A hot runner structure to improve the quality of injection molded products

Abstract

This utility model discloses a hot runner structure for improving the quality of injection-molded products, including a module, a mold core, and multiple water channels. The module has a manifold seat with a first heating component embedded in it. A manifold channel is formed within the manifold seat. The module has a first material guiding component and multiple second material guiding components communicating with the manifold channel. A second heating component is sleeved on the outer side of each second material guiding component. The mold core has multiple molding cavities and multiple cooling seats embedded in it. A gate communicating with the molding cavity and the second material guiding component is passed through each cooling seat. A heat exchange water channel is formed within the cooling seat, and an inlet and a outlet communicating with the heat exchange water channel are also provided. Multiple air valves are provided within the module, with valve pins contacting the gate. Both the inlet and outlet are connected to the water channels. This utility model provides a hot runner structure for improving the quality of injection-molded products by rapidly reducing the temperature of the PET rubber compound through the cooling seats, thereby reducing the whitening problem of PE products.

Description

Technical Field

[0001] This utility model relates to the field of injection molding, and in particular to a hot runner structure for improving the quality of injection molded products. Background Technology

[0002] In order to improve processing efficiency, the existing injection molding process usually designs multiple molding cavities on a mold and guides the rubber material into each molding cavity through the branching of the runner. However, in order to improve the flow efficiency of the rubber material in the runner, hot runners are needed to raise the temperature of the rubber material and reduce the solidification rate of the rubber material in the hot runner, so that the rubber material can flow into each molding cavity more quickly.

[0003] When dark-colored PET material is used as the rubber compound, the hot runner and the molding cavity are in direct contact to form a heat conduction interface. This creates a local overheating zone at the gate of the molding cavity. As a result, after the PET material in the molding cavity solidifies, the PET material at the gate will cool down slowly due to the heat conduction of the hot runner. This causes a sharp increase in the temperature gradient of the PET material at that point, leading to localized whitening of the material due to crystallization, which affects the appearance of the molded product. Utility Model Content

[0004] The purpose of this invention is to provide a hot runner structure that improves the quality of injection molded products by rapidly reducing the temperature of PET material through a cooling seat, thereby reducing the whitening problem of PE products.

[0005] The technical solution adopted by the hot runner structure for improving the quality of injection molded products disclosed in this utility model is:

[0006] The system includes a module, a mold core, and multiple water channels. The module contains a flow divider seat, on which a first heating component is embedded. The flow divider seat has a flow channel. The module has a first material guiding component and multiple second material guiding components, both of which communicate with the flow channels. A second heating component is fitted around the outside of each second material guiding component. The bottom of the module has a slot. The mold core has multiple molding cavities and multiple cooling seats embedded within it. A through-hole is formed in each cooling seat. The system includes a gate connected to the molding cavity, a mold core placed in a slot, a second material guiding assembly connected to the gate, a heat exchange water channel within the cooling seat, a water inlet and a water outlet on the cooling seat, both of which are connected to the heat exchange water channel, multiple air valves within the module, a valve needle fixedly connected to the output shaft of each air valve, one end of the valve needle passing through the flow divider and the second material guiding assembly and contacting the gate, a water passage passing through the module and the mold core, and both the water inlet and the water outlet connected to the water passage.

[0007] As a preferred embodiment, the cooling seat is provided with a contact groove, the gate is located in the contact groove, the second material guiding assembly is placed in the contact groove, and the heat exchange channel surrounds the outside of the gate.

[0008] As a preferred embodiment, the cooling base is provided with a water supply channel and a return channel. The two ends of the water supply channel are connected to the water inlet and the heat exchange channel, respectively, and the two ends of the return channel are connected to the drain outlet and the heat exchange channel, respectively.

[0009] As a preferred embodiment, the cooling base has two grooves on its outer side, and the water inlet and drain outlet are located in the two grooves respectively.

[0010] As a preferred embodiment, the water passage is connected to the water inlet and outlet of the two cooling seats.

