Ejection structure for demolding of injection mold

Abstract

The utility model discloses an ejection structure for demolding an injection mold. The ejection structure comprises mold frame plates and a positioning frame, wherein the mold frame plates are respectively arranged on two sides and are butted with a rack of an injection molding machine, and the positioning frame is fixedly arranged between the mold frame plates. The positioning frame and one set of formwork plates are fixedly installed in a penetrating mode through four sets of thrust oil cylinders, and the positioning frame and the other set of formwork plates are fixedly installed through four sets of fixing rods. And one side of the positioning frame is connected and provided with a movable mold frame through the thrust oil cylinder, and a fixed mold block is fixedly installed on the mold frame plate on one side of the movable mold frame. And a movable die set is mounted between the movable die frame and the fixed die block. And a plastic part is formed between the movable module and the fixed module through injection molding. According to the utility model, the demoulding completeness of the injection molding buckle is ensured, the situation that the buckle is deformed or broken due to external extrusion once a plastic part containing other buckles is demoulded is avoided, and the demoulding completeness of the plastic part is ensured.

Description

Technical Field

[0001] This utility model belongs to the field of injection molding machine technology, specifically relating to an ejection structure for demolding injection molds. Background Technology

[0002] Injection molding machines, also known as injection molding machines or injection molding machines, are the main molding equipment used to create various shapes of plastic products from thermoplastic or thermosetting plastics using plastic molds. They are classified as vertical, horizontal, and all-electric. Injection molding machines heat the plastic, apply high pressure to the molten plastic, and inject it to fill the mold cavity. Demolding is the final step in the injection molding cycle. When designing the mold, a suitable demolding method must be selected based on the product's structural characteristics to ensure product quality.

[0003] Domestic utility model patent application number 202022538072.5 discloses a demolding mechanism for injection molds, specifically relating to the field of injection molds. It includes a fixed injection mold, a moving injection mold, a guide rod, and a moving valve assembly. The fixed injection mold has an injection cavity inside. An ejector platen is fixedly installed at the bottom end of the guide rod, and a telescopic connecting rod is fixedly installed on the top surface of the ejector platen. The other end of the telescopic connecting rod is embedded in the bottom surface of the fixed injection mold. A pumping ejection mechanism is fixedly installed on the top surface of the ejector platen. A valve receiving cavity is opened on the inner side of the injection cavity, and a negative pressure elimination mechanism is movably installed inside the valve receiving cavity. This utility model, through a novel ejector structure, allows the air inlet head of the pumping ejection mechanism to eject the injection molded part through its upward movement while pumping airflow. The pumping of airflow accelerates the separation of the injection molded part from the injection cavity, making demolding smoother. Simultaneously, the multi-head structure avoids the damage to the injection molded part caused by traditional ejector pin demolding. The aforementioned utility model uses pneumatic pressurization to eject the plastic part, requiring precise control of the molding time. Otherwise, gas may enter the unformed plastic part, forming air bubbles and affecting the molding process. Another demolding method, ejector pin demolding, is not suitable for demolding plastic parts with irregular shapes. Although the plastic part has cooled and solidified, its internal irregular structure may cause uneven stress during demolding, leading to defects such as deformation of the irregular structure during ejection. Utility Model Content

[0004] To address the aforementioned technical problems, this utility model provides an ejection structure for demolding injection molds, comprising mold base plates respectively installed on both sides and connected to the injection molding machine frame, and a positioning frame fixedly installed between the mold base plates. The positioning frame is fixedly installed to one set of mold base plates via four sets of propulsion cylinders, and the positioning frame is fixedly installed to another set of mold base plates via four sets of fixing rods. A movable mold base is connected to one side of the positioning frame via the propulsion cylinders, and a fixed module is fixedly installed on the mold base plate on one side of the movable mold base. A movable mold assembly is installed between the movable mold base and the fixed module. A plastic part is injection molded between the movable mold assembly and the fixed module.

