Injection mold gear and rack large angle oblique side core pulling mechanism
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- ZHEJIANG KAIHUA MOLDS
- Filing Date
- 2025-09-11
- Publication Date
- 2026-08-07
AI Technical Summary
[0002]采用注塑模具生产塑料件时，若塑料件的下部有斜孔或者斜槽，已有技术通常是在顶出结构的上、下顶针板上布置斜顶，在斜顶将塑料件向上顶出脱模的同时，斜顶斜向移动抽出塑料件的斜孔或者斜槽，该结构简单，制造方便，但是当斜孔或者斜槽的倾斜角度较大（以中心线，大于30°时），若继续采用斜顶的方式，斜顶所需的行程较长，占用更大的空间，且模具的开模距离也要增加，并且斜顶杆的倾斜角度过大，使用时间久了，容易弯折，影响使用寿命；另外，也有人采用在动模板内部设置斜向的油缸，油缸的倾斜角度与斜孔或者斜槽的倾斜角度相对应，通过油缸带动斜抽芯杆直接抽芯斜孔或者斜槽，但是油缸体积大，占用大量动模板的内部空间，不利于动模板内部冷却水路的布置，导致动模板体积增大，因此需要采用更大吨位的注塑机才能带动，增加了制造成本，并且模具需要在开模前，先通过油缸抽芯，才能进行开模，油缸的抽芯动作占用开模时间，导致生产效率低
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Figure CN224602189U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to injection molds, and in particular to a gear and rack core-pulling mechanism with a large angle of inclination on the side. Background Technology
[0002] When producing plastic parts using injection molds, if the lower part of the plastic part has an oblique hole or groove, existing technology typically involves arranging oblique ejectors on the upper and lower ejector plates of the ejection structure. While the oblique ejector pushes the plastic part upwards for demolding, it also moves obliquely to extract the oblique hole or groove. This structure is simple and easy to manufacture. However, when the angle of inclination of the oblique hole or groove is large (greater than 30° from the centerline), continuing to use oblique ejectors results in a longer stroke, occupies more space, and increases the mold opening distance. Furthermore, the excessively large angle of inclination of the ejector pin makes it prone to bending over time. This affects the service life. Alternatively, some manufacturers use an inclined cylinder inside the moving mold plate, with the cylinder's tilt angle corresponding to the tilt angle of the inclined hole or groove. The cylinder drives the inclined core-pulling rod to directly pull the core from the inclined hole or groove. However, the cylinder is large, occupying a lot of internal space of the moving mold plate, which is not conducive to the arrangement of cooling water channels inside the moving mold plate. This leads to an increase in the size of the moving mold plate, so a larger tonnage injection molding machine is required to drive it, increasing manufacturing costs. Furthermore, the mold needs to be pulled by the cylinder before it can be opened, and the core-pulling action of the cylinder takes up mold opening time, resulting in low production efficiency. Summary of the Invention
[0003] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a gear and rack large-angle oblique side core pulling mechanism for injection molds that is simple in structure, easy to manufacture, does not increase the mold volume, reduces manufacturing costs, and is beneficial for core pulling and demolding of large-angle oblique holes in plastic parts.
[0004] The technical solution of this utility model for a gear and rack large-angle oblique side core-pulling mechanism for injection molds is as follows: It includes an upper plate and a lower plate. A fixed template is provided under the upper plate. A through hole is formed in the lower plate. Mold feet are provided on the lower plate. An ejector and linkage assembly is provided on the lower plate between the mold feet. A movable template is provided on the mold feet. A mold cavity is formed between the movable template and the fixed template. A plastic part is injection molded in the mold cavity. An inclined column is provided at the lower part of the plastic part, and a large-angle oblique hole is formed in the inclined column. The ejector and linkage assembly includes an ejection structure and a linkage structure. The ejection structure includes a first upper ejector plate, a first lower ejector plate, and an ejector pin. The ejector pin passes through the movable template and contacts the plastic part. The linkage structure includes a second upper ejector plate and a second lower ejector plate. The ejector rod of the injection molding machine passes through a through hole and engages with the second lower ejector plate. The second upper ejector plate is located below the first lower ejector plate, and there is a free stroke between the second upper ejector plate and the first lower ejector plate. A first rack is provided on the second upper ejector plate and the second lower ejector plate. A gear hole and a slanted core-pulling hole are opened in the moving template. A gear is provided in the gear hole. The first rack passes through the first upper ejector plate, the first lower ejector plate, and the moving template and meshes with the gear. A slanted core-pulling rod is provided in the slanted core-pulling hole. The upper end of the slanted core-pulling rod engages with a large-angle slanted hole, and a second rack is provided at the lower end of the slanted core-pulling rod. The second rack meshes with the gear.
