Exhaust device of injection mold

Abstract

The exhaust device comprises a base and a top plate, a lower mold is fixedly arranged on the upper portion of the base, a forming groove is formed in the upper portion of the lower mold, and hydraulic air cylinders are fixedly connected to the left side and the right side of the bottom of the top plate correspondingly; the telescopic ends of the hydraulic air cylinders are fixedly connected with upper molds and forming blocks, the left side and the right side of the interior of each forming block are each provided with an installation space, and exhaust units are arranged in the installation spaces. Gas in the forming space is exhausted through the exhaust unit, when the gas is pressed and accumulated due to melt filling in the injection molding process, the miniature air cylinder drives the plug block to open the gas inlet pipeline, the gas is exhausted through the exhaust pipeline, and the defects of bubbles, shrinkage cavities, surface weld marks and the like caused by untimely exhaust in the traditional process can be effectively eliminated; and in addition, manual intervention is not needed through automatic exhaust, and the single-time production period is shortened.

Description

Technical Field

[0001] The present invention relates to the technical field of injection molding production, and particularly relates to an exhaust device for an injection mold. Background Art

[0002] Injection molding is a widely recognized manufacturing process that can precisely and efficiently produce a large number of plastic and metal parts. It is the cornerstone of mass-producing identical parts and is widely used in various industries from automotive to consumer electronics. During the injection molding production process, if the gas in the mold cannot be discharged in time, it will cause defects such as bubbles, material shortage, and weld lines in the plastic part, affecting product quality and production efficiency. Traditional exhaust methods mostly use fixed exhaust grooves or holes opened on the mold parting surface, but their exhaust effect depends on manual experience adjustment, and there are problems such as difficulty in accurately controlling the exhaust timing, easy occurrence of molten material leakage or incomplete exhaust. Especially for molds with complex structures, gas is easily trapped in the dead corners of the molding space, resulting in an increase in the scrap rate. In addition, the maintenance cost of traditional exhaust structures is high, and the blockage needs to be cleaned frequently, and it is difficult to adapt to different specifications of injection molding equipment and production requirements, restricting the automation and high-precision development of the injection molding process.

[0003] According to an injection mold disclosed in a Chinese patent (publication number CN221022218U), it includes a first mold, a second mold, a low-temperature storage device, and a high-temperature storage device; the second mold can be horizontally moved and then clamped with the first mold; a temperature control channel is opened on the first mold, and the temperature control channel is arranged in a serpentine shape from top to bottom. There is temperature control liquid in the temperature control channel, and a driving pump is provided on the first mold to pump the temperature control liquid in the temperature control channel. Although when in use, the higher-temperature temperature control liquid in the high-temperature storage device is pumped into the temperature control channel by the driving pump, making the mold heat up more efficiently, and the driving pump can also pump the low-temperature temperature control liquid in the low-temperature storage device into the temperature control channel to cool the mold. However, when the injection mold is in use, the hot-melt plastic flows and squeezes the air in the cavity. If it cannot be effectively discharged, it will cause air entrapment, and the unsmooth discharge of gas will lead to incomplete filling of the mold cavity in the mold, which will affect the injection molding of the product. Therefore, a corresponding exhaust mechanism is needed to discharge the trapped air. Therefore, it is not convenient to discharge the air generated during the injection molding process, and at the same time, the exhaust mechanism will have certain wear and even damage after long-term use, which will affect the exhaust process and make it inconvenient to disassemble and maintain the exhaust mechanism during use. It is necessary to design an exhaust device for an injection mold to solve the above-mentioned problems. Summary of the Invention

[0004] To achieve the above object, the present invention is realized through the following technical solutions: It includes a base and a top plate. A lower mold is fixedly arranged on the upper part of the base. A forming groove is arranged on the upper part of the lower mold. Hydraulic cylinders are fixedly connected to the left and right sides of the bottom of the top plate. The telescopic ends of the hydraulic cylinders are fixedly connected with upper molds. A forming block is fixedly arranged at the bottom of the upper mold. The forming block fits with the forming groove. Installation spaces are arranged on the left and right sides inside the forming block. Exhaust units are arranged inside the installation spaces. Intake pipes are communicated with the bottoms of the installation spaces respectively. The intake pipes penetrate through the left and right sides of the bottom of the forming block respectively. Exhaust pipes are communicated with the upper parts of the installation spaces respectively. The exhaust pipes penetrate through the middle parts of the left and right sides of the forming block respectively.

