Injection mold ejection and demolding mechanism without ejector plate

Abstract

An ejector plateless demolding mechanism for an injection mold includes an upper plate and a lower plate. A fixed template is mounted on the lower plate, and a movable template is mounted on the lower plate. Both the movable and fixed templates have plastic parts. The movable template has a horizontal sliding hole and a vertical sliding hole. A plug is mounted at one end of the horizontal sliding hole, and a horizontal slider is mounted within the horizontal sliding hole. A first spring is positioned between the horizontal slider and the plug. The other end of the horizontal slider passes through the horizontal sliding hole and engages with a compression reset structure. A through hole is formed in the horizontal slider, and a first inclined guide surface is provided on the inner wall of one side of the through hole. A vertical slider is mounted within the vertical sliding hole, and an ejector rod is mounted on the top of the vertical slider. The ejector rod passes through the vertical sliding hole and engages with the plastic parts. A second spring is mounted on the outer wall of the ejector rod. The bottom end of the vertical slider is inserted into the through hole, and a second inclined guide surface is provided on one side of the vertical slider, engaging with the first inclined guide surface.

Description

Technical Field

[0001] This invention relates to injection molds, and more particularly to an ejector plateless ejection and demolding mechanism for injection molds. Background Technology

[0002] In injection molds, after a plastic part is injection molded, an ejector structure is usually needed to eject it and demold it. Traditional injection molds typically have mold feet between the lower platen and the moving platen, forming a space where an ejector plate and ejector pins can be placed. After the mold opens, a hydraulic cylinder drives the ejector plate, which in turn drives the ejector pins to eject the plastic part. The disadvantages of this structure are: 1. The addition of mold feet increases the height and volume of the entire mold, requiring a larger tonnage injection molding machine to operate it, thus increasing equipment costs; 2. The addition of mold feet, ejector plate, ejector pins, hydraulic cylinders, and other structures increases the manufacturing cost of the mold. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of existing technologies and provide an injection mold ejection and demolding mechanism without ejector plates that reduces mold volume, has a simple structure, and lowers mold manufacturing costs.

[0004] The technical solution of the ejection and demolding mechanism for injection molds without ejector plates of the present invention is as follows: It includes an upper plate and a lower plate. A fixed template is provided under the upper plate, and a movable template is provided on the lower plate. A mold cavity is formed between the movable template and the fixed template, and a plastic part is injection molded in the mold cavity. A transverse sliding hole and a vertical sliding hole are formed in the movable template, and the transverse sliding hole communicates with the vertical sliding hole. A plug is provided at one end of the transverse sliding hole, and a transverse slider is provided in the transverse sliding hole. A first spring is provided between the transverse slider and the plug, and the other end of the transverse slider passes through the transverse sliding hole and... The extrusion reset structure is matched with a through hole in the horizontal slider. A first inclined guide surface is provided on the inner wall of the through hole near the first spring. A vertical slider is provided in the vertical sliding hole. A push rod is provided on the upper end of the vertical slider. The push rod passes through the vertical sliding hole and matches with the plastic part. A second spring is provided on the outer wall of the push rod. The upper end of the second spring contacts the moving template, and the lower end of the second spring contacts the vertical slider. The lower end of the vertical slider is inserted into the through hole. A second inclined guide surface is provided on one side of the vertical slider. The second inclined guide surface matches the first inclined guide surface.

[0005] Furthermore, the extrusion reset structure includes a wedge set under the fixed template, the wedge being fixed to a fixed block by fasteners, the fixed block being fixed to the fixed template by fasteners, a third inclined guide surface being provided on one side of the wedge, and a fourth inclined guide surface being provided on one end of the transverse slider near the wedge, the fourth inclined guide surface cooperating with the third inclined guide surface.

[0006] Furthermore, the wedge is located on the upper part of the third inclined guide surface and has a first straight surface, and the transverse slider is located on the upper part of the fourth inclined guide surface and has a second straight surface, the second straight surface cooperating with the first straight surface.

