A flexible ejection device for an injection molding machine and method of use thereof

Abstract

The application discloses a flexible ejection device for an injection molding machine and relates to the technical field of plastic processing equipment. In the initial stage of demolding of the plastic finished product, different positions of the ejector pins are subjected to different reaction forces due to large friction, under the thrust of the hydraulic cylinder and the demolding reaction force, the sealing top plate connected with the second plane bearing of the ejector pin applies pressure to the second circular sleeve, so that the second circular sleeve is shrunk to the inside of the first circular sleeve and rotates by itself, the stability of the moving speed is ensured, with the second circular sleeve going deep into the first circular sleeve, the internal air is gradually compressed, the rigid pushing of the hydraulic cylinder is converted into flexible pushing, and the plastic finished product is perfectly pushed out, the design makes the ejector pins apply different thrust according to different regions of the plastic finished product, the ejection action is flexible, the deformation or breakage of the finished product is avoided, and the high requirements of high-quality plastic products on the ejection process are met.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of plastic processing equipment, in particular to a flexible ejection device for an injection molding machine and a use method thereof. BACKGROUND

[0002] The ejection device is a device for realizing the function of ejecting and falling of plastic products in the mold opening and closing part and mold linkage of the injection molding machine. Each cycle of injection molding of the injection molding machine includes four steps of mold closing, injection, cooling and mold opening. After the mold of the injection molding machine is opened, the injection molded product must be taken out from the mold cavity. At present, the ejection device for the injection molding machine mainly uses hydraulic or pneumatic driving power to directly push multiple ejector pins to eject the plastic product.

[0003] The traditional ejection device usually adopts a rigid structure and directly synchronously pushes multiple ejector pins to eject the plastic product through driving power. However, when the plastic product is cooled and formed in the cavity, it will be tightly combined with the cavity wall to generate a considerable friction force. In this case, if the ejector pin shows too high rigidity in the initial stage of demolding, it will cause too large ejection force, thereby causing damage to the plastic product. This problem is particularly prominent in thin-walled and fine-structured plastic products, which easily causes adverse phenomena such as top breaking and top deformation. Therefore, the overall action of the traditional ejection device is relatively rough, lacks necessary flexibility, and is difficult to meet the high requirements of high-quality plastic products on the ejection process.

[0004] Therefore, a flexible ejection device for an injection molding machine and a use method thereof are proposed to solve the problems in the background. SUMMARY

[0005] The present application aims to provide a flexible ejection device for an injection molding machine and a use method thereof to solve the problem of the traditional ejection device that the overall action is relatively rough, lacks necessary flexibility, and is difficult to meet the high requirements of high-quality plastic products on the ejection process.

[0006] In order to achieve the above object, the present application provides the following technical scheme: A flexible ejection device for an injection molding machine, comprising an outer frame assembly, a first buffer assembly, a second buffer assembly, a reset assembly and a limiting assembly, the first buffer assembly, the second buffer assembly, the reset assembly and the limiting assembly are arranged inside the outer frame assembly, a second plain bearing is installed on the top of the second buffer assembly, a thimble is fixedly installed on the top of the second plain bearing, the outer frame assembly comprises a shell, a push plate is slidably arranged inside the shell, the first buffer assembly is provided in plurality and is used for flexibly pushing the thimble, comprising a gas storage pipe, the second buffer assembly is installed on the right side of the first buffer assembly and is used for flexibly pushing the thimble, comprising a first circular sleeve and a second circular sleeve, a sealing bottom plate is fixedly installed on the bottom of the first circular sleeve, a sealing top plate is arranged on the top of the second circular sleeve, an inner thread is arranged on the inner surface wall of the first circular sleeve, an outer thread is arranged on the outer surface of the second circular sleeve, the first circular sleeve and the second circular sleeve are threadedly connected through the inner thread and the outer thread, the reset assembly is installed between the outer surfaces of the second buffer assembly and the first buffer assembly and is used for pushing the first buffer assembly to reset, comprising a first connecting rod and a second connecting rod, the limiting assembly is installed inside the second buffer assembly and comprises 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 penetrates the shell and is fixedly connected with the push plate, a fixed plate is installed on the right surface of the shell, a plurality of ejection holes are formed in the outer surface of the fixed plate, and the outer surface of the thimble and the inner surface wall of the ejection hole are in sliding fit.

