JPH1024419A - Core heating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize more efficient induction heating of a core by a method wherein a conductor, in which electric current flows for induction-heating of the core, is arranged in a shape running along the shape of the outer surface of a molded article. SOLUTION: In the manifold 57 of a molded article 5, a conductor 92 is arranged in a shape along the outer surface 57x of the manifold 57. In addition, the conductor 92 is made of electrically conductive material such as copper and copper-based allow. At use, medium frequency alternate current such as one having the frequency of 7-10kHz is passed from a oscillating device 90 through the conductor 92, resulting in generating alternating field and flowing induction current in a core 6 so as to induction-heat the core 6. Since the conductor 92 is arranged similar to and along the shape of the molded article 5, the arrangement in the form along the shape of the core 6 within the molded article 5 is realized. As a result, this device is favorable of the effective induction heating of the core 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a core heating device. INDUSTRIAL APPLICABILITY The present invention can be used, for example, when a core made of a low melting point metal remaining in a resin molded product such as a resin manifold is eluted by heat.

[0002]

2. Description of the Related Art In recent years, in the field of molded articles, a technique for molding a molded article using a core that can be dissolved by heat has been developed. For example, in the field of intake manifolds for internal combustion engines, a technique for molding a molded article using a core made of a solid low-melting point metal such as bismuth-tin has been developed. According to this technique, since the core can be eluted by heat, it is advantageous for molding a molded article having a complicated shape.

However, elution of the core is not always easy. This is not particularly easy when the molded article has a complicated shape. Therefore, conventionally, as can be understood from FIG. 13, the core 6 made of the low melting point metal remaining in the molded product 5 is used.
As a technique for eluting the oil, a container 10 in which oil 100 is stored
An elution technique using an induction coil 102, an induction coil 102 wound in a cylindrical shape, a heater 103 disposed outside the container 101, and a supply pipe 105 having a jet nozzle 104 facing the core 6 (Japanese Patent Laid-Open No. -247429). According to this elution technology, the oil 1 in the container 101 is surrounded by the cylindrical induction coil 102 while surrounding the molded product 5.
Soak in 00. In this state, the core 6 is heated by induction heating while applying a high-frequency current to the induction coil 102. Further, the oil heated by the heater 103 outside the container 101 is jetted from the jet nozzle 104 toward the core 6, whereby the core 6 is eluted.

[0004]

According to this elution technique, as can be understood from FIG. 13, the molded article 5 with the core 6 remaining is surrounded by the cylindrical induction coil 102.
The core 6 can be induction heated. It is believed that the phenomenon of induction heating is based on eddy current loss or hysteresis loss.

However, according to the above prior art,
The molded product 5 with the core 6 remaining is converted into a cylindrical induction coil 10.
2, the induction coil 102 is not disposed along the outer surface shape of the molded product 5. Therefore, it is not always sufficient for effective induction heating of the core 6. Further, the winding density of the induction coil 102 is also uniform over the axial length direction of the induction coil 102. Therefore, when the molded article 5 or the core 6 has a complicated shape, it is not always sufficient for effective induction heating of the core 6.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and a common problem of each claim is to provide a core heating device that can more effectively induction heat a core. That is, an object of the present invention is to provide a core heating device that more effectively performs induction heating of a core by forming a conductor that performs induction heating along a shape of an outer surface of a molded product.

Another object of the present invention is to provide a core heating device capable of more effectively induction heating a large volume portion of a core having a small volume portion and a large volume portion. A third object of the present invention is to secure the flexibility of the conductor, so that the conductor can be arranged along the shape of the molded product, and thereby the core can be more effectively induction-heated. To provide a sub-heating device.

[0008]

According to a first aspect of the present invention, there is provided a core heating apparatus which covers a molded article having a core having a material eluted by heat as a base material and a core for induction heating the core. A core heating device provided with a flowing conductor, wherein the conductor is arranged in a form conforming to the outer shape of the molded product.

A core heating device according to a second aspect of the present invention is a core heating device which has a core formed of a material eluted by heat and has a small volume portion and a large volume portion. A core heating device provided with a conductor through which a current for inductively heating the conductor flows, wherein the arrangement density of the conductors in the large volume portion is higher than the arrangement density of the conductors in the small volume portion of the core. It is a feature.

