladder body 11 and a cover member 12 inside the green tire G. The bladder 10 is inserted, and the green tire G is vulcanized while the tire vulcanizing bladder 10 is filled with a heating and pressing medium. Thereafter, the mold 20 is opened, the tire vulcanization bladder 10 is extracted from the inside of the vulcanized tire, and the tire is removed from the mold 20 to complete the tire vulcanization process.

  As described above, the tire vulcanizing bladder 10 includes the bladder main body 11 and the cover member 12, and the cover member 12 has a structure that is locally disposed in a region corresponding to the tire crown portion. The gauge distribution of the sulfur bladder 10 can be easily changed based on the cover member 12.

  In addition, a conventional bladder can be used as the bladder main body 11, and it is only necessary to add the cover member 12 to the bladder main body 11. Therefore, the manufacturing efficiency of the tire vulcanizing bladder 10 is improved. An increase in manufacturing cost can be minimized. That is, the bladder main body 11 may be a common component and only the small cover member 12 may be processed according to the target gauge.

  In the embodiment described above, for example, it is desirable that the initial inner diameter of the cover member 12 at an arbitrary position is set to be smaller than the initial outer diameter of the bladder main body 11 at a position corresponding to the initial position. For example, the initial inner diameter of the cover member 12 is preferably smaller than the initial outer diameter of the bladder body 11 at the axial center position of the bladder 10. By making the initial inner diameter at an arbitrary position of the cover member 12 smaller than the initial outer diameter at the corresponding position of the bladder main body 11, the integrity between the bladder main body 11 and the cover member 12 is ensured, and the tire vulcanizing step Can be performed smoothly. That is, even if the bladder main body 11 and the cover member 12 are not fixed to each other, it is difficult for positional deviation to occur between them.

  Further, it is desirable that the material of the bladder main body 11 and the cover member 12 is selected so that the permanent distortion of the cover member 12 is smaller than the permanent distortion of the bladder main body 11. By making the permanent distortion of the cover member 12 smaller than the permanent distortion of the bladder main body 11, even if the bladder main body 11 and the cover member 12 repeatedly contract, the integrity between the two can be ensured.

  The bladder body 11 and the cover member 12 may be bonded to each other. For example, the cover member 12 is made of a material having vulcanization adhesiveness with respect to the bladder main body 11, the cover member 12 is disposed at a predetermined position after the bladder main body 11 is manufactured, and reheating and pressurizing processing is performed. Thus, the cover member 12 can be bonded to the bladder main body 11. Such reheating and pressurizing treatment can be substituted by the first tire vulcanization. The bladder body 11 and the cover member 12 may be bonded to each other via an adhesive.

  4 and 5 show a tire vulcanizing bladder according to another embodiment of the present invention. 4 and 5, a bladder 10 includes a cylindrical bladder main body 11 and an annular cover that is laminated on the outer peripheral surface of the film portion 11A at a position that is independent from the bladder main body 11 and deviates from the clamp portion 11B. The cover member 12 is locally disposed in a region corresponding to the tire side portions on both sides. In this case, the bladder main body 11 and the cover member 12 need to be fixed to each other by some means.

  As described above, the tire vulcanizing bladder 10 includes the bladder main body 11 and the cover member 12, and the cover member 12 has a structure that is locally disposed in a region corresponding to the tire side portion. The gauge distribution of the sulfur bladder 10 can be easily changed based on the cover member 12. The cover member 11 can be locally disposed in a region corresponding to one or both of the tire crown portion and the tire side portion.

  FIG. 6 shows a tire vulcanizing bladder according to still another embodiment of the present invention. In FIG. 6, in addition to the bladder main body 11 and the cover member 12, the tire vulcanizing bladder 10 includes a restraining member 13 that restrains the bladder main body 11 and the cover member 12 in a non-bonded state. The restraining member 13 includes a pair of hook-and-loop fasteners 13A and 13B that can be engaged with each other. Thereby, the position shift between the bladder main body 11 and the cover member 12 can be prevented, and the integrity of both can be ensured. Moreover, since it is the restraint in the non-adhesion state by hook-and-loop fastener 13A, 13B, the bladder main body 11 and the cover member 12 can be isolate | separated as needed.

The pair of hook-and-loop fasteners 13 </ b> A and 13 </ b> B constituting the restraining member 13 can be installed at any location in the laminated region of the bladder main body 11 and the cover member 12. It is desirable that the hook-and-loop fasteners 13A and 13B have elasticity. The hook-and-loop fasteners 13 </ b> A and 13 </ b> B are desirably arranged so as to be scattered along the circumferential direction of the bladder main body 11. In particular, the area of each fastener 13A, 13B should be reduced, the number of fasteners 13A, 13B should be increased according to the required engagement force, and they should be separated so as not to prevent expansion and contraction of the bladder body 11 and the cover member 12. . For example, the area of each fastener 13A, 13B is preferably 100 mm ² or less.

  The fasteners 13A and 13B can be fixed to the surfaces of the bladder main body 11 and the cover member 12 by using an adhesive. However, the fasteners 13A and 13B should be fixed using a sewing member such as a suture thread or a locking member such as a staple. Is also possible. Moreover, it is also possible to fix the fasteners 13A and 13B to the surfaces of the bladder main body 11 and the cover member 12 by vulcanization adhesion.

  The configuration of the fasteners 13A and 13B is not particularly limited. For example, a fastener having a sheet-like base material and a plurality of engaging elements formed on one surface of the base material may be used. it can. Moreover, the shape of each engaging element is not specifically limited, For example, a hook-shaped or loop-shaped engaging element is employable.

