Needle valve meson for buffering pressure to protect mold core sprue

Abstract

The utility model provides a needle valve meson for buffering pressure to protect a mold core sprue. The needle valve meson comprises a hot runner needle valve main body, a valve needle axially extending, a valve needle sleeve sleeved outside the valve needle, a valve sleeve pressing cap for extruding and fixing the valve needle sleeve, an air cylinder assembly, an injection nozzle, a splitter plate, a hot nozzle and an electromagnetic valve assembly, the air cylinder assembly comprises an air cylinder cover, an air cylinder body, a piston located on the inner side of the air cylinder body, a first air channel, a second air channel, a first Glyd ring and a second Glyd ring, wherein the first air channel and the second air channel are communicated with the air cylinder body through pipelines, and the first Glyd ring and the second Glyd ring are located on the outer side of the air cylinder body. The needle valve meson, the pressure detector, the small pressure relief piston and the limiting screw are used for achieving the pressure relief function. According to the needle valve meson with the pressure relief function, under the condition that the air inlet pressure is simply adjusted and the normal needle sealing pressure is guaranteed, the valve needle buffers and protects a mold core sprue, and the service life of a mold is effectively prolonged.

Description

[Technical Field]

[0001] This utility model relates to the field of injection mold technology, specifically to a needle valve type hot runner system structure with pressure buffer function, which is particularly suitable for gate protection of high-precision injection molding molds. [Background Technology]

[0002] In existing needle valve hot runner systems, the valve pin exerts a continuous impact on the mold core gate during high-pressure injection molding, which can easily lead to the following problems:

[0003] A. Stress concentration in the gate area;

[0004] B. The coating on the mold core surface is prone to peeling off;

[0005] C. The diameter of the gate gradually increases due to wear;

[0006] D. The average lifespan of the mold is only 150,000-200,000 cycles;

[0007] To address the above problems, existing solutions have at least the following limitations:

[0008] 1. Simply increasing the hardness of the material leads to increased costs;

[0009] 2. Traditional buffer structures affect injection molding accuracy;

[0010] 3. Unable to simultaneously address pressure relief and sealing requirements;

[0011] How to effectively solve and reduce the impact on the mold core gate when the valve needle closes is a key issue that those skilled in the art need to consider. [Utility Model Content]

[0012] The problem with the prior art that this application addresses is:

[0013] A. Stress concentration in the gate area;

[0014] B. The coating on the mold core surface is prone to peeling off;

[0015] C. The diameter of the gate gradually increases due to wear;

[0016] D. The average lifespan of the mold is only 150,000-200,000 cycles.

[0017] The solution to the technical problem of this utility model is:

[0018] A needle valve is provided for buffering pressure and protecting the mold core gate, comprising a hot runner needle valve main body, an axially extending valve needle, a valve needle sleeve sleeved outside the valve needle, a valve sleeve cap for pressing and fixing the valve needle sleeve, a cylinder assembly, an injection nozzle, a manifold, a hot nozzle, and a solenoid valve assembly; the cylinder assembly includes a cylinder head, a cylinder body, a piston located inside the cylinder body, a first air passage and a second air passage connected to the cylinder body via pipes, and a first and second Gladius rings located outside the cylinder body; it also includes... The device includes a needle valve, a pressure detector, a pressure relief piston, and a limiting screw to achieve the pressure relief function. The limiting screw has an exhaust groove at its bottom to allow sealed compressed air to escape through the gap. When the piston moves downwards to close, the air sealing the inside of the needle valve is compressed. The compressed gas pushes the pressure relief piston up through the exhaust port. Due to the exhaust groove, the compressed air escapes through the gap. When the piston retracts, the pressure inside the needle valve is relieved, the pressure relief piston falls back, and external gas enters through the bottom of the pressure relief piston.

[0019] Preferably, the pressure detector is used to detect the actual pressure of the cavity, and then adjust the actual air intake pressure to ensure that the piston drives the valve needle with sufficient thrust. At the same time, the piston buffer protects the mold core gate located at one end of the hot runner needle valve main body to reduce the impact of the valve needle.