[0007] Furthermore, a positioning groove is provided under the horizontal slider, and a positioning pin is provided in the moving template, with the upper end of the positioning pin cooperating with the positioning groove.

[0008] Furthermore, a guide rod is provided on the side of the plug near the transverse slider, and the first spring is sleeved on the outer wall of the guide rod.

[0009] The beneficial effects of the ejector plateless ejection and demolding mechanism for injection molds of the present invention are as follows: Through the cooperation of the horizontal slider, the vertical slider, the first inclined guide surface, the second inclined guide surface, the first spring, the second spring, and the extrusion reset structure, the lifting action of the ejector rod is realized, thereby completing the ejection and demolding of the plastic part. The entire mechanism does not require complex structures such as mold feet, ejector plates, and hydraulic cylinders, effectively reducing the mold volume and height. The overall structure is simple and compact, and the operation is reliable and stable. It can be produced using injection molding machines with smaller tonnage, reducing equipment costs and mold manufacturing costs. It is particularly suitable for producing smaller-sized plastic parts and plastic parts with smaller clamping forces on the moving mold plate, achieving a significant reduction in manufacturing costs. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the mold closing state structure of the ejector plateless ejection and demolding mechanism of the injection mold of the present invention; Figure 2 This is a schematic diagram of the mold opening state structure of the ejection and demolding mechanism of the injection mold without ejector plate according to the present invention; Figure 3 This is a schematic diagram of the ejection state of the plastic part in the injection mold ejection and demolding mechanism without ejector plate of the present invention; Figure 4 This is a schematic diagram of the vertical slider structure; Figure 5 This is a schematic diagram of the horizontal slider.

[0011] In the diagram, 1. Upper cover plate; 2. Lower cover plate; 3. Fixed template; 4. Moving template; 5. Plastic part; 6. Horizontal sliding hole; 7. Vertical sliding hole; 8. Plug; 9. Horizontal slider; 10. First spring; 11. Through hole; 12. First inclined guide surface; 13. Vertical slider; 14. Top rod; 15. Second spring; 16. Second inclined guide surface; 17. Wedge; 18. Fixing block; 19. Third inclined guide surface; 20. Fourth inclined guide surface; 21. First straight surface; 22. Second straight surface; 23. Positioning groove; 24. Positioning pin; 25. Guide rod. Detailed Implementation

[0012] 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 parts in the drawings may be omitted, enlarged, or reduced, and do not represent the actual product dimensions. 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.

[0013] 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.

[0014] 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.

[0015] 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.

[0016] This invention relates to an ejector plateless demolding mechanism for injection molds, such as... Figure 1 — Figure 5As shown, the device includes an upper cover plate 1 and a lower cover plate 2. A fixed template 3 is provided under the upper cover plate 1, and a movable template 4 is provided on the lower cover plate 2. A mold cavity is formed between the movable template 4 and the fixed template 3, and a plastic part 5 is injection molded in the mold cavity. A transverse sliding hole 6 and a vertical sliding hole 7 are provided in the movable template 4. The transverse sliding hole 6 and the vertical sliding hole 7 are connected. A plug 8 is provided at one end of the transverse sliding hole 6, and a transverse slider 9 is provided in the transverse sliding hole 6. A first spring 10 is provided between the transverse slider 9 and the plug 8. The other end of the transverse slider 9 passes through the transverse sliding hole 6 and cooperates with the extrusion reset structure. A through-hole is provided in the transverse slider 9. Hole 11, with a first inclined guide surface 12 provided on the inner wall of the hole 11 near the first spring 10, a vertical slider 13 provided in the vertical sliding hole 7, a top rod 14 provided on the upper end of the vertical slider 13, the top rod 14 passing through the vertical sliding hole 7 and cooperating with the plastic part 5, a second spring 15 provided on the outer wall of the top rod 14, the upper end of the second spring 15 contacting the moving template 4, the lower end of the second spring 15 contacting the vertical slider 13, the lower end of the vertical slider 13 inserted into the hole 11, a second inclined guide surface 16 provided on one side of the vertical slider 13, the second inclined guide surface 16 cooperating with the first inclined guide surface 12.

