A control method of an injection molding machine that molds a molding product including a skin layer and a core layer in a mold unit by injecting a molding material to the mold unit from a nozzle, the control method including controlling, at a starting time of an injection process, a temperature of the molding material used to form the skin layer so as to be higher than a temperature of the molding material used to form the core layer.

A method and apparatus for injection molding of plastic material into a cavity of a mold by means of at least one injector whose opening and closing occurs through an electronic control unit and wherein an undesired opening of the mold caused by any overpressure of the plastic material injected into the cavity of the mold is detected by means of transducers and corrected by means of the electronic control unit. The transducers are arranged outside the cavity of the mold.

A method and apparatus for injection molding of plastic material into a cavity of a mold by means of at least one injector whose opening and closing occurs through an electronic control unit and wherein an undesired opening of the mold caused by any overpressure of the plastic material injected into the cavity of the mold is detected by means of transducers and corrected by means of the electronic control unit. The transducers are arranged outside the cavity of the mold.

To provide a new foam molding method and injection molding machine capable of solving variation in a wall thickness and a foamed state, sensor corrosion, a complexity of sensor positioning, and the like. The above-described problem is solved by a foam molding method comprising a resin filling step of filling a mold (2), clamped by a predetermined mold clamping force (Pc), with a resin (R) at a predetermined molding injection pressure (Pi), a filling stopping step of stopping the filling of the resin (R) when, while monitoring a mold gap (Lm) of the mold (2) during the filling, a predetermined mold gap value set in advance is reached, a surface layer curing and filled resin cooling step of curing a surface layer of the resin (R) for a certain time and cooling the filled resin (R) for a certain time after the filling of the resin (R) is stopped, a volume controlling step of controlling a volume increase by reducing the mold clamping force after curing the surface layer of the resin (R) for a certain time, and a taking out step of taking out a foam-molded product by opening the mold (2) after the volume control is performed and after cooling the filled resin (R) for a certain time.

To provide a new foam molding method and injection molding machine capable of solving variation in a wall thickness and a foamed state, sensor corrosion, a complexity of sensor positioning, and the like. The above-described problem is solved by a foam molding method comprising a resin filling step of filling a mold (2), clamped by a predetermined mold clamping force (Pc), with a resin (R) at a predetermined molding injection pressure (Pi), a filling stopping step of stopping the filling of the resin (R) when, while monitoring a mold gap (Lm) of the mold (2) during the filling, a predetermined mold gap value set in advance is reached, a surface layer curing and filled resin cooling step of curing a surface layer of the resin (R) for a certain time and cooling the filled resin (R) for a certain time after the filling of the resin (R) is stopped, a volume controlling step of controlling a volume increase by reducing the mold clamping force after curing the surface layer of the resin (R) for a certain time, and a taking out step of taking out a foam-molded product by opening the mold (2) after the volume control is performed and after cooling the filled resin (R) for a certain time.

A clamping device (14) comprises a pressure receiving platen (24), a stationary platen (20), a movable platen (22), a toggle mechanism (28), and a drive device (37). A first position detector (38a) detects the operation amount of the movable platen (22) based on the position of a crosshead (26); a pressure detector (35) detects the actual clamping force of a mold (19); and a second position detector (43) detects the actual position of the movable platen (22). A control portion (50) has first correction means correcting the operation amount of the movable platen (22) at the time of a minute mold opening operation based on the actual clamping force and on the set clamping force, and second correction means correcting the operation amount of the movable platen (22) at the time of the minute mold opening operation based on the operation amount of the movable platen (22) and on the position of the movable platen (22).

A clamping device (14) comprises a pressure receiving platen (24), a stationary platen (20), a movable platen (22), a toggle mechanism (28), and a drive device (37). A first position detector (38a) detects the operation amount of the movable platen (22) based on the position of a crosshead (26); a pressure detector (35) detects the actual clamping force of a mold (19); and a second position detector (43) detects the actual position of the movable platen (22). A control portion (50) has first correction means correcting the operation amount of the movable platen (22) at the time of a minute mold opening operation based on the actual clamping force and on the set clamping force, and second correction means correcting the operation amount of the movable platen (22) at the time of the minute mold opening operation based on the operation amount of the movable platen (22) and on the position of the movable platen (22).

A misalignment sensing system for a molding structure and a method for using same. The molding structure includes a first component and a second component, at least one of the components being selectively repositionable between a closed configuration of the mold structure and an open configuration of the mold structure. The misalignment sensing system includes an alignment member including a male portion coupled to and extending from the first component of the molding structure, and a female portion defined in the second component of the molding structure, the female portion being configured to receive the male portion when the molding structure is in a closed configuration; and at least one sensor connected to one of the male and female portions and being configured to detect a deformation of any one of the male portion and the female portion, the deformation being induced by a misalignment of the molding structure.

A misalignment sensing system for a molding structure and a method for using same. The molding structure includes a first component and a second component, at least one of the components being selectively repositionable between a closed configuration of the mold structure and an open configuration of the mold structure. The misalignment sensing system includes an alignment member including a male portion coupled to and extending from the first component of the molding structure, and a female portion defined in the second component of the molding structure, the female portion being configured to receive the male portion when the molding structure is in a closed configuration; and at least one sensor connected to one of the male and female portions and being configured to detect a deformation of any one of the male portion and the female portion, the deformation being induced by a misalignment of the molding structure.

The production of multicomponent parts (4) which include a functional part (3), in particular a hollow needle, onto which a plastic molding (2), in particular a syringe barrel (2), is molded. In order to be able to convert the injection molding device quickly and conveniently, the device has a changing device (11), by which it is possible optionally to move functional part holders (7, 8, 9), matched to different types of functional parts, and/or a functional part holder (8) and a placeholder element (10) into the use position thereof in front of a mold cavity (6) of the injection mold (5) of the injection molding device (1).