[0005] Furthermore, a reset rod is provided on the first upper ejector plate and the first lower ejector plate, and the upper end of the reset rod passes through the moving template and cooperates with the fixed template.
[0006] Furthermore, a guide rod is provided between the lower cover plate and the moving template, and guide holes are respectively provided in the first upper ejector plate, the first lower ejector plate, the second upper ejector plate and the second lower ejector plate, and the guide holes cooperate with the guide rod.
[0007] The beneficial effects of this utility model of a gear and rack large-angle inclined side core-pulling mechanism for injection molds are as follows: By setting an ejection structure and a linkage structure on the lower cover plate between the mold feet, a free stroke is formed between the ejection structure and the linkage structure. When the mold opens, the first rack of the linkage structure meshes with the gear, and the gear meshes with the second rack, thereby driving the inclined core-pulling rod to pull out the large-angle inclined hole of the plastic part at an angle. When the linkage structure and the ejection structure are in contact, the ejection structure is driven to eject the plastic part out of the mold. This solution has a simple structure, is easy to manufacture, occupies little internal space in the mold, does not increase the mold volume, reduces the manufacturing cost of the mold, and ensures that the large-angle inclined hole of the plastic part can be smoothly pulled out and demolded. Attached Figure Description
[0008] Figure 1 This is a schematic diagram of the mold closing state structure of the gear and rack large-angle oblique side core-pulling mechanism of the injection mold of this utility model; Figure 2This is a schematic diagram of the mold opening state structure of the gear and rack large-angle oblique side core-pulling mechanism of the injection mold of this utility model; Figure 3 This is a schematic diagram of the structure in which the linkage moves upward, causing the inclined core-pulling rod to be pulled out of the inclined core-pulling hole. Figure 4 This is a schematic diagram of the structure in which the ejection and linkage components move upward to eject the plastic part.
[0009] In the diagram, 1. Upper cover plate; 2. Lower cover plate; 3. Fixed mold plate; 4. Through hole; 5. Mold foot; 6. Moving mold plate; 7. Plastic part; 8. Angled column; 9. Large angle angled hole; 10. First upper ejector plate; 11. First lower ejector plate; 12. Ejector pin; 13. Second upper ejector plate; 14. Second lower ejector plate; 15. Free stroke; 16. First rack; 17. Gear hole; 18. Angled core-pulling hole; 19. Gear; 20. Angled core-pulling rod; 21. Second rack; 22. Reset rod; 23. Guide rod; 24. Guide hole; 25. Cavity surface; 30. Ejector pin of injection molding machine. Detailed Implementation
[0010] To enable those skilled in the art to better understand the technical solution of this utility model, the preferred embodiments of this utility model are described below in conjunction with specific examples. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote elements with the same or similar functions throughout. However, it should be understood that the drawings are for illustrative purposes only and should not be construed as limiting this utility model. To better illustrate this embodiment, some parts in the drawings may be omitted, enlarged, or reduced, and do not represent the actual product size. It is understandable for those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings. The positional relationships described in the drawings are for illustrative purposes only and should not be construed as limiting this utility model.
[0011] It should be noted that the terms "comprising" and "having," and any variations thereof, in the specification, claims, and accompanying drawings of this utility model are intended to cover non-exclusive inclusion. The terms "set," "equipped with," "installed," "connected," and "connected" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; 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, or an internal connection between two mechanisms, elements, or components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.
[0012] In the description of this utility model, it should be understood that the terms "upper," "lower," "left," and "right," 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 this utility model and for simplifying the description, and do not indicate or imply that the mechanism 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 this utility model. The terms "first," "second," "third," and "fourth" are also used only for the sake of brevity in the description and do not indicate or imply relative importance.
[0013] To further illustrate the content, features, and effects of this utility model, the following detailed description of this utility model is provided in conjunction with the accompanying drawings and examples, but it should not be construed as a basis for limiting this utility model.
