JP3482599B2 - Dielectric heating mold for rubber bearing - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dielectric heating mold for manufacturing a rubber bearing having a rectangular shape in plan view. The rubber bearing is a bearing that is a rubber-metal laminated body installed between the bridge girder and the bridge pier, and has the ability to follow the expansion and contraction with respect to the bridge girder and also have the ability to protect the bridge pier from an earthquake.

[0002]

2. Description of the Related Art A rubber bearing is basically manufactured by alternately stacking steel plates and elastomer plates in a mold and accommodating them, and pressing the mold with a press machine while heating the mold with a hot platen. ing. Specifically, the laminated rubber is heated to the rubber flow temperature, and the laminated rubber is molded by the pressing pressure to suppress the thermal expansion of the laminated rubber in the vertical direction to secure the product size, and to vulcanize the rubber in a constantly pressurized state. It is manufactured by a process of vulcanizing and adhering a steel plate to rubber.

However, since the elastomer plate constituting the rubber bearing has a small thermal conductivity, the temperature rising rate is different between the portion close to the heat source and the portion remote from the heat source, and therefore uneven vulcanization progresses. There is a problem in that the physical properties of the laminated rubber (vertical elastic modulus, shear elastic modulus, adhesive force between the elastomer plate and the steel plate, etc.) vary.

Therefore, it is conceivable to accommodate a laminated body formed by alternately laminating a plurality of elastomer plates and steel plates in a molding die and integrate the laminated body by dielectric heating to manufacture a rubber bearing. At present, there is no dielectric heating mold for manufacturing such a rubber bearing.

Incidentally, this type of dielectric heating mold is relatively inexpensive and can withstand long-term use.
It is an essential condition that all the elastomer plates are heated substantially uniformly.

[0006]

Therefore, according to the present invention, a dielectric heating mold for rubber bearings, which is relatively inexpensive, can withstand long-term use, and in which all elastomer plates are heated substantially uniformly. The challenge is to provide.

[0007]

(Invention of Claim 1) The dielectric heat-forming die for rubber bearing according to the present invention is formed by alternately laminating a plurality of rectangular elastomer plates and conductive metal plates. A molding die used when performing dielectric heating integration using a frequency voltage of 1 to 300 MHz in a mode in which pressure is applied in the stacking direction at least for a period of time, and a plurality of separate flat plates are combined in a rectangular shape. And a conductive upper and lower molds that retain the frame shapes of the upper and lower ends of the frame mold. (Invention of Claim 2) The dielectric heating molding die for rubber bearing according to the present invention relates to the invention of claim 1, wherein the frame die independently maintains the frame shape.
A plurality of flat plates are joined by a fastening member. (Invention of Claim 3) The dielectric heating molding die for rubber bearing according to the present invention relates to the invention of claim 1 or 2, wherein the flat plate constituting the frame die is impregnated with resin in a cloth made of fibrous reinforcement. A plurality of the above-mentioned products are laminated and heated and pressurized to be integrated. (Invention of Claim 4) The dielectric heat-molding die for rubber bearing according to the present invention relates to the invention of Claim 3, wherein the resin forming the flat plate is an epoxy resin or an ester resin. (Invention of Claim 5) The dielectric heating mold for rubber bearing according to the present invention relates to the invention of any one of claims 1 to 4, wherein the flat plate has a dielectric loss coefficient of the value of the dielectric loss coefficient of the elastomer plate. It is the following. (Invention according to claim 6) In the dielectric heat molding die for rubber bearing according to the present invention, a laminated body formed by alternately laminating a plurality of rectangular elastomer plates and conductive metal plates is pressed at least temporarily in the laminating direction. A molding die used when performing dielectric heating integration using a frequency voltage of 1 to 300 MHz in a mode of applying a non-conductive frame die having a square inner peripheral surface manufactured as one body, And a conductive upper and lower molds that retain the frame shapes of the upper and lower ends of the frame mold. (Invention according to claim 7) The dielectric heating molding die for rubber bearing according to the present invention relates to the invention according to claim 6, wherein the frame is formed by laminating resin impregnated cloth in multiple stages by a hand lay-up method. It is a thing. (Invention of Claim 8) The dielectric heating molding die for rubber bearing according to the present invention relates to the invention of Claim 7, wherein the resin forming the frame die is an epoxy resin or an ester resin. (Invention of Claim 9) The dielectric heat-molding die for rubber bearing according to the present invention relates to the invention of claim 6, wherein the frame die is a liquid rubber or a thermoplastic material mixed with a fibrous reinforcement. It is a thing. (Invention of Claim 10) The dielectric heating mold for rubber bearing according to the present invention relates to the invention of Claim 1 or 6, wherein the upper and lower molds are formed with grooves corresponding to the frame shapes of the upper and lower ends of the frame mold. The upper and lower ends of the frame die are fitted in the upper and lower die grooves. (Invention of Claim 11) The dielectric heating molding die for rubber bearing according to the present invention relates to the invention of claim 1 or 6, and is a molding die intended for a laminate having through holes in the laminating direction, A non-conductive core is provided which penetrates the through hole of the laminate. (Invention of Claim 12) The dielectric heat-molding die for rubber bearing according to the present invention is claimed in Claim 11.
Regarding the described invention, the resin constituting the core is an epoxy resin or an ester resin. (Invention of Claim 13) The dielectric heat-molding die for rubber bearing according to this invention is defined by Claim 11.
Or in the invention described in 12, the dielectric loss coefficient of the core is equal to or less than the value of the dielectric loss coefficient of the elastomer plate.