[0011] As a preferred embodiment, the water path includes a first water channel, a second water channel, and a third water channel. The first water channel is connected to the water inlet of one of the cooling seats. The second water channel is located between two cooling seats. The two ends of the second water channel are connected to the drain outlet of one cooling seat and the water inlet of the other cooling seat, respectively. The third water channel is connected to the drain outlet of the other cooling seat.

[0012] As a preferred embodiment, the first material guiding component has a first material channel running through it, which is connected to the flow channel; the second material guiding component has a second material channel running through it, which is connected to the flow channel and the gate at both ends, respectively.

[0013] As a preferred embodiment, the upper cover of the second material guiding component is provided with a heat insulation sleeve, which is located between the second material guiding component and the contact groove, and the second material channel passes through the heat insulation sleeve.

[0014] The beneficial effects of the hot runner structure disclosed in this utility model for improving the quality of injection molded finished products are:

[0015] The external injection molding mechanism injects PET material into the manifold of the manifold via the first material guide assembly. The manifold distributes the PET material evenly to each of the second material guide assemblies. The output shaft of the air valve pulls the valve needle away from the gate. The PET material in the second material guide assembly is then injected into the molding cavity through the gate of the cooling seat. The first and second heating assemblies heat the manifold and the second material guide assembly respectively, keeping the PET material warm and reducing its solidification rate. Simultaneously, the external water circulation mechanism injects low-temperature cooling water into one end of the water path. This low-temperature cooling water enters the heat exchange channel through the inlet, lowering the temperature of the cooling seat. The high-temperature cooling water then drains from the outlet and flows back into the water path. The ring mechanism recovers high-temperature cooling water from the other end of the water channel for cooling, forming a closed-loop reflux. After the PET material is injected into the molding cavity through the gate, the output shaft of the air valve pushes the valve needle to contact and block the gate, cutting off the PET material at the gate. The cooling seat rapidly cools the PET material at the gate and also separates the mold core from the second material guide assembly, preventing the high-temperature heat of the second material guide assembly from being conducted to the mold core. This allows the area near the gate and the mold core to be kept at a low temperature, and the temperature gradient difference to be small, so that the PET material in the molding cavity can be cooled down quickly. This greatly slows down the formation of crystals when the PET material solidifies, and avoids defects such as whitening or white matter on the appearance of the molded product. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of a hot runner structure for improving the quality of injection molded products according to this utility model.

[0017] Figure 2 This is a schematic diagram of a hot runner structure for improving the quality of injection molded products, based on the present invention.

[0018] Figure 3 This is a cross-sectional view of a hot runner structure module, a flow divider, and a first material guide assembly that improves the quality of injection molded finished products according to this utility model.

[0019] Figure 4 This is a cross-sectional view of a hot runner structure for improving the quality of injection molded products according to this utility model.

[0020] Figure 5 This is a schematic diagram of the installation of the second material guide component of a hot runner structure for improving the quality of injection molded products according to this utility model.

[0021] Figure 6 This is a schematic diagram of the installation of the second material guiding component and the second heating component of a hot runner structure for improving the quality of injection molded products according to this utility model.

[0022] Figure 7 This is a schematic diagram of the mold core installation for a hot runner structure that improves the quality of injection molded products according to this utility model.

[0023] Figure 8 This is a partial cross-sectional view of a hot runner structure for improving the quality of injection molded products according to this utility model.

[0024] Figure 9 This is a cross-sectional view of a cooling seat for a hot runner structure that improves the quality of injection molded products according to this utility model.

[0025] Figure 10 This is a cross-sectional view of the mold core and cooling seat of a hot runner structure for improving the quality of injection molded products according to this utility model. Detailed Implementation

[0026] The present invention will be further described and illustrated below with reference to specific embodiments and the accompanying drawings:

[0027] Please refer to Figures 1-4 .

[0028] This utility model discloses a hot runner structure for improving the quality of injection molded products, including a module 1, a mold core 5, and multiple water channels;

[0029] Module 1 is composed of an upper template 11, a lower template 12 and a mold base 13 stacked in sequence. The lower template 12 is located between the upper template 11 and the mold base 13. The upper template 11, the lower template 12 and the mold base 13 are all fixedly connected by bolts.

