JP2007234513A - High-frequency induction heating device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To evenly heat a cylindrical material to be heated by high frequency induction. <P>SOLUTION: A vulcanizing-molding apparatus 10 has an inner die 20 and an outer die 40. The material 30 to be heated formed cylindrically is placed on an outer periphery surface 27 of the inner die 20. The outer die 40 has a nearly cylindrical storage chamber 67, and a rubber jacket 43 is provided on an inner periphery surface. A cylindrical electrode part 65 is provided along the inner periphery surface of the storage chamber 67. A subsidiary material 90 formed of a vulcanized rubber cylinder for keeping the material 30 to be heated warm is provided on an inner periphery side of the electrode part 65. The inner die 20 to which the material 30 to be heated is placed is arranged on an inner periphery side of the subsidiary material 90. The rubber jacket 43 is expanded to the inner periphery side, and the subsidiary material 90 and the material 30 to be heated are pinched together with the inner die 20 through an electrode member 60. A high frequency voltage is applied between the electrode member 65 and the inner die 20 to heat the material 30 to be heated. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a high-frequency dielectric heating device applied to, for example, a vulcanization molding device.

  Conventionally, a one-pot type vulcanization molding apparatus is known as an apparatus for pressurizing and heating a sleeve-like material to be heated (for example, Patent Document 1). In this vulcanization molding apparatus, the material to be heated is disposed between a cylindrical outer mold and an inner mold disposed concentrically inside the outer mold, and heat supplied to the outer mold and the inner mold. While being heated by the medium, it is sandwiched between the outer mold and the inner mold, and is vulcanized and molded by being heated and pressurized.

  In this one-pot vulcanization molding apparatus, the heat energy of the heat medium supplied to the outer mold or the inner mold is thermally conducted from the outer peripheral surface and the inner peripheral surface of the heated material to the heated material, thereby The entire material to be heated is heated. However, when the material to be heated is made of, for example, rubber or resin, its thermal conductivity is generally low, and heat by heat conduction does not sufficiently conduct heat energy inside the material to be heated.

  Therefore, in recent years, methods for heating a material to be heated from the inside thereof are being studied, and as one of the methods, a method for heating the material to be heated between electrodes and heating it by high frequency dielectric heating is being proposed.

  For example, when heating a material to be heated that has a cylindrical shape by high-frequency dielectric heating, a holder holding the material to be heated is placed between the upper electrode and the lower electrode, and the material to be heated is rotated while rotating the material to be heated together with the holder. Patent Document 2 discloses a method for heating a material.

Patent Document 3 discloses a method in which an object to be heated is flattened and sandwiched between a pair of electrodes and a high frequency voltage is applied between the electrodes and heated. In this method, the material to be heated contacts an electrode made of a metal having a relatively high thermal conductivity, and the contact portion absorbs heat. Therefore, in order to prevent the heat absorption, the electrode itself is heated by a heating means (for example, steam or heat transfer heater) different from the high frequency dielectric heating.
JP 2000-824 A Japanese Patent Laid-Open No. 11-123758 Japanese Patent Laid-Open No. 9-289078

  However, according to the high-frequency dielectric heating described in Patent Document 2, extra power is required to rotate the holder, and the holder is made of fluororesin and has low elasticity so that sufficient pressure is applied to the material to be heated. I can't.

  Therefore, in the high frequency dielectric heating described in Patent Document 2, it is conceivable to omit the holder. However, if the heated material is not rotated by the holder, the high-frequency voltage is not uniformly applied to the cylindrical heated material, so that it is difficult to heat the heated material uniformly.

  In the method of Patent Document 3, when a heat transfer heater is used as the heating means, it takes a long time to raise the temperature of the electrode, and the structure of the electrode becomes complicated. In addition, when steam is used as a heating means, if steam enters between the electrodes, a spark is generated, and an explosive rupture occurs in the material to be heated. Therefore, measures must be taken to prevent steam leakage. In some cases, it is difficult to prevent steam leakage.

  Then, this invention is made in view of the said problem, and it aims at providing the high frequency dielectric heating apparatus which can heat the to-be-heated material which exhibits a cylindrical shape efficiently and uniformly. .

  A high-frequency dielectric heating device according to the present invention is a high-frequency dielectric heating device for applying a high-frequency voltage to a material to be heated formed in a cylindrical shape and heating the material by high-frequency dielectric, on the inner peripheral surface side of the material to be heated And at least one of the first and second electrodes disposed on the outer peripheral surface side and for applying a high-frequency voltage in the thickness direction of the material to be heated, and the first and second electrodes, And a sub-material including a cylindrical vulcanized rubber body that is disposed between the heated materials so as to be along the inner peripheral surface or the outer peripheral surface of the heated material. And

  This high-frequency dielectric heating device includes, for example, a columnar inner mold in which a material to be heated is mounted on the outer peripheral surface, and an outer mold that is disposed so as to surround the inner mold in which the material to be heated is mounted. When either one of the first and second electrodes is disposed between one of the inner mold and the outer mold and the material to be heated and exhibits a cylindrical shape, the auxiliary material exhibits a cylindrical shape. It is preferable to arrange between one electrode and the material to be heated.

  For example, the second electrode is one electrode having a cylindrical shape, and is disposed between the outer mold and the material to be heated, and the material to be heated is connected to the outside via the second electrode and the auxiliary material. It is pressed by the mold and clamped by the outer mold and the inner mold. Moreover, it is preferable that at least a part of the second electrode bends inward and is deformed by being pressed from the outer mold to press the auxiliary material. According to these configurations, since the auxiliary material includes the highly elastic vulcanized rubber body, when pressed by the outer mold, the auxiliary material can be properly adhered to the electrode and the material to be heated. Accordingly, the material to be heated can be appropriately pressurized and can be efficiently heated by the high frequency dielectric. In addition, the outer mold includes, for example, a jacket that presses the second electrode by expanding toward the inside. The jacket is preferably inflated by air pressure.

  For example, the outer surface of the inner mold is made of metal and serves as the first electrode. According to such a configuration, since the thermal conductivity of the outer peripheral surface of the inner mold is high and the material to be heated may be absorbed by the inner mold, the outer peripheral surface of the inner mold has a different heat from the heating by the high frequency voltage. Heating with a medium is preferred.

  The electrode disposed between one of the inner mold and the outer mold and the material to be heated is connected to a plurality of flexible thin plate portions separated in the circumferential direction and a plurality of thin plate portions in the circumferential direction. And a fixing portion to be provided. And it is preferable to arrange | position so that a some thin-plate part may respectively be along an outer peripheral surface of a to-be-heated material by deform | transforming inside toward a to-be-heated material.

  The first electrode is one electrode having a cylindrical shape, and is disposed between the inner mold and the material to be heated, and the material to be heated depends on the inner mold through the first electrode and the auxiliary material. It is preferably pressed and pinched by the outer mold and the inner mold. When the first electrode is pressed from the inner mold, it is preferable that at least a part of the first electrode bends outward and is deformed to press the auxiliary material.

  The inner mold preferably includes a jacket that presses the first electrode by expanding toward the outside. The jacket is preferably inflated by air pressure.

  The auxiliary material should be electrically insulated between any one of the electrodes and the material to be heated. Thereby, even if a high voltage is applied between both electrodes, no spark is generated between the material to be heated and the electrodes.

  The present invention relates to a manufacturing method for heating a heated material and manufacturing a heated heated material. In the present invention, first and second electrodes for applying a high-frequency voltage to the heated material are arranged on each of the inner peripheral surface side and the outer peripheral surface side of the heated material formed in a cylindrical shape, and the first And a cylindrical heating member for keeping the heated material between the at least one of the second electrodes and the heated material so as to follow the inner peripheral surface or the outer peripheral surface of the heated material. A secondary material including a vulcanized rubber body is disposed, a high frequency voltage is applied in a thickness direction of the heated material, and the heated material is heated by high frequency dielectric.

  In the present invention, by arranging the auxiliary material between the electrode and the material to be heated, when the material to be heated is heated by the high frequency dielectric, the material to be heated is kept warm by the auxiliary material. Can be heated. That is, since the material to be heated is not absorbed by the jacket disposed on the outer peripheral side, the material to be heated is heated evenly without heating the jacket.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a vulcanization molding apparatus according to the first embodiment. The vulcanization molding apparatus 10 has an inner mold 20 and an outer mold 40 for housing the inner mold 20 therein. The inner mold 20 is formed of metal in a substantially cylindrical shape, and a passage for allowing a heat medium or cooling water to pass therethrough is provided inside the inner mold 20, and the outer peripheral surface of the inner mold 20 is passed through the heat medium. 27 is heated. The upper and lower surfaces 22 and 23 of the inner mold 20 are respectively provided with inlet / outlet pipes 24 and 25 for sending and receiving the heat medium into and from the inner mold 20. The inlet / outlet pipes 24 and 25 protrude upward and downward from the centers of the upper surface 22 and the lower surface 23, respectively. As the heat medium, for example, water vapor, oil or the like is used.

