JP7623564B2 - Tire vulcanizing apparatus and method - Google Patents

Description

The present invention relates to a tire vulcanization device and method, and more specifically to a tire vulcanization device and method that can reduce the temperature difference between the top and bottom of a vulcanization bladder during vulcanization, suppress variation in the degree of vulcanization in the vertical direction of the tire during vulcanization, and is easy to maintain.

A method is known in which a vulcanization bladder inserted in a green tire in a closed vulcanization mold is inflated by injecting steam (heating medium) and nitrogen gas (pressurizing medium) through an inlet formed in a central mechanism, thereby vulcanizing the green tire to manufacture a tire. In this vulcanization method using steam and nitrogen gas, the specific gravity of nitrogen gas is greater than that of steam, so that steam is compressed at the top of the expanded vulcanization bladder and nitrogen gas is present below it. In addition, steam is condensed and accumulates at the bottom as a drain. Therefore, in the vulcanization bladder during vulcanization , the temperature at the top is higher than that at the bottom, resulting in a temperature difference between the top and bottom. Due to this, in the vulcanized tire, the degree of vulcanization varies in the vertical direction of the tire during vulcanization.

To solve these problems, various vulcanization methods and vulcanization devices have been proposed (see, for example, Patent Document 1). Conventionally, for example, it has been proposed to specify the direction of injection of steam or nitrogen gas, or to devise the timing of injection of steam or nitrogen gas. This aims to suppress the temperature difference between the top and bottom of the vulcanization bladder by stirring the mixture of steam and nitrogen gas inside the vulcanization bladder and homogenizing the internal temperature.

However, since the inside of the vulcanization bladder is already at a fairly high pressure, it is difficult to sufficiently stir the inside of the vulcanization bladder using the force of the injected steam or nitrogen gas. To achieve sufficient stirring, the injection pressure must be significantly increased. Therefore, there is room for improvement in reducing the temperature difference between the top and bottom of the vulcanization bladder during vulcanization and suppressing the variation in the degree of vulcanization in the vertical direction of the tire during vulcanization. Also, in order for the injection port (injection path) to function properly, it must be cleaned at appropriate times to prevent clogging, so there is also a need to improve maintainability.

Japanese Patent Application Publication No. 8-80530

The object of the present invention is to provide a tire vulcanization device and method that can reduce the temperature difference between the top and bottom of the vulcanization bladder during vulcanization, suppress the variation in the degree of vulcanization in the vertical direction of the tire during vulcanization, and is easy to maintain.

In order to achieve the above object, the tire vulcanization apparatus of the present invention comprises a central mechanism having a cylindrical vulcanization bladder inserted vertically therethrough, a vulcanization mold disposed so as to surround the central mechanism, an opening/closing means for opening and closing the vulcanization mold, a supply source for supplying a heating medium and a pressurizing medium to the inside of the vulcanization bladder, and an injection path extending vertically through the central mechanism to communicate the supply source with the inside of the vulcanization bladder, and the upper and lower opening edges of the vulcanization bladder are held by disk-shaped clamp parts attached vertically at intervals to the central mechanism, and the supply medium is injected through the injection path from an injection port located inside the vulcanization bladder. In a tire vulcanizing apparatus in which the heated medium and the pressurized medium are injected into the inside of the vulcanizing bladder, each of the clamping sections is constructed by stacking vertically divisible divided bodies, and the vertical spacing between each of the divided bodies constituting each of the clamping sections in each of the clamping sections communicates with the injection path to form a part of the injection path and the injection inlet, and the injection inlet is arranged continuously or intermittently around the entire circumferential end position of each of the clamping sections, and the injection inlet is located outer than the outer circumferential end of the opening edge held by each of the clamping sections.

The tire vulcanization method of the present invention includes inserting a green tire into a cylindrical vulcanization bladder having upper and lower opening edge portions respectively held by disk-shaped clamp portions attached at intervals above and below a central mechanism, arranging the green tire in a horizontal position in the vulcanization mold installed so as to surround the central mechanism with the vulcanization mold opened, and then closing the vulcanization mold and injecting a heating medium and a pressurizing medium supplied from a supply source through an injection passage extending above and below the central mechanism into the vulcanization bladder from an injection port of the injection passage located inside the vulcanization bladder, thereby In a tire vulcanization method in which a vulcanization bladder is inflated to vulcanize the green tire, each of the clamp portions is constructed by stacking vertically divisible segments, the vertical gaps between the segments constituting each of the clamp portions are connected to the injection passage and utilized as part of the injection passage and the injection inlet, and the injection inlet is disposed continuously or intermittently around the entire circumferential edge position of each of the clamp portions, and is positioned outer than the outer circumferential edge of the opening edge held by each of the clamp portions.

