JP6107249B2 - Tire vulcanizing bladder and bladder unit - Google Patents

Description

  TECHNICAL FIELD The present invention relates to a tire vulcanizing bladder and a bladder unit, and more particularly, a tire vulcanization capable of preventing a clamp member at a peripheral edge of a cylindrical bladder from being pulled out while being clamped. This relates to a bladder and a bladder unit.

  When manufacturing a pneumatic tire, a green tire is set in a mold, and then a tubular vulcanizing bladder is inflated inside the green tire for vulcanization. There are clamp portions at the peripheral edge portions of both ends of the vulcanization bladder, and the clamp portions are sandwiched between clamp members. When the vulcanizing bladder is inflated, a tensile force acts on the clamp portion, and in some cases, the clamp portion may come off from the clamp member.

  In order to prevent a problem that the clamp part comes off from the clamp member, conventionally, for example, a thick part thicker than the film thickness of the cylindrical main body part is provided in the clamp part. However, this thick portion is formed of only rubber, like the cylindrical main body. Therefore, if the tensile force acting on the clamp part is excessive, the clamp part is deformed and the clamp part comes off from the clamp member.

  Therefore, a structure has been proposed in which the clamp portion of the tire vulcanizing bladder is bent and clamped by a clamp member having a clamping gap of the same shape as the bent shape (see Patent Document 1). With this proposed structure, when the vulcanizing bladder is expanded, the tensile resistance of the clamp portion increases, so that the clamp portion is difficult to come off.

  However, since the clamp part is made of only rubber like the cylindrical main body part, deformation when an excessive tensile force acts on the clamp part cannot be avoided, and the clamp part cannot be detached from the clamp member. There was a limit to preventing it.

JP 2004-82393 A

  An object of the present invention is to provide a bladder for tire vulcanization and a bladder unit that can prevent a clamp member at a peripheral edge of a cylindrical bladder from coming off from a clamp member to be clamped.

In order to achieve the above object, a tire vulcanizing bladder according to the present invention is a tire vulcanizing bladder provided with clamp portions clamped by clamp members at the peripheral edge portions at both ends of a cylindrical main body portion. Further, an annular reinforcing member extending in the circumferential direction is embedded , and portions other than the reinforcing member are made of rubber .

  The bladder unit of the present invention includes the tire vulcanization bladder described above and a clamp member that clamps clamp portions at both ends of the cylindrical main body portion of the tire vulcanization bladder. The clamp member in which the reinforcing member is embedded is set to be equal to or larger than the minimum clamping gap of the clamp member, and the portion of the minimum clamping gap is closer to the cylindrical main body than the position in which the reinforcing member is embedded. The clamp portion is configured to be clamped.

  According to the tire vulcanizing bladder of the present invention, the clamp portion in which the annular reinforcing member is embedded is reinforced and hardly deformed. Therefore, even when the vulcanizing bladder expands and an excessive tensile force acts on the clamp portion, the deformation of the clamp portion is suppressed, which is advantageous in preventing a problem that the clamp member comes off.

  Further, since the clamping force by the clamp member is transmitted to the reinforcing member, it is advantageous for firmly clamping the clamp part, and is more advantageous for preventing the clamp part from coming off. In addition, even if an excessive tensile force acts on the clamp part, the rubber of the clamp part is hardly cut off due to the reinforcement by the reinforcing member.

  Since the bladder unit of the present invention includes the tire vulcanization bladder described above and the clamp members that clamp the clamp portions at both ends of the cylindrical main body of the tire vulcanization bladder, the bladder vulcanization unit described above is provided. The effect of bladder can be obtained.

  Further, the thickness of the reinforcing member is set to be equal to or larger than the minimum clamping gap of the clamp member that clamps the clamp portion in which the reinforcing member is embedded, and the minimum clamping gap is a position where the reinforcing member is embedded. Since the clamp part on the cylindrical body part side is clamped more than the above, even if an excessive tensile force acts on the clamp part and the clamp part tries to come off from the clamp member, the reinforcing member has a minimum gap between the clamp members. It is caught without being able to pass through. Therefore, it becomes more and more advantageous to prevent the clamp part from coming off.

  In the tire vulcanization bladder according to the present invention, the clamp portion in which the reinforcing member is embedded has a thick portion thicker than the thickness of the cylindrical main body portion, and the reinforcing member is embedded in the thick portion. It is also possible to have a configuration. According to this configuration, since the rigidity of the clamp portion is increased, it is advantageous for preventing the clamp portion from coming off.