[0020] Preferably, the second air path drives the piston valve needle to open, and after the injection action is completed, the solenoid valve assembly reverses the gas to drive the piston so that the valve needle head closes with the mold core gate.

[0021] Preferably, the outer surface of the valve needle is plated with a hard chrome structural layer, and the outer surface of the hard chrome structural layer is coated with a heat-resistant and non-stick layer; the outer surface of the hard chrome structural layer is covered with nanopores to form a nanopore surface, and the heat-resistant and non-stick layer is tightly bonded to the nanopore surface of the hard chrome structural layer by an integral injection molding method to form an integral structure.

[0022] Preferably, the hot runner needle valve body is provided with a sealing section, a pressure relief section and a buffer section in sequence; the pressure relief section has a pressure relief groove on its surface; the groove depth ranges from 0.1 to 0.3 mm; the buffer section is fitted with an elastic buffer assembly; the elastic buffer assembly includes a shape memory alloy washer and a silicon copper alloy sleeve; the helix angle of the pressure relief groove is 25-35°, and the groove width to groove depth ratio is 2:1 to 5:1; the elastic buffer assembly is provided with a temperature compensation structure.

[0023] Preferably, a heating coil is provided on the outer side of the injection nozzle.

[0024] The technical effects achieved by this application in solving the technical problem are as follows:

[0025] Compared with the prior art, the needle valve mediator of the buffer pressure protection mold core gate of this utility model is provided by simultaneously setting a hot runner needle valve main body, an axially extended valve needle 3, a valve needle sleeve 9 sleeved on the outside of the valve needle, a valve sleeve cap 8 for squeezing and fixing the valve needle sleeve 9, a cylinder assembly, an injection nozzle, a manifold 10, a hot nozzle 11, and a solenoid valve assembly; the cylinder assembly includes a cylinder head 1, a cylinder body, a piston 2 located inside the cylinder body, a first air passage 15 and a second air passage 16 connected to the cylinder body through a pipe, and a first Gladius ring 4 and a second Gladius ring 5 located outside the cylinder body; it also includes a needle valve mediator 6 for realizing the pressure relief function, a pressure detector 7, and a pressure relief valve. The valve 13 and the limiting screw 14 are provided; the bottom of the limiting screw 14 is provided with an exhaust groove for discharging the sealed compressed air from the gap; when the piston 2 moves downward to close, the air sealing the inside of the needle valve medium 6 is compressed, and the compressed gas pushes the pressure relief small piston 13 up through the exhaust port. Due to the setting of the exhaust groove, the compressed air is discharged from the gap. When the piston 2 retracts, the pressure inside the needle valve medium 6 is relieved, the pressure relief small piston 13 falls back, and the external gas enters through the bottom of the pressure relief small piston 13. In practical applications, a needle valve medium with pressure relief function is used. By simply adjusting the air inlet pressure and ensuring the normal sealing needle pressure, the valve needle buffer protects the mold core gate, effectively extending the service life of the mold. [Image Description]

[0026] Figure 1 This is a schematic diagram of the overall three-dimensional structure of the needle valve medium for the mold core gate of the present invention, which is a buffer pressure protection device.

[0027] Figure 2 This is a schematic diagram of the overall cross-sectional structure of the needle valve medium for the mold core gate of the present invention, which is a buffer pressure protection device. [Detailed Implementation]

[0028] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments.

[0029] It should be understood that the specific embodiments described herein are merely for explaining the present invention and are not intended to limit the present invention.

[0030] Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0031] It should be noted that when a component is said to be "fixed" to another component, it can be directly on the other component or it can be in a middle component. When a component is said to be "connected" to another component, it can be directly connected to the other component or it may be in a middle component.

