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.

An apparatus for controlling the rate of flow of mold material to a mold cavity, the apparatus comprising: an injection molding machine and a manifold; an actuator interconnected to a valve pin having a tip end; a valve system in fluid communication with the actuator to drive the actuator at one or more rates of travel, the valve system having a start position, one or more intermediate drive rate positions and a high drive rate position, the start position holding the valve pin in a gate closed position; a controller that instructs the valve system to move from the start position to the one or more intermediate drive rate positions and to remain in the one or more intermediate drive rate positions for one or more corresponding predetermined amounts of time.

An apparatus for controlling the rate of flow of a fluid mold material comprising: a manifold, an actuator interconnected to a valve pin, a position sensor that senses position of the valve pin, a controller that controls movement of the actuator according to instructions that instruct the actuator to drive the valve pin upstream at one or more selected intermediate velocities in response to receipt by the controller of a signal from the position sensor that the valve pin is disposed in the one or more intermediate upstream gate open positions.

An apparatus for controlling the rate of flow of a fluid mold material comprising: a manifold, an actuator interconnected to a valve pin, a position sensor that senses position of the valve pin, a controller that controls movement of the actuator according to instructions that instruct the actuator to drive the valve pin upstream at one or more selected intermediate velocities in response to receipt by the controller of a signal from the position sensor that the valve pin is disposed in the one or more intermediate upstream gate open positions.

An apparatus for controlling the rate of flow of mold material to a mold cavity, the apparatus comprising: an injection molding machine and a manifold; an actuator interconnected to a valve pin having a tip end; a valve system in fluid communication with the actuator to drive the actuator at one or more rates of travel, the valve system having a start position, one or more intermediate drive rate positions and a high drive rate position, the start position holding the valve pin in a gate closed position; a controller that instructs the valve system to move from the start position to the one or more intermediate drive rate positions and to remain in the one or more intermediate drive rate positions for one or more corresponding predetermined amounts of time.

An acceleration distance for acceleration at a set acceleration rate, required for an ejection start position passing speed in an ejection start position, is obtained, and a position behind the ejection start position by the acceleration distance is set as an advance start position of an ejector. Thus, an ejector plate can start to move at an optimal speed.

A mold clamping apparatus according to the present invention includes: a fixed platen to which one mold of a pair of molds is to be mounted; a movable platen which is disposed opposite the fixed platen and to which the other mold is to be mounted; a pressure-receiving platen connected to the fixed platen via tie bars; a mold opening/closing mechanism including a toggle link mechanism for opening/closing and clamping the molds by moving the movable platen back and forth; a drive mechanism including a servo motor for driving the mold opening/closing mechanism; and a control device for controlling the servo motor, wherein the control device includes an acceleration/deceleration adjustment section capable of adjusting an acceleration time, a deceleration time and a target speed of the servo motor during a mold clamping operation.

An apparatus for controlling the rate of flow of a fluid mold material comprising: a manifold, an actuator interconnected to a valve pin, a position sensor that senses position of the valve pin, a controller that controls movement of the actuator according to instructions that instruct the actuator to drive the valve pin upstream at one or more selected intermediate velocities in response to receipt by the controller of a signal from the position sensor that the valve pin is disposed in the one or more intermediate upstream gate open positions.

An apparatus for controlling the rate of flow of a fluid mold material comprising: a manifold, an actuator interconnected to a valve pin, a position sensor that senses position of the valve pin, a controller that controls movement of the actuator according to instructions that instruct the actuator to drive the valve pin upstream at one or more selected intermediate velocities in response to receipt by the controller of a signal from the position sensor that the valve pin is disposed in the one or more intermediate upstream gate open positions.

An apparatus for controlling the rate of flow of mold material to a mold cavity, the apparatus comprising: an injection molding machine and a manifold; an actuator interconnected to a valve pin having a tip end; a valve system in fluid communication with the actuator to drive the actuator at one or more rates of travel, the valve system having a start position, one or more intermediate drive rate positions and a high drive rate position, the start position holding the valve pin in a gate closed position; a controller that instructs the valve system to move from the start position to the one or more intermediate drive rate positions and to remain in the one or more intermediate drive rate positions for one or more corresponding predetermined amounts of time.