[0005] The moving mold frame is pushed by the hydraulic cylinder, causing the moving mold assembly to move into the fixed mold assembly and injection mold the plastic part.

[0006] As a further preferred technical solution of this utility model, a positioning block is fixedly installed on one side of the positioning frame. The propulsion cylinder has a propulsion rod installed through the positioning frame, and the moving mold frame is fixedly installed to the end of the propulsion rod.

[0007] The hydraulic cylinder pushes the push rod to move, which in turn pushes the moving mold frame to move, thus achieving the mold closing and demolding process in injection molding.

[0008] As a further preferred technical solution of this utility model, an opening is provided in the middle of the moving mold frame. A movable template is slidably mounted on one side of the moving mold frame, and the movable template is slidably mounted to the moving mold frame via two sets of guide blocks. A guide groove is provided on the moving mold frame to cooperate with the sliding of the guide blocks. A top block is provided between the guide blocks at the opening position and fixedly mounted on the movable template. An auxiliary plate is connected and mounted on one side of the movable template via four sets of auxiliary springs, and an ejector pin guide rod is provided inside the auxiliary spring and fixedly mounted on the movable template. A through hole is provided on the auxiliary plate to cooperate with the ejector pin guide rod, and the ejector pin guide rod extends and is mounted to one side of the auxiliary plate.

[0009] When the push rod moves the moving mold frame as a whole, the auxiliary plate pushes the moving module as a whole to move into the fixed module. During demolding, the moving mold frame moves the movable template, causing the auxiliary plate to first move the moving module backward.

[0010] As a further preferred technical solution of this utility model, the moving module includes an inner module fixedly installed on one side of the auxiliary plate, an outer module slidably installed with the inner module, and a push plate installed on one side of the outer module. The outer module and the push plate are connected and installed by four sets of connecting springs. Both the outer module and the push plate are provided with guide holes for sliding with the fixed rod.

[0011] During demolding, the moving mold frame drives the movable template to move, causing the auxiliary plate to first move the inner module. After moving to the designated location, the inner module then drives the outer module to move backward. Since the outer module and the push plate are connected by a connecting spring, the outer module and the push plate move as a whole, achieving the demolding effect.

[0012] As a further preferred technical solution of this utility model, the plastic part is provided with an injection-molded buckle. Slanted locking blocks are fixedly installed at the top and bottom of the inner module. A mounting bracket is snapped onto one side of the outer module, and a connecting block is fixedly installed on the mounting bracket inside the outer module.

[0013] During the demolding process, due to the injection molding clips inside the plastic part, it is necessary to demold the inside and outside separately to ensure the integrity of the injection molding clips. When the inner module is demolded, when the inner module comes out of the injection molding clip position, the inclined block engages and limits the engagement with the mating block on the outer module, driving the outer module to demold together, thereby ensuring the demolding effect of the plastic part.

[0014] As a further preferred technical solution of this utility model, mounting plates are fixedly installed on both the top and bottom of the fixed module, and the mounting plates are connected to the mold frame plate by mounting clips. The fixed module has an injection molding groove inside, and a main flow channel is opened at the center of the fixed module.

[0015] The injection mechanism of the injection molding machine injects material into the injection tank through the main runner, and the material is molded and cooled inside the injection tank before being demolded.

[0016] Beneficial effects

[0017] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0018] 1. During the demolding process, due to the injection-molded clips inside the plastic part, demolding needs to be performed twice, once internally and once externally, to ensure the integrity of the injection-molded clips. When the inner module is demolded, a slanted locking block engages with the mating block on the outer module at the position of the injection-molded clip, thus pulling the outer module out of the mold together and ensuring the demolding effect of the plastic part. This two-stage demolding ensures the integrity of the injection-molded clips, preventing deformation or breakage of the clips due to external pressure when demolding plastic parts containing other clips, thereby guaranteeing the integrity of the plastic part demolding.