[0032] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0033] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0034] The following detailed description, in conjunction with the accompanying drawings, outlines some embodiments of the present invention. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0035] Please see Figure 1 and Figure 2 This utility model discloses a needle valve mediator 20 for buffering pressure protection of mold core gate, comprising a hot runner needle valve main body, an axially extending valve needle 3, a valve needle sleeve 9 sleeved outside the valve needle, a valve sleeve cap 8 for pressing and fixing the valve needle sleeve 9, a cylinder assembly, an injection nozzle, a manifold 10, a hot nozzle 11, and a solenoid valve assembly; the cylinder assembly includes a cylinder head 1, a cylinder body, a piston 2 located inside the cylinder body, a first air passage 15 and a second air passage 16 connected to the cylinder body via pipes, and a first glyph 4 and a second glyph 5 located outside the cylinder body; and also... It includes a needle valve chamber 6 for realizing the pressure relief function, a pressure detector 7, a pressure relief small piston 13, and a limiting screw 14; the bottom of the limiting screw 14 is provided with an exhaust groove for discharging the sealed compressed air from the gap; when the piston 2 moves downward to close, the air sealing the inside of the needle valve chamber 6 is compressed, and the compressed gas pushes the pressure relief small piston 13 up through the exhaust port. Due to the exhaust groove, the compressed air is discharged from the gap. When the piston 2 retracts, the internal pressure of the needle valve chamber 6 is relieved, the pressure relief small piston 13 falls back, and external gas enters through the bottom of the pressure relief small piston 13.

[0036] This application simultaneously comprises a hot runner needle valve main body, an axially extending valve needle 3, a valve needle sleeve 9 fitted outside the valve needle, a valve sleeve cap 8 for pressing and fixing the valve needle sleeve 9, a cylinder assembly, an injection nozzle, a manifold 10, a hot nozzle 11, and a solenoid valve assembly; the cylinder assembly includes a cylinder head 1, a cylinder body, a piston 2 located inside the cylinder body, a first air passage 15 and a second air passage 16 connected to the cylinder body via pipes, and a first Glyd ring 4 and a second Glyd ring 5 located outside the cylinder body; it also includes a needle valve mediator 6 for pressure relief, a pressure detector 7, a pressure relief small piston 13, and a limit screw 14; the... The bottom of the limiting screw 14 is provided with an exhaust groove to discharge the sealed compressed air from the gap. When the piston 2 moves downward to close, the air inside the sealing needle valve medium 6 is compressed. The compressed gas pushes up the pressure relief small piston 13 through the exhaust port. Due to the exhaust groove, the compressed air is discharged from the gap. When the piston 2 retracts, the internal pressure of the needle valve medium 6 is relieved, and the pressure relief small piston 13 falls back. External gas enters through the bottom of the pressure relief small piston 13. In practical applications, a needle valve medium with pressure relief function is used. By simply adjusting the air inlet pressure and ensuring the normal sealing needle pressure, the valve needle buffer protects the mold core gate, effectively extending the service life of the mold.

[0037] In some other embodiments, the pressure detector 7 is used to detect the actual pressure of the cavity, thereby adjusting the actual air intake pressure to ensure that the piston 2 drives the valve needle with sufficient thrust. At the same time, the piston 2 buffers and protects the mold core 12 gate located at one end of the hot runner needle valve main body from valve needle impact.

[0038] The second air passage 16 drives the piston 2 valve needle 3 to open. After the injection action is completed, the solenoid valve assembly reverses the gas to drive the piston 2 so that the head of the valve needle 3 closes the gate of the mold core 12.

[0039] The outer surface of the valve needle 3 is plated with a hard chrome structural layer, and the outer surface of the hard chrome structural layer is coated with a heat-resistant and non-stick layer; the outer surface of the hard chrome structural layer is covered with nanopores to form a nanopore surface, and the heat-resistant and non-stick layer is tightly bonded to the nanopore surface of the hard chrome structural layer by an integral injection molding method to form an integral structure.

[0040] The hot runner needle valve body is provided with a sealing section, a pressure relief section and a buffer section in sequence; the pressure relief section has a pressure relief groove on its surface; the groove depth ranges from 0.1 to 0.3 mm; the buffer section is fitted with an elastic buffer assembly; the elastic buffer assembly includes a shape memory alloy washer and a silicon copper alloy sleeve; the helix angle of the pressure relief groove is 25-35°, and the groove width to groove depth ratio is 2:1 to 5:1; the elastic buffer assembly is provided with a temperature compensation structure.

[0041] A heating coil is provided on the outside of the injection nozzle.

[0042] It is clear that this application does not limit the structural part in a unique way. In some other embodiments, corresponding improvements and modifications can be made according to different needs.

