Suction and exhaust device of injection mold and using method of suction and exhaust device

Abstract

The invention discloses a suction exhaust device of an injection mold and a using method thereof, and relates to the technical field of injection molds, the suction exhaust device comprises the injection mold, an exhaust channel is arranged on the side wall of the injection mold, a driving mechanism communicates with the exhaust channel, a negative pressure plugging mechanism comprises a plugging cover, a lifting pipe is fixedly connected to the bottom end of the plugging cover, and an upper magnet is arranged at the bottom end of the lifting pipe; a lower magnet is arranged below the upper magnet, the opposite sides of the upper magnet and the lower magnet are opposite in magnetism, and a telescopic unlocking mechanism is arranged between the lifting pipe and the exhaust channel. Hot-melt plastic can rapidly flow into the injection mold cavity under the negative pressure effect, the negative pressure blocking mechanism is assembled at the port position of the exhaust channel, the negative pressure blocking mechanism is driven to be closed under the negative pressure effect, communication between the injection mold cavity and the exhaust channel is isolated, and therefore the injection mold is prevented from being blocked. And hot melt plastic is prevented from being pressed into the exhaust channel to cause blockage of the exhaust channel, so that the injection molding quality and efficiency of plastic products are improved.

Description

Technical Field

[0001] This invention relates to the field of injection mold technology, and in particular to a suction and venting device for injection molds and its usage method. Background Technology

[0002] Injection molds are core tools for the mass production of plastic products. They impart specific shapes, precise dimensions, and surface structures to molten plastic, and obtain the final product through cooling and solidification. The molding process involves rapidly injecting hot-melt plastic into the mold cavity using an injection molding machine. After cooling, the product is ejected. During the injection process, air is inherently present within the mold cavity. The key is to quickly expel this air, ensuring the plastic is injected into every corner of the cavity as quickly as possible to form a full and qualified product.

[0003] In current technology, most injection molds use passive venting to remove air from the mold cavity. This involves injecting molten plastic into the mold cavity to compress the space and expel the air. However, this method is prone to the following problems: The venting channels of the mold are easily blocked by hot melt plastic, requiring frequent manual cleaning, which increases the workload of manual labor. When the venting channel is blocked, the venting is not smooth, and the cavity of the injection mold cannot be filled, resulting in the product being out of size. Poor venting of the injection mold can cause the product tail to burn and result in poor appearance. It can also easily cause air bubbles inside the product and air marks on the product surface, affecting the quality of the molded product. Therefore, to improve the venting within the injection mold cavity, ensuring the hot-melt plastic fills the cavity and thus enhancing the quality of the molded plastic product, we propose a suction venting device for injection molds and its usage method. This device is particularly suitable for multi-cavity injection molding of bottle caps and preforms. Summary of the Invention

[0004] The purpose of this invention is to provide a suction and venting device for injection molds and its usage method, so as to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a suction and venting device for an injection mold, comprising: The injection mold has an inwardly extending venting channel on its side wall that communicates with the inner cavity of the injection mold. The drive mechanism is connected to the exhaust channel at one end and controls the flow of gas in the exhaust channel to keep the injection mold cavity under positive or negative pressure. The negative pressure sealing mechanism includes a sealing cover coaxially arranged with the exhaust channel port and capable of axial movement. A lifting tube is coaxially fixedly connected to the bottom end of the sealing cover. An upper magnet is coaxially provided at the bottom end of the lifting tube. A lower magnet fixed to the exhaust channel is provided below the upper magnet. The upper magnet and the lower magnet have opposite magnetic properties on opposite sides. A telescopic unlocking mechanism is provided between the lifting tube and the exhaust channel, so that the upper magnet moves down as the negative pressure increases until it is in contact with the lower magnet, which drives the telescopic unlocking mechanism to unlock, thereby causing the lifting tube and the sealing cover to move down to seal the exhaust channel port.

[0006] Preferably, the negative pressure sealing mechanism further includes: The port cylinder is fixedly connected to the port position of the exhaust channel, and the port position of the port cylinder and the outer peripheral wall position of the sealing cover are mutually adapted to each other in a frustum shape; The upper vent plate is fixedly connected to the top of the inner wall of the port cylinder. The outer wall of the lifting pipe is movably inserted into the middle of the upper vent plate. Both the upper vent plate and the lower magnet have vent holes all over their surfaces.

[0007] Preferably, the telescopic unlocking mechanism includes: The locking tongue is movably inserted into the top position of the outer peripheral wall of the lifting tube, and the inner side wall of the upper vent plate is provided with a locking hole that matches the locking tongue. A connecting rod is fixedly connected at its bottom end to the middle of the upper magnet. The outer wall of the connecting rod is slidably inserted into the inner cavity of the lifting tube, so that the connecting rod releases the push-out of the locking tongue and unlocks the device when the upper magnet moves down.

