Exhaust insert, mold, mold system, and method of 3D printing an exhaust insert
By using a composite layer structure and a venting insert design with curved and folded venting channels, the problem of large and unevenly distributed pores in 3D-printed permeable steel was solved, resulting in plastic products with efficient gas discharge and high surface quality.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SHANGHAI ESU LASER TECH CO LTD
- Filing Date
- 2023-05-25
- Publication Date
- 2026-05-26
AI Technical Summary
Existing 3D-printed breathable steel has large and unevenly distributed pores, which cannot meet the requirements of high surface quality and has poor air permeability.
The exhaust insert adopts a composite layer structure, including a first layer of permeable steel and a second layer of permeable steel. An exhaust passage is opened on the first layer, and the two layers of permeable steel are overlapped. The exhaust passage has a curved and folded design and is printed using selective laser melting forming process. The scanning parameters are adjusted to control the aperture and exhaust efficiency.
It achieves efficient and uniform gas discharge, avoids product surface defects, improves the yield of plastic products, and meets high surface quality requirements.
Smart Images
Figure CN116494484B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of 3D printing technology, specifically to an exhaust insert, a mold, a mold system, and a method for 3D printing the exhaust insert. Background Technology
[0002] During the production process of injection molding, molten plastic is extruded into the mold cavity at high speed and high pressure by the injection molding machine. If the gas in the cavity cannot be discharged in time and smoothly during this process, it will cause trapped air, resulting in defects such as blackening, burning, material shortage, and weld lines in the plastic product.
[0003] Mold venting is usually achieved by creating venting grooves on inserts or setting ejector pins. However, in some complex structures, creating venting grooves and ejector pins can damage the structure of the inserts, rendering the venting inserts unusable. In such cases, the inserts are made of breathable steel for venting.
[0004] In the existing technology, in the process of printing inserts using breathable steel, the pore size of the 3D printed breathable steel is relatively large and the pore size distribution is uneven. It cannot be used in some scenarios with high surface quality requirements, and the breathable steel after printing has poor air permeability. This problem urgently needs to be solved. Summary of the Invention
[0005] Therefore, the technical problem to be solved by the present invention is to overcome the defects of the existing technology, which is that the ordinary pore size of the 3D printed ventilated steel is relatively large and the pore size distribution is uneven, making it unusable in some scenarios with high surface quality requirements, and the ventilated steel printed has poor air permeability. Thus, the present invention provides an exhaust insert, a mold, a mold system and a method for 3D printing an exhaust insert.
[0006] An exhaust insert includes: an insert body, the insert body being made of at least breathable steel and suitable for placement within a cavity of the mold, the insert body having a composite layer structure, comprising at least a first layer of breathable steel and a second layer of breathable steel, the first layer of breathable steel being laid on the second layer of breathable steel, and an exhaust passage being formed at least on the first layer of breathable steel.
[0007] Optionally, in the above-mentioned exhaust insert, the two adjacent layers of permeable steel are adapted to overlap.
[0008] Optionally, in the above-mentioned exhaust insert, the overlap distance between two adjacent layers of permeable steel is 0.1mm-0.5mm.
[0009] Optionally, in the above-mentioned exhaust insert, the insert body has a gap hole, and the diameter of the gap hole is between 10-80 μm.
[0010] Optionally, in the above-mentioned exhaust insert, the exhaust passage is formed on the first layer of breathable steel, and at least one end of the exhaust passage is open, so that gas can be discharged from the insert body through the opening along the exhaust passage.
[0011] Optionally, in the above-mentioned exhaust insert, the exhaust passage is arranged in a curved and folded manner, which includes at least one layer of sub-exhaust passages, and all of the sub-exhaust passages are opened parallel to each other on the insert body.
[0012] Optionally, in the above-mentioned exhaust insert, when the exhaust passage includes at least two layers of sub-exhaust passages, the sub-exhaust passages of each layer are connected end-to-end with the sub-exhaust passages of the adjacent layer.
