Mobile phone plastic middle frame mold capable of reducing weight of glue inlet of front mold

Abstract

The invention relates to the technical field of mobile phone middle frame molds, and particularly discloses a mobile phone plastic middle frame mold capable of reducing the weight of a front mold glue inlet, which comprises a front mold bottom plate, a heat flow plate arranged on the front mold bottom plate, a pipeline arranged on the heat flow plate and a front mold core arranged on the pipeline, a hot runner is arranged on the pipeline and used for conveying and heating injection molding materials, a sub-runner and a sprue are arranged on the front mold core, one side of the front mold core protrudes outwards to form a mold core, the mold core is matched with a mold cavity of the rear mold core to form an injection molding space, the sprue is communicated with the sub-runner and the injection molding space, one end of the hot runner is communicated with the sub-runner, and the other end of the hot runner is communicated with a nozzle of an injection molding machine. The hot flow plate provides heat for the injection molding material in the hot runner; the pore size of the end part, close to the sub-runner, in the hot runner is continuously transitionally changed, the sub-runner is provided with a plurality of sub-runners, the sub-runners are distributed around the central axis of the pipeline from the communication part of the hot runner and the sub-runner to form a spoke-shaped structure, and the sprues are communicated with the corresponding sub-runners.

Description

Technical Field

[0001] The invention relates to the technical field of mobile phone middle frame molds, and in particular discloses a mobile phone plastic middle frame mold capable of reducing the weight of a front mold glue inlet. Background Art

[0002] In the production process of mobile phone plastic middle frames, traditional molds have many problems. For example, the unreasonable design of the hot runner leads to poor flow of the injection material, excessive local pressure, and great pressure on the glue inlet of the front mold; the single structure of the diverter cannot evenly distribute the injection material, which makes the glue inlet of the front mold heavy; the gate structure is not good, which cannot meet the conveying requirements of injection materials with different flow rates, affecting the stability of the glue inlet of the front mold; the lack of precise temperature control of the hot runner plate causes the instability of the injection material flow parameters, which increases the burden on the glue inlet of the front mold; the stripping insert and the front mold core are not tightly matched, and the design of the sprue hook is unreasonable, which easily causes abnormal material flow and increases the pressure of the glue inlet of the front mold; the unreasonable design of the groove of the front mold core, the poor heat dissipation of the front mold bottom plate, and the unstable connection of the gate sleeve all affect the stability and efficiency of the injection molding process, making the weight of the glue inlet of the front mold heavy, affecting the service life of the mold and product quality. Summary of the invention

[0003] In order to overcome the shortcomings and deficiencies in the prior art, an object of the present invention is to provide a mobile phone plastic middle frame mold that reduces the weight of the glue inlet of the front mold.

[0004] To achieve the above-mentioned purpose, the present invention provides a mobile phone plastic middle frame mold that reduces the weight of the front mold glue inlet, comprising a front mold bottom plate, a hot flow plate arranged on the front mold bottom plate, a pipeline arranged on the hot flow plate, and a front mold core arranged on the pipeline, a hot runner is arranged on the pipeline for conveying and heating the injection molding material, a diverter channel and a gate are arranged on the front mold core, one side of the front mold core protrudes outward to form a mold core and cooperates with the mold cavity of the rear mold core to form an injection molding space, the gate is connected with the diverter channel and the injection molding space, one end of the hot runner is connected with the diverter channel, and the other end is connected with the nozzle of the injection molding machine, the hot flow plate provides heat for the injection molding material in the hot runner; the aperture size of the end near the diverter channel inside the hot runner continuously transitions, the diverter channel has a plurality of diverter channels, and the plurality of diverter channels are distributed around the central axis of the pipeline from the hot runner and the connection point of the diverter channel to form a spoke-like structure, the gate is connected with the corresponding diverter channel, and the hot runner, the diverter channel and the gate together constitute a casting system.

[0005] The unique hot runner design has a continuous transition change in the size of the end aperture near the runner, which makes the injection material flow more smoothly and reduces the flow resistance, thereby reducing the pressure requirement for the front mold glue inlet and reducing the weight of the front mold glue inlet. The runner has multiple branch paths and is distributed in a spoke-like structure. This design can evenly distribute the injection material and avoid excessive local pressure, thereby reducing the burden on the front mold glue inlet and achieving the purpose of reducing the weight of the front mold glue inlet. The pouring system composed of the hot runner, runner and gate reduces unnecessary material accumulation by optimizing the structure while ensuring the injection effect, further reducing the weight of the front mold glue inlet.

[0006] Furthermore, the pipeline is arranged as a multi-layer tube structure, the hot runner is arranged in the innermost layer of the multi-layer tube structure, and a pore structure is provided between the multi-layer tube structures for thermal insulation of the injection molding material in the hot runner. The hot runner has a first flat portion, a first transition portion, a second flat portion, a second transition portion, a third flat portion and a third transition portion arranged in sequence along the length direction of the pipeline, and the flat portions and the transition portions are arranged at intervals. The aperture sizes of the flow holes where the first, second and third flat portions are located are all unchanged, the aperture sizes of the flow holes where the first transition portion and the second transition portion are located are uniformly reduced from large, and the aperture sizes of the flow holes where the third transition portion is located are uniformly increased from small, the aperture changes of the first transition portion and the third transition portion are both linear, and the aperture change of the second transition portion is arc-shaped.