  FIG. 7 shows a tire vulcanizing bladder according to still another embodiment of the present invention. In FIG. 5, the tire vulcanizing bladder 10 includes a restraining member 14 that restrains the bladder body 11 and the cover member 12 in a non-bonded state in addition to the bladder body 11 and the cover member 12. The restraining member 14 includes a pair of mechanical fasteners 14A and 14B that can be attached to and detached from each other. Thereby, the position shift between the bladder main body 11 and the cover member 12 can be prevented, and the integrity of both can be ensured. Moreover, since it is the restraint in the non-adhesion state by mechanical fasteners 14A and 14B, the bladder main body 11 and the cover member 12 can be isolate | separated as needed.

The pair of mechanical fasteners 14A and 14B constituting the restraining member 14 means a member having a mechanical connection structure that allows repeated coupling and separation. Typical examples include mechanical fasteners called hooks or snaps, and more specifically in the clothing industry, snap buttons, ring snaps, ring hooks, American snaps, American hooks, eyelet hooks, spring hooks, Or what is called a jumper hook. Also, mechanical fasteners 14A, 14B are coupled portions small area (e.g., preferably 1mm ² ~115mm ^2, more preferably 4mm ² ~90mm ²⁾ is a is a point-like fasteners.

  Although the mechanical fasteners 14A and 14B can be directly fixed to the surfaces of the bladder main body 11 and the cover member 12 using an adhesive, the mechanical fasteners 14A and 14B are attached to a base material such as a rubber sheet. 14B may be fixed, and the base material may be fixed to the surface of the bladder main body 11 and the cover member 12 using a sewing member such as a suture thread or a locking member such as a staple. Moreover, it is also possible to fix the base material provided with the mechanical fasteners 14A and 14B to the surfaces of the bladder main body 11 and the cover member 12 by vulcanization adhesion.

  FIG. 8 shows a tire vulcanizing bladder according to still another embodiment of the present invention. In FIG. 8, the tire vulcanizing bladder 10 is depicted so that the circumferential direction C is along a straight line for convenience. As shown in FIG. 8, a plurality of grooves 15 extending in the circumferential direction of the bladder are formed on the outer surface of the bladder body 11, and a plurality of protrusions extending in the circumferential direction of the bladder are formed on the inner surface of the cover member 12. Article 16 is formed. And in the state which laminated | stacked the cover member 12 on the outer side of the bladder main body 11, the protrusion 16 of the cover member 12 fits in the groove | channel 15 of the bladder main body 11. FIG. According to such a structure, the position shift between the bladder main body 11 and the cover member 12 can be prevented, and the integrity of both can be ensured.

  In the embodiment described above, when the tire vulcanizing bladder 10 includes a plurality of cover members 12, the materials of the cover members 12 may be different from each other. By adding a plurality of cover members 12 made of different materials to the bladder body 11 as described above, the bladder characteristics can be arbitrarily adjusted based on the cover member 12.

  For example, in a structure in which the cover member 12 is disposed in a region corresponding to both the tire crown portion and the tire side portion, the cover member 12 corresponding to the tire side portion is relatively soft, and the cover member corresponding to the tire crown portion is provided. By making 12 relatively hard, the tire vulcanization bladder 10 can easily swell in the tire width direction, and in particular, it is possible to prevent vulcanization failure of flat tires.

  Further, in the structure in which the cover member 12 is disposed in the region corresponding to both the tire crown portion and the tire side portion, the cover member 12 corresponding to the tire side portion is made of a material having a relatively low thermal conductivity (rubber with a small amount of carbon). Composition) and the cover member 12 corresponding to the tire crown portion is made of a material having a relatively high thermal conductivity (a rubber composition containing a large amount of carbon), thereby vulcanizing the thick tire tread portion. On the other hand, over-vulcanization of thin tire sidewall portions can be prevented.

DESCRIPTION OF SYMBOLS 10 Bladder 11 Bladder main body 11A Film | membrane part 11B Clamp part 12 Cover member 13,14 Restraint member 13A, 13B Hook fastener 14A, 14B Mechanical fastener 15 Groove 16 Projection

Claims (7)

  In a tire vulcanization bladder used in a tire vulcanization process, a bladder main body having a cylindrical membrane portion and clamp portions formed at both ends of the membrane portion, and the membrane independent from the bladder main body. An annular cover member laminated on the outer peripheral surface of the portion, and the cover member is locally disposed in a region corresponding to one or both of the tire crown portion and the tire side portion. Tire vulcanization bladder.   The tire vulcanizing bladder according to claim 1, wherein the bladder main body and the cover member are bonded to each other.   The tire vulcanizing bladder according to claim 1, further comprising a restraining member that restrains the bladder main body and the cover member from each other in a non-bonded state.   The tire vulcanizing bladder according to claim 3, wherein the restraining member is a pair of hook-and-loop fasteners.   The tire vulcanizing bladder according to claim 3, wherein the restraining member is a pair of mechanical fasteners.   The tire vulcanization bladder according to any one of claims 1 to 5, comprising a plurality of cover members, and the materials of the cover members are different from each other.   A tire manufacturing method using the tire vulcanizing bladder according to any one of claims 1 to 6, wherein a green tire is inserted into a mold, and the bladder main body and the cover member are placed inside the green tire. A tire manufacturing method, comprising: inserting the tire vulcanization bladder comprising: and vulcanizing the green tire in a state where the inside of the tire vulcanization bladder is filled with a heating and pressing medium.

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