[0013] A mold includes: a mold core, including a mold core body having a receiving cavity; and a venting insert, which is a venting insert as described above, the venting insert being disposed within the receiving cavity.
[0014] Optionally, in the above-mentioned mold, an air passage is provided on the mold core body, and the air passage is connected to the opening of the exhaust passage, so that the gas is suitable for being discharged out of the mold along the exhaust passage and the air passage.
[0015] A mold system includes: a mold, the mold being as described above; and an air suction device connected to an air passage of the mold.
[0016] Optionally, in the above mold system, an air nozzle is provided at the air outlet of the air passage, and the suction device is connected to the mold core body through the air nozzle; the suction device has a working state of forming negative pressure, and in the working state, the suction device is adapted to discharge the gas in the mold along the exhaust passage and the air passage to the outside of the mold.
[0017] A method for 3D printing an exhaust insert involves using selective laser melting (SLM) to form the insert or a mold. During the insertion process, a laser beam scans each layer of the insert layer by layer. When scanning the first layer of permeable steel, the scanning parameters are: laser beam power of 105-275W; and / or, scanning speed of 800-1200mm / s; and / or, path offset spacing of 0.1-0.22mm; and / or, printing layer thickness of 0.3-0.8mm. When scanning the second layer of permeable steel, the scanning parameters are: laser beam power of 125-245W; and / or, scanning speed of 900-1600mm / s; and / or, path offset spacing of 0.16-0.25mm; and / or, printing layer thickness of 0.03-0.08mm.
[0018] The technical solution of this invention has the following advantages:
[0019] 1. The present invention provides an exhaust insert, comprising: an insert body, the insert body being made of at least breathable steel and suitable for placement in the receiving cavity of the mold, the insert body having a composite layer structure, comprising at least a first layer of breathable steel and a second layer of breathable steel, the first layer of breathable steel being laid on the second layer of breathable steel, and an exhaust passage being formed at least on the first layer of breathable steel.
[0020] In this venting insert structure, the insert body is made of breathable steel and adopts a composite layer structure. The first layer of breathable steel is laid on the second layer of breathable steel, and venting channels are opened in at least the first layer of breathable steel. The small holes in the first layer of breathable steel structure have a one-way ventilation function, which is conducive to the smooth discharge of gas in the venting insert through the one-way holes, avoiding the defects of the venting holes affecting the product surface. At the same time, the venting channels opened in the first layer of breathable steel achieve a multi-way venting function, which is conducive to the smooth discharge of gas through the one-way holes in the first layer of breathable steel and through the multi-way holes in the second layer of breathable steel. There is no need to open the venting hole structure in the mold. The venting effect is good, and the breathable steel with small venting holes can be directly formed by metal 3D printing process to form the venting insert. This overcomes the defects of the existing technology, where the ordinary pore diameter of the 3D printed breathable steel is relatively large and the pore diameter distribution is uneven, which makes it unusable in some scenarios with high surface quality requirements, and the printed breathable steel has poor air permeability.
[0021] 2. In the exhaust insert provided by the present invention, the first layer of permeable steel and the second layer of permeable steel are adapted to be overlapped. By overlapping the permeable steel between two adjacent layers, the welding of the permeable steel between the two layers can be made more secure, avoiding cracking.
[0022] 3. In the exhaust insert provided by the present invention, the exhaust passage is arranged in a curved and folded manner, and includes at least one layer of sub-exhaust passage, all of which are opened parallel to each other on the insert body.
[0023] In this venting insert structure, by bending the venting passage, the passage between the gas generated in the mold during injection molding and the venting insert can be increased, making it easier for the gas to concentrate in the venting passage more quickly and in greater quantities, thus improving venting efficiency.
[0024] 4. The mold provided by the present invention includes: a mold core, including a mold core body having a receiving cavity; and a venting insert, which is a venting insert as described above, wherein the venting insert is disposed in the receiving cavity.
