Injection molded in-mold cut structure

Abstract

The utility model relates to injection mould technology field, concretely relates to a kind of injection mould inner cut structure, including the injection cavity formed by the upper die and lower die mould, injection cavity includes the forming cavity and runner being communicated, and barrier, barrier has the thimble moving towards forming cavity and runner communication place.This utility model adds the barrier with thimble in injection mould, can when the injection cavity pressure-keeping end, material at this time is still in plastic state, drive thimble to move to the junction of forming cavity and runner, physically cut off the channel of both.Further in subsequent cooling procedure, the product in forming cavity and the surplus material in runner will be separated naturally, cut procedure is saved.

Description

Technical Field

[0001] This utility model relates to the field of injection mold technology, and in particular to an internal slit structure for injection molds. Background Technology

[0002] In the injection molding process of automotive parts, molten material needs to enter the molding cavity through the mold runner, cool and solidify to form the product. Upon demolding, excess material that has cooled and solidified simultaneously within the runner is attached to the product. Traditionally, this excess material is removed using a blade. However, this method easily causes scratches on the product surface, leading to additional repair processes in the production process. Utility Model Content

[0003] The technical problem to be solved by this utility model is to provide an internal cutting structure for injection molds to avoid the residual material from being integrally formed with the product, thereby eliminating the need for additional repair processes.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is as follows: an injection mold internal cutting structure, including an injection cavity formed by the closing of an upper mold and a lower mold, wherein the injection cavity includes a connected molding cavity and a runner. A barrier member having an ejector pin that moves toward the connection between the molding cavity and the flow channel.

[0005] Furthermore, the barrier also includes a push plate and a limiting plate spaced apart along the moving direction of the ejector pin; the ejector pin is connected to the push plate.

[0006] Furthermore, the distance between the push plate and the limiting plate is 1mm to 2mm.

[0007] Furthermore, an elastic element is provided between the push plate and the limiting plate.

[0008] Furthermore, the ejector pin includes a reinforcing portion and a blocking portion, wherein the cross-sectional area of ​​the reinforcing portion is larger than the cross-sectional area of ​​the blocking portion.

[0009] Furthermore, the length of the blocking portion is 80mm to 100mm.

[0010] Furthermore, the reinforcing part is cylindrical or rectangular, and the blocking part is rectangular.

[0011] Furthermore, the tip of the ejector pin is needle-shaped.

[0012] Furthermore, a gate is provided at the connection between the molding cavity and the runner, and the flow area of ​​the gate gradually decreases toward the molding cavity.

[0013] Furthermore, the barrier is disposed in the lower mold, and the lower mold is provided with an ejector pin hole located below the barrier.

[0014] The beneficial effects of this invention are as follows: By adding a barrier component with ejector pins inside the injection mold, when the material is still in a plastic state at the end of the pressure holding process in the injection cavity, the ejector pins are driven to move to the connection between the molding cavity and the runner, physically cutting off the passage between the two. Consequently, in the subsequent cooling process, the product in the molding cavity and the remaining material in the runner will naturally separate, eliminating the need for a cutting process. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the internal slit structure of an injection mold proposed in this utility model; Figure 2 This is a schematic diagram of an injection mold cavity structure with an internal tangential structure proposed in this utility model; Figure 3 for Figure 2 Enlarged view of part A of an internal tangential structure of an injection mold; Figure 4 This is a schematic diagram of an ejector pin structure with an internal tangential structure for injection molds, as proposed in this utility model. Figure 5 This is a schematic diagram of the mold closing surface structure of the upper mold with an internal tangential structure proposed in this utility model; Figure 6 This is a schematic diagram of the mold closing surface structure of the lower mold of the injection mold with an internal tangential structure proposed in this utility model.

[0016] Label Explanation: 1. Injection cavity; 11. Molding cavity; 12. Runner; 2. Barrier component; 21. Ejector pin; 211. Reinforcing part; 212. Blocking part; 22. Push plate; 23. Limiting plate; 3. Elastic components; 4. Gate; 5. Guide tilt column; 6. Slider; 61. Mold core; 62. Guide hole; 8. Upper mold; 9. Lower mold; 91. Ejector pin hole. Detailed Implementation

[0017] To explain in detail the technical content, objectives, and effects of this utility model, the following description is provided in conjunction with the embodiments and accompanying drawings.

