Liquid silicone rubber cold runner cold nozzle assembly

Abstract

The utility model discloses a kind of liquid silicone cold runner cold nozzle assemblies, comprising: needle, cold nozzle, cold water jacket are sequentially arranged from inside to outside;Cold water jacket is sleeved in the outside of cold nozzle, first gap is equipped between cold water jacket and cold nozzle, and the lateral wall of cold water jacket is equipped with the water hole being communicated with first gap;Cold nozzle inside is equipped with cavity, and needle is movably arranged in cavity.This technique, by setting cold water jacket outside cold nozzle, and setting first gap between cold water jacket and cold nozzle, and the lateral wall of cold water jacket is equipped with the water hole being communicated with first gap, injects cold water into first gap from water hole during operation, to maintain the temperature of cold nozzle as suitable temperature, avoid the vulcanization of silicone material inside the end of cold nozzle, not only this, by setting cold nozzle as titanium alloy cold nozzle, it is convenient for heat transfer, temperature control is more accurate.

Description

Technical Field

[0001] This utility model relates to the field of mold technology, and in particular to a liquid silicone cold runner nozzle assembly. Background Technology

[0002] Liquid silicone rubber injection molding (LSR) is a precision molding process for two-component liquid silicone rubber. Leveraging the material's advantages of being non-toxic, having excellent elasticity, and exhibiting strong environmental resistance, combined with the high efficiency and automation of injection molding, it is widely used in high-end fields such as medical, maternal and infant products, electronics, and automotive. Its core principle is to precisely control the material mixing, plasticizing injection, and mold curing processes to transform liquid silicone rubber into high-precision molded products.

[0003] Injection molding liquid silicone rubber (LSR) technology uses two-component liquid silicone rubber as raw material, and the product is obtained through a series of processes including raw material mixing, plasticizing injection molding, high-temperature curing, and mold opening and part removal. Specifically, liquid silicone is a two-component liquid material, consisting of component A and component B. The mixer thoroughly mixes component A and component B in a precise 1:1 ratio. Some colored products are also equipped with color pumps and color metering components. After the raw materials such as component A, component B, additives, and masterbatch are thoroughly mixed, they enter the plasticizing system. In the plasticizing system, the cross-linking reaction is triggered by high temperature, with a curing temperature of 170-200℃. Then, it flows into the mold cavity through the injection molding machine's cold nozzle, followed by curing and mold opening to obtain the finished product.

[0004] However, in liquid silicone injection molding, when the liquid silicone flows through the cold nozzle of the injection molding machine, the silicone in that area often fails to undergo the normal cross-linking and curing reaction, ultimately presenting a sticky, soft, and uncured state. This is mainly because, in the injection molding machine's gating system, the cold nozzle is the critical part closest to the mold gate. Its design intention is to maintain a low temperature to prevent the silicone material from curing prematurely in non-cavity areas, thus preventing gate blockage and affecting continuous injection. However, precisely because the temperature in this area is much lower than the mold's curing temperature of 170-200℃, and LSR curing highly depends on high temperature to trigger the cross-linking reaction, this creates a structural vulnerability for non-curing in this area. Especially when the silicone stays at the cold nozzle for a slightly longer time, the low temperature environment inhibits the curing reaction, thus preventing the silicone material in this area from curing. Utility Model Content

[0005] In view of the shortcomings of related technologies, the purpose of this utility model is to provide a liquid silicone cold runner nozzle assembly, which aims to solve the technical problem that the silicone material at the nozzle head is prone to non-curing in related technologies.

[0006] This utility model discloses a liquid silicone cold runner nozzle assembly, comprising: a pin, a cold nozzle, and a cold water jacket arranged sequentially from the inside to the outside; the cold water jacket is fitted on the outside of the cold nozzle, and a first gap is provided between the cold water jacket and the cold nozzle, and a water hole communicating with the first gap is provided on the side wall of the cold water jacket; a cavity is provided inside the cold nozzle, and a first opening is provided at the end of the cold nozzle, and the cavity and the first opening are communicating; the pin is movably disposed in the cavity so that the pin can block or open the first opening.

