Flexible ejection device for injection molding machine and use method of flexible ejection device

Abstract

The invention discloses a flexible ejection device for an injection molding machine, and relates to the technical field of plastic processing equipment, and the flexible ejection device comprises an outer frame assembly, a first buffer assembly, a second buffer assembly, a reset assembly and a limiting assembly. In the initial demolding stage of a plastic finished product, due to the fact that friction force is large, ejector pins at different positions can bear different counter-acting force, under the thrust of a hydraulic cylinder and the demolding counter-acting force, the ejector pins apply pressure to a second circular sleeve through a sealing top plate connected with a second plane bearing, the ejector pins contract towards the interior of a first circular sleeve and rotate, and it is ensured that the moving speed is stable; as the second circular sleeve goes deep into the first circular sleeve, internal air is gradually compressed, rigid pushing of the hydraulic cylinder is converted into flexible pushing, the plastic finished product is completely pushed out, the ejector pin applies different pushing forces according to different areas of the plastic finished product through the design, the ejection action is flexible, and deformation or breakage of the finished product is avoided; and high requirements of high-quality plastic products on the ejection process are met.

Description

Technical Field

[0001] The invention relates to the technical field of plastic processing equipment, in particular to a flexible ejector device for an injection molding machine and a use method thereof. Background Art

[0002] The ejector device is a device in the opening and closing part of the injection molding machine that links with the mold to realize the ejection and falling function of the plastic product. Each cycle of injection molding by the injection molding machine includes four steps: mold closing, injection, cooling, and mold opening. After the injection molding machine opens the mold, the injection molded product must be taken out of the mold cavity. At present, the ejector device used in the injection molding machine mainly uses hydraulic or pneumatic pressure as the driving power to directly push multiple ejectors to eject the plastic product.

[0003] Traditional ejector devices usually adopt a rigid structure, and use driving power to directly and synchronously push multiple ejector pins to push out plastic products. However, after the plastic product is cooled and formed in the cavity, it will be tightly combined with the cavity wall, generating considerable friction. In this case, if the ejector pins show too high rigidity in the initial stage of demolding, it will cause excessive ejection force, thereby causing damage to the plastic product. This problem is particularly prominent in thin-walled and fine-structured plastic products, and is prone to cause undesirable phenomena such as ejection breakage and ejection deformation. Therefore, the overall action of the traditional ejector device is relatively rigid and lacks the necessary flexibility, making it difficult to meet the high requirements of high-quality plastic products for the ejection process.

[0004] Therefore, a flexible ejector device for an injection molding machine and a method of using the same are proposed to solve the above-mentioned problems. Summary of the invention

[0005] The purpose of the present invention is to provide a flexible ejector device for an injection molding machine and a method of using the same, so as to solve the problem that the overall movement of the traditional ejector device proposed in the above background technology is relatively stiff, lacks the necessary flexibility, and is difficult to meet the high requirements of the ejection process for high-quality plastic products.

[0006] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a flexible ejection device for an injection molding machine, comprising an outer frame component, a first buffer component, a second buffer component, a reset component and a limit component, wherein the first buffer component, the second buffer component, the reset component and the limit component are all arranged inside the outer frame component, a second plane bearing is installed on the top of the second buffer component, an ejector pin is fixedly installed on the top of the second plane bearing, the outer frame component comprises an outer shell, a push plate is slidably arranged inside the outer shell, the first buffer component is set to a plurality of components for flexibly pushing the ejector pin, an air storage pipe is included, and the second buffer component is arranged on the top of the second plane bearing. Installed on the right side of the first buffer component, used for flexibly pushing the ejector pin, including a first circular sleeve and a second circular sleeve, the bottom of the first circular sleeve is fixedly installed with a sealing bottom plate, the top of the second circular sleeve is provided with a sealing top plate, the inner surface wall of the first circular sleeve is provided with an internal thread, the outer surface of the second circular sleeve is provided with an external thread, the first circular sleeve and the second circular sleeve are threadedly connected with the external thread through the internal thread, the reset component is installed between the second buffer component and the outer surface of the first buffer component, used for pushing the first buffer component to reset, including a first connecting rod and a second connecting rod, the limit assembly is installed inside the second buffer component, and includes a connecting rope.

[0007] Preferably, a hydraulic cylinder is installed on the left surface of the shell, and the telescopic end of the hydraulic cylinder passes through the shell and is fixedly connected to the push plate. A fixed plate is installed on the right surface of the shell, and a plurality of ejection holes are opened on the outer surface of the fixed plate. The outer surface of the ejector pin and the inner surface wall of the ejection hole are slidably fitted.

