A controller of an injection molding machine controls mold clamping of a fixed mold and a movable mold. The controller includes a servomotor drive control unit for limiting increase in driving current during driving of a mold clamping servomotor, and a moving state acquisition unit that acquires a detection signal of an encoder. The controller further includes an abnormality determination processing unit for determining that a clamping force sensor is abnormal when recognizing stoppage of movement of the movable mold during mold clamping, based on the acquired detection signal of the encoder.

A molding injection pressure Pi with which a parting opening Lm is formed between a movable mold 2m and a fixed mold 2c during injection-filling and which allows formation of a good molded article is obtained and set in advance. A molding clamping force Pc that allows formation of a good molded article is obtained and set in advance. During production, a mold clamping device Mc is clamped with the molding clamping force Pc, and an injection device Mi to apply the molding injection pressure Pi as a limit pressure Ps is driven to injection-fill a mold 2 with resin R. A parting opening detector 3 that detects the parting opening Lm is provided. During production, reset control is executed to reset the parting opening detector 3 to zero if reset timing tr set in advance has come at least on condition that given preparation for injection is completed after clamping. The reset timing is set in a range covering a given period Zs before injection start time and the given period Zs after the injection start time.

A distortion sensor is provided on each of a plurality of tie bars and the extension amount of each tie bar is detected by the distortion sensor thereof, whereby a mold clamping force actually applied to a mold is measured. This measurement specifies the part of the mold that first opens and obtains a minimum mold clamping force that does not open the mold in that part. The minimum mold clamping force thus obtained is the minimum mold clamping force that does not open the mold without being influenced by factors such as the shape and the arrangement of a cavity in the mold and the mold clamping force balance of a mold clamping part of an injection molding machine.

An injection molding machine includes: a clamping device having a fixed mold and a movable mold, configuring a mold, and a clamping force sensor to detect a clamping force of the movable mold to the fixed mold; an injection device having an injection nozzle and a screw to fill the mold with a molten resin via the injection nozzle; and a control device, wherein the control device monitors a variation of the clamping force from the clamping force sensor, causes a slow speed forward movement time at a timing of VP switching to be increased if the variation exceeds a predetermined upper limit, and causes the slow speed forward movement time at the timing of VP switching to be reduced if the variation falls below a predetermined lower limit.

An operation abnormality detection method for detecting an operation abnormality in a molding device having a movable part includes: acquiring a prescribed measured value relating to operation of the movable part and calculating, as statistical information, an average value of prescribed information values based on the prescribed measured values: calculating a first threshold and a second threshold; acquiring a current measured value and comparing a current information value based on the current measured value with the greater of the first threshold and the second threshold; and issuing a warning if the current information value at least exceeds the greater of the first threshold and the second threshold.

An injection molding machine includes a plasticizing unit having a plasticizing cylinder and a material-conveying device that is movable in the plasticizing cylinder and powered by a material-conveying drive, a material-conveying drive control, which is coupled with the material-conveying drive and is designed to control operating parameters of the material-conveying drive, a closing unit having an injection molding tool that is connected with an outlet nozzle of the plasticizing cylinder, as well as a closing unit control, which is coupled with a closing unit drive of the closing unit and is designed to control operating parameters of the closing unit drive. The injection molding machine further includes one or more dieletric or acoustic sensors which are disposed in the cavity of the injection molding tool or close to the cavity of the injection molding tool and are designed to determine the dielectric polarizability, mobility of free load carriers and/or acoustic material responses of a molding material in the cavity of the injection molding tool. A sensor control is coupled with the dielectric or acoustic sensor(s) and is designed to ascertain a time-dependent degree of crystallization and a time-dependent median temperature of the molding material in the cavity of the injection molding tool from the dielectric polarizability, mobility of free load carriers and/or acoustic material responses determined by the dielectric sensor(s) and, depending on the ascertained degree of crystallization and the ascertained median temperature, to actuate the material-conveying drive control and/or the closing unit control to adjust the operating parameters of the material-conveying drive and/or of the closing unit drive.

A controller is configured to obtain a torque waveform of a servo motor while an ejector pin is operating, compare the torque waveform with a reference waveform obtained in advance, and determine that an ejector is abnormal when a difference between the torque waveform and the reference waveform exceeds a threshold value.

A manufacturing apparatus and method for a resin container. The apparatus includes at least: a heating unit configured to heat a preform; a blow molding part configured to mold a plurality of the preforms into a container; and a conveyance member configured to convey the plurality of preforms that has been heated to the blow molding part. The conveyance member includes: a plurality of holding arms each configured to hold one of the plurality of preforms; a connecting member configured to connect together the plurality of holding arms at equal intervals; and a pitch changing mechanism configured to change a pitch between the plurality of holding arms, and the pitch changing mechanism includes a stopper mechanism configured to position the plurality of holding arms at a predetermined wide pitch when an interval of the holding arms is changed from a narrow pitch to the predetermined wide pitch.

An injection molding apparatus includes an injection unit, a mold clamping unit, and a controller. The mold clamping unit includes a toggle fixing plate, a fixed mold attachment portion, a movable mold attachment portion movable in a mold clamping direction, a motor, a ball screw configured rotated by the motor, a crosshead configured to move between the toggle fixing plate and the movable mold attachment portion due to rotation of the ball screw, and a toggle section coupled to the toggle fixing plate. The movable mold attachment portion and the crosshead are configured to move the movable mold attachment portion. A position detector is configured to detect a position of the crosshead. The controller controls the position of the crosshead based on a detection result of the position detector to make the toggle section operate to perform the mold clamping of the fixed mold and the movable mold.

A mold clamping device includes two mold platens; a ball screw mechanism connecting the mold platens to each other, the ball screw mechanism being provided with an axial force detector configured to detect an axial force acting on the ball screw mechanism; a servo motor provided on the ball screw mechanism and configured to drive the ball screw mechanism; and a control device configured to: monitor the axial force detected by the axial force detector during injection; and based on detecting an axial force increase, the axial force increase being an increase in the axial force, perform a mold clamping force increase control including driving the servo motor to increase a mold clamping force for tightening the ball screw mechanism.