[0008] Preferably, a plurality of the gas storage pipes are fixedly installed on the right surface of the push plate, a sealing plate is fixedly installed on the right end of the gas storage pipe, nitrogen is injected into the inside of the gas storage pipe, a gas injection nozzle is embedded on the position close to the left side of the outer surface of the gas storage pipe, and a piston is installed on the position close to the right side between the inner surface walls of the gas storage pipe.

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

[0010] Preferably, a first communication hole is symmetrically formed on the position close to the right end of the outer surface of the first circular sleeve, a second communication hole is symmetrically formed on the position close to the left end of the outer surface of the second circular sleeve, the first communication hole and the second communication hole are coincident in position when the second circular sleeve is in the initial position, and the outer diameter of the first circular sleeve is consistent with the outer diameter of the gas storage pipe.

[0011] Preferably, the left end of the second circular sleeve is provided with a first plane bearing, the left surface of the first plane bearing is fixedly connected with a spring, the left end of the spring abuts against 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 with a first bolt cap, the left end of the connecting rope is fixedly connected with a second bolt cap, the first bolt cap is threadedly connected at the center of the left surface of the sealing top plate, the second bolt cap is threadedly connected at the center of the right surface of the sealing bottom plate, and the connecting rope is located inside the spring.

[0013] Preferably, the right end of the first connecting rod and the left end of the second connecting rod are rotationally connected through a rotating pin, the left end of the first connecting rod is rotationally connected with a first rotating seat through a rotating pin, the right end of the second connecting rod is rotationally connected with a second rotating seat through 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 first rotating seat and the second rotating seat are located in corresponding positions.

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

[0015] A use method of a flexible ejection device for an injection molding machine, comprising the following steps:

[0016] S1, when the injection molding machine is completed, the plastic product is cooled and formed in the mold cavity, and needs to be ejected, the hydraulic cylinder is started to push the push plate inside the shell to move towards the mold, at this time, under the pushing of the push plate, a plurality of ejector pins will push the plastic product at different positions outside through the ejection holes in the fixed plate surface;

[0017] S2, the ejector pins at different positions will be subjected to different forces, under the continuous pushing force of the hydraulic cylinder and the reaction force generated during the demolding process of the plastic product, the sealing top plate connected through the second plane bearing will apply pressure to the second circular sleeve, at this time, the second circular sleeve will shrink towards the inside of the first circular sleeve;

[0018] S3, under the action of the external thread and the internal thread, the second circular sleeve will be in a state of rotation during the movement in the first circular sleeve, so that the movement speed of the second circular sleeve is stable, with the second circular sleeve deepening into the first circular sleeve, the air in the second circular sleeve and the first circular sleeve will be gradually compressed until it cannot be compressed, in this process, the rigid pushing of the hydraulic cylinder on the ejector pins will be converted into flexible pushing, and then the plastic product will be perfectly pushed out of the cavity;

[0019] 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 start to compress the nitrogen inside the gas storage pipe by pushing the piston inside the gas storage pipe through the push rod. The additional stroke obtained by compressing the nitrogen assists the movement of the ejector pin.

[0020] Compared with the prior art, the beneficial effects of the present application are:

[0021] 1. In use, at the initial stage of demolding the plastic product, the ejector pins at different positions will be subjected to different reaction forces due to large friction. Under the thrust of the hydraulic cylinder and the demolding reaction force, the ejector pins press the sealing top plate connected through the second plane bearing against the second circular sleeve, so that the second circular sleeve shrinks and rotates towards the inside of the first circular sleeve, ensuring stable movement speed. As the second circular sleeve penetrates into the first circular sleeve, the air inside is gradually compressed, and the rigid pushing of the hydraulic cylinder is converted into flexible pushing, and the plastic product is perfectly pushed out. This design allows the ejector pins to apply different thrusts according to different regions of the plastic product, making the ejection action flexible and avoiding deformation or rupture of the product, thus meeting the high requirements of high-quality plastic products on the ejection process.