[0025] Because the mold uses a venting insert, it has all the beneficial effects of the venting insert. During the injection molding process, the gas in the cavity can be discharged smoothly and in a timely manner, without causing trapped air. This avoids defects such as blackening, burning, material shortage, and weld lines in the plastic products, resulting in a high product yield. Attached Figure Description
[0026] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0027] Figure 1 This is a schematic diagram of the overall structure of the exhaust insert provided in the first embodiment of the present invention;
[0028] Figure 2 for Figure 1 The front view of the exhaust insert shown;
[0029] Figure 3 for Figure 1 A top view of the exhaust insert shown;
[0030] Figure 4 This is a schematic diagram of the position mechanism of the first layer of ventilated steel and the second layer of ventilated steel when the venting insert and the mold core are integrally formed in the second embodiment of the present invention.
[0031] Figure 5 This is a schematic diagram showing the positional structure of the mold core and the venting insert provided in the second embodiment of the present invention;
[0032] Figure 6 This is a schematic diagram of the positional structure of the mold core body and the insert body provided in the second embodiment of the present invention;
[0033] Figure 7 This is a schematic diagram of the location structure of the air nozzle on the mold provided in the third embodiment of the present invention;
[0034] Figure 8 for Figure 7 A schematic diagram of the cross-sectional structure;
[0035] Figure 9 This is a schematic diagram showing the location and structure of the exhaust passage and the gas passage.
[0036] Figure 10 The image shows a magnified metallographic view of the breathable steel printed using the printing process described in Example 4.
[0037] Explanation of reference numerals in the attached figures:
[0038] 100. Venting insert; 200. Mold core; 300. Mold;
[0039] 1. Inlay body; 101. First layer of breathable steel; 102. Second layer of breathable steel; 103. Exhaust passage;
[0040] 2. Mold core body; 201. Receiving cavity;
[0041] 202. Air passage;
[0042] 3. Air valve. Detailed Implementation
[0043] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0044] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.
[0045] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.
[0046] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.
[0047] Example 1
[0048] This embodiment describes an exhaust insert 100, see [link to documentation]. Figures 1-4The exhaust insert 100 includes: an insert body 1, which is made of at least breathable steel and is suitable for placement in the receiving cavity 201 of the mold 300. It can be integrally formed with the mold 300. The insert body 1 has a composite layer structure, with at least a first layer of breathable steel 101 and a second layer of breathable steel 102. The first layer of breathable steel 101 is laid on the second layer of breathable steel 102, and an exhaust passage 103 is opened on the second layer of breathable steel 102.
[0049] In this embodiment, the insert body 1 is made of breathable steel, and the exhaust insert 100 adopts a composite layer structure. The first layer of breathable steel 101 is laid on the second layer of breathable steel 102, and an exhaust passage 103 is opened on at least the first layer of breathable steel 101. The small holes in the structure of the first layer of breathable steel 101 have a one-way ventilation function, which is conducive to the smooth exhaust of gas in the exhaust insert 100 through the one-way holes, avoiding the defects of the product surface caused by the exhaust holes. At the same time, the exhaust passage 103 is opened on the first layer of breathable steel 101, which realizes the multi-directional exhaust function. It is beneficial for the gas discharged through the one-way holes of the first layer of breathable steel 101 to be smoothly exhausted through the multi-directional holes on the second layer of breathable steel 102. There is no need to open an exhaust hole structure on the mold 300, the exhaust effect is good, and the exhaust insert 100 can be directly formed by metal 3D printing process to form breathable steel with small exhaust holes.
[0050] See Figure 4 In this embodiment, the exhaust insert 100 is provided with two layers of breathable steel, defined as the first layer of breathable steel 101 and the second layer of breathable steel 102. Of course, if the usage process and strength are met, it can also be set to three or four layers, depending on the actual use.
