Mould for high and thin ring-shaped cylinder product with large bottom angle fall and forming method thereof

Abstract

The invention relates to a mold, in particular to a mold containing a high and thin annular cylinder product with large bottom angle fall and a forming method of the mold, the mold comprises an upper mold and a lower mold, the upper mold and the lower mold are assembled to form a product cavity, and the mold further comprises an insert and a sleeve type insert which are fixed on the lower mold, a forming groove corresponding to the shape of the circular-ring-shaped cylindrical part is formed between the sleeve type insert and the insert, and the forming groove is communicated with the product cavity; the center ejector pin penetrates through the sleeve type insert and can slide relative to the sleeve type insert; and the at least one straight ejection unit penetrates through the lower die, and the ejection position of the straight ejection unit is in contact with the bone position of the circular-ring-shaped cylindrical part. The sleeve type insert and the insert are both fixed to the lower mold, and the arranged center ejector pin is located on the inner side of the sleeve type insert and does not make contact with the glue position face of the annular cylindrical part, so that the center ejector pin does not deform when subjected to injection molding pressure, and the injection molding quality is improved. And the problems that excessive glue exists at the bottom of the circular-ring-shaped cylindrical part, a formed thin edge exists or a formed product has flashes can be effectively solved.

Description

Technical Field

[0001] This invention relates to a mold, specifically a ring-shaped cylindrical product mold with a high and thin profile and a large bottom angle difference, and its forming method. Background Technology

[0002] Currently, there are some products such as Figure 9 As shown, due to the installation and strength requirements of the product, certain ribs or annular cylinders in the product may be made very high (more than 30mm). Although such products meet the functional requirements, they become very difficult to demold during the mold production process.

[0003] Although it is possible to use a straight push tube (ejector sleeve) and a center pin (ejector pin) to form and eject it, the annular cylinder of the product is very high (more than 30mm), and the bottom of the annular cylinder is a slope with a relatively large slope (about 20°).

[0004] When using a straight push tube (ejector sleeve) and a center pin (ejector sleeve needle) to form and eject the tube, since the center pin (ejector sleeve needle) is the core of a circular cylindrical shape, and the overmolding position is the circular cylindrical shape, the center pin (ejector sleeve needle) is as high as the circular cylindrical shape.

[0005] In existing molds, the center pin (ejector pin) is fixed, while the push tube (ejector) moves during product ejection. Because the bottom of the circular cylinder is sloped, the top surface of the push tube (ejector) needs to be sloped as well. When the mold injects plastic, under injection pressure, the sloped top surface of the push tube (ejector) and the center pin (ejector pin) experience uneven pressure, causing deformation. This widens the gap between the push tube (ejector) and the center pin (ejector pin) at the mating point, allowing plastic to escape into the gap. This results in excess plastic at the bottom of the circular cylinder, thin edges, or burrs on the molded product, failing to meet quality standards. If no ejection mechanism is installed here, the product's ribs and the excessive height of the circular cylinder make demolding inconvenient and prone to damage. Summary of the Invention

[0006] The purpose of this invention is to provide a high-profile, thin, and bottom-angle-difference circular cylindrical product mold and its forming method to solve the problems mentioned in the background art.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a mold for a high and thin annular cylindrical product with a large bottom angle difference, comprising an upper mold and a lower mold, wherein the upper mold and the lower mold are closed to form a product cavity, and further comprising: an insert and a sleeve-type insert fixed on the lower mold, wherein a forming groove corresponding to the shape of the annular cylindrical part is formed between the sleeve-type insert and the insert, and the forming groove communicates with the product cavity; a central ejector pin, which penetrates the sleeve-type insert and is capable of sliding relative to the sleeve-type insert; and at least one direct ejector unit, which penetrates the lower mold and whose ejector position contacts the rib of the annular cylindrical part.

[0008] As described above, the annular cylindrical product mold with a high and thin profile and a large bottom angle drop: the insert is wrapped around the outside of the sleeve-type insert.