[0022] 2. In use, since nitrogen is stored in the gas storage pipe, nitrogen is more difficult to compress 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 starts to compress the nitrogen by pushing the piston inside the gas storage pipe through the push rod. This process provides additional stroke for plastic products that are difficult to demold, avoiding damage to the product caused by forced ejection. Therefore, this design can meet the high requirements of higher quality plastic products on the ejection process, and ensure that the plastic product is not damaged during the demolding process.

[0023] 3. In use, during the process of ejecting the plastic product by the ejector pin, the second circular sleeve shrinks by pressing the spring through the first plane bearing. After the ejection action is completed, the hydraulic cylinder drives the ejector pin 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, driving the second circular sleeve to reset. When the second circular sleeve retreats to the initial position, the first communication hole and the second communication hole coincide, allowing the inside and outside air to communicate and supplement the energy loss. At this time, the connecting rope is taut, limiting the maximum stroke of the second circular sleeve. The overall structure is simple and reasonable, ensuring stable and reliable long-term use of the device.

[0024] 4. In use, when the piston compresses the nitrogen in the gas storage tube, the first circular sleeve will move towards the gas storage tube, and the first rotating seat and the second rotating seat will also move towards each other, causing the first connecting rod and the second connecting rod to rotate outward, lengthening the first elastic ring and the second elastic ring, and with the reset of the ejector pin, the nitrogen pressure in the gas storage tube is released, pushing the piston to retreat, at this time, the elastic force of the first elastic ring and the second elastic ring makes the first connecting rod and the second connecting rod return to the initial position, ensuring that the piston and the first circular sleeve are completely reset, which ensures the smooth progress of the subsequent flexible ejection operation and improves the reliability and stability of the device. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 FIG. 1 is a perspective view of a flexible ejection device for an injection molding machine according to the present application;

[0026] Figure 2 FIG. 2 is a sectional view of a flexible ejection device for an injection molding machine according to the present application;

[0027] Figure 3 FIG. 3 is a structural schematic diagram of an outer frame assembly of a flexible ejection device for an injection molding machine according to the present application;

[0028] Figure 4 FIG. 4 is a structural schematic diagram of a first buffer assembly of a flexible ejection device for an injection molding machine according to the present application;

[0029] Figure 5 FIG. 5 is a partial structural schematic diagram of a flexible ejection device for an injection molding machine according to the present application;

[0030] Figure 6 FIG. 6 is a structural schematic diagram of an ejector pin of a flexible ejection device for an injection molding machine according to the present application;

[0031] Figure 7 FIG. 7 is a sectional view of a second buffer assembly of a flexible ejection device for an injection molding machine according to the present application;

[0032] Figure 8 FIG. 8 is a structural schematic diagram of a reset assembly of a flexible ejection device for an injection molding machine according to the present application;

[0033] Figure 9 FIG. 9 is a structural schematic diagram of a limiting assembly of a flexible ejection device for an injection molding machine according to the present application.

[0034] In the drawings:

[0035] 1, outer frame assembly; 101, outer 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 bearing; 308, spring; 309, first communication hole; 310, second communication 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, limiting assembly; 601, first bolt cap; 602, second bolt cap; 603, connecting rope. DETAILED DESCRIPTION