[0007] The hot runner is set in the innermost layer of the multi-layer tube structure, and the pore structure in the middle can effectively block the heat from being transferred to the outside. During the injection molding process, the hot runner needs to keep the injection material at a suitable melting temperature. Through this structural design, the heat loss is greatly reduced. The thermal insulation effect of the pore structure helps to maintain the stability of the hot runner temperature. Because it can buffer the impact of external temperature changes on the hot runner, the temperature fluctuation of the injection material in the hot runner is reduced. Stable temperature is crucial to the quality of injection molded products. It can ensure that the injection material has uniform fluidity throughout the injection molding process and avoid product defects caused by temperature fluctuations, such as surface flaws, internal bubbles or dimensional deviations. The unique segmented structure of the hot runner includes a first gentle portion, a first transition portion, a second gentle portion, a second transition portion, a third gentle portion and a third transition portion arranged in sequence. This design makes the flow of injection materials in the hot runner more orderly and stable. The first transition part and the third transition part have a linear aperture change, and the second transition part has an arc-shaped aperture change. This diversified transition method can better control the flow rate and pressure of the injection material, reduce the impact on the front mold glue inlet, and thus reduce the weight of the front mold glue inlet. The flat part and the transition part are arranged at intervals, and the aperture size of the flow hole where the flat part is located remains unchanged, ensuring stability during the injection molding process. The aperture change design of the transition part can adjust the flow state of the material according to the injection molding requirements at different stages, avoiding the situation of excessive local pressure, and effectively reducing the weight of the front mold glue inlet.

[0008] Furthermore, the shunt path has a first branch, a second branch and a third branch which are arranged on the front mold core and are connected in sequence, the first branch corresponds to the shunt path one by one, and multiple first branches are arranged in the same plane, the second branches correspond to the first branches one by one, the length direction of any second branch is perpendicular to the length direction of the corresponding first branch, the third branch is distributed around the central axis of the second branch, and the third branch is connected to the gate; the connecting point between any first branch and the second branch and / or the connecting point between any second branch and the third branch is provided with a semicircular protrusion for slowing down the impact of the molten injection material on the runner.

[0009] The unique design of the shunt path includes a first branch, a second branch and a third branch connected in sequence, so that the injection molding material can flow to the gate in an orderly manner. The coplanar arrangement of multiple first branches and the vertical arrangement of the second branch and the first branch ensure the rationality and stability of the material flow. The third branch is arranged around and connected to the gate, which further optimizes the injection molding path. The structural design of this shunt path reduces the turbulence and pressure concentration of the material during the flow process, thereby reducing the pressure on the front mold glue inlet and achieving the effect of reducing the weight of the front mold glue inlet. A semicircular protrusion is provided at the connection point between the first branch and the second branch and / or the connection point between the second branch and the third branch, which can effectively reduce the impact of the molten injection molding material on the runner. This design reduces the impact force of the material flow, reduces the impact on the front mold glue inlet, and thus reduces the weight of the front mold glue inlet.

[0010] Furthermore, the gate has a first feed port with an arc fan-shaped structure arranged on the mold core and a second feed port with a pin-point structure. The second feed port is formed by the end of a portion of the second branch. The first feed port is connected to the third branch and the two correspond one to one. The first feed port is used to convey a large flow of injection molding material, and the second feed port is used to convey a small flow of injection molding material.

[0011] The unique design of the gate includes a first feed port with a curved fan-shaped structure and a second feed port with a pin-point structure, which can deliver injection molding materials of different flow rates according to different injection molding requirements. The first feed port is used to deliver large-flow materials to ensure injection molding efficiency; the second feed port is used to deliver small-flow materials to improve injection molding accuracy. This reasonable gate design makes the injection molding process more stable, reduces the pressure fluctuation on the front mold glue inlet, and thus reduces the weight of the front mold glue inlet. The second feed port is formed by the end of part of the second branch, and cooperates with the structure of the shunt path to make the flow of injection molding materials smoother. At the same time, this design avoids the accumulation and blockage of materials at the gate, reduces the burden on the front mold glue inlet, and achieves the purpose of reducing the weight of the front mold glue inlet.

[0012] Furthermore, a heavy-duty connector is provided on the hot runner plate to connect with an external temperature control box, and the temperature control box controls the heating parameters of the hot runner plate to adjust the flow parameters of the injection molding material in the hot runner so that the injection molding material flows smoothly in the hot runner.

[0013] A heavy-duty connector is set on the hot runner to connect to the external temperature control box. The temperature control box can accurately control the heating parameters of the hot runner, and then adjust the flow parameters of the injection material in the hot runner. In this way, the injection material can flow smoothly in the hot runner, avoiding excessive pressure on the front mold glue inlet due to unstable material flow, thereby reducing the weight of the front mold glue inlet. Accurate temperature control and flow parameter adjustment can improve the quality and efficiency of injection molding, while also reducing the risk of damage to the front mold glue inlet due to abnormal material flow and extending the service life of the mold.

[0014] Furthermore, a stripping insert is provided on the pipeline, and the stripping insert is assembled and matched with the front mold core. One side of the stripping insert protrudes outward to form a positioning boss that cooperates with the front mold core, and a space-avoiding step is formed between the positioning boss and the stripping insert. The boss surface of the positioning boss is provided with a through hole along the thickness direction of the stripping insert to cooperate with the diversion path. The diversion path is formed in an L-shape, and a sprue hook is provided in the through hole. One end of the sprue hook protrudes into the diversion channel through the intersection of the L-shaped flow channel to form a hook shape, and the other end is detachably connected to the stripping insert.

