An injection mold for precision control of a flow sealing valve

Abstract

The application discloses an injection mold for precisely controlling the flow of a sealing valve sheet, which comprises a mold frame, a lower mold, an upper mold and a lifting assembly, the lower mold is provided with a lower cavity and a first through hole, the upper mold is used for combining with the lower mold to form a forming mold, the forming mold is internally provided with a forming cavity and a rubber injection channel; the forming cavity comprises a product cavity and a flash cavity, the lower mold is further provided with a second through hole and a connecting channel, an adjusting rod is arranged in the second through hole, and a telescopic assembly for driving the adjusting rod to move is arranged below the lower mold; and the first through hole is used for connecting a vacuum pump. The injection mold for precisely controlling the flow of a sealing valve sheet controls the movement of the adjusting rod through the telescopic assembly, controls the communication and blockage of the first through hole and the second through hole, vacuums through the first through hole to exhaust the air in the forming cavity before injection, blocks the first through hole and the second through hole, continuously vacuums and injects rubber, ensures the fixed position of a metal insert, moves the adjusting rod upwards to extrude the rubber, increases the compactness, and finally improves the product quality.

Description

Technical Field

[0001] This invention relates to the field of sealing rubber injection molding technology, and in particular to an injection mold for a sealing valve plate for precise flow control. Background Technology

[0002] Precision flow control sealing valves are key components in hydraulic and pneumatic systems for controlling media flow and regulating flow. Their sealing performance and dimensional accuracy directly determine the system's control precision and operational reliability. These valves typically employ a composite structure where a metal insert is coated with rubber. During production, molten rubber is injected into the outer periphery of the metal insert cap using an injection mold, forming a one-piece molded structure.

[0003] However, in existing injection molds, when molten rubber is injected into the cavity under high pressure, it generates an upward buoyancy force on the metal insert. Traditional molds rely solely on the weight of the metal insert itself or simple lower mold steps for radial positioning, which cannot effectively counteract the buoyancy force. This easily leads to insert displacement and floating, ultimately affecting product quality. Furthermore, during the injection process, the incomplete expulsion of gas from the cavity easily creates air bubbles and shrinkage cavities within the rubber, resulting in limited rubber density and affecting the sealing performance and lifespan of the valve plate. Additionally, the fixed volume of the cavity within the injection mold prevents automatic adjustment and control of the injection pressure. Excessive injection pressure can lead to overflow at the parting surface and mold deformation, impacting subsequent production. Moreover, after injection molding, the cured rubber tends to adhere to the lower mold. Traditional injection molds typically use ejector pins to lift the product from the bottom of the metal insert. However, both the ejector pin and the metal insert are rigid components; when lifting the product, they collide, causing wear and affecting the final product quality.

[0004] Therefore, it is necessary to improve the injection molds for sealing valve plates in the existing technology. Summary of the Invention

[0005] The purpose of this invention is to overcome the defects in the prior art and provide an injection mold for a sealing valve plate for precise flow control, which ensures the fixed position of the metal insert during injection molding, increases the density of the rubber, can automatically adjust and control the pressure, and facilitates safe demolding.

[0006] To achieve the above technical effects, the technical solution of the present invention is as follows: an injection mold for a flow precision control sealing valve plate, comprising a mold frame, a lower mold, an upper mold, and a lifting assembly. The lower mold is disposed on the mold frame and has a lower cavity and a first through hole that are coaxially connected from top to bottom and have a vertical axis. The lower cavity is used to place the cap of a metal insert, and the first through hole is used to receive and radially position the rod of the metal insert. The upper mold is disposed on the mold frame through the lifting assembly and moves between a mold closing station and a mold parting station. The upper mold at the mold closing station is used to combine with the lower mold to form a molding mold. The molding mold has a built-in molding cavity and is provided with a glue injection channel communicating with the molding cavity. A material taking gap is provided between the upper mold and the lower mold at the mold parting station. The molding cavity includes a product cavity and a flash cavity that are connected. The lower mold is also provided with a second through hole with a vertical axis and the top of the flash cavity is connected to the bottom of the flash cavity, and a connecting channel connecting the first through hole and the second through hole. One end of the connecting channel connected to the second through hole is a conductive end. An adjusting rod is provided in the second through hole and sealed to its circumferential inner wall. A telescopic component is also provided below the lower mold. The telescopic component drives the adjusting rod to move in the vertical direction to control the connection and disconnection between the conductive end and the flash cavity. The first through hole is used to connect a vacuum pump.

[0007] Preferably, in order to ensure that there is no excess rubber material in the second through hole after injection molding, the movable positions of the adjusting rod include a guiding position, a closing position and a filling position distributed from bottom to top. The top of the adjusting rod in the guiding position is located below the guiding end, the top of the adjusting rod in the closing position is located between the guiding end and the bottom wall of the flash cavity, and the top of the adjusting rod in the filling position is flush with the bottom wall of the flash cavity.