[0036] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0037] Embodiment one, refer to Figures 1-9The utility model provides an injection molding machine flexible ejection device, including outer frame assembly 1, first buffer assembly 2, second buffer assembly 3, reset assembly 5 and limiting assembly 6, first buffer assembly 2, second buffer assembly 3, reset assembly 5 and limiting assembly 6 are all arranged in the inside of outer frame assembly 1, the top of second buffer assembly 3 is equipped with second plane bearing 4, the top of second plane bearing 4 is fixedly installed with ejector pin 41, outer frame assembly 1 includes shell 101, the inside of shell 101 is slidably provided with push plate 103, first buffer assembly 2 is set to multiple, is used for flexible push ejector pin 41, including gas storage pipe 201, second buffer assembly 3 is installed to the right side of first buffer assembly 2, is used for flexible push ejector pin 41, including first circular sleeve 301 and second circular sleeve 304, the bottom of first circular sleeve 301 is fixedly installed with sealing bottom plate 302, the top of second circular sleeve 304 is provided with sealing top plate 303, the inner wall of first circular sleeve 301 is equipped with internal thread 306, the outer surface of second circular sleeve 304 is equipped with external thread 305, first circular sleeve 301 and second circular sleeve 304 are connected through internal thread 306 and external thread 305, reset assembly 5 is installed between the outer surface of second buffer assembly 3 and first buffer assembly 2, is used for pushing first buffer assembly 2 reset, including first connecting rod 501 and second connecting rod 502, limiting assembly 6 is installed in the inside of second buffer assembly 3, including connecting rope 603, the left surface of shell 101 is installed with hydraulic cylinder 102, and the telescopic end of hydraulic cylinder 102 penetrates shell 101 and is fixedly connected with push plate 103, the right surface of shell 101 is installed with fixed plate 104, a plurality of ejection holes 105 are formed in the outer surface of fixed plate 104, the outer surface of ejector pin 41 and the inner wall of ejection hole 105 are slidably attached, a plurality of gas storage pipes 201 are fixedly installed on the right surface of push plate 103, the right end of gas storage pipe 201 is fixedly installed with sealing plate 202, nitrogen is injected into the inside of gas storage pipe 201, the position close to the left side of the outer surface of gas storage pipe 201 is embedded with gas injection nozzle 205, the position close to the right side between the inner wall of gas storage pipe 201 is installed with piston 203, the right surface of piston 203 is fixedly connected with push rod 204, the right end of push rod 204 penetrates sealing plate 202 and extends rightwards, the right end of push rod 204 and the left end of sealing bottom plate 302 are fixedly connected, the right surface of sealing top plate 303 is connected with the left surface of second plane bearing 4, the outer surface of first circular sleeve 301 is symmetrically provided with first communicating hole 309 near the right end, the outer surface of second circular sleeve 304 is symmetrically provided with second communicating hole 310 near the left end, when second circular sleeve 304 is located at the initial position, first communicating hole 309 and second communicating hole 310 are coincident in position, the outer diameter of first circular sleeve 301 is consistent with the outer diameter of gas storage pipe 201.

[0038] In this embodiment, the push plate 103 is mainly driven by the hydraulic cylinder 102 to provide a pushing force, thereby driving the first buffer assembly 2, the second buffer assembly 3 and the ejector pin 41 to move outwardly and then perform the plastic product ejection operation, the injection nozzle 205 is mainly used to supplement the nitrogen gas lost in the internal storage tube 201 due to multiple compressions, the ejector pin 41 and the sealing top plate 303 are connected through the second plane bearing 4, so that the ejector pin 41 can stably push the plastic product outwardly during the rotation of the second circular sleeve 304, the middle part of the spring 308 is in a contracted state, so that even if it is distorted after being compressed, it will not be stuck in the internal thread 306, the spring 308 and the second circular sleeve 304 are connected through the first plane bearing 307, so that the spring 308 will not be affected by the rotating second circular sleeve 304 after being compressed, when the injection molding machine completes the injection molding, and the plastic product needs to be ejected after being cooled and formed in the mold cavity, the hydraulic cylinder 102 is started to drive the push plate 103 in the outer shell 101 to move towards the mold, at this time, under the pushing of the push plate 103, the plurality of ejector pins 41 will push the plastic product at different positions outwardly through the ejection holes 105 on the surface of the fixed plate 104, due to the excessive friction force in the initial stage of the plastic product demolding, the ejector pins 41 at different positions will be subjected to different reaction forces, under the continuous pushing force of the hydraulic cylinder 102 and the reaction force generated during the demolding process of the plastic product, the sealing top plate 303 connected with the ejector pin 41 through the second plane bearing 4 will apply pressure to the second circular sleeve 304, at this time, 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 rotation during the movement in the first circular sleeve 301, so that the movement speed is stable, as the second circular sleeve 304 penetrates into the first circular sleeve 301, the air in the second circular sleeve 304 and the first circular sleeve 301 will be gradually compressed until it cannot be compressed, in this process, the rigid pushing of the hydraulic cylinder 102 to the ejector pin 41 will be converted into flexible pushing, thereby pushing the plastic product out of the cavity perfectly and completing the demolding operation, this design makes the ejector pins 41 at different positions apply different pushing forces according to the pressure of different regions of the plastic product, the ejection action is flexible, the plastic product is not easy to be deformed or even broken by the ejection, and can meet the high requirements of high-quality plastic products on the ejection process, and since the gas stored in the internal storage tube 201 is nitrogen, compared with air, nitrogen is difficult to compress, therefore, when the gas in the first circular sleeve 301 and the second circular sleeve 304 is compressed to a certain extent, the second circular sleeve 304 will start to compress the nitrogen gas in the internal storage tube 201 through the push rod 204 to drive the piston 203 in the internal storage tube 201, therefore, for the plastic products that are difficult to demold, the additional stroke obtained by compressing the nitrogen gas further avoids the problem that the ejector pin 41 forcibly ejects the plastic product and causes product damage, and can meet the high requirements of higher-quality plastic products on the ejection process.