[0009] The above-mentioned annular cylindrical product mold with a high and thin profile and a large bottom angle drop also includes a push mechanism, which is set on the lower mold and connected to the push plate. When the push plate moves up, it drives the push mechanism to perform the push operation.

[0010] As described above, the annular cylindrical product mold with a high and thin profile and a large bottom angle drop includes a straight ejector unit comprising a straight ejector block that slides on the lower mold and forms an ejector position, a straight ejector rod fixed on the straight ejector block, and the straight ejector rod passing through the lower mold and extending downward to connect with the ejector plate.

[0011] As described above, for a ring-shaped cylindrical product mold with a high and thin profile and a large bottom angle difference: the end of the central ejector pin away from the sleeve insert is connected to the push plate, and the central ejector pin, the straight ejector rod, and the push mechanism are synchronously driven by the push plate.

[0012] As described above, the mold for a high, thin, and large bottom angle drop of an annular cylindrical product is as follows: the central ejector pin is flush with the end face of the sleeve insert, and the inclination angle of the end face is adapted to the slope of the annular cylindrical part.

[0013] As described above, the annular cylindrical product mold with a high and thin profile and a large bottom angle drop has an exhaust groove on the insert for releasing the vacuum during the ejection stage.

[0014] A method for forming a ring-shaped cylindrical product with a high and thin profile and a large bottom angle difference, using the aforementioned ring-shaped cylindrical product mold with a high and thin profile and a large bottom angle difference, includes the following steps: S1. Mold closing: The upper mold and the lower mold are closed to form a product cavity that corresponds to the shape of the product. S2, Injection: Molten plastic is injected into the product cavity through the gate and then held under pressure to cool and solidify; S3. Mold Opening: Separate the upper mold from the lower mold, with the product inside the lower mold; S4. Ejection: The ejector plate moves upward to drive the central ejector pin, straight ejector rod and ejector mechanism to move upward synchronously. The central ejector pin passes through the annular cylindrical part and acts on the product end face connecting the annular cylindrical part. The straight ejector rod drives the straight ejector block, which acts on the rib of the annular cylindrical part. Together with the ejector mechanism, they push the product upward synchronously to eject the product out of the product cavity. The annular cylindrical part is ejected out of the forming groove. S5. The push plate resets, driving the central ejector pin, straight ejector rod, and push mechanism to reset synchronously, completing one-time molding.

[0015] As described above, for a ring-shaped cylindrical product mold with a high and thin profile and a large bottom angle difference: In step S4, the ejection speed is controlled in two stages. The first stage is a low-speed upward ejection to overcome the adhesion between the ring-shaped cylindrical part and the forming groove, and the second stage is a high-speed upward ejection for rapid demolding.

[0016] As described above, for a ring-shaped cylindrical product mold with a high and thin profile and a large bottom angle difference: In step S2, the gate is located opposite the rib of the ring-shaped cylindrical part, so that the melt flow direction is perpendicular to the ejection direction, thereby reducing molecular orientation stress.

[0017] Compared with the prior art, the beneficial effects of the present invention are: both the sleeve insert and the insert are fixed to the lower mold, and the central ejector pin is located inside the sleeve insert and does not come into contact with the glue surface of the annular cylindrical part, so that the central ejector pin will not deform when subjected to injection pressure, which can effectively eliminate the problems of excessive glue at the bottom of the annular cylindrical part, thin edges in the molding, or burrs in the molded product.