[0008] Preferably, to facilitate mold production, the bottom surface of the upper mold is a horizontal plane, and the molding cavity is formed by the cavity wall of the lower cavity and the bottom surface of the upper mold.

[0009] Preferably, in order to reduce the amount of rubber used while ensuring that the molten rubber can fill the inside of the product cavity, the flash cavity is adjacent to the product cavity and the flash cavity is connected to the top of the product cavity.

[0010] Preferably, in order to ensure the safe execution of injection molding, the upper mold is connected to a pressure control component, which is used to automatically limit the rubber pressure in the molding cavity during injection molding.

[0011] Preferably, in order to achieve automatic limiting control of rubber pressure, the bottom and top surfaces of the upper mold are respectively provided with an axially vertical and interconnected third through hole and a receiving recess. The cross-sectional dimension of the receiving recess is larger than the cross-sectional dimension of the third through hole. The pressure control component includes a pressure control rod that slides vertically in the third through hole and a counterweight block fixed to the top of the pressure control rod and located in the receiving recess.

[0012] Preferably, in order to limit the range of motion of the pressure control component, the position of the range of motion of the pressure control component is the forming station. At the forming station, the bottom surface of the counterweight and the bottom surface of the pressure control rod are respectively in contact with the bottom wall of the recess and the bottom surface of the recess.

[0013] Preferably, in order to facilitate vacuuming inside the molding cavity, multiple molding cavities are provided and arranged sequentially and adjacently, with the flash cavities of adjacent molding cavities interconnected. The bottom surface of the lower mold is provided with a negative pressure recess, and the first through hole corresponding to each molding cavity is connected to the negative pressure recess. The negative pressure recess is fixedly covered with a bottom cover, and a vacuum tube for connecting a vacuum pump is opened on the bottom cover. The negative pressure recess and the bottom cover enclose a negative pressure cavity, and a negative pressure gauge is provided inside the negative pressure cavity.

[0014] Preferably, to facilitate demolding, the bottom cover is also connected to a branch pipe that communicates with the outside. The branch pipe is equipped with a switch valve. The movable position of the adjusting rod also includes a lifting position located above the leveling position, so as to lift the flying edge by adjusting the rod.

[0015] Preferably, in order to ensure that the cap of the metal insert can be fixed to the bottom of the lower cavity during injection molding and to ensure the molding accuracy of the final product, the bottom surface of the cap of the metal insert is sealed and fitted to the bottom cavity wall of the lower cavity, and the circumferential outer edge of the metal insert rod is sealed and fitted to the circumferential inner wall of the first through hole.

[0016] In summary, compared with the prior art, the injection mold for the flow precision control sealing valve plate of the present invention controls the movement of the adjusting rod through the telescopic component, thereby controlling the connection and blockage between the first and second through holes. Before injection molding, a vacuum is drawn through the first through hole to expel air from the molding cavity. Then, the first and second through holes are blocked. The vacuum is continuously drawn and rubber is injected to ensure that the position of the metal insert is fixed. The adjusting rod moves upward to compress the rubber, increasing the density and ultimately improving the product quality. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure when the product is removed according to the present invention; Figure 2 This is a schematic diagram of the structure of the present invention before and after mold closing; Figure 3 yes Figure 1 An explosion diagram; Figure 4 This is a partial structural diagram of the upper and lower molds of the present invention when they are closed. Figure 5 yes Figure 4 An explosion diagram; Figure 6 These are a schematic diagram and a front view of the metal insert used in this invention; Figure 7 yes Figure 4 Cross-sectional structural diagram; Figure 8 yes Figure 7 Enlarged view of part A; Figure 9 yes Figure 7 Enlarged view of part B; Figure 10 This is a schematic diagram of the upper mold structure of the present invention; Figure 11 yes Figure 10 An explosion diagram; Figure 12 This is a schematic diagram of the lower mold structure of the present invention; Figure 13 yes Figure 12 An explosion diagram; Figure 14 This is a cross-sectional structural diagram of the lower mold of the present invention; Figure 15 This is a cross-sectional view of the lower mold of the present invention from another perspective. Figure 16 yes Figure 15 Enlarged view of part C; In the diagram: 1. Mold frame; 11. Base; 111. Locking hole; 12. Slide rail; 13. Positioning baffle; 2. Lower mold; 201. Bottom plate; 2011. Lower guide post; 202. Pressure plate; 2021. Lower guide hole; 203. Lower bolt; 204. Lower nut; 21. Lower cavity; 211. Forming recess; 212. Flash groove; 22. First through hole; 221. First lower through hole; 222. First upper through hole; 23. Second through hole; 231. Second lower through hole; 232. Second upper through hole; 2 4. Connecting channel; 241. Lower connecting groove; 242. Upper connecting groove; 25. Adjusting rod; 26. Telescopic assembly; 261. Telescopic cylinder; 262. Moving frame; 263. Slide rod; 27. Negative pressure recess; 271. Negative pressure gauge; 28. Bottom cover; 281. Branch pipe; 282. Switch valve; 3. Upper mold; 301. Top plate; 3011. Upper through hole for glue injection; 3012. Upper groove for glue injection; 3013. Upper guide tube; 302. Pressure plate; 3021. Blind hole for glue injection; 3022. Lower groove for glue injection; 3023, Lower through hole for glue injection; 3024, Upper guide hole; 303, Upper bolt; 304, Upper nut; 31, Glue injection channel; 32, Pressure control component; 321, Pressure control rod; 322, Counterweight; 33, Third through hole; 331, Third lower through hole; 332, Third upper through hole; 34, Receiving recess; 4, Lifting assembly; 41, Fixing frame; 42, Lifting cylinder; 43, Lifting frame; 431, Lifting frame; 432, Connecting rod; 433, Crossbar; 434, Guide rod; 5, Metal insert; 51, Cap; 511, Top plate; 512, Connecting shaft; 513, Base; 52, Rod; 6, Sliding frame; 61, Slide plate; 611, Insertion hole; 62, Slide groove; 63, Handle; 64, Locking pin; 7, Support frame; 71, Support frame; 72, Column. Detailed Implementation