[0030] Furthermore, the upper template 11 has a first mounting groove through it, and the top of the lower template 12 has a receiving cavity 121. The upper template 11 covers the receiving cavity 121. The first mounting groove communicates with the receiving cavity 121. The inner wall of the receiving cavity 121 has a first wire groove, which extends out of the outer side of the lower template 12.

[0031] Furthermore, the lower template 12 is provided with a plurality of second mounting slots, which penetrate the lower template 12. In this embodiment, it is preferred that there are eight second mounting slots, and the eight second mounting slots are arranged in two rows side by side, with four second mounting slots in each row. The inner wall of the second mounting slot is provided with a second wire groove, which communicates with the receiving cavity 121.

[0032] Please refer to Figures 2-4 .

[0033] The module 1 is provided with a flow divider seat 2, which is placed in the receiving cavity 121. The top and bottom of the flow divider seat 2 are fixedly connected with heat insulation blocks, which are fixedly connected to the inner wall of the receiving cavity 121. The heat insulation blocks separate the flow divider seat 2 from the inner wall of the receiving cavity 121, preventing the flow divider seat 2 from contacting the receiving cavity 121 and reducing the heat loss of the flow divider seat 2. The flow divider seat 2 is provided with a flow divider channel 211, and a feed port is provided in the middle of the flow divider channel 211. The feed port extends out of the flow divider seat 2. The flow divider channel 211 is provided with eight discharge ports, which are respectively close to eight second mounting slots.

[0034] Furthermore, a first heating component 22 is embedded in the distribution seat 2. The first heating component 22 includes eight first heating wires 221, which are respectively embedded in the top and bottom of the distribution seat 2. An external power source is electrically connected to the first heating wires 221 through a wire through the first wire groove into the receiving cavity 121. The external power source provides electrical energy to the first heating wires 221, which generate heat to heat the distribution seat 2, so that the distribution seat 2 has the effect of keeping the PET material in the distribution channel 211 warm.

[0035] The module 1 is provided with a first material guiding component 3, which is placed in a first mounting groove, and a first material channel 311 is passed through the first material guiding component 3;

[0036] Furthermore, the first material guiding assembly 3 includes a first nozzle and a limiting ring. The first nozzle is placed in the first mounting groove. One end of the first nozzle is fixedly connected to the top of the diverter seat 2. The limiting ring is fixedly connected to the top of the upper template 11. The limiting ring engages with the other end of the first nozzle. The limiting ring constrains the first nozzle within the first mounting groove. The first material channel 311 passes through the limiting ring and the first nozzle. One end of the first material channel 311 is connected to the feed inlet of the diverter channel 211.

[0037] Please refer to Figures 4-6 .

[0038] The diversion seat 2 is provided with a plurality of second material guiding components 4. In this embodiment, it is preferred that there are eight second material guiding components 4, and the eight second material guiding components 4 correspond to eight second mounting slots. The second material guiding components 4 are placed in the second mounting slots.

[0039] Furthermore, the second material guiding assembly 4 includes a second nozzle 42, a positioning sleeve 43, and a nozzle core 44; a limiting groove is formed at one end of the second nozzle 42, and the positioning sleeve 43 and the nozzle core 44 are both placed in the limiting groove, and the nozzle core 44 is constrained in the limiting groove; a second material channel 411 passes through the second material guiding assembly 4, and the second material channel 411 passes through the second nozzle 42, the positioning sleeve 43, and the nozzle core 44 in sequence, and multiple positioning posts are extended from the inner wall of the positioning sleeve 43 at intervals;

[0040] Furthermore, the other end of the second nozzle 42 is fixedly connected to the bottom of the diversion seat 2, and the second material channel 411 is connected to the outlet of the diversion channel 211.