[0019] 2. When the auxiliary plate moves the entire moving module backward until the top block collides with the positioning block, the guide block slides out of the guide groove as the auxiliary plate moves backward. This causes the movable template to move the ejector pin guide rod inside the auxiliary spring according to the positioning of the top block. The ejector pin guide rod pushes the push plate out, thereby pushing the plastic part and achieving the ejection effect during the demolding process. This ensures a smooth demolding process for the plastic part. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of this utility model;

[0021] Figure 2 This is a cross-sectional structural diagram of the present invention;

[0022] Figure 3 for Figure 2 Enlarged structural diagram at point A;

[0023] Figure 4 This is a cross-sectional structural diagram of the module location of this utility model;

[0024] Figure 5 for Figure 4 Enlarged structural diagram at point B;

[0025] Figure 6 This is a cross-sectional structural diagram of the internal module snap-fit ​​of this utility model.

[0026] In the diagram: 1. Mold frame plate; 11. Push cylinder; 12. Push rod; 13. Fixing rod; 2. Positioning frame; 21. Positioning block; 3. Moving mold frame; 31. Movable template; 32. Guide groove; 33. Guide block; 34. Top block; 35. Through port; 36. Auxiliary spring; 37. Auxiliary plate; 38. Ejector pin guide rod; 4. Moving module; 41. Inner module; 411. Angled block; 42. Outer module; 421. Mounting frame; 422. Connecting block; 43. Push plate; 44. Connecting spring; 45. Guide hole; 5. Fixed module; 51. Injection groove; 52. Mounting plate; 53. Mounting buckle; 54. Main runner; 6. Plastic part; 61. Injection buckle. Detailed Implementation

[0027] This specific embodiment is an ejection structure for demolding injection molds.

[0028] The aforementioned utility model uses pneumatic pressurization to eject the plastic part, requiring precise control of the molding time. Otherwise, gas may enter the unformed plastic part, forming air bubbles and affecting the molding process. Another demolding method, ejector pin demolding, is not suitable for demolding plastic parts with irregular shapes. Although the plastic part has cooled and solidified, its internal irregular structure may cause uneven stress during demolding, leading to defects such as deformation of the irregular structure during ejection.

[0029] Its structural diagram is as follows Figures 1-6 As shown. An ejection structure for demolding an injection mold includes mold base plates 1, which are respectively installed on both sides and connected to the injection molding machine frame, and positioning frames 2, which are fixedly installed between the mold base plates 1. The positioning frames 2 are fixedly installed to one set of mold base plates 1 through four sets of push cylinders 11, and the positioning frames 2 are fixedly installed to another set of mold base plates 1 through four sets of fixing rods 13. A moving mold base 3 is connected to one side of the positioning frame 2 through the push cylinder 11, and a fixed module 5 is fixedly installed on the mold base plate 1 on one side of the moving mold base 3. A positioning block 21 is fixedly installed on one side of the positioning frame 2. A push rod 12 is installed through the push cylinder 11 through the positioning frame 2, and the moving mold base 3 is fixedly installed to the end of the push rod 12. The push cylinder 11 pushes the push rod 12 to move, which in turn pushes the moving mold base 3 to move, achieving the process of mold closing and demolding during injection molding. A moving mold assembly 4 is installed between the moving mold base 3 and the fixed module 5. A plastic part 6 is injection molded between the moving mold assembly 4 and the fixed module 5.