[0015] The stripping insert is arranged on the pipeline, which is assembled with the front mold core to ensure the stability of the mold structure. The positioning boss on one side of the stripping insert is closely matched with the front mold core, and the through hole on the boss surface is matched with the diversion path, making the injection process more precise. The diversion path is L-shaped, and with the sprue hook, it can effectively control the flow and demoulding of the injection material. An air avoidance step is formed between the positioning boss and the stripping insert, which provides operating space when installing and removing the stripping insert. This makes the installation process more convenient and can accurately assemble the stripping insert with the front mold core. The existence of the air avoidance step can avoid interference between the positioning boss and other components during the working process of the mold. This precise structural design reduces the uncertainty of the material in the flow process, reduces the pressure on the glue inlet of the front mold, and thus reduces the weight of the glue inlet of the front mold. One end of the sprue hook protrudes into the diversion channel in a hook shape, and the other end is detachably connected to the stripping insert, which facilitates the maintenance and cleaning of the mold. At the same time, this design also helps to improve the efficiency and quality of injection molding, reduce the adverse effects on the glue inlet of the front mold caused by the gate problem, and achieve the purpose of reducing the weight of the glue inlet of the front mold.

[0016] Furthermore, the stripping insert and the front mold core are both provided with cooling water channels, which are arranged in a tic-tac-toe pattern and surround the central axis of the pipeline. The layout of the cooling water channels is matched with the size of the mold core.

[0017] The stripping insert and the front mold core are provided with cooling water channels in a tic-tac-toe pattern and around the central axis of the pipeline, which can effectively cool the mold and improve the injection efficiency. This layout is matched with the size of the mold core, making the cooling more uniform and avoiding local overheating or overcooling. Uniform cooling can reduce the internal stress caused by uneven temperature, thereby reducing the impact on the front mold glue inlet and reducing the weight of the front mold glue inlet. Reasonable cooling water channel layout can also increase the service life of the mold, reduce mold deformation caused by uneven thermal expansion and contraction, further ensure the stability of the injection process, and provide strong support for reducing the weight of the front mold glue inlet.

[0018] Furthermore, a heating plate is provided on the hot flow plate, and a heater is embedded in the heating plate for heating the hot runner. The heater is electrically connected to the temperature control box for controlling the heating parameters of the heater; the side of the hot flow plate away from the hot runner is recessed inward to form an accommodating groove for accommodating the heating plate, and the accommodating groove extends along the length and / or width direction of the hot flow plate to communicate with the outside to form a heat dissipation groove, and both sides of the length direction of the side of the hot flow plate away from the hot runner are recessed inward to form a step structure.

[0019] A heating plate and a heater embedded therein are arranged on the hot runner to provide a stable heating source for the hot runner. The heater is electrically connected to the temperature control box, and the heating parameters can be accurately controlled to ensure that the injection molding material maintains appropriate fluidity in the hot runner. This precise temperature control reduces the instability of material flow and reduces the pressure on the glue inlet of the front mold, thereby reducing the weight of the glue inlet of the front mold. The accommodating groove on the hot runner is used to accommodate the heating plate, and extends along the length and / or width direction of the hot runner to form a heat dissipation groove, which can effectively dissipate the heat generated by the heater and prevent local overheating of the hot runner. Good heat dissipation performance ensures the uniformity of the hot runner temperature, avoids the influence of uneven temperature on the material flow, and thus reduces the burden on the glue inlet of the front mold, achieving the purpose of reducing the weight of the glue inlet of the front mold. The hot runner forms a step structure on both sides of the length direction away from the hot runner side, which increases the structural stability of the hot runner, and also helps to evenly distribute and dissipate heat, further improves the working stability of the mold, and provides a reliable guarantee for reducing the weight of the glue inlet of the front mold.

[0020] Furthermore, one side of the front mold core is recessed inward to form a first groove, and the side of the front mold core away from the first groove is recessed inward to form a second groove for cooperating with the rear mold core. The number of the second grooves is set to multiple, and the multiple second grooves are distributed around the mold core.

[0021] One side of the front mold core is recessed inward to form a first groove, and the other side forms multiple second grooves for matching with the rear mold core. This design optimizes the structure of the mold. Multiple second grooves are distributed around the mold core, making the front mold core and the rear mold core match more tightly and stably. Stable matching reduces pressure fluctuations during the injection molding process, thereby reducing the impact on the front mold glue inlet and achieving the purpose of reducing the weight of the front mold glue inlet. Reasonable groove design can also optimize the flow path of the injection material to a certain extent, avoid material accumulation and blockage in the mold, reduce the burden on the front mold glue inlet, and further contribute to reducing the weight of the front mold glue inlet.

[0022] Furthermore, a heat dissipation pad is installed on the side of the front mold bottom plate away from the hot runner, and a gate sleeve is screwed on it for connecting with the nozzle of the injection molding machine. A positioning ring is installed on the heat dissipation pad for positioning connection with the nozzle of the injection molding machine, and the gate sleeve is connected to the hot runner.

[0023] Installing a heat dissipation pad on the side of the front mold bottom plate away from the hot runner can effectively dissipate the heat generated during the injection molding process, reduce the temperature of the mold, and increase the service life of the mold. The screw-connected gate sleeve is connected to the nozzle of the injection molding machine to ensure the smooth delivery of the injection molding material. The positioning ring installed on the heat dissipation pad is used for positioning and connecting with the nozzle of the injection molding machine to ensure the accuracy and stability of the injection molding. This reasonable structural design reduces the adverse effects on the front mold glue inlet caused by excessive temperature or unstable connection, thereby reducing the weight of the front mold glue inlet. The gate sleeve is connected to the hot runner, so that the injection molding material can flow into the mold quickly and evenly. Good connectivity reduces the resistance and pressure loss of the material during the flow process, reduces the pressure requirement for the front mold glue inlet, and thus achieves the purpose of reducing the weight of the front mold glue inlet.