[0008] Preferably, the telescopic unlocking mechanism further includes a locking sleeve, which is fixedly inserted into the top of the lifting tube. The locking tongue is movably inserted into one end of the locking sleeve, and an unlocking rod is movably inserted into the other end of the locking sleeve. A first unlocking spring is provided between the unlocking rod and the locking tongue, and a second unlocking spring is provided between the unlocking rod and the end face of the locking sleeve.

[0009] Preferably, the drive mechanism includes: A vacuum valve is located on one side of the injection mold. A connecting hose is provided between one port of the vacuum valve and one end of the exhaust channel. A flange pipe for connecting to an external air source is fixedly installed at the other port of the vacuum valve. A solenoid valve is fixedly installed on the top of the vacuum valve to control the opening and closing of the vacuum valve.

[0010] Preferably, a connecting pipe seat is fixedly connected to the side wall of the injection mold at the position of the venting channel port. A fixed pipe head communicating with the venting channel port is fixedly connected inside the connecting pipe seat. A movable pipe head communicating with the connecting hose is inserted into one end of the fixed pipe head. A snap-fit ​​mechanism is provided at the end of the inner cavity of the connecting pipe seat near the movable pipe head to fix the docking position of the movable pipe head and the fixed pipe head.

[0011] Preferably, the snap-fit ​​mechanism includes: Two concave locking blocks are symmetrically arranged on both sides of the moving pipe head and move linearly along the inner wall of the connecting pipe seat. A sloping convex ring is fixedly connected to the outer wall of the moving pipe head. The sloping convex ring and the concave locking blocks are both sloping on the opposite side of the concave locking blocks. The combined screw has a drive box fixedly connected to the top of the connecting tube seat. The combined screw is located above the concave block and is rotatably connected to the inner wall of the drive box. Two traveling seats are symmetrically threaded on the combined screw, and the bottom ends of the two traveling seats are fixedly connected to the top of the concave block at the corresponding positions.

[0012] Preferably, rollers are rotatably connected to the opposite ends of the back of the two walking seats. A detection block that moves longitudinally along a straight line is provided on the top of the inner wall of the drive box. The surface of the detection block facing the rollers is inclined. A position switch is fixedly inserted into the back of the drive box. A detection lamp that is electrically connected to the position switch is fixedly connected to the top of the drive box. A detection spring is fixedly connected between the detection block and the inner wall of the back of the drive box.

[0013] Preferably, a probe rod is movably inserted into the side of the detection block facing the position switch, a U-shaped plate is movably inserted into the top of the detection block, and cylindrical slide rods are provided on both sides of the bottom of the U-shaped plate. An inclined channel fixedly connected to the side wall of the probe rod is movably inserted into the cylindrical slide rod. A cylindrical tube is fixedly connected to the top of the detection block, and a pressing rod is movably inserted into the cylindrical tube. The bottom end of the pressing rod is fixedly connected to the top of the U-shaped plate, and a return spring is fixedly connected between the top of the pressing rod and the bottom of the cylindrical tube.

[0014] On the other hand, the present invention also provides a method for using a suction and venting device for an injection mold, comprising the following steps: Before injection molding, the solenoid valve controls the vacuum valve to open, allowing the external vacuum pump to connect to the vacuum valve through the flange pipe. This allows for evacuation of the cavity inside the injection mold through the exhaust channel. As the gas inside the injection mold cavity is continuously extracted, the negative pressure increases, causing the upper magnet to move downwards and the gap between it and the lower magnet to shorten until they are in contact. At this point, the connecting rod separates from the end of the unlocking rod as the upper magnet moves downwards. The second unlocking spring drives the unlocking rod to move towards the inner cavity of the lifting tube. This causes the locking tongue to be pulled out from the locking hole inside the upper vent plate through the locking sleeve. This unlocks the lifting tube and the upper vent plate, causing the sealing cover to move downwards due to the negative pressure and close the port of the port cylinder, maintaining the negative pressure state inside the injection mold cavity. After injection molding, the solenoid valve controls the vacuum valve to open, and compressed air enters the exhaust channel of the injection mold through the flange pipe, vacuum valve and connecting hose, relieving the negative pressure in the exhaust channel. The magnetic thrust between the lower magnet and the upper magnet, as well as the airflow, pushes the upper magnet upward. The upper magnet then drives the lifting pipe and the sealing cover to move upward and reset, so that the locking tongue reaches the locking hole position on the upper vent plate and is inserted. This not only opens the port of the port cylinder, but also locks the opening position of the sealing cover, so that the port cylinder port will automatically move down and close after the subsequent injection mold cavity is formed under negative pressure.

