Negative pressure fixed insert connector injection molding mold

Abstract

The invention relates to the technical field of injection molds, in particular to a negative pressure fixed insert connector injection molding mold. The mold sequentially comprises a panel, a discharging plate, a fixed mold plate, a movable mold plate, an ejector pin plate and a bottom plate from top to bottom, a mold cavity is formed between the fixed mold plate and the movable mold plate, an injection molding nozzle extending downwards to the mold cavity is installed on the panel, and an ejector pin is installed on the ejector pin plate; an air exhaust main pipe is arranged in the bottom plate, and a plurality of air exhaust branch pipes extending upwards to the bottom of the cavity are connected to the air exhaust main pipe; an inflation header pipe is arranged in the panel, and a plurality of inflation branch pipes extending downwards to the top of the cavity are connected to the inflation header pipe; a first sealing piece is arranged at the end, facing the cavity, of the air exhaust branch pipe, and a second sealing piece is arranged at the end, facing the cavity, of the air inflation branch pipe. The technical problems that in the prior art, vacuumizing and air blowing share one set of pipeline in a negative pressure injection molding mold, pollutants sucked out of a mold cavity are easily blown back into the mold cavity again, cross contamination is generated, and the product quality is poor are effectively solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of injection mold, in particular to a negative pressure fixed insert connector injection molding mold. BACKGROUND

[0002] The principle of the negative pressure injection molding mold is to control the gas flow in the mold cavity through the negative pressure valve, so that the gas is extracted from the cavity to generate negative pressure, so that the molten plastic can be more fully filled in the mold cavity, reducing defects such as gas residue and shrinkage, thereby improving the density and surface finish of the molded product. However, for thin-walled molded parts, the existing negative pressure injection molding mold only relies on the ejector rod to eject it during demolding, resulting in deformation and damage during demolding, and poor demolding quality.

[0003] To this end, the patent document with the authorized announcement number CN103302813B discloses a plastic product negative pressure injection molding mold and its method, which includes a front mold and a rear mold cooperating with the front mold, the rear mold is arranged on the rear end surface of the front mold, the inside of the front mold is provided with a plurality of cavities, the front end surface of the front mold is provided with an additional plate, a plurality of air holes corresponding to the plurality of cavities are opened on the additional plate, each air hole is in communication with the corresponding cavity, the plurality of air holes are in communication with each other through an air passage, the air passage is in communication with the external air compression system; a plurality of mold cores are detachably arranged inside the front mold, the cavities are arranged in the mold cores; the mold core includes an outer core and at least one combined inner core arranged inside the front end of the outer core, the combined inner core and the outer core are mutually enclosed to form a cavity, the air hole is threadedly connected with an adjusting screw, the rear end of the adjusting screw is pressed against the frontmost combined inner core, the adjusting screw is a hollow tubular structure, and the two ends of the hollow inner cavity of the adjusting screw are in communication with the air hole and the cavity, respectively.

[0004] The mold can form negative pressure by sucking air in the cavity through an air compression system during injection molding, and can also blow air into the cavity through the air compression system during demolding to make the product separate from the front mold, thereby improving demolding quality and efficiency. However, the mold described above uses a set of air vent channels for both sucking air in the cavity and blowing air into the cavity, which has the following problems during use: 1. During the vacuum extraction stage, pollutants such as air, plastic volatiles, and micro-droplets formed by evaporation of raw material moisture in the cavity will be discharged through the air vent channels, and are prone to adhere and remain in the air vent channels during the discharge process. During the subsequent air blowing stage, the high-pressure airflow will flush the air vent channels in the opposite direction, which will bring the remaining oil stains, carbides, or condensed water back into the cavity, affecting the quality of the injection molded product; 2. During the parameter adjustment stage (such as mold testing or material replacement), due to unstable injection speed and holding pressure, the plastic melt is prone to partial leakage or excessive filling, which will leave residues in the cavity. These residues will enter the air vent channels during the process of sucking air in the cavity, and will enter the cavity with the high-pressure airflow during the process of blowing air into the cavity, and will again be left in the cavity, affecting the quality of the subsequent injection molded product. In addition, the air vent channels need to meet the dual requirements of vacuum extraction (high air tightness) and air blowing (anti-pollution). During vacuum extraction, a narrow slit structure or a micro-porous filter screen is usually used to reduce gas leakage and ensure stable vacuum degree. During air blowing, the channel width needs to be increased to improve demolding efficiency. The mold described above uses the same set of air vent channels for both vacuum extraction and air blowing, which is difficult to meet the dual requirements of vacuum extraction and air blowing. SUMMARY

