Hot runner multi-point injection mold and injection molding method

Abstract

The present invention relates to the field of injection molding technology, and more particularly to a hot runner multi-point injection mold and an injection molding method, comprising an upper mold and a lower mold, each of which is provided with a mold cavity, the mold cavities being interconnected, the mold cavities being inclined, a diversion assembly being provided in the lower mold, the diversion assembly comprising a diversion rack, a feed pipe being provided on the top of the diversion rack, a main flow channel and a diversion flow channel being provided inside the diversion rack, the main flow channel being connected to the diversion flow channel, a main injection molding pipe being provided in the middle of the diversion rack corresponding to the main flow channel, one end of the main injection molding pipe being connected to the main flow channel, the other end of the main injection molding pipe being connected to the mold cavity, the main injection molding pipe being able to pass raw materials into the mold cavity, a plurality of diversion molding pipes being further provided on the diversion rack, one end of the diversion molding pipe being connected to the diversion flow channel, the other end of the diversion molding pipe being connected to the mold cavity, the diversion molding pipes being provided at different positions corresponding to the mold cavity, and the diversion molding pipes being able to inject raw materials into the mold cavity, thereby reducing the situation where the raw materials cannot fill the mold cavity.

Description

Technical Field

[0001] The present invention relates to the technical field of injection molding, in particular to a hot runner multi-point injection mold and an injection molding method. Background Art

[0002] Injection molding is to form a cavity by plates A and B, and inject raw materials into the cavity. Since the shape of the cavity corresponds to the shape of the required product, the product can be formed after waiting for the material to solidify. After the product is formed, plates A and B are separated, and the material can be taken out of the cavity to complete the processing.

[0003] Under the existing technology, most injection molds are equipped with an injection pipe with a larger cross-sectional area in the middle. The raw material is injected from the middle and pressurized, so that it flows along the cavity until the entire cavity is filled to complete the injection molding. However, this injection molding method is prone to insufficient pressure when injecting some large products, which makes it difficult for the raw material to fill the cavity and solidify prematurely, thereby affecting the product quality. Summary of the Invention

[0004] In order to solve the problem that the injection molding method under the existing technology is prone to insufficient pressure when injecting some large products, which makes it difficult for the raw material to fill the cavity and solidify prematurely, thereby affecting the product quality, this application provides a hot runner multi-point injection mold, and the specific solution is as follows.

[0005] A hot runner multi-point injection mold, comprising an upper mold and a lower mold, wherein cavities are provided in both the upper mold and the lower mold, wherein the cavities are interconnected, and wherein the cavities are inclined. A diverter assembly is provided on the lower side of the lower mold, wherein the diverter assembly comprises a diverter frame, wherein a feed pipe is provided on the side of the diverter frame away from the cavity, wherein a main flow channel and a diverter flow channel are provided inside the diverter frame, wherein the feed pipe is connected to the main flow channel, and the main flow channel is connected to the diverter flow channel, and wherein the diverter frame is close to the cavity. A main injection molding tube is provided in the middle corresponding to the main flow channel, one end of the main injection molding tube is connected with the main flow channel, and the other end of the main injection molding tube extends into the lower mold and is connected with the mold cavity, and the main injection molding tube can pass the raw material into the mold cavity. A plurality of diversion injection molding tubes are also provided on the diversion rack, one end of the diversion injection molding tube is connected with the diversion flow channel, and the other end of the diversion injection molding tube extends into the lower mold and is connected with the mold cavity. The diversion injection molding tubes are arranged at different positions corresponding to the mold cavity, and the diversion injection molding tubes can inject raw materials into the mold cavity.

[0006] By adopting the above technical solution, the inclined cavity can use gravity to assist the flow of raw materials. The diversion component cooperates with the feed pipe, main channel, diversion channel, main injection tube and diversion injection tube to inject raw materials into the cavity from multiple positions, ensuring that the raw materials fill the cavity evenly and efficiently, improving the injection molding quality and efficiency, and the cavity is inclined, and the injected raw materials can flow to various positions of the cavity under the action of gravity, thereby further improving the product quality.

