A time Gt from the start of an injection step until a mold clamping operation is complete is compared with an operation time Ct for a mold clamping step. For Gt<Ct, the injection step is started when a time Dt equal to a difference between Gt and Ct elapses. On the other hand, for Gt≧Ct, after the start of the injection step, a movable platen is stopped at a mold touch position until the time Dt elapses. When the time Dt elapses, the mold clamping step is started.

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.

The present invention provides a molding machine that can easily detect viscosity of resin in a cylinder without advance preparations. An injection molding machine (10) includes an ultrasonic viscosity sensor (20), and the ultrasonic viscosity sensor (20) includes an ultrasonic vibration portion in contact with resin filled in a cylinder (12).

The invention relates to a system for controlling a shutter (110) slidably arranged in a plastic material injection nozzle (11), comprising a rotary electric motor (M) and a mechanism adapted to couple said motor (M) to the shutter to slidably drive it between a closing position of the nozzle and a maximum opening position of the nozzle, characterised in that said mechanism comprises: an eccentric (21) integral with an output shaft (20) of the motor so as to be rotationally driven by said output shaft, comprising a crank pin (22) parallel to the output shaft but non-coaxial with said shaft (20), a slide (23) adapted to be made integral with one end of the shutter (110), and a connecting rod (25), a first end of which is articulated on the crank pin (22) of the eccentric (21) and a second end is articulated on an axis (25b) of the slide (23) such that the rotation of the eccentric causes sliding of the oscillating shutter between the closing position and the maximum opening position.

A system, method and apparatus for controlling an injection unit to transfer a material to a mold cavity includes a first actuator and a second actuator, and a controller that is operatively connected to the first actuator and the second actuator. The first and second actuators are coupled to a ram of the injection unit. The first actuator rotates the ram within the barrel, and the second actuator translates the ram within the barrel. During a material fill stage of an injection cycle, the controller controls the first actuator to rotate the ram within the barrel. The controller also controls the second actuator to translate the ram within the barrel, and controls the second actuator to retract the ram away from a nozzle of the injection unit while exerting a compression force on the ram towards the nozzle.

Apparatus and method for performing an injection molding cycle using the apparatus where the apparatus comprises: a manifold, a pneumatic actuator driven by a pneumatic valve assembly, the actuator driving a valve pin between a gate closed position and a maximum injection fluid flow position, the pneumatic valve assembly having a spool supported within a cylinder driven by a drive device that is supported solely by and translates together with the spool, a controller that instructs the pneumatic valve assembly to cause the actuator to drive the valve pin either upstream or downstream to selected positions or at selected velocities during the course of a single injection cycle based on a feedback signal indicative of position of the pin or actuator or pressure of an injection fluid material.

A substantially constant pressure injection molding method and machine that forms molded parts by injecting molten thermoplastic material into a mold cavity at a substantially constant pressure. As a result, the mold cavity is filled with molten thermoplastic material by advancing a continuous flow front of thermoplastic material from a gate to an end of the mold cavity.

A method for injection molding of plastic material by means of at least one injector whose pin valve can be displaced between a fully closed position and a maximum open position in a controlled fashion according to a position and speed of the pin valve. During displacement of the pin valve from the fully closed position to the maximum open position, and/or vice versa, the pin valve is stopped in intermediate positions and the displacement speed thereof is uniform and constant. An initial opening step at maximum speed and one or more steps of inversion of the motion of the pin valve can be provided for.

A method of detecting and compensating for a non-operational mold cavity in an injection molding apparatus having a plurality of mold cavities and an injection molding screw or ram includes injecting, via the injection molding screw or ram, a molten thermoplastic material into the plurality of mold cavities. The method includes measuring a first process parameter of the injection molding apparatus at a pre-determined time during or after the injecting. The method also includes determining, based on the first process parameter, whether one or more mold cavities of the plurality of mold cavities are non-operational. Then, when it is determined that one or more mold cavities are non-operational, the method includes automatically adjusting the first process parameter or a second process parameter of the injection molding apparatus.

A phase adjusting device includes: a torque acquisition unit acquiring a torque; a position acquisition unit acquiring the rotational position of the first motor; a first motor control unit rotating the first motor in a first rotational direction until the torque exceeds a threshold, and then in a second rotational direction until the torque exceeds the threshold again; a storage control unit storing, in a storage unit, a first rotational position when the first motor is rotated in the first rotational direction and the torque exceeds the threshold and a second rotational position when the first motor is rotated in the second rotational direction and the torque exceeds the threshold again; a phase position calculator calculating a third rotational position, based on the first and second rotational positions; and a second motor control unit rotating the first motor to the third rotational position.