[0018] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings and examples. The following examples are only used to more clearly illustrate the technical solutions of the present invention and should not be construed as limiting the scope of protection of the present invention.

[0019] like Figures 1-16 As shown, an injection mold for a flow precision control sealing valve plate according to the present invention includes a mold frame 1, a lower mold 2, an upper mold 3, and a lifting assembly 4. The lower mold 2 is disposed on the mold frame 1 and has a lower cavity 21 and a first through hole 22 that are coaxially connected from top to bottom and have a vertical axis. The lower cavity 21 is used to place the cap 51 of the metal insert 5, and the first through hole 22 is used to receive and radially position the rod 52 of the metal insert 5. The upper mold 3 is disposed on the mold frame 1 through the lifting assembly 4 and moves between the mold closing station and the mold parting station. The upper mold 3 at the mold closing station is used to combine with the lower mold 2 to form a molding mold. The molding mold has a built-in molding cavity and is provided with an injection channel 31 that communicates with the molding cavity. A material taking gap is provided between the upper mold 3 and the lower mold 2 at the mold parting station. The molding cavity includes a product cavity and a flash cavity that are connected. The lower mold 2 is also provided with a second through hole 23 with a vertical axis and the top of the flash cavity is connected to the bottom of the flash cavity, and a connecting channel 24 connecting the first through hole 22 and the second through hole 23. One end of the connecting channel 24 connected to the second through hole 23 is a conductive end. An adjusting rod 25 is provided in the second through hole 23 and is sealed to its circumferential inner wall. A telescopic component 26 is also provided below the lower mold 2. The telescopic component 26 drives the adjusting rod 25 to move in the vertical direction to control the connection and disconnection between the conductive end and the flash cavity. The first through hole 22 is used to connect a vacuum pump.

[0020] When using the injection mold for this valve, after adjusting the upper mold 3 and the lower mold 2 to the material-receiving gap, a metal insert 5 is placed in the lower cavity 21 of the lower mold 2. The specific structure of the metal insert 5 is described in [reference needed]. Figure 6 It includes a cap 51 and a rod 52 that are fixedly connected by a coaxial centerline. The cap 51 includes a top plate 511, a connecting shaft 512, and a base plate 513, all of which are coaxial with the rod 52. The base plate 513 is integrally connected to the rod 52. The outer diameters of the rod 52, the connecting shaft 512, the base plate 513, and the top plate 511 increase sequentially. The two end faces of the base plate 513 and the two end faces of the top plate 511 are perpendicular to the centerline of the connecting shaft 512.

[0021] Insert the rod portion 52 of the metal insert 5 into the first through hole 22 of the lower mold 2, so that the bottom surface of the base 513 fits against the bottom cavity of the lower cavity 21. In this invention, the inner diameter of the first through hole 22 is the same as the outer diameter of the rod portion 52, so that the circumferential outer edge of the rod portion 52 of the metal insert 5 is sealed and fitted against the circumferential inner wall of the first through hole 22, thereby achieving radial positioning of the metal insert 5. After that, after aligning the lower mold 2 with the upper mold 3, the lifting component 4 operates, driving the upper mold 3 to descend until the bottom surface of the upper mold 3 fits against the top surface of the lower mold 2, that is, after the parting surface of the upper mold 3 and the parting surface of the lower mold 2 are on the same horizontal plane, the upper mold 3 and the lower mold 2 are combined to form a molding mold, at which time the upper mold 3 and the lower mold 2 enclose to form a molding cavity.