[0018] Please refer to Figure 1 and Figure 2 As shown, the present invention provides an injection mold internal cutting structure, including an injection cavity 1 formed by the closing of an upper mold 8 and a lower mold 9. The injection cavity 1 includes a connected molding cavity 11 and a runner 12, as well as a barrier member 2. The barrier member 2 has an ejector pin 21 that moves toward the connection between the molding cavity 11 and the runner 12.

[0019] Working principle: When the pressure holding in injection cavity 1 ends, the material is still in a plastic state. The ejector pin 21 is driven to move to the connection between the molding cavity 11 and the runner 12, physically cutting off the channel between the two. Subsequently, in the cooling process, the product in the molding cavity 11 and the remaining material in the runner 12 will naturally separate, eliminating the need for a cutting process.

[0020] It is worth noting that the moving speed of ejector pin 21 is 20% to 30% of the moving speed of ejector roller during the demolding process of injection molding machine.

[0021] Preferably, the tip of the ejector pin 21 is needle-shaped. The needle-shaped tip can guide the material to flow towards the molding cavity 11 and / or the flow channel 12, thereby better cutting off the material.

[0022] In some implementations, please refer to Figure 3 As shown, the barrier 2 also includes a push plate 22 and a limiting plate 23 spaced apart along the moving direction of the ejector pin 21; the ejector pin 21 is connected to the push plate 22. During the process of the push plate 22 driving the ejector pin 21 to cut off the connection between the molding cavity 11 and the flow channel 12, the limiting plate 23 is used to limit the pushing stroke of the push plate 22 to prevent the ejector pin 21 from moving beyond its stroke.

[0023] It is worth noting that, please refer to Figure 2 and Figure 3 As shown, the distance between the push plate 22 and the limiting plate 23 is B, which is 1mm to 2mm. The value of B is determined by the thickness of the connection between the molding cavity 11 and the flow channel 12. Generally, the value of B is equal to the thickness of the connection between the molding cavity 11 and the flow channel 12. Of course, the value of B can also be slightly greater than the thickness of the connection between the molding cavity 11 and the flow channel 12 by 0.1mm.

[0024] In some implementations, please refer to Figure 3 As shown, an elastic element 3 is provided between the push plate 22 and the limiting plate 23. After the upper mold 8 and the lower mold 9 are separated, the push plate 22 can be automatically driven to reset by the elastic element 3.

[0025] It is worth noting that the elastic element 3 can be a compression spring, gas spring, or other device that can generate elastic force to drive the push plate 22 to move.

[0026] In some implementations, please refer to Figure 4 As shown, the ejector pin 21 includes a reinforcing portion 211 and a blocking portion 212. The cross-sectional area of ​​the reinforcing portion 211 is larger than that of the blocking portion 212. The reinforcing portion 211 enhances the overall strength of the ejector pin 21 to prevent deformation or breakage of the ejector pin 21, while the blocking portion 212 severs the connection between the molding cavity 11 and the flow channel 12.

[0027] It is worth noting that the reinforcing part 211 is cylindrical or rectangular, and the blocking part 212 is rectangular.

[0028] In some implementations, please refer to Figure 4 As shown, the length of the blocking portion 212 is C, which is 80mm to 100mm. C includes, but is not limited to, 80mm, 85mm, 95mm, and 100mm. By limiting the length of the blocking portion 212, it is ensured that the blocking portion 212 has sufficient length to cut off the connection between the molding cavity 11 and the flow channel 12.

[0029] In some implementations, please refer to Figure 2 As shown, a gate 4 is provided at the connection between the molding cavity 11 and the runner 12, and the flow area of ​​the gate 4 gradually decreases towards the molding cavity 11. The gate 4 can not only increase the flow velocity of the material flowing into the molding cavity 11, but also reduce the area of ​​the ejector pin 21 that cuts off the molding cavity 11 and the runner 12.

[0030] In some implementations, please refer to Figure 3 As shown, the barrier 2 is disposed in the lower mold 9, and the lower mold 9 has an ejector pin hole 91 located below the barrier 2. The ejector pin of the injection molding machine can lift the barrier 2 through the ejector pin hole 91, thereby driving the ejector pin 21 to cut off the connection between the molding cavity 11 and the runner 12.

