Local efficient cooling of injection molds

Abstract

The present application relates to the field of injection mold cooling technology, and in particular to a local efficient cooling injection mold. The mold includes a template and a heat conductive block, wherein the template is provided with a molding surface to form a molding cavity in the mold closing state; at least one template is provided with an embedding groove to embed a heat conductive block with a high thermal conductivity coefficient. In addition, it also includes a baffle, an integral flow channel and a local flow channel, and effective cooling of key parts is achieved by controlling the flow path and speed of the cooling medium. The present application achieves the technical effect of improving cooling efficiency, shortening production cycle and ensuring the quality of injection molded products.

Description

Technical Field

[0001] The present application relates to the technical field of injection mold cooling, and in particular to a local high-efficiency cooling injection mold. Background Art

[0002] Injection molds are an indispensable and important tool in the modern plastic processing industry and are widely used in the production process of various plastic products. As the market's requirements for product performance and quality continue to increase, the injection molding process is also constantly improving and improving. However, in actual applications, due to the design complexity and material properties of different products, there are many challenges in the injection molding process, especially when dealing with products with uneven thickness, the heat dissipation problem is particularly prominent.

[0003] In existing injection molding technology, in order to deal with the problem of uneven heat dissipation, the following methods are usually used: first, by optimizing the overall cooling system of the mold, such as increasing the number and distribution density of cooling water channels; second, using mold materials with high thermal conductivity to improve the thermal conductivity of the entire mold; third, adjusting injection molding parameters, such as reducing injection speed and pressure, and extending the holding time to ensure that the molten plastic can be fully cooled and solidified. Although these methods can improve the heat dissipation effect to a certain extent, they still cannot completely solve the heat dissipation problem in areas with uneven thickness.

[0004] Although the above methods have alleviated the problem of uneven heat dissipation to a certain extent, there are still obvious deficiencies in actual operation. Especially for thicker parts, traditional cooling methods often fail to achieve the ideal cooling effect, resulting in the failure of the part to solidify in time and the possibility of incomplete solidification, which in turn affects the quality and stability of the final product. Therefore, how to effectively improve the local cooling efficiency, especially to achieve rapid and uniform cooling in molds with uneven thickness, has become a key technical problem that needs to be solved urgently. Summary of the invention

[0005] In order to achieve uniform cooling of thin walls and thick walls, the present application provides a local efficient cooling injection mold.

[0006] The local efficient cooling injection mold provided by the present application adopts the following technical solution:

[0007] A local high-efficiency cooling injection mold, comprising a template and a heat-conducting block,

[0008] The template is provided with two, and the template is provided with a molding surface,

[0009] When the two templates are in a mold-clamping state, the two molding surfaces enclose a molding cavity.

[0010] At least one of the templates is provided with an embedding groove, wherein the embedding groove is located at the molding surface.

[0011] The heat-conducting block is embedded in the embedding groove, and the thermal conductivity of the heat-conducting block is greater than the thermal conductivity of the template.

[0012] By adopting the above technical solution, when the wall thickness of the injection molded product is uneven, a groove is set at the location of the molding cavity corresponding to the location of the larger wall thickness, and a heat conduction block is installed. During the cooling process of the injection molded product, the location with smaller wall thickness is cooled by heat conduction of the template, and the location with larger wall thickness is cooled by heat conduction of the heat conduction block. The thermal conductivity of the heat conduction block is greater than the thermal conductivity of the template, so that the cooling of the location with smaller wall thickness and the location with larger wall thickness can be completed synchronously within equal or similar time, and the cooling molding of the injection molded product is completed.

[0013] Preferably, a baffle is included,

[0014] The template is provided with an overall flow channel and a local flow channel.

[0015] The integral flow channel is used to cool the template.

[0016] An inlet and an outlet are provided at one end of the local flow channel, and both the inlet and the outlet are connected to the overall flow channel. The inlet is used for the cooling medium to flow into the local flow channel, and the outlet is used for the cooling medium to flow out of the local flow channel.

[0017] The baffle is embedded in the local flow channel, the baffle is located between the inlet and the outlet, and the edge of the baffle is used to touch the inner wall of the local flow channel.

[0018] The heat conducting block is provided with a cooling groove, and the cooling groove is connected to the other end of the local flow channel.

[0019] By adopting the above technical solution, the structure of the local flow channel and the cooling groove is simple and easy to process.

[0020] Preferably, one end of the baffle is embedded in the local flow channel.

