Tire vulcanization apparatus and method

Abstract

To provide a tire vulcanization device and method capable of more efficiently heating sector molds assembled in an annular shape in a plan view by using an induction heating coil.SOLUTION: In a tire vulcanization device, each sector mold 7C has an outer peripheral surface flat recessed part 8a formed flat on an outer peripheral surface in a plan view, and a flat portion 10 of a conductor plate 9 is attached to the outer peripheral surface flat recessed part 8a in such a manner as to face and abut the outer peripheral surface flat recessed part 8a. The conductor plate 9 is formed of a material having magnetic permeability higher than that of the sector mold 7C. A green tire G is horizontally disposed in an opened mold 7. A plurality of sector molds 7C arranged so as to surround a center mechanism 3 are assembled in an annular shape, and the mold 7 is closed. The conductor plate 9 is heated by using an induction heating coil 11 arranged on an outer peripheral side of the conductor plate 9, and heat of the heated conductor plate 9 is conducted to the sector mold 7C to vulcanize the green tire G.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to a tire vulcanizing apparatus and method, and more particularly to a tire vulcanizing apparatus and method capable of more efficiently heating a sector mold assembled in an annular shape in a plan view using an induction heating coil.

Background Art

[0002] When vulcanizing a green tire in a tire vulcanization process, various methods of heating a mold using an induction heating coil have been proposed (see, for example, Patent Document 1). When the mold is formed of aluminum or the like having a lower magnetic permeability than iron or the like, the temperature of the mold cannot be rapidly increased even if the mold is directly heated using an induction heating coil.

[0003] Therefore, in conventional technologies such as Patent Document 1, a heating element formed of a material having a high magnetic permeability such as iron is interposed between the induction heating coil and the mold. Thereby, the heating element is rapidly heated using the induction heating coil, and the mold is rapidly heated by conducting the heat of the heated heating element to the mold.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] A sectional-type mold has multiple sector molds assembled in a ring shape in plan view. The outer surface of each sector mold is arc-shaped in plan view. The heating element, which is installed between the induction heating coil and the sector mold, is mounted in contact with the arc-shaped outer surface of the sector mold in plan view. Therefore, the inner surface of the heating element is formed in an arc shape in plan view to match the arc-shaped outer surface of the sector mold.

[0006] It was found that when this heating element is heated using an induction heating coil, it undergoes thermal deformation, changing the radius of curvature of its inner surface and creating a gap between it and the outer surface of the sector mold. This gap significantly hinders heat conduction between the heating element and the sector mold, resulting in the problem of not being able to heat the sector mold quickly. Therefore, there is room for improvement in heating sector molds, which are assembled in a ring shape in plan view, more efficiently using an induction heating coil. [Means for solving the problem]

[0007] To achieve the above objective, the tire vulcanization apparatus of the present invention comprises a central mechanism through which a cylindrical vulcanization bladder is inserted vertically, a vulcanization mold having a plurality of sector molds arranged in an annular shape and positioned around the central mechanism, an opening and closing means for opening and closing the vulcanization mold, and an induction heating coil for heating the vulcanization mold, The vulcanizing mold has a plurality of segments arranged in a ring shape surrounding the central mechanism, with each sector mold attached to the inner surface of the corresponding segment, and the opening and closing means has a cylindrical container ring centered on the central mechanism, the container ring has an inner inclined surface on its inner surface that slopes downward from above toward the outer surface, each segment has an outer inclined surface on its outer surface that slopes downward from above toward the outer surface, the inner inclined surface and the outer inclined surface of each segment are arranged to face each other, and the vulcanizing mold is closed when the outer inclined surface of each segment is pressed by the inner inclined surface of the container ring as it moves downward. Each of the sector molds has an outer peripheral flat portion formed flat on its outer surface in a plan view, and comprises a conductor plate having a flat portion that abuts against this outer peripheral flat portion, wherein the conductor plate is made of a material with higher magnetic permeability than the sector mold, and the induction heating coil is arranged on the outer peripheral side of the conductor plate.