A core heating device according to a third aspect of the present invention is a core heating device which covers a molded product having a core made of a material eluted by heat as a base and having a core remaining, and a conductor through which a current for inductively heating the core flows. A child heating device, wherein the conductor is formed by bundling a suitable number of conductive small diameter wires.

According to the first aspect of the present invention, since the conductor is disposed along the outer shape of the molded product, the core remaining in the molded product and the conductor can easily approach each other. This is advantageous for reducing the air gap. Therefore, the magnetic flux generated when an alternating current is applied to the conductor easily passes through the core of the molded product. That is, the ratio of magnetic flux passing through air having higher magnetic permeability than that of the conductor is reduced.

According to the second aspect of the present invention, the arrangement density of the conductor in the large volume portion is higher than the arrangement density of the core in the small volume portion. For this reason, the magnetic flux generated when an alternating current of a predetermined frequency is supplied to the conductor tends to have a higher density in a large volume portion than in a small volume portion of the core. According to the device of the third aspect, the conductor for inductively heating the core is formed by bundling an appropriate number of conductive small diameter wires. Therefore, if the diameter of the conductor is the same as that of a conductor having a single layer structure composed of one wire, the flexibility of the conductor is improved.
Therefore, it is easy to make the conductor follow the outer shape of the molded product.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The apparatus according to the first to third aspects includes a conductor through which a current for inductively heating a core flows. According to the apparatus according to the first and second aspects, the conductor may be a solid shape, a hollow pipe shape, or a wire group in which small diameter wires are bundled. According to the device of the second aspect, the arrangement density of the conductor is set higher in the large volume portion than in the small volume portion of the core. The degree of the high density can be appropriately selected according to the type of the molded product or the core.

According to the third aspect of the present invention, the conductor is formed by bundling an appropriate number of conductive small diameter wires. In bundling, a form in which the small-diameter wire is twisted in a twisted wire form or a form in which the small-diameter wire is substantially parallel to a straight line may be used. The number of pieces to be bundled can be appropriately selected according to the type of the molded product or the core. According to the device according to claims 1 to 3, the frequency of the alternating current flowing through the conductor can be appropriately selected, and may be a high frequency of 30 kHz or more, a medium frequency of 5 to 10 kHz, or a low frequency of 5 kHz or less. It may be a frequency.
When the molded product is a resin, a skin effect that magnetic flux tends to concentrate on the surface layer during induction heating, or a medium frequency that can suppress the skin effect can be adopted in consideration of the heat resistance and the like of the resin. .

As the molded article used in the present invention, a molded article formed using a resin such as a nylon resin as a base material can be adopted.
As the resin, a thermoplastic resin or a thermosetting resin can be adopted. The resin may be reinforced with a reinforcing material such as glass fiber. A molded product generally has a complicated shape enough to be molded using a core. As the molded article, for example, an intake manifold used for an internal combustion engine can be adopted, but it is not limited to this.

The core used in the present invention is based on a material eluted by heat. As such a material, a low melting point metal is typical. As the low melting point metal, for example, a bismuth-based metal, a tin-based metal, a lead-based metal, or the like can be used. Employing a eutectic system is advantageous for lowering the melting point. Specifically, for example, a bismuth-tin alloy can be used as the low melting point metal, and an alloy of 57% bismuth and 43% tin by weight can be used. As the low melting point metal constituting the core, it is preferable that the low melting point metal reaches the melting point and melts before the molded article is melted or thermally damaged.

Further, according to the method using the apparatus of the present invention, a separately heated liquid heat medium can be ejected to the core heated by the core heating device. As the liquid heating medium, polyethylene oxide such as polyethylene glycol can be employed. The molecular weight of polyethylene glycol is desirably 5000 or less. Those having a molecular weight of 5,000 or less have high water solubility and can easily wash the molded article after heating the core. In some cases, a low-melting-point metal in the form of a melt may be used as the above-mentioned liquid heat medium, and in particular, a low-melting-point metal having the same or the same material as the material of the core may be used.

As a mode of use of the device of the present invention, the core remaining in the molded article is induction-heated by the core heating device according to the present invention, and then the core is removed from the core heating device. Thereafter, the core is immersed in a heated liquid heat medium together with the molded article. While immersing in this way, a method of ejecting a high-temperature liquid heat medium to the core to promote elution of the core can be adopted.