According to the present invention, the vertical spacing between the divided bodies is used as part of the injection path for injecting the heating medium and the pressurizing medium into the vulcanizing bladder. The injection ports of the injection paths are arranged continuously or intermittently around the entire circumference at the outer circumferential end positions of the clamping parts, and are positioned on the outer circumferential side of the outer circumferential end of the opening edge of the vulcanizing bladder. That is, the injection ports are arranged at a closer distance to the cylindrical peripheral surface of the vulcanizing bladder evenly in the circumferential direction than in the conventional method. As a result, even if the inside of the vulcanizing bladder is in a high-pressure state, the injected heating medium and pressurizing medium can easily flow along the inner surface of the vulcanizing bladder. As a result, the temperature difference between the top and bottom of the vulcanizing bladder during vulcanization is reduced, which is advantageous in suppressing the variation in the degree of vulcanization in the vertical direction of the tire during vulcanization.

In addition, the stacked divided bodies of each clamp section can be separated into upper and lower parts. Therefore, the injection passages of each clamp section can be easily cleaned by separating the divided bodies into upper and lower parts, greatly improving the maintainability of the injection passages and injection ports.

FIG. 2 is an explanatory diagram illustrating the left half of the tire vulcanization apparatus of the present invention in a vertical cross-sectional view with the vulcanization mold in a closed state. 2 is an explanatory diagram illustrating a segment, a sector mold, and a lower clamp portion of FIG. 1 in a plan view. FIG. 2 is an explanatory diagram illustrating an enlarged view of the periphery of a lower clamp portion in FIG. 1 ; 4 is an explanatory diagram illustrating the clamp portion of FIG. 3 in a plan view. FIG. 5 is an explanatory diagram illustrating the structure of the clamp portion of FIG. 4 in a vertical cross-sectional view. FIG. 2 is an explanatory diagram illustrating an upper clamp portion of FIG. 1 in a plan view; FIG. 13 is an explanatory diagram showing a modified example of the lower clamp portion in a plan view. FIG. 8 is an explanatory diagram illustrating the structure of the clamp portion of FIG. 7 in a vertical cross-sectional view. FIG. FIG. 13 is an explanatory diagram showing another modified example of the lower clamp portion in a plan view. 10 is an explanatory diagram illustrating the structure of the clamp portion of FIG. 9 in a vertical cross-sectional view. FIG. FIG. 13 is an explanatory diagram showing still another modified example of the lower clamp portion in a plan view. 12 is an explanatory diagram illustrating the structure of the clamp portion of FIG. 11 in a vertical cross-sectional view. FIG. 2 is an explanatory diagram illustrating the tire vulcanization apparatus in a state in which the vulcanization mold in FIG. 1 is opened and a heating medium is injected into the inside of the vulcanization bladder. FIG. 15 is an explanatory diagram illustrating the segment, sector mold, and lower clamp portion of FIG. 14 in a plan view. FIG. 14 is an explanatory diagram illustrating the tire vulcanization apparatus in a state in which a pressurized medium is being injected into the vulcanization bladder of FIG. 13. FIG. 16 is an explanatory diagram illustrating a state in which the vulcanization mold is opened after the green tire of FIG. 15 is vulcanized.

The tire vulcanization apparatus and method of the present invention will be described below based on the embodiment shown in the figures.

The tire vulcanizing device 1 (hereinafter referred to as the vulcanizing device 1) of the present invention illustrated in Figures 1 to 3 includes a central mechanism 3 equipped with a vulcanizing bladder 6 (hereinafter referred to as the bladder 6), a vulcanizing mold 9 (hereinafter referred to as the mold 9) installed so as to surround the central mechanism 3, an opening/closing means (vertical movement plate section 2 and container ring 15) for opening and closing the mold 9, a pressurized medium supply source 11A, and a heated medium supply source 11B. The central mechanism 3 includes injection paths 4A, 4B extending vertically to connect the respective supply sources 11A, 11B to the inside of the bladder 6.