[0008] The present invention relates to a tire vulcanization method in which a green tire is placed horizontally in an open vulcanization mold, and a plurality of sector molds are arranged in a ring shape in plan view around a central mechanism through which a cylindrical vulcanization bladder is inserted vertically, and the sector molds are assembled in a ring shape to close the mold, and the vulcanization mold is heated using an induction heating coil to vulcanize the green tire. Multiple segments are arranged in a ring shape surrounding the central mechanism, and each of the sector molds is attached to the inner surface of the corresponding segment. A cylindrical container ring centered on the central mechanism is used as an opening and closing means for opening and closing the vulcanizing mold, the container ring having an inner inclined surface that slopes downward from above toward the outer circumference, and each of the segments having an outer inclined surface that slopes downward from above toward the outer circumference, the inner inclined surface and the outer inclined surface of each segment are arranged to face each other, and the vulcanizing mold is closed by pressing the outer inclined surface of each segment with the inner inclined surface of the container ring moving downward. Each of the sector molds is provided with an outer surface flat portion formed flat on its outer surface in a plan view, and a flat portion of a conductor plate is attached in contact with this outer surface flat portion. The conductor plate is made of a material with a higher magnetic permeability than the sector mold, and the conductor plate is heated using the induction heating coil placed on the outer surface of the conductor plate, and the heat from the heated conductor plate is conducted to the sector mold to heat it. [Effects of the Invention]

[0009] According to the present invention, in a plan view, the outer peripheral flat portion formed on the outer peripheral surface of each sector mold and the flat portion of the conductor plate face each other and are in contact. Since the flat surfaces of the outer peripheral flat portion and the flat portion of the conductor plate are in surface contact with each other, it is advantageous in preventing the sector mold and the conductor plate from separating due to thermal deformation. Furthermore, by using the induction heating coil, the conductor plate, which has a higher magnetic permeability than the sector mold, is heated, and the heat from the heated conductor plate is quickly conducted to the sector mold, thereby efficiently heating the sector mold. [Brief explanation of the drawing]

[0010] [Figure 1] This is an explanatory diagram illustrating the left half of an embodiment of a tire vulcanization apparatus in a longitudinal cross-sectional view. [Figure 2] This is an explanatory diagram illustrating the segment and sector mold in Figure 1 in a plan view. [Figure 3] This is an explanatory diagram illustrating an enlarged view of the integrated segment and sector mold shown in Figure 1. [Figure 4] It is an explanatory diagram illustrating the integrated object in FIG. 3 from the perspective of the outer peripheral surface side. [Figure 5] It is an explanatory diagram illustrating the integrated object in FIG. 3 in a plan view. [Figure 6] It is an explanatory diagram illustrating the state before integrating the segment and the sector mold. [Figure 7] It is an explanatory diagram illustrating the state of FIG. 6 in a plan view. [Figure 8] It is an explanatory diagram illustrating the state of attaching the conductor plate to the sector mold in FIG. 6 from the perspective of the outer peripheral surface side. [Figure 9] It is an explanatory diagram illustrating the state of attaching the induction heating coil to the segment in FIG. 6 from the perspective of the inner peripheral surface side. [Figure 10] It is an explanatory diagram illustrating the state where the vulcanization mold in FIG. 1 is open. [Figure 11] It is an explanatory diagram illustrating the segment and the sector mold in the closed state in a plan view. [Figure 12] It is an explanatory diagram illustrating a tire vulcanizing apparatus for vulcanizing a green tire. [Figure 13] It is an explanatory diagram illustrating the segment and the sector mold in a cross-sectional view taken along the line A - A in FIG. 12. [Figure 14] It is an explanatory diagram showing a modified example of the sector mold and the conductor plate in a plan view. [Figure 15] It is an explanatory diagram illustrating the state of attaching the conductor plate to the sector mold in FIG. 14 from the perspective of the outer peripheral surface side. [Figure 16] It is an explanatory diagram showing another modified example of the sector mold in a plan view.

