A mold apparatus for forming a molded part includes a mold body, a mold cavity formed in said mold body, a plurality of valve gates associated with said mold body, and a controller in communication with said plurality of valve gates. The controller is programmed to time opening of each valve gate based on a selected flow rate required to eliminate weld lines in the product.

An injection molding device includes an injection machine, a molding die, and a high frequency oscillation device. The injection machine injects a resin material containing a dielectric heat generating material while keeping fluidity by temperature control. The molding die includes a cavity being a channel of flow of the resin material, and a pair of electrodes, each of which faces the cavity, the pair of electrodes being disposed to sandwich the resin material therebetween in a direction crossing a direction of the flow. The high frequency oscillation device applies a high frequency alternate-current voltage to the pair of electrodes.

An injection molding device includes an injection machine, a molding die, and a high frequency oscillation device. The injection machine injects a resin material containing a dielectric heat generating material while keeping fluidity by temperature control. The molding die includes a cavity being a channel of flow of the resin material, and a pair of electrodes, each of which faces the cavity, the pair of electrodes being disposed to sandwich the resin material therebetween in a direction crossing a direction of the flow. The high frequency oscillation device applies a high frequency alternate-current voltage to the pair of electrodes.

A control device for an injection molding machine including a cylinder into which a resin is supplied and a screw that moves forward and rearward and rotates inside the cylinder, includes a metering control unit that performs metering of the resin inside the cylinder by controlling forward rotation and rearward movement of the screw until the screw has been moved rearward to a predetermined metering position, based on predetermined metering conditions, a rearward movement speed acquisition unit acquiring a rearward movement speed of the screw, a speed determination unit that determines a suck back speed for causing a resin pressure to reach a target pressure, based on the rearward movement speed acquired during metering by the rearward movement speed acquisition unit, and a suck back control unit causing the screw to move further rearward based on the suck back speed, after the screw has reached the predetermined metering position.

A control device for an injection molding machine including a cylinder into which a resin is supplied and a screw that moves forward and rearward and rotates inside the cylinder, includes a metering control unit that performs metering of the resin inside the cylinder by controlling forward rotation and rearward movement of the screw until the screw has been moved rearward to a predetermined metering position, based on predetermined metering conditions, a rearward movement speed acquisition unit acquiring a rearward movement speed of the screw, a speed determination unit that determines a suck back speed for causing a resin pressure to reach a target pressure, based on the rearward movement speed acquired during metering by the rearward movement speed acquisition unit, and a suck back control unit causing the screw to move further rearward based on the suck back speed, after the screw has reached the predetermined metering position.

A material delivery device includes: a plasticization unit having a screw and configured to plasticize a material by rotation of the screw to produce a plasticized material; a flow path through which the plasticized material flows; a nozzle having a nozzle opening that communicates with the flow path and delivers the plasticized material to an outside; a cylinder coupled to the flow path; a rod inserted into the cylinder; and a first pressure detection unit configured to detect a pressure of the plasticized material in the flow path via the rod. In a longitudinal direction of the rod, the rod has a rod end surface facing the flow path and a transmission unit at an opposite side of the rod end surface, and transmits a force due to the pressure received at the rod end surface to the first pressure detection unit via the transmission unit.

A material delivery device includes: a plasticization unit having a screw and configured to plasticize a material by rotation of the screw to produce a plasticized material; a flow path through which the plasticized material flows; a nozzle having a nozzle opening that communicates with the flow path and delivers the plasticized material to an outside; a cylinder coupled to the flow path; a rod inserted into the cylinder; and a first pressure detection unit configured to detect a pressure of the plasticized material in the flow path via the rod. In a longitudinal direction of the rod, the rod has a rod end surface facing the flow path and a transmission unit at an opposite side of the rod end surface, and transmits a force due to the pressure received at the rod end surface to the first pressure detection unit via the transmission unit.

In one aspect, a method of molding a multilayer article comprises causing a surface layer material injection unit to commence injecting a surface layer material into a mold cavity via a surface layer material channel. Then, an internal layer material injection unit commences injecting an internal layer material into the mold cavity an internal layer material channel. Then, during application of a hold pressure upon the surface layer material in the surface layer material channel and with the surface and internal layer material injection units in fluid communication with one another, a pullback stroke is effected at the internal layer material injection unit. After a delay interval, at least one physical parameter indicative of a post-pullback pressure of the internal layer material is detected, and an indicator of pullback effectiveness is generated based on the post-pullback pressure indicated by the at least one physical parameter relative to a threshold pressure.

In one aspect, a method of molding a multilayer article comprises causing a surface layer material injection unit to commence injecting a surface layer material into a mold cavity via a surface layer material channel. Then, an internal layer material injection unit commences injecting an internal layer material into the mold cavity an internal layer material channel. Then, during application of a hold pressure upon the surface layer material in the surface layer material channel and with the surface and internal layer material injection units in fluid communication with one another, a pullback stroke is effected at the internal layer material injection unit. After a delay interval, at least one physical parameter indicative of a post-pullback pressure of the internal layer material is detected, and an indicator of pullback effectiveness is generated based on the post-pullback pressure indicated by the at least one physical parameter relative to a threshold pressure.

An injection molding apparatus (10) comprising an actuator (940, 941, 942) comprised of a driver (940dr, 941dr, 942dr) receiving electrical energy or power from an electrical drive (940d, 941d, 942d), the electrical drive (940d, 941d, 942d) comprising an interface that receives and controllably distributes electrical energy or power in controllably varied amounts during the course of an injection cycle to the driver (940dr, 941dr, 942dr), the electrical drive (940d, 941d, 942d) being housed within or by an actuator housing (940h, 941h, 942h) or being mounted on or to the housing (940h, 941h, 942h), the housing (940h, 941h, 942h) and the electrical drive (940d, 941d, 942d) being mounted on, to or in close proximity to the heated manifold (40), a cooling device (940mc, 940mc1, 940mc2, 941mc, 942mc) disposed between the heated manifold (40) and the housing (940h, 941h, 942h) adapted to substantially isolate or insulate at least the electrical drive (940d, 941d, 942d) from substantial communication with heat emanating or emitted from the heated manifold (40).