[0007] Optionally, the mold cavity includes a connecting cavity and two main body cavities, and the connecting cavity is located between the two main body cavities and connects the two main body cavities.

[0008] By adopting the above technical solution, the mold cavity is set as a connecting cavity and two main cavities, and two products can be injection molded at one time. The connecting cavity is connected to the two main cavities, so that the raw materials can flow better between the two main cavities, which helps to achieve multi-point injection molding, ensure that the raw materials are evenly distributed in the entire mold cavity during the injection molding process, and improve the quality of injection molded products.

[0009] Optionally, the main injection molding tube is arranged at a position corresponding to the connecting cavity, and each of the branch injection molding tubes is arranged at a different position corresponding to the main cavity, and each of the branch injection molding tubes is arranged at intervals along the main cavity.

[0010] By adopting the above technical solution, the main injection tube injects raw materials into the corresponding connecting cavity, and the branch injection tube corresponds to the main cavity and injects raw materials along the main cavity intervals, so that the raw materials can enter the cavity from different positions, allowing the raw materials to fill the cavity more evenly, thereby improving the product molding quality and efficiency.

[0011] Optionally, the length of the diverter injection molding tube located in the middle is shorter than the diverter injection molding tube on the adjacent side and longer than the diverter injection molding tube on the other adjacent side, and the length of each diverter injection molding tube is set corresponding to the shape of the cavity.

[0012] By adopting the above technical solution, the diversion injection tubes at different positions can better adapt to the inclined cavity. During the injection molding process, the injection sequence and path can be reasonably arranged according to the positions of the cavity, and gravity can be used to allow the raw materials to flow more smoothly along the cavity. Under the action of gravity, the raw materials only need to be injected in sequence, and the raw materials will not be squeezed against each other to form a parting line, thereby improving the injection molding efficiency and product molding quality.

[0013] Optionally, a matching bevel is provided at one end of the diverter injection tube close to the cavity, and the matching bevel is provided to correspond to the shape of the cavity.

[0014] By adopting the above technical solution, the matching inclined surface of the diverter injection molding tube close to one end of the cavity is set to correspond to the shape of the cavity, which can make the diverter injection molding tube better adapt to the cavity, facilitate the accurate and smooth injection of raw materials into the cavity, and ensure the injection molding effect.

[0015] Optionally, a heating copper tube is provided on the diversion rack corresponding to the diversion injection molding tube, and the heating copper tube is arranged around the position of the diversion injection molding tube. The heating copper tube is used to heat the raw materials in the diversion flow channel. A heating copper tube is also provided on the diversion rack corresponding to the main injection molding tube, and the heating copper tube is also arranged around the position of the main injection molding tube. The heating copper tube is used to heat the raw materials in the main flow channel.

[0016] By adopting the above technical solution, a heating copper tube is arranged around the branch injection tube and the main injection tube, which can heat the raw materials in the main channel, prevent the raw materials from cooling and solidifying during the injection molding process, and ensure that the raw materials can be smoothly injected from the main injection tube and the branch injection tube into the inclined cavity composed of the main cavity and the connecting cavity. At the same time, a better injection molding effect can be achieved by cooperating with the multi-point injection molding method.

[0017] Optionally, a blocking rod is provided in the diversion injection molding tube, and the blocking rod is slidably connected in the diversion injection molding tube. An abutment slope is provided at one end of the diversion injection molding tube for passing the raw material. The blocking rod can abut against the abutment slope, and the blocking rod can seal the diversion injection molding tube after abutting against the abutment slope.

[0018] By adopting the above technical solution, a blocking rod is provided and a corresponding abutment slope is provided on the blocking rod. When the blocking rod abuts against the abutment slope inside the diversion injection molding tube, the flow channel can be blocked to prevent the outflow of raw materials, making the injection molding more controllable.