Embodiments for Carrying Out the Invention

[0011] Hereinafter, the tire vulcanizing apparatus and method of the present invention will be described based on the embodiments shown in the figures.

[0012] The tire vulcanizing apparatus 1 of the present invention illustrated in FIGS. 1 and 2 (hereinafter referred to as the vulcanizing apparatus 1) includes a central mechanism 3, a cylindrical vulcanizing bladder 5 held by the central mechanism 3, a vulcanizing mold 7 (hereinafter referred to as the mold 7), opening and closing means (the vertically moving plate portion 2 and the container 15 described later) for opening and closing the mold 7, a conductor plate 9, and an induction heating coil 11 for heating the mold 7 (upper side mold 7A, lower side mold 7B, sector mold 7C). In FIG. 1, the left half of the vulcanizing apparatus 1 is illustrated, but the right half has substantially the same structure as the left half.

[0013] The central mechanism 3 has a central post 3a and a disk-shaped clamp portion 6a attached to the central post 3a with a vertical interval. The central post 3a penetrates the vulcanizing bladder 5 vertically. The upper opening edge portion of the vulcanizing bladder 5 is sandwiched and held between a bead ring 6b attached to the lower surface on the inner peripheral side of the upper side mold 7A and the upper clamp portion 6a. The lower opening edge portion of the vulcanizing bladder 5 is sandwiched and held between a bead ring 6b attached to the upper surface on the inner peripheral side of the lower side mold 7B and the lower clamp portion 6a. The dashed-dotted line CL in FIG. 1 indicates the axial position of the central post 3a.

[0014] The central post 3a has an injection port 4a and a discharge port 4b at a position between the upper clamp portion 6a and the lower clamp portion 6a. The injection port 4a and the discharge port 4b are respectively connected to pipes extending downward from the central post 3a. A heating medium such as steam or a pressurizing medium such as nitrogen gas (hereinafter, the heating medium and the pressurizing medium are collectively referred to as the vulcanizing medium M) is injected into the vulcanizing bladder 5 from the injection port 4a.

[0015] The mold 7 is of a sectional type and has an annular upper side mold 7A, an annular lower side mold 7B, and a plurality of sector molds 7C. In this embodiment, the upper side mold 7A and the lower side mold 7B are made of iron, and each sector mold 7C is made of aluminum or an aluminum alloy.

[0016] The upper side mold 7A is attached to the lower surface of the upper plate 12. An induction heating coil 11 is positioned between the upper side mold 7A and the upper plate 12. The lower side mold 7B is fixed in place on the upper surface of the lower plate 13, which is fixed to the base. An induction heating coil 11 is positioned between the lower side mold 7B and the lower plate 13.

[0017] Each sector mold 7C is arc-shaped in plan view and is arranged in a ring around the central post 3a. Similarly, the same number of segments 14 are arranged in a ring around the central post 3a in plan view, with each sector mold 7C attached to the inner surface of the corresponding segment 14. A conductor plate 9 and an induction heating coil 11 are positioned between each sector mold 7C and each segment 14. Details of the integrated sector mold 7C and segment 14 will be described later.

[0018] Each segment 14 has an outer circumferential inclined surface that slopes downward from above toward the outer circumferential side. Each segment 14 has a guide groove that extends vertically along its outer circumferential inclined surface. In this embodiment, each segment 14 is made of iron.

[0019] 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 a cylindrical body centered on the central mechanism 3 (central post 3a), and moves up and down together with the vertically moving plate section 2 on the outer circumference of each segment 14. The vertically moving plate section 2 and the container ring 15, as well as the upper plate 12 and upper side mold 7A, move up and down independently by hydraulic cylinders.

[0020] The container ring 15 has an inner circumferential inclined surface that slopes downward from above toward the outer circumference. This inner circumferential inclined surface and the outer circumferential inclined surfaces of each segment 14 are arranged to face each other. Multiple guide keys are spaced apart in the circumferential direction on the inner circumferential inclined surface of the container ring 15 and extend vertically along this surface. Each guide key engages with a guide groove of the corresponding segment 14, and the guide key (inner circumferential inclined surface of the container ring 15) and the guide groove (outer circumferential inclined surface of each segment 14) slide against each other.