[0005] Preferably, each of the exhaust units includes a micro cylinder. The telescopic ends of the micro cylinders are fixedly connected with plug blocks. The bottoms of the plug blocks respectively block the upper parts of the corresponding intake pipes.

[0006] By adopting the above technical solution, the micro cylinder realizes the automatic opening and closing of the intake pipe by precisely controlling the movement of the plug block.

[0007] Preferably, sealing rubber plates are arranged on the outer sides of the telescopic ends of the micro cylinders. Springs are arranged on the outer sides of the sealing rubber plates. Connecting sleeves are arranged on the upper parts of the sealing rubber plates. The telescopic ends of the micro cylinders are slidably connected to the inner sides of the corresponding connecting sleeves.

[0008] By adopting the above technical solution, the spring pushes the sealing rubber plate through elastic force, reducing the space volume inside the installation space to prevent gas from damaging the micro cylinder.

[0009] Preferably, sliders are arranged at the upper ends of the plug blocks. Chute grooves are arranged on the upper parts of the installation spaces. The sliders are respectively slidably connected to the inner sides of the corresponding chute grooves. Limit blocks are fixedly connected to the inner ends of the installation spaces.

[0010] By adopting the above technical solution, the sliding fit between the slider and the chute groove provides guidance for the plug block, ensuring that it remains horizontal during movement and avoiding sealing failure caused by inclination.

[0011] Preferably, check valves are installed on the outer sides of the exhaust pipes. Pressure detection devices are arranged on the outer sides of the intake pipes.

[0012] By adopting the above technical solution, the check valve ensures unidirectional gas discharge, preventing external gas or molten material from flowing back during the exhaust process; the pressure detection device monitors the air pressure in the forming space in real time and automatically triggers exhaust when the pressure exceeds the preset threshold.

[0013] Preferably, support columns are fixedly connected to the four corners at the upper end of the base, and the upper ends of the support columns are respectively fixedly connected to the four corners at the bottom of the top plate.

[0014] By adopting the above technical solution, the support columns form a rigid frame structure to evenly bear the vertical pressure of the mold during the injection molding process.

[0015] Preferably, sliding rods are fixedly connected to the four corners in the middle between the base and the top plate, and the middle parts on the left and right sides of the upper mold are respectively slidably connected to the outer sides of the sliding rods.

[0016] By adopting the above technical solution, the sliding rods provide linear guidance for the up and down movement of the upper mold, reducing the shaking and offset during the movement process.

[0017] In summary, the present invention provides an exhaust device for an injection mold, which has the following beneficial effects: 1. Through the pressure detection device and the exhaust unit, the real-time monitoring and automatic response of the air pressure in the forming space are realized. When the gas accumulates under pressure due to the filling of the molten material during the injection molding process and the air pressure exceeds the preset threshold, the pressure detection device triggers the action of the micro cylinder, driving the plug block to move along the chute, opening the intake pipe, and discharging the gas through the exhaust pipe and the one-way valve, which can effectively eliminate defects such as bubbles, shrinkage cavities, and surface weld marks caused by untimely exhaust in the traditional process, reduce the surface roughness of the plastic part, and reduce the internal porosity. In addition, automatic exhaust does not require manual intervention, shortening the single production cycle.