[0021] The other end of the baffle is inserted into the cooling groove, and the other end of the baffle is provided with a notch.

[0022] By adopting the above technical solution, the cooling medium at the bottom of the cooling groove is kept flowing, so that the heat conductive block is used to efficiently cool the thicker wall.

[0023] Preferably, the thermal conductivity of the baffle is smaller than the thermal conductivity of the template.

[0024] By adopting the above technical solution, the temperature of the cooling medium flowing to the outlet is higher than the cooling medium flowing into the inlet. The thermal conductivity of the baffle is small, which reduces the heat exchange of the cooling medium on both sides of the baffle, which is conducive to maintaining the low temperature of the cooling medium at the inlet, so as to achieve efficient cooling of the thick wall by using the heat conduction block.

[0025] Preferably, the flow rate of the cooling medium on one side of the substrate toward the inlet is smaller than the flow rate of the cooling medium on the other side of the substrate.

[0026] By adopting the above technical solution, the temperature of the cooling medium flowing to the outlet is higher than the cooling medium flowing into the inlet. The cooling medium flow rate on the side of the substrate toward the outlet is relatively large, which reduces the contact time between the high-temperature cooling medium and the baffle, reduces the heat exchange of the cooling medium on both sides of the baffle, and is conducive to maintaining the low temperature of the cooling medium at the inlet, so as to achieve efficient cooling of the thicker wall by using the heat conduction block.

[0027] Specifically, when the cooling medium is introduced and the cooling medium contacts the heat conductive block, the temperature difference between the cooling medium and the heat conductive block is the largest, the heat exchange efficiency between the two is the highest, the temperature rise of the cooling medium is the largest, and the temperature drop and reset of the heat conductive block is the largest. The cooling medium with the highest temperature flows quickly to the outlet, reducing the contact time between the cooling medium with the highest temperature and the baffle, and reducing the heat exchange between the two. Subsequently, the temperature difference between the cooling medium and the heat conductive block decreases, the heat exchange efficiency between the two decreases, and the temperature rise of the cooling medium decreases.

[0028] Preferably, the baffle comprises a substrate and an elastic membrane.

[0029] The elastic film covers the surface of the substrate facing the outlet, and a cavity enclosed by the elastic film and the substrate is filled with gas.

[0030] By adopting the above technical solution, the cooling medium contacts the elastic membrane, the thermal conductivity of the gas is poor, and the heat exchange between the cooling medium and the baffle is reduced.

[0031] The cooling medium that is heated by flowing through the heat conducting block causes the gas in the elastic membrane to expand due to heat, and the channel cross-sectional area of ​​the substrate toward the outlet side is reduced, thereby accelerating the flow rate of the heated cooling medium.

[0032] Preferably, two elastic membranes are provided, and the substrate is located between the two elastic membranes.

[0033] By adopting the above technical solution, the cooling medium contacts the elastic membrane, the thermal conductivity of the gas is poor, the heat exchange between the cooling medium and the baffle is reduced, and the heat exchange of the cooling medium on both sides of the baffle is reduced.

[0034] The temperature of the cooling medium on the side of the substrate facing the outlet is higher, and the gas expansion volume on the side of the substrate facing the outlet is larger, so that a larger cooling medium flow rate on the side of the substrate facing the outlet is achieved.

[0035] Preferably, the heat conductive block comprises a beryllium bronze block.

[0036] By adopting the above technical solution, the thermal conductivity of the heat-conducting block is greater than the thermal conductivity of the template.

[0037] In summary, the present application includes at least one of the following beneficial technical effects:

[0038] 1. When the wall thickness of the injection molded product is uneven, an embedding groove is set at the position of the molding cavity corresponding to the position of the larger wall thickness, and a heat conduction block is installed; during the cooling process of the injection molded product, the smaller wall thickness is cooled by heat conduction of the template, and the larger wall thickness is cooled by heat conduction of the heat conduction block; the thermal conductivity of the heat conduction block is greater than the thermal conductivity of the template, so that the cooling of the smaller wall thickness and the larger wall thickness can be completed synchronously within equal or similar time, and the injection molded product is cooled and molded;

[0039] 2. Use the baffle to separate the local flow channel into two parts, so that the cooling medium can flow into and out of the cooling groove, making the structure of the local flow channel and cooling groove simple and easy to process;

[0040] 3. The temperature of the cooling medium flowing to the outlet is higher than that of the cooling medium flowing into the inlet; the thermal conductivity of the baffle is small, and the cooling medium flow rate on the side of the substrate toward the outlet is large, which reduces the contact time between the high-temperature cooling medium and the baffle, and reduces the heat exchange of the cooling medium on both sides of the baffle, which is conducive to maintaining the low temperature of the cooling medium at the inlet, so as to achieve efficient cooling of the thicker wall by using the heat conduction block. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 It is a schematic diagram of a local efficient cooling injection mold.

