Method for manufacturing resin container part, mold unit, and blow molding machine including the mold unit

Patent metadata

Field	Value
Publication number	US-11235504-B2
Application number	US-201916963955-A
Country	US
Kind code	B2
Filing date	Jan 24, 2019
Priority date	Jan 26, 2018
Publication date	Feb 1, 2022
Grant date	Feb 1, 2022

Abstract

A method for manufacturing a resin container part includes: injection-molding of a bottomed resin preform including, on a bottom portion thereof, a thick bulging portion that retains residual heat by which the bulging portion is deformable by being pressed to follow a shape of a blow cavity mold; and a blowing including stretching a body portion of the preform by applying a blow pressure to the preform and forming a joint portion by pressing the bulging portion of the preform with an upper bottom mold to deform the bulging portion to follow the shape of the blow cavity mold.

First claim

The invention claimed is:

1. A method for manufacturing a resin container part, the method comprising:
injection-molding of a bottomed resin preform including, on a bottom portion thereof, a thick bulging portion that retains residual heat by which the bulging portion is deformable by being pressed to follow a shape of a blow cavity mold; and
blowing including stretching of a body portion of the preform by applying a blow pressure to the preform and forming a joint portion by pressing the bulging portion of the preform with an upper bottom mold to deform the bulging portion to follow the shape of the blow cavity mold
wherein, during the injection-molding, the preform is formed by injecting a resin into a space formed by at least an injection core mold and an injection cavity mold,
wherein, after the injection-molding, the preform and the injection core mold are accommodated in the blow cavity mold, and
wherein, during the blowing, air is introduced from the injection core mold to stretch the body portion of the preform.

2. The method for manufacturing a resin container part according to claim 1 ,
wherein the injection core mold includes
a first core mold that defines a shape of an inner surface of each of the body portion and the bottom portion of the preform,
a second core mold that defines an inner surface of an opening portion of the preform, and
an air outlet that is provided in a boundary region between outer peripheries of the first core mold and the second core mold, and

wherein, during the blowing, the air is introduced from the air outlet to stretch the body portion of the preform.

3. The method for manufacturing a resin container part according to claim 1 ,
wherein, during the blowing, the first core mold is moved up and down to increase the size or decrease the size of the air outlet.

4. A mold unit comprising at least:
an injection molding mold for use in an injection-molding of a bottomed resin preform; and
a blow molding mold for use in a blow-molding of the preform to manufacture a resin container part,
wherein the injection molding mold includes
an injection core mold that defines an inner shape of the preform, and
an injection cavity mold that defines an outer shape of the preform,

wherein the injection cavity mold is provided with a bulging portion forming part for forming a thick bulging portion on a bottom portion of the preform,
wherein the blow molding mold includes
a blow cavity mold that defines an outer shape of the container part, and
an upper bottom mold that is movable up and down toward the bulging portion of the preform,

wherein the blow cavity mold is provided with a joint portion forming part for forming a joint portion at a bottom portion of the container part by pressing the bulging portion with the upper bottom mold, and
wherein the injection core mold includes an air outlet.

5. A mold unit comprising at least:
an injection molding mold for use in an injection-molding of a bottomed resin preform; and
a blow molding mold for use in a blow-molding of the preform to manufacture a resin container part,
wherein the injection molding mold includes
an injection core mold that defines an inner shape of the preform, and
an injection cavity mold that defines an outer shape of the preform,

wherein the injection cavity mold is provided with a bulging portion forming part for forming a thick bulging portion on a bottom portion of the preform,
wherein the blow molding mold includes
a blow cavity mold that defines an outer shape of the container part, and
an upper bottom mold that is movable up and down toward the bulging portion of the preform,

wherein the blow cavity mold is provided with a joint portion forming part for forming a joint portion at a bottom portion of the container part by pressing the bulging portion with the upper bottom mold, and
wherein the injection core mold includes
a first core mold that defines a shape of an inner surface of each of a body portion and the bottom portion of the preform,
a second core mold that defines an inner surface of an opening portion of the preform, and
an air outlet that is provided in a boundary region between outer peripheries of the first core mold and the second core mold.

6. The mold unit according to claim 5 ,
wherein the first core mold is configured to be movable up and down to increase the size or reduce the size of the air outlet.

7. A blow molding machine comprising the mold unit according to claim 4 .

Assignees

• Nissei Asb Machine Co Ltd

Inventors

• Takehana Daizaburo

Classifications

• B29C2049/4881

  having a mandrel or core e.g. two mould halves with a core in-between · CPC title

• B29C49/0665

  the injection mould cavity and the blow-mould cavity being displaceable to the geometrically fixed injection core mould · CPC title

• B29C49/063

  with the parison axis held in the plane of rotation · CPC title

• B29L2031/7132

  Bowls, Cups, Glasses · CPC title

• B29C2049/023

  using inherent heat of the preform, i.e. 1 step blow moulding · CPC title