As another mode of use of the device of the present invention, a system in which the core is induction-heated by a core heating device in a state where the core is immersed in a high-temperature liquid heat medium can be adopted. . Or, as another mode of use of the device of the present invention, when the core can be eluted only by induction heating,
While performing the operation of induction heating the core with the core heating device according to the present invention, the operation of immersing the core in the high-temperature liquid heat medium or the operation of ejecting the high-temperature liquid heat medium to the core It can be abolished.

[0020]

【Example】

(Embodiment 1) Hereinafter, Embodiment 1 of the present invention will be described with reference to FIGS. This is a device for heating a low-melting-point metal core 6 remaining inside a molded product 5 made of a resin such as nylon. The molded article 5 is a resin intake manifold provided in an internal combustion engine, and includes a plurality of resin branch pipes 56, a resin collecting pipe 57 in which one end of each branch pipe 56 is assembled, and A resin fixing plate 58 fixed to the other end of the branch pipe 56.

A core 6 made of a solid-state low-melting-point metal remains inside the molded article 5. The low-melting point metal constituting the core 6 is a bismuth-tin-based metal, and its melting point is 138.
About 150 ° C. The volume V ₁ inside the collecting pipe 57 of the molded article 5 is larger than the volume V _{2 of one} of the branch pipes 56. Accordingly, the core portion of the core 6 remaining inside the collecting pipe 57 is a large volume portion 6A having a large volume. The core portion remaining inside one of the branch pipes 56 is a small volume portion 6B having a smaller volume than the large volume portion 6A.
It has been. 6s, 6t, and 6u are skirting boards of the core 6.

The core heating device according to this embodiment is schematically shown in FIG. As can be understood from FIG. 1, the core heating device includes an oscillating device 90 for generating an intermediate frequency alternating current,
And a linear conductor 92 connected to the oscillation device 90. The conductor 92 is provided in a form that follows the outer shape of the molded product 5. FIG. 2 shows a cross section of the branch pipe 56. As shown in FIG. 2, the cross section of the branch pipe 56 has a cylindrical shape, and the conductor 92 is disposed along the outer surface of the branch pipe 56.

In other words, in the branch pipe 56, the conductor 92 is also bent so as to follow the curvature of the outer surface 56x of the branch pipe 56. Therefore, the small volume portion 6B of the core 6 in the branch pipe 56 is formed.
The conductor 92 is disposed along the outer surface of the conductor 92. Therefore, according to the present embodiment, as can be understood from FIG. 2, the conductor 92 in the branch pipe 92 has a form in which “substantially Δ” is continuous.

Further, as can be understood from FIG.
In the collecting pipe 57, the conductor 92 is disposed along the outer surface 57x of the collecting pipe 57. Note that the conductor 92 can be formed of a conductive material, for example, copper or a copper-based alloy. In use, a medium-frequency alternating current (for example, 7 kHz to 10 kHz) is supplied to the conductor 92 from the oscillation device 90. As a result, an alternating magnetic field is generated, an induced current flows through the core 6, and the core 6 is induction-heated.

According to this embodiment, the conductor 92 is formed of the molded article 5
Are arranged in a manner similar to the shape of the core 6, so that they are arranged in a form along the shape of the core 6 inside the molded product 5. Therefore, it is advantageous for effectively heating the core 6 by induction. By the way, there is a skin effect during induction heating. As described above, the skin effect is a phenomenon in which the surface layer of an object to be heated by induction is intensively heated. The higher the frequency, the more concentrated the surface layer of the object is heated by the skin effect. In this case, there is a possibility that the resin portion of the molded product 5 facing the surface portion of the core 6 to be overheated is thermally degraded.

In this respect, in this embodiment, the frequency of the alternating current applied to the conductor 92 is a medium frequency (for example, 7 kHz to 10 kHz).
z), an excessive skin effect can be suppressed.
Therefore, it is advantageous to suppress the thermal deterioration of the resin molded product 5 facing the surface layer of the core 6 to be induced and heated. FIG.
Shows a timing chart when induction heating is performed.
The horizontal axis in FIG. 3 indicates elapsed time, and the vertical axis indicates temperature. The filled Xc portion on the horizontal axis indicates the time of energization. A characteristic line A indicates the surface temperature of the conductor 92, and a characteristic line B indicates the temperature of the surge tank of the molded product 5, that is, the temperature of the large volume portion 6A of the core 6. In this embodiment, interval heating is performed in which the energization time is turned on and off alternately. The reason is that the Joule heat generated by the induction heating in the core 6 is promoted to be transmitted to the inside of the core 6, thereby suppressing the overheating of the surface of the core 6 and suppressing the thermal deterioration of the molded product 5. To do that.
In this embodiment, the first ON time is long, and the ON time is shortened as time elapses.