[0022] Then, the telescopic assembly 26 operates, controlling the axial position of the adjusting rod 25 so that it is below the conductive end. At this time, inside the lower mold 2, after the first through hole 22 is connected to the second through hole 23 through the connecting channel 24, the vacuum pump is started, and air is drawn from the first through hole 22 and maintained. In this way, the air in the product cavity and flash cavity is discharged to the outside through the second through hole 23, the connecting channel 24, and the first through hole 22 in sequence, thereby creating a vacuum state in the molding cavity of the molding mold. Afterward, the telescopic assembly 26 controls the adjusting rod 25 to move upward, so that the top of the adjusting rod 25 moves above the conductive end. The connecting channel 24 is closed, thereby isolating the first through hole 22 from the second through hole 23. In this state, the negative pressure formed in the first through hole 22 acts on the metal insert 5, causing the cap 51 of the metal insert 5 to abut against the bottom cavity wall of the lower cavity 21 to secure the position of the metal insert 5. Then, molten rubber is injected into the molding cavity through the injection channel 31. Since the metal insert 5 is attracted and secured by the negative pressure, the position of the metal insert 5 is prevented from shifting due to the force of the rubber, ensuring the molding accuracy of the product in the later stage, improving the coaxiality and sealing surface position accuracy of the product, and providing a structural basis for the precise flow control of the final product.

[0023] After the molten rubber fills the molding cavity, some of the rubber flows downward into the second through hole 23. After flowing to the top of the adjusting rod 25, the adjusting rod 25 moves upward through the telescopic component 26, causing the adjusting rod 25 to squeeze the rubber in the molding cavity upward, thereby increasing the density of the rubber in the molding cavity. Since the air in the molding cavity was previously discharged, the density of the rubber in the molding cavity is further increased, thereby significantly improving the sealing performance of the invention and extending its service life.

[0024] A further improvement is that the movable positions of the adjusting rod 25 include a conducting position, a closing position, and a leveling position distributed sequentially from bottom to top. The top of the adjusting rod 25 in the conducting position is located below the conducting end, the top of the adjusting rod 25 in the closing position is located between the conducting end and the bottom wall of the flash cavity, and the top of the adjusting rod 25 in the leveling position is flush with the bottom wall of the flash cavity.

[0025] After adopting the above design, after mold closing and before rubber injection, the adjusting rod 25 is moved to the through position via the telescopic component 26, so that the first through hole 22 is connected to the second through hole 23 through the connecting channel 24. Then, a vacuum pump is used to extract air from the first through hole 22, allowing the air in the molding cavity to be discharged sequentially through the second through hole 23, the connecting channel 24, and the first through hole 22, creating a vacuum environment in the molding cavity and significantly reducing the amount of air. Then, the adjusting rod 25 is moved to the closed position to seal the through end. The vacuum pump continues to run, maintaining the fixed position of the metal insert 5, and the rubber is injected through the injection channel 31. Molten rubber is injected into the mold cavity. Since a vacuum environment is formed in the molding cavity and the metal insert 5 is fixed by negative pressure, air is prevented from mixing into the molten rubber and forming pores. At the same time, the displacement of the metal insert 5 is prevented from affecting the quality of the final product. Some of the molten rubber flows down into the second through hole 23 through the flash cavity. Then, the adjusting rod 25 moves up to squeeze the rubber in the molding cavity, improve the rubber density, improve the molding quality of the final product and extend its service life. Before mold separation, the adjusting rod 25 moves to the leveling position so that the top of the adjusting rod 25 is flush with the bottom cavity wall of the flash cavity, so as to prevent rubber from remaining in the second through hole 23.

[0026] A further improvement is that the bottom surface of the upper mold 3 is a horizontal surface, and the molding cavity is formed by the cavity wall of the lower cavity 21 and the bottom surface of the upper mold 3.

[0027] With the above design, the structure is simplified. Only the lower mold 2 needs to be opened, so that the upper mold 3 and the lower mold 2 can be closed to form a molding cavity. More specifically, the lower cavity 21 of the lower mold 2 of the present invention includes a molding recess 211 and a flash groove 212. The flash groove 212 is an annular groove that connects to the outside of the molding recess 211. The first through hole 22 is coaxially connected to the bottom of the molding recess 211. The second through hole 23 is distributed in an annular array and connected to the bottom of the flash groove 212. The inner wall of the flash groove 212 and the bottom surface of the upper mold 3 enclose the flash cavity. The inner wall of the molding recess 211 and the bottom surface of the upper mold 3 enclose the product cavity.

[0028] To facilitate rapid filling of the molding cavity with rubber, the flash cavity is adjacent to the product cavity and the top of the flash cavity is connected to the top of the product cavity. This reduces the volume of the molding cavity. The injection channel 31 is connected to the product cavity, so that after the injected molten rubber enters the product cavity through the injection channel 31, it first fills the product cavity and then enters the flash cavity. More specifically, there is an annular groove connecting the molding recess 211 and the flash groove 212. The bottom of the groove and the groove opening are fitted with a gap. The groove is located between the top of the molding recess 211 and the top of the flash groove 212, which facilitates the molten rubber to enter the flash groove 212 through the groove after filling the molding cavity.