The function of the dielectric heating mold for bearing the rubber in the above-mentioned invention will be described in the section of the following embodiments of the invention.

[0009]

DETAILED DESCRIPTION OF THE INVENTION The present invention will be described below with reference to the drawings showing the embodiments.

FIG. 1 shows an apparatus for manufacturing a rubber bearing using a dielectric heating method from a laminated body S having upper and lower flange plates 7 made of steel.

In this manufacturing apparatus, as shown in FIG. 2, a laminated body S is placed in an internal space K of a dielectric heating mold SK formed by upper and lower molds 1 and 2, a rectangular frame mold 3 and a core 4. The upper and lower molds 1 and 2 are housed by a press machine while applying a high frequency voltage generated by a high frequency oscillator 9 as shown in FIG. 1 between the upper and lower molds 1 and 2 via parallel electrode plates P1 and P2. The pressure is applied to the laminated body S by applying pressure in the direction of approaching.

The main components and the like employed in this rubber bearing manufacturing apparatus will be described in detail below. [Regarding Laminate S] As shown in FIG.
Alternately laminating a rectangular elastomer plate 5 having holes 50 and a rectangular steel plate 6 having holes 60 (corresponding to the conductive metal plate described in the column of means for solving the problem), The flange plate 7 having holes 70 is arranged above and below the structure. An adhesive layer (for example, a combination of a phenol-based polymer and a chlorine-based polymer) may be interposed between the elastomer plate 5 and the steel plate 6 and between the elastomer plate 5 and the flange plate 7. preferable. Also,
Natural rubber and synthetic rubber are used as the elastomer plate 5, but instead of the elastomer plate 5, a diene-based elastomer, a non-diene-based elastomer, a thermoplastic elastomer,
Liquid rubber and other moldable polymers can be used. [High-frequency oscillator 9] The high-frequency oscillator 9 is composed of a known circuit. The frequency used for high frequency dielectric heating is 13.6 MHz, but 1 to 30
It can be used in the range of 0 MHz, preferably 4
The range is -80 MHz. [Regarding Upper Mold 1 and Lower Mold 2] The upper mold 1 and the lower mold 2 are both made of steel.

The upper die 1 is formed of a rectangular flat plate larger than the frame die 3 assembled as shown in FIG. 2 and FIG.
A circular hole 11 into which the center core 4 is fitted is provided, and a rectangular groove 10 into which the upper end of the assembled frame die 3 is fitted is formed.

The lower mold 2 is formed of a rectangular flat plate larger than the frame mold 3 assembled as shown in FIG. 2 and FIG.
A circular hole 21 into which the core 4 is fitted is provided, and a rectangular groove 20 into which the lower end of the assembled frame die 3 is fitted is formed. Incidentally, the groove 20 may be formed by directly cutting the lower die 2 and may be formed by attaching another member with a bolt or the like so as to be attached later. [Regarding Frame Mold 3 and Core 4] As a material for the frame mold 3 and the core 4, the dielectric loss coefficient (dielectric constant × dielectric loss tangent) is equal to or less than the dielectric loss of the elastomer plate 5 [Measuring method: JIS K6
911, test condition: temperature 20 ± 2 ° C., relative humidity 65 ± 5
%, Frequency for measurement: 1 MHz], and epoxy resin, ester resin, and composites of each glass fiber are used. In addition, frame type 3
As described above, the material of the core 4 is set to be equal to or less than the value of the dielectric loss coefficient of the elastomer plate 5, and when it is larger than this, the internal heat generation of the frame 3 and the core 4 is much larger than that of the elastomer plate 5. This is because the inner core 4 and the periphery thereof are locally increased in temperature, which prevents uniform heating of the elastomer plate 5.