  Further, the thick-walled portion has a shape protruding on both the inner peripheral side and the outer peripheral side of the cylindrical main body, and the reinforcing member is embedded in each protruding portion protruding on the inner peripheral side and the outer peripheral side. It is also possible to have a configuration. According to this configuration, when the vulcanizing bladder is expanded, the tensile resistance of the clamp portion increases, which is advantageous in preventing the clamp portion from coming off.

  A thickness of the clamp portion in which the reinforcing member is embedded may be set to the same thickness as the thickness of the cylindrical main body portion. According to this configuration, since it is possible to avoid an increase in the time for vulcanizing the tire vulcanization bladder, the productivity of the tire vulcanization bladder can be improved.

  The clamp portion in which the reinforcing member is embedded may have a bent shape that protrudes toward the inner peripheral side and the outer peripheral side of the cylindrical main body portion. According to this configuration, when the vulcanizing bladder is expanded, the tensile resistance of the clamp portion increases, which is advantageous in preventing the clamp portion from coming off.

  The reinforcing member may be formed of a metal wire. According to this configuration, the rigidity of the clamp portion in which the reinforcing member is embedded is significantly increased, which is advantageous for preventing the clamp portion from coming off.

It is explanatory drawing which illustrates embodiment of the bladder for tire vulcanization | cure of this invention and a bladder unit in a longitudinal cross-section. It is a longitudinal cross-sectional view which illustrates the vicinity of an upper clamp part and an upper clamp part. It is a longitudinal cross-sectional view which shows the modification of an upper clamp part and an upper clamp member. It is a longitudinal cross-sectional view which shows another modification of an upper clamp part and an upper clamp member. It is a longitudinal cross-sectional view which shows another modification of an upper clamp part and an upper clamp member.

  Hereinafter, a tire vulcanizing bladder and a bladder unit according to the present invention will be described based on the embodiments shown in the drawings.

  A tire vulcanizing bladder 1 of the present invention illustrated in FIG. 1 (hereinafter referred to as a bladder 1) is made of rubber made of butyl rubber or the like, and is formed in a cylindrical shape. The thickness Gb of the cylindrical main body 2 is substantially constant. The film thickness Gb varies depending on the size of the tire to be vulcanized, but is, for example, about 4 mm to 20 mm.

  The peripheral edge portions at both ends of the cylindrical main body 2 in the cylinder axis direction are an upper clamp portion 3a and a lower clamp portion 3b. An annular reinforcing member 6 extending in the circumferential direction is embedded in each of the upper clamp portion 3a and the lower clamp portion 3b.

  The reinforcing member 6 is a member having higher rigidity than the rubber forming the bladder 1, and for example, a metal wire such as a steel wire or a steel cord, a resin cord, or the like can be used. That is, in the bladder 1, only the reinforcing member 6 is made of non-rubber, and the other parts are made of rubber.

  The number of reinforcing members 6 embedded in each of the upper clamp part 3a and the lower clamp part 3b is not limited to one, and a plurality of reinforcing members 6 may be provided. Further, the reinforcing members 6 embedded in the upper clamp portion 3a and the lower clamp portion 3b can be the same number or different numbers. The thickness (outer diameter) of the reinforcing member 6 can be changed by the upper clamp part 3a and the lower clamp part 3b. That is, the upper clamp portion 3a and the lower clamp portion 3b can have different rigidity.

  The bladder 1 is attached to the central mechanism 7 of the vulcanizer with the cylinder axis direction being the vertical direction. Specifically, the upper clamp portion 3a and the lower clamp portion 3b of the bladder 1 are sandwiched from above and below by the disc-shaped upper clamp member 8a and the lower clamp member 8b attached to the center post of the center mechanism 7, respectively. . The gaps between the upper clamp member 8a and the lower clamp member 8b are formed in the same shape as the upper clamp portion 3a and the lower clamp member 3b, respectively. The center post of the center mechanism 7 is provided with an injection nozzle 9 for injecting a heat medium H such as steam (and a pressure medium) into the bladder 1.

  The bladder unit of the present invention includes the bladder 1, the upper clamp member 8a, and the lower clamp member 8b.

  When the heat medium H is injected into the bladder 1 from the injection port 9, the bladder 1 expands. Accordingly, a tensile force acts on the upper clamp part 3a and the lower clamp part 3b.

