Injection molding machine for machining of plastic products

Abstract

The invention relates to the technical field of injection molding equipment, and discloses an injection molding machine for machining of plastic products. The injection molding machine comprises a stock bin, a screw, a screw head, a thrust ring and a check ring. The thrust ring and the screw head are both in threaded connection with the screw, and the check ring is located between the thrust ringand the screw head. According to the injection molding machine for machining of the plastic products, in a low-temperature state, a spring piece can deform into a conical threaded groove with which the screw head is coated, the washing effect of a washing medium on the inner walls of the screw head and the stock bin is enhanced, impurities and scorching melt on the inner walls can be scraped off,then, under the effect of the elasticity of the spring piece, the check ring can move to the thrust ring by itself, the flow path of the melt is reduced, pre-check is achieved, at the moment when a hydraulic device is started, the contact pressure of the thrust ring and the check ring is increased, complete check can be achieved, the elasticity of the spring piece can compensate for abrasion generated by relative rotation between the screw head and the check ring, and the service life of the check ring can be effectively prolonged.

Description

technical field [0001] The invention relates to the technical field of injection molding equipment, in particular to an injection molding machine for processing plastic products. Background technique [0002] The injection molding machine consists of injection molding screw, check ring, thrust ring, screw head and hydraulic device. The screw rotates to inject the molten plastic in the silo into the front-end metering chamber of the injection molding machine, and then the hydraulic device pushes the screw horizontally to squeeze out the molten plastic. out, injected into the mold, cooled and formed. [0003] The screw heads of injection molding machines are generally tapered, which can effectively reduce the injection resistance and reduce the retention of molten material in front of the screw. However, since the plastic will decompose when heated, the inner surface of the metering chamber and the screw head will stick and burn. With the accumulation of scorched plastic, on ...

AI Technical Summary

Problems solved by technology

[0003] The screw heads of injection molding machines are generally tapered, which can effectively reduce the injection resistance and reduce the retention of molten material in front of the screw. However, since the plastic will decompose when heated, the inner surface of the metering chamber and the screw head will stick and burn. With the accumulation of scorched plastic, on the one hand, it will reduce the injection molding precision and reduce the quality of injection molding. On the other hand, the scorched molten material adhered to the wall of the metering chamber, as impurities, is easy to get stuck when the non-return ring moves. In the gap between the non-return ring and the metering chamber, the contact surface will be poorly contacted, which will increase the reverse flow of the molten material. What is more serious, if the burnt molten material accumulates too much, it will cause the extruder to malfunction.

[0004] There is at least one friction between the non-return ring and the screw head and between the non-return ring and the inner wall of the silo. The friction between the non-return ring and the screw head will increase the sliding distance of the non-return ring, so that the push ring seals the inner space of the non-return ring The required time increases, the return flow of molten material increases, and the measurement accuracy is reduced. Similarly, the increase in the gap between the check ring and the inner wall of the silo will cause the molten material to flow backward, reducing injection molding efficiency and measurement accuracy.

Images