[0018] The set direct-push unit acts on the rib of the annular cylindrical part, and works with the central ejector pin on the end face of the product connecting the annular cylindrical part. This eliminates the problem of existing ejector pin assemblies being directly used on the inclined surface of the annular cylindrical part, which causes the product to be damaged due to slippage on the inclined surface, resulting in the annular cylindrical part being pushed and deformed. Attached Figure Description

[0019] Figure 1 A schematic diagram of the structure of a ring-shaped cylindrical product mold with a high and thin profile and a large bottom angle difference; Figure 2 for Figure 1 Cross-sectional view along the AA direction; Figure 3 for Figure 1 Cross-sectional view along the BB direction; Figure 4 A schematic diagram of the upper mold in a mold for a ring-shaped cylindrical product that is tall, thin, and has a large bottom angle difference; Figure 5 A schematic diagram of the lower mold in a mold for a ring-shaped cylindrical product that is tall, thin, and has a large bottom angle difference; Figure 6 for Figure 3 Enlarged view of the structure at point C; Figure 7 This is a structural diagram of the central ejector pin, sleeve insert, insert and direct ejector unit in a mold for a high, thin, and large-angled annular cylindrical product; Figure 8 This is a structural diagram of the central ejector pin, sleeve insert, insert and direct ejector unit at another angle in a mold for a high, thin, and large-angled annular cylindrical product; Figure 9 This is a schematic diagram of the structure of a ring-shaped cylindrical component in a mold for a ring-shaped cylindrical product that is tall, thin, and has a large bottom angle difference.

[0020] In the diagram: 1-Upper mold, 2-Lower mold, 3-Push mechanism, 4-Straight ejector rod, 5-Straight ejector block, 6-Center ejector pin, 7-Sleeve insert, 8-Insert, 9-Forming groove, 10-Circular cylindrical part, 1001-Circular cylindrical part rib. Detailed Implementation

[0021] Various exemplary embodiments, features, and aspects of this application will now be described in detail with reference to the accompanying drawings. The same reference numerals in the drawings denote elements that have the same or similar functions. Although various aspects of the embodiments are shown in the drawings, they are not necessarily drawn to scale unless specifically indicated otherwise.

[0022] The term “exemplary” as used herein means “serving as an example, embodiment, or illustration.” Any embodiment illustrated herein as “exemplary” is not necessarily to be construed as superior to or better than other embodiments.

[0023] Furthermore, to better illustrate this application, numerous specific details are provided in the following detailed embodiments. Those skilled in the art should understand that this application can be implemented even without certain specific details. In some instances, methods, means, and elements well-known to those skilled in the art have not been described in detail in order to highlight the main points of this application.

[0024] Please see Figures 1-9In this embodiment of the invention, a mold for a high, thin, and large-angle-difference annular cylindrical product includes an upper mold 1 and a lower mold 2. After the upper mold 1 and the lower mold 2 are closed, a product cavity is formed. The mold also includes: an insert 8 and a sleeve insert 7 fixed on the lower mold 2. A forming groove 9 corresponding to the shape of the annular cylindrical part 10 is formed between the sleeve insert 7 and the insert 8, and the forming groove 9 communicates with the product cavity. The insert 8 wraps around the outside of the sleeve insert 7, and the insert 8 is provided with an exhaust groove (not shown in the figure) for venting vacuum during the ejection stage; a central ejector pin 6, which penetrates the sleeve insert 7 and can slide relative to the sleeve insert 7; and at least one straight ejector unit, which penetrates the lower mold 2 and whose ejector position contacts the rib position 1001 of the annular cylindrical part.

[0025] In this embodiment, both the sleeve insert 7 and the insert 8 are fixed to the lower mold 2. The central ejector pin 6 is located inside the sleeve insert 7 and does not contact the glue surface of the annular cylindrical part 10. This ensures that the central ejector pin 6 will not deform under injection pressure, effectively eliminating the problems of excess glue at the bottom of the annular cylindrical part 10, thin edges in the molding, or burrs on the molded product.

[0026] Secondly, the set direct push unit acts on the rib position 1001 of the annular cylindrical part, and works with the central push pin 6 to act on the product end face connecting the annular cylindrical part 10, so as to eliminate the problem that the existing push pin assembly is directly used with the inclined surface of the annular cylindrical part 10, which causes the product to be damaged due to slippage on the inclined surface, resulting in the annular cylindrical part 10 being pushed and deformed.

