Rotary inner side core-pulling mechanism of injection mold
By setting a cylinder-driven rotary core-pulling mechanism inside the injection mold, and using the cooperation of pins and sliding holes to realize the conversion of linear motion to rotary motion, the problems of baffle deformation and mold space occupation in traditional core-pulling structures are solved, and compact mold, low cost and efficient core pulling are achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- ZHEJIANG KAIHUA MOLDS
- Filing Date
- 2026-04-01
- Publication Date
- 2026-06-05
AI Technical Summary
The core-pulling structure of traditional injection molds is prone to causing the baffle to deform or break, and it also occupies external space of the mold, increasing manufacturing costs.
The rotary core-pulling mechanism driven by an internal hydraulic cylinder converts linear motion into rotary motion through the engagement of a pin and a sliding hole, eliminating the need for external transmission components and simplifying the structure.
It effectively reduces the external space of the mold, lowers manufacturing costs, and improves the smoothness of the core-pulling action and the service life of the mold.
Smart Images
Figure CN122143283A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to injection molds, and more particularly to a rotating inner core-pulling mechanism for injection molds. Background Technology
[0002] When producing plastic parts using injection molds, if a downward-facing arc-shaped plate is set on one side of the plastic part, and an upward-facing vertical plate is set on the other end of the arc-shaped plate, with an inward-facing baffle on top of the vertical plate, an arc-shaped groove is formed between the arc-shaped plate, the vertical plate, and the baffle. The baffle prevents the core-pulling structure from directly extracting the arc-shaped groove. The traditional method is to reduce the inclination angle of the baffle and forcefully remove the baffle and the arc-shaped groove. However, this method is prone to baffle deformation or breakage, making it difficult to guarantee the product qualification rate and significantly shortening the mold's lifespan. Alternatively, some designs have incorporated a hydraulic cylinder on the outer wall of the fixed mold plate. The piston rod of the hydraulic cylinder is connected to a rack, which meshes with a gear. The gear is connected to a rotating core-pulling block via a shaft. The hydraulic cylinder drives the rack to move, the rack drives the gear to rotate, and the gear drives the rotating core-pulling block to rotate and extract the arc-shaped groove. The disadvantages of this structure are: 1. The hydraulic cylinder, rack, gear, and other transmission components occupy external space of the mold, resulting in an increased mold volume; 2. The addition of the rack and gear makes the structure more complex, increasing the mold's manufacturing cost. Summary of the Invention
[0003] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a rotating inner core-pulling mechanism for injection molds that does not occupy external space of the mold, reduces mold volume, has a simple structure, and lowers mold manufacturing costs.
[0004] The technical solution of the rotating inner core-pulling mechanism of an injection mold according to the present invention 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 assembly is provided on the lower plate between the mold feet. The ejector rod of the injection molding machine passes through the through hole and cooperates with the ejector assembly. 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 to be injection molded is located in the mold cavity. A downward-facing arc-shaped plate is provided on one side of the plastic part. An upward-facing vertical plate is provided at the other end of the arc-shaped plate. An inward-facing baffle is provided at the top of the vertical plate. A cavity is formed between the arc-shaped plate, the vertical plate, and the baffle. The arc-shaped groove includes a first hydraulic cylinder in the fixed template, a rotating groove below the fixed template, a rotating core-pulling block in the rotating groove, the rotating core-pulling block being rotatably connected to the fixed template via a rotating shaft, a connecting handle at the upper part of the rotating core-pulling block with a transverse sliding hole in the connecting handle, the piston rod head of the first hydraulic cylinder engaging with the sliding hole of the connecting handle via a pin, and the lower part of the rotating core-pulling block engaging with the inner wall of the arc-shaped groove. A horizontal sliding groove is provided on the moving template, and a side core-pulling slider is provided on the horizontal sliding groove. One end of the side core-pulling slider engages with the outer wall of the vertical plate and the baffle, and the other end of the side core-pulling slider is driven by a second hydraulic cylinder.
[0005] Furthermore, the ejector assembly includes an upper ejector plate and a lower ejector plate. The ejector rod of the injection molding machine passes through the perforation and cooperates with the lower ejector plate. Ejector pins are provided on the upper and lower ejector plates, and the ejector pins cooperate with the bottom of the plastic part.
[0006] Furthermore, a bearing is provided on the outer wall of the pin, and the bearing cooperates with the sliding hole.