[0041] A second heating assembly 45 is sleeved on the outside of the second material guiding assembly 4. The second heating assembly 45 includes a heat conducting pipe 451. The heat conducting pipe 451 is sleeved on the outside of the second nozzle 42. A second electric heating wire 452 is embedded in the outside of the heat conducting pipe 451. The second electric heating wire 452 is wound around the outside of the heat conducting pipe 451. An external power supply is electrically connected to the second electric heating wire 452 through a wire passing through the first wire groove, the receiving cavity 121 and the second wire groove into the second mounting groove. The external power supply provides electrical energy to the second electric heating wire 452, so that the second electric heating wire 452 generates heat to heat the second material guiding assembly 4, so that the second material guiding assembly 4 has the effect of keeping the PET material in the second material channel 411 warm.

[0042] Furthermore, a thermocouple is embedded in the heat pipe 451. The thermocouple is used to monitor the operating temperature of the second material guiding assembly 4. The temperature of the PET material in the second material channel 411 is adjusted by adjusting the temperature generated by the second heating wire 452.

[0043] Please refer to Figure 1 , Figure 4 and Figures 7-10 .

[0044] The bottom of module 1 has a slot 131, which is located at the bottom of mold base 13. The second mounting slot passes through mold base 13 and communicates with slot 131. Mold core 5 is placed in slot 131. The bottom of mold core 5 has multiple molding cavities. In this embodiment, it is preferred that there are eight molding cavities, which correspond to eight second material guiding components 4. The top of mold core 5 has multiple cooling seats 6. In this embodiment, it is preferred that there are eight cooling seats 6, which correspond to eight molding cavities. The diameter of the cooling seats 6 is larger than the second mounting slot, which increases the distance between the mold core 5 and the second material guiding components 4, thereby reducing the high temperature heat conduction of the second material guiding components 4 to the mold core 5.

[0045] Furthermore, a contact groove 61 is provided on the top of the cooling seat 6, and a gate is passed through the cooling seat 6. The gate is connected to the molding cavity and is located in the contact groove 61.

[0046] Furthermore, the second material guide assembly 4 is placed in the contact groove 61, and the upper cover of the second material guide assembly 4 is provided with a heat insulation sleeve 411. The heat insulation sleeve 411 covers the end face of one end of the nozzle core 44, and the second material channel 411 passes through the heat insulation sleeve 411. The heat insulation sleeve 411 is located between the nozzle core 44 of the second material guide assembly 4 and the contact groove 61. The second material channel 411 of the second material guide assembly 4 is connected to the gate. The heat insulation sleeve 411 separates the cooling seat 6 from the nozzle core 44, reducing the high temperature heat conduction of the nozzle core 44 to the cooling seat 6.

[0047] The cooling base 6 is provided with a heat exchange water channel 62, a water inlet 63, a water outlet 64, a water supply channel 631, and a return channel 641. The heat exchange water channel 62 surrounds the outside of the gate, thereby improving the efficiency of the heat exchange water channel 62 in cooling the area of ​​the cooling base 6 located at the gate.

[0048] Furthermore, the water supply channel 631 and the return channel 641 are located on both sides of the heat exchange channel 62, which can further improve the efficiency of cooling water in cooling the cooling base 6; the two ends of the water supply channel 631 are connected to the water inlet 63 and the heat exchange channel 62 respectively, and the two ends of the return channel 641 are connected to the drain outlet 64 and the heat exchange channel 62 respectively.

[0049] Furthermore, two grooves 65 are provided on the outer side of the cooling seat 6, with the water inlet 63 and the drain outlet 64 located in the two grooves 65 respectively. Due to the design of the cooling seat 6 being embedded in the mold core 5, the two grooves 65 form two independent chambers, allowing cooling water to enter the two grooves 65 and exchange heat with the outer side of the cooling seat 6, further improving the efficiency of the cooling water in cooling the cooling seat 6.

[0050] The module 1 is equipped with multiple air valves 7. In this embodiment, there are eight air valves 7, which correspond to eight cooling seats 6. An external compressor is connected to the air valves 7 and controls their operation. A valve needle 71 is fixedly connected to the output shaft of the air valve 7. One end of the valve needle 71 passes through the outlet of the flow divider 2 and the second material channel 411 of the second material guide assembly 4 and touches the gate. The positioning post of the positioning sleeve 43 touches the outside of the valve needle 71. The positioning post restricts the valve needle 71 to move only axially back and forth, so that the valve needle 71 can accurately touch the gate.