As shown in FIG. 2 and FIG. 3, the frame die 3 is formed by combining four separate flat plates 30 into a square shape, and each flat plate 30 has a rubber punch that penetrates in the thickness direction. Equal holes (not shown) are formed. Note that the flat plate 30 is made of glass in consideration of high frequency insulation, compressive strength characteristics, compression creep characteristics, heat resistance, water absorption rate, dimensional stability, dimensional accuracy, adaptability to upsizing, cost, etc. (see Table 1). A number of cloths impregnated with a heat-resistant epoxy resin or ester resin are laminated and heated and pressed to form a plate shape, which is then machined. When the fibrous reinforcing material such as glass fiber is exposed on the machined surface, the exposed fiber surface can be resin-coated by coating the resin material thereon.

Here, in a state in which the above-mentioned four flat plates 30 are fitted into the grooves 10 and 20 of the upper and lower molds 1 and 20 to assemble the molding dies, as shown in FIG. 1 and FIG. The end faces and the bottom faces of the grooves 10 and 20 described above are in contact with each other almost over the entire surface. Therefore, the frame die 3 formed by the four flat plates 30 exerts the same function as the frame die composed of one member, and even when the pressure from the press machine at the time of molding is reduced, It does not adversely affect the height dimension of the.

The core 4 is an epoxy resin (or ester resin) glass fiber composite, and uses a laminated tube manufactured by the filament winding method.

[0018]

[Table 1]

[ About Parallel Electrode Plates P1 and P2] Parallel Electrode Plates
As shown in FIG. 1, P1 and P2 are made of steel plates having a slightly larger area than the upper and lower molds 1 and 2, and are provided with a heating means (not shown) so as to function as a heating plate. As the heating means, for example, it is possible to adopt a configuration in which a heated fluid such as the above or oil is caused to flow in the parallel electrode plates P1 and P2, or a heating wire is embedded in the parallel electrode plates P1 and P2. it can. Here, the heating means is provided in this way in order to prevent heat dissipation from the upper and lower molds 1 and 2 and prevent a temperature difference between the outside and the inside of the laminated body S. [Functions and the like of this dielectric heating device] As shown in FIG. 1, the laminated body S is positioned between the parallel electrode plates P1 and P2, and the high frequency voltage generated by the high frequency oscillator 9 is applied to the parallel electrode plates P1 and P2. When added to each other, the steel plates 6 laminated at substantially equal intervals act as intermediate electrode plates, and all the elastomer plates 5 are heated at the same time regardless of the inner and outer parts, and the parallel electrode plates P1 and P2 are equipped with them. Together with the function of the heating means, the laminate S can be heated to the vulcanization temperature in a short time and almost uniformly. Further, by stopping the oscillator 9, the object to be heated can be controlled at an arbitrary temperature without causing overheating, and this state can be maintained for a long time by supplementing the heat with external heating. That is, according to this method, the rubber bearing can be completed much faster than the conventional method. [About Press Machine] As shown in FIG.
Base 80 and hydraulic cylinder 81 provided above the base 80
And a pressing plate 82 attached to the output shaft end of the hydraulic cylinder 81, and a rod-shaped pressing portion 83 made of a non-conductive member and fixed to the pressing plate 82. In this embodiment, the parallel electrode plate P1 is attached to the lower end of the rod-shaped pressing portion 83, and the parallel electrode plate P2 is attached to the upper surface of the base 80. [Regarding Other Embodiments] In order to maintain the frame shape independently of the frame die, four flat plates may be joined by fastening members. In the above embodiment, the four flat plates 30 are combined in a square shape to form the frame mold 3. However, the non-conductive frame mold 3 having a square inner peripheral surface manufactured integrally is adopted. May be. The frame die 3 can be formed into a wooden shape having an arbitrary shape according to the rubber bearing, and the wooden die can be used to form an epoxy resin or ester resin impregnated cloth in a multi-step manner by laminating it with a hand lay-up method. it can. In addition, the frame mold may be formed by filling a liquid rubber or a thermoplastic material mixed with a fibrous reinforcing material into a mold having an arbitrary shape corresponding to the rubber bearing and curing the mold. The molding die may not have the core 4.