[0005] The present application provides a kind of negative pressure fixed embedded piece connector injection molding mold, to solve the technical problems that the product quality is poor in the prior art negative pressure injection molding mold, the vacuum extraction and air blowing share a set of pipeline, and the pollutants sucked in the cavity are blown back into the cavity, cross contamination occurs.

[0006] To solve the above problems, the negative pressure fixed embedded piece connector injection molding mold provided by the present application adopts the following technical scheme: A kind of negative pressure fixed embedded piece connector injection molding mold, including faceplate, stripper plate, fixed mold plate, movable mold plate, ejector plate and bottom plate arranged in sequence from top to bottom, the fixed mold plate and the movable mold plate form a cavity, the faceplate is installed with injection nozzle extending downward to the cavity, the ejector plate is installed with ejector pin, further comprising: The air extraction pipeline includes an air extraction main pipe arranged in the bottom plate, a plurality of air extraction branch pipes extending upward to the bottom of the cavity are connected to the air extraction main pipe, and the inlet of the air extraction main pipe is connected to an air extraction device; The air filling pipeline includes an air filling main pipe arranged in the faceplate, a plurality of air filling branch pipes extending downward to the top of the cavity are connected to the air filling main pipe, and the inlet of the air filling main pipe is connected to an air filling device; The first seal is arranged at one end of the cavity, and the second seal is arranged at one end of the cavity.

[0007] The negative pressure fixed insert connector injection molding mold has the following beneficial effects: 1. The gas in the cavity can be extracted by arranging the extraction pipeline in the lower part of the mold, so that the cavity becomes a vacuum state, so that the molten plastic can more fully fill the cavity, avoiding insufficient injection or internal bubbles, holes and other defects of the injection product, to improve the quality and yield of the injection product, and after the cavity is vacuumized, the molten plastic can more quickly contact the mold wall and transfer heat, shortening the cooling and solidification time of the molten plastic in the cavity, which helps to improve the production efficiency of the injection product and shorten the production cycle. 2. By arranging the gas filling pipeline in the upper part of the mold, gas can be blown into the cavity through the gas filling pipeline to ensure that the gas is evenly distributed above the cavity, and a layer of gas film is quickly formed between the injection product and the mold wall, reducing the friction between the injection product and the mold, making the injection product more easily removed from the mold, significantly improving the demolding efficiency and demolding quality, and shortening the production cycle. 3. By arranging the gas filling pipeline and the extraction pipeline in the upper and lower parts of the mold respectively, the space inside the mold can be fully utilized, and the mold structure is more compact and reasonable. At the same time, the independent arrangement of the gas filling pipeline and the extraction pipeline can avoid cross contamination between them, and during the daily maintenance and maintenance of the mold, the extraction pipeline and the gas filling pipeline can be checked, cleaned and repaired respectively, without the need to disassemble the entire mold, thereby reducing the maintenance cost, improving the work efficiency, and ensuring the production quality of the injection product.

[0008] Through the above arrangement, the present application improves and upgrades the existing negative pressure injection molding mold, effectively solves the technical problem that the existing negative pressure injection molding mold shares a pipeline for vacuum extraction and gas blowing, which easily blows the pollutants sucked out of the cavity back into the cavity, causing cross contamination and resulting in poor product quality.

[0009] Further, the radial dimensions of the plurality of gas filling branch pipes increase in sequence along the flow direction of the gas in the gas main pipe.

[0010] Beneficial effects: the radial size of the plurality of inflation branch pipes gradually increases along the flow direction of the gas in the inflation main pipe, which can make the gas more evenly distributed to each inflation branch pipe during the flow process, avoid the accumulation or uneven distribution of the gas at the end of the inflation main pipe, and ensure that each part of the injection molding product can be fully inflated when demolding; as the radial size of the inflation branch pipe increases, the gas flow rate gradually decreases at the inlet of the inflation branch pipe, which helps to reduce the flow rate and resistance of the gas in the inflation branch pipe, reduces the friction between the gas and the inner wall of the inflation branch pipe, thereby reducing the energy loss during the gas flow process, making the gas flow more stable, and improving the demolding efficiency.