[0051] By controlling the opening and closing of the air valve 7, the valve needle 71 is pulled away from or touches the gate, thus realizing the injection of the mold core 5.

[0052] In this embodiment, four water channels are preferred. The water channels run through the module 1 and the core 5, and are connected to the water inlet 63 and the water outlet 64 of the two cooling seats 6.

[0053] Furthermore, the water passage includes a first water channel 141, a second water channel 142, and a third water channel 143; the first water channel 141 extends into the mold base 13 and the mold core 5, and is connected to the water inlet 63 of one of the cooling seats 6; the second water channel 142 is formed inside the mold core 5, and is located between the two cooling seats 6, with its two ends connected to the drain outlet 64 of one cooling seat 6 and the water inlet 63 of the other cooling seat 6, respectively; the third water channel 143 extends into the mold base 13 and the mold core 5, and is connected to the drain outlet 64 of the other cooling seat 6.

[0054] The water supply port of the external water circulation mechanism is connected to the first water channel 141, and the water return port of the external water circulation mechanism is connected to the third water channel 143. The external water circulation mechanism simultaneously injects low-temperature cooling water into the first water channel 141. The low-temperature cooling water in the first water channel 141 enters the heat exchange water channel 62 through the water inlet 63 of one of the cooling seats 6. After lowering the temperature of one of the cooling seats 6, the room temperature cooling water is discharged from the drain port 64 and flows back into the second water channel 142. The room temperature cooling water in the second water channel 142 enters the heat exchange water channel 62 through the water inlet 63 of the other cooling seat 6. After lowering the temperature of the other cooling seat 6, the high temperature cooling water is discharged from the drain port 64 and flows back into the third water channel 143. The external water circulation mechanism recovers the high temperature cooling water from the third water channel 143 for cooling, forming a closed loop reflux.

[0055] Please refer to Figures 1-10 .

[0056] The external power source is the first heating wire 221 and the second heating wire 452. Through electrical energy, the flow divider 2 and the second material guide assembly 4 are heated to a specified temperature, thereby slowing down the solidification speed of the PET material in the flow divider 211 and the material channel 411 and reducing the flow resistance of the PET material.

[0057] After preheating is completed, PET material is injected into the distribution channel 211 of the distribution seat 2 through the first material channel 311 of the first material guide component 3 via the external injection mechanism. The distribution channel 211 distributes the PET material evenly to each second material guide component 4.

[0058] When injection molding begins, the output shaft of the air valve 7 pulls the valve needle 71 away from the gate, opening the connection between the second material guide assembly 4 and the molding cavity through the gate. The PET material in the second material guide assembly 4 is injected into the molding cavity through the gate of the cooling seat 6. At the same time, the external water circulation mechanism injects low-temperature cooling water into the water circuit to cool the cooling seat 6. When the PET material completely fills the molding cavity, the output shaft of the air valve 7 pushes the valve needle 71 to touch the gate, and the valve needle 71 cuts off the PET material at the gate, making it easier to demold the molded product 8.

[0059] While the cooling seat 6 rapidly cools down the PET material at the gate, it also separates the mold core 5 from the second material guide assembly 4, preventing the high-temperature heat from the second material guide assembly 4 from being conducted to the mold core 5. This allows the area near the gate and the mold core 5 to be kept at a low temperature with a small temperature gradient, enabling the PET material in the molding cavity to cool down rapidly. This significantly slows down the formation of crystals during the solidification of the PET material, preventing defects such as whitening or white matter from appearing on the appearance of the molded product 8.

