JP2005288964A - Elution device and elution method for molten core for molding hollow resin molded article - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a simply constituted elution device for a molten core, which makes the capacity of an elution tank small and which enables an efficient heating method for a liquid thermal medium, and an elution method. <P>SOLUTION: This elution device is equipped with: the bottomed tube-shaped elution tank 12 which is placed on an installation base 10, and which is composed of a non-metallic inorganic material, that is, glass, ceramics, etc., having excellent insulation properties, heat resistance, chemical agent resistance and oil resistance; a heating body 3 which is wound around the outer periphery of the elution tank 12 in a coiled manner, and which is composed of a hollow pipe made of copper; a high-frequency power source 5 which is connected to both ends of the heating body 3 via a connection terminal part 4; and an insulative hose 14 which is coupled to both ends of the heating body 3. The hollow resin molded article 9 is supported by an implement, and installed in the elution tank 12. After lutron as a liquid thermal medium 1 is injected up to a predetermined position in the elution tank 12, heat is generated by applying a high-frequency voltage to the heating body 3, so that only the molten core 9a in the elution tank 12 can be selectively eluted. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a melting core elution apparatus and an elution method for molding a hollow resin molded product.

  As a method of manufacturing a resin molded product having a hollow part of a complicated shape, a hollow core made of a low melting point metal is made, and the resin is over-molded around this and then molded into a hollow resin. The molten core is immersed in a liquid heat medium, and the liquid heat medium is heated by a heating means and held at a temperature not lower than the melting point of the molten core and not higher than the thermal deformation temperature of the hollow resin molded product. The elution lost core method is known.

  However, this lost core method has a problem that it is necessary to raise the temperature of the liquid heat medium and keep it warm, it must be heated for a long time, and it takes a long melting time.

  Therefore, in addition to the conventional heating means for the liquid heat medium, a pump and nozzle for sucking and discharging the liquid heat medium are installed, and a jet is discharged through the nozzle to the hollow portion of the hollow resin molded product. Thus, a method has been proposed in which the molten core is forced to flow and is completely eluted at high speed (see Patent Document 1).

  In addition, a high-frequency voltage is applied to a heating body consisting of a hollow tube wound around a hollow resin molded product in a liquid heat medium in an elution tank, and heat generated by eddy current loss of the heating body is utilized. A method for eluting the molten core has also been proposed. As shown in FIG. 3, the apparatus includes an elution tank 2 in which the liquid heat medium 1 is placed, a heating body 3 composed of a copper hollow tube immersed in the elution tank 2 and wound in a coil shape, A cooling device comprising a high-frequency power source 5 connected to both ends of the body 3 via connection terminal portions 4, a water cooling jacket 7 and a circulation pump P1 connected to both ends of the heating body 3 via insulating tubes 6, A heating device including a heater 8 connected to the elution tank 2 and a circulation pump P2; a hollow resin molded product 9 is disposed on the inner side surrounded by the heating body 3; Only the molten core 9a in the hollow resin molded product 9 is selectively eluted by heating with the heater 8 while circulating at P2 and applying a high frequency voltage to the heating element 3 to generate heat.

  Since the melting core 9a in the hollow resin molded product 9 that is the object to be melted is selectively heated, it can be efficiently eluted.

As the liquid heat medium 1, Lutron (trade name: manufactured by BASF Corporation) made of deformed polyethylene glycol is used. Further, in order to prevent abnormal heating of the heating body 3 main body, the same lutron is used as a coolant, and cooling is performed by circulating the inside of the heating body 3 via the circulation pump P1 while cooling with the jacket 7.
JP 2001-62845 A (P2001-62845A)

  However, in the conventional elution apparatus, since the hollow resin molded product and the heating body are accommodated in the elution tank, the size of the heating body is set to the maximum size of the hollow resin molded product that is assumed to be the size of the elution tank. I had to add it. Therefore, when the elution tank is large, a large amount of a liquid heat medium is required, and a large amount of heating energy for heating the liquid heat medium is required, which causes a problem in terms of cost.

  In addition, the same medium as the liquid heat medium is used as a coolant for preventing abnormal heat generation of the heating element, but the unit price of the liquid heat medium itself is expensive and there is a problem in terms of cost because it is used in large quantities. It was.

  And since the temperature is raised to near the boiling point of the liquid heat medium in the elution tank, the degreasing treatment efficiency decreases due to evaporation, thermal degradation, increase in viscosity due to contamination of foreign substances such as elution. Accordingly, there is a problem that the liquid heat medium needs to be replaced periodically and the usage amount is large, so that a running cost is required.

  Also, in a factory, it is necessary to put a plurality of hollow resin molded products in the elution tank in order to improve productivity. Then, in the method in which the liquid heat medium is discharged to the hollow portion of the hollow resin molded product through the nozzle by using the pump, the final method is to install a plurality of discharge nozzles and pipes in addition to the pump. Had the problem of requiring large-scale incidental facilities.

  And there was a problem that maintenance of ancillary facilities was required and it took time and effort.

  Further, in the method of winding the periphery of the hollow resin molded product in a coil shape with a heating body, in order to increase the heating efficiency, the number of windings and winding of the heating body are adjusted according to the size and shape of the hollow resin molded product. There is a problem that it is necessary to set the diameter of rotation and the equipment must be updated every time a new product is launched.

  The present invention solves the above problems, and its object is to provide a melting core elution apparatus with a simple apparatus configuration, a small elution tank capacity, and an efficient heating method for the melting core. And an elution method.

  In order to solve the above object, a melting core elution apparatus according to the present invention includes a hollow resin molded product containing a melting core made of a low melting point metal, an elution tank for containing a liquid heat medium, and an elution tank of the elution tank. And heating means for eluting the molten core through heating of the liquid heat medium (first invention).