[0051] To ensure the strong bond between two adjacent layers of permeable steel, the two layers of permeable steel are overlapped. That is, when the insert body 1 uses two layers of permeable steel, the first layer of permeable steel 101 and the second layer of permeable steel 102 are overlapped. In specific installation, the overlap distance between the first layer of permeable steel 101 and the second layer of permeable steel 102 is 0.1mm-0.5mm. In this embodiment, a distance of 0.25mm is used to ensure the strong overlap between the two layers of permeable steel without compromising the rigidity of the insert body 1 itself. The overlap is achieved using an overlap remelting process.
[0052] The insert body 1 in this embodiment has a gap hole with a diameter between 10-80 μm. Setting the diameter of the gap hole between 10-80 μm ensures smooth venting while keeping the hole size small, which can meet the needs of some scenarios with high surface quality requirements and has a wider range of applications.
[0053] In this embodiment, the exhaust passage 103 can be opened on the body of the first layer of ventilated steel 101. At least one end of the exhaust passage 103 is open, and the gas is suitable to be discharged from the insert body 1 through the opening along the exhaust passage 103. In order to improve the exhaust efficiency, the exhaust passage 103 can be bent and folded. The exhaust passage 103 includes at least one layer of sub-exhaust passages 103. All the sub-exhaust passages 103 are opened in parallel on the insert body 1, that is, on the body of the first layer of ventilated steel 101. By bending the exhaust passage 103, the passage between the gas generated in the mold 300 during injection molding and the exhaust insert 100 can be increased, which makes it easier for the gas to concentrate in the exhaust passage 103 faster and more, thus improving the exhaust efficiency.
[0054] In more detail, when the exhaust passage 103 includes at least two layers of sub-exhaust passages 103, the sub-exhaust passages 103 of each layer are connected end-to-end with the sub-exhaust passages 103 of the adjacent layer.
[0055] Example 2:
[0056] This embodiment describes a mold 300, see [link]. Figure 5 and Figure 6 The mold 300 includes a mold core 200 and a venting insert 100. The mold core 200 includes a mold core body 2 with a receiving cavity 201. The venting insert 100 is the same as the venting insert 100 described in Embodiment 1. The venting insert 100 is placed in the receiving cavity 201. In actual installation, the venting insert 100 is integrally formed with the mold core 200, which can reduce processing resources and shorten the workpiece processing cycle.
[0057] Since the mold 300 in this embodiment adopts the venting insert 100 described in Embodiment 1, it has all the beneficial effects of the venting insert 100. During the injection molding process using the mold 300, the gas in the cavity can be discharged smoothly and in a timely manner, without causing trapped air, thereby avoiding the occurrence of defects such as blackening, burning, material shortage, and weld lines in the plastic product, resulting in a high product yield.
[0058] In order to quickly and efficiently discharge the gas in the exhaust passage 103 to the exhaust insert 100 through the mold core 200, an air passage 202 can be opened on the mold core body 2. The air passage 202 is connected to the opening of the exhaust passage 103. The gas is suitable for being discharged out of the mold 300 along the exhaust passage 103 and the air passage 202. Referring to the figure, the opening of the exhaust passage 103 in this embodiment is set to be open at both ends. Therefore, the corresponding air passage 202 is set to be two segments. The air passage 202 and the exhaust passage 103 have a right-angle transition passage. One end of the right-angle transition passage is connected to the exhaust passage 103 and the other end is connected to the air passage 202.
[0059] Example 3:
[0060] This embodiment describes a mold system, which includes a mold 300 and an air suction device. The mold 300 is the same as the mold 300 described in Embodiment 2. The air suction device is connected to the air passage 202 of the mold 300. Using the air suction device, the gas in the mold 300 can be quickly discharged to the outside of the mold 300.
[0061] Furthermore, the mold system in this embodiment adopts the mold 300 in embodiment 2, and therefore has all the beneficial effects of the mold 300.