[0019] Optionally, a pneumatic driving component is provided on the diversion rack corresponding to the blocking rod, and the pneumatic driving component is used to push the blocking rod to move.

[0020] By adopting the above technical solution, the blocking rod is driven pneumatically, which has a fast response and low cost.

[0021] The present application also provides a hot runner multi-point injection molding method, including the above-mentioned hot runner multi-point injection mold, using the following scheme:

[0022] A. Inject the raw material into the diversion rack and wait for the raw material to fill the main channel and the diversion channel;

[0023] B. Injection starts from the diversion injection tube at the highest position of the cavity. During injection, the raw material flows along the cavity under the action of gravity.

[0024] C. When the raw material flows to the middle of the cavity, the main injection tube and the branch injection tube in the middle are opened for injection, pushing the raw material to flow further;

[0025] D. When the raw material flows to the diverter injection tube at the lowest position of the cavity, the diverter injection tube is opened for injection, and the raw material flows further along the cavity;

[0026] E. Wait for molding and demoulding to complete the injection molding.

[0027] By adopting the above technical solution, during injection molding, injection is first performed from the highest diversion injection molding tube, and the raw material can flow along the mold cavity. When the raw material flows to the middle, the diversion injection molding tube in the middle is also started at the same time. At this time, the raw materials flowing out of the two diversion injection molding tubes will not push and squeeze each other to form thin lines. The surface of the entire injection-molded product is smoother, and the quality of the product is improved.

[0028] In summary, this application has at least the following beneficial effects:

[0029] 1. The present application solves the problem that the injection molding method under the existing technology is prone to insufficient pressure when injecting some large products, which makes it difficult for the raw materials to fill the cavity and solidify prematurely, thereby affecting the product quality. The present application sets an inclined cavity and a corresponding diversion component. The diversion component can pass into the cavity from various positions, and the raw material can effectively fill the cavity, reducing the situation where the raw material cannot fill the cavity and solidifies, resulting in the impact on product quality.

[0030] 2. The present application also arranges diverter injection molding tubes of different lengths to align with the inclined cavity. The diverter injection molding tubes pass the raw materials in sequence. Under the action of gravity, the raw materials can reduce the mutual pushing and the appearance of thin lines on the product due to the mutual pushing, which can further improve the product quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a cross-sectional view of this embodiment.

[0032] Figure 2 It is a three-dimensional diagram of the lower mold in this embodiment.

[0033] Figure 3 It is a three-dimensional diagram of the diversion component in this embodiment.

[0034] Figure 4 2 is a cross-sectional view of the diversion component in this embodiment.

[0035] Figure 5 It is a three-dimensional diagram of the diversion component in this embodiment.

[0036] Description of reference numerals:

[0037] 1. Upper mold; 11. Cavity; 111. Main cavity; 112. Connecting cavity;

[0038] 2. Lower mold;

[0039] 3. Diverter assembly; 31. Diverter rack; 311. Feed pipe; 312. Main channel; 313. Diverter channel; 314. Main injection tube; 315. Diverter injection tube; 316. Heating copper tube; 317. Sealing rod; 318. Matching slope; 319. Pneumatic drive component; 32. Abutment slope. DETAILED DESCRIPTION

[0040] The present application is further described below in detail through specific embodiments in conjunction with the accompanying drawings.

[0041] A hot runner multi-point injection mold, such as Figure 1 and Figure 2 As shown, it includes an upper mold 1 and a lower mold 2. A cavity 11 is opened in each of the upper mold 1 and the lower mold 2. The cavities 11 can be connected to each other. The cavities 11 are all inclined. A diverter component 3 is provided on the lower side of the lower mold 2.

[0042] like Figure 1 and Figure 2 As shown, the mold cavity 11 includes a main body cavity 111 and a connecting cavity 112 . There are two main body cavities 111 . The connecting cavity 112 is located between the two main body cavities 111 and connects the two main body cavities 111 .