(Embodiment 2) FIG. 4 shows a main part of Embodiment 2. The second embodiment has basically the same configuration as the first embodiment. Therefore, the same portions are denoted by the same reference numerals. In this example, the same operation and effect as in the first embodiment can be obtained. However, according to this core heating device, the conductor 9 surrounding the branch pipe 56
2 is a first divided body 92 movable in the directions of arrows E1 and E2.
k and the second divided body 92 movable in the directions of the arrows F1 and F2.
h. Arrows E1, E2, arrow F
The directions F1 and F2 are directions along the radial direction of the branch pipe 56.

When setting, the first divided body 92
k is moved in the direction of arrow E1, and the second divided body 92h is moved in the direction of arrow F1. When the set is released, the first divided body 92k is moved in the direction of arrow E2, and the second divided body 92h is moved in the direction of arrow F2. In this case, the setting or the canceling of the setting is facilitated. (Embodiment 3) FIG. The third embodiment has basically the same configuration as the first embodiment. Therefore, the same parts are denoted by the same reference numerals. In this core heating device, as shown in FIG. 2, the conductor 92 is also provided along the outer surface 57 x of the collecting pipe 57 of the molded product 5 and the outer surface 56 x of the branch pipe 56.

Since the large volume portion 6A of the core 6 has a large volume, the degree of temperature rise and the dissolution tend to be delayed. According to this point, according to the third embodiment, the conductor 9 in the large volume portion 6A of the core 6 is used.
The arrangement density of 2 is higher than the arrangement density of the core 6 in the small volume portion 6B. Therefore, induction heating in the large volume portion 6A of the core 6 can be effectively performed, which is advantageous for heating the large volume portion 6A of the core 6 early. Therefore, even if the large volume portion 6A of the core 6 tends to delay the elution, it is advantageous to effectively elute the large volume portion 6A.

Further, according to the third embodiment, similarly to the first embodiment, since the conductor 92 is disposed in a form conforming to the shape of the molded product 5, it follows the shape of the core 6 inside the molded product 5. In this sense, the core 6 is also advantageous for effective induction heating. Fourth Embodiment FIG. 6 shows a conductor 92 used in a fourth embodiment.
The fourth embodiment has basically the same configuration as the third embodiment shown in FIG. However, in the fourth embodiment, the conductor 92 is configured by a line group in which an appropriate number of small wires having conductivity are bundled.
That is, FIG. 6 shows a cross section of the conductor 92. FIG.
The side view of the principal part of FIG.

As shown in FIG. 6, the conductor 92 includes a conductive central core 95 located at the center, a conductive outer layer 96 disposed outside the central core 95, and an outer layer 96.
And an insulating covering portion 97 for covering the same. The diameter of the conductive portion of the conductor 92 is indicated by Dc. The insulating coating portion 97 is formed of an electrically insulating material such as rubber or resin. The central core portion 95 is formed by twisting and binding an appropriate number of small diameter wires 95c. The outer layer portion 96 is located outside the central core portion 95, and is formed by twisting and binding an appropriate number of small diameter wires 96c. As shown in FIG. 7, the twist angle of the small-diameter wire 95 c in the center core 95 is the same as the small-diameter wire 96 in the outer layer portion 96.
The twist angle is larger than c.

As described above, the conductor 92 is formed by the small-diameter wires 95c, 96
Since the conductors have the same diameter Dc as compared to the case where the conductor has a single-layer structure, the flexibility of the conductor 92 is ensured as compared with the case where the conductor has a single-layer structure. This is advantageous for causing the conductor 92 to follow the outer surface of the molded article 5 in a similar manner. Moreover, when a tensile force acts on the stranded conductor 92 in the longitudinal direction thereof, the extensibility of the conductor 92 is easily secured as compared with a non-stranded conductor having a single layer. Also in this sense, it is advantageous to make the conductor 92 conform to the outer surface shape of the molded product 5 in a similar manner.