  In a second aspect based on the first aspect, the heating means includes a coil-shaped heating body wound around the elution tank, and the heating body has a hollow portion capable of supplying water therein. It is characterized by that.

  According to a third invention, in the first or second invention, the elution tank is made of glass, ceramic, or the like, which is a nonmetallic inorganic material.

  In the melting core elution method of the fourth invention, the melting core of a hollow resin molded product containing a melting core made of a low melting point metal is eluted by the elution apparatus of any one of the first to third inventions. It is characterized by.

  The hollow resin molded product of the fifth invention is characterized by being molded by the elution method of the fourth invention.

  In the melting core elution apparatus according to the present invention, the size of the elution tank is compared with that of a conventional elution tank because the heating element is disposed outside the elution tank, such as by winding the outer periphery of the elution tank in a coil shape. Thus, it is possible to reduce the heating element by the arrangement space. Therefore, the volume of the elution tank is reduced, the liquid heat medium to be used is small, and the heating energy required for heating the liquid heat medium is also small.

  Furthermore, since water can be used as a coolant for preventing abnormal heat generation, the amount of liquid heat medium used as the entire elution apparatus is small, and the running cost is low.

  Therefore, in the present invention, a plurality of types of elution tanks having different diameters, heights and depths are prepared, and coils are provided with the number of windings optimized for these, so that hollow resin molded products having various sizes can be obtained. It can be used and efficient elution work is possible.

  Furthermore, since the volume of the elution tank is small, the heat unevenness of the liquid heat medium is eliminated, and the eluted molten core can be maintained in a molten state without being re-solidified at the bottom of the elution tank.

  In the method of the present invention, a hollow resin molded product containing a molten core made of a low melting point metal is disposed inside the elution tank, and a heating body made of a hollow tube is wound around the elution tank in a coil shape. And a melting core elution device and an elution method for eluting the molten core.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the present embodiment, the same portions as those in the related art will be described using the same reference numerals and only different portions will be described using different reference numerals.

  FIG. 1 is an overall schematic view showing a melting core elution apparatus in the present embodiment. As shown in FIG. 1, the elution apparatus is a bottomed cylindrical shape made of glass, ceramic, etc., which is a non-metallic inorganic material placed on a setting table 10 and has high insulation, heat resistance, chemical resistance, and oil resistance. An elution tank 12, a heating body 3 made of a copper hollow tube that winds the outer periphery of the elution tank 12 in a coil shape, a high-frequency power source 5 connected to both ends of the heating body 3 via connection terminal portions 4, An insulating hose 14 connected to both ends of the heating element 3 is provided. In the present embodiment, the heating body 3, the connection terminal portion 4, and the high-frequency power source 5 constitute the heating means referred to in claim 1.

  The other end side of the insulating hose 14 connected to the lower drawing end of the heating element 3 is connected to a tap faucet 18 and the other end side of the insulating hose 14 connected to the upper drawing end of the heating element 3 is It is drawn into the discharge port 16. Then, in order to prevent abnormal heating of the main body of the heating body 3, tap water is passed through the heating body 3 and used as cooling water, and then discharged from the discharge port 16.

  The hollow resin molded product 9 is supported by a jig (not shown) and installed in the elution tank 12. And after inject | pouring the room temperature lutron used as the liquid heat medium 1 to the predetermined position in the elution tank 12, it applies only the high frequency voltage to the heating body 3, and it is made to heat | fever, only the melting core 9a in the elution tank 12 is made. Elute selectively.

  Melting occurs from a portion close to the heating element 3 and is sequentially melted to the center. The melted core flows down from the lower side opening of the hollow resin molded product 9 and stays at the bottom of the elution tank 2 in a molten state.

  FIG. 2 is a diagram illustrating a state after elution of the molten core in the present embodiment. As shown in FIG. 2, after all the molten cores 9a are eluted and the high frequency power source 5 is cut off, the liquid heat medium 1 is cooled to an appropriate temperature by continuing to flow tap water.

  The hollow resin molded product 9 is shipped as a product after an appropriate degreasing treatment. The molten core 9a can also be reused as a molten core of a hollow resin molded product after the degreasing treatment.

1 is an overall schematic view showing a melting core elution apparatus in the present embodiment. It is a figure which shows the state after the elution of the molten core in this embodiment. It is the schematic of the apparatus for enforcing the conventional high frequency induction heating method.

Explanation of symbols

1 Liquid heat medium 2 Elution tank 3 Heating body (heating means)
4 Connection terminal (heating means)
5 High frequency power supply (heating means)
6 Insulating tube 7 Water-cooled jacket 8 Heater 9 Hollow resin molded product 9a Melting core 10 Installation base 12 Elution tank 14 Insulating hose 16 Outlet 18 Faucet P1, P2 Circulation pump

Claims (5)

A hollow resin molded product containing a molten core made of a low melting point metal, and an elution tank for containing a liquid heat medium;
A melting core elution apparatus comprising heating means disposed outside the elution tank and for eluting the molten core through heating of the liquid heat medium.   The said heating means is provided with the coil-shaped heating body wound around the outer side of the said elution tank, This heating body has the hollow part which can be supplied with water in the inside. The melting core elution apparatus as described.   3. The melting core elution apparatus according to claim 1, wherein the elution tank is made of a non-metallic inorganic material such as glass or ceramic.   A melting core elution method, wherein the melting core of a hollow resin molded product containing a melting core made of a low melting point metal is eluted by the elution apparatus according to any one of claims 1 to 3. A hollow resin molded product, which is molded by the elution method according to claim 4.

Images