Plastic mold with exhaust structure

Abstract

The utility model relates to the technical field of plastic mould discloses a plastic mould with exhaust structure, including fixed mould and movable mould, the fixed mould one side is provided with the sprue, the fixed mould and movable mould four corners all are connected with the connecting frame that is provided, the connecting frame one side all is connected with the connecting rod base that is provided, the movable mould inside is provided with compression cavity, the compression cavity inner wall bottom end is connected with the sealing assembly that is provided, the movable mould and the fixed mould one side that is close to each other all are provided with the forming cavity. The utility model through the cooperation of air cylinder and suction plate can extract the air in the forming cavity, makes it form negative pressure, the air -tight component can avoid the reflux of the extracted gas, played the effect of limiting the one -way flow of gas, through the sealing ring and the guaranteeing of the close -fit groove between fixed mould and movable mould connection tightness, guarantee the air -tightness, through sealing assembly further promotion negative pressure keeps state's stability, can through the barometer detection internal air pressure state, guarantee use safety.

Description

Technical Field

[0001] This utility model relates to the field of plastic mold technology, specifically a plastic mold with a venting structure. Background Technology

[0002] During plastic mold reprocessing, air inside the mold cavity is pushed out at high speed by the molten plastic. If there is no outlet, the air will be compressed and form a high-pressure zone, preventing the molten plastic from filling the entire cavity. This results in insufficient material in the product, rendering it scrap. The highly compressed gas can instantly generate extremely high temperatures (similar to a diesel engine), enough to cause localized overheating, decomposition, and carbonization of the plastic it comes into contact with. This not only affects the appearance but also reduces the mechanical strength of that area. Gas trapped inside the plastic, or moisture and volatile gases within the plastic, cannot escape and will form bubbles. These bubbles may be inside the product (vacuum bubbles) or on the surface, affecting the product's strength, transparency, and appearance quality.

[0003] Traditional venting methods mainly involve creating venting grooves on the parting surface and utilizing the mating gaps of ejector pins, inserts, and other components for venting. Traditional venting is passive, relying on the gas to find its own way out. Venting grooves are usually made directly on the mold steel through machining (such as milling machines or EDM), which is prone to clogging and requires frequent cleaning. Utility Model Content

[0004] The purpose of this invention is to provide a plastic mold with a venting structure to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, this utility model provides the following technical solution: It includes a fixed mold and a moving mold. A gate is provided on one side of the fixed mold. Connecting frames are provided at the four corners of both the fixed mold and the moving mold. A connecting rod base is provided on one side of each connecting frame. A compression cavity is provided inside the moving mold. A sealing component is provided at the bottom of the inner wall of the compression cavity. A molding cavity is provided on the side of the moving mold and the fixed mold that are close to each other. Multiple airtight components are provided inside the molding cavity on the side of the moving mold. A cylinder is connected to one side of the moving mold. The output end of the cylinder extends into the compression cavity and is connected to an air extraction plate. Two guide pipes are connected to the back side of the air extraction plate.

[0006] Preferably, the sealing assembly includes multiple sets of limit bolts fixedly disposed at the bottom of the inner wall of the compression chamber and a pneumatic motor disposed on one side of the moving mold. The output end of the pneumatic motor is connected to a drive gear, and a sealing plate is connected between the limit bolts. One side of the sealing plate meshes with the drive gear.

[0007] Preferably, the sealing plate has an arc-shaped guide hole on its surface corresponding to the limiting bolt, and a sealing gasket is connected to one side of the sealing plate. The sealing gasket is attached to one side of the inner wall of the compression chamber, and the bottom surface of the sealing plate has an flared opening corresponding to each airtight component.

[0008] Preferably, the airtight component includes an air extraction hole located on one side of the forming cavity inside the moving mold. A fixing frame is connected to the inner side of each air extraction hole. A return spring is connected to the bottom surface of each fixing frame. An airtight plug is connected to the other end of each return spring. A guide rod is connected to the top of the airtight plug, and the guide rod is slidably connected to the fixing frame. The airtight plug is fitted into the bottom end of the air extraction hole.