[0007] The cavity is disposed inside the cold nozzle and includes a first cavity, a second cavity, and a third cavity connected in sequence. The inner diameter of the first cavity is larger than that of the third cavity. The inner diameter of the second cavity gradually decreases from the first cavity to the third cavity. The inner shape of the third cavity is adapted to the local shape of the ejector pin.

[0008] Preferably, the cooling nozzle is a titanium alloy cooling nozzle.

[0009] Specifically, the cold water jacket includes: a first sleeve, the side wall of the first sleeve is provided with water holes, the water holes include water inlet holes and water outlet holes, the water inlet holes and water outlet holes are symmetrically arranged on the side wall of the first sleeve, and the water inlet holes, the first gap and the water outlet holes are connected.

[0010] The ejector pin includes: an ejector pin body, a mounting part, and a tip part. The mounting part and the tip part are respectively connected to opposite ends of the ejector pin body. The ejector pin body is located inside the cavity. The tip part is located inside the third cavity, and the shape of the tip part is adapted to the internal shape of the third cavity.

[0011] Specifically, the diameter of the tip gradually decreases from the body of the ejector pin towards the direction away from the body of the ejector pin.

[0012] Specifically, the cold nozzle assembly also includes a cold nozzle module. The cold nozzle module has a first groove, the shape of which is adapted to the shape of the end of the cold nozzle. The bottom of the first groove has a pin hole that penetrates the cold nozzle module, the shape of which is adapted to the shape of the tip.

[0013] Preferably, the end of the tip furthest from the mounting portion is flat.

[0014] The inner diameter of the first groove gradually decreases from the direction closer to the cold water jacket to the direction farther away from the cold water jacket.

[0015] The liquid silicone cold runner nozzle assembly disclosed in this utility model includes: a ejector pin, a cold nozzle, and a cold water jacket arranged sequentially from the inside to the outside; the cold water jacket is fitted over the outside of the cold nozzle, and a first gap is provided between the cold water jacket and the cold nozzle; the side wall of the cold water jacket has a water hole communicating with the first gap; the cold nozzle has a cavity inside, and the ejector pin is movably disposed in the cavity. In this technology, by setting a cold water jacket on the outside of the cold nozzle and setting a first gap between the cold water jacket and the cold nozzle, and the side wall of the cold water jacket has a water hole communicating with the first gap, cold water is injected into the first gap through the water hole during operation to maintain the temperature of the cold nozzle at a suitable temperature, preventing the silicone material inside the end of the cold nozzle from vulcanizing. Moreover, by setting the cold nozzle to a titanium alloy cold nozzle, heat transfer is facilitated and temperature control is more precise. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without any innovative effort.

[0017] Figure 1 This is a connection structure diagram of the ejector pin, cooling nozzle, and cooling water jacket disclosed in the embodiments of this utility model; Figure 2 This is a cross-sectional view of the ejector pin, cooling nozzle, and cooling water jacket disclosed in the embodiments of this utility model; Figure 3 This is a connection structure diagram of the cold nozzle and cold water jacket disclosed in the embodiments of this utility model; Figure 4 This is a structural diagram of the upper mold, lower mold, and cold nozzle assembly disclosed in the embodiments of this utility model; Figure 5 The embodiments disclosed herein Figure 4 Enlarged view of the structure of section A; Figure label: 1000, Upper mold; 2000, Lower mold; 101, Drive mechanism; 201, Silicone mold cavity; 1, Ejector pin; 10, First gap; 11, Ejector pin body; 12, Mounting part; 13, Tip part; 2, Cooling nozzle; 21, Cavity; 211, First cavity; 212, Second cavity; 213, Third cavity; 22, First opening; 3, Cooling water jacket; 30, First sleeve; 31, Water hole; 311, Water inlet hole; 312, Water outlet hole; 4, Cooling nozzle module; 41, First groove; 42, Ejector pin hole; Detailed Implementation

[0018] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some, not all, of the embodiments of the present utility model. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model.