[0030] A through-hole 35 is provided in the middle of the moving mold frame 3. A movable template 31 is slidably mounted on one side of the moving mold frame 3, and the movable template 31 is slidably mounted to the moving mold frame 3 via two sets of guide blocks 33. A guide groove 32 is provided on the moving mold frame 3 to slide with the guide blocks 33. A top block 34 is fixedly mounted on the movable template 31 at the through-hole 35 between the guide blocks 33. An auxiliary plate 37 is connected and mounted on one side of the movable template 31 via four sets of auxiliary springs 36, and an ejector pin guide rod 38 is fixedly mounted on the movable template 31 inside the auxiliary springs 36. The auxiliary plate 37 has a through hole to cooperate with the ejector pin guide rod 38, and the ejector pin guide rod 38 extends to one side of the auxiliary plate 37. When the push rod 12 pushes the moving mold frame 3 to move as a whole, the auxiliary plate 37 pushes the moving mold assembly 4 to move as a whole into the fixed mold assembly 5. During demolding, the moving mold frame 3 drives the movable template 31 to move, so that the auxiliary plate 37 first drives the moving mold assembly 4 to move backward. The moving module 4 includes an inner module 41 fixedly mounted on one side of the auxiliary plate 37, an outer module 42 slidably mounted to the inner module 41, and a push plate 43 mounted on one side of the outer module 42. The outer module 42 and the push plate 43 are connected by four sets of connecting springs 44. Both the outer module 42 and the push plate 43 have guide holes 45 that slide with the fixing rod 13. During demolding, the moving mold frame 3 drives the movable template 31 to move, causing the auxiliary plate 37 to first move the inner module 41. After moving to the designated location, the inner module 41 then drives the outer module 42 to move backward. Since the outer module 42 and the push plate 43 are connected by connecting springs 44, the outer module 42 and the push plate 43 move as a whole, achieving the demolding effect. When the auxiliary plate 37 moves the entire movable module 4 backward until the top block 34 collides with the positioning block 21, the guide block 33 slides out of the guide groove 32 as the auxiliary plate 37 moves backward. This causes the movable template 31 to move the ejector pin guide rod 38 inside the auxiliary spring 36 according to the positioning of the top block 34. The ejector pin guide rod 38 then pushes the push plate 43 out, thereby pushing the plastic part 6 and achieving the ejection effect during the demolding process. This ensures the smooth demolding of the plastic part 6.

[0031] The plastic part 6 has an injection-molded clip 61 inside. Angled clips 411 are fixedly installed at the top and bottom of the inner module 41. A mounting bracket 421 is snapped onto one side of the outer module 42, and a mating block 422 is fixedly installed on the mounting bracket 421 inside the outer module 42. During demolding, due to the injection-molded clip 61 inside the plastic part 6, demolding needs to be performed twice, once inside and once outside, to ensure the integrity of the injection-molded clip 61. When the inner module 41 is demolded, when it exits the position of the injection-molded clip 61, the angled clip 411 engages and limits the engagement with the mating block 422 on the outer module 42, causing the outer module 42 to demold together, thus ensuring the demolding effect of the plastic part 6. The two-stage demolding ensures the integrity of the injection-molded clip 61, preventing deformation or breakage of the clips due to external pressure when demolding plastic parts 6 containing other clips, thus ensuring the integrity of the demolding of the plastic part 6. Mounting plates 52 are fixedly installed on both the top and bottom of the fixed module 5, and the mounting plates 52 are snapped into the mold base plate 1 by mounting clips 53. The fixed module 5 has an injection tank 51 inside, and a main runner 54 is opened at the center of the fixed module 5. The injection mechanism of the injection molding machine injects material into the injection tank 51 through the main runner 54, allowing the material to be molded and cooled inside the injection tank 51 before demolding.

[0032] First, when the push rod 12 moves the moving mold frame 3 as a whole, the auxiliary plate 37 pushes the moving mold assembly 4 as a whole to move into the fixed module 5. The injection mechanism of the injection molding machine injects material into the injection tank 51 through the main runner 54. After the material is injection molded and cooled inside the injection tank 51, the moving mold frame 3 drives the movable template 31 to move, causing the auxiliary plate 37 to first move the moving mold assembly 4 backward for demolding. During demolding, the moving mold frame 3 drives the movable template 31 to move, causing the auxiliary plate 37 to first move the inner module 41. After moving to the designated location, the inner module 41 then drives the outer module 42 to move backward. Since the outer module 42 and the push plate 43 are connected by a connecting spring 44, the outer module 42 and the push plate 43 move as a whole, achieving the demolding effect. When the auxiliary plate 37 moves the entire movable module 4 backward until the top block 34 collides with the positioning block 21, the guide block 33 slides out of the guide groove 32 as the auxiliary plate 37 moves backward. This causes the movable template 31 to move the ejector pin guide rod 38 inside the auxiliary spring 36 according to the positioning of the top block 34. The ejector pin guide rod 38 then pushes the push plate 43 out, thereby pushing the plastic part 6 and achieving the ejection effect during the demolding process. This ensures the smooth demolding of the plastic part 6.