[0018] 2. The base and the top plate form a rigid frame structure through the support columns at the four corners, and cooperate with the linear guidance of the middle sliding rods for the movement of the mold, so as to control the perpendicularity error when the upper mold is closed, avoiding the misalignment or sealing failure of the exhaust channel caused by the offset of the mold. At the same time, the exhaust unit adopts an elastic sealing structure of a spring and a sealing rubber plate. The spring 603 provides an initial pre-tightening force to ensure static sealing, and the sealing rubber plate compensates for mechanical gaps through deformation, and can still maintain airtightness under the high-pressure impact of the injection molding molten material, improving the continuous production life of the mold. In addition, the guidance of the sliding rods reduces the lateral load of the hydraulic cylinder.

[0019] 3. The intake pipe penetrates the bottom of the forming block and is directly connected to the forming groove, while the exhaust pipe is distributed in the middle of the forming block, forming a three-dimensional flow path of bottom intake and middle exhaust. For plastic parts with complex structures such as undercuts and multiple bosses, it can effectively discharge the dead-end gas that is difficult to cover by traditional side-gap exhaust, improving the qualified rate. Description of the Drawings

[0020] Figure 1 is a three-dimensional structural schematic diagram of an exhaust device for an injection mold according to the present invention; Figure 2 is a front view of an exhaust device for an injection mold according to the present invention; Figure 3 Schematic diagram of the internal structure of the forming block of an exhaust device for an injection mold according to the present invention; Figure 4 Enlarged schematic diagram of part A of an exhaust device for an injection mold according to the present invention.

[0021] Explanation of reference numerals: 1, base; 2, lower mold; 201, forming groove; 3, top plate; 4, upper mold; 5, forming block; 501, intake pipe; 502, installation space; 503, exhaust pipe; 6, exhaust unit; 601, micro cylinder; 602, sealing rubber plate; 603, spring; 604, connecting sleeve; 605, plug; 606, slider; 607, chute; 608, limit block; 7, support column; 8, hydraulic cylinder; 9, slide bar; 10, check valve; 11, pressure detection device. Detailed implementation manners

[0022] The following will Figure 1 - be Figure 4 further described in detail in conjunction with the attached

[0023] Embodiment: The present invention provides a technical solution: an exhaust device for an injection mold, including a base 1 and a top plate 3. A lower mold 2 is fixedly arranged on the upper part of the base 1, a forming groove 201 is arranged on the upper part of the lower mold 2, hydraulic cylinders 8 are fixedly connected to both the left and right sides of the bottom of the top plate 3, the telescopic ends of the hydraulic cylinders 8 are fixedly connected with an upper mold 4, a forming block 5 is fixedly arranged at the bottom of the upper mold 4, the forming block 5 fits with the forming groove 201, installation spaces 502 are arranged on both the left and right sides inside the forming block 5, and exhaust units 6 are arranged inside the installation spaces 502. By driving the upper mold 2 and the lower mold 4 to close through the hydraulic cylinders 8, a closed forming space is formed. The exhaust units 6 integrated inside the forming block 5 can directly exhaust the forming area, avoiding defects such as air bubbles and material shortage in the plastic part caused by gas retention, and improving the product yield; Intake pipes 501 are communicated and arranged at the bottoms of the installation spaces 502, the intake pipes 501 are distributed and penetrate through the left and right sides of the bottom of the forming block 5, exhaust pipes 503 are communicated and arranged at the upper parts of the installation spaces 502, the exhaust pipes 503 are distributed and penetrate through the middle parts of the left and right sides of the forming block 5. The intake pipes 601 and the exhaust pipes 603 are arranged in an upper and lower layered layout, shortening the gas flow path, enabling the gas in the forming space to be quickly introduced into the installation space 602 through the intake pipe 601 and then discharged through the exhaust pipe 603, improving the exhaust efficiency and reducing the gas retention time.