[0017] Furthermore, the extrusion reset structure includes a wedge 17 set under the fixed template 3, the wedge 17 being fixed to the fixed block 18 by fasteners, the fixed block 18 being fixed to the fixed template 3 by fasteners, a third inclined guide surface 19 being provided on one side of the wedge 17, and a fourth inclined guide surface 20 being provided at one end of the transverse slider 9 near the wedge 17, the fourth inclined guide surface 20 cooperating with the third inclined guide surface 19.

[0018] Furthermore, the wedge 17 is provided with a first straight surface 21 on the upper part of the third inclined guide surface 19, and the transverse slider 9 is provided with a second straight surface 22 on the upper part of the fourth inclined guide surface 20, with the second straight surface 22 cooperating with the first straight surface 21. Since the inner wall of the fixed template 3 is still in contact with the outer wall of the plastic part 5 in the early stage of mold opening, if the inner wall of the fixed template 3 is not completely separated from the outer wall of the plastic part 5 and the plastic part 5 is pushed upward, it is easy to cause the plastic part 5 to have excessive clamping force and make it difficult to push it out. With the first straight surface 21 and the second straight surface 22, the wedge 17 can cooperate with the second straight surface 22 of the horizontal slider 9 through the first straight surface 21 in the early stage of mold opening, so that the wedge 17 can still hold the horizontal slider 9, and the horizontal slider 9 can delay moving to the right. In this way, the vertical slider 13 and the ejector rod 14 can delay driving the plastic part 5 to be pushed upward until the inner wall of the fixed template 3 is completely separated from the plastic part 5, and the first straight surface 21 also disengages from the second straight surface 22. At this time, the first spring 10 can push the horizontal slider 9 to move to the right.

[0019] Furthermore, a positioning groove 23 is formed under the horizontal slider 9, and a positioning pin 24 is provided in the moving template 4, with the upper end of the positioning pin 24 engaging with the positioning groove 23. The engagement of the positioning pin 24 and the positioning groove 23 can effectively limit the travel of the horizontal slider 9, prevent excessive movement, and ensure the accuracy and stability of the mechanism's operation.

[0020] Furthermore, a guide rod 25 is provided on the side of the plug 8 near the transverse slider 9, and the first spring 10 is sleeved on the outer wall of the guide rod 25. The guide rod 25 can guide the first spring 10, preventing the first spring 10 from shifting or twisting during compression and recovery, and ensuring the reliability of the spring's operation.

[0021] This invention discloses an ejector plateless demolding mechanism for injection molds. After the plastic part 5 is injection molded, the injection molding machine drives the lower platen 2 to move downwards. The lower platen 2 drives the moving mold plate 4, the plug 8, the horizontal slider 9, the vertical slider 13, and the plastic part 5 (i.e., all components on the moving mold side) to move downwards together, while the upper platen 1, the fixed mold plate 3, and the extrusion reset structure remain stationary, allowing the mold to gradually open from the fixed mold plate 3 and the moving mold plate 4. When the wedge 17 of the extrusion reset structure disengages from one end of the horizontal slider 9, the first spring 10 (the elastic force of the first spring 10 must be greater than the elastic force of the second spring 15) pushes the horizontal slider 9 to the right under the action of the elastic restoring force. The first inclined guide surface 12 in the through hole 11 of the horizontal slider 9 cooperates with the second inclined guide surface 16 that is aligned with the right side of the vertical slider 13. Under the guidance of the first inclined guide surface 12 and the second inclined guide surface 16, the vertical slider 13 is driven to move upwards along the vertical sliding hole 7. The vertical slider 13 then presses the second spring 15 upwards. 5. The vertical slider 13 drives the ejector pin 14 to move upward, and the ejector pin 14 pushes the plastic part 5 upward to demold. When the mold is closed, the injection molding machine drives the lower cover plate 2 to move upward. The lower cover plate 2 drives the moving mold plate 4 and all parts on one side of the moving mold to move upward. The wedge 17 under the fixed mold plate 3 gradually approaches the horizontal slider 9. The third inclined guide surface 19 of the wedge 17 first contacts and engages with the fourth inclined guide surface 20 of the horizontal slider 9. As the wedge 17 continues to move downward, the horizontal slider 9 is pushed to the left by the guiding action of the third inclined guide surface 19 and the fourth inclined guide surface 20. The horizontal slider 9 compresses the first spring 10. At the same time, the second spring 15 pushes the vertical slider 13 to return to its original position under the action of elastic restoring force. Through the cooperation of the second inclined guide surface 16 and the first inclined guide surface 12, the vertical slider 13 also pushes the horizontal slider 9 to the left. The vertical slider 13 drives the ejector pin 14 to move downward, so that the upper end face of the ejector pin 14 retracts below the cavity surface of the moving mold plate 4, and the mold is closed.