[0007] The beneficial effects of the rotating inner core-pulling mechanism for injection molds of the present invention are: 1. The first hydraulic cylinder is set inside the fixed template. The piston rod of the first hydraulic cylinder directly drives the pin to cooperate with the sliding hole of the connecting handle to realize the rotation and core pulling action of the rotating core pulling block. There is no need to set hydraulic cylinders, racks, gears and other transmission components outside the mold, which effectively saves external space of the mold, reduces the size of the mold, and makes the overall structure of the mold more compact. Second, the conversion from linear motion to rotary motion is achieved by using a pin and sliding hole combination, eliminating the need for complex transmission mechanisms such as racks and gears, greatly simplifying the mold structure and reducing the processing difficulty and manufacturing cost of the mold. Third, the second hydraulic cylinder drives the side core-pulling slider to pull the core outward first, leaving enough space for the rotation of the rotating core-pulling block, avoiding motion interference between the rotating core-pulling block and the side core-pulling slider, and ensuring the smooth progress of the core-pulling action. Attached Figure Description
[0008] Figure 1 This is a schematic diagram of the mold closing state structure of the rotating inner core-pulling mechanism of an injection mold according to the present invention; Figure 2 This is a schematic diagram of the structure of the side core-pulling slider in the outward core-pulling state; Figure 3 This is a schematic diagram of the rotating core-pulling block rotating out of the arc-shaped groove. Figure 4 This is a schematic diagram of the ejection state of the plastic part after mold opening of the rotating inner core-pulling mechanism of an injection mold according to the present invention.
[0009] In the diagram, 1. Upper cover plate; 2. Lower cover plate; 3. Fixed template; 4. Perforation; 5. Mold foot; 6. Moving template; 7. Plastic part; 8. Curved plate; 9. Vertical plate; 10. Baffle; 11. Curved groove; 12. First hydraulic cylinder; 13. Rotating groove; 14. Rotating core-pulling block; 15. Rotating shaft; 16. Connecting handle; 17. Sliding hole; 18. Pin; 19. Horizontal sliding groove; 20. Side core-pulling slider; 21. Second hydraulic cylinder; 22. Upper ejector plate; 23. Lower ejector plate; 24. Ejector pin; 25. Bearing; 30. Ejector rod. Detailed Implementation
[0010] To enable those skilled in the art to better understand the technical solutions of the present invention, preferred embodiments of the present invention 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 the present invention. To better illustrate this embodiment, some components in the drawings may be omitted, enlarged, or reduced, and do not represent the actual size of the product. 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 the present invention.
[0011] It should be noted that the terms "comprising" and "having," and any variations thereof, in the specification, claims, and accompanying drawings of this invention 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 construction; 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 invention according to the specific circumstances.
[0012] In the description of this invention, it should be understood that the terms "upper," "lower," "left," "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 the invention 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 the invention. The terms "first" and "second" are also used only for the sake of brevity in description and do not indicate or imply relative importance.
[0013] To further illustrate the content, features, and effects of this invention, the invention will be described in detail below with reference to the accompanying drawings and examples, but this should not be construed as limiting the invention.
[0014] This invention relates to a rotating inner core-pulling mechanism for injection molds, such as... Figure 1 — Figure 4As shown, the system includes an upper platen 1 and a lower platen 2. A fixed template 3 is provided under the upper platen 1. A through hole 4 is provided in the lower platen 2. Mold feet 5 are provided on the lower platen 2. An ejector assembly is provided on the lower platen 2 between the mold feet 5. The ejector rod 30 of the injection molding machine passes through the through hole 4 and cooperates with the ejector assembly. 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. A downward-facing arc-shaped plate 8 is provided on one side of the plastic part 7. An upward-facing vertical plate 9 is provided at the other end of the arc-shaped plate 8. An inward-facing baffle 10 is provided on the top of the vertical plate 9. An arc-shaped groove 11 is formed between the arc-shaped plate 8, the vertical plate 9, and the baffle 10. A first hydraulic cylinder 12 is provided in the fixed template 3. A rotating groove 13 is provided under the fixed template 3, and a rotating core-pulling block 14 is provided in the rotating groove 13. The rotating core-pulling block 14 is rotatably connected to the fixed template 3 via a rotating shaft 15. A connecting handle 16 is provided on the upper part of the rotating core-pulling block 14, and a horizontal sliding hole 17 is provided in the connecting handle 16. The piston rod head of the first oil cylinder 12 is engaged with the sliding hole 17 of the connecting handle 16 via a pin 18. The lower part of the rotating core-pulling block 14 is engaged with the inner wall of the arc-shaped groove 11. A horizontal sliding groove 19 is provided on the moving template 6, and a side core-pulling slider 20 is provided on the horizontal sliding groove 19. One end of the side core-pulling slider 20 is engaged with the outer wall of the vertical plate 9 and the baffle 10, and the other end of the side core-pulling slider 20 is driven by the second oil cylinder 21.