[0043] like Figure 3 and Figure 4 As shown, the diversion assembly 3 includes a diversion frame 31, a feed pipe 311 is provided on the side of the diversion frame 31 away from the cavity 11, a main flow channel 312 and a diversion flow channel 313 are provided inside the diversion frame 31, the feed pipe 311 is connected to the main flow channel 312, the main flow channel 312 is connected to the diversion flow channel 313, and a main injection pipe 314 is provided in the middle of the diversion frame 31 corresponding to the main flow channel 312, and one end of the main injection pipe 314 is connected to the main flow channel 312. The other end of the main injection tube 314 is connected to the mold cavity 11, and the main injection tube 314 can pass the raw material into the mold cavity 11. A plurality of diverter injection tubes 315 are also provided on the diverter rack 31. One end of the diverter injection tube 315 is connected to the diverter flow channel 313, and the other end of the diverter injection tube 315 is connected to the mold cavity 11. The diverter injection tubes 315 are arranged at different positions corresponding to the mold cavity 11, and the diverter injection tubes 315 can inject raw materials into the mold cavity 11. In specific implementation, the diverter injection tube 315 can inject raw materials at the same time as the main injection tube 314, so that the raw materials can be passed into the mold cavity 11 from different positions at the same time, with a faster flow speed and a higher pressure, which can reduce the situation where the raw material is difficult to fill the mold cavity 11, further improve the injection molding effect, and reduce the situation where the raw material solidifies when it does not completely fill the mold cavity 11.

[0044] like Figure 2 and Figure 3As shown, the main injection tube 314 is positioned corresponding to the connecting cavity 112, while the branch injection tube 315 is positioned corresponding to the main cavity 111. The branch injection tubes 315 are spaced apart along the main cavity 111. In practice, the raw material in the main injection tube 314 is first introduced into the connecting cavity 112, and then flows from the connecting cavity 112 to the main cavities 111 on both sides. This allows for simultaneous injection molding of two products, which can then be produced at once by cutting after demolding, further improving production efficiency.

[0045] like Figure 3 and Figure 4 As shown, the length of the diverter injection molding tube 315 located in the middle is shorter than the diverter injection molding tube 315 on the adjacent side and longer than the diverter injection molding tube 315 on the other adjacent side. The length between each diverter injection molding tube 315 corresponds to the shape of the mold cavity 11. In specific implementation, this embodiment is provided with three diverter injection molding tubes 315, and the diverter injection molding tube 315 in the middle is centered in length. The diverter injection molding tube 315 on one side is longer than the diverter injection molding tube 315 in the middle, and the diverter injection molding tube 315 on the other side is shorter than the diverter injection molding tube 315 in the middle. In this way, the diverter injection molding tube 315 can be aligned exactly with the inclined shape of the mold cavity 11, so that the raw material can be injected into the mold cavity 11 more accurately.

[0046] like Figure 3 and Figure 4 As shown, the end of the diverter injection tube 315 near the mold cavity 11 is provided with a matching bevel 318, which corresponds to the shape of the mold cavity 11. In a specific implementation, the matching bevel 318 exactly corresponds to the position of the mold cavity 11. After the raw material is injected, the matching bevel 318 can further maintain the product. In a specific implementation, the matching bevel 318 also exactly aligns with the shape of the molded product, reducing deformation of the product at the diverter injection tube 315 and further improving product quality.

[0047] like Figure 3 and Figure 4 As shown, a heating copper tube 316 is provided on the diverter frame 31 corresponding to the diverter injection molding tube 315. The heating copper tube 316 is arranged around the position of the diverter injection molding tube 315. The heating copper tube 316 is used to heat the raw material in the main channel 312. A heating copper tube 316 is also provided on the diverter frame 31 corresponding to the main injection molding tube 314. The heating copper tube 316 is also arranged around the position of the main injection molding tube 314. The heating copper tube 316 is used to heat the raw material in the diverter flow channel 313. In specific implementation, a heating copper tube 316 is provided for each diverter injection molding tube 315 and the main injection molding tube 314. When powered on, the temperature can be increased, thereby heating the raw material inside the diverter frame 31, reducing the situation where the raw material solidifies in the diverter frame 31, and reducing the situation where the raw material in the diverter frame 31 cools too quickly and blocks the internal part of the diverter frame 31, further improving the efficiency of injection molding.