[0011] Further, the radial size of the plurality of suction branch pipes gradually decreases along the flow direction of the gas in the suction main pipe.

[0012] Beneficial effects: the radial size of the plurality of suction branch pipes gradually decreases along the flow direction of the gas in the suction main pipe, which can improve the suction efficiency, and the gradual decrease in the radial size of the suction branch pipe helps to form a gradually accelerated effect during the gas flow process, ensuring that the gas can be extracted from the cavity more quickly and effectively; in addition, the gradual decrease in the radial size of the plurality of suction branch pipes along the flow direction of the gas in the suction main pipe can also optimize the gas extraction path and enhance the uniformity of the suction, ensuring that the gas in the cavity can be uniformly extracted at each position, which helps to avoid the problems of gas residue or uneven distribution in the cavity, improve the product quality, and ensure that the gas flows along a smoother path during the suction process, avoiding the accumulation of gas in the suction branch pipe or the formation of vortex at the connection between the suction branch pipe and the suction main pipe, thereby improving the efficiency and uniformity of the gas extraction.

[0013] Further, the inflation main pipe is an annular pipe distributed along the outer periphery of the injection nozzle.

[0014] Further, a control valve is installed at the bottom end of the injection nozzle to control the injection of molten plastic into the cavity.

[0015] Further, the control valve is a throttle valve, which includes a fixed shaft fixedly installed in the injection nozzle, a first sleeve and a second sleeve mounted on the fixed shaft, a first valve plate and a second valve plate fixedly installed on the first sleeve and the second sleeve respectively, a first elastic member arranged between the fixed shaft and the first sleeve, and a second elastic member arranged between the fixed shaft and the second sleeve.

[0016] Beneficial effects: By installing a throttle valve at the bottom of the injection nozzle, precise regulation of the injection flow rate can be achieved, resulting in uniform injection and ensuring the consistency and stability of the injection molded product quality. During injection, molten plastic flows into the cavity. When passing through the throttle valve, the first and second valve plates are forced to rotate towards the cavity, compressing the first and second elastic elements. The molten plastic flows into the cavity through the gap between the first and second valve plates and the inner wall of the cavity. When the cavity is filled with molten plastic, the pressure inside the cavity and the injection nozzle gradually balances. Under the elastic restoring force of the first and second elastic elements, the first and second valve plates rotate towards the side away from the cavity until they return to their initial state, preventing molten plastic from continuing to enter the cavity.

[0017] Furthermore, the first valve plate includes an arc-shaped plate with its straight edge facing the fixed shaft, and a connecting plate for connecting with the first sleeve is provided on the straight edge. The arc-shaped edge of the arc plate matches the inner circumference of the injection nozzle. The second valve plate has the same structure as the first valve plate, and the first valve plate and the second valve plate are centrally symmetrical about the center of the fixed shaft in the length direction.

[0018] Beneficial effects: The first and second valve plates are centrally symmetrical about the center of the fixed axis, making the overall structure of the throttle valve more compact and ensuring the balance of the throttle valve when opening and closing. This effectively reduces the additional stress and wear caused by asymmetry. The connecting plate on the straight edge is connected to the sleeve, which is simple and reliable and can withstand greater pressure and torque, ensuring the stability and durability of the valve during opening and closing.

[0019] Furthermore, both the first elastic element and the second elastic element are coil springs.

[0020] Beneficial effects: The coil spring can store a large amount of elastic potential energy in a limited space, and can dynamically balance the influence of fluid pressure fluctuations on the valve core position through the elastic torque compensation mechanism. Under the condition of sudden pressure change, its elastic potential energy can offset part of the transient impact force, reduce the opening fluctuation amplitude, and thus maintain the stability of fluid flow output.

[0021] Furthermore, the first elastic element and the second elastic element are respectively sleeved at both ends of the fixed shaft along its length.

[0022] Furthermore, the ejector pin extends upward from the ejector plate to the bottom of the cavity.