[0008] Preferably, the plurality of gas storage tubes are fixedly mounted on the right surface of the push plate, a sealing plate is fixedly mounted on the right end of the gas storage tube, nitrogen is injected into the interior of the gas storage tube, a gas injection nozzle is embedded on the outer surface of the gas storage tube near the left side, and a piston is installed between the inner surface walls of the gas storage tube near the right side.

[0009] Preferably, a push rod is fixedly connected to the right surface of the piston, the right end of the push rod passes through the sealing plate and extends to the right, the right end of the push rod is fixedly connected to the left end of the sealing bottom plate, and the right surface of the sealing top plate is connected to the left surface of the second plane bearing.

[0010] Preferably, a first connecting hole is symmetrically opened on the outer surface of the first circular sleeve near the right end, and a second connecting hole is symmetrically opened on the outer surface of the second circular sleeve near the left end. When the second circular sleeve is in an initial position, the positions of the first connecting hole and the second connecting hole coincide, and the outer diameter of the first circular sleeve is consistent with the outer diameter of the air storage pipe.

[0011] Preferably, a first plane bearing is installed at the left end of the second circular sleeve, a spring is fixedly connected to the left surface of the first plane bearing, the left end of the spring is in conflict with the right surface of the sealing bottom plate and the middle part of the spring is in a contracted state.

[0012] Preferably, the right end of the connecting rope is fixedly connected to a first bolt nut, the left end of the connecting rope is fixedly connected to a second bolt nut, the first bolt nut is threadedly connected to the center of the left surface of the sealing top plate, the second bolt nut is threadedly connected to the center of the right surface of the sealing bottom plate, and the connecting rope is located on the inner side of the spring.

[0013] Preferably, the right end of the first connecting rod and the left end of the second connecting rod are rotatably connected via a rotating pin, the left end of the first connecting rod is rotatably connected to a first rotating seat via a rotating pin, and the right end of the second connecting rod is rotatably connected to a second rotating seat via a rotating pin, the first rotating seat is fixedly connected to the outer surface of the gas storage pipe, the second rotating seat is fixedly connected to the outer surface of the first circular sleeve, and the positions of the first rotating seat and the second rotating seat correspond to each other.

[0014] Preferably, a first outer groove is formed on the outer surface of the first connecting rod, a second outer groove is formed on the outer surface of the second connecting rod, a first elastic ring is arranged between the inner wall of the first outer groove and the outer surface of the gas storage tube, and a second elastic ring is arranged between the inner wall of the second outer groove and the outer surface of the first circular sleeve.