[0042] Figure 2 It is a cross-sectional schematic diagram of a local efficient cooling injection mold.

[0043] Figure 3 yes Figure 2 Enlarged view of point A in the middle.

[0044] Explanation of the reference numerals: 1. Template; 11. Molding surface; 12. Molding cavity; 13. Embedded groove; 14. Overall flow channel; 15. Local flow channel; 16. Inlet; 17. Outlet; 2. Heat transfer block; 21. Cooling groove; 3. Baffle; 31. Notch; 32. Substrate; 33. Elastic membrane. DETAILED DESCRIPTION

[0045] The present application is further described in detail below in conjunction with the accompanying drawings.

[0046] Reference Figure 1 , an embodiment of the present application discloses a local efficient cooling injection mold, including a template 1.

[0047] Reference Figure 2 and Figure 3 The template 1 is provided with two, and the template 1 is provided with a molding surface 11. When the two templates 1 are in a mold-closing state, the two molding surfaces 11 enclose a molding cavity 12.

[0048] The local efficient cooling injection mold further comprises a heat conducting block 2 .

[0049] The thermal conductivity of the heat-conducting block 2 is greater than the thermal conductivity of the template 1. For example, the heat-conducting block 2 includes a beryllium copper block.

[0050] At least one template 1 is provided with an embedding groove 13 , and the embedding groove 13 is located at the molding surface 11 . The heat conducting block 2 is embedded in the embedding groove 13 .

[0051] The template 1 is provided with an overall flow channel 14 and a local flow channel 15 .

[0052] The integral flow channel 14 is used for cooling medium to flow so as to cool the template 1. The cooling medium is usually a coolant.

[0053] An inlet 16 and an outlet 17 are provided at one end of the local flow channel 15, and both the inlet 16 and the outlet 17 are connected to the overall flow channel 14. The inlet 16 is used for the cooling medium to flow into the local flow channel 15, and the outlet 17 is used for the cooling medium to flow out of the local flow channel 15.

[0054] The heat conducting block 2 is provided with a cooling groove 21 , and the cooling groove 21 is connected to the other end of the local flow channel 15 .

[0055] The local efficient cooling injection mold further comprises a baffle 3 .

[0056] The baffle 3 is embedded in the local flow channel 15, and the baffle 3 is located between the inlet 16 and the outlet 17. The edge of the baffle 3 is used to touch the inner wall of the local flow channel 15, so that the cooling medium on both sides of the baffle 3 flows in opposite directions.

[0057] In one embodiment, the baffles 3 are all located in the local flow channel 15 .

[0058] In the accompanying drawings: one end of the baffle 3 is embedded in the local flow channel 15, and the other end of the baffle 3 is inserted into the cooling groove 21; at the same time, the other end of the baffle 3 is provided with a notch 31; when the other end of the baffle 3 abuts against the bottom of the cooling groove 21: the notch 31 is used for the flow of cooling medium.

[0059] In the process of cooling medium flowing to the heat transfer block 2 , in order to minimize the temperature rise of the cooling medium: the thermal conductivity of the baffle 3 is smaller than the thermal conductivity of the template 1 ; the cooling medium flow rate on the side of the substrate 32 toward the inlet 16 is smaller than the cooling medium flow rate on the other side of the substrate 32 .

[0060] Specifically, the baffle 3 includes a base plate 32 and an elastic membrane 33 .

[0061] The elastic membrane 33 covers the surface of the substrate 32 facing the outlet 17 , and the cavity enclosed by the elastic membrane 33 and the substrate 32 is filled with gas.

[0062] The cooling medium directly contacts the elastic membrane 33, and the thermal conductivity of the gas is poor, which reduces the heat exchange between the cooling medium and the baffle 3, and reduces the heat exchange of the cooling medium on both sides of the baffle 3. The cooling medium that flows through the heat conductive block 2 and heats up causes the gas in the elastic membrane 33 to expand due to heat, and the channel cross-sectional area of ​​the substrate 32 toward the outlet 17 is reduced, which accelerates the flow rate of the heated cooling medium.