[0021] As illustrated in Figures 3 to 5, each sector mold 7C is attached to the corresponding segment 14 by screws or the like. The outer surface of the sector mold 7C and the inner surface of the segment 14 face each other, with the conductor plate 9 and induction heating coil 11 interposed between these outer and inner surfaces.

[0022] Figures 6 to 9 illustrate the state in which the integrated sector mold 7C and segment 14 are separated into their component parts.

[0023] Each sector mold 7C has a flat outer surface portion (outer surface flat recess 8a) formed flatly on its outer surface. This outer surface flat recess 8a is shaped as a portion of the arc-shaped outer surface of the sector mold 7C being removed into a flat surface in a plan view. In Figure 7, the arc-shaped outer surface of the sector mold 7C without the outer surface flat recess 8a is shown by a dashed line. In addition to forming the outer surface flat recess 8a by cutting the arc-shaped outer surface of the sector mold 7C into a flat surface, a sector mold 7C with the outer surface flat recess 8a may also be cast.

[0024] The outer circumferential flat recess 8a is not limited to a rectangular shape in front view as in this embodiment, but can be any shape. The size (total area) of the outer circumferential flat recess 8a should be, for example, 10% or more, more than 20% or more of the total area of ​​the outer circumferential surface of the sector mold 7C, and the outer circumferential flat recess 8a should be formed in a range that includes the central part of the outer circumferential surface in front view.

[0025] The conductor plate 9 has a flat portion 10 which is formed flat and abuts against the flat recess 8a on the outer circumferential surface. That is, the sector mold 7C and the conductor plate 9 are integrated by making surface contact between their respective flat portions 8a and 10 (flat surfaces). The conductor plate 9 and the sector mold 7C are fixed together with screws or the like. The conductor plate 9 is made of a material with a higher magnetic permeability than the sector mold 7C. Since the sector mold 7C is made of aluminum or an aluminum alloy, the conductor plate 9 is made of, for example, iron, pure iron, stainless steel, permalloy, etc.

[0026] The conductor plate 9 is not limited to a simple rectangular thin plate shape with flat surfaces on both sides, as in this embodiment, but can be any shape having a flat portion 10. The size (total area) of the conductor plate 9 should be, for example, 10% or more, 20% or more, of the total area of ​​the outer circumferential surface of the sector mold 7C, and should be positioned in a range that includes the central part of the outer circumferential surface of the sector mold 7C when viewed from the front. The contact area between the outer circumferential surface flat recess 8a and the flat portion 10 should be, for example, 10% or more, more, 20% or more of the total area of ​​the outer circumferential surface of the sector mold 7C.

[0027] The induction heating coil 11 can utilize various known specifications used for electromagnetic induction heating. The mold 7 is heated by passing an alternating current of a predetermined frequency through the induction heating coil 11. The frequency of the alternating current flowing through the induction heating coil 11 is set to an appropriate frequency, after pre-determining the range suitable for the vulcanization of the green tire G. In the vulcanization process, the green tire G is heated to, for example, 150°C to 200°C, so the induction heating coil 11 is set to flow an alternating current of a frequency suitable for heating to this temperature. Since the alternating current flowing through each induction heating coil 11 can be controlled individually, it is possible to set the heating temperatures of the upper side mold 7A, the lower side mold 7B, and each sector mold 7C to different temperatures, as well as the same temperature.

[0028] Each segment 14 has a housing chamber 14a that opens to its inner circumferential surface. This housing chamber 14a is formed in a position corresponding to the outer circumferential surface flat recess 8a or the conductor plate 9. An induction heating coil 11 used to heat the sector mold 7C is installed in this housing chamber 14a. The induction heating coil 11 that heats the sector mold 7C only needs to be positioned on the outer circumferential side of the conductor plate 9 fixed to the sector mold 7C. Therefore, the installation position of the induction heating coil 11 is not limited to the housing chamber 14a, but can also be, for example, on the outer circumferential surface of the segment 14.

