Pressure-maintaining hot runner nozzle

Abstract

The invention discloses a pressure-maintaining hot runner nozzle. The pressure-maintaining hot runner nozzle comprises a channel cylinder and a nozzle. The center of the channel cylinder is provided with an injection channel and a liquid storage cavity. The nozzle comprises a spray-head part and a sleeve pipe. The sleeve pipe is connected to the inner wall of the liquid storage cavity by screw threads. The spray-head part is provided with an injection port. The center of the sleeve pipe is provided with a liquid communication chamber. The liquid storage cavity is provided with a plunger. A forth-step column can go deep into the injection channel. A second-step column is sleeved by a spring. One end of the spring can press against the sleeve pipe and the other end can press against the surface of a third-step column. The pressure-maintaining hot runner nozzle has the advantages that the plunger moves backwards under the action of the spring and the forth-step column blocks the injection channel thereby blocking a flowing channel of plastic melt so that plastic pressure-maintaining effects are superior to those of the existing injection port cooling solidification.

Description

technical field [0001] The invention relates to a hot runner nozzle, in particular to a hot runner nozzle with a pressure maintaining function. Background technique [0002] The hot nozzle is an important part of the hot runner system. It is commonly used in the injection molding industry. There is a heating system around the hot nozzle, so that the plastic melt in the cavity is always in a molten state, so that the liquid can be released quickly in the next injection. [0003] During standby, the residual plastic melt in the channel at the center of the nozzle is always in a molten state, but the melt in the injection port of the nozzle is cooled and solidified during standby, thereby playing the role of sealing and pressure keeping, but its sealing and The pressure holding performance is limited. If the pressure is slightly higher, the plastic melt will rush out of the injection port. [0004] In this way, it is required to reduce the pressure when holding the pressure, b...

AI Technical Summary

Problems solved by technology

[0003] During standby, the residual plastic melt in the channel at the center of the nozzle is always in a molten state, but the melt in the injection port of the nozzle is cooled and solidified during standby, thereby playing the role of sealing and pressure keeping, but its sealing and The pressure holding performance is limited. If the pressure is slightly higher, the plastic melt will rush out of the injection port.

[0004] In this way, it is required to reduce the pressure when maintaining the pressure, but the smaller the pressure may cause the density of the residual plastic melt to become smaller, after molding, the local mechanical properties of the parts will deteriorate, which is an unfavorable factor

Images