[0023] The beneficial effects of the negative pressure fixing insert connector injection molding die provided by this invention are: 1. By setting up independent air charging pipeline and air exhausting pipeline in the upper and lower part of the negative pressure injection mold respectively, the internal space of the mold is fully utilized, and the air charging pipeline or air exhausting pipeline can be maintained separately, reducing the possibility of cross contamination; the air charging pipeline located above the cavity blows gas into the cavity to quickly and uniformly form a gas film between the injection product and the mold wall, thereby reducing the friction between the injection product and the mold wall, improving the demolding efficiency and quality; the air exhausting pipeline located below the cavity quickly exhausts the gas in the cavity, making the cavity become a vacuum state, so that the molten plastic can be more fully and uniformly filled in the cavity, reducing the risk of defects such as bubbles and holes in the injection product, improving the quality and yield of the injection product, while shortening the cooling and solidification time of the molten plastic in the cavity, improving the production efficiency of the injection product; 2. In the air charging pipeline, the radial size of the multiple air charging branch pipes is designed to gradually increase along the flow direction of the gas in the air charging manifold, when the gas enters the air charging manifold, the radial size of the air charging branch pipe continuously expands, and the increase of the inlet cross-sectional area of the air charging branch pipe gradually attenuates the flow rate of the gas, thereby avoiding the turbulence accumulation phenomenon at the end of the air charging branch pipe due to the sudden drop in flow rate, ensuring the uniformity of the gas distribution in the flow process to each air charging branch pipe, thereby ensuring that each part of the injection product can be fully aerated during demolding, improving the demolding efficiency while ensuring the demolding quality; at the same time, as the radial size of the air charging branch pipe gradually increases, the flow rate of the gas at the inlet of each air charging branch pipe gradually decreases, which can reduce the flow rate and resistance of the gas in the air charging branch pipe, reduce the friction between the gas and the inner wall of the air charging branch pipe, thereby reducing the energy loss in the gas flow process, improving the stability of the gas flow, and improving the demolding efficiency; 3. In the air exhausting pipeline, the radial size of the multiple air exhausting branch pipes is designed to gradually decrease along the flow direction of the gas in the air exhausting manifold, during the vacuumizing process, the vacuum pump forms negative pressure at the inlet of the air exhausting manifold, as the radial size of the air exhausting branch pipe gradually decreases, the flow rate of the gas is multiplied step by step, so that the gas in the cavity can be more quickly and effectively exhausted, thereby eliminating the vortex stagnation phenomenon at the end of the air exhausting branch pipe due to insufficient flow rate, improving the efficiency of gas extraction while improving the uniformity of gas extraction; the radial size of the multiple air exhausting branch pipes gradually decreases along the flow direction of the gas in the air exhausting manifold, which can optimize the gas extraction path, make the gas flow along a smoother path, and enhance the uniformity of gas flow during the air extraction process, so that the gas at each position in the cavity can be fully extracted, thereby avoiding the problems of gas residue or uneven distribution in the cavity, and ultimately improving the quality of the injection product; 4. By installing a throttle valve at the bottom of the injection nozzle and setting the throttle valve to include a fixed shaft and a first sleeve and a second sleeve fitted on the fixed shaft, and fixing the first valve plate and the second valve plate on the first sleeve and the second sleeve respectively, during the injection process, the pressure of the molten plastic flowing downward forces the first valve plate and the second valve plate to rotate, so that the molten plastic can flow into the cavity from the gap between the first valve plate and the second valve plate and the inner wall of the cavity. By installing an elastic element in the first sleeve and the second sleeve, the pressure of the molten plastic flowing downward forces the elastic element to compress. After the pressure in the cavity and the injection nozzle is balanced, the elastic restoring force of the elastic element forces the first valve plate and the second valve plate to return to their original position. This allows for precise adjustment of the injection flow rate, ensuring the consistency and stability of the injection molded product quality. 5. In the throttle valve, by setting the first valve plate and the second valve plate in a centrally symmetrical form about the center of the fixed axis length direction, a dynamic torque balance system is constructed while improving the overall structural compactness of the throttle valve. When the first valve plate and the second valve plate open and close, the symmetrical arrangement makes the radial force acting on the valve body symmetrically distributed, and the resultant force approaches zero. This can effectively reduce the additional stress and wear caused by asymmetry, thereby extending the service life of the throttle valve. By setting a connecting plate connected to the sleeve on the straight edge, the connection is simple and reliable, and can withstand large pressure and torque, ensuring the stability and durability of the valve during opening and closing.