[0033] All technical features in this embodiment can be freely combined according to actual needs.

[0034] The above embodiments are preferred implementations of this utility model. In addition, this utility model can also be implemented in other ways. Any obvious substitutions without departing from the concept of this technical solution are within the protection scope of this utility model.

Claims

1. An ejection structure for demolding of an injection mold, characterized in that, The utility model provides a mould frame plate (1) and the positioning frame (2) are installed to the injection molding machine frame, and the positioning frame (2) is fixedly installed between the mould frame plate (1), and the positioning frame (2) is fixedly installed between the mould frame plate (1) through four groups of advance oil cylinder (11), and the positioning frame (2) and another group of mould frame plate (1) between through four groups of fixed rod (13) fixedly installed, one side of positioning frame (2) is connected and is installed with movable mould frame (3) through advance oil cylinder (11), and the mould frame plate (1) on one side of movable mould frame (3) is fixedly installed with fixed mould block (5), and movable mould frame (3) and fixed mould block (5) between installation has movable mould group (4), and movable mould group (4) and fixed mould block (5) between injection plastic part (6).

2. A ejection structure for demolding of an injection mold according to claim 1, characterized in that: One side of positioning frame (2) is fixedly installed with locating block (21), advance oil cylinder (11) is installed with advance rod (12) through positioning frame (2), and movable mould frame (3) and advance rod (12) end fixedly installed.

3. A ejection structure for demolding of an injection mold according to claim 2, characterized in that: The middle position of movable mould frame (3) is provided with a through port (35), and a movable mold plate (31) is slidably installed on one side of the movable mold frame (3). The movable mold plate (31) and the movable mold frame (3) are slidably installed through two groups of guide blocks (33). The movable mold frame (3) is provided with a guide groove (32) for sliding the guide blocks (33). The guide blocks (33) are provided with a top block (34) fixedly installed on the movable mold plate (31) at the position of the through port (35). The movable mold plate (31) is connected and installed with an auxiliary plate (37) on one side through four groups of auxiliary springs (36). The auxiliary springs (36) are provided with a thimble guide rod (38) fixedly installed on the movable mold plate (31) inside. The thimble guide rod (38) extends and is installed to one side of the auxiliary plate (37).

4. The ejection structure for injection mold demolding according to claim 3, characterized in that: The movable mold group (4) includes an inner mold block (41) fixedly installed on one side of the auxiliary plate (37), an outer mold block (42) slidably installed with the inner mold block (41), and a push plate (43) installed on one side of the outer mold block (42). The outer mold block (42) and the push plate (43) are connected and installed through four groups of connecting springs (44). The outer mold block (42) and the push plate (43) are both provided with a guide hole (45) for sliding the fixed rod (13).

5. A ejection structure for demolding of an injection mold according to claim 4, characterized in that: The plastic part (6) is provided with an injection buckle (61) inside. The inner mold block (41) is fixedly installed with inclined clamping blocks (411) on the top and bottom. The outer mold block (42) is connected and installed with a mounting frame (421) on one side. The mounting frame (421) is fixedly installed with a butt joint block (422) inside the outer mold block (42).

6. A ejection structure for demolding of an injection mold according to claim 5, characterized in that: The bottom of the fixed mold module (5) is fixedly installed with an installation plate (52), and the installation plate (52) and the mold frame plate (1) are connected through a mounting buckle (53). The fixed mold module (5) is internally provided with an injection molding groove (51), and a main runner (54) is arranged at the center position of the fixed mold module (5).

Images