  As shown in FIG. 2, a canvas 80 and an unvulcanized rubber sheet 81 are sequentially wound around the outer peripheral surface 27 of the inner mold 20 as the heated material 30, and the wound heated material 30 has a substantially cylindrical shape. By being wound in this way, the material to be heated 30 is attached to the inner mold 20 so that the inner peripheral surface 31 thereof follows the outer peripheral surface 27 of the inner mold 20. The substantially cylindrical heated material 30 has an axial length shorter than the axial length of the inner mold 20 as shown in FIG. 1, and the heated material at the lower end portion and the upper end portion of the inner mold 20. 30 is not wound. In addition, the to-be-heated material 30 is not limited to this structure, What is necessary is just what can be heated by a high frequency dielectric material, and should just contain various resin, an elastomer, a polymeric natural material, etc.

  The rubber sheet 81 may be further coated with a polytetrafluoroethylene sheet or the like. The polytetrafluoroethylene sheet has high releasability with respect to rubber, is not bonded to the rubber sheet by vulcanization, and does not constitute a belt or the like obtained by vulcanization as described later. When the polytetrafluoroethylene sheet is not coated, a release agent may be applied to the outer peripheral surface of the material to be heated 30. Thereby, the to-be-heated material 30 and the auxiliary material 90 can be released easily.

  The outer mold 40 includes an outer frame 41 having a substantially cylindrical shape with a bottom, an upper mold 42 fixed to the upper surface of the outer frame 41, and a rubber jacket 43 provided inside the outer frame 41. The outer frame 41 and the upper mold 42 are formed of metal so that current can be conducted. The bottom 50 of the outer frame 41 is formed in a stepped shape, and has a circular base bottom 47 provided with a substantially circular insertion hole 46 in the center, and rises from the outer peripheral edge of the base bottom 47 in the axial direction of the outer frame 41. The connecting portion 48 is connected to the side portion 72 of the outer frame 41. The connecting portion 48 is connected to the side surface 72 of the outer frame 41. A connection pipe 85 connected to the inlet / outlet pipe 25 when the inner mold 20 is stored is inserted into the insertion hole 46.

  The upper mold 42 includes annular first and second annular disks 42a and 42b, and a second annular disk 42b is overlapped on the first annular disk 42a. The inner diameters of the first and second annular disks 42a and 42b substantially coincide with each other, and the inner peripheral surfaces thereof serve as openings for inserting the inner mold 20. An annular bottom projection 56 and an upper projection 57 projecting downward and upward are connected to the inner edge of the lower surface of the first annular disk 42a and the inner edge of the middle bottom 49, respectively.

  The rubber jacket 43 has a cylindrical shape and is disposed concentrically with the outer frame 41, and is widened so that both ends of the cylindrical shape have a larger diameter, and on the outer peripheral side of the bottom surface protruding portion 56 and the top surface protruding portion 57. It is engaged with the side surface and fixed to the first annular disk 42 a and the middle bottom 49. The rubber jacket 43 is engaged with these protrusions, so that the rubber jacket 43 is maintained in a fixed state with respect to the upper mold 42 and the middle bottom 49 of the rubber jacket 43 even when pressed inward in the radial direction.

  With the above configuration, a sealed space 54 is formed between the rubber jacket 43 and the side surface 72 of the outer frame 41 with the middle bottom surface 49 as the bottom surface and the upper mold 42 as the top surface. On the other hand, the inner circumferential surface of the rubber jacket 43 forms substantially the same curved surface together with the inner circumferential surface of the upper mold 42 and the connection surface 48 of the bottom portion 50, whereby the same curved surface is used as the inner circumferential surface and the base bottom surface 47 is formed. A cylindrical storage chamber 67 serving as a bottom surface is provided.

  An electrode material 60 is provided on the radially inner side of the rubber jacket 43 (that is, the storage chamber 67). The electrode material 60 has an electrode portion 65 formed in a cylindrical shape and a flange portion 66 that spreads outward from the upper end portion of the electrode portion 65. The electrode portion 65 is concentrically provided on the outer frame 41 along the inner peripheral surface of the storage chamber 67 (that is, the rubber jacket 43, the inner peripheral surface of the first annular disk 42a, and the connection surface 48). The flange portion 66 of the electrode material 60 is sandwiched between the first and second annular disks 42 a and 42 b, whereby the electrode material 60 is fixed to the outer mold 40. A power source (not shown) for applying a high frequency voltage between the electrode material 60 and the inner mold 20 is connected to the electrode material 60 and the inner mold 20. Moreover, the lower end part of the electrode material 65 is supported by the connection part 48 so that a movement to an up-down direction is possible so that it may mention later.

  The outer frame 41 is provided with an inlet 52 and an outlet 53. A pressure medium is injected from the inlet 52 into the sealed space 54, and the pressure medium in the sealed space 54 is discharged from the outlet 53. Compressed air is used as the pressure medium.

  In the storage chamber 67, a cylindrical auxiliary material 90 is provided on the inner side in the radial direction of the electrode portion 65 so as to follow the inner peripheral surface of the electrode portion 65. The auxiliary material 90 is placed on the base surface 47, and the height thereof substantially matches the height of the storage chamber 67. The auxiliary material 90 is used to keep the heated material 30 warm when the heated material 30 is heated, and is composed only of a vulcanized rubber cylinder. The rubber components of the vulcanized rubber cylinder include natural rubber, styrene-butadiene rubber, chloroprene rubber, alkylated chlorosulfonated polyethylene, ethylene-propylene-diene terpolymer blend (EPDM), ethylene-propylene rubber (EPR). ), Simple substances such as nitrile rubber and hydrogenated nitrile rubber, or a mixture thereof. However, it is preferable to use a rubber component having excellent heat resistance such as EPDM. This is because when the vulcanized rubber layer is excellent in heat resistance, the auxiliary material can be used repeatedly. Also, it is better not to use a rubber component having a low dielectric loss coefficient such as silicon rubber as the rubber component of this embodiment.

  The vulcanized rubber cylinder preferably has a dielectric loss coefficient equal to or higher than that of the material to be heated 30. When the dielectric loss coefficient is set in this way, the auxiliary material 90 is also heated by the high-frequency dielectric together with the heated material 30, or the auxiliary material 90 is heated preferentially over the heated material 30, and the heated material of the auxiliary material 90 is heated. This is because the effect of keeping 30 warm is enhanced. The dielectric loss coefficient is a value defined by the product (εγ × tan δ) of the relative dielectric constant (εγ) and the dielectric loss angle (tan δ).

  The vulcanized rubber cylinder is obtained by vulcanizing and molding an unvulcanized rubber in which various additives such as a vulcanizing agent and a reinforcing agent are blended with an unvulcanized rubber composed of the rubber component. As the vulcanizing agent, a sulfur-based or peroxide-based vulcanizing agent can be used, but it is better to use a peroxide vulcanizing agent. This is because when the peroxide is used, the heat resistance of the auxiliary material is improved as compared with the case where the sulfur-based vulcanizing agent is used, and the auxiliary material can be used repeatedly. Further, as an additive, it is preferable that a metal-containing pigment such as a copper-containing pigment is added to the vulcanized rubber cylinder. This is because the metal that can be energized is dispersed in the secondary material that is an insulator, whereby the metal is energized and the heating of the secondary material is promoted by the dielectric of the surrounding insulator.

The vulcanized rubber cylinder is non-conductive, and its volume resistivity value is, for example, 1 × 10 ⁹ Ω · cm or more. Therefore, it is preferable not to use carbon black, which is a conductive substance, as the main reinforcing agent used in the vulcanized rubber cylinder. That is, the main reinforcing agent used for the vulcanized rubber cylinder is preferably a non-conductive substance, for example, silica. For example, 5 to 100 parts by weight of silica is blended with respect to 100 parts by weight of the rubber component. Carbon black may be blended as the reinforcing agent, but the blending amount of carbon black is less than the blending amount of silica, for example, blending at a ratio of 5 parts by weight or less with respect to 100 parts by weight of the rubber component. Of course, carbon black may not be blended in the vulcanized rubber cylinder.