[0029] A further improvement is that the lower mold 2 is detachably mounted on the sliding frame 6, which slides horizontally between the pick-and-place station and the docking station. Below the pick-and-place station, as... Figure 1 As shown, the projection of the lower mold 2 on the horizontal plane is outside the projection of the lower mold 2 on the horizontal plane. At the docking station, as... Figure 2 As shown, the lower mold 2 is located directly above the upper mold 3, and the sliding frame 6 is connected to a locking component, which is used to lock the sliding frame 6 to the pick-up and drop-off station and the docking station.

[0030] With the above design, the position of the sliding frame 6 can be easily locked and fixed by the locking component, so that the lower mold 2 is fixed at the pick-up and put-down station. At this station, it is convenient to take out the product. At the docking station, it is convenient for the upper mold 3 to close with the lower mold 2 through the lifting component 4, forming a mold as shown in the figure. Figure 4 The structure shown.

[0031] Specifically, such as Figure 3 As shown, the mold frame 1 includes a base 11, which is a horizontal rectangular plate. A slide rail 12 extending along the length of the base 11 is fixed on the base 11, and positioning baffles 13 are fixed at both ends of the slide rail 12. The sliding frame 6 includes a horizontal slide plate 61. A groove 62 that slides and engages with the slide rail 12 is provided below the slide plate 61. A handle 63 is fixed at one end of the slide plate 61. The handle 63 facilitates the movement of the slide plate 61 along the length of the base 11 under the sliding engagement of the groove 62 and the slide rail 12. The base 11 also has two locking holes 1 distributed along its length. 11. The slide plate 61 is provided with an insertion hole 611 and a locking pin 64. The insertion hole 611 is engaged with one of the locking holes 111 through the locking pin 64. Specifically, in the delivery station, one side of the slide plate 61 abuts against one of the positioning baffles 13 and the coaxial center line of the insertion hole 611 is located above one of the locking holes 111. In the docking station, the other side of the slide plate 61 abuts against another positioning baffle 13 and the coaxial center line of the insertion hole 611 is located above another locking hole 111. In this way, it is convenient to lock the position of the slide plate 61 so as to lock the lower mold 2 in the delivery station or the docking station.

[0032] A further improvement is that multiple molding cavities are arranged sequentially and adjacent to each other, and the flash cavities of adjacent molding cavities are interconnected. The bottom surface of the lower mold 2 is provided with a negative pressure recess 27. The first through hole 22 corresponding to each molding cavity is connected to the negative pressure recess 27. The negative pressure recess 27 is fixedly covered with a bottom cover 28. A vacuum tube for connecting a vacuum pump is opened on the bottom cover 28. The negative pressure recess 27 and the bottom cover 28 enclose a negative pressure cavity, and a negative pressure gauge 271 is provided in the negative pressure cavity.

[0033] With the above design, it is convenient to form multiple molding cavities after the upper mold 3 and the lower mold 2 are closed, which facilitates the production of multiple products at one time, improves production efficiency, and the negative pressure gauge 271 can be used to conveniently detect the negative pressure in each molding cavity before injection molding, so as to cooperate with the telescopic component 26 to control the adjusting rod 25 to move axially.

[0034] Specifically, such as Figures 12-16 As shown, in this invention, the lower mold 2 is provided with six rows of forming units distributed along the length direction of the base 11. Each forming unit includes twelve lower cavities 21 distributed along the width direction of the base 11. The flash grooves 212 of two adjacent lower cavities 21 are connected and close to each other to ensure the structural compactness of the device and reduce the space occupied. The number of forming units is equal to and corresponds to the number of negative pressure recesses 27, vacuum tubes, and negative pressure gauges 271. Thus, the vacuum degree of the above seventy-two forming cavities can be monitored by only six negative pressure gauges 271.

[0035] A further improvement is that the bottom cover 28 is also connected to a branch pipe 281 that communicates with the outside. A switch valve 282 is installed on the branch pipe 281. The movable position of the adjusting rod 25 also includes a lifting position located above the leveling position, so as to lift the flying edge by adjusting the rod 25.

[0036] Specifically, branch pipe 281 is fixedly connected to vacuum pipe. Before injection molding, switch valve 282 on branch pipe 281 is closed, isolating the negative pressure chamber from the outside. Vacuum pump expels air from the molding cavity through the negative pressure chamber, reducing air content and increasing rubber density during injection molding. After injection molding, switch valve 282 is opened, allowing the first through hole 22 to connect with the outside through the negative pressure chamber, preventing the metal insert 5 from being adsorbed and fixed on the lower mold 2. Then, telescopic component 26 drives adjusting rod 25 to move up to the lifting position. At this time, the top of adjusting rod 25 is above the bottom of flash groove 212, and during the upward movement, it acts on the flash of the product, not on the molding. Compared to the traditional method of rigidly contacting the rod 52 of the metal insert 5, the adjustment rod 25 of this invention contacts the rubber flash to transmit the lifting pressure to the product. Therefore, it will not cause wear to the metal insert 5 and the adjustment rod 25, thus extending the service life of the mold and avoiding wear caused by rigid collisions to the metal insert 5. In addition, the adjustment rod 25 is distributed in a ring array outside the first through hole 22, ensuring that the lifting force is evenly applied to the entire rubber mass, rather than concentrated in a local position of the insert. In this way, scratches and wear on the metal insert 5 in the product are avoided, providing a reliable foundation for subsequent precision assembly and high-precision flow control.