[0015] A method for using a flexible ejector device for an injection molding machine comprises the following steps: S1. When the injection molding machine completes the injection molding and the plastic product needs to be ejected after being cooled and formed inside the mold cavity, the hydraulic cylinder is started to push the push plate inside the shell toward the mold. At this time, under the push of the push plate, multiple ejectors will pass through the ejection holes on the surface of the fixed plate and push different positions of the plastic product outward; S2. Ejectors at different positions will be subject to reaction forces of different strengths. Under the continuous thrust generated by the hydraulic cylinder and the reaction force generated during the demoulding process of the finished plastic product, the sealing top plate connected by the ejector through the second plane bearing will apply pressure to the second circular sleeve, and the second circular sleeve will shrink into the first circular sleeve. S3. Under the action of the external thread and the internal thread, the second circular sleeve will be in a state of self-rotation during the movement inside the first circular sleeve, so the moving speed of the second circular sleeve is stable. As the second circular sleeve goes deeper into the first circular sleeve, the air inside the second circular sleeve and the first circular sleeve will be gradually compressed until it reaches an incompressible state. In this process, the rigid push of the hydraulic cylinder on the ejector pin will be converted into flexible push, thereby pushing the finished plastic product out of the cavity intactly; S4. When the gas inside the first circular sleeve and the second circular sleeve is compressed to a certain extent, the second circular sleeve will push the piston inside the gas storage tube through the push rod to start compressing the nitrogen inside the gas storage tube, and the extra stroke obtained by compressing the nitrogen will assist the movement of the ejector pin.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. During use, at the initial stage of demoulding of the finished plastic product, due to the large friction, the ejectors at different positions will be subjected to different reaction forces. Under the thrust of the hydraulic cylinder and the reaction force of demoulding, the ejector applies pressure to the second circular sleeve through the sealing top plate connected to the second plane bearing, causing it to shrink and rotate inside the first circular sleeve, ensuring a stable activity speed. As the second circular sleeve penetrates deeper into the first circular sleeve, the internal air is gradually compressed, and the rigid push of the hydraulic cylinder is converted into a flexible push, pushing out the finished plastic product intact. This design enables the ejector to apply different thrusts according to different areas of the finished plastic product, making the ejection action flexible, avoiding deformation or cracking of the finished product, and meeting the high requirements of the ejection process for high-quality plastic products; 2. During use, since nitrogen is stored in the gas storage tube, it is more difficult to compress nitrogen than air. When the gas inside the first circular sleeve and the second circular sleeve is compressed to a certain extent, the second circular sleeve pushes the piston in the gas storage tube through the push rod to start compressing the nitrogen. This process provides an extra stroke for plastic products that are difficult to demold, avoiding product damage caused by forced ejection of the ejector pin. Therefore, this design can meet the high requirements of higher quality plastic products for the ejection process and ensure that the finished plastic products are not damaged during the demolding process; 3. When in use, when the ejector ejects the plastic product, the second circular sleeve contracts by squeezing the spring through the first plane bearing. After the ejection action is completed, the hydraulic cylinder drives the ejector to reset, and the spring rebounds. At the same time, the compressed air inside the first circular sleeve and the second circular sleeve releases the stored elastic potential energy, pushing the second circular sleeve to reset. When the second circular sleeve retreats to the initial position, the first connecting hole and the second connecting hole overlap, so that the air inside and outside is connected to replenish the energy lost by compression. At this time, the connecting rope is straightened to limit the maximum stroke of the second circular sleeve. The overall structure is simple and reasonable, ensuring the long-term stable and reliable use of the device; 4. During use, when the piston compresses the nitrogen in the gas storage tube, the first circular sleeve will approach the gas storage tube, and the first rotating seat and the second rotating seat will also approach each other, causing the first connecting rod and the second connecting rod to rotate outward, stretching the first elastic ring and the second elastic ring. As the ejector pin is reset, the nitrogen pressure in the gas storage tube is released, pushing the piston back. At this time, the elastic force of the first elastic ring and the second elastic ring causes the first connecting rod and the second connecting rod to return to their initial positions, ensuring that the piston and the first circular sleeve are completely reset. This design ensures the smooth progress of subsequent flexible ejection operations and improves the reliability and stability of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A three-dimensional diagram of a flexible ejector device for an injection molding machine according to the present invention; Figure 2 A cross-sectional view of a flexible ejector device for an injection molding machine according to the present invention; Figure 3 This is a schematic structural diagram of an outer frame assembly of a flexible ejection device for an injection molding machine according to the present invention; Figure 4 This is a schematic structural diagram of a first buffer component of a flexible ejector device for an injection molding machine according to the present invention; Figure 5 It is a partial structural schematic diagram of a flexible ejector device for an injection molding machine of the present invention; Figure 6 This is a schematic diagram of an ejector structure of a flexible ejector device for an injection molding machine according to the present invention; Figure 7 It is a cross-sectional expansion diagram of a second buffer component of a flexible ejection device for an injection molding machine according to the present invention; Figure 8 This is a schematic structural diagram of a reset component of a flexible ejector device for an injection molding machine according to the present invention; Fig. 9 The present invention is a schematic diagram of the structure of a limit assembly of a flexible ejection device for an injection molding machine.