[0009] Preferably, a positioning rod is connected to one side of the moving mold, and a positioning hole is provided on the side of the fixed mold corresponding to the positioning rod.

[0010] Preferably, a sealing ring is connected to the side of the moving mold near the fixed mold, and a fitting groove is formed on the side of the fixed mold near the moving mold corresponding to the sealing ring.

[0011] Preferably, the top ends of both guide tubes penetrate the moving mold and are respectively connected to a pressure gauge and a pressure relief valve.

[0012] In summary, this application includes the following beneficial technical effects: The combination of cylinder and suction plate can extract air from the molding cavity, creating negative pressure and allowing for faster injection speeds. The airtight components prevent the extracted gas from flowing back, effectively restricting unidirectional gas flow. The combination of sealing ring and fitting groove ensures a tight connection between the fixed mold and moving mold after mold closing, guaranteeing airtightness. The sealing components further enhance the stability of the negative pressure state within the molding cavity. The internal air pressure can be monitored using a pressure gauge, ensuring safe operation. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the overall structure of a plastic mold with a venting structure according to the present invention; Figure 2 This is a schematic diagram of a plastic mold separation structure with an exhaust structure according to the present invention; Figure 3 This is a side sectional view of a plastic mold with a venting structure according to the present invention; Figure 4 This is a partial structural diagram of a plastic mold with an venting structure according to the present invention.

[0014] In the diagram: 1. Fixed mold; 2. Moving mold; 3. Gate; 4. Connecting frame; 5. Connecting rod base; 6. Compression chamber; 7. Limiting bolt; 8. Sealing plate; 9. Arc-shaped guide hole; 10. Evacuation hole; 11. Fixed frame; 12. Airtight plug; 13. Return spring; 14. Sealing gasket; 15. Pneumatic motor; 16. Drive gear; 17. Cylinder; 18. Evacuation plate; 19. Guide air pipe; 20. Pressure gauge; 21. Pressure relief valve; 22. Sealing ring; 23. Fitting groove; 24. Positioning rod; 25. Positioning hole; 111. Molding cavity. Detailed Implementation

[0015] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0016] Please see Figure 1-4 This utility model provides a technical solution: it includes a fixed mold 1 and a moving mold 2. A gate 3 is provided on one side of the fixed mold 1. Connecting frames 4 are connected to the four corners of both the fixed mold 1 and the moving mold 2. A connecting rod base 5 is connected to one side of each connecting frame 4. A compression cavity 6 is provided inside the moving mold 2. A sealing component is connected to the bottom of the inner wall of the compression cavity 6. A molding cavity 111 is provided on the side of the moving mold 2 and the fixed mold 1 that are close to each other. Multiple airtight components are provided inside the molding cavity 111 located on the side of the moving mold 2. A cylinder 1 is connected to one side of the moving mold 2. 7. The output end of cylinder 17 extends into the compression chamber 6 and is connected to an air extraction plate 18. Two guide air pipes 19 are connected to the back side of the air extraction plate 18. The top ends of the two guide air pipes 19 penetrate the moving mold 2 and are respectively connected to a pressure gauge 20 and a pressure relief valve 21. The guide air pipes 19 can guide the air extraction plate 18. The pressure gauge 20 can also detect the air pressure inside the compression chamber 6 when the air in the forming chamber 111 is extracted. After the work is completed, the pressure relief valve 21 is opened to release the pressure through the guide air pipes 19.