[0037] A further improvement is that a support frame 7 is fixed on the slide plate 61, and the lower mold 2 is detachably mounted on the support frame 7, which facilitates the replacement and maintenance of the lower mold 2.

[0038] More specifically, such as Figure 5 , Figures 12-16 As shown, in this invention, the support frame 7 includes a horizontal support frame 71 and vertically arranged pillars 72 that are spaced apart circumferentially along the support frame 71. The bottom of the pillars 72 is fixed to the slide plate 61.

[0039] The lower mold 2 includes a bottom plate 201 and a pressure plate 202 that are horizontally arranged from top to bottom. The four corners of the bottom plate 201 and the four corners of the pressure plate 202 are detachably fixed to the upper part of the support frame 71 by threaded bolts 203 and nuts 204. The lower cavity 21 is set on the top surface of the pressure plate 202. The four corners of the bottom plate 201 are also fixed with lower guide posts 2011 extending in the vertical direction, and the four corners of the pressure plate 202 are also fixed with lower guide holes 2021. The lower guide posts 2011 and the lower guide holes 2021 are inserted and matched one by one to ensure the precise docking between the bottom plate 201 and the pressure plate 202.

[0040] The lower cavity 21 is located on the top surface of the pressure plate 202, the negative pressure recess 27 is located on the bottom surface of the bottom plate 201, the bottom cover 28 is fixedly located at the opening of the negative pressure recess 27, a vacuum tube is fixedly connected to the bottom of the bottom cover 28, a branch pipe 281 is fixedly connected to the vacuum tube, a switch valve 282 is located on the branch pipe 281, a negative pressure gauge 271 is fixedly located at the bottom of the negative pressure recess 27, and the first through hole 22 includes a first lower through hole 221 located on the bottom plate 201 and connected to the negative pressure recess 27, and a coaxial line connecting the first lower through hole 221 and the lower cavity. The first upper through hole 222 between 21, the connecting channel 24 includes a lower connecting groove 241 respectively disposed on the top surface of the bottom plate 201 and an upper connecting groove 242 disposed on the bottom surface of the pressure plate 202, the groove opening of the lower connecting groove 241 coincides with the groove opening of the upper connecting groove 242, so that the lower connecting groove 241 and the upper connecting groove 242 combine to form the connecting channel 24; the second through hole 23 includes a second lower through hole 231 disposed on the bottom plate 201 and a second upper through hole 232 coaxially fixedly connected to the top of the second lower through hole 231 and connected to the flash groove 212.

[0041] The telescopic assembly 26 includes a telescopic cylinder 261, a movable frame 262, and a sliding rod 263. The cylinder of the telescopic cylinder 261 is fixed above the slide plate 61 and is upwardly oriented. The top end of the piston rod is fixedly connected to the bottom surface of the movable frame 262. The adjusting rod 25 is fixed above the movable frame 262. The sliding rod 263 is fixed below the bottom plate 201 and passes through the movable frame 262 in a vertical direction, so that the movable frame 262 and the sliding rod 263 slide in a sliding fit. This ensures that when the telescopic cylinder 261 is running, it can drive the sliding rod 263 to move in the vertical direction through the movable frame 262 under the guiding action of the sliding rod 263.

[0042] A further improvement is that the upper mold 3 is connected to a pressure control component 32, which is used to automatically limit the rubber pressure in the molding cavity during injection molding.

[0043] With the above design, the pressure control component 32 limits the rubber pressure in the molding cavity during injection, preventing excessive rubber pressure from causing mold deformation and damage, which would affect the subsequent injection accuracy.

[0044] A further improvement is that the bottom and top surfaces of the upper mold 3 are respectively provided with an axially vertical and interconnected third through hole 33 and a receiving recess 34. The cross-sectional dimension of the receiving recess 34 is larger than that of the third through hole 33. The pressure control component 32 includes a pressure control rod 321 that slides vertically in the third through hole 33 and a counterweight block 322 fixed to the top of the pressure control rod 321 and located in the receiving recess 34. The movable range of the pressure control component 32 is the forming station. In the forming station, the bottom surface of the counterweight block 322 and the bottom surface of the pressure control rod 321 are respectively in contact with the bottom wall of the receiving recess 34 and the bottom surface of the receiving recess 34.