[0018] In the figure: 1. Frame assembly; 101. Shell; 102. Hydraulic cylinder; 103. Push plate; 104. Fixed plate; 105. Ejection hole; 2. First buffer assembly; 201. Gas storage pipe; 202. Sealing plate; 203. Piston; 204. Push rod; 205. Gas injection nozzle; 3. Second buffer assembly; 301. First circular sleeve; 302. Sealing bottom plate; 303. Sealing top plate; 304. Second circular sleeve; 305. External thread; 306. Internal thread; 307. First plane axis Bearing; 308, spring; 309, first connecting hole; 310, second connecting hole; 4, second plane bearing; 41, ejector pin; 5, reset assembly; 501, first connecting rod; 502, second connecting rod; 503, first rotating seat; 504, second rotating seat; 505, first outer groove; 506, second outer groove; 507, first elastic ring; 508, second elastic ring; 6, limit assembly; 601, first bolt cap; 602, second bolt cap; 603, connecting rope. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the implementation regulations described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] Embodiment 1, refer to Figure 1-Figure 9As shown: a flexible ejection device for an injection molding machine, comprising an outer frame component 1, a first buffer component 2, a second buffer component 3, a reset component 5 and a limit component 6, the first buffer component 2, the second buffer component 3, the reset component 5 and the limit component 6 are all arranged inside the outer frame component 1, a second plane bearing 4 is installed on the top of the second buffer component 3, and an ejector pin 41 is fixedly installed on the top of the second plane bearing 4, the outer frame component 1 comprises a shell 101, a push plate 103 is slidably arranged inside the shell 101, the first buffer component 2 is set to a plurality of numbers for flexibly pushing the ejector pin 41, and comprises an air storage pipe 201, the second buffer component 3 is installed on the right side of the first buffer component 2, and is used for flexibly pushing the ejector pin 41. The push pin 41 includes a first circular sleeve 301 and a second circular sleeve 304. A sealing bottom plate 302 is fixedly installed at the bottom of the first circular sleeve 301, and a sealing top plate 303 is arranged on the top of the second circular sleeve 304. An inner surface wall of the first circular sleeve 301 is provided with an internal thread 306, and an outer surface of the second circular sleeve 304 is provided with an external thread 305. The first circular sleeve 301 and the second circular sleeve 304 are threadedly connected with the external thread 305 through the internal thread 306. The reset component 5 is installed between the outer surfaces of the second buffer component 3 and the first buffer component 2, and is used to push the first buffer component 2 to reset. It includes a first connecting rod 501 and a second connecting rod 502. The limit component 6 is installed on the second buffer component 3 The interior of the housing 101 includes a connecting rope 603, a hydraulic cylinder 102 is installed on the left surface of the housing 101, and the telescopic end of the hydraulic cylinder 102 passes through the housing 101 and is fixedly connected to the push plate 103, a fixed plate 104 is installed on the right surface of the housing 101, and a plurality of ejection holes 105 are provided on the outer surface of the fixed plate 104, and the outer surface of the ejector pin 41 and the inner surface wall of the ejection hole 105 are slidably fitted, a plurality of gas storage pipes 201 are fixedly installed on the right surface of the push plate 103, a sealing plate 202 is fixedly installed on the right end of the gas storage pipe 201, nitrogen is injected into the gas storage pipe 201, a gas injection nozzle 205 is embedded in the outer surface of the gas storage pipe 201 near the left side, and a gas injection nozzle 205 is embedded in the inner surface wall of the gas storage pipe 201 near the right side. A piston 203 is installed, and a push rod 204 is fixedly connected to the right surface of the piston 203. The right end of the push rod 204 penetrates the sealing plate 202 and extends to the right. The right end of the push rod 204 is fixedly connected to the left end of the sealing bottom plate 302. The right surface of the sealing top plate 303 is connected to the left surface of the second plane bearing 4. The outer surface of the first circular sleeve 301 is symmetrically provided with first connecting holes 309 near the right end, and the outer surface of the second circular sleeve 304 is symmetrically provided with second connecting holes 310 near the left end. When the second circular sleeve 304 is in the initial position, the positions of the first connecting holes 309 and the second connecting holes 310 coincide with each other, and the outer diameter of the first circular sleeve 301 is consistent with the outer diameter of the gas storage pipe 201.