[0060] This invention provides a hot runner structure to improve the quality of injection-molded products. An external injection molding mechanism injects PET material into the manifold of the manifold via a first material guide assembly. The manifold evenly distributes the PET material to each second material guide assembly. The output shaft of the air valve pulls the valve needle away from the gate. The PET material in the second material guide assembly is then injected into the molding cavity through the gate of the cooling seat. A first heating assembly and a second heating assembly heat the manifold and the second material guide assembly respectively, keeping the PET material warm and reducing its solidification rate. Simultaneously, an external water circulation mechanism injects low-temperature cooling water into one end of the water path. This low-temperature cooling water enters the heat exchange water channel through the inlet, lowering the temperature of the cooling seat. High-temperature cooling water then drains from the outlet. The PET material flows back into the water channel, and the external water circulation mechanism recovers high-temperature cooling water from the other end of the water channel for cooling, forming a closed-loop reflux. After the PET material is injected into the molding cavity through the gate, the output shaft of the air valve pushes the valve needle to contact and block the gate, cutting off the PET material at the gate. The cooling seat rapidly cools the PET material at the gate and also separates the mold core from the second material guide assembly, preventing the high-temperature heat of the second material guide assembly from being conducted to the mold core. This allows the area near the gate and the mold core to be kept at a low temperature, and the temperature gradient difference to be small, so that the PET material in the molding cavity can be cooled down quickly. This greatly slows down the formation of crystals when the PET material solidifies, and avoids defects such as whitening or white matter on the appearance of the molded product.

[0061] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit the scope of protection of this utility model. Although this utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of this utility model without departing from the essence and scope of the technical solutions of this utility model.

Claims

1. A hot runner structure for improving the quality of injection-molded finished products, characterized in that, include: The module includes a flow divider seat, a first heating component embedded in the flow divider seat, a flow divider channel opened in the flow divider seat, a first material guiding component and multiple second material guiding components on the module, both the first and second material guiding components being connected to the flow divider channel, a second heating component being sleeved on the outside of the second material guiding component, and a slot being opened at the bottom of the module. The mold core has multiple molding cavities and multiple cooling seats embedded in it. A gate passes through the cooling seat and communicates with the molding cavity. The mold core is placed in a slot. The second material guiding assembly communicates with the gate. A heat exchange water channel is provided in the cooling seat. A water inlet and a water outlet are provided on the cooling seat and are both connected to the heat exchange water channel. The module is equipped with multiple air valves, and the output shaft of each air valve is fixedly connected to a valve needle. One end of the valve needle passes through the flow divider and the second material guide assembly in sequence and contacts the gate. Multiple water channels run through the module and the core, and the water inlet and outlet are connected to the water channels.

2. The hot runner structure for improving the quality of injection molded products as described in claim 1, characterized in that, The cooling seat has a contact groove, the gate is located in the contact groove, the second material guiding assembly is placed in the contact groove, and the heat exchange channel surrounds the outside of the gate.

3. The hot runner structure for improving the quality of injection molded products as described in claim 2, characterized in that, The cooling base is provided with a water supply channel and a return channel. The two ends of the water supply channel are connected to the water inlet and the heat exchange channel, respectively. The two ends of the return channel are connected to the drain outlet and the heat exchange channel, respectively.

4. The hot runner structure for improving the quality of injection molded products as described in claim 3, characterized in that, The cooling base has two grooves on its outer side, and the water inlet and drain are located in the two grooves respectively.

5. A hot runner structure for improving the quality of injection-molded finished products as described in any one of claims 2 or 4, characterized in that, The water passage is connected to the inlet and outlet of the two cooling seats.

6. The hot runner structure for improving the quality of injection molded products as described in claim 5, characterized in that, The water system includes a first water channel, a second water channel, and a third water channel. The first water channel is connected to the inlet of one of the cooling seats. The second water channel is located between two cooling seats. The two ends of the second water channel are connected to the drain of one cooling seat and the inlet of the other cooling seat, respectively. The third water channel is connected to the drain of the other cooling seat.

7. A hot runner structure for improving the quality of injection-molded finished products as described in claim 6, characterized in that, The first material guiding component has a first material channel that is connected to the flow channel. The second material guiding component has a second material channel that is connected to the flow channel and the gate at both ends.

8. A hot runner structure for improving the quality of injection-molded finished products as described in claim 7, characterized in that, The second material guiding component is covered with a heat insulation sleeve, which is located between the second material guiding component and the contact groove, and the second material channel passes through the heat insulation sleeve.

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