  A cylindrical first insulating block 61 a is fixed to the upper surface of the upper mold 62. The first insulating block 61 a has an annular shape, and the inner peripheral surface thereof is disposed on the substantially same surface as the inner peripheral surface of the secondary material 90, thereby covering the upper side of the secondary material 90.

  In the storage chamber 67, an annular second insulating block 61 b is provided on the inner peripheral side of the auxiliary material 90. The second insulating block 61 b is formed so that the inner diameter thereof matches the diameter of the insertion hole 46 so as to avoid the insertion hole 46, and the outer peripheral surface thereof is along the inner peripheral surface of the auxiliary material 90. It is mounted on the upper surface. The upper surface of the second insulating block 61 b has an inner diameter such that the inner peripheral surface is along the outer peripheral surface of the inner mold 20 and the outer peripheral surface is formed along the inner peripheral surface of the auxiliary material 90. Three insulating blocks 61c are provided. Note that the second insulating block 61b and the third insulating block 61c may be formed integrally and may have an L-shaped cross section. The first to third insulating blocks 61a, 61b, 61c are formed of an insulator such as silicon or a fluororesin (for example, polytetrafluoroethylene).

  FIG. 3 shows a vulcanization molding apparatus when the inner mold 20 is housed in the outer mold 40. When the inner mold 20 to which the material to be heated 30 is attached is housed in the outer mold 40, the lower end portion of the inner mold 20 is inserted into the inner peripheral side of the third insulating block 61c, and the inner mold 20 The inlet / outlet pipe 25 is inserted into the inner periphery of the second insulating block 61b, and the lower surface 23 of the inner mold 20 is placed on the upper surface of the second annular block 61b. The lower surface of the material to be heated 30 is in contact with or close to the upper surface of the third insulating block 61c. When the inner mold 20 is housed in this way, the axes of the inner mold 20 and the outer mold 40 (outer frame 41) coincide with each other, the heated material 30 is arranged on the radially inner side of the auxiliary material 90, and the heated material 30 The outer peripheral surface of the sub-material 90 is disposed along the inner peripheral surface of the auxiliary material 90. Thus, when the inner mold 20 is housed in the outer mold 40, the inner mold 20, the outer mold 40, the material to be heated 30, the electrode material 65, and the auxiliary material 90 are provided concentrically, Match.

  When the inner mold 20 is stored in the storage chamber 67, conductive wires (not shown) are respectively connected to the inner mold 20 and the outer mold 40, and these conductive wires are connected to a power supply (not shown) for power supply. Connected. The outer mold 40 is electrically connected to the electrode section 65 via the upper mold 42 to which the electrode material 60 is attached and the connection section 48, and a high frequency voltage is applied between the electrode section 65 and the inner mold 20. Can be applied. In addition, connecting pipes 85 are connected to the inlet / outlet pipes 24 and 25 of the inner mold 20 in order to supply a heat medium. The connecting pipe 85 is made of an insulator such as silicon or fluororesin so as not to conduct the current supplied from the inner mold 20.

  An upper lid 95 is placed above the inner mold 20 stored in the storage chamber 67. The upper cover 95 includes an annular flat plate portion 96 provided with a hole 98 in the center, and an annular block portion 97 that protrudes from the lower surface of the annular flat plate portion 96 and has an outer peripheral surface provided on the same circumferential surface as the outer periphery of the annular flat plate portion 96. These are formed integrally and have an L-shaped cross section. The upper lid 95 is placed over the inner mold 20 by inserting the inlet / outlet pipe 24 into the hole 98 and placing the lower surface of the annular flat plate portion 96 on the upper surface 22 of the inner mold 20. At this time, the annular block portion 97 is disposed between the auxiliary material 90 and the inner mold 20 and in a gap formed on the heated material 30. As will be described later, when the heated material 30 expands upward by being clamped, the heated material 30 is stopped from above by the upper lid 95, thereby preventing the heated material 30 from jumping upward. Similarly, the auxiliary material 90 is prevented from jumping upward by the first insulating block 61a. The upper lid 95 is formed of an insulator such as silicon or a fluororesin (for example, polytetrafluoroethylene). The upper lid 95 is provided with a plurality of air vent holes 71 penetrating the annular block portion 97 and the annular flat plate portion 96 in the axial direction of the inner mold 20.

  Next, the heating / vulcanizing method in this embodiment will be described. In the present embodiment, in a state where the inner mold 20 is housed in the outer mold 40, a pressure medium is supplied to the sealed space 54 provided in the outer mold 40, and the rubber jacket 43 is expanded radially inward. . Due to the expansion of the rubber jacket 43, the cylindrical electrode portion 65 is reduced in diameter, deflected inward and displaced, and is in close contact with the auxiliary material 90. Then, the auxiliary material 90 and the material to be heated 30 are pressed against the rubber jacket 43 via the electrode portion 65, thereby being pinched by the rubber jacket 43 and the inner mold 20, and a predetermined pressure is urged.

  Along with this clamping pressure, a high frequency voltage is applied between the electrode material 60 and the inner mold 20. Here, the high frequency voltage is a high voltage (for example, 10,000 V), but the auxiliary material 90 is non-conductive and electrically insulates between the electrode material 60 and the inner mold 20. Even if a high voltage is applied between 60 and the inner mold 20, no spark or the like occurs between the electrodes.

  The heated material 30 is heated by the high frequency dielectric together with the auxiliary material 90 by application of the high frequency voltage. Here, the outer mold 40 and the electrode material 65 are made of metal, and the heat conductivity thereof is relatively high, while the auxiliary material 90 is made of a vulcanized rubber cylinder, and the heat conductivity is relatively low. Therefore, the auxiliary material 90 heated by the high frequency dielectric is absorbed by the outer mold 40 and the electrode material 60, but the heated material 30 is absorbed by the outer mold 40 and the electrode material 60 due to the heat insulating effect of the auxiliary material 90. There is almost no. Further, along with the application of the high frequency voltage, a heat medium is supplied into the inner mold 20 and the outer peripheral surface 27 of the inner mold 20 is heated. Therefore, the inner mold 20 is made of metal and has a high thermal conductivity, but the material to be heated 30 is hardly absorbed by the inner mold 20. Further, in the present embodiment, the upper lid 95 and the second and third insulating blocks 61b and 61c are provided above and below the heated material 30, respectively. There is almost no heat loss.

  That is, once the heat energy is given to the material to be heated 30 by the high frequency dielectric, the heat energy is hardly propagated to the inner mold 20 and the outer mold 40 and so on, so that any part is heated uniformly. In addition, the thermal energy generated by the high frequency dielectric can be used effectively.

  After the material to be heated 30 reaches a vulcanization temperature (for example, 160 ° C.), the vulcanization temperature is maintained for a predetermined time in a narrow pressure state, and vulcanization molding is performed. At this time, the application of the high frequency voltage may be continued, but the application of the high frequency voltage may be stopped. This is because the to-be-heated material 30 can maintain the vulcanization temperature for a predetermined time without being heated by the high frequency dielectric due to the heat retaining effect of the auxiliary material 90 and the heat medium in the inner mold 20.

  When the vulcanization molding is completed, cooling water is supplied into the inner mold 20, the heated material 30 is cooled, and then the inner mold 20 is taken out from the outer mold 40. After the inner mold 20 is taken out of the outer mold 40, the heated material 30 is removed from the inner mold 20, thereby obtaining a vulcanized cylindrical heated material. In the present embodiment, the vulcanized and molded material 30 to be heated is a belt slab in which the canvas 80 is vulcanized and bonded to one surface of the rubber sheet 81. The belt slab is polished and then cut in the width direction to form various belts such as a flat belt and a V belt. Of course, the material to be heated 30 may be molded into a material other than the belt slab by being heated and pressurized, for example, a rubber packing or a rubber roller.

  As described above, in the present embodiment, the material to be heated 30 can be uniformly heated without supplying a pressure medium that also serves as a heating medium such as steam into the outer mold. Compressed air can be used. Therefore, even if the pressure medium leaks into the storage chamber 67 due to the tearing of the rubber jacket 43 or the lack of sealing between the fixed portion of the outer mold 40 and the rubber jacket 43, the leaked pressure medium causes sparks to be heated. There is no explosive burst at 30. Further, the space inside the inner mold 20 is sufficiently sealed, and the heat medium supplied to the inside of the inner mold 20 does not leak into the storage chamber 67. Therefore, the heat medium supplied to the inside of the inner mold 20 Therefore, no spark is generated. In addition, since the auxiliary material 90 is formed of vulcanized rubber having high elasticity, the auxiliary material 90 can sufficiently adhere to the electrode portion 65 and the heated material 30 when being pressed. Therefore, the material to be heated 30 is appropriately pressurized and is efficiently heated by the high frequency dielectric.