  In the bladder 1 according to the present invention, the upper clamp portion 3a and the lower clamp portion 3b in which the reinforcing member 6 is embedded are reinforced by the reinforcing member 6 to be highly rigid and difficult to be deformed. Therefore, even if the bladder 1 expands and an excessive tensile force acts on the upper clamp portion 3a and the lower clamp portion 3b, deformation of the upper clamp portion 3a and the lower clamp portion 3b is suppressed. Therefore, it is advantageous to prevent the upper clamp part 3a and the lower clamp part 3b from coming out of the upper clamp member 8a and the lower clamp member 8b, respectively.

  Further, the clamping force by the upper clamp member 8a and the lower clamp member 8b is transmitted to the reinforcing member 6 embedded in the upper clamp portion 3a and the lower clamp portion 3b, respectively. That is, the upper clamp member 8a and the lower clamp member 8b sandwich the reinforcement member 6 through rubber covering the reinforcement member 6, respectively. Thereby, since the upper clamp part 3a and the lower clamp part 3b can be clamped more firmly, it becomes more and more advantageous to prevent the disconnection.

  In addition, since the upper clamp part 3a and the lower clamp part 3b are reinforced by the reinforcing member 6, even if an excessive tensile force is applied, the rubber of the upper clamp part 3a and the lower clamp part 3b is hardly cut off. There is also a merit that

  For the reinforcing member 6, it is more preferable to use a metal wire material that is significantly higher in rigidity than rubber. Thereby, since the rigidity of the upper clamp part 3a and the lower clamp part 3b in which the reinforcing member 6 is embedded is significantly increased, it is advantageous for preventing the disconnection.

  The reinforcing member 6 is preferably embedded in both the upper clamp portion 3a and the lower clamp portion 3b, but either the upper clamp portion 3a or the lower clamp portion 3b may be easily removed. In such a case, the reinforcing member 6 can be embedded in only one clamp part that is easily removed. That is, in the present invention, the reinforcing member 6 is embedded in at least one of the upper clamp part 3a and the lower clamp part 3b.

  In FIG. 2 to FIG. 5 described below, the upper clamp portion 3a and the upper clamp member 8a are illustrated as representatives of both ends of the cylindrical main body portion 2.

  In the embodiment of the bladder 1 and the bladder unit illustrated in FIG. 2, the thickness of the reinforcing member 6 is set to be equal to or larger than the minimum holding clearance mc of the clamp member 8 a that holds the clamp portion 3 a in which the reinforcing member 6 is embedded. . A gap between the upper clamp members 8a is formed in the same shape as the upper clamp portion 3a.

  The portion of the minimum clamping gap mc of the upper clamp member 8a is configured to clamp the upper clamp portion 3a on the cylindrical main body 2 side than the position where the reinforcing member 6 is embedded. Thereby, even if an excessive tensile force acts on the upper clamp portion 3a and tries to come out from the upper clamp member 8a, the reinforcing member 6 is caught without being able to pass through the minimum clamping gap mc of the upper clamp member 8a. Therefore, it becomes more and more advantageous to prevent the upper clamp part 3a from coming off.

  Simply, the upper clamp portion 3a in which the reinforcing member 6 is embedded has a thick portion 4 thicker than the film thickness Gb of the cylindrical main body portion 2, and the reinforcing member 6 is embedded in the thick portion 4. You can also According to this configuration, the rigidity of the upper clamp portion 3a is higher than that of the configuration without the thick portion 4, so that it is advantageous to prevent the upper clamp portion 3a from coming off.

  As illustrated in FIG. 3, the thick portion 4 has a shape protruding on both the inner peripheral side and the outer peripheral side of the cylindrical main body 2, and the protruding portions 5 a and 5 b protruding on the inner peripheral side and the outer peripheral side. Alternatively, the reinforcing member 6 may be embedded. A gap between the upper clamp members 8a is formed in the same shape as the upper clamp portion 3a. According to this configuration, when the bladder 1 is inflated, the tensile resistance of the upper clamp portion 3a increases, which is advantageous in preventing the upper clamp portion 3a from coming off the upper clamp member 8a.

  Further, even if an excessive tensile force is applied to the upper clamp portion 3a, the respective reinforcing members 6 are pulled close to each other and interfere with each other. Therefore, even if the thickness of each reinforcing member 6 is less than the minimum clamping gap mc of the upper clamp member 8a, the upper clamp portion 3a is caught by the minimum clamping gap mc of the upper clamp member 8a, and it is increasingly increased to prevent the removal. Become advantageous.