[0024] In summary, this invention has improved and upgraded existing negative pressure injection molding dies, effectively solving the technical problem that in existing negative pressure injection molding dies, vacuuming and blowing share a single pipeline, which easily causes contaminants sucked out of the cavity to be blown back into the cavity, resulting in cross-contamination and poor product quality. Attached Figure Description

[0025] Figure 1 This is an isometric view of the injection molding mold for the negative pressure fixing insert connector provided by the present invention. Figure 2 This is a front view of the injection molding mold for the negative pressure fixing insert connector provided by the present invention; Figure 3 This is a schematic diagram of the internal structure of the injection molding mold for the negative pressure fixing insert connector provided by the present invention. Figure 4 for Figure 3 A magnified view of a portion of point A in the middle; Figure 5 This is an isometric view of the throttle valve in the injection molding die of the negative pressure fixing insert connector provided by the present invention; Figure 6 This is a schematic diagram of the internal structure of the throttle valve in the injection molding mold of the negative pressure fixing insert connector provided by the present invention. Figure 7 This is a schematic diagram showing the arrangement of the air manifold in the panel of the injection molding mold for the negative pressure fixing insert connector provided by the present invention.

[0026] Explanation of reference numerals in the attached figures: 1. Panel; 2. Unloading plate; 3. Fixed mold plate; 4. Moving mold plate; 5. Ejector plate; 6. Base plate; 7. Cavity; 8. Injection nozzle; 9. Ejector pin; 10. Main suction pipe; 11. Branch suction pipe; 12. Main inflation pipe; 13. Branch inflation pipe; 14. Second seal; 15. Throttling valve; 16. Fixed shaft; 17. First sleeve; 18. Second sleeve; 19. First valve plate; 20. Second valve plate; 21. First elastic element; 22. Second elastic element. Detailed Implementation

[0027] An embodiment of the injection molding die for the negative pressure fixing insert connector provided by the present invention: like Figures 1 to 3 As shown, the injection molding mold for a negative pressure fixed insert connector includes, from top to bottom, a panel 1, a stripper plate 2, a fixed template 3, an ejector plate 5, and a base plate 6. A cavity 7 is formed between the fixed template 3 and the moving template 4 to compact and shape the molten plastic into the desired form. An injection nozzle 8 extending downwards into the cavity 7 is mounted on the panel 1, and ejector pins 9 extending upwards to the bottom of the cavity 7 are mounted on the ejector plate 5. Furthermore, the mold also includes an air extraction pipe extending upwards to the bottom of the cavity 7 and an air inflation pipe extending downwards to the top of the cavity 7.

[0028] The following describes the structural components of the air extraction pipeline and its arrangement within the mold. For example... Figure 3 As shown, the evacuation pipeline includes a main evacuation pipe 10 horizontally arranged within the base plate 6 and extending from left to right. Multiple branch evacuation pipes 11 extending upwards to the bottom of the cavity 7 are connected to the main evacuation pipe 10. An evacuation device is connected to the inlet (i.e., the left end) of the main evacuation pipe 10. In this embodiment, the radial dimensions of the multiple branch evacuation pipes 11 decrease sequentially along the gas flow direction within the main evacuation pipe 10, i.e., decreasing sequentially from right to left. This creates a negative pressure at the inlet of the main evacuation pipe 10 during the vacuuming process, causing the gas flow rate to gradually increase as the radial dimensions of the branch evacuation pipes 11 decrease. This creates a gradual acceleration effect during gas flow, ensuring that the gas can be extracted from the cavity 7 more quickly and effectively, enhancing the uniformity of evacuation, avoiding gas residue or uneven distribution within the cavity 7, ensuring the vacuum level within the cavity 7, and improving the quality of the injection molded product. In other embodiments, the radial dimensions of the multiple branch evacuation pipes 11 are the same.