[0022] 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. An ejector plateless demolding 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), and a movable template (4) is provided on the lower platen (2), wherein a mold cavity is formed between the movable template (4) and the fixed template (3), and a plastic part (5) for injection molding is contained in the mold cavity, characterized in that: The moving template (4) has a horizontal sliding hole (6) and a vertical sliding hole (7). The horizontal sliding hole (6) and the vertical sliding hole (7) are connected. A plug (8) is provided at one end of the horizontal sliding hole (6). A horizontal slider (9) is provided in the horizontal sliding hole (6). A first spring (10) is provided between the horizontal slider (9) and the plug (8). The other end of the horizontal slider (9) passes through the horizontal sliding hole (6) and cooperates with the extrusion reset structure. A through hole (11) is provided in the horizontal slider (9). A first inclined guide surface (12) is provided on the inner wall of the through hole (11) near the first spring (10). The vertical sliding hole (7) is connected to the vertical sliding hole (7). A vertical slider (13) is installed in the sliding hole (7). A top rod (14) is installed on the top of the vertical slider (13). The top rod (14) passes through the vertical sliding hole (7) and cooperates with the plastic part (5). A second spring (15) is installed on the outer wall of the top rod (14). The top of the second spring (15) contacts the moving template (4), and the bottom of the second spring (15) contacts the vertical slider (13). The bottom of the vertical slider (13) is inserted into the through hole (11). A second inclined guide surface (16) is installed on one side of the vertical slider (13). The second inclined guide surface (16) cooperates with the first inclined guide surface (12).

2. The ejection and demolding mechanism for injection molds without ejector plates as described in claim 1, characterized in that: The extrusion reset structure includes a wedge (17) set under the fixed template (3), the wedge (17) is fixed to the fixed block (18) by fasteners, the fixed block (18) is fixed to the fixed template (3) by fasteners, a third inclined guide surface (19) is set on one side of the wedge (17), and a fourth inclined guide surface (20) is set on one end of the transverse slider (9) near the wedge (17), the fourth inclined guide surface (20) cooperates with the third inclined guide surface (19).

3. The ejection and demolding mechanism for injection molds without ejector plates as described in claim 2, characterized in that: The wedge (17) is located on the upper part of the third inclined guide surface (19) and has a first straight surface (21). The transverse slider (9) is located on the upper part of the fourth inclined guide surface (20) and has a second straight surface (22). The second straight surface (22) cooperates with the first straight surface (21).

4. The ejection and demolding mechanism for injection molds without ejector plates as described in claim 1, characterized in that: The horizontal slider (9) has a positioning groove (23) below it, and the moving template (4) is provided with a positioning pin (24), the upper part of which cooperates with the positioning groove (23).

5. The ejection and demolding mechanism for injection molds without ejector plates as described in claim 1, characterized in that: The plug (8) is provided with a guide rod (25) on the side near the transverse slider (9), and the first spring (10) is sleeved on the outer wall of the guide rod (25).

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