[0063] In the drawings, two elastic membranes 33 are provided, and the substrate 32 is located between the two elastic membranes 33 .

[0064] The temperature of the cooling medium on the side of the substrate 32 facing the outlet 17 is higher, so the gas expansion volume on the side of the substrate 32 facing the outlet 17 is larger, and the channel cross-sectional area on the side of the substrate 32 facing the outlet 17 is smaller than the channel cross-sectional area on the side of the substrate 32 facing the inlet 16, thereby achieving a higher cooling medium flow rate on the side of the substrate 32 facing the outlet 17.

[0065] The implementation principle of a local efficient cooling injection mold in the embodiment of the present application is as follows: when the wall thickness of the injection molded product is uneven, a groove 13 is set at the molding cavity 12 corresponding to the position with larger wall thickness, and a heat conductive block 2 is installed. During the cooling process of the injection molded product, the area with smaller wall thickness is cooled by heat conduction of the template 1, and the area with larger wall thickness is cooled by heat conduction of the heat conductive block 2. The thermal conductivity of the heat conductive block 2 is greater than that of the template 1, so that the cooling of the area with smaller wall thickness and the area with larger wall thickness can be completed synchronously within equal or similar time, and the injection molded product can be cooled and molded.

[0066] The temperature of the cooling medium flowing to the outlet 17 is higher than that of the cooling medium flowing into the inlet 16. The thermal conductivity of the baffle 3 is relatively small, and the cooling medium flow rate on the side of the substrate 32 facing the outlet 17 is relatively large, which reduces the contact time between the high-temperature cooling medium and the baffle 3, reduces the heat exchange of the cooling medium on both sides of the baffle 3, and helps the cooling medium at the inlet 16 to maintain a low temperature, so as to achieve efficient cooling of the thicker wall by using the heat conductive block 2.

[0067] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A local efficient cooling injection mold, characterized in that: It comprises a template (1), a heat conducting block (2) and a baffle (3), The template (1) is provided with two, and the template (1) is provided with a molding surface (11). When the two templates (1) are in a mold-clamping state, the two molding surfaces (11) enclose a molding cavity (12). At least one of the templates (1) is provided with an embedding groove (13), wherein the embedding groove (13) is located on the molding surface (11). The heat-conducting block (2) is embedded in the embedding groove (13), and the thermal conductivity of the heat-conducting block (2) is greater than the thermal conductivity of the template (1); The template (1) is provided with an overall flow channel (14) and a local flow channel (15). The integral flow channel (14) is used to cool the template (1). An inlet (16) and an outlet (17) are provided at one end of the local flow channel (15), and the inlet (16) and the outlet (17) are both connected to the overall flow channel (14); the inlet (16) is used for allowing the cooling medium to flow into the local flow channel (15), and the outlet (17) is used for allowing the cooling medium to flow out of the local flow channel (15). The baffle (3) is embedded in the local flow channel (15), the baffle (3) is located between the inlet (16) and the outlet (17), and the edge of the baffle (3) is used to touch the inner wall of the local flow channel (15). The heat conducting block (2) is provided with a cooling groove (21), and the cooling groove (21) is connected to the other end of the local flow channel (15); The baffle (3) comprises a base plate (32) and an elastic membrane (33). The elastic membrane (33) covers the surface of the substrate (32) facing the outlet (17), and a cavity enclosed by the elastic membrane (33) and the substrate (32) is filled with gas.

2. The local efficient cooling injection mold according to claim 1, characterized in that: One end of the baffle (3) is embedded in the local flow channel (15). The other end of the baffle (3) is inserted into the cooling groove (21), and the other end of the baffle (3) is provided with a notch (31).

3. The local efficient cooling injection mold according to claim 1, characterized in that: The thermal conductivity of the baffle (3) is smaller than the thermal conductivity of the template (1).

4. The local efficient cooling injection mold according to claim 1, characterized in that: The flow rate of the cooling medium on the side of the baffle (3) facing the inlet (16) is smaller than the flow rate of the cooling medium on the other side of the baffle (3).

5. The local efficient cooling injection mold according to claim 1, characterized in that: Two elastic membranes (33) are provided, and the base plate (32) is located between the two elastic membranes (33).

6. The local efficient cooling injection mold according to claim 1, characterized in that: The heat conducting block (2) comprises a beryllium bronze block.

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