[0015] Furthermore, the ejector assembly includes an upper ejector plate 22 and a lower ejector plate 23. The ejector rod 30 of the injection molding machine passes through the through hole 4 and cooperates with the lower ejector plate 23. Ejector pins 24 are provided on the upper ejector plate 22 and the lower ejector plate 23, and the ejector pins 24 cooperate with the bottom of the plastic part 7.
[0016] Furthermore, a bearing 25 is provided on the outer wall of the pin 18, and the bearing 25 cooperates with the sliding hole 17. With the bearing 25, frictional resistance is effectively reduced, making the rotary core-pulling action more flexible and reliable, and extending the service life of the mechanism.
[0017] This invention discloses a rotating inner core-pulling mechanism for an injection mold. After the plastic part 7 is injection molded, the piston rod of the second cylinder 21 drives the side core-pulling slider 20 to move outward along the horizontal slide groove 19, so that the head of the side core-pulling slider 20 is pulled out of the outer wall of the vertical plate 9 and the baffle 10, leaving enough space below the rotating groove 13. Then, the piston rod of the first cylinder 12 drives the pin 18 to move downward. The pin 18 engages with the sliding hole 17, causing one end of the connecting handle 16 to rotate downward. Since the side core-pulling slider 20 has been pulled out and enough space has been left, one end of the connecting handle 16 can rotate downward smoothly, while the other end of the connecting handle 16 drives the rotating core-pulling block 14 to rotate upward around the rotating shaft 15. The lower part of the rotating core-pulling block 14 is rotated upward to pull out the arc-shaped groove 11, and the rotating core-pulling block 14 is disengaged from the baffle 10. At this time, the injection molding machine drives the lower cover plate 2 to move downward. The lower cover plate 2 drives the mold foot 5, ejector assembly, moving platen 6, plastic part 7, side core-pulling slider 20, and second oil cylinder 21 to move downward together. The upper cover plate 1, fixed platen 3, first oil cylinder 12, and rotating core-pulling block 14 remain stationary, so that the mold opens from the fixed platen 3 and moving platen 6. The rotating core-pulling block 14 is completely separated from the plastic part 7. Finally, the ejector rod 30 of the injection molding machine passes through the through hole 4 and drives the lower ejector plate 23, upper ejector plate 22, and ejector pin 24 to move upward. The ejector pin 24 pushes the plastic part 7, which has completed the core-pulling, upward to demold.
[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 of the present invention. However, the scope of patent protection of the present invention shall still be determined by the scope defined in the appended claims.
Claims
1. A rotating inner core-pulling mechanism for an injection mold, comprising an upper plate (1) and a lower plate (2), wherein a fixed template (3) is provided under the upper plate (1), a through hole (4) is provided in the lower plate (2), a mold foot (5) is provided on the lower plate (2), an ejector assembly is provided on the lower plate (2) between the mold feet (5), an ejector rod (30) of an injection molding machine passes through the through hole (4) and cooperates with the ejector assembly, 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, a downward arc plate (8) is provided on one side of the plastic part (7), an upward vertical plate (9) is provided at the other end of the arc plate (8), an inward baffle (10) is provided on the top of the vertical plate (9), and an arc groove (11) is formed between the arc plate (8), the vertical plate (9) and the baffle (10), characterized in that: The fixed template (3) is provided with a first oil cylinder (12), and a rotating groove (13) is opened under the fixed template (3). A rotating core-pulling block (14) is provided in the rotating groove (13). The rotating core-pulling block (14) is rotatably connected to the fixed template (3) via a rotating shaft (15). A connecting handle (16) is provided on the upper part of the rotating core-pulling block (14). A horizontal sliding hole (17) is opened in the connecting handle (16). The piston rod head of the first oil cylinder (12) is engaged with the sliding hole (17) of the connecting handle (16) via a pin (18). The lower part of the rotating core-pulling block (14) is engaged with the inner wall of the arc groove (11). A horizontal sliding groove (19) is opened on the moving template (6). A side core-pulling slider (20) is provided on the horizontal sliding groove (19). One end of the side core-pulling slider (20) is engaged with the outer wall of the vertical plate (9) and the baffle (10). The other end of the side core-pulling slider (20) is driven by a second oil cylinder (21).
2. The rotating inner core-pulling mechanism for an injection mold as described in claim 1, characterized in that: The ejector assembly includes an upper ejector plate (22) and a lower ejector plate (23). The ejector rod (30) of the injection molding machine passes through the through hole (4) and cooperates with the lower ejector plate (23). Ejector pins (24) are provided on the upper ejector plate (22) and the lower ejector plate (23), and the ejector pins (24) cooperate with the bottom of the plastic part (7).
3. The rotating inner core-pulling mechanism for an injection mold as described in claim 1, characterized in that: The outer wall of the pin (18) is provided with a bearing (25), which is matched with the sliding hole (17).