[0021] In this embodiment, the push plate 103 is mainly driven by the hydraulic cylinder 102, thereby driving the first buffer assembly 2, the second buffer assembly 3 and the ejector pin 41 to move outward to perform the plastic product ejection operation. The gas injection nozzle 205 is mainly used to replenish the nitrogen lost in the gas storage tube 201 due to multiple compressions. The ejector pin 41 and the sealing ejector plate 303 are connected by the second plane bearing 4. Therefore, during the rotation of the second circular sleeve 304, the ejector pin 41 can stably push the plastic product outward. The middle part of the spring 308 is in a contracted shape. Therefore, even if it is twisted after being compressed, it will not be stuck in the internal thread 306. The spring 308 and the second circular sleeve 304 are connected by the first plane bearing 307. Therefore, the spring 308 will not be affected by the rotating second circular sleeve after being compressed. The impact of the round sleeve 304, when the injection molding machine is completed and the plastic product needs to be ejected after cooling and molding inside the mold cavity, the hydraulic cylinder 102 is started to push the push plate 103 inside the shell 101 to move toward the mold. At this time, under the push of the push plate 103, multiple ejector pins 41 will pass through the ejection holes 105 on the surface of the fixed plate 104 and push different positions of the plastic product outward. Due to the excessive friction in the initial stage of demolding of the plastic product, the ejector pins 41 at different positions will be subjected to reaction forces of different strengths. Under the thrust continuously generated by the hydraulic cylinder 102 and the reaction force generated during the demolding process of the plastic product, the ejector pins 41 will apply pressure to the second circular sleeve 304 through the sealing ejector plate 303 connected to the second plane bearing 4. At this time, the second circular sleeve 304 The second circular sleeve 304 will shrink into the first circular sleeve 301, and under the action of the external thread 305 and the internal thread 306, the second circular sleeve 304 will be in a state of self-rotation during the movement inside the first circular sleeve 301, so the movement speed is stable. As the second circular sleeve 304 goes deeper into the first circular sleeve 301, the air inside the second circular sleeve 304 and the first circular sleeve 301 will be gradually compressed until it reaches an incompressible state. During this process, the rigid push of the hydraulic cylinder 102 on the ejector pin 41 will be converted into a flexible push, thereby pushing the finished plastic product out of the cavity intact and completing the demoulding operation. This design allows the ejector pins 41 at different positions to apply different thrusts according to different areas of the finished plastic product, and the ejection action is more flexible. , so that the finished plastic product is not easily deformed or even broken by the ejection, which can meet the high requirements of the ejection process for higher-quality plastic products. In addition, since the gas stored in the gas storage tube 201 is nitrogen, nitrogen is difficult to be compressed compared to air. Therefore, when the gas inside the first circular sleeve 301 and the second circular sleeve 304 is compressed to a certain extent, the second circular sleeve 304 will push the piston 203 inside the gas storage tube 201 through the push rod 204 to start compressing the nitrogen inside the gas storage tube 201. Therefore, for plastic products that are difficult to demold, the extra stroke obtained by compressing nitrogen further avoids the problem of product damage caused by the ejector pin 41 forcibly ejecting the finished plastic product, which can meet the high requirements of the ejection process for higher-quality plastic products.

[0022] Embodiment 2, as Figure 6 , Figure 7 and Fig. 9 As shown, the left end of the second circular sleeve 304 is installed with the first plane bearing 307, the left surface of the first plane bearing 307 is fixedly connected with the spring 308, the left end of the spring 308 is in conflict with the right surface of the sealing bottom plate 302 and the middle part of the spring 308 is in a contracted state, the right end of the connecting rope 603 is fixedly connected with the first bolt cap 601, the left end of the connecting rope 603 is fixedly connected with the second bolt cap 602, the first bolt cap 601 is threadedly connected to the center of the left surface of the sealing top plate 303, the second bolt cap 602 is threadedly connected to the center of the right surface of the sealing bottom plate 302, and the connecting rope 603 is located at the inner side of the spring 308.

[0023] In this embodiment, when the ejector pin 41 ejects the plastic product, the second circular sleeve 304 moves toward the inside of the first circular sleeve 301 and squeezes the spring 308 through the first plane bearing 307 to contract. When the ejection action is completed, the hydraulic cylinder 102 drives the ejector pin 41 to return to the initial position. The spring 308 loses pressure and rebounds. The compressed air inside the first circular sleeve 301 and the second circular sleeve 304 loses pressure and releases the stored elastic potential energy synchronously, thereby pushing the second circular sleeve 304 to reset and wait for the next work. When 304 moves outward and approaches the initial position, the first connecting hole 309 and the second connecting hole 310 on the surface of the first circular sleeve 301 and the second circular sleeve 304 overlap, so that the inside and outside air are connected to replenish the energy lost by air compression. After the second circular sleeve 304 retreats to the initial position, the connecting rope 603 between the sealing top plate 303 and the sealing bottom plate 302 will be in a stretched state, which limits the maximum stroke of the second circular sleeve 304. The overall structure is simple and the design is reasonable, which can effectively ensure the stability of the device during long-term use.

[0024] Embodiment three, as Figure 2 , Figure 5 and Figure 8As shown, the right end of the first connecting rod 501 and the left end of the second connecting rod 502 are rotatably connected by a rotating pin, the left end of the first connecting rod 501 is rotatably connected to the first rotating seat 503 by the rotating pin, and the right end of the second connecting rod 502 is rotatably connected to the second rotating seat 504 by the rotating pin, the first rotating seat 503 is fixedly connected to the outer surface of the gas storage pipe 201, the second rotating seat 504 is fixedly connected to the outer surface of the first circular sleeve 301, and the positions of the first rotating seat 503 and the second rotating seat 504 correspond to each other, the outer surface of the first connecting rod 501 is provided with a first outer groove 505, the outer surface of the second connecting rod 502 is provided with a second outer groove 506, a first elastic ring 507 is arranged between the inner surface wall of the first outer groove 505 and the outer surface of the gas storage pipe 201, and a second elastic ring 508 is arranged between the inner surface wall of the second outer groove 506 and the outer surface of the first circular sleeve 301.