[0015] The technical effects and advantages of this invention are as follows: This invention utilizes negative pressure to allow hot-melt plastic to flow more quickly into the injection mold cavity, while effectively ensuring that the cavity is filled. By installing a negative pressure sealing mechanism at the port of the venting channel, when the negative pressure in the injection mold cavity reaches a preset level, the mechanism is driven to close, sealing the port of the venting channel. This maintains the negative pressure in the injection mold cavity while isolating the cavity from the venting channel, preventing the hot-melt plastic from being forced into the venting channel and causing blockage, thus avoiding the need for manual cleaning and increasing workload. This improves the quality and efficiency of plastic injection molding. The negative pressure sealing mechanism provided by this invention utilizes the characteristic that the magnetic thrust between the upper and lower magnets is inversely proportional to the distance between them. This means that the higher the negative pressure in the exhaust channel, the smaller the distance between the upper and lower magnets. This ensures that the negative pressure in the exhaust channel reaches the required level when the upper and lower magnets are in contact. The upper magnet moves down to a preset position, which drives the telescopic unlocking mechanism to unlock the position of the lifting tube. This allows the sealing cover to automatically move down and close with the port of the port cylinder, thus sealing and isolating the injection mold cavity from the exhaust channel port. This automatically prevents hot melt plastic from being pressed into the exhaust channel port and sticking, causing blockage and increasing the complexity of subsequent cleaning. This improves the protection of the exhaust channel port and the efficiency of the injection mold. This invention, by adding a connecting pipe seat and a snap-fit ​​mechanism within the connecting pipe seat to the venting channel port on the side wall of the injection mold, enables quick installation between the moving pipe head at one end of the connecting hose and the fixed pipe head at the other end of the venting channel, improving assembly convenience and efficiency. Simultaneously, it allows for real-time monitoring of the tightness between the moving and fixed pipe heads, automatically providing feedback on the seal through a detection light. This eliminates the tediousness and uncertainty of manual inspection, making the connection between the drive mechanism and the injection mold more convenient and stable. Attached Figure Description

[0016] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention, but do not constitute a limitation thereof. In the drawings: Figure 1 This is a three-dimensional structural diagram of the present invention.

[0017] Figure 2 This is a partial cross-sectional structural diagram of the venting channel on the injection mold of the present invention.

[0018] Figure 3 This is a partial cross-sectional view of the rising pipe of the present invention.

[0019] Figure 4 This is a three-dimensional structural diagram of the connecting pipe seat of the present invention.

[0020] Figure 5 This is a top sectional view of the connecting pipe seat of the present invention.

[0021] Figure 6 This is a top sectional view of the drive box of the present invention.

[0022] Figure 7 This is a side cross-sectional view of the detection block of the present invention.

[0023] In the attached diagram: 100, injection mold; 101, venting channel; 102, port cylinder; 103, sealing cap; 104, lifting pipe; 105, upper vent plate; 106, lower magnet; 107, upper magnet; 108, connecting rod; 109, locking sleeve; 110, locking tongue; 111, unlocking rod; 112, first unlocking spring; 113, second unlocking spring; 200, drive mechanism; 201, vacuum valve; 202, solenoid valve; 203, flange pipe; 204, connecting hose; 2 05. Connecting pipe seat; 206. Fixed pipe head; 207. Moving pipe head; 208. Sloping convex ring; 209. Concave locking block; 210. Drive box; 211. Combined screw; 212. Traveling seat; 213. Roller; 214. Detection block; 215. Detection spring; 216. Position switch; 217. Detection light; 218. Detector rod; 219. Cylindrical tube; 220. U-shaped plate; 221. Inclined channel; 222. Cylindrical slide rod; 223. Return spring; 224. Pressing rod. Detailed Implementation

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] This invention provides, for example Figures 1-7 The image shows a suction and venting device for an injection mold.

[0026] Example 1: Includes an injection mold 100, with an inwardly extending venting channel 101 on its side wall communicating with the internal cavity of the injection mold 100. A negative pressure sealing mechanism is installed at the port of the venting channel 101, which automatically seals the port of the venting channel 101 when the negative pressure value in the mold cavity reaches a preset value. The negative pressure sealing mechanism includes a port cylinder 102, which is fixedly connected to the port of the venting channel 101. A sealing cover 103 that can move vertically to close or open the port of the port cylinder 102 is provided at the port of the port cylinder 102. A negative pressure detection mechanism is set at the lower port of the port cylinder 102 to detect the negative pressure. When the negative pressure in the port cylinder 102 reaches a preset value, it drives the sealing cover 103 to move down and seal the upper port of the port cylinder 102. In this embodiment, the cavity inside the injection mold 100 is connected to the outside via the exhaust channel 101. This allows gas to be introduced into or expelled from the cavity of the injection mold 100 through the exhaust channel 101. During the hot-melt plastic shaping process, the air inside the cavity of the injection mold 100 is extracted, creating a negative pressure. This negative pressure allows the hot-melt plastic to flow into the cavity more quickly, effectively ensuring that the cavity is filled completely. Compared to traditional passive venting methods, the injection process of hot-melt plastic into the cavity of the injection mold 100 is more efficient and smoother, and the cavity is filled more fully. Furthermore, by installing a negative pressure sealing mechanism at the port of the exhaust channel 101, when the negative pressure in the cavity of the injection mold 100 reaches a preset level, the mechanism can be activated to seal the cavity. The negative pressure is applied and driven to close the negative pressure sealing mechanism, thus sealing the port of the exhaust channel 101. This maintains the negative pressure state of the injection mold 100 cavity while isolating the cavity from the exhaust channel 101, preventing hot melt plastic from being forced into the exhaust channel 101 after being injected into the cavity, causing blockage and requiring manual cleaning, which would increase the workload. When the negative pressure in the injection mold 100 cavity reaches a preset level, the negative pressure detection mechanism detects the negative pressure state and drives the sealing cover 103 to move downward, so that the sealing cover 103 engages with the port of the port cylinder 102, thereby sealing the port of the exhaust channel 101. This automatically seals or opens the port of the exhaust channel 101 according to the negative pressure state, effectively preventing the hot melt plastic fluid from sticking and blocking the exhaust channel 101.