The vulcanizing device 1 further includes a discharge passage 5 that extends vertically through the central mechanism 3, an upper plate 12 to which the mold 9 is attached, a lower plate 13, and a segment 14. The dashed line CL in the figure indicates the axial position of the central mechanism 3 (central post 3a). Although the left half of the vulcanizing device 1 is shown in Figure 1, the right half has substantially the same structure as the left half.

The mold 9 is a sectional type, and has an annular upper side mold 9A, an annular lower side mold 9B, and multiple sector molds 9C that are arc-shaped in plan view. The upper side mold 9A is attached to the underside of the upper plate 12. The upper plate 12 and the upper side mold 9A move up and down independently of the vertically movable plate section 2 and the contouring 15.

The lower side mold 9B is fixedly attached to the upper surface of the lower plate 13 fixed to the base. Each sector mold 9C is attached to the inner peripheral surface of the corresponding segment 14.

An upper bead ring 10 is attached to the inner circumferential lower surface of the upper side mold 9A. A lower bead ring 10 is attached to the inner circumferential upper surface of the lower side mold 9B.

Each sector mold 9C (segment 14) is arranged in an annular shape around the central mechanism 3. That is, as shown in FIG. 2, each sector mold 9C (segment 14) is arranged in an annular shape in a plan view, and the center of the annular shape is the dashed line CL. This annular center CL is the annular center of the upper side mold 9A and the lower side mold 9B.

The outer peripheral surface of each segment 14 is inclined from top to bottom toward the outer periphery. Each segment 14 has a guide groove extending in the vertical direction along its outer peripheral inclined surface.

A cylindrical container ring 15 is installed on the underside of the vertically moving plate section 2, which moves up and down above the central mechanism 3. The container ring 15 is positioned around the central mechanism 3 (annular center CL) and moves up and down on the outer periphery of each segment 14. The inner periphery of the container ring 15 is inclined from above toward the outer periphery. This inner periphery inclined surface of the container ring 15 and the outer periphery inclined surface of each segment 14 are positioned so as to face each other.

Multiple guide keys are arranged at intervals in the circumferential direction on the inner sloping surface of the container ring 15. These guide keys extend in the vertical direction along the inner sloping surface of the container ring 15. Each guide key engages with a guide groove of the corresponding segment 14, and the guide key (inner sloping surface of the container ring 15) and the guide groove (outer sloping surface of each segment 14) are configured to slide against each other.

The central mechanism 3 has a central post 3a, disk-shaped clamping parts 7A and 7B attached to the central post 3a at a distance above and below, and a bladder 6 held by the respective clamping parts 7A and 7B. The upper and lower opening edges 6a of the cylindrical bladder 6 are held by the upper and lower clamping parts 7A and 7B, respectively. More specifically, the upper opening edge 6a is held by being sandwiched between the upper clamping part 7A and the upper bead ring 10. The lower opening edge 6a is held by being sandwiched between the lower clamping part 7B and the lower bead ring 10.

One of the injection passages 4A extends vertically through the central post 3a, and extends from the upper end of the central post 3a toward the upper clamp portion 7A. The injection passage 4A terminates at the outer circumferential end of the upper clamp portion 7A, and an injection port 4h is disposed at the outer circumferential end of the clamp portion 7A. This injection port 4h is continuous around the entire circumferential direction of the clamp portion 7A. Furthermore, the injection port 4h is located on the outer circumferential side of the outer circumferential end 6b of the opening edge portion 6a held by the clamp portion 7A. This injection port 4h can also be disposed intermittently in the circumferential direction of the clamp portion 7A, as described below.

The other injection passage 4B extends vertically through the center post 3a and extends toward the lower clamp portion 7B at the longitudinal center of the center post 3a. The injection passage 4B terminates at the outer peripheral end of the lower clamp portion 7B, and an injection port 4h is disposed at the outer peripheral end of the clamp portion 7B. This injection port 4h is continuous around the entire circumferential direction of the clamp portion 7B. Furthermore, the injection port 4h is located on the outer peripheral side of the outer peripheral end 6b of the opening edge portion 6a held by the clamp portion 7B. This injection port 4h can also be disposed intermittently in the circumferential direction of the clamp portion 7B, as described below.

