In a molding die, movable die elements are respectively received in die element receiving holes formed in a frame plate. An end surface of the frame plate, which faces a cavity at a location that is other than locations of the die element receiving holes, forms a frame portion compression surface. An end surface of each movable die element, which faces the cavity, forms a split compression surface. Die element drive devices respectively drive the split compression surfaces of the movable die elements. A whole compression plate commonly supports an opposite end part of the frame plate and opposite end parts of the movable die elements, which are opposite from the cavity. When the whole compression plate is moved forward, the whole compression plate integrally drives the frame plate and the movable die elements forward. A whole drive device drives the whole compression plate.

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 method for adjusting the closing force of a mold of a plastics processing machine. In order to work with an optimized closing force, the method comprises the steps of: a) in a first production cycle: Closing the mold with a nominal initial closing force and recording the mold deformation caused thereby and calculating the deformation work introduced by the mold deformation; b) in a subsequent further production cycle: Closing the mold with a reduced closing force and recording the resulting mold deformation and calculating the deformation work introduced by the mold deformation; c) Recording the determined deformation work versus the closing force, carrying out a linear extrapolation of the course of the deformation work versus the closing force and determining a reduced closing force which is at a predetermined percentage value of one of the previously determined deformation work; d) Carrying out the subsequent further production cycle with the determined reduced closing force.

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 method of monitoring and controlling a molding clamping apparatus in an injection molding or other molding process is disclosed. The method includes creating a target strain profile, receiving a deviation limit, receiving a change in strain relating to a mold while it is closing from a first strain gauge, identifying a deviation from a target strain profile based on the output from the first strain gauge, determining that the deviation exceeds the deviation limit, and adjusting the rate or force of clamp movement. The target strain profile may have a first portion relating to a clamp closing process, a second portion relating to a filling process, and a third portion relating to a clamp opening process. The first portion relating to the clamp closing process may include an intermediate portion relating to a coining process having an intermediate clamp force setpoint.

An injection molding includes: a clamping mechanism (conversion mechanism and toggle mechanism) for moving a fixed platen that retains a fixed die toward a fixed platen that retains a fixed die to bring the fixed die and the movable die into contract, and generating a clamping force therebetween; a drive source (mold opening/closing motor) for driving the clamping mechanism; a clamping force detection unit for detecting the clamping force; an elongation value detection unit for detecting an elongation value indicating the amount of elongation of a tie bar that extends as the clamping force is generated; and an abnormality determination unit for determining an abnormality in the injection molding machine on the basis of the ratio of the elongation value and the clamping force.

A technique for providing assistance in setting the time to increase the clamping force is provided. A control device of an injection molding machine includes a clamping control part and a monitoring part. The clamping control part is configured to change, in a filling step of filling the inside of a mold device with a molding material during clamping, a set value of clamping force from a first set value to a second set value that is larger than the first set value, at a predetermined pressurizing timing in the middle of the filling step. The monitoring part is configured to monitor changes in the actual value of the clamping force due to changes in the set value of the clamping force.

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.

An injection molding machine is provided that includes a clamping force sensor that detects a clamping force of a mold, and a clamping force monitoring unit that monitors a detected value of the clamping force sensor and calculates a first mold open distance and/or a second mold open distance. The first mold open distance is calculated based on the difference between the maximum value of the detected values obtained during an injection process and a pressure holding process and the detected value obtained at the start of the injection process. The second mold open distance that is calculated based on the difference between the detected value obtained at the end of the pressure holding process and the detected value obtained at the start of the injection process.

A monitoring apparatus for molds includes a control unit connectable to a first and second sensor associable with the mold and configured for emitting respective signals representative of a deformation parameter and temperature parameter of the mold. The control unit, in order to define an alert condition, is configured for: defining a value of a threshold parameter as a function of the temperature of the mold and comparing such value of the deformation parameter with a value of a threshold parameter defined as a function of the temperature of the mold; or normalizing, at a reference temperature, the value of the deformation parameter determined at the temperature of the mold and comparing a value of a threshold parameter, defined at the reference temperature, with the value of the normalized deformation parameter at the same reference temperature. Also forming the object of the present invention is a monitoring method and a data medium.