  Air existing between the outer peripheral surface of the inner mold 20 and the inner peripheral surface of the rubber jacket 43 is released from the air vent hole 71 to the outside of the vulcanization molding apparatus 10 by the pressure of the rubber jacket 43. Of course, in the present embodiment, the heat medium may not be supplied into the inner mold 20 and the material to be heated may be heated by high frequency dielectric heating alone. In this case, it is preferable that a secondary material made of a rubber cylinder is provided between the inner mold 20 and the material to be heated 30.

  FIG. 4 shows an electrode material 60 provided on the outer mold 40. The electrode member 60 is provided with the electrode portion 65 having a substantially cylindrical shape as described above, and the flange portion 66 that is connected to the upper end portion of the electrode portion 65 and extends outward. The electrode material 60 is integrally formed of a highly conductive metal such as gold, platinum, silver, aluminum, or copper.

  The electrode portion 65 is provided with a plurality of rectangular slits 75 extending in parallel to the axial direction. The plurality of slits 75 separate the electrode portion 65 in the circumferential direction as a plurality of thin plate portions 76 extending in the axial direction. Has been. Here, each slit 75 extends from a position at a predetermined distance from the upper end of the electrode portion 65 to a position at a predetermined distance from the lower end, and the electrode portion 65 is circumferential in the lower end portion and the upper end portion of the electrode portion. Not separated. In other words, the thin plate portions 76 extending in the axial direction are connected to each other at both ends by an annular fixing portion 77 extending over the entire circumference in the circumferential direction. Here, each thin plate portion 76 is very thin and flexible, and when pressed in the radial direction, the thin plate portion 76 is displaced while being bent in the pressed direction with the fixing portion 77 as a fulcrum.

  The collar portion 66 is provided with a plurality of collar slits 98 extending over the entire radial direction and separating the collar portion 66, and the collar portion 66 is constituted by a plurality of rectangular thin plate portions 99 extending in the radial direction. .

  The lower fixing portion 77 is provided with a support slit 97 that extends in the axial direction of the electrode material 60 and has a width and length shorter than the slit 75. Two or more support slits 97 are provided at equal intervals in the circumferential direction. A protrusion (not shown) whose width is substantially equal to the width of the support slit 97 and whose length in the axial direction is shorter than that of the support slit 97 is provided at a position facing the support slit 97 of the connecting portion 48 (see FIG. 1). ing. The protrusion provided in the connection portion 48 is inserted into the support slit 97, whereby the electrode material 60 cannot be displaced in the circumferential direction, and if the displacement is more than a predetermined amount in the axial direction, the displacement is restricted by the protrusion. Is done. That is, the electrode material 60 is supported by the connection portion 48 so as to be displaceable in the axial direction. Note that the electrode member 60 is not provided with the support slit 97 and may not be supported by the connection portion 48.

  In addition, the thickness of the electrode part 65 and the collar part 66 of the electrode material 60, ie, the thickness of each thin plate part 76, should just be the range which can be deform | transformed by the press of the rubber jacket 43, for example, 0.1-0.5 mm. , Preferably 0.2 mm. Moreover, each slit 75 exhibits the same rectangular shape, is provided at equal intervals, and the width | variety is 1-5 mm, for example, Preferably it is 2 mm. On the other hand, the width of each thin plate portion 76 is, for example, 15 to 25 mm, preferably 20 mm. On the other hand, the width of the flange slit 98 provided in the flange 66 is smaller than the width of the slit 75, and the width of the thin plate portion 99 of the flange 66 is also shorter than the width of the thin plate portion 76 of the electrode portion 65.

  When the electrode material 60 is attached to the vulcanization molding apparatus 10, the fixing portions 77 provided above and below the electrode material 60 are opposed to the inner peripheral surface of the first annular disk 42a and the connection portion 48, respectively. It is provided in the position to do. On the other hand, each thin plate portion 76 is provided at a position facing the rubber jacket 43. Therefore, when the rubber jacket 43 is expanded toward the inside in the radial direction, the fixing portion 77 is not pressed by the rubber jacket 43, while each thin plate portion 76 is pressed by the rubber jacket 43. That is, each thin plate portion 76 is displaced while being deformed radially inward with the fixing portion 77 as a fulcrum, and is brought into close contact with the outer peripheral surface of the heated material 30. The fixing portion 77 of the electrode member 60 is displaced by the deformation of each thin plate portion 76. However, since the lower fixing portion 77 cannot be displaced in the circumferential direction as described above, the electrode member 60 is not torsionally deformed. Absent.

  Note that the fixing portion 77 of the electrode material 60 may be provided at a position facing the rubber jacket 43, similarly to each thin plate portion 76. In this case, each thin plate portion 76 and the fixing portion 77 are displaced while being bent radially inward as the rubber jacket 43 is pressed radially inward, but each thin plate portion 76 is separated by the slit 75. As compared with the fixing portion 77, the bending portion is greatly bent. Therefore, also in this case, the thin plate portion 76 is bent and deformed radially inward with the fixing portion 77 as a fulcrum. That is, the electrode material 60 is configured by the thin plate portions 76 that are relatively deformed relatively to the inside by the pressure from the outer mold 40 and the fixing portions 77 that are relatively deformed.

  When the thin plate portions 76 are displaced while being deformed inward in the radial direction, the electrode portions 65 are reduced in diameter, and the thin plate portions 76 are brought close to each other. Accordingly, the thin plate portions 76 that have been separated before the electrode portion 65 is pressed are in a state of being almost in contact with each other when pressed. That is, almost the entire region of the outer peripheral surface of the auxiliary material 90 is covered with the electrode portion 65.

  With the above configuration, when the electrode portion 65 is pressed by the rubber jacket 43 and the auxiliary material 90 and the material to be heated 30 are narrowed, substantially all the region of the outer peripheral surface of the auxiliary material 90 is in close contact with the electrode portion 65. The inner peripheral surface of the heated material 90 is in close contact with the inner mold 20. Therefore, the auxiliary material 90 and the material to be heated 30 are efficiently heated by high frequency dielectric heating. Further, the thin plate portions 76 divided into a plurality can be easily supplied with electric power from the fixed portion 77 by being connected by the fixed portion 77.

  Further, since the electrode material 60 has flexibility and is deformed to be in close contact with the outer peripheral surface of the auxiliary material 90, the pressing force from the rubber jacket 43 is easily propagated to the heated material 30 and the auxiliary material 90. And since almost all the area | regions of the outer peripheral surface of the auxiliary | assistant material 90 are closely_contact | adhered to the electrode part 65, a pressure is easily urged | biased by the to-be-heated material 30 and the auxiliary | assistant material 90 uniformly.

  In the present embodiment, each slit 75 extending in the axial direction is formed in a rectangular shape. However, the slit 75 may not be formed in a rectangular shape, and the axial direction is such that the width becomes wider toward the central portion of the longitudinal direction. It may be formed in a long oval shape. Further, it may be a slit that extends while being inclined with respect to the axial direction of the electrode material 60, or a slit that extends while meandering in an S shape while being inclined in the axial direction. Furthermore, the slit 75 may meander in a zigzag shape. Further, the collar portion 66 of the present embodiment is provided with a collar portion slit 98 extending in the radial direction and divided into a plurality of portions by the collar portion slit 98, but the collar portion 66 is not provided with a slit, and is integrated. It may be formed as an annular collar.

  The manufacturing method of the electrode material of 1st Embodiment is demonstrated using FIG. As shown in FIG. 5, the electrode material 60 is formed from one metal plate 60A. The metal plate 60A has a flange slit 98 extending from the upper end 60U, and a plurality of thin plate portions 99 divided by the flange slit 98 are formed at the upper end 60U of the metal plate 60A. The metal plate 60A is provided with a plurality of slits 75, and each of the plurality of slits 75 extends from a position separated from the collar slit 98 by a predetermined distance downward to a position above the lower end 60D of the metal plate 60A by a predetermined distance. Extend. The slits 75 are parallel to each other and provided at equal intervals. The metal plate 60A has a left end portion 60L and a right end portion 60R connected to each other and is formed in a cylindrical shape, and each flange slit 98 is bent outward at an angle of approximately 90 °, whereby the metal member 60 is It is formed.