[0019] It should be understood that, when used in this specification and the appended claims, the terms “comprising” and “including” indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0020] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0021] It should also be further understood that the terms "and" and "or" as used in this specification and the appended claims refer to any combination of one or more of the associated listed items and all possible combinations, and include such combinations.

[0022] The above are merely specific embodiments of this utility model, but the protection scope of this utility model is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this utility model, and these modifications or substitutions should all be covered within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the scope of the claims.

[0023] This utility model discloses a liquid silicone cold runner nozzle assembly, such as... Figure 1-5As shown, it includes: a ejector pin 1, a cold nozzle 2, and a cold water jacket 3 arranged sequentially from the inside to the outside; the cold water jacket 3 is fitted over the outside of the cold nozzle 2, and a first gap 10 is provided between the cold water jacket 3 and the cold nozzle 2; the side wall of the cold water jacket 3 is provided with a water hole 31 communicating with the first gap 10; the cold nozzle 2 has a cavity 21 inside, and a first opening 22 is provided at the end of the cold nozzle 2; the cavity 21 and the first opening 22 are connected; the ejector pin 1 is movably disposed in the cavity 21 so that the ejector pin 1 blocks or opens the first opening 22. In this embodiment, the ejector pin 1 is partially disposed inside the cavity 21, and the driving mechanism 101 drives the ejector pin 1 to move within the cavity 21; in specific implementation, the cold nozzle 2 and the cold water jacket 3 are arranged... In the upper mold 1000, the silicone cavity 201 is located in the lower mold 2000. During injection molding, the silicone material is injected into the cavity 21. Cooling water enters the first gap 10 through the water hole 31 to cool the cold nozzle 2 and the silicone material inside the cold nozzle 2, so as to ensure that the temperature of the silicone material is at a suitable temperature. During injection, the drive mechanism 101 drives the ejector pin 1 to move away from the first opening 22. The silicone material flows out from the first opening 22 and is injected into the silicone cavity 201 of the lower mold 2000. When the injection is completed, the drive mechanism 101 drives the ejector pin 1 to move closer to the first opening 22 to block the first opening 22 and stop the injection of silicone material. Subsequently, the injection molded part in the silicone cavity 201 cools and is demolded.

[0024] Specifically, cavity 21 is disposed throughout the interior of cold nozzle 2. Cavity 21 includes a first cavity 211, a second cavity 212, and a third cavity 213 connected in sequence. The inner diameter of the first cavity 211 is larger than that of the third cavity 213. The inner diameter of the second cavity 212 gradually decreases from the first cavity 211 to the third cavity 213. The inner shape of the third cavity 213 is adapted to the local shape of the ejector pin 1. During injection molding, silicone material is injected through the first cavity 211. By setting the inner diameter of the second cavity 212 from... The first cavity 211 to the third cavity 213 gradually decrease in size, which can guide the silicone material to flow into the silicone mold cavity 201 through the second cavity 212, the third cavity 213 and the first opening 22. The ejector pin 1 is movably disposed inside the cavity 21. By setting the inner cavity shape of the third cavity 213 to match the local shape of the ejector pin 1, the ejector pin 1 can block or open the third cavity 213, thereby injecting silicone material into the silicone mold cavity 201 or terminating the injection of silicone material.

[0025] Among them, the cooling nozzle 2 is a titanium alloy cooling nozzle. Titanium alloy cooling nozzles have high hardness and wear resistance, which can extend the service life of the cooling nozzle 2. Moreover, it has a low thermal conductivity and more precise temperature control, which can effectively reduce the loss of heat from the melt to other parts of the mold and avoid flow channel blockage and product defects caused by premature cooling and solidification of the melt.