[0027] Furthermore, the aforementioned annular cylindrical product mold with a high and thin profile and a large bottom angle drop also includes a push mechanism 3, which is set on the lower mold 2 and connected to the push plate. When the push plate moves up, it drives the push mechanism 3 to perform a push operation. When the push plate moves up, it can stably and effectively drive the push mechanism 3 to perform a push operation.

[0028] It should be noted that the push mechanism 3 mentioned here is an existing mold push mechanism used for demolding and is a conventional technical application. This embodiment will not elaborate on it further.

[0029] The aforementioned straight ejector unit includes a straight ejector block 5 that slides on the lower mold 2 and forms an ejector position. A straight ejector rod 4 is fixed on the straight ejector block 5. The straight ejector rod 4 passes through the lower mold 2 and extends downward to connect with the ejector plate. The end of the central ejector pin 6 away from the sleeve insert 7 is connected to the ejector plate. The central ejector pin 6, the straight ejector rod 4, and the ejector mechanism 3 are synchronously driven by the ejector plate, ensuring that the straight ejector block 5, the central ejector pin 6, and the ejector mechanism 3 can move upward synchronously during the ejection process. This provides a stable ejection force for the product, the annular cylindrical part 10, and the annular cylindrical part rib 1001, ensuring the coordination and consistency of each component during the ejection process. This effectively eliminates molding defects caused by asynchronous ejection. At the same time, the straight ejector rod 4 passes through the lower mold 2 and connects to the ejector plate, allowing the ejection force to be directly and effectively transmitted to the straight ejector block 5, further improving the stability and reliability of the ejection process.

[0030] Furthermore, the central ejector pin 6 is flush with the end face of the sleeve-type insert 7, and the inclination angle of the end face matches the slope of the inclined surface of the annular cylindrical part 10. This allows the central ejector pin 6 to perfectly fit the inclined surface of the product during the pushing process, effectively avoiding stress concentration caused by uneven contact surfaces, thereby further improving the stability of the pushing and the product quality.

[0031] As another embodiment of the present invention, a method for forming a ring-shaped cylindrical product with a high and thin profile and a large bottom angle difference is also proposed. This method uses the aforementioned mold for a ring-shaped cylindrical product with a high and thin profile and a large bottom angle difference, and includes the following steps: S1. Mold closing: The upper mold 1 and the lower mold 2 are closed to form a product cavity corresponding to the shape of the product. S2, Injection: Molten plastic is injected into the product cavity through the gate and then held under pressure to cool and solidify; S3. Mold opening: Separate the upper mold 1 from the lower mold 2, and the product is placed in the lower mold 2; S4, Ejection: The ejector plate moves upward to drive the central ejector pin 6, the straight ejector rod 4 and the ejector mechanism 3 to move upward synchronously. The central ejector pin 6 passes through the annular cylindrical part 10 and acts on the product end face connecting the annular cylindrical part 10. The straight ejector rod 4 drives the straight ejector block 5, which acts on the rib position 1001 of the annular cylindrical part. Together with the ejector mechanism 3, the product is pushed upward synchronously to eject the product out of the product cavity. The annular cylindrical part 10 is ejected out of the forming groove 9. S5. The push plate resets, driving the central ejector pin 6, the straight ejector rod 4, and the push mechanism 3 to reset synchronously, completing one-time molding.

[0032] In step S4, the ejection speed is controlled in two stages. The first stage is a low-speed upward ejection to overcome the adhesion between the annular cylindrical part 10 and the forming groove 9. The second stage is a high-speed upward ejection for rapid demolding. Preferably, the low speed in the first stage is 0.5-2 mm / s, and the high speed in the second stage is 5-15 mm / s.

[0033] In step S2, the gate is located opposite the annular cylindrical part rib 1001, so that the melt flow direction is perpendicular to the ejection direction, thereby reducing molecular orientation stress.