[0020]

The present invention having the above-mentioned structure has the following effects.

As is clear from the section of the embodiments of the invention, dielectric heating molding for rubber bearings is relatively inexpensive, can withstand long-term use, and all elastomer plates are heated substantially uniformly. I was able to provide the mold.

[Brief description of drawings]

FIG. 1 is an explanatory view of a laminated rubber manufacturing apparatus using a dielectric heat-molding die according to an embodiment of the present invention.

FIG. 2 is an explanatory view of the dielectric heating mold and a laminate housed in an internal space of the mold.

FIG. 3 is an external perspective view of the dielectric heating mold.

[Explanation of symbols]

SK dielectric heating mold S laminate 1 Upper mold 2 Lower mold 3 frame type 4 core 10 grooves 20 grooves 30 flat plate

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ Identification code FI B29L 9:00 B29L 9:00 (56) Reference JP-A-11-99520 (JP, A) (58) Fields investigated (Int .Cl. ⁷ , DB name) B29C 33/08 B29C 33/40 B29C 35/12

Claims (13)

(57) [Claims] 1. A dielectric heating integrated using a frequency voltage of 1 to 300 MHz in a mode in which a laminated body formed by alternately laminating a plurality of rectangular elastomer plates and conductive metal plates is applied at least temporarily in the laminating direction. And a non-conductive frame die that is formed by combining a plurality of separate flat plates in a rectangular shape and surrounds the stacking surface of the laminate, and a top and bottom of the frame die. A dielectric heating molding die for rubber bearings, comprising: a conductive upper and lower molds that retain the end frame shape. 2. The dielectric heat-molding die for rubber bearing according to claim 1, wherein a plurality of flat plates are joined by a fastening member so that the frame die independently maintains the frame shape. 3. The flat plate constituting the frame mold is characterized in that a plurality of cloths made of fibrous reinforcing material impregnated with resin are laminated and heated and pressurized to be integrated. A dielectric heating molding die for rubber bearing according to Item 1 or 2. 4. The dielectric heating mold for rubber bearing according to claim 3, wherein the resin constituting the flat plate is an epoxy resin or an ester resin. 5. The dielectric heat-molding die for rubber bearing according to claim 1, wherein the flat plate has a dielectric loss coefficient equal to or less than the value of the dielectric loss coefficient of the elastomer plate. 6. A dielectric heating integrated using a frequency voltage of 1 to 300 MHz in a mode in which a laminated body formed by alternately laminating a plurality of rectangular elastomer plates and conductive metal plates is applied at least temporarily in the laminating direction. A molding die used when forming, a non-conductive frame die having a square inner peripheral surface manufactured integrally, and a conductive die that retains the frame shape of the upper and lower ends of the frame die. A dielectric heat-molding die for rubber bearings, which comprises an upper die and a lower die. 7. The dielectric heating mold for rubber bearing according to claim 6, wherein the frame is formed by laminating resin-impregnated cloth in multiple stages by a hand lay-up method and molding. 8. The dielectric heating mold for rubber bearing according to claim 7, wherein the resin forming the frame mold is an epoxy resin or an ester resin. 9. The dielectric heat-molding die for rubber bearing according to claim 6, wherein the frame die is made by hardening liquid rubber or a thermoplastic material mixed with a fibrous reinforcing material. 10. The upper and lower molds are formed with grooves corresponding to the frame shapes of the upper and lower ends of the frame mold, and the upper and lower ends of the frame mold are fitted in the grooves of the upper and lower molds. The dielectric heat-molding die for rubber bearings according to claim 1 or 6. 11. A mold for a laminated body having through holes in the laminating direction, comprising a non-conductive core that penetrates the through holes of the laminated body. 1. A dielectric heating molding die for rubber bearing according to 1 or 6. 12. The dielectric heating mold for rubber bearing according to claim 11, wherein the resin forming the core is an epoxy resin or an ester resin. 13. The dielectric heating mold for rubber bearing according to claim 11, wherein the core has a dielectric loss coefficient equal to or less than the value of the dielectric loss coefficient of the elastomer plate.