[0045] With the above design, the pressure inside the molding cavity can be automatically limited during injection molding. Specifically, when the adjusting rod 25 moves upward, it squeezes the rubber inside the molding cavity, increasing the density of the rubber and increasing the pressure of the rubber inside the molding cavity. When the pressure increases to a level greater than the weight of the pressure control component 32, the molten rubber, under the extrusion state, pushes the pressure control component 32 upward, causing the pressure control rod 321 to drive the counterweight 322 to move upward in the vertical direction. This frees up some space at the bottom of the third through hole 33 to accommodate excess rubber, preventing excessive rubber pressure inside the limited space of the molding cavity. Generally, the greater the rubber pressure, the greater the upward movement of the pressure control rod 321, and the larger the space freed up in the third through hole 33 to accommodate excess rubber and prevent excessive pressure inside the molding cavity.

[0046] A further improvement is that the upper mold 3 can be detachably fixed to the output end of the lifting assembly 4, making it convenient to disassemble, replace and maintain the upper mold 3.

[0047] The specific structure of lifting component 4 is as follows: Figures 3-5As shown, the system includes a fixed frame 41, a lifting cylinder 42, and a lifting frame 43. Three fixed frames 41 and three lifting cylinders 42 are evenly spaced along the length of the base 11, each corresponding to the other. The fixed frame 41 is inverted U-shaped, with both ends fixed to the top of the base 11. The cylinder of the lifting cylinder 42 is fixed to the top of the fixed frame 41 and faces downwards. The bottom end of the piston rod is fixedly connected to the lifting frame 43. The lifting frame 43 includes a horizontal lifting frame 431. Several connecting rods 432 extending vertically are spaced along the circumference of the lifting frame 431 above it. A horizontal bar 433 is fixed to the top of the connecting rod 432. Three horizontal bars 433 are spaced apart along the length of the base 11, and guide rods 434 extending vertically upward are fixed at both ends. A guide hole is provided at the top of the fixing frame 41. The outer circumferential edge of the guide rod 434 is sealed and fitted with the inner circumferential wall of the guide hole. The upper mold 3 is detachably set below the lifting frame 431. Thus, after the lifting cylinder 42 is running, the sliding cooperation between the fixing frame 41 and the guide rod 434 causes the lifting frame 43 to drive the upper mold 3 to move smoothly in the vertical direction.

[0048] More specifically, such as Figure 7 , Figure 8 , Figures 10-12 As shown, the upper mold 3 includes a top plate 301 and a pressure plate 302 that are horizontally arranged from top to bottom. The top plate 301 and the pressure plate 302 are fixed to the lower part of the lifting frame 431 by upper bolts 303 and upper nuts 304 connected by threads at the four corners. In order to ensure the assembly accuracy of the top plate 301 and the pressure plate 302, the bottom surface of the top plate 301 is fixed with downward upper guide tubes 3013 at the four corners, and the pressure plate 302 is fixed with upper guide holes 3024 at the four corners. The outer circumferential edge of the upper guide tube 3013 is sealed and fitted with the inner circumferential wall of the upper guide hole 3024. Furthermore, when the upper mold 3 and the lower mold 2 are closed, the lower guide post 2011 is inserted and fitted with the upper guide hole 3024 to improve the closing accuracy of the lower mold 2 and the upper mold 3.

[0049] The glue injection channel 31 includes an upper glue injection through hole 3011, a glue injection blind hole 3021, an upper glue injection groove 3012, a lower glue injection groove 3022, and a lower glue injection through hole 3023. The upper glue injection through hole 3011 and the blind hole 3021 are connected along the same axis. The upper glue injection through hole 3011 is located on the top plate 301 and extends vertically. The blind hole 3021 is located on the top surface of the pressure plate 302. The upper glue injection groove 3012 is located on the bottom surface of the top plate 301 and connects with the bottom end of the upper glue injection through hole 3011. The lower glue injection groove 3022 is located on the top surface of the pressure plate 302 and connects with the blind hole 3021. The groove openings of the upper glue injection groove 3012 and the lower glue injection groove 3022 overlap and combine to form a glue injection flow channel. The lower glue injection through hole 3023 extends vertically and connects with the lower glue injection groove 3022. With the above structure, the molten rubber output from the injection molding machine flows downward from the injection upper through hole 3011 into the injection blind hole 3021, then enters horizontally between the injection upper groove 3012 and the injection lower groove 3022, flows downward through the injection lower through hole 3023, and enters the molding cavity to connect with the metal insert 5, solidifying to form the product. Moreover, with the above structure, it is convenient to separate the top plate 301 and the pressure plate 302 of the upper mold 3 to clean the residual rubber in the injection channel 31. After cleaning, the two are connected to the bottom of the lifting frame 431 for convenient subsequent injection molding production.