[0043] The following further elaborates on the main technical features involved in other embodiments of this application, in order to supplement the innovation of this application:

[0044] Core structure:

[0045] Stepped pressure relief valve needle;

[0046] The front working section (φ2.0-3.0mm) is made of cemented carbide;

[0047] A spiral pressure relief groove (groove depth 0.1-0.3mm) is installed in the middle section;

[0048] The rear buffer section is equipped with a flexible silicon-copper alloy sleeve;

[0049] Dynamic pressure balancing system:

[0050] The pressure relief channel is connected to the mold cooling water circuit;

[0051] Install pressure-sensitive shape memory alloy gaskets;

[0052] The conical seal mating angle is optimized to 58-62°;

[0053] Two-stage pressure relief mechanism:

[0054] Primary pressure relief: 20-30% of the melt pressure is diverted through the spiral groove;

[0055] Secondary buffer: The elastic sleeve absorbs the kinetic energy of mechanical impact;

[0056] Intelligent pressure regulation:

[0057] When the injection pressure is greater than 120MPa, the shape memory alloy gasket will deform automatically.

[0058] This creates a temporary pressure relief gap of 0.05-0.1 mm.

[0059] Technical effects:

[0060] Gate impact force is reduced by 40-60%;

[0061] The mold life has been increased to over 500,000 cycles.

[0062] Product weight fluctuations are controlled within ±0.15%;

[0063] Example 1: Application of automotive connector molds

[0064] Tungsten steel substrate with diamond-like carbon coating;

[0065] The pressure relief groove has a thread pitch of 1.2mm and a groove width of 0.25mm.

[0066] Combined with a nitrogen spring buffer system;

[0067] Example 2: Application of optical lens molds

[0068] Add a piezoelectric ceramic pressure sensor;

[0069] The pressure relief channel is linked to the mold temperature controller for control.

[0070] Buffer stroke: 0.8 ± 0.05 mm;

[0071] The hot runner needle valve system consists of a cylinder, injection nozzle, manifold, hot nozzle, valve needle, and solenoid valve assembly. The injection molding process involves the intake air driving the piston valve needle to open before injection, and after the injection is completed, the solenoid valve reverses the gas to drive the piston to close the valve needle head with the mold gate.

[0072] This patented design reduces the impact on the mold core gate when the valve needle closes. The new utility model features a pressure-relief needle valve mediator. When the piston descends to close, the air inside the sealed needle valve mediator is compressed, creating a buffering resistance when the valve needle reaches its bottom. A pressure-relief small piston structure is designed so that when the cylinder piston presses down, the compressed gas pushes the small piston up through the exhaust port. An exhaust groove is added to the bottom surface of the limit screw to allow the sealed compressed air to be discharged through an adjustable gap. When the cylinder piston retracts, the pressure inside the needle valve mediator is relieved, the small piston falls back, and outside gas can enter through the bottom of the small piston. A pressure detector is connected to measure the actual cavity pressure, and the actual air intake pressure is adjusted to ensure that the piston has sufficient thrust to drive the valve needle. At the same time, the piston buffers and protects the mold core gate from the impact of the valve needle. With this patented structure, by adjusting the air intake pressure and ensuring normal sealing pressure, the valve needle buffers and protects the mold core gate, effectively extending the mold's service life.

[0073] This utility model features a needle valve with a pressure relief function. By simply adjusting the air inlet pressure and ensuring normal sealing pressure, the valve needle buffers and protects the mold core gate, effectively extending the service life of the mold.

[0074] The technical effects achieved by this application in solving the technical problem are as follows:

