Mold opening and closing control of injection molding control

Mold opening control:
When the molten plastic is injected into the mold cavity and the cooling is completed, the mold opening action is followed and the product is taken out. The mold opening process is also divided into three stages. The first stage is to open the mold slowly to prevent the parts from tearing in the mold cavity.
The second stage is rapid mold opening to shorten the mold opening time. The third stage is to open the mold slowly to reduce the impact and vibration caused by the mold inertia.
Mold closing control:
Mold closing is to close the mold tightly with a huge mechanical thrust to resist the huge opening force of the mold caused by the high-pressure injection and filling of molten plastic during the injection molding process.
Close the safety door, all travel switches give signals, and the mold closing action starts immediately. First of all, the movable template is started at a slow speed. After a short distance, the control rod pressing block that originally pressed the slow switch is separated, and the movable plate rotates to move forward quickly. When moving forward to the end of mold closing, the pressing rod at the other end of the control rod presses the slow switch again, and then the movable plate turns to slow speed and advances at low pressure.
In the process of low pressure mold closing, if there is no obstacle between the molds, the mold can be closed smoothly until the high pressure switch is pressed. The high pressure switch is used to straighten the hinge to complete the mold closing action. This distance is very short, generally only 0.3~1.0mm. The closing limit switch is touched immediately after the high voltage is turned on. At this time, the action stops and the closing process ends.
The clamping structure of the injection molding machine includes full hydraulic type and mechanical connecting rod type. No matter what kind of structure, the clamping force is finally implemented by the complete straightening of the connecting rod. The straightening process of the connecting rod is the process of spreading the movable plate and the tail plate, and also the process of stretching the four connecting rods under the force.
The size of the clamping force can be known from the highest value of the oil pressure gauge rising at the moment of clamping. If the clamping force is large, the highest value of the oil pressure gauge will be high, and vice versa. Smaller injection molding machines do not have a clamping oil pressure gauge. At this time, it is necessary to judge whether the mold is really tight according to the straightness of the connecting rod.
If the connecting rod of an injection molding machine is easily straightened during mold closing, or "almost" fails to straighten, or one of several connecting rods is not fully straightened, mold expansion will occur during injection molding, and the parts will have flash or other defects.