[0024] The beneficial effects of the present invention are as follows: through the unique aperture change design of the hot runner, the spoke-shaped structure and multiple branch path design of the runner, the special structure of the gate, the connection between the hot runner plate and the temperature control box to achieve precise temperature control, the cooperation of the stripping insert and the front mold core and the sprue hook design, the groove design of the front mold core, the heat dissipation pad of the front mold bottom plate and the gate sleeve and other structural designs, the injection molding material can flow more smoothly and stably in the mold, reducing the flow resistance, impact force and pressure fluctuation, avoiding material accumulation and blockage, and optimizing the temperature control and mold structure stability, thereby effectively reducing the weight of the front mold glue inlet, improving the injection molding efficiency and quality, and extending the service life of the mold. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a first overall structural schematic diagram of a mobile phone plastic middle frame mold for reducing the weight of a front mold glue inlet of the present invention;

[0026] Figure 2 It is a second overall structural schematic diagram of the present invention;

[0027] Figure 3 It is a schematic diagram of the local structure of the present invention;

[0028] Figure 4 It is an exploded view of the local structure of the present invention;

[0029] Figure 5 It is a structural schematic diagram and a structural explosion diagram of the pipeline of the present invention;

[0030] Figure 6 It is a structural cross-sectional view of the pipe of the present invention;

[0031] Figure 7 It is a structural cross-sectional view of the hot nozzle of the present invention;

[0032] Figure 8 It is a partial structural schematic diagram of the front mold core of the present invention;

[0033] Fig. 9 It is a schematic structural diagram of the runner and gate of the present invention;

[0034] Fig.10 It is a schematic diagram of the structure of the heat flow plate of the present invention;

[0035] Fig.11 It is a schematic diagram of the local structure of the heat flux plate of the present invention;

[0036] Fig.12 It is a schematic structural diagram of the stripping insert of the present invention.

[0037] The reference numerals include: 1, front mold base plate; 11, gate sleeve; 2, hot flow plate; 21, heavy-duty connector; 22, heating plate; 23, heater; 24, accommodating groove; 25, heat dissipation groove; 3, pipeline; 31, hot runner; 311, first flat portion; 312, first transition portion; 313, second flat portion; 314, second transition portion; 315, third flat portion; 316, third transition portion; 32, outer tube; 33, first inner tube; 34, second inner tube; 35, hot nozzle; 36, hot nozzle insert; 37. Insulating air gap layer; 4. Front mold core; 41. Diverter; 411. Diverter path; 4111. First branch; 4112. Second branch; 4113. Third branch; 4114. Protrusion; 42. Gate; 421. First feed port; 422. Second feed port; 43. Mold core; 44. First groove; 45. Second groove; 5. Stripping insert; 51. Positioning boss; 52. Through hole; 53. Inlet hook; 54. Air-avoiding step; 6. Cooling water channel; 7. Heat dissipation pad; 71. Positioning ring. DETAILED DESCRIPTION

[0038] In order to facilitate the understanding of those skilled in the art, the present invention is further described below in conjunction with embodiments and drawings. The contents mentioned in the implementation modes are not intended to limit the present invention.

[0039] See also Figures 1 to 12 As shown, a mobile phone plastic middle frame mold for reducing the weight of the front mold glue inlet of the present invention comprises a front mold bottom plate 1, a hot flow plate 2 arranged on the front mold bottom plate 1, a pipe 3 arranged on the hot flow plate 2, and a front mold core 4 arranged on the pipe 3, a hot runner 31 is arranged on the pipe 3 for conveying and heating the injection molding material, a branch channel 41 and a gate 42 are arranged on the front mold core 4, one side of the front mold core 4 protrudes outward to form a mold core 43 and cooperates with the mold cavity of the rear mold core to form an injection molding space, the gate 42 is connected with the branch channel 41 and the injection molding space, and the hot runner 31 is arranged on the pipe 3 for conveying and heating the injection molding material. One end of 31 is connected to the branch channel 41, and the other end is connected to the nozzle of the injection molding machine. The hot runner plate 2 provides heat for the injection molding material in the hot runner 31. The aperture size of the end of the hot runner 31 near the branch channel 41 changes continuously and transitionally. The branch channel 41 has a plurality of branch paths 411. The plurality of branch paths 411 are distributed around the central axis of the pipeline 3 from the connection between the hot runner 31 and the branch channel 41 to form a spoke-like structure. The gate 42 is connected to the corresponding branch path 411. The hot runner 31, the branch channel 41 and the gate 42 together constitute a casting system.

[0040] In actual use, the front mold base plate 1 can be made of high-strength steel to provide stable support. The hot runner 2 is fixed to the front mold base plate 1 by bolts to ensure the firmness of the connection. The pipe 3 can be made of metal and has good thermal conductivity. The front mold core 4 is precisely installed on the pipe 3 to ensure accurate positioning. The hot runner 31 is used for conveying and heating the injection molding material. Its internal structure is reasonably designed and can efficiently convey the injection molding material to the diverter 41 and the gate 42. The design of the diverter 41 and the gate 42 allows the injection molding material to flow evenly into the injection space, ensuring the quality of the plastic middle frame of the mobile phone. The hot runner 2 provides heat for the injection molding material in the hot runner 31 to ensure that the injection molding material flows at a suitable temperature.

[0041] Specifically, the pipeline 3 is configured as a multi-layer tube structure, and the hot runner 31 is configured in the innermost layer of the multi-layer tube structure. A pore structure is provided between the multi-layer tube structures for heat insulation of the injection molding material in the hot runner 31. The hot runner 31 has a first flat portion 311, a first transition portion 312, a second flat portion 313, a second transition portion 314, a third flat portion 315 and a third transition portion 316 which are sequentially arranged and distributed along the length direction of the pipeline 3. The flat portions and the transition portions are arranged at intervals. The aperture sizes of the flow holes where the first, second and third flat portions 315 are located are all unchanged. The aperture sizes of the flow holes where the first transition portion 312 and the second transition portion 314 are located are uniformly reduced from large, and the aperture sizes of the flow holes where the third transition portion 316 is located are uniformly increased from small. The aperture changes of the first transition portion 312 and the third transition portion 316 are both linear, and the aperture change of the second transition portion 314 is arc-shaped.