[0050] The receiving recess 34 is an annular blind hole formed on the top surface of the top plate 301. The third through hole 33 includes a third upper through hole 332 connected to the bottom of the receiving recess 34 and disposed on the top plate 301, and a third lower through hole 331 disposed on the pressure plate 302 and coaxially connected to the third upper through hole 332. The inner diameter of the third lower through hole 331 is the same as that of the third upper through hole 332, and they are distributed in a ring array below the receiving recess 34. With the above structure, it is convenient to limit the position of the pressure control member 32. In the pressure control member 32, the circumferential outer edge of the pressure control rod 321 is sealed and fitted with the circumferential inner wall of the third through hole 33. The counterweight 322 is integrally formed on the top of the pressure control rod 321. The counterweight 322 is cylindrical and protrudes from the top surface of the upper mold 3, ensuring that the counterweight 322 has sufficient weight and avoiding the counterweight 322 being too light, which would result in the pressure limited by the pressure control member 32 being too small and affecting the density of the rubber in the molding cavity.

[0051] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. An injection mold for a flow precision control sealing valve plate, comprising a mold base, a lower mold, an upper mold, and a lifting assembly, wherein the lower mold is disposed on the mold base and has a lower cavity and a first through hole that are coaxially connected from top to bottom and have a vertical axis; the lower cavity is used to place the cap portion of a metal insert, and the first through hole is used to receive and radially position the rod portion of the metal insert; the upper mold is disposed on the mold base via the lifting assembly and moves between a mold closing station and a mold parting station; the upper mold at the mold closing station is used to combine with the lower mold to form a molding mold; the molding mold has a built-in molding cavity and is provided with a glue injection channel communicating with the molding cavity; a material removal gap is provided between the upper mold and the lower mold at the mold parting station, characterized in that: The molding cavity includes a product cavity and a flash cavity that are connected. The lower mold is also provided with a second through hole with a vertical axis and the top of the flash cavity is connected to the bottom of the flash cavity, and a connecting channel connecting the first through hole and the second through hole. One end of the connecting channel connected to the second through hole is a conductive end. An adjusting rod is provided in the second through hole and sealed to its circumferential inner wall. A telescopic component is also provided below the lower mold. The telescopic component drives the adjusting rod to move in the vertical direction to control the connection and disconnection between the conductive end and the flash cavity. The first through hole is used to connect a vacuum pump.

2. The injection mold for a flow precision control sealing valve plate according to claim 1, characterized in that: The adjustable rod's movable positions include a conducting position, a closing position, and a leveling position distributed sequentially from bottom to top. The top of the adjusting rod in the conducting position is located below the conducting end. The top of the adjusting rod in the closing position is located between the conducting end and the bottom wall of the flash cavity. The top of the adjusting rod in the leveling position is flush with the bottom wall of the flash cavity.

3. The injection mold for a flow precision control sealing valve plate according to claim 1, characterized in that: The bottom surface of the upper mold is a horizontal plane, and the molding cavity is formed by the cavity wall of the lower cavity and the bottom surface of the upper mold.

4. The injection mold for a flow precision control sealing valve plate according to claim 1, characterized in that: The flash cavity is adjacent to the product cavity and the top of the product cavity is connected to the flash cavity.

5. The injection mold for a flow precision control sealing valve plate according to claim 1, characterized in that: The upper mold is connected to a pressure control component, which is used to automatically limit the rubber pressure in the molding cavity during injection molding.

6. The injection mold for a flow precision control sealing valve plate according to claim 5, characterized in that: The bottom and top surfaces of the upper mold are respectively provided with an axially vertical and interconnected third through hole and a receiving recess. The cross-sectional dimension of the receiving recess is larger than the cross-sectional dimension of the third through hole. The pressure control component includes a pressure control rod that slides vertically in the third through hole and a counterweight block fixed to the top of the pressure control rod and located in the receiving recess.

7. The injection mold for a flow precision control sealing valve plate according to claim 6, characterized in that: The movable range of the pressure control component is the forming station. At the forming station, the bottom surface of the counterweight and the bottom surface of the pressure control rod are respectively in contact with the bottom wall of the recess and the bottom surface of the recess.

8. The injection mold for a flow precision control sealing valve plate according to any one of claims 1-7, characterized in that: The molding cavity is provided in multiple and arranged in close succession. The flash cavities of adjacent molding cavities are interconnected. The bottom surface of the lower mold is provided with a negative pressure depression. The first through hole corresponding to each molding cavity is connected to the negative pressure depression. The negative pressure depression is fixedly covered with a bottom cover. A vacuum tube for connecting a vacuum pump is opened on the bottom cover. The negative pressure depression and the bottom cover enclose a negative pressure cavity. A negative pressure gauge is provided in the negative pressure cavity.

9. The injection mold for a flow precision control sealing valve plate according to claim 8, characterized in that: The bottom cover is also connected to a branch pipe that communicates with the outside. A switch valve is installed on the branch pipe. The movable position of the adjusting rod also includes a lifting position located above the leveling position, so as to lift the air edge by adjusting the rod.

10. The injection mold for a flow precision control sealing valve plate according to any one of claims 1-7, characterized in that: The bottom surface of the metal insert cap is sealed and fitted to the bottom cavity wall of the lower cavity, and the circumferential outer edge of the metal insert rod is sealed and fitted to the circumferential inner wall of the first through hole.

Images