[0014] This utility model relates to a large-angle oblique side core-pulling mechanism for gears and racks in injection molds, such as... Figure 1 — Figure 4 As shown, the assembly includes an upper plate 1 and a lower plate 2. A fixed template 3 is provided under the upper plate 1. A through hole 4 is formed in the lower plate 2. Mold feet 5 are provided on the lower plate 2. An ejector and linkage assembly is provided on the lower plate 2 between the mold feet 5. A movable template 6 is provided on the mold feet 5. A mold cavity is formed between the movable template 6 and the fixed template 3. A plastic part 7 is injection molded in the mold cavity. An inclined column 8 is provided at the lower part of the plastic part 7. A large-angle inclined hole 9 is formed in the inclined column 8. The ejector and linkage assembly... The linkage assembly includes an ejection structure and a linkage structure. The ejection structure includes a first upper ejector plate 10, a first lower ejector plate 11, and ejector pins 12. The first upper ejector plate 10 and the first lower ejector plate 11 are fixed together by fasteners. The ejector pin 12 passes through the moving template 6 and contacts the plastic part 7 (the attached figure shows only a portion of the ejector pins; in actual injection molds, the number of ejector pins 12 can be determined according to the structure and shape of the plastic part 7, so that the ejector pins 12 can push the plastic part 7 upward in a balanced manner). The linkage structure includes a second upper ejector plate 13 and a second lower ejector plate 14. The second upper ejector plate 13 and the second lower ejector plate 14 are fixed together by fasteners. The ejector rod 30 of the injection molding machine passes through the through hole 4 and cooperates with the second lower ejector plate 14. The second upper ejector plate 13 is located below the first lower ejector plate 11, and there is a free stroke 15 between the second upper ejector plate 13 and the first lower ejector plate 11. The second upper ejector plate 13 and the second lower ejector plate 14 are provided with a first... A rack 16 is provided. A gear hole 17 and an oblique core-pulling hole 18 are provided in the moving template 6. A gear 19 is provided in the gear hole 17. The first rack 16 passes through the first upper ejector plate 10, the first lower ejector plate 11, and the moving template 6 and meshes with the gear 19. An oblique core-pulling rod 20 is provided in the oblique core-pulling hole 18. The upper end of the oblique core-pulling rod 20 is engaged with a large-angle oblique hole 9. A second rack 21 is provided at the lower end of the oblique core-pulling rod 20 and meshes with the gear 19.
[0015] Furthermore, a reset rod 22 is provided on the first upper ejector plate 10 and the first lower ejector plate 11. The upper end of the reset rod 22 passes through the moving template 6 and cooperates with the fixed template 3. With the reset rod 22, on the one hand, when the mold is closed and reset, the reset rod 22 contacts the bottom of the fixed template 3, ensuring that the first upper ejector plate 10 and the first lower ejector plate 11 can be reset smoothly and accurately. On the other hand, when the mold is closed and reset, the reset rod 22 contacts the bottom of the fixed template 3, preventing the ejector pin 12 from hitting the cavity surface 25 of the fixed template 3 (the cavity surface is the inner wall of the cavity of the fixed template), which would damage the cavity surface and affect the formation of corresponding marks on the injection molded plastic part 7.
[0016] Furthermore, a guide rod 23 is provided between the lower cover plate 2 and the moving template 6. Guide holes 24 are respectively provided in the first upper ejector plate 10, the first lower ejector plate 11, the second upper ejector plate 13, and the second lower ejector plate 14, and the guide holes 24 cooperate with the guide rod 23. With the guide rod 23, the up and down movement of the first upper ejector plate 10, the first lower ejector plate 11, the second upper ejector plate 13, and the second lower ejector plate 14 can be guided, making their movements more precise and stable.
[0017] This utility model discloses a gear and rack large-angle oblique side core-pulling mechanism for injection molds. After the plastic part 7 is injection molded, the injection molding machine drives the lower cover plate 2 to move downwards. The lower cover plate 2 drives the mold feet 5, ejector structure, linkage structure, moving platen 6, gear 19, oblique core-pulling rod 20, and plastic part 7 to move downwards together, while the upper cover plate 1 and fixed platen 3 remain stationary, so that the mold gradually opens from the fixed platen 3 and moving platen 6. When the second lower ejector plate 14 of the connecting structure moves to the position of the ejector rod 30 of the injection molding machine, the ejector rod 30 of the injection molding machine stops the movement of the second upper ejector plate 13 and the second lower ejector plate 14. The second lower ejector plate 14 causes the first rack 16 to stop moving. Since there is a free stroke 15 between the ejection structure and the linkage structure at this time, the lower cover plate 2 can continue to drive the ejection structure, mold foot 5, moving mold plate 6, gear 19, inclined core-pulling rod 20, and plastic part 7 to move downwards. The first rack 16 drives the gear 19 to rotate, and the gear 19 drives the second rack 21 to move downwards at an angle. The second rack 21 drives the inclined core-pulling rod 20 to pull the plastic part 7 