The exhaust passage 5 extends vertically through the central post 3a and terminates at the longitudinal center of the central post 3a, where an exhaust port 5h is located. An opening/closing valve is provided at the lower end of the exhaust passage 5, and opening the opening opens the lower end of the exhaust passage 5 to the outside air.

The lower ends of the injection paths 4A and 4B are each provided with an on-off valve, and the respective lower ends are connected to the pressurized medium supply source 11A and the heating medium supply source 11B. Therefore, the pressurized medium supply source 11A and the inside of the bladder 6 can communicate with each other through the injection path 4A. Also, the heating medium supply source 11B and the inside of the bladder 6 can communicate with each other through the injection path 4B. The pressurized medium supply source 11A supplies an inert gas such as nitrogen gas as the pressurized medium Mp. The heating medium supply source 11B supplies steam as the heating medium Mh.

Each of the clamping parts 7A and 7B is constructed by stacking vertically divisible parts V1 and V2. The basic structure of each of the clamping parts 7A and 7B is almost the same, so the structure will be explained using the lower clamping part 7B as an example.

As shown in Figures 3 to 5, the clamping section 7B is constructed by stacking the segments V1 and V2 one above the other and connecting them with a fixing member f such as a bolt. A gap is formed between the top and bottom of each of the segments V1 and V2. This gap is connected to the injection passage 4B. In other words, the vertical gap between the segments V1 and V2 is connected to the injection passage 4B and forms part of the injection passage 4B. Similarly, the vertical gap between the segments V1 and V2 of the upper clamping section 7A is connected to the injection passage 4A and forms part of the injection passage 4A.

In this embodiment, the injection port 4h is formed continuously around the entire circumference of the outer peripheral end face of the clamp portion 7B. And, since only the fixing member f exists in the vertical space between the divided bodies V1 and V2, the injection passage 4B formed in the clamp portion 7B is a wide flow passage that is annular in plan view, as shown in FIG. 4.

The divided bodies V1 and V2 can be stacked without being connected to each other using the fixing member f, for example, by simply engaging and fixing the center of each divided body V1 and V2 in a plan view to the central mechanism 3 (center post 3a). With this structure, there is essentially nothing between the vertical gap between the divided bodies V1 and V2.

As described below, the heating medium Mh is supplied through the injection passage 4B extending vertically and is sent into the injection passage 4B formed in the clamping portion 7B. Then, as shown in FIG. 4, the heating medium Mh is injected into the inside of the bladder 6 from the injection port 4h that is continuous around the entire circumferential edge of the clamping portion 7B.

Similarly, the pressurized medium Mp is supplied through the injection passage 4A extending vertically and is sent into the injection passage 4A formed in the clamping portion 7A. Then, as shown in FIG. 6, the pressurized medium Mp is injected into the inside of the bladder 6 from the injection port 4h that is continuous around the entire circumference of the outer periphery of the clamping portion 7A.

As shown in Figures 7 and 8, at least one of the divided bodies V1 (V2) can be designed to have a protrusion 8 protruding from the surface facing the other divided body V2 (V1) to be stacked. Protrusions 8 can also be provided on both divided bodies V1, V2. Protrusions 8 can also be provided only on one of the divided bodies V1 (V2), and the surface of the other divided body V2 (V1) facing the one divided body V1 (V2) can be made flat. In this embodiment, the top surface of the lower divided body V2 is flat.

The protrusions 8 define the injection passages 4B in the clamp portion 7B. In this embodiment, four linear protrusions 8 extend radially from the center of the clamp portion 7B in a plan view. As a result, the injection passages 4B in the clamp portion 7B extend radially from the center in a plan view. Four injection ports 4h are intermittently formed around the entire circumference of the outer peripheral end face of the clamp portion 7B. Each of the four branched injection passages 4B is formed in a fan shape, gradually widening toward the injection port 4h. The number of protrusions 8 is not limited to four, and for example, two to ten protrusions 8 may extend radially from the center of the clamp portion 7B in a plan view.