[0039] Example two, as shown in Figure 6 , Figure 7 and Figure 9 , 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 abutment 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 at the center of the left surface of the sealing top plate 303, the second bolt cap 602 is threadedly connected at the center of the right surface of the sealing bottom plate 302, and the connecting rope 603 is located inside the spring 308.

[0040] In this embodiment, when the ejector pin 41 ejects the plastic product, the second circular sleeve 304 moves towards the inside of the first circular sleeve 301 and the spring 308 is compressed through the first plane bearing 307, when the ejector pin 41 returns to the initial position after the ejection action is completed, the spring 308 will rebound due to the loss of pressure, and the compressed air inside the first circular sleeve 301 and the second circular sleeve 304 will release the stored elastic potential energy synchronously after the loss of pressure, thereby pushing the second circular sleeve 304 to reset, waiting for the next work, and when the second circular sleeve 304 moves outward to approach the initial position, the first communication hole 309 and the second communication hole 310 on the surfaces of the first circular sleeve 301 and the second circular sleeve 304 coincide, thereby enabling the air inside and outside to communicate, supplementing the energy loss of air compression, and 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, thereby limiting the maximum stroke of the second circular sleeve 304, the overall structure is simple and reasonable, and the stability of the device during long-term use can be effectively ensured.

[0041] Example three, as shown in Figure 2 , Figure 5 and Figure 8 ,As 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 with a first rotating seat 503 through a rotating pin, the right end of the second connecting rod 502 is rotatably connected with a second rotating seat 504 through a rotating pin, the first rotating seat 503 is fixedly connected on the outer surface of the gas storage pipe 201, the second rotating seat 504 is fixedly connected on the outer surface of the first circular sleeve 301, and the first rotating seat 503 and the second rotating seat 504 are in position correspondence, 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, the inner surface wall of the first outer groove 505 and the outer surface of the gas storage pipe 201 are provided with a first elastic ring 507, and the inner surface wall of the second outer groove 506 and the outer surface of the first circular sleeve 301 are provided with a second elastic ring 508.

[0042] In this embodiment, during use, when the piston 203 compresses the nitrogen inside the gas storage pipe 201, the first circular sleeve 301 will be close to the gas storage pipe 201, at this time, the second rotating seat 504 and the first rotating seat 503 will synchronously approach, and will promote the first connecting rod 501 and the second connecting rod 502 to rotate outward, thereby making the first elastic ring 507 and the second elastic ring 508 sleeved inside the first outer groove 505 and the second outer groove 506 be elongated, and after the ejector pin 41 resets, the nitrogen inside the gas storage pipe 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 make the first connecting rod 501 and the second connecting rod 502 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 during use.