[0024] The exhaust units 6 each include a micro cylinder 601. The telescopic ends of the micro cylinders 601 are fixedly connected with plug blocks 605. The bottoms of the plug blocks 605 respectively seal the upper parts of the corresponding intake pipes 501. The micro cylinder 601 realizes the automatic opening and closing of the intake pipe 501 by precisely controlling the movement of the plug block 605. During injection molding, the plug block 605 seals the pipe to prevent the molten material from infiltrating. When the air pressure exceeds the standard, the intake pipe 501 is quickly opened for exhaust, avoiding manual intervention and making the exhaust process dynamically match the injection pressure.

[0025] On the outer sides of the telescopic ends of the micro cylinders 601, sealing rubber plates 602 are provided. On the outer sides of the sealing rubber plates 602, springs 603 are provided. On the upper parts of the sealing rubber plates 602, connecting sleeves 604 are provided. The telescopic ends of the micro cylinders 601 are slidably connected to the inner sides of the corresponding connecting sleeves 604. The spring 603 pushes the sealing rubber plate 602 through the elastic force, reducing the amount of space inside the installation space 502, preventing the gas from damaging the micro cylinder 601. At the same time, the joints of the telescopic ends of the micro cylinder 601 are connected through the connecting sleeve 604 to form a flexible sealing structure, compensating for the mechanical fit clearance, preventing the injection molding molten material from infiltrating through the gap, and the elastic deformation of the sealing rubber plate 602 can buffer the movement impact of the micro cylinder 601 and extend the service life of the components.

[0026] On the upper ends of the plug blocks 605, sliders 606 are provided. On the upper parts of the installation spaces 502, chutes 607 are provided. The sliders 606 are respectively slidably connected to the inner sides of the corresponding chutes 607. At the inner ends of the installation spaces 502, limit blocks 608 are fixedly connected. The sliding fit between the slider 606 and the chute 607 provides guidance for the plug block 605 to ensure that it remains horizontal during movement and avoid tilting resulting in sealing failure. The limit block 608 limits the inner movement stroke of the plug block 605 to prevent component collision damage caused by over-driving. At the same time, the chute 607 ensures that the plug 605 accurately seals the intake pipe 501 when it returns to its original position.

[0027] One-way valves 10 are installed on the outer sides of the exhaust pipes 503. Pressure detection devices 11 are provided on the outer sides of the intake pipes 501. The one-way valve 10 ensures unidirectional gas discharge and prevents external gas or molten material from flowing back into the installation space 502 during the exhaust process. The pressure detection device 11 monitors the air pressure in the molding space in real time and automatically triggers exhaust when the pressure exceeds the preset threshold, realizing the intelligent control of the exhaust process and improving production stability.

[0028] At the four corners of the upper end of the base 1, support columns 7 are fixedly connected. The upper ends of the support columns 7 are respectively fixedly connected to the four corners of the bottom of the top plate 3. The support columns 7 form a rigid frame structure, evenly bearing the vertical pressure of the mold during injection molding, avoiding deformation of the base 1 and the top plate 3, and ensuring the perpendicularity when the mold is closed and the alignment accuracy of the exhaust pipe 503.

[0029] Sliding rods 9 are fixedly connected to the four corners in the middle between the base 1 and the top plate 3. The middle parts on the left and right sides of the upper mold 4 are respectively slidably connected to the outer sides of the sliding rods 9. The sliding rods 9 provide linear guidance for the up and down movement of the upper mold 4, reduce the shaking and deviation during the movement, ensure the precise alignment of the forming block 5 and the forming groove 201, avoid the misalignment or poor sealing of the exhaust pipeline 503 caused by the mold closing deviation, and at the same time enhance the overall rigidity of the mold and improve the movement stability.