[0025] In the present embodiment, during use, when the piston 203 compresses the nitrogen inside the gas storage tube 201, the first circular sleeve 301 will approach the gas storage tube 201. At this time, the second rotating seat 504 and the first rotating seat 503 will approach each other synchronously, and prompt the first connecting rod 501 and the second connecting rod 502 to rotate outward, thereby stretching the first elastic ring 507 and the second elastic ring 508 sleeved inside the first outer groove 505 and the second outer groove 506. After the ejector pin 41 is reset, the nitrogen inside the gas storage tube 201 loses pressure and pushes the piston 203 back. At this time, the elastic force generated by the first elastic ring 507 and the second elastic ring 508 will re-tighten the first connecting rod 501 and the second connecting rod 502 to return to the initial position, thereby ensuring that the piston 203 and the first circular sleeve 301 are completely reset, ensuring the smooth implementation of the subsequent flexible ejection operation, and ensuring the reliability of the device when in use.

[0026] The use method and working principle of the device: When the injection molding machine completes the injection molding, and the plastic product needs to be ejected after being cooled and formed inside the mold cavity, the hydraulic cylinder 102 is started to push the push plate 103 inside the shell 101 to move toward the mold. At this time, under the push of the push plate 103, multiple ejector pins 41 will pass through the ejection holes 105 on the surface of the fixed plate 104 and push different positions of the finished plastic product outward. Due to the excessive friction in the initial stage of demolding the finished plastic product, the ejector pins 41 at different positions will be subjected to reaction forces of different strengths. Under the thrust continuously generated by the hydraulic cylinder 102 and the reaction force generated during the demolding process of the finished plastic product, the ejector pins 41 will apply pressure to the second circular sleeve 304 through the sealing ejector plate 303 connected to the second plane bearing 4. At this time, the second circular sleeve 304 The second circular sleeve 304 will shrink toward the inside of the first circular sleeve 301, and under the action of the external thread 305 and the internal thread 306, the second circular sleeve 304 will be in a state of self-rotation during the movement inside the first circular sleeve 301, so the movement speed is stable. As the second circular sleeve 304 goes deeper into the first circular sleeve 301, the air inside the second circular sleeve 304 and the first circular sleeve 301 will be gradually compressed until it reaches an incompressible state. In this process, the rigid push of the hydraulic cylinder 102 on the ejector pin 41 will be converted into a flexible push, thereby pushing the finished plastic product out of the mold cavity intact and completing the demoulding operation. This design allows the ejector pins 41 at different positions to apply different thrusts according to different areas of the finished plastic product, and the ejection action is more flexible, making the finished plastic product The product is not easily deformed or even broken by the ejection, which can meet the high requirements of the ejection process for higher-quality plastic products. In addition, since the gas stored in the gas storage tube 201 is nitrogen, which is difficult to compress compared to air, when the gas inside the first circular sleeve 301 and the second circular sleeve 304 is compressed to a certain extent, the second circular sleeve 304 will push the piston 203 inside the gas storage tube 201 through the push rod 204 to start compressing the nitrogen inside the gas storage tube 201. Therefore, for plastic products that are difficult to demold, the extra stroke obtained by compressing nitrogen further avoids the problem of product damage caused by the ejector pin 41 forcibly ejecting the plastic product, which can meet the high requirements of the ejection process for higher-quality plastic products. When the ejector pin 41 ejects the plastic product, the ejector pin 41 will be pushed out. During the ejection process, when the second circular sleeve 304 moves toward the inside of the first circular sleeve 301, it will squeeze the spring 308 through the first plane bearing 307 to shrink. When the ejection action is completed, the hydraulic cylinder 102 drives the ejector pin 41 to return to the initial position. The spring 308 loses pressure and rebounds. The compressed air inside the first circular sleeve 301 and the second circular sleeve 304 loses pressure and releases the stored elastic potential energy synchronously, thereby pushing the second circular sleeve 304 to reset and wait for the next work. When the second circular sleeve 304 moves outward and approaches the initial position, the first connecting hole 309 and the second connecting hole 310 on the surfaces of the first circular sleeve 301 and the second circular sleeve 304 overlap, so that the inside and outside air are connected, which plays a role in replenishing the energy lost by air compression.After the second circular sleeve 304 returns to the initial position, the connecting rope 603 between the sealing top plate 303 and the sealing bottom plate 302 will be in a straight state, which plays a role in limiting the maximum stroke of the second circular sleeve 304. The overall structure is simple and the design is reasonable, which can effectively ensure the stability of the device for long-term use. In addition, during use, when the piston 203 compresses the nitrogen inside the gas storage tube 201, the first circular sleeve 301 will approach the gas storage tube 201. At this time, the second rotating seat 504 and the first rotating seat 503 will move closer to each other synchronously, and promote the first connecting rod 501 and the second connecting rod 502 to move toward each other. The piston 203 is pushed back by the first elastic ring 507 and the second elastic ring 508 which are sleeved inside the first outer groove 505 and the second outer groove 506. The first elastic ring 507 and the second elastic ring 508 are rotated outward, thereby stretching the first elastic ring 507 and the second elastic ring 508 which are sleeved inside the first outer groove 505 and the second outer groove 506. After the ejector pin 41 is reset, the nitrogen inside the gas storage tube 201 loses pressure and pushes the piston 203 to retreat. At this time, the elastic force generated by the first elastic ring 507 and the second elastic ring 508 will tighten the first connecting rod 501 and the second connecting rod 502 back to the initial position, thereby ensuring that the piston 203 and the first circular sleeve 301 are completely reset, ensuring the smooth realization of the subsequent flexible ejection operation, and ensuring the reliability of the device when used.