[0029] The gas extraction pipeline is arranged at the lower part inside the mold, which can extract the gas in the cavity 7, so that the cavity 7 is in a vacuum state, thereby ensuring that the molten plastic can be more fully and uniformly filled in the cavity 7, avoiding the problems of insufficient injection amount or bubbles, holes and other defects in the injection product, thereby improving the quality of the injection product. In addition, after the cavity 7 is vacuumized, the molten plastic can be more quickly in contact with the inner wall of the mold and rapidly transfer heat, thereby shortening the cooling and solidification time of the molten plastic in the cavity 7, which is helpful to improve the production efficiency of the injection product and shorten the production cycle.

[0030] However, in the process of extracting the air in the cavity 7 through the gas extraction pipeline, the plastic particles in the cavity 7 may be extracted together with the gas, especially when the injection parameters are adjusted or the molten plastic contains some moisture, it is more likely that the plastic particles will be left in the cavity 7. These plastic particles will accumulate in the gas extraction pipeline during the extraction process, gradually clogging the pipeline, affecting the extraction efficiency, and as the clogging intensifies, the gas extraction pipeline may even completely lose its function, resulting in that the air in the cavity 7 cannot be effectively discharged, affecting the molding quality and injection efficiency of the insert connector. When the plastic particles flow in the pipeline, they will also rub against the pipeline wall, causing the pipeline to wear or break. After the plastic particles enter the gas extraction pipeline, they will also enter the gas extraction equipment with the gas, affecting the normal operation of the gas extraction equipment and increasing the maintenance cost of the gas extraction equipment.

[0031] Therefore, in order to avoid the above problems, a first sealing member is arranged at the end (i.e. the upper end) of the gas extraction branch pipe 11 facing the cavity 7, so as to prevent the plastic particles from entering the gas extraction branch pipe 11, thereby avoiding the situation that the plastic particles enter the gas extraction main pipe 10 and the gas extraction equipment.

[0032] Specifically, the first sealing member is an aluminum sheet which is attached to the inlet of the upper end of the gas extraction branch pipe 11 to prevent the plastic particles from entering the gas extraction branch pipe 11, thereby avoiding the situation that the plastic particles clog the gas extraction pipeline.

[0033] Next, the structure and arrangement of the gas filling pipeline in the mold will be introduced. As shown in Figure 3 The gas extraction pipeline includes a gas filling main pipe 12 arranged horizontally in the panel 1 and extending from left to right, a plurality of gas filling branch pipes 13 connected to the gas filling main pipe 12 and extending downward to the top of the cavity 7, and a gas filling device connected to the inlet (i.e. the left end) of the gas filling main pipe 12. The gas filling main pipe 12 is an annular pipe (as shown in Figure 7In the present embodiment, the radial dimension of the plurality of gas-filled branch pipes 13 gradually increases in the direction of gas flow in the gas-filled manifold 12, i.e., gradually increases from left to right, so as to gradually reduce the flow rate of the gas from left to right, reduce the flow rate and resistance of the gas in the gas-filled branch pipes 13, reduce the friction between the gas and the inner wall of the gas-filled branch pipes 13, thereby reducing the energy loss during the gas flow, making the gas flow more stable, and improving the demolding efficiency; in other embodiments, the radial dimensions of the plurality of gas-filled branch pipes 13 are the same.

[0034] The gas-filled pipeline is arranged at the upper portion inside the mold, gas can be blown into the cavity 7 through the gas-filled pipeline, ensuring that the gas can be uniformly distributed above the cavity 7, and a layer of gas film can be quickly formed between the injection molded product and the inner wall of the mold, reducing the friction between the injection molded product and the mold, making the injection molded product more easily demolded from the mold, thereby significantly improving the demolding efficiency and quality, and shortening the production cycle of the injection molded product.

[0035] However, in the process of filling gas into the cavity 7 through the gas-filled pipeline to assist in demolding, when the flow rate of the gas in the gas-filled pipeline is too high or the pressure changes sharply, strong airflow disturbance is easily generated, which will cause the plastic particles attached in the cavity 7 to be scoured and be sucked into the gas-filled pipeline, and even into the gas-filling equipment. With the continuous accumulation of plastic particles in the gas-filled pipeline, the gas-filled pipeline will be blocked, affecting the circulation of the gas, thereby affecting the supply of gas during demolding, and ultimately causing the embedded connector to be damaged during demolding, or the demolding to be incomplete.