[0017] Reference Figure 4 As shown, the sealing assembly includes multiple sets of limit bolts 7 fixedly installed at the bottom of the inner wall of the compression chamber 6 and a pneumatic motor 15 installed on one side of the moving mold 2. The output end of the pneumatic motor 15 is connected to a drive gear 16. A sealing plate 8 is connected between the limit bolts 7. One side of the sealing plate 8 has teeth and meshes with the drive gear 16. After the cylinder 17 drives the suction plate 18 to perform suction, the pneumatic motor 15 is started to drive the drive gear 16 to rotate, which drives the sealing plate 8 to rotate, so that the flared opening on the sealing plate 8 is misaligned with the suction hole 10. The suction hole 10 is sealed by the sealing gasket 14, thereby ensuring the negative pressure state in the molding cavity 111 formed by the fixed mold 1 and the moving mold 2 after merging. The sealing plate 8 has an arc-shaped guide hole 9 on its surface corresponding to the limiting bolt 7, and a sealing gasket 14 is connected to one side. The sealing gasket 14 is attached to one side of the inner wall of the compression chamber 6. The bottom surface of the sealing plate 8 has an flared opening corresponding to each airtight component. The drive gear 16 drives the sealing plate 8 to rotate in the compression chamber 6. The rotation range of the sealing plate 8 is limited by the connection between the limiting bolt 7 and the arc-shaped guide hole 9. At the same time, the limiting bolt 7 can limit the position of the sealing plate 8, so that the sealing gasket 14 is attached to the inner surface of the compression chamber 6.

[0018] Reference Figure 4 As shown, the airtight assembly includes an air extraction hole 10 located on one side of the forming cavity 111 inside the moving mold 2. A fixing frame 11 is connected to the inner side of each air extraction hole 10, and a return spring 13 is connected to the bottom surface of each fixing frame 11. An airtight plug 12 is connected to the other end of each return spring 13. A guide rod is connected to the top of the airtight plug 12, and the guide rod is slidably connected to the fixing frame 11. The airtight plug 12 is fitted into the bottom end of the air extraction hole 10. When the cylinder 17 contracts, causing the extraction plate 18 to move, air can be released through the airtight... The component extracts air from the molding cavity 111. During extraction, the air pushes open the airtight plug 12 and enters the compression cavity 6 through the air extraction hole 10. After the air enters the compression cavity 6, the cylinder 17 extends and pushes the air extraction plate 18 to move in the opposite direction, thereby forming high pressure in the compression cavity 6. Due to the shape of the airtight plug 12 and the air extraction hole 10, the high pressure will squeeze the airtight plug 12 to block the air extraction hole 10, ensuring the sealing integrity of the molding cavity 111, and at the same time preventing the raw material from clogging the air extraction hole 10 during injection molding.

[0019] Reference Figure 2 As shown, a positioning rod 24 is connected to one side of the moving mold 2, and a positioning hole 25 is opened on one side of the fixed mold 1 corresponding to the positioning rod 24. When the injection molding equipment pushes the moving mold 2 to move towards the fixed mold 1, the positioning rod 24 will be inserted into the positioning hole 25, thereby ensuring accurate positioning when the fixed mold 1 and the moving mold 2 are combined.

[0020] Reference Figure 3 As shown, a sealing ring 22 is connected to the side of the moving mold 2 that is close to the fixed mold 1. A fitting groove 23 is opened on the side of the fixed mold 1 that is close to the moving mold 2, corresponding to the sealing ring 22. When the fixed mold 1 and the moving mold 2 are combined, the sealing ring 22 will be inserted into the fitting groove 23, thereby improving the sealing performance of the molding cavity 111 after the fixed mold 1 and the moving mold 2 are combined, which facilitates the sealing performance of the subsequent air extraction work.