[0027] The wiring diagram of the hydraulic cylinder 102 in the present invention is common knowledge in the art, and its working principle is a known technology. The model is selected according to the actual use, so the control method and wiring arrangement of the hydraulic cylinder 102 will not be explained in detail.

[0028] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A flexible ejector device for an injection molding machine, comprising an outer frame assembly (1), a first buffer assembly (2), a second buffer assembly (3), a reset assembly (5) and a limit assembly (6), characterized in that: The first buffer component (2), the second buffer component (3), the reset component (5) and the limit component (6) are all arranged inside the outer frame component (1); a second plane bearing (4) is installed on the top of the second buffer component (3); and a top pin (41) is fixedly installed on the top of the second plane bearing (4); The outer frame assembly (1) comprises an outer shell (101), and a push plate (103) is slidably arranged inside the outer shell (101); The first buffer components (2) are provided in a plurality and are used for flexibly pushing the ejector pin (41), and include an air outlet storage pipe (201); The second buffer assembly (3) is installed on the right side of the first buffer assembly (2) and is used to flexibly push the ejector pin (41). The second buffer assembly (3) comprises a first circular sleeve (301) and a second circular sleeve (304). A sealing bottom plate (302) is fixedly installed on the bottom of the first circular sleeve (301). A sealing top plate (303) is arranged on the top of the second circular sleeve (304). An inner surface wall of the first circular sleeve (301) is provided with an internal thread (306). An outer surface of the second circular sleeve (304) is provided with an external thread (305). The first circular sleeve (301) and the second circular sleeve (304) are threadedly connected to the external thread (305) via the internal thread (306). The reset assembly (5) is installed between the outer surfaces of the second buffer assembly (3) and the first buffer assembly (2) and is used to push the first buffer assembly (2) to reset, and comprises a first connecting rod (501) and a second connecting rod (502); The limiting component (6) is installed inside the second buffer component (3) and comprises a connecting rope (603).

2. A flexible ejector device for an injection molding machine according to claim 1, characterized in that: A hydraulic cylinder (102) is mounted on the left surface of the housing (101), and the telescopic end of the hydraulic cylinder (102) passes through the housing (101) and is fixedly connected to the push plate (103). A fixed plate (104) is mounted on the right surface of the housing (101), and a plurality of ejection holes (105) are formed on the outer surface of the fixed plate (104). The outer surface of the ejector pin (41) and the inner surface wall of the ejection hole (105) are slidably fitted.

3. A flexible ejector device for an injection molding machine according to claim 2, characterized in that: The plurality of gas storage pipes (201) are fixedly mounted on the right surface of the push plate (103); a sealing plate (202) is fixedly mounted on the right end of the gas storage pipe (201); nitrogen is injected into the interior of the gas storage pipe (201); a gas injection nozzle (205) is embedded in the outer surface of the gas storage pipe (201) near the left side; and a piston (203) is mounted between the inner surface walls of the gas storage pipe (201) near the right side.

4. A flexible ejector device for an injection molding machine according to claim 3, characterized in that: A push rod (204) is fixedly connected to the right surface of the piston (203); the right end of the push rod (204) passes through the sealing plate (202) and extends to the right; the right end of the push rod (204) is fixedly connected to the left end of the sealing bottom plate (302); and the right surface of the sealing top plate (303) is connected to the left surface of the second plane bearing (4).