[0036] Therefore, in order to avoid the above problems, the second sealing member 14 is arranged at the end (i.e., the lower end) of the gas-filled branch pipe 13 facing the cavity 7, so as to prevent the plastic particles from entering the gas-filled branch pipe 13, thereby avoiding the situation that the plastic particles enter the gas-filled manifold 12 and the gas-filling equipment, and ensuring the quality of the embedded connector.

[0037] Specifically, the second sealing member 14 is a sealing ring.

[0038] In addition, as shown in Figure 4 A control valve is further installed at the bottom end of the injection nozzle 8 to control the injection of molten plastic into the cavity 7.

[0039] Specifically, as shown in Figure 5 and Figure 6As shown, the control valve is a throttle valve 15, which comprises a fixed shaft 16 fixedly installed in the injection nozzle 8, a first sleeve 17 and a second sleeve 18 are sleeved on the fixed shaft 16, a first valve plate 19 and a second valve plate 20 are fixedly installed on the first sleeve 17 and the second sleeve 18 respectively, a first elastic member 21 is arranged between the fixed shaft 16 and the first sleeve 17, and a second elastic member 22 is arranged between the fixed shaft 16 and the second sleeve 18. In the process of injection molding, the pressure of the downward flow of the molten plastic is used to drive the first valve plate 19 and the second valve plate 20 to rotate around the fixed shaft 16, so that the molten plastic can enter the cavity 7 from the gap between the first valve plate 19 and the inner wall of the cavity 7 and the gap between the second valve plate 20 and the inner wall of the cavity 7, and at the same time, the first elastic member 21 and the second elastic member 22 are compressed under the pressure of the downward flow of the molten plastic, and when the pressure in the cavity 7 is balanced with the pressure in the injection nozzle 8, the elastic restoring force of the first elastic member 21 and the second elastic member 22 can drive the first valve plate 19 and the second valve plate 20 to restore to the original position, thereby realizing accurate adjustment of the injection flow.

[0040] The first valve plate 19 comprises an arc-shaped plate, the straight edge of the arc-shaped plate faces the fixed shaft 16, and the straight edge is provided with a connecting plate connected with the first sleeve 17, and the arc-shaped edge of the arc-shaped plate matches the inner circumference of the injection nozzle 8; the second valve plate 20 has the same structure as the first valve plate 19, and the two are centrally symmetric about the center of the fixed shaft 16 in the length direction, can improve the compactness of the overall structure of the throttle valve 15, and construct a dynamic torque balance system, so that the radial force acting on the valve body can be symmetrically distributed, the resultant force of the two is close to zero, the additional stress and wear caused by asymmetry are reduced, and the service life of the throttle valve 15 is prolonged.

[0041] In the embodiment, the first elastic member 21 and the second elastic member 22 are both coil springs, and the first elastic member 21 and the second elastic member 22 are respectively sleeved on both ends of the fixed shaft 16 in the length direction, the coil spring is a product for continuously providing a larger restoring force in a small space, and can use an elastic torque compensation mechanism to ensure the stability of the valve core position; in other embodiments, the first elastic member 21 and the second elastic member 22 are both shape memory alloys, the first elastic member 21 is sleeved on the fixed shaft 16 and located between the first sleeve 17 and the fixed shaft 16, the length of the first elastic member 21 is consistent with the length of the first sleeve 17, and the second elastic member 22 is sleeved on the fixed shaft 16 and located between the second sleeve 18 and the fixed shaft 16, the length of the second elastic member 22 is consistent with the length of the second sleeve 18.

[0042] It should be noted that, unless otherwise specified, the injection molded product in the present application refers to an insert connector.

[0043] The working principle of the negative pressure fixed insert connector injection molding mold provided by the present application is: Before injection molding, the air in the cavity 7 is sequentially extracted from the cavity 7 through the air extraction branch pipe 11 and the air extraction main pipe 10 by starting the air extraction device to perform vacuumizing operation, and the cavity 7 is in a vacuum state; then, the air extraction device is closed, and the molten plastic enters the cavity 7 from the injection nozzle 8 through the throttle valve 15, when the molten plastic passes through the throttle valve 15, the first valve plate 19 and the second valve plate 20 are forced to rotate towards the cavity 7, the first elastic member 21 and the second elastic member 22 are compressed, and the molten plastic flows into the cavity 7 from the gap between the first valve plate 19 and the second valve plate 20 and the inner wall of the cavity 7, when the cavity 7 is filled with the molten plastic, the pressure in the cavity 7 and the injection nozzle 8 gradually balances, then, the first valve plate 19 and the second valve plate 20 are rotated away from the cavity 7 under the elastic restoring force of the first elastic member 21 and the second elastic member 22 until they return to the initial state, preventing the molten plastic from continuing to enter the cavity 7; when demolding, the ejector pin 9 moves upward to a predetermined position, and the air charging device is started synchronously, and the gas provided by the air charging device enters the cavity 7 through the air charging main pipe 12 and the air charging branch pipe 13 in sequence, assisting the ejector pin 9 to complete the demolding of the injection molded product (i.e. the embedded connector).