[0075] Compared with the prior art, the needle valve mediator 1 of the buffer pressure protection mold core gate of this utility model is provided by simultaneously setting a hot runner needle valve main body, an axially extended valve needle 3, a valve needle sleeve 9 sleeved on the outside of the valve needle, a valve sleeve cap 8 for squeezing and fixing the valve needle sleeve 9, a cylinder assembly, an injection nozzle, a manifold 10, a hot nozzle 11, and a solenoid valve assembly; the cylinder assembly includes a cylinder head 1, a cylinder body, a piston 2 located inside the cylinder body, a first air passage 15 and a second air passage 16 connected to the cylinder body through a pipe, and a first Gladius ring 4 and a second Gladius ring 5 located outside the cylinder body; it also includes a needle valve mediator 6 for realizing the pressure relief function, a pressure detector 7, and a pressure relief valve. The valve 13 and the limiting screw 14 are provided; the bottom of the limiting screw 14 is provided with an exhaust groove for discharging the sealed compressed air from the gap; when the piston 2 moves downward to close, the air sealing the inside of the needle valve medium 6 is compressed, and the compressed gas pushes the pressure relief small piston 13 up through the exhaust port. Due to the setting of the exhaust groove, the compressed air is discharged from the gap. When the piston 2 retracts, the pressure inside the needle valve medium 6 is relieved, the pressure relief small piston 13 falls back, and the external gas enters through the bottom of the pressure relief small piston 13. In practical applications, a needle valve medium with pressure relief function is used. By simply adjusting the air inlet pressure and ensuring the normal sealing needle pressure, the valve needle buffer protects the mold core gate, effectively extending the service life of the mold.

[0076] The embodiments of this utility model described above do not constitute a limitation on the scope of protection of this utility model. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the scope of protection of the claims of this utility model.

Claims

1. A cushioning pressure protecting die core sprue pin valve meson characterized by: The hot runner needle valve main body, the axially extending valve needle, the valve needle sleeve, the valve sleeve pressure cap, the cylinder assembly, the injection nozzle, the flow distribution plate, the hot nozzle and the electromagnetic valve assembly; the cylinder assembly includes a cylinder head, a cylinder body, a piston inside the cylinder body, a first gas path and a second gas path connected to the cylinder body through a pipeline, and a first geyser ring and a second geyser ring outside the cylinder body; it also includes a needle valve meson for realizing pressure relief function, a pressure detector, a pressure relief small piston and a limit screw; the bottom of the limit screw is provided with an exhaust groove for discharging compressed air from the gap; when the piston descends to close, the air inside the needle valve meson is compressed, the compressed gas passes through the exhaust port to lift the pressure relief small piston, and due to the arrangement of the exhaust groove, the compressed air is discharged from the gap, when the piston is retracted, the needle valve meson is relieved, the pressure relief small piston falls back, and the external gas enters through the bottom of the pressure relief small piston.

2. A pressure relief pin valve die insert according to claim 1, wherein: The pressure detector is used to detect the actual pressure of the cavity, so as to adjust the actual inlet pressure and ensure that the piston drives the valve needle with sufficient thrust, and the piston buffer protects the mold core gate at one end of the hot runner needle valve main body from being impacted by the valve needle.

3. A pressure relief pin valve die insert according to claim 1, wherein: The second gas path drives the piston valve needle to open, and after the injection action is completed, the electromagnetic valve assembly changes the direction of the gas to drive the piston so that the valve needle head is closed with the mold core gate.

4. A pressure relief pin valve die insert according to claim 1, wherein: The outer surface of the valve needle is plated with a hard chrome structure layer, and the outer surface of the hard chrome structure layer is coated with a heat-resistant anti-sticking layer; the outer surface of the hard chrome structure layer is covered with nano-pores to form a nano-porous surface, and the heat-resistant anti-sticking layer is integrally formed with the nano-porous surface of the hard chrome structure layer by integral injection molding.

5. A pressure relief pin valve insert as claimed in any one of claims 1 to 4, wherein: The hot runner needle valve main body is provided with a sealing section, a pressure relief section and a buffer section in sequence; the surface of the pressure relief section is provided with a pressure relief groove; the groove depth of the pressure relief groove ranges from 0.1 to 0.3 mm; the buffer section is sleeved with an elastic buffer assembly; the elastic buffer assembly includes a memory alloy gasket and a silicon copper alloy sleeve; the spiral angle of the pressure relief groove is 25-35°, and the ratio of the groove width to the groove depth of the pressure relief groove is 2:1 to 5:1; the elastic buffer assembly is provided with a temperature compensation structure.

6. A pressure relief pin valve die insert of claim 1 wherein: The outside of the injection nozzle is provided with an injection nozzle heating ring.

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