US-20260124800-A1 - METHOD FOR PRODUCING RESIN VESSEL MADE OF RESIN, MOULD UNIT AND MOULDING APPARATUS

US20260124800A1US 20260124800 A1US20260124800 A1US 20260124800A1US-20260124800-A1

Abstract

A mold unit to be used for a temperature adjustment step of a preform, the mold unit including a cavity mold configured to accommodate therein a bottomed preform made of resin, and an air introduction member configured to be in airtight contact with the preform and to supply air into the preform. The air introduction member has a blowing port through which the air is to be supplied to an inside of the preform and a discharge port through which the air is to be discharged to an outside of the preform.

Inventors

Ryo Kawamura
Manabu OGIHARA
Junji Takahashi

Assignees

NISSEI ASB MACHINE CO., LTD.

Dates

Publication Date: 20260507
Application Date: 20251229
Priority Date: 20171019

Claims (7)

1 . A mold unit to be used for a temperature adjustment step of a preform, the mold unit comprising: a cavity mold configured to accommodate therein a bottomed preform made of resin, and an air introduction member configured to be in airtight contact with the preform and to supply air into the preform, wherein the air introduction member has: a blowing port through which the air is to be supplied to an inside of the preform; and a discharge port through which the air is to be discharged to an outside of the preform.
2 . The mold unit according to claim 1 , wherein the cavity mold has a fixed-type structure and is not a split mold.
3 . The mold unit according to claim 1 , wherein the air is supplied from the blowing port of the introduction member into the inside of the preform such that the air is in physical contact with the inside of the preform.
4 . A blow molding machine comprising: an injection molding part; a temperature adjustment part; and a blow molding part, wherein the temperature adjustment part comprises the mold unit according to claim 1 .
5 . An apparatus for manufacturing a container made of resin, the apparatus comprising at least: an injection molding part configured to injection mold a bottomed preform made of resin; a temperature adjustment part configured to adjust a temperature of the preform manufactured by the injection molding part; and a blow molding part configured to blow mold the preform whose temperature has been adjusted to manufacture the container made of resin, wherein the injection molding part is configured to: inject a resin material into a space having a shape of the preform, the space being formed by mold-clamping an injection molding mold; and cool the resin material inside the space after the injection of the resin material has been completed, and wherein a time during which the resin material is cooled in the space after the injection of the resin material has been completed is half or less of a time during which the resin material is injected.
6 . The apparatus for manufacturing a container made of resin according to claim 5 , wherein the time during which the resin material is cooled in the space after the injection of the resin material has been completed is ⅖ or less of the time during which the resin material is injected.
7 . The apparatus for manufacturing a container made of resin according to claim 5 , wherein the time during which the resin material is cooled in the space after the injection of the resin material has been completed is 0.43 times or less of the time during which the resin material is injected.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This is a Divisional of U.S. patent application Ser. No. 17/580,260, filed Jan. 20, 2022, which is a Continuation of U.S. patent application Ser. No. 16/516,128, filed Jul. 18, 2019 now U.S. Pat. No. 11,260,575, issued Mar. 1, 2022, which is a continuation of International Pat. Appl. No. PCT/JP2018/039007, filed Oct. 19, 2018, which claims the benefit of Japanese Pat. Appl. No. 2017-202716, filed Oct. 19, 2017. The disclosure of each of the above-mentioned documents, including the specification, drawings, and claims, is incorporated herein by reference in its entirety. TECHNICAL FIELD The present invention relates to a method for manufacturing a container made of resin, a mold unit and a molding machine. BACKGROUND ART A hot parison blow molding method is a method of performing blow molding by using potential heat upon injection molding of a preform, and can manufacture a variety of containers having better aesthetic appearances, as compared to a cold parison method. A hot parison blow molding machine includes a machine (4-stage type) having a temperature adjustment part provided between an injection molding part and a blow molding part and a machine (2-stage type and 3-stage type) having no temperature adjustment part. When the temperature adjustment part is provided, it is generally easy to adjust a temperature condition of a preform before blow to a condition suitable for shaping of a final container. As regards the hot parison blow molding machine, diverse methods and apparatuses for shortening a molding cycle have been developed. For example, in order to shorten the molding cycle, Patent Literature 1 and Patent Literature 2 disclose shortening times relating to mold opening and closing operations of an injection mold and raising and lowering operations of an extension apparatus, Patent Literature 3 discloses changing a control method for an injection apparatus, and Patent Literature 4 discloses adopting a preform shape which can be demolded at an early stage and an injection molding mold therefor. CITATION LIST Patent Literature Patent Literature 1: JP-A-2005-007797Patent Literature 2: International Publication No. 2016/148189Patent Literature 3: International Publication No. 2017/002150Patent Literature 4: International Publication No. 2017/098673 SUMMARY OF INVENTION Technical Problem In recent years, it is desired to further improve productivity of the hot parison blow molding machine, specifically, to further shorten the molding cycle time. In order to shorten the molding cycle time, it is required to shorten the operating time at the machine-side, as disclosed in Patent Literature 1 to Patent Literature 3. However, as disclosed in Patent Literature 4, the vital point is to shorten injection molding time (cooling time) of the preform, which is a rate-controlling step. However, in Patent Literature 4, it is essential to adopt a special preform shape. Since the preform should be designed to have an optimal shape (thickness distribution) corresponding to a container shape, Patent Literature 4 can cope with only the molding of some containers and cannot be said to have high general versatility. Particularly, the method disclosed in Patent Literature 4 cannot cope with the molding of a cosmetic container (a thick container) advantageous to the hot parison method. Like this, in the hot parison blow molding method, a cycle shortening method having high general versatility, considering diverse molding situations, has not been devised at present. It is therefore an object of the present invention to provide a method for manufacturing a container made of resin, a mold unit and a molding machine capable of favorably molding a final molded article while shortening a molding cycle. Solution to Problem A method for manufacturing a container made of resin of the present disclosure capable of solving the above-described problem: an injection molding step of injection molding a bottomed preform made of resin;a temperature adjustment step of adjusting a temperature of the preform manufactured in the injection molding step, anda blow molding step of blow molding the preform whose temperature has been adjusted to manufacture the container made of resin,wherein in the temperature adjustment step, the preform is accommodated in a cavity mold,an air introduction member is brought into airtight contact with the preform, andair is supplied from a blowing port of the air introduction member into the preform, and the air is discharged from a discharge port of the air introduction member to an outside of the preform, so that the preform is in close contact with an inner wall of the cavity mold and is cooled. According to the above configuration, the preform can be cooled from an inner side thereof in the temperature adjustment step, so that it is possible to favorably mold a final molded article while shortening a molding cycle. In the method for manufacturing a container made o