out of the large-angle inclined hole 9 along the inclined core-pulling hole 18, completing the core-pulling action. When the first lower ejector plate 11 of the ejection structure moves downwards to be in contact with the second upper ejector plate 13 of the linkage structure... Upon contact, the ejector pin 30 of the injection molding machine stops moving along with the first upper ejector plate 10, the first lower ejector plate 11, the ejector pin 12, the second upper ejector plate 13, the second lower ejector plate 14, and the first rack 16. The ejector pin 12 stops moving along with the plastic part 7 that has completed core pulling. Meanwhile, the lower platen continues to drive the mold feet 5 and the moving platen 6 downwards, causing the plastic part 7 to dislodge from the moving platen 6. Finally, the injection molding machine drives the lower platen 2, mold feet 5, ejection structure, linkage structure, moving platen 6, gear 19, and inclined core-pulling rod 20 upwards together, gradually closing the mold. At this point, the upper part of the first rack 16 contacts the lower part of the fixed platen 3, and the fixed platen 3... The first rack 16, the second upper ejector plate 13, and the second lower ejector plate 14 are pushed back to their original positions. The first rack 16 drives the gear 19 to rotate, and the gear 19 drives the second rack 21 and the inclined core-pulling rod 20 to move upward along the inclined core-pulling hole 18. When the reset rod 22 contacts the bottom of the fixed template 3, the fixed template 3 pushes the reset rod 22, the first upper ejector plate 10, and the first lower ejector plate 11 to move downward to their original positions until the upper ends of the first rack 16 and the reset rod 22 are flush with the upper end of the moving template 6. The ejection structure and the linkage structure are then reset to their original positions, and the first lower ejector plate 11 and the second upper ejector plate 13 form a free stroke again, ready for the next action.
[0018] Although the embodiments of this application disclose the above-described methods, the content is merely an implementation method adopted for ease of understanding. Any person skilled in the art should understand that any modifications and changes in the form and details of the implementation can be made without departing from the spirit and scope disclosed in this utility model. However, the patent protection scope of this utility model shall still be determined by the scope defined in the appended claims.
Claims
1. A gear and rack large-angle oblique side core-pulling mechanism for injection molds, comprising an upper platen (1) and a lower platen (2), wherein a fixed template (3) is provided under the upper platen (1), a through hole (4) is provided in the lower platen (2), a mold foot (5) is provided on the lower platen (2), an ejector and linkage assembly is provided on the lower platen (2) between the mold feet (5), a movable template (6) is provided on the mold foot (5), a mold cavity is formed between the movable template (6) and the fixed template (3), a plastic part (7) is injection molded in the mold cavity, an inclined column (8) is provided at the lower part of the plastic part (7), and a large-angle oblique hole (9) is provided in the inclined column (8), characterized in that: The ejection and linkage assembly includes an ejection structure and a linkage structure. The ejection structure includes a first upper ejector plate (10), a first lower ejector plate (11), and an ejector pin (12). The ejector pin (12) passes through the moving template (6) and contacts the plastic part (7). The linkage structure includes a second upper ejector plate (13) and a second lower ejector plate (14). The ejector rod (30) of the injection molding machine passes through the perforation (4) and cooperates with the second lower ejector plate (14). The second upper ejector plate (13) is located below the first lower ejector plate (11). There is a free travel (15) between the second upper ejector plate (13) and the first lower ejector plate (11). A first rack (16) is provided on the upper ejector plate (13) and the second lower ejector plate (14). A gear hole (17) and a slanted core-pulling hole (18) are provided in the moving template (6). A gear (19) is provided in the gear hole (17). The first rack (16) passes through the first upper ejector plate (10), the first lower ejector plate (11), and the moving template (6) and meshes with the gear (19). A slanted core-pulling rod (20) is provided in the slanted core-pulling hole (18). The upper end of the slanted core-pulling rod (20) is engaged with the large-angle slanted hole (9). A second rack (21) is provided at the lower end of the slanted core-pulling rod (20). The second rack (21) meshes with the gear (19).
2. The injection mold gear and rack large-angle oblique side core-pulling mechanism as described in claim 1, characterized in that: The first upper ejector plate (10) and the first lower ejector plate (11) are provided with a reset rod (22), the upper end of the reset rod (22) passes through the moving template (6) and cooperates with the fixed template (3).
3. The injection mold gear and rack large-angle oblique side core-pulling mechanism as described in claim 1, characterized in that: A guide rod (23) is provided between the lower cover plate (2) and the moving template (6). Guide holes (24) are respectively opened in the first upper ejector plate (10), the first lower ejector plate (11), the second upper ejector plate (13) and the second lower ejector plate (14), and the guide holes (24) cooperate with the guide rod (23).