[0042] In actual use, the hot runner 31 is arranged in the innermost layer of the multi-layer tube structure, and the pore structure in the middle can effectively block the heat from being transferred to the outside. During the injection molding process, the hot runner 31 needs to keep the injection molding material at a suitable melting temperature. Through this structural design, the heat loss is greatly reduced. The heat insulation effect of the pore structure helps to maintain the temperature stability of the hot runner 31. Because it can buffer the impact of external temperature changes on the hot runner 31, the temperature fluctuation of the injection molding material in the hot runner 31 is reduced. Stable temperature is crucial to the quality of injection molded products. It can ensure that the injection molding material has uniform fluidity throughout the injection molding process and avoid product defects caused by temperature fluctuations, such as surface flaws, internal bubbles or dimensional deviations.

[0043] In actual use, first, connect the nozzle of the injection molding machine to the hot runner 31, and inject the molten plastic material into the hot runner 31. After the material enters the first gentle section 311, the material can quickly flow into the hot runner 31 due to the large aperture. As the material passes through the first transition section 312, the aperture gradually becomes smaller, and the material flow rate gradually decreases, avoiding the injection and turbulence that may be caused by too fast a flow rate. Then, the material enters the second gentle section 313, and the flow rate remains relatively stable. In the second transition section 314, the arc-shaped aperture change allows the flow rate of the material to be further adjusted smoothly, ensuring that the material flows more smoothly. Then, the material enters the third gentle section 315, providing a stable foundation for subsequent flow. Finally, through the third transition section 316, the aperture changes from small to large evenly, pushing the material smoothly to the branch channel 41.

[0044] In this embodiment, the pipeline 3 has an outer tube 32, a first inner tube 33, a second inner tube 34, a hot nozzle 35 and a hot nozzle insert 36. The hot runner 31 is arranged in the first inner tube 33. The hot runner 31 is connected to the hot flow plate 2 and the hot nozzle 35 respectively. The second inner tube 34 is installed outside the first inner tube 33. The outer tube 32 is installed outside the second inner tube 34. The hot nozzle 35 is installed between the first inner tube 33 and the second inner tube 34 and is connected to the branch channel 41. An insulating air gap layer 37 is provided between the first inner tube 33 and the second inner tube 34 and between the second inner tube 34 and the outer tube 32 for thermal insulation of the injection molding material. The hot nozzle insert 36 is sleeved on the end of the second inner tube 34 close to the branch channel 41. The outer tube 32, the stripping insert 5 and the front mold core 4 jointly resist the hot nozzle insert 36 to limit the degree of freedom of the hot nozzle insert 36 in any direction.

[0045] In actual use, air gaps are set between the first inner tube 33 and the second inner tube 34 and between the second inner tube 34 and the outer tube 32 for heat insulation. The air gaps utilize the low thermal conductivity of air to effectively reduce the transfer of heat, which not only ensures the temperature stability of the material in the hot runner 31, but also reduces the thermal impact on other parts of the mold, thereby improving the overall performance and service life of the mold. The hot nozzle insert 36 is sleeved on the end of the second inner tube 34 close to the branch channel 41, and its degree of freedom is limited by the joint resistance of the outer tube 32, the stripping insert 5 and the front mold core 4. The setting of the hot nozzle insert 36 not only provides better positioning and protection for the hot nozzle 35, but also ensures the stability of the hot nozzle insert 36 during the injection molding process through the coordinated resistance of multiple components, thereby ensuring the accuracy and quality of injection molding. This design solves the problem that the hot nozzle is easily displaced and unstable in the mold. The design of the multi-layer pipeline 3 structure and the air gap helps to accurately control the temperature and flow state of the injection molding material. Stable temperature can ensure the fluidity and performance consistency of the material, and reduce product defects caused by temperature changes, such as bubbles, warping, etc. At the same time, precise control of material flow can make the filling of the product more uniform, improve the dimensional accuracy and appearance quality of the product. The multi-layer structure design of the pipeline 3 and the reasonable assembly method of each component make the mold more convenient for maintenance and repair. For example, if there is a problem with the hot runner 31 or the hot nozzle 35, this structural design can make it easier to disassemble and replace the relevant parts, reducing maintenance time and cost.

[0046] Specifically, the shunt path 411 has a first branch 4111, a second branch 4112 and a third branch 4113 which are arranged on the front mold core 4 and are connected in sequence. The first branch 4111 corresponds to the shunt path 411 one-to-one, and multiple first branches 4111 are arranged in the same plane. The second branch 4112 corresponds to the first branch 4111 one-to-one. The length direction of any second branch 4112 is perpendicular to the length direction of the corresponding first branch 4111. The third branch 4113 is distributed around the central axis of the second branch 4112, and the third branch 4113 is connected to the gate 42; the connecting point between any first branch 4111 and the second branch 4112 and / or the connecting point between any second branch 4112 and the third branch 4113 is provided with a semicircular protrusion 4114 for slowing down the impact of the molten injection material on the runner.

