As an injection screw 2 applies pressure, a holding pressure plunger 22 is moved backward under the pressure of a resin to flow the resin into a holding pressure path 9, and the resin in a resin path 6 is pressurized (primary holding pressure process). A shutoff plunger 12 is closed, and the resin in the resin path 6 and the holding pressure path 9 is pressurized by the holding pressure plunger 22 (secondary holding pressure process). Further, the shutoff plunger 12 is opened, and the holding pressure plunger 22 is moved forward until its tip projects into the resin path 6 to discharge all the resin in the holding pressure path 9 to the resin path 6, whereby the resin beside the injection screw 2 as compared with the shutoff plunger 12 is held with respect to the holding pressure path 9.

A plasticizing process in which a molten resin that has been plasticized and dissolved in a foaming gas is sent to the front end side of a heating cylinder (20) by means of a screw (21) that rotates in a heating cylinder (20), and the screw (21) retreats according as the molten resin accumulates in the front end side of the heating cylinder (20); a transfer process in which the screw (21) is advanced with rotating and transfers the molten resin accumulated in the front end side of the heating cylinder (20) from a plasticizing unit (2) to an injection unit (3), and an injection process in which the molten resin is injected from the injection unit (3) are conducted and repeated to produce a foamable injection molded product.

A plasticizing process in which a molten resin that has been plasticized and dissolved in a foaming gas is sent to the front end side of a heating cylinder (20) by means of a screw (21) that rotates in a heating cylinder (20), and the screw (21) retreats according as the molten resin accumulates in the front end side of the heating cylinder (20); a transfer process in which the screw (21) is advanced with rotating and transfers the molten resin accumulated in the front end side of the heating cylinder (20) from a plasticizing unit (2) to an injection unit (3), and an injection process in which the molten resin is injected from the injection unit (3) are conducted and repeated to produce a foamable injection molded product.

An abnormality detection device for detecting an abnormality of a movable part provided in an injection molding machine includes: a through hole formed in the movable part or in an adjacent member arranged adjacent to the movable part; and a microphone installed inside the through hole to collect sound generated by the movement of the movable part.

A monolithic injection molded plastic part including an interior core, a surface formed as a monolithic structure with the interior core, and a distribution of hollow cells formed within the interior core during an injection molding process from a blowing agent and methods for making the same are provided. Such methods include preparing a mixture of unmelted plastic resin, filler agent, and blowing agent, melting the mixture into a viscous combination using a standard injection molding machine, injecting a set amount of the viscous combination into a hollow cavity of an injection mold secured within the standard injection molding machine, and holding the set amount of the viscous combination in the hollow cavity at a low pressure for a hold time until the viscous combination sets into a monolithic structure at least partially filling the hollow cavity and the blowing agent forms a distribution of hollow cells throughout the monolithic structure.

A monolithic injection molded plastic part including an interior core, a surface formed as a monolithic structure with the interior core, and a distribution of hollow cells formed within the interior core during an injection molding process from a blowing agent and methods for making the same are provided. Such methods include preparing a mixture of unmelted plastic resin, filler agent, and blowing agent, melting the mixture into a viscous combination using a standard injection molding machine, injecting a set amount of the viscous combination into a hollow cavity of an injection mold secured within the standard injection molding machine, and holding the set amount of the viscous combination in the hollow cavity at a low pressure for a hold time until the viscous combination sets into a monolithic structure at least partially filling the hollow cavity and the blowing agent forms a distribution of hollow cells throughout the monolithic structure.

A monolithic injection molded plastic part including an interior core, a surface formed as a monolithic structure with the interior core, and a distribution of hollow cells formed within the interior core during an injection molding process from a blowing agent and methods for making the same are provided. Such methods include preparing a mixture of unmelted plastic resin, filler agent, and blowing agent, melting the mixture into a viscous combination using a standard injection molding machine, injecting a set amount of the viscous combination into a hollow cavity of an injection mold secured within the standard injection molding machine, and holding the set amount of the viscous combination in the hollow cavity at a low pressure for a hold time until the viscous combination sets into a monolithic structure at least partially filling the hollow cavity and the blowing agent forms a distribution of hollow cells throughout the monolithic structure.

Moulding assembly (100) with an inlet (117) for receiving raw material to be ejected, a barrel (112) for gathering and processing the raw material received through the inlet (117), a screw (110) for engaging the raw material in the barrel, a first drive unit (170) configured for rotating the screw (110) in order to grind the raw material into liquid form, where the moulding assembly further comprises a second drive unit (120) configured to displace the screw (110) in a direction essentially perpendicular to the rotation direction in and out of the barrel (112) depending on the pressure in the barrel (112).

A toggle lever clamping unit for an injection molding machine includes fixed and movable platens, a support plate, a toggle lever mechanism operatively connected with both the support plate and the movable platen, a cross clamp operatively connected with the toggle lever mechanism and movable along a machine longitudinal axis, and an electric drive for moving the cross clamp. In addition, a hydraulic drive is operatively connected with the cross clamp and includes a fluid-operated piston cylinder system, with the lengths of the cylinder and the piston rod being coordinated with one another such that the hydraulic drive follows a travel path of the cross clamp as the movable platen travels between an open position of the clamping unit, in which the toggle lever mechanism is swung in, and a closed position in which the toggle lever mechanism assumes a predeterminable extended position and a clamping force is built up.

Injection molding plastic parts includes furnishing resin material to a screw barrel having a rotatable screw therewithin, rotating the screw to work the resin material into a molten state, furnishing additive such as liquid color or another additive to the screw barrel interior at a first rate during screw rotation and driving the screw longitudinally from a first position to a second position to force an additive-resin material mixture resulting from screw rotation into a mold while furnishing additive with resin to the screw barrel interior at a second additive addition rate.