  Next, a second embodiment of the present embodiment will be described with reference to FIG. In the second embodiment, since only the configuration of the electrode material is different from that of the first embodiment, only the configuration of the electrode material will be described below.

  In the second embodiment, the electrode material 260 is formed of a single flexible metal plate, and is provided with a slit 75 as in the first embodiment. Each slit 75 extends from a position at a predetermined distance from the upper end of the electrode member 260 to a position at a predetermined distance from the lower end, and the electrode portion 65 is separated in the circumferential direction at the lower end portion and the upper end portion of the electrode portion. Not. That is, a plurality of thin plate portions 76 extending in the axial direction are formed by the slits 75, and both end portions of the thin plate portion 76 are connected by an annular fixing portion 77 extending over the entire circumference in the circumferential direction.

  The electrode material 260 is wound around the outer peripheral surface of the auxiliary material 90, and thus, like the electrode material 60 of the first embodiment, the electrode material 260 has a cylindrical shape and is disposed concentrically with the heated material 30. Is done. Similarly to the first embodiment, when the electrode material 260 is pressed by the rubber jacket 43, the thin plate portion 76 is bent and deformed radially inward with the fixing portion 77 as a fulcrum, and the outer peripheral surface of the auxiliary material 90. Close contact with.

  In addition, in this modification, the electrode material 260 wound around the outer peripheral surface of the auxiliary material 90 can also adopt other modes as long as a high frequency voltage can be applied to the heated material 30. For example, the electrode material 260 may be a conductive knitted fabric knitted with yarns composed of metal fibers, or a conductive weave woven with warps and wefts composed of metal fibers. It may be a cloth. Further, it may be a thin metal foil such as an aluminum foil, or may be configured by connecting a plurality of orthogonal metal wires. Furthermore, it may be a wire mesh in which metal wires are knitted in a mesh shape.

  Similarly to the electrode material of the first embodiment, when the electrode material 260 configured in this way is pressed by the rubber jacket 43, the electrode material 260 is reduced in diameter radially inward and deformed. Therefore, the electrode material can be brought into close contact with the outer peripheral surface of the auxiliary material 90, and the heated material 30 and the auxiliary material 90 are pinched by the outer mold 40 and the inner mold 20 by the pressing force of the rubber jacket 43. That is, the vulcanization molding apparatus to which these electrode materials 260 are applied is also heated by high-frequency dielectric while pressure is applied, as in the present embodiment.

  A third embodiment according to the present invention will be described with reference to FIG. FIG. 7 shows the configuration of the auxiliary material in the third embodiment of the present invention. In the third embodiment, since the configuration other than the auxiliary material is the same as that of the first embodiment, the description thereof is omitted.

  In the first embodiment, the auxiliary material is composed only of a vulcanized rubber cylinder, but in the third embodiment, the auxiliary material 290 is made of a non-conductive material and is formed in a cylindrical shape. Non-conductive sheets 291 and 292 and a cylindrical vulcanized rubber cylinder 293. The first non-conductive sheet 291 is disposed on the inner peripheral side, the second non-conductive sheet 292 is disposed on the outer peripheral side, and the vulcanized rubber cylinder 293 is sandwiched between these non-conductive sheets 291 and 292. Provided. With such a configuration, the auxiliary material 290 can insulate between the electrode portion 65 (see FIG. 3) and the inner mold 20. Therefore, in the third embodiment, even when a high frequency voltage is applied between both electrodes, no spark is generated between the electrodes.

The first and second non-conductive sheets 291 and 292 are made of non-conductive resin such as fluororesin, for example, polytetrafluoroethylene sheet. On the other hand, the vulcanized rubber cylinder 293 in the third embodiment may have a configuration similar to that of the vulcanized rubber cylinder of the first embodiment and may be non-conductive, but is preferably conductive. . This is because the dielectric efficiency of the high frequency dielectric can be increased by making the vulcanized rubber cylinder 293 conductive. When the vulcanized rubber cylinder 293 is conductive, the volume resistivity value is 1 × 10 ³ Ω · cm to 1 × 10 ⁷ Ω · cm. Therefore, the rubber component of the vulcanized rubber cylinder 293 is the same as that of the first embodiment, but as a main reinforcing agent blended in the rubber component, it is better to blend carbon black. 20-60 parts by weight is blended with 100 parts by weight of the rubber component.

  The auxiliary material 290 includes a vulcanized rubber cylinder 293 having a relatively low elastic modulus and non-conductive sheets 291 and 292 having a relatively high elastic modulus. The non-conductive sheets 291 and 292 are vulcanized rubber cylinders 293. Therefore, even in the second embodiment, when the heated material 30 (see FIG. 3) is sandwiched, the auxiliary material 290 can be in close contact with the heated material 30.

  A fourth embodiment according to the present invention will be described with reference to FIGS. In the first embodiment, the electrode material is disposed outside the outer peripheral surface of the material to be heated, and pressure is applied from the outside to the inside of the material to be heated, but in this embodiment, The electrode material is disposed inside the inner peripheral surface of the material to be heated, and pressure is applied from the inside to the outside of the material to be heated. In addition, the auxiliary material is arranged on the inner side in the radial direction of the material to be heated. Hereinafter, the fourth embodiment will be described focusing on differences from the first embodiment.

  8 and 9 show a vulcanization molding apparatus 100 according to the fourth embodiment. The vulcanization molding apparatus 100 includes an inner mold 120 and an outer mold 140 for housing the inner mold 120 therein. The inner mold 120 is formed in a substantially cylindrical shape concentrically with the upper mold 122 having a disk shape, a lower mold 123 having a disk shape and facing the upper mold 122, and the upper mold 122 and the lower mold 123. The rubber jacket 143 is provided. Here, the rubber jacket 143 is connected to the upper mold 122 and the lower mold 123. The inner mold 120 is formed in a substantially cylindrical shape having the upper mold 122 and the lower mold 123 as upper and lower surfaces, and the rubber jacket 143 and the side surfaces of the upper mold 122 and the lower mold 123 as outer peripheral surfaces. The upper mold 122 and the lower mold 123 are connected by a column 128, and the column 128 supports the upper mold 122 and the lower mold 123.

  On the lower surface of the upper mold 122, an annular bottom projection 156 that protrudes downward is provided over the entire outer periphery. On the upper surface of the lower mold 123, an annular upper surface protruding portion 157 that protrudes upward is provided over the entire outer periphery. The rubber jacket 143 has a cylindrical shape, and is contracted so that both ends of the cylindrical shape are reduced in diameter, whereby the rubber jacket 143 is engaged with the inner peripheral side surfaces of the bottom surface protruding portion 156 and the top surface protruding portion 157, and the upper mold 122 and It is fixed to the lower mold 123.

  A sealed space 198 is provided on the radially inner side of the rubber jacket 143, and a pressure medium is supplied to the sealed space 198. When the pressure medium is supplied, the sealed space 198 presses the entire rubber jacket 143 toward the outside in the radial direction. Similarly to the first embodiment, the upper mold 122 and the lower mold 123 of the inner mold 120 are provided with inlet / outlet pipes 124 and 125. The inlet / outlet pipe 124 supplies a pressure medium to the sealed space 198, and the inlet / outlet pipe 125. Discharges the pressure medium from the enclosed space 198. Compressed air is used as the pressure medium.

  A cylindrical electrode member 160 is provided on the radially outer side of the rubber jacket 143 (that is, the inner mold 120). The electrode material 160 is provided along the outer peripheral surface of the inner mold 120 (that is, the rubber jacket 143), and an upper portion thereof is fixed to a side surface of the upper mold 122. An auxiliary material 190 is surrounded on the outer peripheral surface of the electrode material 160. The auxiliary material 190 is composed of only a cylindrical vulcanized rubber cylinder as in the first embodiment. The heated material 130 is further wound around the outer peripheral surface of the auxiliary material 190, and the wound heated material 130 has a substantially cylindrical shape as in the first embodiment.

  The outer mold 140 includes a storage chamber 167 having a substantially cylindrical shape with a bottom, and a heating unit 149 for heating the inner peripheral surface 168 of the storage chamber 167. The bottom surface 147 of the storage chamber 167 is provided with a substantially circular insertion hole 146 at the center, and a connection pipe 185 for discharging the pressure medium from the inner mold 120 is inserted into the insertion hole 146. Note that second and third insulating blocks 161b and 161c are provided on the bottom surface 147 in the same manner as in the first embodiment.

