JP6512505B2 - Casting mold - Google Patents

Description

  The present invention relates to a casting mold.

  A resin molded product such as a bathtub installed in a bathroom is usually manufactured by cast molding using a cast molding die 1 as shown in FIG.

  The cast molding die 1 is provided with a cavity 4 in the shape of a molded product between the upper mold 2 and the lower mold 3, and with the upper mold 2 and the lower mold 3 heated, the injection port After filling the resin material of the raw material from the gate 5 to the cavity 4, it is cooled and the molded product is molded.

  In order to facilitate the filling of the resin material in such a casting mold 1 and to prevent the gas from remaining in the cavity 4 after filling, the gas is usually discharged from the cavity 4. The exhaust passage 6 is detachably provided.

  However, if resin material is excessively injected into the cavity 4 for this exhaust passage 6, excess resin material may flow into the exhaust passage 6, and in that case, maintenance is performed by removing the exhaust passage 6 each time. There is a problem that the molding operation becomes complicated because it is necessary.

  Then, in order to solve such a problem, the casting mold 1 which provided the resin fastener which consists of felts in the part which the cavity 4 and the exhaust passage 6 contact is proposed (for example, patent document 1) See).

  FIG. 7 shows a schematic cross-sectional view of a casting mold 1 using the resin fastener 75 made of such a felt. In the casting mold 1, the resin fastener 75 made of felt is discharged through the gas in the cavity 4, but in order to suppress the inflow of the excessively injected resin material, the inflow of the resin material into the exhaust passage 6 Can be prevented.

  Further, as another resin fastener, a cylindrical resin fastener 76 having a vent 77 in the direction connecting the cavity 4 and the exhaust passage 6 has also been proposed (see, for example, Patent Document 2).

  FIG. 8 shows a schematic cross-sectional view of a cast molding die 1 using a cylindrical resin fastener 76 having a vent 77 in the direction connecting the cavity 4 and the exhaust passage 6.

  In the casting mold 1, the exhaust tube 78 is inserted into the exhaust passage 6 so as to communicate with the vent hole 77 of the resin fastener 76, and the gas in the cavity 4 is the vent hole of the resin fastener 76. The air is exhausted to the outside of the casting mold 1 through 77 and the exhaust tube 78. Thus, the resin material can be prevented from flowing into the exhaust passage 6.

JP 2007-55103 A Japanese Patent Application Laid-Open No. 2007-30324

  However, when a molded article is molded using the resin fasteners described in Patent Documents 1 and 2, the molded article is demolded from the cast molding mold 1 after molding, and then molded into the cast molding mold 1. Since the resin fastener remains, the exhaust passage 6 has to be removed from the mold to remove the resin fastener. Therefore, there is a problem that post-processing after molding is required.

  The present invention has been made in view of the above-described conventional problems, and in the production of a molded article by a cast molding die using a resin fastener, exhausting from the cast molding die after molding of the molded article It is an object of the present invention to provide a casting mold which does not need to remove the passage and remove the resin fastener.

  The present invention is characterized by the following in order to solve the above-mentioned problems.

A casting molding metal comprising a cavity for resin molding between an upper mold and a lower mold, and at least one of the upper mold and the lower mold being provided with an exhaust passage for discharging a gas in the cavity. A mold is provided with a vent in a direction connecting the cavity and the exhaust path at a portion where the exhaust path and the cavity are in contact, and the gas in the cavity is exhausted through the vent hole to the exhaust path. A resin fastener for preventing the inflow of the resin material is provided, and a narrow diameter portion having a diameter smaller than the outer diameter of the resin fastener is formed at an end of the resin fastener on the cavity side. An extremely narrow diameter portion having a diameter smaller than that of the narrow diameter portion is formed on the exhaust passage side, and a neck portion into which the resin material formed by the difference in diameter of the narrow diameter portion and the extremely narrow diameter portion is inserted. The resin that has entered the neck after molding Curing of fees, the resin fastening part is characterized to be a part of the molded article.

  According to the present invention, there is no need to remove the resin fastener by removing the exhaust passage from the cast molding die after molding of the molded product in the manufacture of a molded article by the cast molding die using the resin fastener. It becomes possible to provide a casting mold.

It is a schematic sectional drawing of the mold for cast molding using the resin fastener of this invention. (A) is a schematic cross-sectional view of a resin fastener, (b) is a schematic perspective view of the resin fastener. It is a back surface perspective view of the bathtub of a molded article. It is a fragmentary sectional view in the state where an apron was made to hold a bathtub. It is a perspective view of a state where an apron is made to hold a tub. FIG. 6 is a schematic cross-sectional view of a conventional casting mold having an exhaust passage. It is a schematic sectional drawing of the cast molding die using the resin fastener which consists of felt. It is a schematic sectional drawing of the casting mold which used the resin fastener which has a vent.