[0026] Specifically, the cooling water jacket 3 includes: a first sleeve 30, the side wall of the first sleeve 30 is provided with water holes 31, the water holes 31 include water inlet holes 311 and water outlet holes 312, the water inlet holes 311 and water outlet holes 312 are symmetrically arranged on the side wall of the first sleeve 30, the water inlet holes 311, the first gap 10 and the water outlet holes 312 are connected, during the injection molding process, cooling water enters the first gap through the water inlet holes 311 to cool the cold nozzle and the silicone material inside the cold nozzle, so as to ensure that the temperature of the silicone material is within a suitable temperature range.

[0027] Specifically, the ejector pin 1 includes: an ejector pin body 11, a mounting part 12, and a tip part 13. The mounting part 12 and the tip part 13 are respectively connected to opposite ends of the ejector pin body 11. The ejector pin body 11 is partially disposed inside the cavity 21. The tip part 13 is disposed inside the third cavity 213, and the shape of the tip part 13 is adapted to the internal shape of the third cavity 213. The mounting part 12 is connected to the drive mechanism 101 to drive the ejector pin 1 to move towards or away from the first opening 22.

[0028] The diameter of the tip 13 gradually decreases from the ejector body 11 toward the direction away from the ejector body 11, so that the tip 13 can be inserted into the third cavity 213 and the ejector hole.

[0029] The cold nozzle assembly also includes a cold nozzle module 4. Specifically, the cold nozzle module is fitted into the surface of the lower mold. The cold nozzle module 4 is provided with a first groove 41. The shape of the first groove 41 is adapted to the shape of the end of the cold nozzle 2. When the upper and lower molds are closed, the end of the cold nozzle 2 is embedded in the first groove 41. When the upper and lower molds are opened, the end of the cold nozzle 2 leaves the first groove 41. The bottom of the first groove 41 is provided with an ejector pin hole 42 that penetrates the cold nozzle module 4. The shape of the ejector pin hole 42 is adapted to the shape of the tip 13. When the injection ends, the drive mechanism 101 drives the ejector pin 1 to move towards the first opening 22. The tip 13 of the ejector pin 1 extends into the third cavity 213 and the ejector pin hole 42 in sequence to block the third cavity 213 and the ejector pin hole 42, thereby terminating the injection.

[0030] Specifically, the end of the tip 13 away from the mounting portion 12 is flat. During injection molding, the upper and lower molds are closed. During injection, the end of the cold nozzle 2 is embedded in the first groove 41. The drive mechanism 101 drives the ejector pin 1 to move away from the first opening 22. The silicone material flows through the first opening 22, the ejector pin hole 42 and into the silicone mold cavity 201 in sequence. When the injection ends, the drive mechanism 101 drives the ejector pin 1 to move closer to the first opening 22. The tip 13 of the ejector pin 1 extends into the ejector pin hole 42 until the end of the tip 13 away from the mounting portion 12 is flush with the surface of the cold nozzle module 4, so that the end of the silicone part in the silicone mold cavity 201 is flat.

[0031] Specifically, the inner diameter of the first groove 41 gradually decreases from near the cold water jacket 3 to far away from the cold water jacket 3. This arrangement facilitates the end of the cold nozzle 2 to extend into the first groove when the upper and lower molds are closed.

[0032] In specific implementation, ejector pin 1, cold nozzle 2, and cold water jacket 3 are located in the upper mold 1000, while cold nozzle module 4 and silicone mold cavity 201 are located in the lower mold 2000. Cold nozzle module 4 and silicone mold cavity 201 are located below and connected to cold nozzle module 4. The surface of cold nozzle module 4 and the end face of silicone mold cavity 201 are on the same plane. During injection molding, silicone material is injected into cavity 21. Cooling water enters the first gap 10 through water inlet 311 and flows out through water outlet 312 to cool cold nozzle 2 and the silicone material inside cold nozzle 2, so as to ensure that the temperature of silicone material is suitable. During injection, drive mechanism 101 drives ejector pin 1 to move away from the first opening 22, and silicone material flows out from the first opening 22 and is injected into the silicone mold cavity of the lower mold. When injection is completed, drive mechanism 101 drives ejector pin 1 to move closer to the first opening 22, blocking the first opening 22, stopping the injection of silicone material, and the injection molded part in silicone mold cavity 201 cools and demolds.