Therefore, even when the molded article 5 has a complicated shape, it is advantageous to dispose the conductor 92 in a form following the outer shape of the molded article 5. Therefore, it is advantageous to dispose the conductor 92 in a form following the shape of the core 6 inside the molded product 5. Therefore, it is suitable for effectively heating the core 6 by induction. According to the fourth embodiment, similarly to the second embodiment, the arrangement density of the conductors 92 in the large volume portion 6A of the core 6 is higher than the arrangement density of the conductor 6 in the small volume portion 6B of the core 6. Therefore, the induction heating in the large volume portion 6A of the core 6 can be effectively performed, and the large volume portion 6 of the core 6 where the elution tends to be delayed.
This is advantageous for heating A early.

FIG. 8 shows another example of the conductor 92. Conductor 9
Numeral 2 is formed by twisting a plurality of small diameter wires 92f and has a stranded wire structure. (Application Example) An application column will be described. According to this application example, the core 6 of the molded article 5 is heated using the core heating device described above,
Thereafter, the molded product 5 is removed from the core heating device together with the core 6, and the molded product 5 is immersed in the heated liquid heat medium 2 as described later.

Hereinafter, this application example will be described. A heating bath 15 is provided inside the bathtub 1 as a container. Heating oil 15k (Parel Thermo # 400) is stored in the heating chamber 15x of the heating tank 15. The accommodation room 10 is formed on the inner surface of the heating tank 15. The accommodation room 10 is sealed with a cover plate 1f. The liquid heating medium 2 is stored in the storage chamber 10. As the liquid heat medium 2, liquid polyethylene glycol (molecular weight: 4000) is employed.

The bath 1 is provided with a heating device 3 for heating the heating bath 15. Heating chamber 15 of heating tank 15
A communication pipe 30 is provided between x and the heating device 3. The heating device 3 includes a heating source and a supply source. Therefore, when the heating device 3 is operated, the heating oil 15k in the heating chamber 15x is circulated to the heating device 3 through the communication pipe 30, and
Heated to about 0 to 350 ° C., the heated oil 15 k is returned to the heating chamber 15 x of the heating tank 15 via the communication pipe 30. In this way, the liquid heat medium 2 in the storage chamber 10 is heated and kept warm.

The molded product 5 is held by the mounting jig 14 of the bathtub 1, whereby the molded product 5 is stored in the storage room 10 of the bathtub 1. As a result, the molded article 5 is immersed in the liquid heat medium 2 in the storage chamber 10. The supply pipe 7 is provided in the accommodation room 10 of the bathtub 1. The supply pipe 7 is immersed in the liquid heat medium 2 in the storage chamber 10. The supply pipe 7 includes an ejection nozzle 70 functioning as an ejection outlet, and a passage 72 communicating with the ejection nozzle 70. The ejection nozzle 70 is disposed in the accommodation room 10 and faces the core 6 of the molded product 5 so as to approach.

As shown in FIG. 9, a pump device 8 as a liquid heating medium supply means is provided in the bathtub 1 via a holding table 80. The pump device 8 includes a gear pump 82 that performs a pumping operation, a drive motor 83 that rotates the gear pump 82, and a suction port 84 that connects the inside of the gear pump 82 and the inside of the storage chamber 10. When the pump device 8 is operated, the liquid heating medium 2 heated to a certain degree and accommodated in the accommodation chamber 10 is sucked through the suction port 84, is fed to the passage 72 of the supply pipe 7, and is ejected from the ejection nozzle 70. 2A
Is ejected toward the core 6 of the molded article 5. In this way, suction and ejection continue, and the liquid heat medium 2 in the storage chamber 10 circulates.

As shown in FIG. 10, a tubular wall 7i constituting the supply pipe 7 is provided with a heating means 75 immediately before forming a sleeve.
Are buried almost coaxially. In this embodiment, the immediately preceding heating means 75 is constituted by a sheathed heater provided with a heating wire. The immediately preceding heating means 75 is provided in the passage 72 of the supply pipe 7 on the side near the ejection nozzle 70 and in the accommodation chamber 10 of the bathtub 1.
Is provided. The immediately preceding heating means 75 is for heating the liquid heating medium 2 in the passage 72 immediately before the ejection from the ejection nozzle 70 to increase the temperature.