As shown in Figs. 9 and 10, multiple protrusions 8 having a substantially triangular shape in plan view can be arranged. As a result, the injection passages 4B in the clamp portion 7B extend radially from the center in plan view. Multiple injection ports 4h are intermittently formed around the entire circumference of the outer peripheral end face of the clamp portion 7B. Each of the multiple branched injection passages 4B gradually tapers toward the injection port 4h.

As shown in Figs. 11 and 12, multiple protrusions 8 that are arc-shaped in plan view can also be arranged. As a result, the injection paths 4B in the clamping portion 7B extend radially from the center in plan view. Multiple injection ports 4h are intermittently formed around the entire circumference of the outer peripheral end face of the clamping portion 7B. Each of the multiple branched injection paths 4B curves in the same direction toward the injection ports 4h.

The upper clamp portion 7A can also be provided with the protrusions 8 of the various specifications described above.

Next, we will explain an example of the procedure for vulcanizing a green tire G using this vulcanizing device 1 to manufacture a pneumatic tire T.

When vulcanizing the green tire G, the mold 9 is opened wide and the green tire G is placed sideways on the lower side mold 9B. The lower bead core of the green tire G is placed on the lower bead ring 10. The vulcanization bladder 6 is slightly inflated to hold the green tire G.

Next, as shown in FIG. 1, the upper side mold 9A is moved downward together with the upper plate 12, which is in the upper standby position, and the container ring 15 and each segment 14 are moved downward together with the vertically movable plate section 2. As a result, each segment 14 is placed on the upper surface of the lower plate 13, and each segment 14 is sandwiched between the upper and lower plates 12 and 13. In this state, each sector mold 9C (segment 14) is positioned in an expanded diameter position in a plan view, as shown in FIG. 2.

Next, the container ring 15 is moved further downward together with the vertically movable plate section 2 from the state shown in FIG. 1 to the state shown in FIG. 13. This causes the outer peripheral inclined surface of each segment 14 to be pressed by the inner peripheral inclined surface of the container ring 15 moving downward. As a result, as shown in FIG. 14, each sector mold 9C moves closer to the annular center CL, and these sector molds 9C are assembled into an annular shape to close the mold 9.

After the mold 9 is closed, the heating medium (steam) Mh supplied from the heating medium supply source 11B is injected through the injection path 4B and into the inside of the bladder 6 from the injection port 4h of the lower clamp portion 7B to further expand the bladder 6. Compared to the conventional method, the injection ports 4h are arranged evenly in the circumferential direction and at a closer distance to the cylindrical peripheral surface of the bladder 6. Therefore, the injected steam Mh flows upward along the inner surface of the bladder 6, so that the bladder 6 can be heated to the specified temperature in a shorter time. The steam Mh can be injected horizontally, diagonally upward, or diagonally downward.

After that, as shown in FIG. 15, the pressurized medium (nitrogen gas) Mp supplied from the pressurized medium supply source 11A is injected into the inside of the bladder 6 from the injection port 4h of the upper clamp portion 7A through the injection path 4A. The injected nitrogen gas Mp has a higher specific gravity than steam Mh. Compared to the conventional method, the injection ports 4h are arranged evenly in the circumferential direction and at a closer distance to the cylindrical peripheral surface of the bladder 6. Therefore, the injected nitrogen gas Mp flows downward along the inner surface of the bladder 6 without the injection pressure being significantly higher than the internal pressure of the bladder 6. The flow of the nitrogen gas Mp moderately stirs the mixed gas (M1, M2) inside the bladder 6, so that the temperature difference between the top and bottom of the bladder 6 during vulcanization is reduced. The nitrogen gas Mp can be injected horizontally, obliquely upward, or obliquely downward.

The green tire G is pressed against the inner surface of the mold 9 by the bladder 6, which is sufficiently heated and expanded by the injection of steam Mh and nitrogen gas Mp, and vulcanized. After the specified vulcanization time has elapsed and vulcanization is completed, the tire T is manufactured.

After the vulcanization of the green tire G is completed, the mixed gas (M1, M2) inside the bladder 6 is discharged from the discharge port 5h through the discharge path 5 to the outside, and the bladder 6 is contracted to separate the inner surface of the tire T from the outer surface of the bladder 6. In this embodiment, the upper surface of the lower clamp portion 7B is inclined downward toward the center. Therefore, the mixed gas (M1, M2) and drainage can be easily collected at the discharge port 5h below the inclined surface.