[0027] The negative pressure detection mechanism includes a lower magnet 106 and a telescopic unlocking mechanism. Its outer wall is covered with vent holes for airflow. The lower magnet 106 is fixedly installed at the bottom of the inner cavity of the port cylinder 102. An upper magnet 107 is coaxially arranged above the lower magnet 106. The lower magnet 106 and the upper magnet 107 are magnetic pole surfaces on opposite sides and repel each other. The telescopic unlocking mechanism is located between the sealing cover 103 and the upper magnet 107. The upper magnet 107 moves down to a position where it fits with the lower magnet 106, which drives the telescopic unlocking mechanism to open, allowing the sealing cover 103 to move down and seal the port of the port cylinder 102. The negative pressure within the cavity of the injection mold 100 is transmitted to the upper magnet 107, driving it to move downwards. The repulsive force between the like poles of the upper magnet 107 and the lower magnet 106 obstructs this downward movement. When the negative pressure within the cavity of the injection mold 100 reaches a preset level, the downward force on the upper magnet 107 gradually increases, causing it to move downwards until it comes into contact with the lower magnet 106. At this point, the negative pressure within the cavity of the injection mold 100 meets the preset condition, and the upper magnet 107 moves to the unlocking position of the telescopic unlocking mechanism. This releases the locking mechanism from the downward movement of the sealing cap 103. The sealing cap 103 then uses the negative pressure to move downwards and engage with the port of the port cylinder 102, ensuring a tight seal between the sealing cap 103 and the port cylinder 102. In the closed state, the sealing effect of the exhaust channel 101 port is ensured; when the negative pressure state in the cavity of the injection mold 100 and the exhaust channel 101 is released and compressed air is introduced into the exhaust channel 101, the magnetic thrust between the lower magnet 106 and the upper magnet 107, combined with the air pressure, causes the upper magnet 107 to move upward and gradually return to the initial position. During this process, the upper magnet 107 pushes the sealing cover 103 upward and returns the telescopic unlocking mechanism to the locked state, locking the position of the sealing cover 103 for subsequent negative pressure operation of the injection mold 100 cavity. In this way, the sealing or opening of the exhaust channel 101 port can be controlled according to the negative pressure state of the injection mold 100 cavity, avoiding the disadvantage of fluid adhering to the exhaust channel 101 and causing blockage; ventilation holes are provided on both the upper vent plate 105 and the lower magnet 106 to allow gas to flow in the exhaust channel 101.