At the time of use, as described above, the molded product 5 having the core 6 heated by the above-described core heating device is used, and the molded product 5 is attached to the mounting jig 14. In this state, the molded article 5 is immersed in the liquid heating medium 2 in the storage chamber 10. Therefore, since the heat of the liquid heat medium 2 in the storage chamber 10 is transmitted to the core 6 of the molded article 5, the core 6
Is promoted.

When the core 6 is eluted, the liquid heating medium 2 in the storage chamber 10 is driven by the pump device 8 to drive the suction port 8.
4, and is ejected from the supply nozzle 7 through the passage 72 of the supply pipe 7.
0, and is ejected from the ejection nozzle 70 toward the core 6 of the molded article 5 as the liquid heat medium 2A. The ejected liquid heat medium 2 </ b> A hits the core 6 of the molded product 5. Thereby, the core 6 is melted or eluted.

According to the present embodiment, the temperature of the liquid heat medium 2A ejected from the ejection nozzle 70 is raised to about 200 to 240 ° C. by the immediately preceding heating means 75 immediately before ejection. Specifically, when the liquid heat medium 2A whose temperature has been raised by the immediately preceding heating means 75 immediately before being ejected from the ejection nozzle 70 is ejected from the ejection nozzle 70, the liquid heat medium 2A first protrudes from the molded product 5 in the core 6. The core part inside the molded article 5 is melted or eluted in order after the baseboard part is hit and the baseboard part is eluted.

The mounting jig 14 is set so as to gradually descend as the core 6 elutes. Therefore, an increase in the interval between the core 6 and the ejection nozzle 70 is suppressed, and the elution of the core 6 is performed effectively. The core component eluted by the liquid heating medium 2 </ b> A ejected from the ejection nozzle 70 sinks to the bottom of the storage chamber 10 due to a difference in specific gravity and deposits as a deposit B.

In consideration of enhancing the dissolving property of the core 6, it is preferable that the liquid heat medium 2A ejected from the ejection nozzle 70 hits the core 6 in a turbulent flow. FIG.
The case where the liquid heat medium 2A ejected from the ejection nozzle 70 hits the core 6 in a turbulent manner is schematically shown. FIG. 12 schematically shows a case where the liquid heat medium 2A ejected from the ejection nozzle 70 hits the core 6 in a laminar flow. In the case of turbulence, the frequency of contact between the liquid heating medium 2A and the core 6 increases, and the dissolution of the core 6 improves. Therefore, it is preferable to determine the flow rate and the like so that the ejected liquid heat medium 2A becomes turbulent. According to a test conducted by the present inventors, a laminar flow was obtained when the ejection amount was 20 [m ³ / min], and a turbulent flow was obtained when the ejection amount was [40 m ³ / min].

As described above, according to the present embodiment, the liquid heat medium 2A ejected from the ejection nozzle 70 is heated by the immediately preceding heating means 75 immediately before ejection, and the temperature is raised to around 200 to 240 ° C. As described above, the temperature of the liquid heat medium 2 jetted to the core 6 is further increased immediately before the jetting and becomes hot. Therefore,
This is advantageous for applying the hot liquid heat medium 2 </ b> A to the core 6.
Therefore, the core 6 can be effectively melted or eluted.

In this embodiment, as described above, polyethylene glycol is employed as the liquid heat medium 2, 2A. Although polyethylene glycol depends on the molecular weight, generally, the oxidation limit temperature is around 175 to 230 ° C. The oxidation limit temperature means a temperature at which polyethylene glycol is degraded and its hue changes if the temperature is maintained for a predetermined time. When the liquid heat medium 2, 2A is held near the oxidation limit temperature for a long time, thermal deterioration of the liquid heat medium 2, 2A is promoted, and the life is shortened.

In this respect, the liquid heating medium 2 is preheated to a certain temperature by the heating device 3 as in the present embodiment, and the liquid heating medium 2A is heated immediately before the ejection so that the liquid heating medium 2A is suitable for elution.
If the temperature is raised by 5, the temperature of the liquid heating medium 2 in the storage chamber 10 can be kept as low as possible in a mode other than immediately before ejection. Therefore, according to the present embodiment, the thermal deterioration of the liquid heat medium 2, 2A can be suppressed as much as possible, which is advantageous for extending the life.

