[Problems] The objective of present invention is to provide the mold, injection molding system and method capable of limiting the outflow of pressurized fluid injected into a mold cavity. [Solution] A mold device and a molding device comprising: a shaft body 27 provided at least on one mold among a first mold 205 and a second mold 206 that form a molding space 200, the shaft body being used for pushing out a molded article formed from a resin injected into the molding space 200; a ring-shaped elastic member for supporting the shaft body 27 in which an opening formed along the circumferential direction is oriented toward the said molding space; and an injection portion provided on at least one mold among the first mold 205 and the second mold 206, the injection portion being used for injecting a pressurized fluid into the molding space 200.

A method for producing a three-dimensionally shaped trim part of a motor vehicle, which has a visible side and a mounting side. A flowable material is injected with pressure into a chamber of an injection molding tool, which has at least two mold shells, which, when assembled, form the chamber with a negative mold of the trim part, wherein at least one first of the mold shells forms the visible side and at least one second of the mold shells forms the mounting side of the trim part. The material is hardened in the chamber. A gas pressure is generated that acts in a planar manner between the second mold shell and the material during the hardening. The hardened material is removed as a trim part from the chamber of the injection molding tool.

A mold device where a pressurized fluid is injected into a clearance between a resin injected into a cavity and a cavity wall surface, the mold device including: a shaft body provided on at least one of a first mold and a second mold, the first mold and the second mold forming a molding space, the shaft body ejecting a molded article molded from the resin injected into the molding space; a ring-shaped elastic member for supporting and sealing the shaft body, an opening of a groove formed in the ring-shaped elastic member along a circumferential direction of the ring-shaped elastic member being oriented toward the molding space, a load being applied on the ring-shaped elastic member to improve adhesion to the shaft body; and an injection portion provided on at least one of the first mold and the second mold for injecting the pressurized fluid into the molding space.

A method is provided to fabricate an injection molded piece with a weakened portion in an injection molding system having a cavity defined by a fixed mold part and a moveable mold part. The method comprises injecting raw material in a liquid state into the cavity to form the injection molded piece; moving a weakening insert into the injection molded piece from a first surface of the injection molded piece; injecting a gas to the first surface of the injection molded piece with a controlled pressure, wherein moving the weakening insert into the injection molded piece and injecting the gas are performed while the injection molded piece is in the liquid state.

[Problem] The present invention relates to a manufacturing method for obtaining a molded article having an expanded layer in the molded article, wherein an expanding agent and device used to manufacture a resin having expansion properties, and a means for increasing expansion ratio are provided.

[Solution] In the present invention, an expanding agent placed in a heating cylinder of a molding machine is configured as a liquid, the volume of the expanding agent is controlled, and the expanding agent is injected into a molten resin in the heating cylinder of the molding machine. The volume of the injected expanding agent can thereby be accurately measured each time. When a low-boiling liquid such as water, an alcohol, or an ether is used as the injected expanding agent, all of the liquid is vaporized by the temperature of the heating cylinder of the molding machine, and no residue thereof is therefore left in the molded article. When sodium bicarbonate water is used as the injected expanding agent, solvent water vaporizes and water vapor also becomes expandable gas, which is less expensive than using sodium bicarbonate as the expanding agent for a master batch using the resin that is to be molded.

An injection molded article obtained by injection molding a thermoplastic resin composition comprising 100 parts by mass of a thermoplastic resin and 50 parts by mass or less of at least one of a filler and a colored metallic pigment, wherein at least one weld exists, and a long diameter of 95% by mass or more of the filler existing within a cross-sectional depth of 50 μm or less from a surface of the weld is parallel to the surface of the weld.

A holding portion having a diameter larger than that of a cavity is formed in communication with the cavity, in an area of a two-part type mold, the area including a portion corresponding to an annular groove. Subsequently, an insert member formed in a cylindrical shape and provided with, on an outer circumferential surface, the annular groove having no step in a groove surface is fitted to the holding portion, and then the mold is closed. On an inner circumferential surface of the insert member, a surface treatment layer having a surface roughness rougher than those of other portions of the insert member is formed. Molten resin is injected into the cavity; thereafter, an assist material is injected into the cavity to mold the resin into a desired pipe body. Then, the insert member and the pipe body are integrated along with curing of the resin.

A controller for an injection molding system is in communication with a melt flow control unit, a gas assist control unit, and a gas counter pressure control unit. The controller can effect real-time adjustments to gas assist pressure and/or gas counter pressure as a function of melt pressure or flow front position.

A holding portion having a diameter larger than that of a cavity is formed in communication with the cavity, in an area of a two-part type mold, the area including a portion corresponding to an annular groove. Subsequently, an insert member formed in a cylindrical shape and provided with, on an outer circumferential surface, the annular groove having no step in a groove surface is fitted to the holding portion, and then the mold is closed. On an inner circumferential surface of the insert member, a surface treatment layer having a surface roughness rougher than those of other portions of the insert member is formed. Molten resin is injected into the cavity; thereafter, an assist material is injected into the cavity to mold the resin into a desired pipe body. Then, the insert member and the pipe body are integrated along with curing of the resin.

A controller for an injection molding system is in communication with a melt flow control unit, a gas assist control unit, and a gas counter pressure control unit. The controller can effect real-time adjustments to gas assist pressure and/or gas counter pressure as a function of melt pressure or flow front position.