[0029] Next, we will explain an example of a procedure for manufacturing a pneumatic tire T by vulcanizing a green tire G using this vulcanizing apparatus 1.

[0030] When vulcanizing the green tire G, the mold 7 is opened wide, and the green tire G is placed on its side on the lower side mold 7B. The lower bead core of the green tire G is placed on the lower bead ring 6b. The vulcanizing bladder 5 is slightly expanded to hold the green tire G in place.

[0031] Next, as illustrated in Figure 1, the upper side mold 7A is moved downward together with the upper plate 12 which is in an upper standby position, and the container ring 15 and each segment 14 are moved downward together with the vertically moving plate 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 plate 12 and the lower plate 13. In this state, as illustrated in Figure 2, each sector mold 7C (segment 14), which is arranged in a ring shape in a plan view, is in an expanded position.

[0032] Next, the container ring 15 is moved further downward together with the vertically moving plate 2, from the state shown in Figure 1 to the state shown in Figure 10. As a result, the outer circumferential inclined surface of each segment 14 is pressed against the inner circumferential inclined surface of the downward-moving container ring 15. Consequently, as shown in Figure 11, each sector mold 7C moves closer to the central post 3a, and these sector molds 7C are assembled in a ring shape, closing the mold 7.

[0033] After closing the mold 7, the vulcanizing medium M is injected into the vulcanizing bladder 5 from the injection port 4a, as illustrated in Figure 12. This causes the vulcanizing bladder 5 to expand sufficiently, pressing the green tire G against the inner surface of the mold 7 for vulcanization. The mold 7 is also heated using the respective induction heating coils 11. In this way, the green tire G is pressed against the inner surface of the mold 7 and heated, and after a predetermined time has elapsed, the vulcanization process is completed and the tire T is manufactured. After that, the upper movable plate section 2 and the container ring 15 are moved upward to open the mold 7, and the tire T is removed from the mold 7. Note that the present invention is not limited to pneumatic tires T, but can be applied to the manufacture of various other types of tires.

[0034] In the vulcanization process, the upper side mold 7A and the lower side mold 7B are directly heated by induction heating coils 11 positioned adjacent to each of them. Each sector mold 7C is heated via a conductive plate 9, rather than directly by induction heating coils 11 installed in the housing chamber 14a of the segment 14 to which it is attached.

[0035] More specifically, as illustrated in Figure 13, a conductor plate 9 is positioned between the flat recess 8a on the outer surface of the sector mold 7C and the induction heating coil 11. The conductor plate 9, which is directly heated by the induction heating coil 11, is made of a material with a higher magnetic permeability than the sector mold 7C and is therefore heated rapidly. The conductor plate 9 undergoes thermal deformation when heated. Since the conductor plate 9 and the sector mold 7C are made of different materials, their coefficients of thermal expansion are also different.

[0036] The sector mold 7C and the conductor plate 9 are in contact with each other, with the outer surface flat recess 8a and the flat portion 10 facing each other. That is, the flat surfaces of the outer surface flat recess 8a and the flat portion 10 are in surface contact, so even if the sector mold 7C and the conductor plate 9 undergo thermal deformation due to their respective coefficients of thermal expansion, the outer surface flat recess 8a and the flat portion 10 are unlikely to separate, and a gap is unlikely to form between them. Therefore, the reduction in the contact area between the outer surface flat recess 8a and the flat portion 10 is suppressed.

[0037] A reduction in the contact area between the outer surface flat recess 8a and the flat portion 10 significantly reduces heat conduction from the conductor plate 9 to the sector mold 7C. However, according to the present invention, this reduction in contact area is suppressed, so that the heat from the rapidly heated conductor plate 9 is quickly conducted to the sector mold 7C through the flat portion 10 and the outer surface flat recess 8a. Therefore, the sector mold 7C can be efficiently heated with minimal heat conduction loss of the thermal energy supplied by the induction heating coil 11. Consequently, this is advantageous for manufacturing the tire T by vulcanizing the green tire G in an energy-saving manner.

