A predetermined mold gap is provided beforehand between a movable mold and a stationary mold of a mold by a mold clamping device. A mold clamping pressure is set to zero, and a predetermined back pressure is set for the movable mold. Subsequently, the injection device is caused to start injection of the molten resin into the mold for which the mold gap, the mold clamping pressure, and the back pressure have been set. When a predetermined injection end condition set beforehand is satisfied as a result of progress of an injection filling process, a filling end process of ending the injection filling process is performed.

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 brake control method for an injection molding machine includes the steps of obtaining mold clamping force information indicating the mold clamping force of a mold opening/closing mechanism and determining whether or not the mold clamping force of the mold opening/closing mechanism exceeds a predetermined value, based on the mold clamping force information. When the mold clamping force of the mold opening/closing mechanism does not exceed the predetermined value and when a servo amplifier cuts off the supply of power to a servomotor that drives the mold opening/closing mechanism, a brake mechanism for applying braking force to the mold opening/closing mechanism is actuated. On the other hand, when the mold clamping force of the mold opening/closing mechanism exceeds the predetermined value, the brake mechanism will not be actuated.

A display unit displays a display screen including information on injection molding, and the display screen displays a setting screen portion that displays setting contents of the injection molding and a power screen portion that displays information on power consumption of the injection molding based on the setting contents together.

A molding injection pressure and a molding clamping force are determined in advance to obtain a parting opening amount, which is a predetermined gap, between a movable mold and a fixed mold of a mold during injection filling. The molding injection pressure and the molding clamping force are determined to obtain a molding injection pressure capable of molding a good product and a mold clamping force capable of molding a good product, respectively, thereby setting a specific molding condition, setting a fast injection speed from the start of injection, which is higher than the injection speed set by the specific molding condition, and setting a fast injection section for continuing the fast injection speed as a fast injection condition, mold-clamping the mold by the molding clamping force during molding, and setting the molding injection pressure to a limit pressure, injecting and filling resin into a mold by the fast injection condition from the start of injection, and injecting and filling resin by the specific molding condition when the fast injection section ends.

Mold clamping conditions, including a predetermined mold gap, a predetermined mold clamping force, a predetermined back pressure for a movable mold, a predetermined mold closing pressure, and a predetermined mold closing pressure adjustment condition associated with the compression state of a molding material, are set beforehand. At the time of molding, an injection filling process for causing the injection device to inject and fill the molding material into a mold of a mold clamping device for which the mold clamping conditions have been set is performed, and, after completion of the injection filling process, a compression process is performed on the basis of the mold clamping conditions including the mold closing pressure adjustment condition.

In an injection molding system, a holding force changing means reduces a holding force to a predetermined level or less if a predetermined or higher load is detected by an external load detection means after a molded article is transported to a work area of an operator by a molded article transport device. Thus, the operator can easily take out and inspect the molded article.

An injection molding apparatus includes a support that supports a molding die including an upper die and a lower die, and an injection unit that injects a molding material toward a cavity defined by the upper die and the lower die. In the state in which the molding die is supported by the support, the injection unit, the upper die, and the lower die are arranged sequentially from above in the vertical direction. The injection unit includes a rotating flat screw having a groove forming surface in which a groove is formed, a barrel having a flat screw facing surface facing the groove forming surface and having a communication hole into which the molding material flows, and a heater that heats a material supplied to the space between the groove forming surface and the flat screw facing surface, plasticizes at least part of the material through the rotation of the flat screw and the heat produced by the heater to produce the molding material, and delivers the molding material to the communication hole.

An injection molding machine has a clamp that generates electromagnetic force and that secures a moving plate or a fixed plate using attractive force that is produced by the electromagnetic force; and a controller that controls separation force that acts on the moving plate or the fixed plate such that the separation force is less than the attractive force.

An injection molding machine has a clamp that generates electromagnetic force and that secures a moving plate or a fixed plate using attractive force that is produced by the electromagnetic force; a pressure sensor that is provided in the clamp, wherein the pressure sensor measures contact pressure that acts between the moving plate or the fixed plate and the clamp; and a controller for performing a measure to prevent detachment of the moving plate or the fixed plate based on the contact pressure.