  As illustrated in FIG. 4, the thickness of the upper clamp part 3 a in which the reinforcing member 6 is embedded may be set to the same thickness as the film thickness Gb of the cylindrical main body part 2. A gap between the upper clamp members 8a is formed in the same shape as the upper clamp portion 3a. According to this configuration, since the thickness of the bladder 1 is substantially the same in all the parts, the time for vulcanizing the bladder 1 is avoided and the productivity of the bladder 1 is improved.

  In this embodiment, the upper clamp part 3 a in which the reinforcing member 6 is embedded has a bent configuration that protrudes toward the inner peripheral side and the outer peripheral side of the cylindrical main body part 2. A gap between the upper clamp members 8a is formed in the same shape as the upper clamp portion 3a. According to this configuration, when the bladder 1 is inflated, the tensile resistance of the upper clamp portion 3a increases, which is advantageous in preventing the upper clamp portion 3a from coming off.

  The reinforcing member 6 can be embedded other than the bending point, but if the reinforcing member 6 is embedded in the bending point of the upper clamp part 3a as in this embodiment, the effect of preventing the upper clamp part 3a from coming off can be further expected.

  The embodiment illustrated in FIG. 5 is obtained by increasing the reinforcing member 6 embedded in the upper clamp portion 3a with respect to the embodiment of FIG. In this embodiment, each reinforcing member 6 is embedded in a separate bending point of the upper clamp portion 3a. In this embodiment, the effect of preventing the upper clamp portion 3a from coming off can be further expected.

  In the present invention, the above-described embodiments can be applied in appropriate combination.

  Only the upper and lower clamp parts and the upper and lower clamp members are different, and five types of bladder units (conventional examples 1 and 2 and examples 1 to 3) are created as shown in Table 1, and the clamp members of the clamp parts of each bladder are produced. The difficulty of falling out of was evaluated. In the evaluation method, nitrogen was gradually injected into the inside of the bladder to expand it, and the pressure when the clamp part was removed from the clamp member was measured. When the bladder burst without the clamp part coming out, the pressure when bursting was measured. In addition, the outer diameter of the reinforcement member of Examples 1-3 is substantially the same.

  From the results of Table 1, when the clamp part and the clamp member have the same shape, the clamp member is less likely to come out than in the first example, and the clamp members in the second and third examples are out of comparison with the second example. It has become difficult. Thereby, it turns out that it becomes difficult to remove | deviate from a clamp member by embedding a reinforcement member in a clamp part.

DESCRIPTION OF SYMBOLS 1 Bladder 2 Cylindrical main-body part 3a Upper clamp part 3b Lower clamp part 4 Thick part 5a, 5b Protrusion part 6 Reinforcement member 7 Center mechanism 8a Upper clamp member 8b Lower clamp member 9 Injection nozzle H Heat medium

Claims (7)

In the tire vulcanizing bladder provided with clamp portions sandwiched by clamp members at the peripheral edge portions at both ends of the cylindrical main body portion, an annular reinforcing member extending in the circumferential direction is embedded in at least one clamp portion , A tire vulcanizing bladder, wherein the portion other than the reinforcing member is made of rubber .   2. The tire adder according to claim 1, wherein the clamp portion in which the reinforcing member is embedded has a thick portion thicker than the thickness of the cylindrical main body portion, and the reinforcing member is embedded in the thick portion. Sulfur bladder.   The thick-walled portion has a shape protruding on both the inner peripheral side and the outer peripheral side of the cylindrical main body, and the reinforcing member is embedded in each protruding portion protruding on the inner peripheral side and the outer peripheral side. Item 3. A tire vulcanizing bladder according to Item 2.   The tire vulcanization bladder according to claim 1, wherein a thickness of a clamp portion in which the reinforcing member is embedded is set to be the same as a thickness of the cylindrical main body portion.   The tire vulcanization bladder according to any one of claims 1 to 4, wherein the clamp portion in which the reinforcing member is embedded has a bent shape that protrudes toward an inner peripheral side and an outer peripheral side of the cylindrical main body portion.   The bladder for tire vulcanization according to any one of claims 1 to 5, wherein the reinforcing member is formed of a metal wire. A bladder for tire vulcanization according to any one of claims 1 to 6, and a clamp member that clamps clamp portions at both ends of a cylindrical main body portion of the bladder for tire vulcanization, wherein the thickness of the reinforcing member is The clamp member in which the reinforcing member is embedded is set to be equal to or larger than the minimum clamping gap of the clamp member, and the portion of the minimum clamping gap is a clamp on the cylindrical main body side from the position where the reinforcing member is embedded. A bladder unit configured to hold the part.

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