After that, as shown in FIG. 16, the upper movable plate portion 2 and the container ring 15 are moved upward to open the mold 9. Then, the tire T is removed from the open mold 9.

As described above, the vertical spacing between the divided bodies V1, V2 of the clamping parts 7A, 7B is used as part of the injection paths 4A, 4B for injecting the heating medium Mh and the pressurized medium Mp into the interior of the bladder 6. The injection ports 4h are arranged continuously or intermittently around the entire circumference at the outer circumferential end positions of the clamping parts 7A, 7B, and are positioned on the outer circumferential side of the outer circumferential end 6b of the opening edge part 6a of the bladder 6. In other words, the injection ports 4h are arranged evenly around the circumferential direction of the cylindrical peripheral surface of the bladder 6 and are arranged at a closer distance than in the conventional case.

Therefore, even if the inside of the bladder 6 is in a high-pressure state, the injected heating medium Mh and pressurizing medium Mp can be easily caused to flow along the inner surface of the bladder 6. As a result, the temperature difference between the top and bottom of the bladder 6 during vulcanization can be reduced, which is advantageous in suppressing the variation in the degree of vulcanization in the vertical direction of the tire during vulcanization. As a result, tire quality is improved.

In addition, each clamp section 7A, 7B can separate the stacked divided bodies V1, V2 into upper and lower parts. Therefore, the injection channels 4A, 4B in each clamp section 7A, 7B can be easily cleaned by dividing the divided bodies V1, V2 into upper and lower parts. This significantly improves the maintainability of the injection channels 4A, 4B and injection port 4h in the clamp sections 7A, 7B. In particular, as shown in Figures 9 and 11, work efficiency is significantly improved when cleaning the injection channels 4A, 4B which branch out into many parts.

The heating medium Mh can also be injected into the interior of the bladder 6 through the inlets 4h of both clamping parts 7A and 7B. Similarly, the pressurized medium Mp can also be injected into the interior of the bladder 6 through the inlets 4h of both clamping parts 7A and 7B.

As shown in Figs. 4 and 6, in a specification in which the injection port 4h is formed continuously around the entire circumference on the outer end surface of the clamping parts 7A and 7B, the heating medium Mh and the pressurizing medium Mp are injected from the entire circumference of the outer end of the clamping parts 7A and 7B. This makes it easier to suppress the temperature difference around the circumference of the bladder 6. As shown in Fig. 7, the same effect can be obtained when the injection port 4h is formed continuously around almost the entire circumference on the outer end surface of each of the clamping parts 7A and 7B.

As shown in FIG. 9, when the injection paths 4A and 4B extend radially from the center of the clamping portions 7A and 7B and gradually taper toward the injection port 4h, the injection speed at the injection port 4h is faster for the same injection pressure. This makes it possible to further increase the fluidity of the injected heating medium Mh and pressurized medium Mp inside the bladder 6.

As shown in FIG. 11, when the injection paths 4A, 4B extend radially from the center of the clamping portions 7A, 7B and curve in the same direction toward the injection port 4h, the injected heating medium Mh and pressurized medium Mp tend to generate a swirling flow inside the bladder 6. This is expected to improve the stirring effect of the mixed gas (M1, M2) inside the bladder 6.

The shapes of the injection passages 4A, 4B in the clamping parts 7A, 7B vary depending on the tire specifications, allowing optimal vulcanization. Therefore, it is advisable to prepare multiple sets P of divided bodies V1, V2 in which the injection passages 4A, 4B in the clamping parts 7A, 7B have different shapes in plan view for one vulcanizing device 1. Then, depending on the specifications of the green tire G to be vulcanized by the vulcanizing device 1, one set P can be selected from the multiple sets P and attached to the central mechanism 3 for use.

For example, if one of the divided bodies V1 (V2) does not have the protrusion 8, then simply replacing the other divided body V2 (V1) will change the shape of the injection passage 4A (4B) in the clamp section 7A (7B) where the divided bodies V1 and V2 are combined. As a result, it becomes possible to change and optimize the degree of vulcanization of the green tire G.