[0047] In actual use, when the injection molding machine injects the molten injection material into the hot runner 31 through the nozzle, the material first enters the first gentle portion 311 of the hot runner 31. As the material flows, the aperture gradually decreases through the first transition portion 312, and the material flow rate accelerates. Then it enters the second gentle portion 313, and the flow rate remains stable. Then it passes through the second transition portion 314, and the arc-shaped aperture changes so that the material flow rate is adjusted again. Then it enters the third gentle portion 315 and the third transition portion 316, and the aperture changes from small to large uniformly, and the material is smoothly transported to the runner 41. In the runner 41, the material enters the first branch 4111 from the hot runner 31. Since the multiple first branches 4111 are arranged in the same plane, the material can be quickly preliminarily distributed in the same plane. Then the material flows into the second branch 4112. Since the second branch 4112 is perpendicular to the first branch 4111, the flow direction of the material changes. In this process, the semicircular protrusion 4114 plays a role in mitigating the impact and reducing the damage of the material to the flow channel. Finally, the material enters the third branch 4113, and the surrounding third branch 4113 evenly transports the material to the gate 42, enters the injection molding space, and completes the injection molding of the mobile phone plastic middle frame.

[0048] Specifically, the gate 42 has a first feed port 421 with an arc fan-shaped structure and a second feed port 422 with a pin-point structure arranged on the mold core 43. The second feed port 422 is formed by the end of a portion of the second branch 4112. The first feed port 421 is connected to the third branch 4113 and there is a one-to-one correspondence between the two. The first feed port 421 is used to convey a large flow of injection molding material, and the second feed port 422 is used to convey a small flow of injection molding material.

[0049] In actual use, when the injection molding machine starts working, the molten injection material first enters the hot runner 31, and after being adjusted by the various flat parts and transition parts of the hot runner 31, it flows into the branch channel 41. In the branch channel 41, the material is transported by the first branch 4111, the second branch 4112 and the third branch 4113 to the gate 42. At this time, a large flow of injection material quickly enters the main part of the injection space through the first feed port 421 of the curved fan-shaped structure, and quickly fills the main part of the plastic middle frame of the mobile phone. At the same time, a small flow of injection material flows accurately to some detailed parts or areas that are difficult to fill, such as corners, small holes, etc., through the second feed port 422 of the pin-point structure. Through this gate 42 design, the produced mobile phone plastic middle frame has a smooth surface, high dimensional accuracy, and uniform filling of various parts without obvious defects.

[0050] Specifically, a heavy-duty connector 21 is provided on the hot flow plate 2 to connect to an external temperature control box. The temperature control box controls the heating parameters of the hot flow plate 2 to adjust the flow parameters of the injection molding material in the hot runner 31 so that the injection molding material flows smoothly in the hot runner 31 .

[0051] In actual use, for a specific plastic material, the temperature control box controls the temperature of the hot flow plate 2 within a specific range. At this temperature, the injection molding material can maintain good fluidity in the hot runner 31. After the injection molding material enters the hot runner 31 from the nozzle of the injection molding machine, the heating effect of the hot flow plate 2 keeps the material in a suitable temperature state at all times, avoiding the solidification or deterioration of fluidity of the material due to temperature drop during the flow process. At the same time, the temperature control box can adjust the heating parameters in real time according to the actual situation in the production process. If it is found that the flow rate of the material is too fast or too slow, the fluidity of the material can be changed by adjusting the temperature of the hot flow plate 2, thereby making the injection molding process smoother. In actual production, through this precise temperature control, the plastic middle frame of the mobile phone produced is of stable quality, high dimensional accuracy, and a smooth surface without defects.

[0052] Specifically, a stripping insert 5 is provided on the pipeline 3, and the stripping insert 5 is assembled and matched with the front mold core 4. One side of the stripping insert 5 protrudes outward to form a positioning boss 51 that cooperates with the front mold core 4. A space avoidance step 54 is formed between the positioning boss 51 and the stripping insert 5. The boss surface of the positioning boss 51 is provided with a through hole 52 along the thickness direction of the stripping insert 5 to cooperate with the diversion path 411. The diversion path 411 is formed in an L shape. A sprue hook 53 is provided in the through hole 52. One end of the sprue hook 53 protrudes into the diversion channel 41 through the intersection of the L-shaped flow channel to form a hook shape, and the other end is detachably connected to the stripping insert 5.

[0053] In actual use, in the process of producing the plastic middle frame of a mobile phone, after the injection molding machine injects the molten injection material into the hot runner 31 of the mold, the material enters the L-shaped shunt path 411 through the shunt channel 41. The stripping insert 5 is closely matched with the front mold core 4 to ensure that the material can be accurately filled into the injection space. After the injection molding is completed, the mold is opened and the stripping insert 5 begins to work. The hook-shaped end of the sprue hook 53 pulls the waste material in the flow channel, and as the mold opens, the waste material is separated from the product. Since the sprue hook 53 is detachably connected to the stripping insert 5, when the sprue hook 53 is worn or damaged, it can be easily replaced. Through the design of this stripping insert 5 and the sprue hook 53, the automatic separation of waste material is successfully achieved, greatly improving production efficiency. At the same time, the surface quality and dimensional accuracy of the product are also effectively guaranteed, reducing the scrap rate and reducing production costs.

[0054] Specifically, the stripping insert 5 and the front mold core 4 are both provided with cooling water channels 6 , which are arranged in a tic-tac-toe pattern around the central axis of the pipeline 3 , and the layout of the cooling water channels 6 is matched with the size of the mold core 43 .

[0055] In actual use, the stripping insert 5 and the front mold core 4 are provided with cooling water channels 6 in a tic-tac-toe pattern, which can cool the injection molded product in all directions around the central axis of the pipe 3. This layout increases the contact area between the cooling water channel 6 and the mold, improves the cooling efficiency, enables the injection molded product to be quickly cooled and shaped, and shortens the production cycle. The tic-tac-toe pattern ensures the uniformity of cooling. During the cooling process, the product in each part can be cooled more uniformly at the same time, avoiding problems such as product deformation and dimensional deviation caused by uneven cooling. This helps to improve the quality and dimensional accuracy of the product.