[0034] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0035] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A mold for a high and thin annular cylindrical product with a large bottom angle difference, comprising an upper mold (1) and a lower mold (2), wherein the upper mold (1) and the lower mold (2) are closed to form a product cavity, characterized in that, Also includes: An insert (8) and a sleeve insert (7) are fixed on the lower mold (2). A forming groove (9) corresponding to the shape of the annular cylindrical part (10) is formed between the sleeve insert (7) and the insert (8), and the forming groove (9) communicates with the product cavity; a central ejector pin (6) passes through the sleeve insert (7) and can slide relative to the sleeve insert (7); at least one straight ejector unit passes through the lower mold (2) and the ejector position of the straight ejector unit contacts the annular cylindrical part rib (1001).

2. The annular cylindrical product mold with a high and thin profile and a large bottom angle difference according to claim 1, characterized in that, The insert (8) is wrapped around the outside of the sleeve insert (7).

3. The annular cylindrical product mold with a high and thin profile and a large bottom angle drop as described in claim 1, characterized in that... It also includes a push mechanism (3), which is set on the lower mold (2) and connected to the push plate. When the push plate moves up, it drives the push mechanism (3) to perform the push operation.

4. The annular cylindrical product mold with a high and thin profile and a large bottom angle drop according to claim 3, characterized in that, The straight ejector unit includes a straight ejector block (5) that slides on the lower mold (2) and forms a push position. A straight ejector rod (4) is fixed on the straight ejector block (5). The straight ejector rod (4) passes through the lower mold (2) and extends downward to connect with the push plate.

5. A ring-shaped cylindrical product mold with a high and thin profile and a large bottom angle drop, as described in claim 4, is characterized in that... The end of the central ejector pin (6) away from the sleeve insert (7) is connected to the push plate. The central ejector pin (6), the straight push rod (4) and the push mechanism (3) are driven synchronously by the push plate.

6. A mold for a high-height, thin, and large-angle-difference annular cylindrical product as described in claim 1, characterized in that, The central pin (6) is flush with the end face of the sleeve insert (7), and the inclination angle of the end face is adapted to the slope of the inclined surface of the annular cylindrical part (10).

7. A ring-shaped cylindrical product mold with a high and thin profile and a large bottom angle difference according to claim 1, characterized in that, The insert (8) is provided with an exhaust groove for venting the vacuum during the ejection stage.

8. A method for forming a ring-shaped cylindrical product that is tall, thin, and has a large bottom angle difference, characterized in that... The method of using the annular cylindrical product mold as described in claim 5, which is tall, thin, and has a large bottom angle difference, includes the following steps: S1. Mold closing: The upper mold (1) and the lower mold (2) are closed to form a product cavity corresponding to the product shape; S2, Injection: Molten plastic is injected into the product cavity through the gate and then held under pressure to cool and solidify; S3, Mold opening: Separate the upper mold (1) from the lower mold (2), and the product is placed in the lower mold (2); S4, Ejection: The push plate moves upward to drive the central ejector pin (6), the straight push rod (4) and the push mechanism (3) to move upward synchronously. The central ejector pin (6) passes through the annular cylindrical part (10) and acts on the product end face connecting the annular cylindrical part (10). The straight push rod (4) drives the straight push block (5). The straight push block (5) acts on the rib position (1001) of the annular cylindrical part. Together with the push mechanism (3), the product moves upward synchronously to eject the product out of the product cavity. The annular cylindrical part (10) is ejected out of the molding groove (9). S5. The push plate is reset, which drives the central ejector pin (6), the straight ejector rod (4) and the push mechanism (3) to reset synchronously, completing one-time molding.

9. The method for forming a ring-shaped cylindrical product with a high and thin profile and a large bottom angle difference according to claim 8, characterized in that, In step S4, the ejection speed is controlled in two stages. The first stage is low-speed ejection to overcome the adhesion between the annular cylindrical part (10) and the forming groove (9). The second stage is high-speed ejection to quickly demold.

10. The method for forming a high, thin, and large-angle-difference annular cylindrical product according to claim 8, characterized in that, In step S2, the gate is located opposite the annular cylindrical part rib (1001), so that the melt flow direction is perpendicular to the ejection direction, thereby reducing molecular orientation stress.

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