[0028] The telescopic unlocking mechanism includes an upper vent plate 105, which is fixedly connected to the top of the inner cavity of the port cylinder 102. A lifting tube 104, which slides into the upper vent plate 105, is fixedly connected to the bottom of the sealing cover 103. A horizontally retractable locking tongue 110 is movably provided on the top of the outer wall of the lifting tube 104. A locking hole adapted to the locking tongue 110 is provided on the inner wall of the upper vent plate 105. The bottom of the connecting rod 108 is fixedly connected to the middle of the upper magnet 107. The outer wall of the connecting rod 108 is connected to the lifting tube 104. The inner cavity of tube 104 is slidably inserted, so that when the connecting rod 108 moves down with the upper magnet 107, it releases the push-out of the locking tongue 110 to unlock it. The locking sleeve 109 is fixedly inserted into the top of the lifting tube 104. The locking tongue 110 is movably inserted into one end of the locking sleeve 109. The other end of the locking sleeve 109 is movably inserted into the unlocking rod 111. A first unlocking spring 112 is provided between the unlocking rod 111 and the locking tongue 110. A second unlocking spring 113 is provided between the unlocking rod 111 and the end face of the locking sleeve 109. The top sidewall of the connecting rod 108 is a sloping surface, and one end of the unlocking rod 111 is flat, the other end is trapezoidal, and the middle is rod-shaped. This allows it to cooperate with the sidewall of the connecting rod 108 to form a pressing drive, enabling the connecting rod 108 to laterally push or release the unlocking rod 111 during vertical lifting. Simultaneously, the shape of the unlocking rod 111 also accommodates the installation of the first unlocking spring 112 and the second unlocking spring 113. After the unlocking rod 111 is positioned, the locking tongue 110 can further extend and retract within the locking sleeve 109 using the first unlocking spring 112. Furthermore, after the connecting rod 108 releases its obstruction of the unlocking rod 111, the second unlocking spring 113 drives the unlocking rod 111 to extend into the inner cavity of the lifting tube 104, simultaneously moving the first unlocking spring 112 and the locking tongue 110, allowing the locking tongue 110 to retract into the locking sleeve 109. Thus, the connecting rod 108... After the obstruction of the unlocking rod 111 is released, the locking tongue 110 can exit from the lock hole on the upper vent plate 105, releasing the lock between the lifting tube 104 and the upper vent plate 105. During the process of the connecting rod 108 moving upward to compress and block the unlocking rod 111, the locking tongue 110 can be further compressed into the locking sleeve 109 after contacting the upper vent plate 105, until 11 moves to the lock hole position on the upper vent plate 105 and then pops out. In this way, the lifting tube 104 can be unlocked when the connecting rod 108 moves downward. When the connecting rod 108 drives the lifting tube 104 to move upward, the locking tongue 110 on the side wall of the lifting tube 104 can automatically insert and lock with the lock hole on the upper vent plate 105. Thus, the telescopic unlocking mechanism can satisfy the automatic unlocking of the lifting tube 104 position when the upper magnet 107 moves downward and the automatic locking of the lifting tube 104 position when the upper magnet 107 moves upward.

[0029] Furthermore, the drive mechanism 200 is connected to the port of the exhaust channel 101 near the side wall of the injection mold 100, and is used to control the discharge or filling of gas in the cavity of the injection mold 100. The drive mechanism 200 includes a vacuum valve 201 and a solenoid valve 202. The vacuum valve 201 is located on one side of the injection mold 100. A connecting hose 204 is provided between one port of the vacuum valve 201 and one end of the exhaust channel 101. A flange pipe 203 for connecting to an external gas source is fixedly installed on the other port of the vacuum valve 201. The solenoid valve 202 is fixedly installed on the top of the vacuum valve 201 to control the opening and closing of the vacuum valve 201. The connection and cooperation of vacuum valve 201, solenoid valve 202 and exhaust channel 101 on injection mold 100 enable solenoid valve 202 to control the opening and closing of vacuum valve 201. Vacuum valve 201 is then connected to an external air source through flange pipe 203, which can control the evacuation or venting operation in exhaust channel 101. Since exhaust channel 101 is connected to the cavity of injection mold 100, the gas in the cavity of injection mold 100 can be discharged to form a negative pressure state before injection, so that hot melt plastic fluid can be injected into the cavity of injection mold 100 more efficiently. When inflating, it can help to eject the molded product from the cavity of injection mold 100, and at the same time clean the inner wall of exhaust channel 101, improving the efficiency of injection molding.

[0030] Example 2: Based on Example 1, a connecting pipe seat 205 is fixedly connected to the side wall of the injection mold 100 at the port of the venting channel 101. A fixed pipe head 206 communicating with the port of the venting channel 101 is fixedly connected inside the connecting pipe seat 205. A movable pipe head 207 communicating with the connecting hose 204 is inserted into one end of the fixed pipe head 206. A snap-fit ​​mechanism is provided at the end of the connecting pipe seat 205 near the movable pipe head 207 to fix the docking position of the movable pipe head 207 and the fixed pipe head 206. The moving pipe head 207 and the fixed pipe head 206 are configured as separate plug-in structures, and the plug-in state between the two is squeezed and fixed by the snap-fit ​​mechanism, thereby ensuring the stability of the plug-in state between the moving pipe head 207 and the fixed pipe head 206. This not only ensures the airtightness of the connection, but also facilitates the disassembly and replacement between the exhaust channel 101 and the fixed pipe head 206.