[0031] Example 1 An injection mold internal cutting structure, please refer to Figures 1 to 3 As shown, the injection cavity 1 is formed by the closing of the upper mold 8 and the lower mold 9. The injection cavity 1 includes a molding cavity 11, a gate 4, and a runner 12 connected in sequence, as well as a barrier 2. The barrier 2 has an ejector pin 21 that moves toward the connection between the molding cavity 11 and the runner 12, and a push plate 22 and a limiting plate 23 spaced apart along the moving direction of the ejector pin 21. The ejector pin 21 is connected to the push plate 22, and the distance between the push plate 22 and the limiting plate 23 is 2mm. A compression spring is provided between the push plate 22 and the limiting plate 23. The barrier 2 is disposed in the lower mold 9, and the lower mold 9 has an ejector pin hole 91 located below the barrier 2.

[0032] Working principle: When the holding pressure in injection cavity 1 ends, the material is still in a plastic state. The ejector roller of the injection molding machine extends into the lower mold 9 through the ejector roller hole 91. The ejector roller pushes the push plate 22, causing the ejector pin 21 to move to the connection between the molding cavity 11 and the runner 12, thereby cutting off the gate 4. Then, in the subsequent cooling process, the product in the molding cavity 11 and the remaining material in the runner 12 will naturally separate, eliminating the need for a cutting process. At the same time, the limiting plate 23 is used to limit the advancement stroke of the push plate 22 to prevent the ejector pin 21 from moving beyond its stroke.

[0033] Example 2 An injection mold internal cutting structure, please refer to Figure 1 , Figure 2 , Figure 5 and Figure 6As shown, the upper mold 8 has a guide post 5 that is inclined away from the molding cavity 11, and the lower mold 9 has a slider 6 that is slidably connected. The slider 6 has a mold core 61 that extends into the molding cavity 11 to assist in product molding. The slider 6 is provided with a guide hole 62 that is adapted to the guide post 5.

[0034] Working principle: During mold closing, the guide pins 5 on the upper mold 8 are inserted into the guide holes 62. As the guide pins 5 continue to penetrate deeper into the guide holes 62, the slider 6 moves towards the molding cavity 11, allowing the mold core 61 to enter the molding cavity 11. During demolding, the upper mold 8 gradually moves away from the lower mold 9, and the guide pins 5 gradually withdraw from the guide holes 62, causing the slider 6 to gradually move away from the molding cavity 11, thus allowing the mold core 61 to withdraw from the molding cavity 11, achieving demolding of the mold core 61 from the product.

[0035] The above description is merely an embodiment of this utility model and does not limit the patent scope of this utility model. Any equivalent modifications made based on the content of this utility model specification and drawings, or direct or indirect applications in related technical fields, are similarly included within the patent protection scope of this utility model.

Claims

1. An injection mold internal structure, comprising an injection cavity (1) formed by the closing of an upper mold (8) and a lower mold (9), wherein the injection cavity (1) includes a connected molding cavity (11) and a runner (12), characterized in that: It also includes a barrier (2) having an ejector pin (21) that moves toward the connection between the molding cavity (11) and the flow channel (12).

2. The injection mold internal slit structure according to claim 1, characterized in that: The barrier (2) also includes a push plate (22) and a limiting plate (23) spaced apart along the moving direction of the ejector pin (21); the ejector pin (21) is connected to the push plate (22).

3. The injection mold internal slit structure according to claim 2, characterized in that: The distance between the push plate (22) and the limiting plate (23) is 1mm to 2mm.

4. The injection mold internal slit structure according to claim 2, characterized in that: An elastic element (3) is provided between the push plate (22) and the limiting plate (23).

5. The injection mold internal slit structure according to claim 1, characterized in that: The ejector pin (21) includes a reinforcing part (211) and a blocking part (212), wherein the cross-sectional area of ​​the reinforcing part (211) is greater than the cross-sectional area of ​​the blocking part (212).

6. The injection mold internal slit structure according to claim 5, characterized in that: The length of the blocking part (212) is 80mm to 100mm.

7. The injection mold in-line structure according to claim 5, characterized in that: The reinforcing part (211) is cylindrical or rectangular, and the blocking part (212) is rectangular.

8. The injection mold internal slit structure according to claim 1, characterized in that: The tip of the pin (21) is needle-shaped.

9. The injection mold internal slit structure according to claim 1, characterized in that: A gate (4) is provided at the connection between the molding cavity (11) and the flow channel (12), and the flow area of ​​the gate (4) gradually decreases toward the molding cavity (11).

10. The injection mold internal slit structure according to claim 1, characterized in that: The barrier (2) is disposed in the lower mold (9), and the lower mold (9) is provided with a top roller hole (91) located below the barrier (2).

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