Reference Signs List 1 Vulcanization device 2 Vertically movable plate section 3 Central mechanism 3a Central post 4A, 4B Injection channel 4h Injection port 5 Discharge channel 5h Discharge port 6 Vulcanization bladder 6a Opening edge section 6b Outer circumferential end 7A, 7B Clamp section V1, V2 Divided body 8 Projection section 9 Vulcanization mold 9A Upper side mold 9B Lower side mold 9C Sector mold 10 Bead ring 11A Heating medium supply source 11B Pressurizing medium supply source 12 Upper plate 13 Lower plate 14 Segment 15 Container ring f Fixing member Mh Heating medium Mp Pressurizing medium G Green tire T Vulcanized tire

Claims (8)

A tire vulcanization apparatus comprising a central mechanism having a cylindrical vulcanization bladder inserted vertically therethrough, a vulcanization mold disposed so as to surround the central mechanism, an opening/closing means for opening and closing the vulcanization mold, a supply source for supplying a heating medium and a pressurizing medium to the inside of the vulcanization bladder, and an injection path extending vertically through the central mechanism to communicate between the supply source and the inside of the vulcanization bladder, wherein upper and lower opening edge portions of the vulcanization bladder are respectively held by disk-shaped clamp portions attached to the central mechanism at intervals vertically, and the heating medium and the pressurizing medium supplied through the injection path are injected into the inside of the vulcanization bladder from an injection port of the injection path located inside the vulcanization bladder,
A tire vulcanizing apparatus characterized in that each of the clamping sections is constructed by stacking vertically divisible divided bodies, the vertical gaps between the divided bodies constituting each of the clamping sections are connected to the injection passage, thereby forming a part of the injection passage and the injection inlet, the injection inlets are arranged continuously or intermittently around the entire circumferential direction at the outer circumferential end positions of each of the clamping sections, and the injection inlets are located outer than the outer circumferential end of the opening edge held by each of the clamping sections. The tire vulcanizing device according to claim 1, wherein the injection port is formed continuously around the entire circumference of the outer peripheral end surface of each of the clamping portions. The tire vulcanizing apparatus according to claim 1, wherein at least one of the divided bodies of each of the clamping parts has a protrusion protruding from a surface facing the other divided body to be stacked, the protrusion defines the injection passage in each of the clamping parts, the injection passage in each of the clamping parts extends radially from a center in a plan view, and the injection ports are intermittently formed on the outer peripheral end surface of each of the clamping parts all around the circumference. The tire vulcanizing device according to claim 3, wherein each of the injection passages extending radially from the center of each of the clamping parts in a plan view is formed in a fan shape that gradually widens toward the injection port, and the injection port is formed intermittently around the entire circumference of the outer peripheral end face of each of the clamping parts. The tire vulcanizing apparatus according to claim 3, wherein each of the injection passages extending radially from the center of each of the clamping parts in a plan view gradually tapers toward the injection port, and the injection port is intermittently formed around the entire circumference of the outer peripheral end face of each of the clamping parts. The tire vulcanizing apparatus according to claim 3, wherein each of the injection passages extending radially from the center of the clamp portion in a plan view is curved in the same direction toward the injection port. A tire vulcanization method comprising the steps of: inserting a green tire into a cylindrical vulcanization bladder having upper and lower opening edges respectively held by disk-shaped clamps attached at intervals above and below a central mechanism; arranging the green tire horizontally in a vulcanization mold installed so as to surround the central mechanism with the vulcanization mold opened; then closing the vulcanization mold; and injecting a heating medium and a pressurizing medium supplied from a supply source through an injection passage extending above and below the central mechanism into the vulcanization bladder from an injection port of the injection passage located inside the vulcanization bladder, thereby expanding the vulcanization bladder to vulcanize the green tire,
A tire vulcanization method comprising the steps of: constructing each of the clamping portions by stacking vertically divisible segments; communicating the vertical gaps between the segments constituting each of the clamping portions with the injection passage and utilizing them as part of the injection passage and the injection inlet; arranging the injection inlets continuously or intermittently around the entire circumferential direction at the outer circumferential end positions of each of the clamping portions; and positioning the injection inlets on the outer circumferential side of the outer circumferential end of the opening edge portion held by each of the clamping portions. The tire vulcanization method according to claim 7, in which a plurality of sets of the divided bodies are prepared, each set having a different shape in plan view of the injection passage in the clamp section, and one set is selected and used from the plurality of sets of the divided bodies according to the specifications of the green tire to be vulcanized.

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