[0031] The locking mechanism includes two concave locking blocks 209 and a combined screw 211. The two concave locking blocks 209 are symmetrically arranged on both sides of the moving pipe head 207 and move linearly along the inner wall of the connecting pipe seat 205. A sloped convex ring 208 is fixedly connected to the outer wall of the moving pipe head 207. The sloped convex ring 208 and the concave locking blocks 209 are both sloped on the opposite side. The top of the connecting pipe seat 205 is fixedly connected to the drive box 210. The combined screw 211 is located above the concave locking blocks 209 and is rotatably connected to the inner wall of the drive box 210. Two traveling seats 212 are symmetrically threaded on the combined screw 211. The bottom of the two traveling seats 212 is fixedly connected to the top of the concave locking blocks 209 at the corresponding positions. The combined screw 211 rotates clockwise or counterclockwise to drive the two traveling seats 212 to move synchronously in opposite directions, thereby causing the two concave locking blocks 209 to translate towards the side wall of the moving tube head 207. Utilizing the slope between the contact surface of the convex ring 208 and the concave locking block 209, a thrust is provided to the moving tube head 207 in the same direction as the fixed tube head 206, creating a squeezing effect between the moving tube head 207 and the fixed tube head 206. Furthermore, as the translational position of the concave locking block 209 changes, the squeezing force between the moving tube head 207 and the fixed tube head 206 can be adjusted, facilitating control of the insertion and fixing state between the moving tube head 207 and the fixed tube head 206. In other embodiments, an elastic element can be added between the concave locking block 209 and the inner wall of the connecting tube seat 205 to assist the concave locking block 209 in moving towards the moving tube head 207.

[0032] Furthermore, rollers 213 are rotatably connected to the opposite ends of the back of the two walking seats 212. A detection block 214 that moves longitudinally along a straight line is provided on the top of the inner wall of the drive box 210. The surface of the detection block 214 facing the rollers 213 is inclined. A position switch 216 is fixedly inserted into the back of the drive box 210. A detection light 217 that is electrically connected to the position switch 216 is fixedly connected to the top of the drive box 210. A detection spring 215 is fixedly connected between the detection block 214 and the inner wall of the back of the drive box 210. The placement of the detection block 214 and the detection spring 215, along with the roller 213 mounted on the protruding part of the solenoid valve 202, allows the traveling seat 212 to synchronously push the detection block 214 back and forth during translation. This ensures that the concave locking block 209 presses the convex ring 208 into place, while the detection block 214 is driven by the traveling seat 212 to contact and press against the position switch 216. This closes the position switch 216, connecting the detection light 217 to the power supply. The illumination of the detection light 217 indicates that the tightness between the moving pipe head 207 and the fixed pipe head 206 meets the requirements, confirming the sealing between them. This eliminates the need for the user to perform assembly... During the process, there is concern that the sealing between the fixed pipe head 206 and the moving pipe head 207 may not meet the required level. At the same time, it can also detect whether there is any looseness between the fixed pipe head 206 and the moving pipe head 207. If the position of the combined screw 211 and the traveling seat 212 changes due to vibration during operation, it will be transmitted to the concave surface locking block 209 and cause it to loosen its pressure on the slope convex ring 208. This will change the pushing position of the traveling seat 212 on the detection block 214, and the detection block 214 will be disconnected from the position switch 216, causing the detection light 217 to go out. This allows the user to check the sealing between the fixed pipe head 206 and the moving pipe head 207 by checking whether the detection light 217 is on or off during maintenance.

[0033] Furthermore, a probe rod 218 is movably inserted into the side of the detection block 214 facing the position switch 216. A U-shaped plate 220 is movably inserted into the top of the detection block 214. A cylindrical slide rod 222 is provided on both sides of the bottom of the U-shaped plate 220. An inclined channel 221 fixedly connected to the side wall of the probe rod 218 is movably inserted into the cylindrical slide rod 222. A cylindrical tube 219 is fixedly connected to the top of the detection block 214. A pressing rod 224 is movably inserted into the cylindrical tube 219. The bottom end of the pressing rod 224 is fixedly connected to the top of the U-shaped plate 220. A return spring 223 is fixedly connected between the top of the pressing rod 224 and the bottom of the cylindrical tube 219. Sometimes, the detection light 217 fails to illuminate due to a malfunction of the position switch 216 or the detection light 217. Users cannot determine whether the extinguishing of the detection light 217 is caused by a loose connection between the fixed pipe head 206 and the moving pipe head 207. In such cases, pressing the pressing rod 224 moves the U-shaped plate 220 downwards. Simultaneously, the U-shaped plate 220, through the cylindrical sliding rod 222, exerts a squeezing effect on the inclined channel 221, causing it to move horizontally. This causes the probe rod 218 to extend from the detection block 214, allowing it to contact and press against the position switch 216 independently. The user can then determine whether the extinguishing of the detection light 217 is due to a malfunction of the position switch 216 or the detection light 217 by checking whether the light illuminates. This eliminates the tedious process of repeated checks and allows for a one-button inspection of the airtightness between the fixed pipe head 206 and the moving pipe head 207.