  The heating unit 149 is provided so as to surround the outer peripheral surface of the storage chamber 167 of the outer mold 140, and a heating medium is supplied to the heating unit 149, and the inner peripheral surface 168 of the storage chamber 167 is caused by the heating medium. It is warmed. The heat medium is injected from the injection port 152 provided in the outer mold 140 and discharged from the discharge port 153.

  FIG. 9 shows a vulcanization molding apparatus when the inner mold 120 is housed in the outer mold 140. As shown in FIG. 9, when the inner mold 120 to which the heated material 130 is attached is stored in the storage chamber 167, the lower mold 123 of the inner mold 20 and the lower surface of the auxiliary material 190 are the second insulating block 161b. In addition, the lower surface of the material to be heated 130 is disposed close to or in contact with the upper surface of the third insulating block 161c. In addition, the inner diameter of the storage chamber 167 is slightly larger than the outer diameter of the heated material 130, and when the inner mold 120 is stored in the outer mold 140, the outer peripheral surface of the heated material 130 is the inner peripheral surface of the storage chamber 167. 168 is provided. As in the first embodiment, an annular upper lid 195 having an L-shaped cross section is placed above the inner mold 120, and the heated material 130 and the auxiliary material 190 are moved upward by the upper lid 195. Jumping out is prevented.

  When the inner mold 120 is stored in the storage chamber 167, conductive wires (not shown) are connected to the inner mold 120 and the outer mold 140, respectively. Here, the inner mold 120 is electrically connected to the electrode material 160 via an upper mold 122 and a lower mold 123 to which the electrode material 160 is attached. Therefore, a high frequency voltage can be applied between the electrode material 160 and the outer mold 140.

  In addition, connecting pipes 185 are connected to the inlet / outlet pipes 124 and 125 of the inner mold 120 in order to supply a pressure medium. The connecting pipe 185 is made of an insulator such as silicon so that the current supplied from the inner mold 120 is not conducted. Air pressure is used as the pressure medium supplied to the inner mold 120.

  Next, the heating / vulcanizing method in this embodiment will be described. In the present embodiment, in a state where the inner mold 120 is housed in the outer mold 140, a pressure medium is supplied to the sealed space 198 provided in the inner mold 120, whereby the rubber jacket 143 expands outward. Then, the electrode material 160 is pressed. When the cylindrical electrode member 160 is pressed outward in the radial direction, it is deformed by bending and deforming as will be described later, closely contacts the inner peripheral surface of the auxiliary material 190, and presses the auxiliary material 190. Thus, the heated material 130 and the auxiliary material 190 are sandwiched between the electrode material 160 and the inner peripheral surface 168 of the outer mold, and a predetermined pressure is urged. In addition, a high frequency voltage is applied between the electrode material 160 and the outer mold 140, whereby the heated material 130 and the auxiliary material 190 are heated by the high frequency dielectric.

  Since the inner mold 120, the outer mold 140, and the electrode material 160 are made of metal, they have high thermal conductivity and easily absorb thermal energy. However, in the present embodiment, the inner peripheral surface of the outer mold 140 is heated by the heating unit 149. Therefore, the material to be heated 130 heated by the high frequency dielectric is hardly absorbed by the outer mold 140. Further, a secondary material 190 made of a rubber cylinder having a low thermal conductivity is provided between the inner mold 120 and the material 130 to be heated. Therefore, the auxiliary material 190 heated by the high frequency dielectric is absorbed by the inner mold 120 and the electrode material 160, but the heated material 130 is also absorbed by the inner mold 120 and the electrode material 160 due to the heat insulating effect of the auxiliary material 190. There is almost no. Furthermore, the upper part and the lower part of the heated material 130 are thermally insulated by the upper lid 195, the second insulating block 161b, and the like. Therefore, any part of the material to be heated 130 is heated uniformly.

  In addition, since air pressure is used as the pressure medium supplied into the inner mold 120, the pressure medium is contained in the storage chamber 167 due to the tearing of the rubber jacket 143 and insufficient sealing of the fixing portion between the inner mold 120 and the rubber jacket 143. Even if leaked, the leaked pressure medium does not cause a spark and explosive rupture of the heated material 130.

  10 to 11 show the electrode material 160 provided on the inner mold 120. FIG. 10 shows the electrode material 160 provided on the inner mold 120. FIG. 11 schematically shows a connecting portion between the thin plate 176 and the fixing portion 177. In the electrode material 160 in the second embodiment, a plurality of thin plates 176 are arranged in an interdigital manner so that adjacent thin plates 176 overlap each other in the circumferential direction, and the aggregate of the plurality of thin plates 176 has a cylindrical shape. An electrode material 160 is formed. The thin plate 176 is fixed at its upper end and lower end to a fixing portion 177 formed in an annular plate shape on the circumferential surface on which each thin plate portion 176 is arranged. Are connected by a fixing portion 177. As shown in FIG. 11, the thin plate portions 176 are alternately fixed to the inner peripheral surface and the outer peripheral surface of the annular plate-shaped fixing portion 177.

  In the electrode material 160, the upper end portion of the electrode material 160 is fixed to the side surface of the upper die 122, and the upper and lower fixing portions 177 of the electrode material 160 are provided at positions facing the side surfaces of the upper die and the lower die, respectively. In addition, each thin plate portion 176 is provided at a position facing the rubber jacket 143. Accordingly, when the rubber jacket 143 is expanded outward, the fixing portion 177 is not pressed by the rubber jacket 143, while each thin plate portion 176 is pressed by the rubber jacket 143. In other words, each thin plate portion 176 is displaced while being bent and deformed radially outward with the fixing portion 177 as a fulcrum, and is brought into close contact with the inner peripheral surface of the auxiliary material 190. The fixing portion 177 on the lower end side of the electrode material 160 may be movably supported on the outer peripheral surface of the lower mold 123 as in the first embodiment, or may not be supported.

  The thin plate portions 176 that overlap each other in the circumferential direction are pressed by the rubber jacket 143 and displaced while being deformed radially outward, and the thin plate portions 176 are separated. Accordingly, the thin plate portions 176 are separated from each other and the side surfaces thereof are in contact with each other. That is, almost the entire region of the outer peripheral surface of the heated material 130 is covered with the electrode material 160.

  With the above configuration, the auxiliary material 190 and the material to be heated 130 are in close contact with the inner peripheral surfaces of the electrode part 160 and the outer mold 140, so that an appropriate pressure is applied to the auxiliary material 190 and the material to be heated 130. It is heated efficiently by high frequency dielectric heating.

  FIG. 12 shows a modification of the electrode material in the fourth embodiment. In the present embodiment, each thin plate portion 176 is formed in a rectangular shape. However, in this modified example, each thin plate portion 176 is formed in an elliptical shape so as to become wider toward the central portion in the longitudinal direction. The When formed in this way, adjacent thin plate portions 176 overlap each other at the center of the thin plate portion 176, but adjacent thin plate portions 176 do not overlap at both ends. Therefore, in the fourth embodiment, both end portions of each thin plate portion 176 are alternately fixed to the inner peripheral surface and the outer peripheral surface of the annular fixing portion 177, but in this modification, each thin plate portion 176 is As shown in FIG. 12, it can be fixed only to the outer peripheral surface.

  In the first and second embodiments, each thin plate portion is connected to a fixed portion and connected to the fixed portion. However, each thin plate portion is directly connected to an outer mold or an inner mold. It may be connected by an inner mold. In this case, when each thin plate portion is pressed in the radial direction, the thin plate portion is deformed while being bent in the radial direction with the outer mold or the inner mold as a fulcrum.

Further, the inner mold 20 of the first embodiment is formed in a columnar shape, and the outer peripheral surface 27 is formed in a cylindrical surface shape. However, the shape of the outer peripheral surface 27 can be changed as appropriate. In order to mold the belt, concave portions and convex portions may be provided alternately in the circumferential direction. That is, the outer peripheral surface 27 of the first embodiment is a circumferential surface, but the circumferential surface may not be configured with an accurate circumference. Similarly, the inner peripheral surface of the storage chamber 167 of the fourth embodiment is also formed on a circumferential surface, and the shape of this inner peripheral surface can also be selected as appropriate, for example, a concave portion and a convex portion in the circumferential direction. May be provided alternately. That is, the outer peripheral inner surface 168 of the second embodiment is a circumferential surface, but the circumferential surface may not be configured with an accurate circumference. In this specification, a conductive substance means a volume specific resistance value of less than 1 × 10 ⁸ Ω · cm, and a non-conductive substance means a volume specific resistance value of 1 × 10 ⁸ Ω · cm or more.