[0021] The implementation principle of this application is as follows: When this utility model is in use, the fixed mold 1 and the moving mold 2 are installed on the injection molding device through the connecting rod base 5. When the mold is closed, the hydraulic cylinder on the injection molding device pushes the moving mold 2 to move towards the fixed mold 1. At this time, the positioning rod 24 will be inserted into the positioning hole 25, and the sealing ring 22 will be locked into the fitting groove 23 to ensure accurate mold closing and sealing. After the mold is closed, the cylinder 17 is activated, causing it to contract and move the suction plate 18 into the compression chamber 6. This allows air in the molding chamber 111 to be drawn into the compression chamber 6 through the suction port 10. After suction, the cylinder 17 extends, pushing the suction plate 18 to compress the air in the compression chamber 6. The compressed air pushes the airtight plug 12 to block the suction port 10, thus maintaining the negative pressure in the molding chamber 111 while preventing the injection molding material from blocking the exhaust channel. Then, the pneumatic motor 15 is activated to drive the gear 16, causing the sealing plate 8 to rotate, so that the sealing gasket 14 on it completely covers the inlet of each suction port 10, achieving secondary sealing. After injection molding, the cylinder 17 is first contracted to initially reduce pressure, and then the pressure relief valve 21 is opened for complete pressure relief.

[0022] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0023] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A plastic mold with a venting structure, comprising a fixed mold (1) and a moving mold (2), characterized in that: A gate (3) is provided on one side of the fixed mold (1). A connecting frame (4) is provided at each of the four corners of the fixed mold (1) and the moving mold (2). A connecting rod base (5) is provided on one side of each connecting frame (4). A compression cavity (6) is provided inside the moving mold (2). A sealing component is connected to the bottom of the inner wall of the compression cavity (6). A molding cavity (111) is provided on the side of the moving mold (2) and the fixed mold (1) that are close to each other. Multiple airtight components are provided inside the molding cavity (111) on one side of the moving mold (2). A cylinder (17) is connected to one side of the moving mold (2). The output end of the cylinder (17) extends into the compression cavity (6) and is connected to an air extraction plate (18). Two guide air pipes (19) are connected to the back side of the air extraction plate (18).

2. A plastic mold with a venting structure according to claim 1, characterized in that: The sealing assembly includes multiple sets of limit bolts (7) fixedly disposed at the bottom of the inner wall of the compression chamber (6) and a pneumatic motor (15) disposed on one side of the moving mold (2). The output end of the pneumatic motor (15) is connected to a drive gear (16). A sealing plate (8) is connected between the limit bolts (7). One side of the sealing plate (8) meshes with the drive gear (16).

3. The plastic mold with venting structure according to claim 2, wherein: The sealing plate (8) has an arc-shaped guide hole (9) on its surface corresponding to the limiting bolt (7), and a sealing gasket (14) is connected to one side. The sealing gasket (14) is attached to one side of the inner wall of the compression chamber (6), and the bottom surface of the sealing plate (8) has an flared opening corresponding to each airtight component.

4. A plastic mold with a venting structure according to claim 3, characterized in that: The airtight component includes an air extraction hole (10) located on one side of the forming cavity (111) inside the moving mold (2). A fixing frame (11) is connected to the inner side of each air extraction hole (10). A return spring (13) is connected to the bottom surface of each fixing frame (11). An airtight plug (12) is connected to the other end of the return spring (13). A guide rod is connected to the top of the airtight plug (12), and the guide rod is slidably connected to the fixing frame (11). The airtight plug (12) is fitted into the bottom end of the air extraction hole (10).

5. The plastic mold with venting structure according to claim 1, wherein: A positioning rod (24) is connected to one side of the moving mold (2), and a positioning hole (25) is opened on one side of the fixed mold (1) corresponding to the positioning rod (24).

6. A plastic mold with a venting structure according to claim 1, characterized in that: A sealing ring (22) is connected to the side of the moving mold (2) close to the fixed mold (1), and a fitting groove (23) is opened on the side of the fixed mold (1) close to the moving mold (2) corresponding to the sealing ring (22).

7. A plastic mold with a venting structure according to claim 1, characterized in that: The top ends of the two guide air pipes (19) both penetrate the moving mold (2) and are respectively connected to a pressure gauge (20) and a pressure relief valve (21).

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