[0048] like Figure 4 and Figure 5 As shown, a blocking rod 317 is provided in the diverter injection molding tube 315. The blocking rod 317 is slidably connected to the diverter injection molding tube 315. The end of the diverter injection molding tube 315 for passing the raw material is provided with an abutting inclined surface 32. The blocking rod 317 can abut against the abutting inclined surface 32. After the blocking rod 317 abuts against the abutting inclined surface 32, the diverter injection molding tube 315 can be blocked. A pneumatic drive 319 is provided on the diverter frame 31 corresponding to the blocking rod 317. The pneumatic drive 319 is used to push the blocking rod 317 to move. In a specific implementation, the pneumatic drive 319 provided on the diverter frame 31 includes a cylinder. The piston rod of the cylinder can directly drive the blocking rod 317 to move up and down. After the blocking rod 317 contacts the abutting inclined surface 32, the entire flow channel can be blocked, thereby blocking the raw material and preventing the raw material from passing out of this position.

[0049] The present application also provides a hot runner multi-point injection molding method, including the above-mentioned hot runner multi-point injection mold, using the following scheme:

[0050] A. Inject the raw material into the diverter rack 31 and wait for the raw material to fill the main channel 312 and the diverter channel 313. At this time, the heating copper tube 316 needs to be started to keep the raw material in a flowing state;

[0051] B. Injection begins with the diverter injection tube 315 at the highest position of the cavity 11. That is, the diverter injection tube 315, which is the longest in this embodiment, is at the highest position when the raw material is discharged. Therefore, the raw material flows along the cavity 11 under the action of gravity.

[0052] C. When the raw material flows to the middle of the cavity 11, the main injection tube 314 and the branch injection tube 315 located in the middle are opened for injection, pushing the raw material to flow further. The raw material at this time will be replenished into the raw material that has flowed to the middle, and will not push against the raw material that has been introduced previously, resulting in lines on the product due to mutual extrusion;

[0053] D. When the raw material flows to the diverter injection tube 315 at the lowest position of the cavity 11, that is, the diverter injection tube 315 with the smallest length in this embodiment, the diverter injection tube 315 is opened for injection molding, and the raw material flows further along the cavity 11. The principle at this position is the same, and the raw materials will not push each other and cause lines formed by mutual extrusion on the product;

[0054] E. Wait for molding and demoulding to complete the injection molding.

[0055] Working principle: By setting the diverter injection tubes 315 of different lengths to align with the inclined cavity 11, the diverter injection tubes 315 pass the raw materials in sequence. Under the action of gravity, the raw materials can reduce the mutual pushing and the appearance of thin lines on the product due to the mutual pushing, thereby improving the injection molding efficiency of the product and the injection molding quality of the product.

[0056] The above are preferred embodiments of the present application, and are not intended to limit the scope of protection of the present application. Therefore, any equivalent changes made based on the structure, shape, and principle of the present application should be included in the scope of protection of the present application.