  Hereinafter, the present invention will be specifically described with reference to examples. However, the present invention is not limited to the examples described below.

[Example 1]
In Example 1, a flat belt was manufactured using the vulcanization molding apparatus according to the first embodiment. In Example 1, a canvas and an unvulcanized rubber sheet were sequentially wound around a cylindrical inner mold having a diameter of 130 mm, and an unmolded belt sleeve was provided on the outer peripheral surface of the inner mold. The canvas is a bag-woven fabric woven with nylon fibers. The canvas is dipped in a rubber paste containing conductive carbon black and chloroprene rubber blended as shown in Table 1, and then dried by heating and impregnation treatment. Was given. As the unvulcanized rubber sheet, the one shown in Table 1 was used, and its thickness was 8 mm.

  The electrode material shown in FIG. 4 was used as the electrode material. The electrode part had a cylindrical shape with a diameter of 160 mm and an axial length of 50 cm, and its thickness was 0.2 mm. The electrode part of the electrode material was provided with a slit having a width of 2 mm extending in the axial direction. The interval between adjacent slits, that is, the width of the thin plate portion was 20 mm. In order to measure the temperature of the unvulcanized rubber sheet, after being wound around the inner mold, a thermometer is installed in the middle part in the thickness direction, the outermost part on the outer peripheral surface side, and the innermost part on the inner peripheral surface side. Inserted.

A secondary material made of a rubber cylinder was disposed inside the electrode portion in the radial direction (see FIG. 3). The auxiliary material had a radial thickness of 7 mm and an inner diameter of 145 mm. In the rubber compounding of the rubber cylinder of Example 1, silica was used as the main reinforcing material as shown in Table 2.

  After inserting the inner mold with the unmolded belt sleeve into the outer mold, a high frequency voltage was applied between the electrode portion and the inner mold. Simultaneously with the application of the high-frequency voltage, water at 150 ° C. and 4.7 atm was supplied into the inner mold to raise the temperature of the outer peripheral surface of the inner mold. Compressed air at normal temperature (about 20 ° C) is supplied into the outer mold, the rubber jacket is expanded by air pressure of 9.9 atmospheres, and the auxiliary material and the unmolded belt sleeve are sandwiched between the outer mold and the inner mold. did.

  By the high frequency dielectric heating, the intermediate part, the outermost part, and the innermost part of the unmolded belt sleeve all reached 160 ° C. after 5 minutes. Thereafter, the application of the high-frequency voltage was stopped, the supply of water vapor to the inner mold was continued, and the unmolded belt sleeve was heated for 12 minutes. During heating for 12 minutes, the temperature of the middle part, the outermost part, and the innermost part of the green belt sleeve was maintained at 160 ° C. After the heating, cooling water was supplied to the inside of the inner mold to cool the inner mold and the belt sleeve, and then the inner mold was taken out from the outer mold to obtain a vulcanized belt slab. The belt slab was polished and then cut in the width direction to form a molded belt.

[Example 2]
In Example 2, the vulcanization molding apparatus of the second embodiment was used, and aluminum foil was used as the electrode material. In Example 2, a 35 mm thick unvulcanized rubber sleeve having a rubber composition shown in Table 3 was wound around a cylindrical inner mold having a diameter of 130 mm as a material to be heated. The auxiliary material had an inner diameter of 170 mm and a thickness of 7 mm, and an electrode material was wound around the outer peripheral surface of the auxiliary material. The rubber composition of the auxiliary material is as shown in Table 2. In addition, the volume specific resistance value of the auxiliary materials of Examples 1 and 2 was 1 × 10 ⁸ Ω · cm or more, for example.

  After inserting the inner mold with the material to be heated into the outer mold, a high frequency voltage is applied between the electrode material (aluminum foil) and the inner mold, and at the same time as the application of the high frequency voltage, .7 atm of water vapor was supplied to increase the temperature of the outer peripheral surface of the inner mold. Inside the outer mold, air at normal temperature (about 20 ° C.) was supplied, the rubber jacket was expanded by air pressure of 9.9 atmospheres, and the auxiliary material and the unmolded belt sleeve were pinched by the outer mold and the inner mold. .

  By application of the high frequency voltage and supply of water vapor to the inner mold and the outer mold, the intermediate part, outermost part, and innermost part of the heated material all reached 160 ° C. after 5 minutes. Thereafter, the application of the high-frequency voltage was stopped, the supply of water vapor to the inner mold was continued, and the heated material was heated for 15 minutes. During the heating for 15 minutes, the temperature of the middle part, the outermost part, and the innermost part of the heated material was maintained at 160 ° C. After the heating, cooling water was supplied to the inside of the inner mold to cool the inner mold, the auxiliary material and the material to be heated, and then the inner mold was taken out from the outer mold to obtain a vulcanized rubber packing slab. The rubber packing slab is appropriately cut and formed into a rubber packing.

[Comparative Example 1]
Comparative Example 1 was an example in which an unvulcanized rubber sleeve was vulcanized and molded without providing auxiliary materials. In Comparative Example 1, a belt slab was produced in the same manner as in Example 1 except that no auxiliary material was provided. In Comparative Example 1, an outer mold having a small diameter corresponding to the thickness at which the auxiliary material is not provided was used.

  In Comparative Example 1, as in Example 1, after inserting the inner mold with the unmolded belt sleeve into the outer mold, a high frequency voltage was applied between the electrode portion and the inner mold. Simultaneously with the application of the high-frequency voltage, water at 150 ° C. and 4.7 atm was supplied into the inner mold to raise the temperature of the outer peripheral surface of the inner mold. Normal temperature (about 20 ° C.) air was supplied into the outer mold, the rubber jacket was inflated by air pressure of 9.9 atmospheres, and the unmolded belt sleeve was pinched by the outer mold and the inner mold.

  Due to the application of the high frequency voltage and the supply of water vapor to the inner mold, the intermediate part, outermost part, and innermost part of the unmolded belt sleeve reached 155, 130, and 160 ° C. after 5 minutes, respectively. Thereafter, the application of the high-frequency voltage was stopped, and heating was continued for 12 minutes while the supply of water vapor to the inner mold was continued. After the heating, cooling water was supplied to the inside of the inner mold to cool the inner mold and the belt sleeve, and then the inner mold was taken out from the outer mold to obtain a vulcanized belt slab.

[Comparative Example 2]
In Comparative Example 2, a flat belt was manufactured using a conventional vulcanization molding apparatus. In the vulcanization molding apparatus of Comparative Example 2, the electrode material and the auxiliary material were not provided, and the unmolded belt sleeve was heated by the steam supplied into the outer mold and the inner mold. Also in the comparative example, an inner mold fitted with an unmolded belt sleeve having the same configuration as in Example 1 was inserted into the outer mold, and the unmolded belt sleeve was vulcanized.

  In the vulcanization molding of the unmolded belt sleeve, steam at 150 ° C. and 4.7 atm was supplied into the inner mold to raise the temperature of the outer peripheral surface of the inner mold. Further, steam at 180 ° C. and 9.9 atm was supplied into the outer mold, the rubber jacket was expanded by the steam pressure, and the unmolded belt sleeve was clamped between the outer mold and the inner mold. While maintaining this pinched state, the unmolded belt sleeve was heated for 30 minutes with water vapor supplied to the inner mold and the outer mold. The intermediate part, outermost part and innermost temperature after heating for 30 minutes were 140 ° C., 165 ° C. and 160 ° C., respectively. After the heating, cooling water was supplied into the inner mold to cool the inner mold and the belt sleeve, and then the inner mold was taken out from the outer mold to obtain a vulcanized belt slab.

[Comparative Example 3]
In Comparative Example 3, the high-frequency dielectric heating apparatus was not provided with electrode materials and auxiliary materials, and the material to be heated was vulcanized without using high-frequency dielectric heating. For the material to be heated, an unvulcanized sleeve made of the same rubber layer as in Example 2 was used. In the vulcanization molding of the material to be heated, water vapor of 150 ° C. and 4.7 atm was supplied into the inner mold to raise the temperature of the outer peripheral surface of the inner mold. Further, 180 ° C. and 9.9 atm water vapor was similarly supplied into the outer mold, the rubber jacket was expanded by the water vapor pressure, and the material to be heated was sandwiched between the outer mold and the inner mold. The material to be heated was heated for 75 minutes with water vapor supplied to the inner mold and the outer mold while maintaining this sandwiched state. The intermediate part, outermost part, and innermost temperature after heating for 75 minutes were 140 ° C., 160 ° C., and 155 ° C., respectively. After heating for 75 minutes, cooling water was supplied into the inner mold to cool the inner mold and the material to be heated, and then the inner mold was taken out of the outer mold to obtain a vulcanized rubber packing slab.