[0030] The implementation principle of the embodiment of this application is as follows: First, the hydraulic cylinder 8 pushes the upper mold 4 and the forming block 5 downward. The left and right sides of the upper mold 4 slide on the outer sides of the sliding rods 9, and the forming block 5 is pushed into the forming groove 201 for injection molding. Then, the gas generated during the injection molding process enters through the intake pipeline 501. At the same time, the pressure detection device 11 outside the intake pipeline 501 monitors the air pressure in the forming space 502 in real time. When the pressure exceeds the preset threshold, a start signal is sent to the micro cylinder 601. Secondly, the telescopic end of the micro cylinder 601 pushes the plug 605 to move inward, and the slider 606 slides along the chute 607, so that the plug 605 is separated from the blocking position of the intake pipeline 501, and the gas enters the inside of the installation space 502 from the forming space through the intake pipeline 501. Finally, the gas is discharged through the exhaust pipeline 503 under the action of pressure, and the check valve 10 outside it prevents the external gas from flowing back, ensuring the uniqueness of the exhaust direction.

[0031] The embodiments of this specific implementation manner are all preferred embodiments of this application, and do not limit the protection scope of this application accordingly. The same components are represented by the same reference numerals. Therefore, all equivalent changes made according to the structure, shape, and principle of this application should be covered within the protection scope of this application.

Claims

1. An exhaust device for an injection mold, comprising a base (1) and a top plate (3), characterized in that: The upper part of the base (1) is fixedly provided with a lower mold (2). The upper part of the lower mold (2) is provided with a forming groove (201). Both the left and right sides of the bottom of the top plate (3) are fixedly connected with hydraulic cylinders (8). The telescopic ends of the hydraulic cylinders (8) are fixedly connected with upper molds (4). The bottom of the upper mold (4) is fixedly provided with a forming block (5). The forming block (5) fits with the forming groove (201). Both the left and right sides of the inside of the forming block (5) are provided with installation spaces (502). Exhaust units (6) are arranged inside the installation spaces (502). The bottoms of the installation spaces (502) are both communicated with intake pipes (501). The intake pipes (501) are distributed through the left and right sides of the bottom of the forming block (5). The upper parts of the installation spaces (502) are both communicated with exhaust pipes (503). The exhaust pipes (503) are distributed through the middle parts of the left and right sides of the forming block (5).

2. The exhaust device of an injection mold according to claim 1, wherein: The exhaust units (6) each include a micro cylinder (601). The telescopic ends of the micro cylinders (601) are fixedly connected with plug blocks (605). The bottoms of the plug blocks (605) respectively block the upper parts of the corresponding intake pipes (501).

3. An exhaust device for an injection mold according to claim 2, characterized in that: Sealing rubber plates (602) are arranged on the outer sides of the telescopic ends of the micro cylinders (601). Springs (603) are arranged on the outer sides of the sealing rubber plates (602). Connection sleeves (604) are arranged on the upper parts of the sealing rubber plates (602). The telescopic ends of the micro cylinders (601) are respectively slidably connected to the inner sides of the corresponding connection sleeves (604).

4. An exhaust device for an injection mold according to claim 2, characterized in that: Sliders (606) are arranged at the upper ends of the plug blocks (605). Chute grooves (607) are arranged at the upper parts of the installation spaces (502). The sliders (606) are respectively slidably connected to the inner sides of the corresponding chute grooves (607). Limit blocks (608) are fixedly connected to the inner ends of the installation spaces (502).

5. An exhaust device for an injection mold according to claim 1, characterized in that: Check valves (10) are installed on the outer sides of the exhaust pipes (503). Pressure detection devices (11) are arranged on the outer sides of the intake pipes (501).

6. The exhaust device of an injection mold according to claim 1, characterized in that: Support columns (7) are fixedly connected to the four corners of the upper end of the base (1). The upper ends of the support columns (7) are respectively fixedly connected to the four corners of the bottom of the top plate (3).

7. An exhaust device for an injection mold according to claim 1, characterized in that: Slide rods (9) are fixedly connected to the four corners in the middle between the base (1) and the top plate (3). The middle parts of the left and right sides of the upper mold (4) are respectively slidably connected to the outer sides of the slide rods (9).

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