5. A flexible ejector device for an injection molding machine according to claim 4, characterized in that: A first communication hole (309) is symmetrically formed on the outer surface of the first circular sleeve (301) near the right end, and a second communication hole (310) is symmetrically formed on the outer surface of the second circular sleeve (304) near the left end. When the second circular sleeve (304) is in the initial position, the first communication hole (309) and the second communication hole (310) are positioned in an overlapped position, and the outer diameter of the first circular sleeve (301) is consistent with the outer diameter of the gas storage pipe (201).

6. A flexible ejector device for an injection molding machine according to claim 5, characterized in that: A first plane bearing (307) is installed at the left end of the second circular sleeve (304), and a spring (308) is fixedly connected to the left surface of the first plane bearing (307). The left end of the spring (308) is in contact with the right surface of the sealing bottom plate (302), and the middle part of the spring (308) is in a contracted state.

7. A flexible ejector device for an injection molding machine according to claim 6, characterized in that: The right end of the connecting rope (603) is fixedly connected to a first bolt cap (601), and the left end of the connecting rope (603) is fixedly connected to a second bolt cap (602). The first bolt cap (601) is threadedly connected to the center of the left surface of the sealing top plate (303), and the second bolt cap (602) is threadedly connected to the center of the right surface of the sealing bottom plate (302). The connecting rope (603) is located at the inner side of the spring (308).

8. A flexible ejector device for an injection molding machine according to claim 7, characterized in that: The right end of the first connecting rod (501) and the left end of the second connecting rod (502) are rotatably connected via a rotating pin; the left end of the first connecting rod (501) is rotatably connected to a first rotating seat (503) via a rotating pin; the right end of the second connecting rod (502) is rotatably connected to a second rotating seat (504) via a rotating pin; the first rotating seat (503) is fixedly connected to an outer surface of the gas storage pipe (201); the second rotating seat (504) is fixedly connected to an outer surface of the first circular sleeve (301); and the first rotating seat (503) and the second rotating seat (504) are positioned correspondingly.

9. A flexible ejector device for an injection molding machine according to claim 8, characterized in that: The outer surface of the first connecting rod (501) is provided with a first outer groove (505), the outer surface of the second connecting rod (502) is provided with a second outer groove (506), a first elastic ring (507) is provided between the inner surface wall of the first outer groove (505) and the outer surface of the gas storage tube (201), and a second elastic ring (508) is provided between the inner surface wall of the second outer groove (506) and the outer surface of the first circular sleeve (301).

10. A method for using a flexible ejector device for an injection molding machine, characterized in that: The flexible ejector device for an injection molding machine according to claim 9 is used, comprising the following steps: S1. When the injection molding machine completes the injection molding and the plastic product needs to be ejected after being cooled and formed inside the mold cavity, the hydraulic cylinder (102) is started to push the push plate (103) inside the housing (101) toward the mold. At this time, under the push of the push plate (103), multiple ejector pins (41) pass through the ejection holes (105) on the surface of the fixed plate (104) and push different positions of the plastic product outward; S2. The ejector pins (41) at different positions are subjected to reaction forces of different strengths. Under the thrust force continuously generated by the hydraulic cylinder (102) and the reaction force generated during the demoulding process of the finished plastic product, the ejector pins (41) exert pressure on the second circular sleeve (304) through the sealing ejector plate (303) connected to the second plane bearing (4). At this time, the second circular sleeve (304) shrinks toward the inside of the first circular sleeve (301); S3. Under the action of the external thread (305) and the internal thread (306), the second circular sleeve (304) is in a state of self-rotation during the movement inside the first circular sleeve (301). Therefore, the moving speed of the second circular sleeve (304) is stable. As the second circular sleeve (304) penetrates deeper into the first circular sleeve (301), the air inside the second circular sleeve (304) and the first circular sleeve (301) is gradually compressed until it reaches an incompressible state. During this process, the rigid push of the hydraulic cylinder (102) on the ejector pin (41) is converted into a flexible push, thereby pushing the finished plastic product out of the mold cavity intact. S4. When the gases inside the first circular sleeve (301) and the second circular sleeve (304) are compressed to a certain extent, the second circular sleeve (304) will push the piston (203) inside the gas storage tube (201) through the push rod (204) to start compressing the nitrogen inside the gas storage tube (201), and the extra stroke obtained by compressing the nitrogen assists the movement of the ejector pin (41).

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