[0034] A method for using a suction and venting device for an injection mold includes the following steps: Before injection molding, the solenoid valve 202 controls the vacuum valve 201 to open, so that the external vacuum pump is connected to the vacuum valve 201 through the flange pipe 203. In this way, the air in the cavity of the injection mold 100 can be evacuated through the exhaust channel 101. As the gas in the cavity of the injection mold 100 is continuously evacuated, the negative pressure continuously increases, causing the upper magnet 107 to move down and the distance between it and the lower magnet 106 to shorten until they are in contact. At this time, the connecting rod 108 separates from the end of the unlocking rod 111 as the upper magnet 107 moves down. The second unlocking spring 113 drives the unlocking rod 111 to move towards the inner cavity of the lifting tube 104. In this way, the locking tongue 110 is pulled out from the locking hole in the upper vent plate 105 through the connection of the locking sleeve 109 and the unlocking rod 111, thereby unlocking the lifting tube 104 and the upper vent plate 105. The sealing cover 103 moves down due to the negative pressure and closes the port of the port cylinder 102, maintaining the negative pressure state in the cavity of the injection mold 100. After injection molding, the solenoid valve 202 controls the vacuum valve 201 to open, and compressed air enters the exhaust channel 101 of the injection mold 100 through the flange pipe 203, the vacuum valve 201 and the connecting hose 204, releasing the negative pressure state in the exhaust channel 101. The magnetic thrust between the lower magnet 106 and the upper magnet 107 and the airflow action push the upper magnet 107 upward. The upper magnet 107 then drives the lifting pipe 104 and the sealing cover 103 to move upward and reset, so that the locking tongue 110 reaches the locking hole position on the upper vent plate 105 and is inserted. This not only opens the port of the port cylinder 102, but also locks the opening position of the sealing cover 103, so that the port cylinder 102 will automatically move down and close the port of the port cylinder 102 after the subsequent injection mold 100 cavity is in a negative pressure state for molding.

[0035] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A suction and venting device for an injection mold, characterized in that, include: The injection mold (100) has an inwardly extending venting channel (101) on its side wall that communicates with the inner cavity of the injection mold (100). The drive mechanism (200) is connected at one end to the exhaust channel (101) at the other end, and controls the flow direction of gas in the exhaust channel (101) so that the cavity of the injection mold (100) is in a positive or negative pressure state; The negative pressure sealing mechanism includes a sealing cover (103) that is coaxially arranged with the port of the exhaust channel (101) and can move axially. The bottom end of the sealing cover (103) is coaxially fixedly connected to a lifting tube (104). The bottom end of the lifting tube (104) is coaxially provided with an upper magnet (107). Below the upper magnet (107) is a lower magnet (106) that is fixed to the exhaust channel (101). The upper magnet (107) and the lower magnet (106) have opposite magnetic properties on opposite sides. A telescopic unlocking mechanism is provided between the lifting tube (104) and the exhaust channel (101) so that the upper magnet (107) moves down as the negative pressure increases until it is in contact with the lower magnet (106), which drives the telescopic unlocking mechanism to unlock and causes the lifting tube (104) and the sealing cover (103) to move down to seal the port of the exhaust channel (101).

2. The suction and venting device for an injection mold according to claim 1, characterized in that, The negative pressure sealing mechanism also includes: Port cylinder (102), the port cylinder (102) is fixedly connected to the port position of the exhaust channel (101), the port position of the port cylinder (102) and the outer peripheral wall position of the sealing cover (103) are mutually adapted to each other in a frustum shape; The upper vent plate (105) is fixedly connected to the top of the inner wall of the port cylinder (102). The outer wall of the lifting tube (104) is movably inserted into the middle of the upper vent plate (105). The surfaces of the upper vent plate (105) and the lower magnet (106) are covered with vent holes.

3. The suction and venting device for an injection mold according to claim 2, characterized in that, The telescopic unlocking mechanism includes: The locking tongue (110) is movably inserted into the top position of the outer peripheral wall of the lifting tube (104), and the inner side wall of the upper vent plate (105) is provided with a lock hole that matches the locking tongue (110). The connecting rod (108) is fixedly connected at its bottom end to the middle of the upper magnet (107). The outer wall of the connecting rod (108) is slidably inserted into the inner cavity of the lifting tube (104), so that the connecting rod (108) releases the push-out of the locking tongue (110) to unlock when the upper magnet (107) moves down.

4. The suction and venting device for an injection mold according to claim 3, characterized in that, The telescopic unlocking mechanism also includes a locking sleeve (109), which is fixedly inserted into the top of the lifting tube (104). The locking tongue (110) is movably inserted into one end of the locking sleeve (109), and the other end of the locking sleeve (109) is movably inserted into an unlocking rod (111). A first unlocking spring (112) is provided between the unlocking rod (111) and the locking tongue (110), and a second unlocking spring (113) is provided between the unlocking rod (111) and the end face of the locking sleeve (109).

5. The suction and venting device for an injection mold according to claim 4, characterized in that, The drive mechanism (200) includes: Vacuum valve (201) is located on one side of injection mold (100). A connecting hose (204) is provided between one end of the vacuum valve (201) and one end of the exhaust channel (101). A flange pipe (203) for connecting to an external air source is fixedly installed on the other end of the vacuum valve (201). Solenoid valve (202) is fixedly installed on the top of vacuum valve (201) to control the opening and closing of vacuum valve (201).