[0038] In this embodiment, the induction heating coil 11 for heating the sector mold 7C is located inside the segment 14 to which the sector mold 7C is attached. Compared to the case where the induction heating coil 11 is located on the outer circumferential surface of the sector mold 7C, the induction heating coil 11 is positioned closer to the sector mold 7C. Therefore, it is advantageous for quickly and efficiently conducting the thermal energy supplied by the induction heating coil 11 to the sector mold 7C via the conductive plate 9.

[0039] In the embodiment described above, each sector mold 7C is configured to have only one outer surface flat recess 8a, but it is also possible to have multiple outer surface flat recesses 8a, as illustrated in Figures 14 and 15. The conductor plate 9 is attached to each outer surface flat recess 8a by bringing its flat portion 10 into contact with it.

[0040] In Figures 14 and 15, three circumferential flat recesses 8a are formed on the sector mold 7C at intervals in the circumferential direction. However, the number of circumferential flat recesses 8a is not limited to three; there may be two or four or more. In Figure 14, the arc-shaped circumferential surface of the sector mold 7C without circumferential flat recesses 8a is shown by a dashed line. To increase the area of ​​the flat surface with only one circumferential flat recess 8a, a large amount of material needs to be removed from the circumferential surface of the sector mold 7C. On the other hand, as illustrated in Figures 14 and 15, dividing the circumferential flat recesses 8a into multiple sections in the circumferential direction is advantageous in reducing the material needed to remove from the circumferential surface of the sector mold 7C and increasing the total area of ​​the circumferential flat recesses 8a.

[0041] As illustrated in Figure 16, the sector mold 7C can also be made to have a flat protrusion 8b on its outer surface instead of a flat recess 8a. The flat protrusion 8b on the outer surface has a shape in which a part of the arc-shaped outer surface of the sector mold 7C is built up on a flat surface in a plan view. The conductor plate 9 is attached to the flat protrusion 8b by bringing its flat portion 10 into contact with it. In Figure 16, the arc-shaped outer surface of the sector mold 7C when the flat protrusion 8b is not present is shown by a dashed line. In addition to casting a sector mold 7C with the flat protrusion 8b, it is also possible to form the flat protrusion 8b on the outer surface by cutting a part of the arc-shaped outer surface of the sector mold 7C into a flat surface.

[0042] If the sector mold 7C has a specification that includes a flat protrusion 8b on its outer surface, the radial thickness of the sector mold 7C will not be reduced in order to provide a flat surface on its outer surface. Therefore, sector molds 7C that are difficult to reduce in radial thickness should be made to have a specification that includes a flat protrusion 8b on their outer surface. Similar to the flat recess 8a on the outer surface, multiple flat protrusions 8b can be formed on a single sector mold 7C. [Examples]

[0043] A vulcanizing apparatus (Example) equipped with a typical automotive vulcanizing mold as illustrated in Figures 1 to 5, and a vulcanizing apparatus (Comparative Example) differing only from the Example in that the sector mold has an arc-shaped outer surface without flat recesses on the outer surface, and a curved conductor plate along this outer surface is in contact with this outer surface, were used. The temperature change of the sector mold over time was measured by passing an alternating current under the same conditions through an induction heating coil. The contact area between the conductor plate and the outer surface of the sector mold before heating was set to 180 mm × 180 mm. The sector mold was made of aluminum, and the conductor plate was made of iron.