Claims

1. A hot runner multi-point injection mold, comprising an upper mold (1) and a lower mold (2), wherein each of the upper mold (1) and the lower mold (2) is provided with a mold cavity (11), and the mold cavities (11) can be interconnected, characterized in that: The mold cavity (11) is arranged in an inclined manner. A diversion assembly (3) is arranged on the lower side of the lower mold (2). The diversion assembly (3) includes a diversion frame (31). A feed pipe (311) is arranged on the side of the diversion frame (31) away from the mold cavity (11). A main flow channel (312) and a diversion flow channel (313) are arranged inside the diversion frame (31). The feed pipe (311) is connected to the main flow channel (312), and the main flow channel (312) is connected to the diversion flow channel (313). A main injection pipe (314) is arranged in the middle of the diversion frame (31) on the side close to the mold cavity (11) corresponding to the main flow channel (312). The main injection pipe (314) is provided. 14) one end is communicated with the main flow channel (312), the other end of the main injection tube (314) extends into the lower mold (2) and communicates with the mold cavity (11), the main injection tube (314) can pass the raw material toward the mold cavity (11), the diversion frame (31) is further provided with a plurality of diversion injection tubes (315), one end of the diversion injection tube (315) is communicated with the diversion flow channel (313), the other end of the diversion injection tube (315) extends into the lower mold (2) and communicates with the mold cavity (11), the diversion injection tubes (315) are arranged at different positions corresponding to the mold cavity (11), and the diversion injection tubes (315) can inject the raw material toward the mold cavity (11); The mold cavity (11) comprises a connecting cavity (112) and two main body cavities (111), wherein the connecting cavity (112) is located between the two main body cavities (111) and connects the two main body cavities (111); The main injection molding tube (314) is arranged at a position corresponding to the connecting cavity (112), and each of the branch injection molding tubes (315) is arranged at a different position corresponding to the main cavity (111), and each of the branch injection molding tubes (315) is arranged at intervals along the main cavity (111); The length of the diverter injection molding tube (315) located in the middle is shorter than the diverter injection molding tube (315) on one adjacent side and longer than the diverter injection molding tube (315) on the other adjacent side, and the length of each diverter injection molding tube (315) is set corresponding to the shape of the cavity (11); A matching bevel (318) is provided at one end of the diverter injection tube (315) close to the mold cavity (11), and the matching bevel (318) is arranged to correspond to the shape of the mold cavity (11).

2. The hot runner multi-point injection mold according to claim 1, characterized in that: A heating copper tube (316) is provided on the diversion frame (31) corresponding to the diversion injection molding tube (315), and the heating copper tube (316) is arranged around the position of the diversion injection molding tube (315). The heating copper tube (316) is used to heat the raw material in the diversion flow channel (313). A heating copper tube (316) is also provided on the diversion frame (31) corresponding to the main injection molding tube (314), and the heating copper tube (316) is also arranged around the position of the main injection molding tube (314). The heating copper tube (316) is used to heat the raw material in the main flow channel (312).

3. The hot runner multi-point injection mold according to claim 1, characterized in that: A blocking rod (317) is provided in the diverter injection molding tube (315), and the blocking rod (317) is slidably connected to the diverter injection molding tube (315). An abutting inclined surface (32) is provided at one end of the diverter injection molding tube (315) for passing the raw material. The blocking rod (317) can abut against the abutting inclined surface (32). After the blocking rod (317) abuts against the abutting inclined surface (32), the diverter injection molding tube (315) can be blocked.

4. The hot runner multi-point injection mold according to claim 2, characterized in that: A pneumatic drive member (319) is provided on the diversion frame (31) corresponding to the blocking rod (317), and the pneumatic drive member (319) is used to push the blocking rod (317) to move.

5. A hot runner multi-point injection molding method, comprising the hot runner multi-point injection mold according to any one of claims 1 to 4, and employing the following scheme: A. Inject raw materials into the diverter frame (31) and wait for the raw materials to fill the main channel (312) and the diverter channel (313); B. Injection molding begins with the diverter injection molding tube (315) at the highest position of the cavity. During injection molding, the raw material flows along the cavity (11) under the action of gravity; C. When the raw material flows to the middle of the cavity (11), the main injection tube (314) and the branch injection tube (315) located in the middle are opened for injection molding, pushing the raw material to flow further; D. When the raw material flows to the diverter injection tube (315) at the lowest position of the cavity, the diverter injection tube (315) is opened for injection molding, and the raw material further flows along the cavity (11); E. Wait for molding and demoulding to complete the injection molding.

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