6. The suction and venting device for an injection mold according to claim 5, characterized in that, A connecting pipe seat (205) is fixedly connected to the side wall of the injection mold (100) at the port of the exhaust channel (101). A fixed pipe head (206) communicating with the port of the exhaust channel (101) is fixedly connected inside the connecting pipe seat (205). A movable pipe head (207) communicating with the connecting hose (204) is inserted into one end of the fixed pipe head (206). A snap-fit ​​mechanism is provided at the end of the inner cavity of the connecting pipe seat (205) near the movable pipe head (207) to fix the docking position of the movable pipe head (207) and the fixed pipe head (206).

7. The suction and venting device for an injection mold according to claim 6, characterized in that, The latching mechanism includes: Two concave locking blocks (209) are symmetrically arranged on both sides of the moving pipe head (207) and move linearly along the inner wall of the connecting pipe seat (205). A sloping convex ring (208) is fixedly connected to the outer wall of the moving pipe head (207). The sloping convex ring (208) and the concave locking blocks (209) are both sloping on the opposite side. The combined screw (211) has a drive box (210) fixedly connected to the top of the connecting tube seat (205). The combined screw (211) is located above the concave card block (209) and is rotatably connected to the inner wall of the drive box (210). Two walking seats (212) are symmetrically threaded on the combined screw (211). The bottom ends of the two walking seats (212) are fixedly connected to the top of the concave card block (209) at the corresponding positions.

8. The suction and venting device for an injection mold according to claim 7, characterized in that, Rollers (213) are rotatably connected to the opposite ends of the back of the two walking seats (212). A detection block (214) that moves longitudinally along a straight line is provided on the top of the inner wall of the drive box (210). The surface of the detection block (214) facing the roller (213) is inclined. A position switch (216) is fixedly inserted into the back of the drive box (210). A detection lamp (217) that is electrically connected to the position switch (216) is fixedly connected to the top of the drive box (210). A detection spring (215) is fixedly connected between the detection block (214) and the inner wall of the back of the drive box (210).

9. The suction and venting device for an injection mold according to claim 8, characterized in that, The detection block (214) has a probe rod (218) movably inserted into the side facing the position switch (216). A U-shaped plate (220) is movably inserted into the top of the detection block (214). A cylindrical slide rod (222) is provided on both sides of the bottom of the U-shaped plate (220). An inclined channel (221) fixedly connected to the side wall of the probe rod (218) is movably inserted into the cylindrical slide rod (222). A cylindrical tube (219) is fixedly connected to the top of the detection block (214). A pressing rod (224) is movably inserted into the cylindrical tube (219). The bottom end of the pressing rod (224) is fixedly connected to the top of the U-shaped plate (220). A return spring (223) is fixedly connected between the top of the pressing rod (224) and the bottom of the cylindrical tube (219).

10. A method of using the suction and venting device for an injection mold according to any one of claims 1-9, characterized in that, Includes the following steps: Before injection molding, the solenoid valve (202) controls the vacuum valve (201) to open, so that the external vacuum pump is connected to the vacuum valve (201) through the flange pipe (203). In this way, the air in the cavity of the injection mold (100) can be evacuated through the exhaust channel (101). As the gas in the cavity of the injection mold (100) is continuously extracted, the negative pressure continuously increases, causing the upper magnet (107) to move down and the distance between it and the lower magnet (106) to shorten until they are in contact. At this time, the connecting rod (108) moves down with the upper magnet (107) and engages with the unlocking rod (106). 11) The end is separated. The second unlocking spring (113) drives the unlocking rod (111) to move towards the inner cavity of the lifting tube (104). This causes the locking tongue (110) to move with the unlocking rod (111) through the connection of the locking sleeve (109) and be pulled out from the lock hole in the upper vent plate (105), thereby unlocking the lifting tube (104) and the upper vent plate (105). The sealing cover (103) moves downward due to the negative pressure and closes the port of the port cylinder (102), maintaining the negative pressure state in the cavity of the injection mold (100). After injection molding, the solenoid valve (202) controls the vacuum valve (201) to open. Compressed air enters the exhaust channel (101) of the injection mold (100) through the flange pipe (203), vacuum valve (201) and connecting hose (204), releasing the negative pressure state in the exhaust channel (101). The magnetic thrust between the lower magnet (106) and the upper magnet (107) and the airflow action push the upper magnet (107) upward. The upper magnet (107) then drives the lifting pipe (104) and the sealing cover (103) to move upward and reset, so that the locking tongue (110) reaches the locking hole position on the upper vent plate (105) and is inserted. This not only opens the port of the port cylinder (102), but also locks the opening position of the sealing cover (103), so that the port of the port cylinder (102) will automatically move down and close the port of the port cylinder (102) after the subsequent injection mold (100) cavity is formed under negative pressure.

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