[0044] As a result, in the example, the sector mold heated up to 160°C within 30 minutes of the start of measurement. There was almost no change in the contact area between the conductor plate and the outer surface of the sector mold. In the comparative example, the heated conductor plate underwent thermal deformation, and the contact area between the conductor plate and the outer surface of the sector mold decreased significantly. Therefore, the sector mold only heated up to about 60°C within 30 minutes of the start of measurement, and did not reach 160°C thereafter. [Explanation of Symbols]

[0045] 1. Vulcanizing apparatus 2. Vertically movable plate section 3 Central mechanism 3a Central Post 4a inlet 4b Outlet 5. Bladder for vulcanization 6a Clamp section 6b Beading 7. Vulcanizing mold 7A Upper side mold 7B Lower side mold 7C Sector Mold 8a Outer surface flat recess (outer surface flat portion) 8b Outer surface flat protrusion (outer surface flat portion) 9 Conductor plate 10 Flat area 11 Induction heating coil 12 Top plate 13 Lower plate 14 segments 14a Confinement Room 15 Container Rings G Green Tire T vulcanized tires

Claims

1. A tire vulcanizing apparatus comprising a central mechanism through which a cylindrical vulcanizing bladder is inserted vertically, a vulcanizing mold having a plurality of sector molds arranged in an annular shape surrounding the central mechanism, an opening and closing means for opening and closing the vulcanizing mold, and an induction heating coil for heating the vulcanizing mold, The central mechanism has multiple segments arranged in a ring shape, and each of the sector molds is attached to the inner surface of the corresponding segment. The opening and closing means has a cylindrical container ring centered on the central mechanism, The container ring has an inner circumferential inclined surface that slopes downward from above toward the outer circumference, and each of the segments has an outer circumferential inclined surface that slopes downward from above toward the outer circumference, and the inner circumferential inclined surface and the outer circumferential inclined surface of each of the segments are arranged to face each other. The vulcanizing mold is closed by pressing the outer circumferential inclined surface of each segment against the inner circumferential inclined surface of the container ring, which moves downward. A tire vulcanizing apparatus comprising: each of the sector molds having an outer peripheral flat portion formed flat on its outer peripheral surface in a plan view, and a conductor plate having a flat portion that abuts against the outer peripheral flat portion, wherein the conductor plate is made of a material with higher magnetic permeability than the sector mold, and the induction heating coil is positioned on the outer peripheral side of the conductor plate.

2. The tire vulcanizing apparatus according to claim 1, wherein the induction heating coil is located inside the segment attached to the outer circumferential surface of each of the sector molds.

3. The tire vulcanizing apparatus according to claim 1 or 2, wherein the outer peripheral flat portion has a shape in which a part of the arc-shaped outer peripheral surface of each sector mold is removed to form a flat surface in a plan view.

4. The tire vulcanizing apparatus according to claim 1 or 2, wherein the flat outer surface portion has a shape in which a part of the arc-shaped outer surface of each sector mold is built up on the flat surface when viewed from above.

5. The tire vulcanizing apparatus according to any one of claims 1 to 4, wherein each of the sector molds has a plurality of flat portions on its outer surface.

6. In a tire vulcanization method, a green tire is placed horizontally inside an open vulcanizing mold, and the vulcanizing mold has a plurality of sector molds arranged in a ring shape in plan view, surrounding a central mechanism through which a cylindrical vulcanizing bladder is inserted vertically. The sector molds are then assembled in a ring shape to close the mold, and the vulcanizing mold is heated using an induction heating coil to vulcanize the green tire. Multiple segments are arranged in a ring shape to surround the central mechanism, and each of the sector molds is attached to the inner surface of the corresponding segment. As an opening and closing means for opening and closing the vulcanizing mold, a cylindrical container ring centered on the central mechanism is used, the container ring has an inner circumferential inclined surface that slopes downward from above toward the outer circumference, and each of the segments has an outer circumferential inclined surface that slopes downward from above toward the outer circumference, and the inner circumferential inclined surface and the outer circumferential inclined surface of each segment are arranged to face each other, and the vulcanizing mold is closed by pressing the outer circumferential inclined surface of each segment with the inner circumferential inclined surface of the container ring moving downward. A tire vulcanization method comprising: providing each of the sector molds with an outer surface flat portion formed flat on its outer surface in a plan view, attaching a flat portion of a conductor plate in contact with this outer surface flat portion, forming the conductor plate from a material with higher magnetic permeability than the sector mold, heating the conductor plate using the induction heating coil placed on the outer surface of the conductor plate, and conducting the heat from the heated conductor plate to the sector mold to heat it.

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