[Comparative Example 4]
In Comparative Example 4, the same procedure as in Example 1 was performed except for the rubber compounding of the auxiliary material. As shown in Table 2, the rubber composition of the auxiliary material of Comparative Example 4 was an example using carbon black as the main reinforcing material. And the volume resistivity value of the auxiliary material was 1 × 10 ³ Ω · cm. In Comparative Example 4, as in Example 1, when a high frequency voltage was applied between the electrode portion and the inner mold, sparks were generated between both electrodes, and the material to be heated could not be stably heated. That is, it can be understood that when the secondary material is composed of a single rubber layer, if the rubber layer is conductive, sparks are generated by a high-frequency high voltage, and therefore the secondary material should be non-conductive.

[Evaluation method of belt slab and rubber packing slab]
The obtained belt slabs and rubber packing slabs of Examples 1 and 2 and Comparative Examples 1 to 3 were evaluated by a pico abrasion test. The pico abrasion test was performed according to JISK6264. Specifically, the thickness obtained by slicing the vulcanized rubber layer of the belt slab (rubber packing slab) along the circumferential direction and taking out from the outermost layer, the intermediate layer, and the innermost layer on the inner circumferential side of the rubber layer A disk-shaped test piece having a diameter of 2 mm and a diameter of 25 mm was obtained. These test pieces were worn according to the method described in JISK6264, and the amount of wear was measured. Table 4 shows the amount of wear in the pico wear test. In addition, it shows that the intensity | strength of each layer and a vulcanization degree (progression degree of vulcanization) are so high that there is little abrasion amount of each test piece in a pico abrasion test.

  As shown in Table 4, in Comparative Examples 2 and 3, the wear amount of the intermediate layer was larger than the wear amount of the outermost layer and the innermost layer. This is because vulcanization of the outermost layer and innermost layer has progressed sufficiently, but the intermediate layer is insufficiently vulcanized. That is, in Comparative Examples 2 and 3, it can be understood that sufficient heat energy is not applied to the intermediate layer, and the vulcanization degree and strength of each layer are non-uniform.

  On the other hand, in Examples 1 and 2, it can be understood that the wear amounts of the outermost layer, the intermediate layer, and the innermost layer are substantially the same. That is, it can be understood that the material to be heated heated by the high frequency dielectric heating device of the present invention is given uniform thermal energy to each layer, and the vulcanization degree of each layer becomes uniform.

  In addition, as shown in Comparative Example 1, when high-frequency dielectric heating was performed without using the auxiliary material, the wear amount of the intermediate layer and the innermost layer of the non-heating material was relatively low and substantially the same, The amount of wear on the outermost layer was relatively high. That is, in Comparative Example 1, since no auxiliary material was used, it can be understood that the outer peripheral surface of the heated material was not sufficiently vulcanized.

  As described above, in this embodiment, by providing the auxiliary material, the material to be heated can be uniformly heated without supplying the heating medium into the outer mold. Further, a material to be heated having a large thickness as in Example 2 can be heated uniformly.

It is sectional drawing of the inner type | mold and outer type | mold of the vulcanization molding apparatus which concerns on 1st Embodiment. It is typical sectional drawing of a to-be-heated material. It is sectional drawing which shows a vulcanization molding apparatus when an inner type | mold is inserted in an outer type | mold. It is a perspective view which shows the electrode material which concerns on 1st Embodiment. It is a top view which shows the electrode material which concerns on 1st Embodiment. It is a perspective view which shows the electrode material which concerns on 2nd Embodiment. It is sectional drawing of the auxiliary material which concerns on 3rd Embodiment. It is sectional drawing of the inner type | mold and outer type | mold of the vulcanization molding apparatus which concerns on 4th Embodiment. In 4th Embodiment, it is sectional drawing which shows a vulcanization molding apparatus when an inner type | mold is inserted in an outer type | mold. It is a perspective view which shows the electrode material which concerns on 4th Embodiment. It is a top view when the electrode material which concerns on 4th Embodiment is seen from upper direction. It is a perspective view which shows the modification of the electrode material which concerns on 4th Embodiment.

Explanation of symbols

10, 100 Vulcanization molding equipment 20 Inner mold (first electrode)
27 Outer peripheral surface 30, 130 Heated material 40 Outer mold 43, 143 Rubber jacket 54, 198 Sealed space 60 Electrode material (second electrode)
67,167 Storage chamber 65 Electrode part 66 Gutter part 75 Slit 76 Thin plate part 77, 177 Fixing part 90, 190 Secondary material 120 Inner mold 140 Outer mold (second electrode)
160 Electrode material (first electrode)
176 Thin plate (thin plate part)

Claims (14)

A high-frequency dielectric heating apparatus for applying a high-frequency voltage to a material to be heated formed in a cylindrical shape and heating it by high-frequency dielectric,
A first electrode and a second electrode arranged on the inner peripheral surface side and the outer peripheral surface side of the heated material, respectively, for applying a high frequency voltage in the thickness direction of the heated material;
Between at least one of the first and second electrodes and the material to be heated, the material to be heated is disposed along an inner peripheral surface or an outer peripheral surface of the material to be heated. A high-frequency dielectric heating apparatus comprising: a secondary material including a cylindrical vulcanized rubber body for maintaining heat. A columnar inner mold on which the heated material is mounted on the outer peripheral surface;
An outer mold disposed so as to surround the inner mold on which the heated material is mounted,
Either one of the first and second electrodes is disposed between one of the inner mold and the outer mold and the material to be heated, and has a cylindrical shape.
The high-frequency dielectric heating device according to claim 1, wherein the auxiliary material is disposed between one electrode having the cylindrical shape and the material to be heated.   The second electrode is one electrode having the cylindrical shape, and is disposed between the outer mold and the material to be heated, and the material to be heated includes the second electrode and the auxiliary material. The high-frequency dielectric heating device according to claim 2, wherein the high-frequency dielectric heating device is pressed by an outer mold and sandwiched between the outer mold and the inner mold.   4. The high frequency dielectric heating according to claim 3, wherein when the second electrode is pressed from the outer mold, at least a part of the second electrode is bent and deformed inward to press the auxiliary material. 5. apparatus.   The high-frequency dielectric heating apparatus according to claim 3, wherein the outer mold includes a jacket that presses the second electrode by expanding inward.   The high frequency dielectric heating device according to claim 3, wherein the inner mold has an outer peripheral surface made of metal and serves as a first electrode.   The high frequency dielectric heating apparatus according to claim 6, wherein the outer peripheral surface of the inner mold is heated by a heat medium different from the heating by the high frequency voltage. An electrode disposed between one of the inner mold and the outer mold and the material to be heated includes a plurality of thin plate portions having flexibility separated in a circumferential direction, and the plurality of thin plate portions. A fixing portion connected in the circumferential direction,
The plurality of thin plate portions are respectively deformed inward toward the material to be heated, so that each thin plate portion is disposed along the outer peripheral surface of the material to be heated. 2. A high frequency dielectric heating apparatus according to 2.   The first electrode is one electrode having the cylindrical shape, and is disposed between the inner mold and the heated material, and the heated material includes the first electrode and the auxiliary material. The high-frequency dielectric heating device according to claim 2, wherein the high-frequency dielectric heating device is pressed by the inner mold and sandwiched between the outer mold and the inner mold.   10. The high frequency dielectric heating device according to claim 9, wherein when the first electrode is pressed from the inner mold, at least a part of the first electrode is bent and deformed outward to press the auxiliary material. .   The high-frequency dielectric heating device according to claim 9, wherein the inner mold includes a jacket that presses the first electrode by expanding toward the outside.   The high-frequency dielectric heating device according to claim 5, wherein the jacket is expanded by air pressure.   The high frequency dielectric heating apparatus according to claim 1, wherein the auxiliary material electrically insulates between the one of the electrodes and the material to be heated.   First and second electrodes for applying a high-frequency voltage to the heated material are disposed on the inner peripheral surface side and the outer peripheral surface side of the heated material formed in a cylindrical shape, respectively. A cylindrical shape for keeping the material to be heated between at least one of the two electrodes and the material to be heated along the inner peripheral surface or the outer peripheral surface of the material to be heated. Manufacture for manufacturing a heated material to be heated by arranging a secondary material including a vulcanized rubber body, applying a high frequency voltage in the thickness direction of the material to be heated, and heating the material to be heated by high frequency dielectric. Method.

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