[0056] Specifically, a heating plate 22 is provided on the hot flow plate 2, and a heater 23 is embedded in the heating plate 22 for heating the hot runner 31. The heater 23 is electrically connected to the temperature control box for controlling the heating parameters of the heater 23; the side of the hot flow plate 2 away from the hot runner 31 is recessed inward to form an accommodating groove 24 for accommodating the heating plate 22, and the accommodating groove 24 extends along the length and / or width direction of the hot flow plate 2 to communicate with the outside to form a heat dissipation groove 25, and both sides of the length direction of the side of the hot flow plate 2 away from the hot runner 31 are recessed inward to form a step structure.

[0057] In actual use, during the production process of the plastic middle frame of the mobile phone, the heater 23 heats the hot runner 31 under the control of the temperature control box. When the heater 23 is working, the heat generated is transferred to the injection molding material in the hot runner 31 through the heating plate 22. At the same time, the design of the accommodating groove 24 and the heat dissipation groove 25 allows the excess heat generated by the heater 23 to be dissipated in time. For example, during continuous production, the heater 23 continues to work, and the heat dissipation groove 25 can effectively dissipate heat to the surrounding environment, keeping the temperature of the heat flow plate 2 stable. The step structure provides better support for the heat flow plate 2 to ensure that the heat flow plate 2 will not deform or displace during the injection molding process. Through the design of this hot flow plate 2, the produced plastic middle frame of the mobile phone is of stable quality and high dimensional accuracy. At the same time, the service life of the mold is also effectively extended, reducing production costs and maintenance frequency.

[0058] Specifically, one side of the front mold core 4 is recessed inward to form a first groove 44, and the side of the front mold core 4 facing away from the first groove 44 is recessed inward to form a second groove 45 for cooperating with the rear mold core. The number of the second grooves 45 is set to multiple, and the multiple second grooves 45 are distributed around the mold core 43.

[0059] In actual use, when producing the plastic middle frame of a mobile phone, the first groove 44 of the front mold core 4 can be used to install auxiliary components, such as positioning pins or sensors, as needed. The multiple second grooves 45 are precisely matched with the corresponding structures of the rear mold core to ensure the stability of the mold in the mold closing state. For example, for a specific model of mobile phone plastic middle frame, four second grooves 45 are designed that are evenly distributed around the mold core 43. During the injection molding process, the cooperation of these grooves with the rear mold core enables the injection material to be accurately filled into the injection molding space, and the produced middle frame has higher dimensional accuracy and a smooth surface without flash. At the same time, due to the high matching accuracy of the mold, the scrap rate in the production process is reduced, which improves production efficiency and economic benefits.

[0060] Specifically, a heat dissipation pad 7 is installed on the side of the front mold base plate 1 facing away from the hot runner 2, and a gate sleeve 11 is screwed on it for connecting with the nozzle of the injection molding machine. A positioning ring 71 is installed on the heat dissipation pad 7 for positioning connection with the nozzle of the injection molding machine, and the gate sleeve 11 is connected to the hot runner 31.

[0061] In actual use, when the injection molding machine starts working, the nozzle of the injection molding machine is accurately docked with the gate sleeve 11 on the front mold base plate 1 through the positioning ring 71. The heat dissipation pad 7 effectively dissipates the heat generated by the mold to ensure that the mold temperature is within a reasonable range. During the continuous production process, the heat dissipation pad 7 can continue to dissipate heat to prevent the mold from overheating. The positioning ring 71 ensures the precise connection between the nozzle and the gate sleeve 11 during each injection molding, so that the injection molding material can flow stably into the hot runner 31. If the gate sleeve 11 is worn, it can be quickly removed and replaced without affecting the production progress. Through this design, the production process of the plastic middle frame of the mobile phone is more stable and efficient, and the maintenance of the mold is also more convenient and quick.

[0062] The above contents are only preferred embodiments of the present invention. For ordinary technicians in this field, according to the concept of the present invention, there will be changes in the specific implementation methods and application scopes. The content of this specification should not be understood as limiting the present invention.

Claims

1. A mobile phone plastic middle frame mold that reduces the weight of the front mold glue inlet, characterized by: The invention comprises a front mold base plate (1), a heat flow plate (2) arranged on the front mold base plate (1), a pipeline (3) arranged on the heat flow plate (2), and a front mold core (4) arranged on the pipeline (3); a hot runner (31) is arranged on the pipeline (3) for conveying and heating the injection molding material; a branch runner (41) and a gate (42) are arranged on the front mold core (4); one side of the front mold core (4) protrudes outward to form a mold core (43) which cooperates with the mold cavity of the rear mold core to form an injection molding space; the gate (42) is connected to the branch runner (41) and the injection molding space; one end of the hot runner (31) is connected to the branch runner (41) The other end is connected to the nozzle of the injection molding machine, and the hot runner (2) provides heat for the injection molding material in the hot runner (31); the aperture size of the end of the hot runner (31) near the branch channel (41) changes continuously and transitionally, and the branch channel (41) has a plurality of branch channels (411). The plurality of branch channels (411) are distributed around the central axis of the pipeline (3) from the hot runner (31) and the connection point of the branch channel (41) to form a spoke-like structure, and the gate (42) is connected to the corresponding branch channel (411). The hot runner (31), the branch channel (41) and the gate (42) together constitute a casting system.