  Hereinafter, the cast molding die of the present invention will be described in more detail by way of embodiments for carrying out the invention.

  The mold for cast molding according to the present embodiment includes a cavity for resin molding between the upper mold and the lower mold, and exhausts the gas in the cavity to at least one of the upper mold and the lower mold. It is a casting mold having a channel. And, in the part where the exhaust passage and the cavity are in contact, there is a vent in the direction connecting the cavity and the exhaust passage, and the gas in the cavity is discharged through this vent to prevent resin material from flowing into the exhaust passage. Equipped with

In addition, a narrow diameter portion whose diameter is smaller than the outer diameter of the resin fastener is formed at the end of the resin fastener on the cavity side, and the diameter is further smaller than the narrow diameter portion on the exhaust passage side of the narrow diameter portion. An extremely narrow diameter portion is formed, and a constricted portion into which a resin material formed by the difference in diameter between the narrow diameter portion and the extremely narrow diameter portion is inserted is provided. Then, the resin retaining portion 7 becomes a part of the molded product due to the curing of the resin material that has entered the constricted portion after molding.

  FIG. 1 shows a schematic cross-sectional view of an embodiment of a casting mold 1 of the present invention. The cast molding die 1 of the present embodiment is a cast molding die 1 used for molding a bath, and the upper mold 2, the lower mold 3, the cavity 4, the gate 5, the exhaust passage 6, the resin retaining A tool 7 and an exhaust tube 78 are provided.

  A cavity 4 for resin molding is formed between the upper mold 2 and the lower mold 3, and an exhaust path 6 is detachably provided in the upper mold 2. A resin fastener 7 having a vent 71 is attached to a portion where the cavity 4 of the upper mold 2 and the exhaust passage 6 are in contact with each other.

  In addition, the exhaust tube 78 has one end projecting into contact with the resin fastener 7 and communicating with the vent hole 71 formed in the resin fastener 7, and the other end projecting to the outside of the upper mold 2. Is inserted in the exhaust passage 6.

  The schematic sectional view of the resin fastener 7 is shown in FIG. 2 (a), and the schematic perspective view of the resin fastener 7 is shown in FIG. 2 (b).

  The resin fastener 7 has a vent 71 in the direction connecting the cavity 4 and the exhaust passage 6 at the time of mounting, and the outer diameter decreases from the end on the cavity 4 side to the end on the exhaust passage 6 side. It has a similar shape.

  In addition, a narrow diameter portion 72 having a diameter smaller than the outer diameter (maximum diameter) of the resin fastener 7 is formed at the end on the cavity 4 side, and on the exhaust passage 6 side of the narrow diameter portion 72, An extremely narrow diameter portion 73 whose diameter is smaller than that of the narrow diameter portion 72 is formed, and a constricted portion 74 is formed.

  In the casting mold 1 shown in FIG. 1, when the resin material is injected from the gate 5, the gas in the cavity 4 passes through the vent holes 71 of the resin fastener 7 and the exhaust tube 78 to form the upper mold 2. Exhausted outside. Also, the resin material excessively injected is discharged to the outside of the upper mold 2 through the vent holes 71 of the resin fastener 7 and the exhaust tube 78. Thereby, the inflow to the exhaust passage 6 of the resin material injected | poured excessively can be prevented.

  On the other hand, as the resin material is injected into the cavity 4, the resin material passes through the narrow diameter portion 72 formed at the end of the resin fastener 7 and enters the extremely narrow diameter portion 73. Then, filling of the resin material is completed in this state and the casting mold 1 is cooled, so that the resin material is cured and the resin fastener 7 becomes a part of a molded product and is integrated.

  As described above, in the molded product, the resin material covers the narrow diameter portion 72 formed in the resin fastener 7 and further enters the extremely narrow diameter portion 73 to be cured and integrated, so the resin fastener from the molded product 7 does not come off easily.

  Therefore, when the molded product is removed from the casting mold 1, the resin fastener 7 is detached from the upper mold 2 together with the molded product, and the resin fastener 7 does not remain in the upper mold 2. As a result, in the molding of a molded article using the casting mold 1 having the resin fastener 7, it is not necessary to remove the exhaust passage 6 and remove the resin fastener after molding of the molded article.

  The resin material used for molding the molded product is not particularly limited as long as it is a resin material that can be cast-molded, and thermoplastic resins and thermosetting resins can be used according to the molded product. As a thermoplastic resin, an acrylonitrile butadiene styrene resin (ABS resin), a polypropylene resin, etc. can be mentioned, for example. Moreover, as a thermosetting resin, a phenol resin, an epoxy resin, a melamine resin, a urea resin, unsaturated polyester resin etc. can be mentioned, for example. Among these, in view of moldability, durability and the like, an ABS resin can be suitably used.