[0033] This utility model discloses a liquid silicone cold runner nozzle assembly, comprising: a ejector pin, a cold nozzle, and a cold water jacket arranged sequentially from the inside out; the cold water jacket is fitted over the outside of the cold nozzle, with a first gap between the cold water jacket and the cold nozzle, and a water hole communicating with the first gap on the side wall of the cold water jacket; the cold nozzle has an internal cavity, and the ejector pin is movably disposed within the cavity. In this technology, by setting a cold water jacket on the outside of the cold nozzle and establishing a first gap between the cold water jacket and the cold nozzle, and by providing a water hole communicating with the first gap on the side wall of the cold water jacket, cold water is injected into the first gap through the water hole during operation to maintain the temperature of the cold nozzle at a suitable temperature, preventing the silicone material inside the end of the cold nozzle from becoming sulfided. Furthermore, by using a titanium alloy cold nozzle, heat transfer is facilitated, and temperature control is more precise.

[0034] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any equivalent modifications or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A liquid silicone cold runner nozzle assembly, characterized in that, include: The components are arranged sequentially from the inside out: a ejector pin, a cold nozzle, and a cold water jacket. The cold water jacket is fitted over the outside of the cold nozzle, and there is a first gap between the cold water jacket and the cold nozzle. The side wall of the cold water jacket is provided with a water hole that communicates with the first gap. The cold nozzle has a cavity inside, and a first opening is provided at the end of the cold nozzle. The cavity and the first opening are connected. The ejector pin is movably disposed in the cavity so that the ejector pin can block or open the first opening.

2. The liquid silicone cold runner nozzle assembly according to claim 1, characterized in that, The cavity is disposed inside the cold nozzle. The cavity includes a first cavity, a second cavity, and a third cavity connected in sequence. The inner diameter of the first cavity is larger than that of the third cavity. The inner diameter of the second cavity gradually decreases from the first cavity to the third cavity. The inner shape of the third cavity is adapted to the local shape of the ejector pin.

3. The liquid silicone cold runner nozzle assembly according to claim 2, characterized in that, The cooling nozzle is a titanium alloy cooling nozzle.

4. The liquid silicone cold runner nozzle assembly according to claim 1, characterized in that, The cold water jacket includes: a first sleeve, the side wall of the first sleeve is provided with water holes, the water holes include water inlet holes and water outlet holes, the water inlet holes and water outlet holes are symmetrically arranged on the side wall of the first sleeve, and the water inlet holes, the first gap and the water outlet holes are connected.

5. The liquid silicone cold runner nozzle assembly according to claim 2, characterized in that, The ejector pin includes: an ejector pin body, a mounting part, and a tip part, with the mounting part and the tip part respectively connected to opposite ends of the ejector pin body; the ejector pin body is located inside the cavity; The tip is located inside the third cavity, and the shape of the tip is adapted to the internal shape of the third cavity.

6. The liquid silicone cold runner nozzle assembly according to claim 5, characterized in that, The diameter of the tip gradually decreases from the body of the ejector pin to the direction away from the body of the ejector pin.

7. The liquid silicone cold runner nozzle assembly according to claim 5, characterized in that, It also includes a cold nozzle module, which has a first groove whose shape matches the shape of the end of the cold nozzle. The bottom of the first groove has a pin hole that passes through the cold nozzle module, and the shape of the pin hole matches the shape of the tip.

8. The liquid silicone cold runner nozzle assembly according to claim 5, characterized in that, The end of the tip that is away from the mounting part is flat.

9. The liquid silicone cold runner nozzle assembly according to claim 7, characterized in that, The inner diameter of the first groove gradually decreases from the direction closer to the cold water jacket to the direction farther away from the cold water jacket.

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