According to this embodiment, since the immediately preceding heating means 75 is located in the liquid heating medium 2 accommodated in the accommodation chamber 10, the heat generated by the immediately preceding heating means 75 is In addition to being transmitted to the heat medium 2, the accommodation room 10
It is also transmitted to the liquid heating medium 2 housed therein. Therefore, it is also advantageous to preheat the core 6 of the molded article 5 immersed in the liquid heat medium 2 in the storage chamber 10 while suppressing the capacity of the heating device 3 from becoming excessive.

(Supplementary Note) The following technical idea can be understood from the above-described embodiment. In each of the claims, the core heating device is characterized in that the conductor is arranged substantially along the curvature of the outer surface of the branch pipe. In each claim, the core heating device is characterized in that the conductor is movable in the radial direction of the branch pipe. ○ Using a molded product in which a core whose material can be dissolved by heat as a base material remains, and a conductor through which a current for inductively heating the core flows,
A core heating method in which a conductor is provided in a form conforming to the outer surface shape of a molded product, and a current is applied to the conductor in that state to induce induction heating of the core.

[0050]

According to the apparatus according to the first aspect of the present invention, the induction heating of the core can be performed more effectively by forming the conductor to be subjected to the induction heating along the outer shape of the molded article. This is advantageous for elution of the core. According to the device according to the second aspect, of the core having the small volume portion and the large volume portion, the large volume portion can be more effectively induction-heated. This is advantageous for elution of the core.

According to the device according to the third aspect, it is advantageous to ensure the flexibility of the conductor. Therefore, even if the molded product or the core has a complicated shape, it can be formed along the shape of the molded product. This is advantageous for arranging the conductor. This allows the core to be more effectively induction-heated. This is advantageous for elution of the core.

[Brief description of the drawings]

FIG. 1 is a configuration diagram illustrating a use state according to a first embodiment.

FIG. 2 is a cross-sectional view showing a state in which a conductor is provided along the outer surface of a branch pipe.

FIG. 3 is a timing chart when induction heating is performed.

FIG. 4 is a cross-sectional view according to a second embodiment showing a state in which a conductor is provided along the outer surface of the branch pipe.

FIG. 5 is a configuration diagram illustrating a use state according to a third embodiment.

FIG. 6 is a transverse sectional view of a conductor according to a fourth embodiment.

FIG. 7 is a side view of a main part of a conductor according to a fourth embodiment in a state where an insulating coating is removed.

FIG. 8 is a side view of a main part of another conductor in a state where an insulating coating is removed.

FIG. 9 is a configuration diagram of an apparatus according to an application example.

FIG. 10 is a configuration diagram showing a cross section of a passage of a device according to an application example.

FIG. 11 is a configuration diagram showing a form in which a jet hits a core in a slightly turbulent manner.

FIG. 12 is a configuration diagram showing a mode in which a jet hits a core in a laminar flow.

FIG. 13 is a configuration diagram of an apparatus according to a conventional example.

[Description of Signs] In the drawing, 1 is a bathtub, 10 is a storage room, 2, 2A, 2B, 2C
Is a liquid heating medium, 5 is a molded product, 56 is a branch pipe, 57 is a collecting pipe, 6 is a core, 8 is a pump device, 70 is a jet nozzle, 7
2 is a passage, 75 is the immediately preceding heating means, 90 is an oscillating device, 92
Indicates a conductor.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Ryuzo Oide 3-11-12 Ohori, Matsubara-shi, Osaka Prefecture Inside Osaka Giken Co., Ltd.

Claims (3)

[Claims] 1. A core heating device comprising: a core having a core made of a material eluted by heat as a base material and covering a molded article, and a conductor through which a current for inductively heating the core flows. The core heating device, wherein the conductor is provided in a form following the outer shape of the molded product. 2. A conductor having a base material made of a material eluted by heat and having a small volume part and a large volume part covering a molded article on which a residual core remains and through which a current for inductively heating the core flows. Wherein the arrangement density of the conductors in the large volume portion is higher than the arrangement density of the conductors in the small volume portion of the core. apparatus. 3. A core heating apparatus comprising: a core having a core made of a material eluted by heat as a base material and covering a molded article, and a conductor through which a current for inductively heating the core flows. A core heating device, wherein the conductor is formed by bundling an appropriate number of small diameter wires having conductivity.