[0062] In the mold system of this embodiment, see... Figure 7 and Figure 9 An air nozzle 3 is provided at the air outlet of the air passage 202. The suction device is connected to the mold core body 2 through the air nozzle 3. In actual use, the suction device has a working state of forming negative pressure. In this working state, the suction device is suitable for discharging the gas in the mold 300 out of the mold 300 along the exhaust passage 103 and the air passage 202. In actual use, the suction device adopts a negative pressure generator.
[0063] See Figure 7 An installation groove is made on the mold core body 2 corresponding to the outlet of the air passage 202. One end of the air nozzle 3 is inserted into the air passage 202, and the other end is located outside the air passage 202. There is a gap between the outer wall surface of the air nozzle 3 and the inner wall surface of the installation groove. The above-mentioned suction device has a suction pipe. The suction pipe is connected to the air nozzle 3. When it is necessary to exhaust gas from the mold 300, the suction device can be activated to efficiently suck the gas out of the mold 300, so as to achieve the effect of efficient gas discharge from the mold 300.
[0064] Example 4:
[0065] This embodiment describes a method for 3D printing an exhaust insert 100. Selective laser melting (SLM) is used to form the exhaust insert 100 in Embodiment 1. When the mold core 200 and the exhaust insert 100 are integrally formed in Embodiment 2, SLM can also be used to form the mold 300 in Embodiment 2. During the forming process, a laser beam scans each layer of the exhaust insert 100 layer by layer. When scanning the first layer of permeable steel 101, metal powder material is used for forming. The scanning parameters are: laser power of 105-275W, speed of 800-1200mm / s, path offset spacing of 0.1-0.22mm, 90° rotational filling, and a printing layer thickness of 0.3-0.8mm.
[0066] In practical use, the laser power can be set to 200W, the speed to 100mm / s, the path offset spacing to 0.15mm, the rotation angle to increase the filling to 90°, and the printing layer thickness to 0.55mm.
[0067] When scanning the second layer of breathable steel 102, metal powder material is used for forming. The scanning parameters are: laser beam power of 125-245W, scanning speed of 900-1600mm / s, path offset spacing of 0.16-0.025mm, and printing layer thickness of 0.03-0.08mm.
[0068] In practical use, the specific scanning parameters for scanning the second layer of breathable steel 102 can be set as follows: laser beam power of 185w, scanning speed of 1250mm / s, path offset spacing of 0.21mm, and printing layer thickness of 0.55mm.
[0069] The venting insert 100 is formed using selective laser melting (SLM) technology. This allows for the uniform arrangement of vent holes along the shape of the adhesive within the venting steel. The small holes formed on the first layer of venting steel 101 provide one-way ventilation, facilitating the smooth removal of gas from the mold 300 through these one-way holes. This prevents the vent holes from affecting the product surface. Furthermore, the first layer of venting steel 101 is printed using a sintering method that increases the filling angle by 90° through rotation. The size of the tiny vent holes is ensured by offsetting the laser path spacing, and the one-way through holes are formed by controlling the laser power and speed. This process also maintains the high strength, high hardness, and corrosion resistance required by the mold 300.
[0070] When printing the second layer of breathable steel 102, the size of the tiny exhaust holes is ensured by offsetting the laser path spacing, and the connection of the formed multi-holes is ensured by laser power and speed. This facilitates the smooth concentration of gas discharged from the unidirectional holes on the first layer of breathable steel 101 into the exhaust passage 103 through the multidirectional holes on the second layer of breathable steel 102.
[0071] During the printing process, adjust the squeegee and substrate, the powder particle size is 15-75um, and the substrate heating temperature is 100-150℃.
[0072] The breathable steel printing process in this embodiment can be used in applications requiring high surface finish, such as polishing, to meet the high polishing requirements.
[0073] Comparative Example 1:
[0074] The difference between Comparative Example 1 and Example 1 is that no exhaust passage is provided on the exhaust insert, while other printing parameters are set the same.