2. A mobile phone plastic middle frame mold with reduced weight of the front mold glue inlet according to claim 1, characterized in that: The pipeline (3) is arranged as a multi-layered tube structure, the hot runner (31) is arranged in the innermost layer of the multi-layered tube structure, a pore structure is arranged between the multi-layered tube structure for heat insulation of the injection molding material in the hot runner (31), and the hot runner (31) comprises a first flat portion (311), a first transition portion (312), a second flat portion (313), a second transition portion (314), a third flat portion (315), and a third transition portion (316) which are sequentially arranged and distributed along the length direction of the pipeline (3). 6), the smooth portions and the transition portions are arranged at intervals, the aperture sizes of the flow holes where the first, second and third smooth portions (315) are located are all unchanged, the aperture sizes of the flow holes where the first transition portion (312) and the second transition portion (314) are located are uniformly reduced from large, the aperture size of the flow hole where the third transition portion (316) is located is uniformly increased from small, the aperture changes of the first transition portion (312) and the third transition portion (316) are both linear, and the aperture change of the second transition portion (314) is arc-shaped.

3. A mobile phone plastic middle frame mold with reduced weight of the front mold glue inlet according to claim 1, characterized in that: The shunt path (411) comprises a first branch path (4111), a second branch path (4112) and a third branch path (4113) which are arranged on the front mold core (4) and are connected in sequence. The first branch path (4111) corresponds to the shunt path (411) one by one. A plurality of first branches (4111) are arranged on the same plane. The second branches (4112) correspond to the first branches (4111) one by one. The length direction of any second branch path (4112) corresponds to the length direction of the corresponding first branch path (4113). 111), the third branch (4113) is distributed around the central axis of the second branch (4112), and the third branch (4113) is connected to the gate (42); a semicircular protrusion (4114) for slowing down the impact of molten injection material on the flow channel is provided at the connection point between any first branch (4111) and the second branch (4112) and / or the connection point between any second branch (4112) and the third branch (4113).

4. A mobile phone plastic middle frame mold with reduced weight of the front mold glue inlet according to claim 3, characterized in that: The gate (42) comprises a first feed port (421) in an arc-shaped fan-shaped structure and a second feed port (422) in a pin-point structure, the second feed port (422) being formed by the end of a portion of the second branch (4112), the first feed port (421) being connected to the third branch (4113) and corresponding to each other one by one, the first feed port (421) being used to convey a large flow of injection molding material, and the second feed port (422) being used to convey a small flow of injection molding material.

5. The mobile phone plastic middle frame mold with reduced weight of the front mold glue inlet according to claim 1, characterized in that: A heavy-duty connector (21) is provided on the hot flow plate (2) and is connected to an external temperature control box. The temperature control box controls the heating parameters of the hot flow plate (2) to adjust the flow parameters of the injection molding material in the hot runner (31) so that the injection molding material flows smoothly in the hot runner (31).

6. A mobile phone plastic middle frame mold with reduced weight of the front mold glue inlet according to claim 1, characterized in that: A stripping insert (5) is provided on the pipeline (3), and the stripping insert (5) is assembled and matched with the front mold core (4). One side of the stripping insert (5) protrudes outward to form a positioning boss (51) that cooperates with the front mold core (4), and a space-avoiding step (54) is formed between the positioning boss (51) and the stripping insert (5). The boss surface of the positioning boss (51) is provided with a through hole (52) along the thickness direction of the stripping insert (5) to cooperate with the diversion path (411), and the diversion path (411) is formed in an L shape. A sprue hook (53) is provided in the through hole (52), and one end of the sprue hook (53) protrudes into the diversion path (41) through the intersection of the L-shaped flow channel to form a hook shape, and the other end is detachably connected to the stripping insert (5).

7. A mobile phone plastic middle frame mold with reduced weight of the front mold glue inlet according to claim 6, characterized in that: The stripping insert (5) and the front mold core (4) are both provided with cooling water channels (6). The cooling water channels (6) are arranged in a tic-tac-toe pattern and surround the central axis of the pipeline (3). The layout of the cooling water channels (6) is matched with the size of the mold core (43).

8. The mobile phone plastic middle frame mold with reduced weight of the front mold glue inlet according to claim 1, characterized in that: A heating plate (22) is provided on the hot flow plate (2), a heater (23) is embedded on the heating plate (22) for heating the hot runner (31), and the heater (23) is electrically connected to a temperature control box for controlling the heating parameters of the heater (23); a side of the hot flow plate (2) away from the hot runner (31) is recessed inward to form an accommodating groove (24) for accommodating the heating plate (22), the accommodating groove (24) extends along the length and / or width direction of the hot flow plate (2) to communicate with the outside to form a heat dissipation groove (25), and both sides of the length direction of the side of the hot flow plate (2) away from the hot runner (31) are recessed inward to form a step structure.

9. The mobile phone plastic middle frame mold with reduced weight of the front mold glue inlet according to claim 1, characterized in that: One side of the front mold core (4) is recessed inward to form a first groove (44), and one side of the front mold core (4) facing away from the first groove (44) is recessed inward to form a second groove (45) for cooperating with the rear mold core. The number of the second grooves (45) is set to be multiple, and the multiple second grooves (45) are distributed around the mold core (43).

10. The mobile phone plastic middle frame mold with reduced weight of the front mold glue inlet according to claim 1, characterized in that: A heat dissipation pad (7) is installed on the side of the front mold bottom plate (1) facing away from the hot flow plate (2), and a sprue sleeve (11) is screwed on it for connecting with the nozzle of the injection molding machine. A positioning ring (71) is installed on the heat dissipation pad (7) for positioning connection with the nozzle of the injection molding machine. The sprue sleeve (11) is connected with the hot runner (31).

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