  The size and shape of the resin fastener 7 are not particularly limited, and can be determined as appropriate depending on the shape of a portion to be a part of a molded product.

  Further, the material of the resin fastener 7 is not particularly limited, and examples thereof include metals and cured resins. The resin fastener 7 is preferably made of a material having high adhesion to the resin material injected into the cavity 4. As such a material, a resin cured product, in particular, an ABS resin cured product is more preferable. Further, in order to further increase the adhesion to the resin material, it is possible to form surface irregularities such as forming fine irregularities on the surface of the resin fastener 7 or making the surface matt.

  Further, the installation position of the exhaust passage 6, that is, the arrangement position of the resin fastener 7 is not particularly limited, but the surface of the resin product is a molded product because the resin fastener 7 is a part of the molded product. It is desirable to provide in the part which is hard to be recognized visually.

  Moreover, the part which the resin fastener 7 makes as a part of molded article can also be made into the rib as a reinforcement member of a molded article, and a part of attachment member of other members.

  In the casting mold 1 shown in FIG. 1, the resin fastener 7 is a part of an apron piece 9 for supporting an apron attached to the outer portion of the bathtub when the molded product is a bathtub. It is designed.

  The resin fastener 7 is used by removing the resin fastener 7 from the molded product taken out from the casting mold 1 using a material having low adhesiveness to the resin material injected into the cavity 4 as the resin fastener 7. You may do so. In this case, the resin fastener 7 is selected and used such that the adhesion between the resin fastener 7 and the resin material is higher than the adhesion between the resin fastener 7 and the casting mold 1.

  FIG. 3 shows a back perspective view of the bathtub 10 molded using the casting mold 1 of FIG. As shown in FIG. 3, the resin fastener 7 is integrated as a part of an apron piece 9 for supporting the apron.

  FIG. 4 shows a partial cross-sectional view of a state in which the apron 11 is held in the bath 10, and FIG. 5 is a perspective view in a state in which the apron 11 is held in the bath 10. In the present embodiment, the hanging portion 8 provided at the upper end of the apron 11 is provided at the end of the flange 14 formed at the edge of the bathtub 15, and the spacing from the hanging portion 8 to the bathtub 15 side , And is inserted between the apron piece 9 including the resin fastener 7 and provided.

  Further, the folded back portion 12 of the apron 11 inserted between the hanging piece 8 and the apron piece 9 is pressed against the apron piece 9 by the fixing member 13 and held.

  As described above, by integrating the resin fastener 7 as a part of the member of the molded article, the back side of the bathtub of the molded article can be simply designed.

  As mentioned above, although the cast molding die 1 of this invention was demonstrated based on embodiment, the cast molding die 1 of this invention is not limited to said embodiment, It does not deviate from the summary. Various modifications are possible within the scope.

  For example, although the resin fastener 7 is described as the cast molding die 1 for molding the bath 10 in the above embodiment, the cast molding die 1 of the present invention is a mold that can be molded by cast molding. It can be applied without limitation to the molding of the product.

  Further, in the above embodiment, the resin fastener 7 is applied to the casting mold 1 having the exhaust passage 6 in the upper mold 2, but for cast molding in which the exhaust passage 6 is provided to the lower mold 3 It is also possible to apply the resin fastener 7 to the mold 1.

  In the above embodiment, although the shape of the resin fastener 7 is a cylindrical shape having a thin tip, the resin fastener 7 has a quadrangular prism or a complicated cross section depending on the function or design of a part to be a part of a molded product. It is also possible to use a resin fastener 7.

1 Injection molding mold 2 Upper mold 3 Lower mold 4 Cavity 6 Exhaust path 7 Resin fastener 71 Air hole 72 Narrow diameter portion 73 Extreme narrow diameter portion 74 Narrow portion

Claims (2)

A casting molding metal comprising a cavity for resin molding between an upper mold and a lower mold, and at least one of the upper mold and the lower mold being provided with an exhaust passage for discharging a gas in the cavity. Type and
At a portion where the exhaust passage and the cavity are in contact, a vent hole is provided in the direction connecting the cavity and the exhaust passage, gas in the cavity is exhausted through the vent hole, and the resin material flows into the exhaust passage. Equipped with plastic fasteners to prevent
A narrow diameter portion having a diameter smaller than the outer diameter of the resin fastener is formed at an end of the resin fastener on the cavity side, and the diameter is larger than that of the narrow diameter portion on the exhaust passage side of the narrow diameter portion. A small extremely narrow diameter portion is formed, and a narrow portion into which the resin material formed by the difference in diameter of the narrow diameter portion and the extremely narrow diameter portion is inserted ,
A cast molding die characterized in that the resin retaining portion becomes a part of a molded product by curing of the resin material which has entered the narrow portion after molding. The casting mold according to claim 1, wherein the resin fastener is formed of a cured ABS resin .

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