[0075] Comparative Example 2:
[0076] The difference between Comparative Example 2 and Example 1 is that Comparative Example 2 uses a cast-molded insert.
[0077] Performance testing
[0078] Testing methods: Metallurgical microscopy was used to test the prepared products.
[0079] Data Analysis
[0080] Table 1 shows the test parameters for Examples 1-3 and Comparative Examples 1 and 2.
[0081]
[0082] As can be seen from Examples 1-4 and Comparative Examples 1-2 and Table 1, the air permeability of the mold inserts obtained by the preparation process of this application can reach 0.002%-0.009%.
[0083] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.
Claims
1. An exhaust insert, characterized in that, include: The insert body (1) is made of at least breathable steel and is suitable for placement in the receiving cavity (201) of the mold. The insert body (1) has a composite layer structure, which includes at least a first layer of breathable steel (101) and a second layer of breathable steel (102). The first layer of breathable steel (101) is laid on the second layer of breathable steel (102), and an exhaust passage (103) is opened on at least the first layer of breathable steel (101). At least one end of the exhaust passage (103) is provided to be open, and gas is adapted to be discharged from the insert body (1) through the opening along the exhaust passage (103); The exhaust passage (103) is arranged in a curved and folded manner, and includes at least one layer of sub-exhaust passages, all of which are opened parallel to the insert body (1); When the exhaust passage (103) includes at least two layers of sub-exhaust passages, the sub-exhaust passages of each layer are connected end-to-end with the sub-exhaust passages of the adjacent layer.
2. The exhaust insert according to claim 1, characterized in that, The two adjacent layers of permeable steel are suitable for overlapping.
3. The exhaust insert according to claim 2, characterized in that, The overlap spacing between two adjacent layers of breathable steel is 0.1mm-0.5mm.
4. The exhaust insert according to any one of claims 1-3, characterized in that, The insert body (1) has a gap hole with a diameter between 10-80 μm.
5. A mold, characterized in that, include: The mold core (200) includes a mold core body (2) having a receiving cavity (201); The exhaust insert (100) is the exhaust insert (100) according to any one of claims 1-4, and the exhaust insert (100) is disposed in the receiving cavity (201).
6. The mold according to claim 5, characterized in that, An air passage (202) is provided on the mold core body (2), and the air passage (202) is connected to the opening of the exhaust passage (103), so that the gas is suitable to be discharged out of the mold along the exhaust passage (103) and the air passage (202).
7. A mold system, characterized in that, include: Mold (300), wherein the mold (300) is the mold (300) according to any one of claims 5-6; An air suction device is provided, which is connected to the air passage (202) of the mold.
8. The mold system according to claim 7, characterized in that, An air nozzle (3) is provided at the air outlet of the air passage (202), and the air suction device is connected to the mold core body (2) through the air nozzle (3); The suction device has a negative pressure working state, in which the suction device is adapted to discharge the gas in the mold out of the mold along the exhaust passage (103) and the air passage (202).
9. A method for 3D printing an venting insert, characterized in that, The venting insert (100) of any one of claims 1-4 is formed using a selective laser melting forming process, or the venting insert in the mold of claim 5 or 6 is formed. During the forming process of the venting insert (100), each layer of the venting insert (100) is scanned layer by layer using a laser beam. When scanning the first layer of permeable steel (101), the scanning parameters are: the power of the laser beam is 105-275W; and / or, the scanning speed is 800-1200mm / s; and / or, the path offset spacing is 0.1-0.22mm; and / or, the printing layer thickness is 0.3-0.8mm. When scanning the second layer of breathable steel (102), the scanning parameters are as follows: the power of the laser beam is 125-245W; and / or, the scanning speed is 900-1600mm / s; and / or, the path offset spacing is 0.16-0.25mm; and / or, the printing layer thickness is 0.03-0.08mm.