[0044] According to the above description of the present specification, those skilled in the art can also understand that the terms used such as "upper", "lower", "front", "back", "left", "right" and the like indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the drawings of the present specification, and are only for the purpose of facilitating the description of the present application and simplifying the description, therefore the above orientation or positional relationship terms cannot be understood or interpreted as a limitation on the present application.

[0045] In addition, in the description of the present specification, the meaning of "a plurality of" is at least two, such as two, three or more, etc., unless otherwise explicitly specifically limited.

Claims

1. A negative pressure fixing insert connector injection molding die, comprising, from top to bottom, a panel, a stripper plate, a fixed mold plate, a movable mold plate, an ejector plate, and a base plate, wherein a cavity is formed between the fixed mold plate and the movable mold plate, an injection nozzle extending downward into the cavity is mounted on the panel, and ejector pins are mounted on the ejector plate, characterized in that, Also includes: The air extraction pipeline includes a main air extraction pipe disposed in the base plate, a plurality of air extraction branch pipes extending upward to the bottom of the cavity connected to the main air extraction pipe, and an air extraction device connected to the inlet of the main air extraction pipe. The inflation pipeline includes an inflation main pipe disposed in the panel, a plurality of inflation branch pipes extending downward to the top of the cavity connected to the inflation main pipe, and an inflation device connected to the inlet of the inflation main pipe. The end of the air extraction branch pipe facing the cavity is provided with a first sealing element, and the end of the air inflation branch pipe facing the cavity is provided with a second sealing element; The radial dimensions of the plurality of the inflation branch pipes increase sequentially along the flow direction of the gas in the inflation main pipe; The radial dimensions of the plurality of extraction branch pipes decrease sequentially along the gas flow direction within the extraction main pipe.

2. The injection molding die for the negative pressure fixing insert connector according to claim 1, characterized in that, The inflation manifold is an annular tube distributed circumferentially along the outer periphery of the injection nozzle.

3. The injection molding die for the negative pressure fixing insert connector according to claim 1, characterized in that, A control valve is installed at the bottom of the injection nozzle to control the injection of molten plastic into the cavity.

4. The injection molding die for the negative pressure fixing insert connector according to claim 3, characterized in that, The control valve is a throttle valve, which includes a fixed shaft fixedly installed inside the injection nozzle, a first sleeve and a second sleeve passing through the fixed shaft, a first valve plate and a second valve plate fixedly installed on the first sleeve and the second sleeve respectively, a first elastic element being provided between the fixed shaft and the first sleeve, and a second elastic element being provided between the fixed shaft and the second sleeve.

5. The injection molding die for the negative pressure fixing insert connector according to claim 4, characterized in that, The first valve plate includes an arc-shaped plate with its straight edge facing the fixed shaft, and a connecting plate for connecting to the first sleeve is provided on the straight edge. The arc-shaped edge of the arc plate matches the inner circumference of the injection nozzle. The second valve plate has the same structure as the first valve plate, and the first valve plate and the second valve plate are centrally symmetrical about the center of the length direction of the fixed shaft.

6. The injection molding die for the negative pressure fixing insert connector according to claim 4 or 5, characterized in that, Both the first elastic element and the second elastic element are coil springs.

7. The injection molding die for a negative pressure fixing insert connector according to claim 4 or 5, characterized in that, The first elastic element and the second elastic element are respectively sleeved at both ends of the fixed shaft along its length.

8. The injection molding die for the negative pressure fixing insert connector according to claim 1, characterized in that, The ejector pin extends upward from the ejector plate to the bottom of the cavity.

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