[0043] The working principle and method of using the device: when the injection molding machine is completed, the plastic product is cooled and formed in the mold cavity, and needs to be ejected, the hydraulic cylinder 102 is started to push the push plate 103 inside the shell 101 to move towards the mold direction, at this time, under the push of the push plate 103, a plurality of ejector pins 41 will be pushed outwards to different positions of the plastic product after passing through the ejection hole 105 on the surface of the fixed plate 104, due to the reason of excessive friction force in the initial stage of demolding of the plastic product, at this time, the ejector pins 41 in different positions will be subjected to different forces of the reaction force, under the continuous thrust of the hydraulic cylinder 102 and the reaction force generated in the demolding process of the plastic product, the sealing top plate 303 connected by the second plane bearing 4 will apply pressure to the second circular sleeve 304, at this time, the second circular sleeve 304 will shrink inside 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 rotation during the movement in the first circular sleeve 301, so the movement speed is stable, with the second circular sleeve 304 deepening 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 cannot be compressed, in this process, the rigid pushing of the hydraulic cylinder 102 to the ejector pin 41 will be converted into flexible pushing, and then the plastic product will be perfectly pushed out of the cavity, completing the demolding work, this design makes the ejector pins 41 in different positions apply different thrust forces according to the different pressure areas of the plastic product, the ejection action is more flexible, so that the plastic product is not easy to be deformed or even broken by ejection, which can meet the high requirements of high-quality plastic products for the ejection process, and because the gas stored in the gas storage pipe 201 is nitrogen, compared with air, nitrogen is difficult to compress, 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 start to compress the nitrogen inside the gas storage pipe 201 by pushing the piston 203 inside the gas storage pipe 201 through the push rod 204, therefore, for the plastic products that are difficult to demold, the additional stroke obtained by compressing nitrogen further avoids the problem of product damage caused by forcibly ejecting the plastic product by the ejector pin 41, which can meet the high requirements of higher quality plastic products for the ejection process, when the ejector pin 41 ejects the plastic product, the second circular sleeve 304 moves into the first circular sleeve 301 and will squeeze the spring 308 through the first plane bearing 307, when the ejection action is completed, the spring 308 will rebound when the ejector pin 41 returns to the initial position under the action of the hydraulic cylinder 102, and the compressed air inside the first circular sleeve 301 and the second circular sleeve 304 will release the stored elastic potential energy simultaneously when the pressure is lost, thereby pushing the second circular sleeve 304 to reset, waiting for the next work, and when the second circular sleeve 304 moves out to approach the initial position, the first communication hole 309 and the second communication hole 310 on the surface of the first circular sleeve 301 and the second circular sleeve 304 coincide, thereby making the inside and outside air communicate, supplementing the energy loss of air compression,And 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 is in the straightened state, the function of limiting the maximum stroke of the second circular sleeve 304 is played, the overall structure is simple, the design is reasonable, the stability of the device during long-term use can be effectively ensured, and during use, when the piston 203 compresses the nitrogen in the gas storage pipe 201, the first circular sleeve 301 will be close to the gas storage pipe 201, at this time, the second rotating seat 504 and the first rotating seat 503 will be synchronized to approach, and the first connecting rod 501 and the second connecting rod 502 are rotated outward, thereby making the first elastic ring 507 and the second elastic ring 508 sleeved in the first outer groove 505 and the second outer groove 506 be stretched, and after the ejector pin 41 resets, the nitrogen in the gas storage pipe 201 pushes the piston 203 back after losing pressure, at this time, the elastic force generated by the first elastic ring 507 and the second elastic ring 508 will be re-tightened The first connecting rod 501 and the second connecting rod 502 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, ensuring the reliability of the device during use.

[0044] The wiring diagram of the hydraulic cylinder 102 in the application belongs to the common knowledge in the art, and its working principle is a known technology, and the model is selected according to actual use, so the control mode and wiring arrangement of the hydraulic cylinder 102 will not be explained in detail.

[0045] Although the application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacements to part of the technical features, and any modification, equivalent replacement, improvement, etc. within the spirit and principles of the application shall be included in the protection scope of the application.

Claims

1. A flexible ejection device for injection molding machines, comprising an outer frame assembly (1), a first buffer assembly (2), a second buffer assembly (3), a reset assembly (5) and a limiting assembly (6), characterized in that: The first buffer assembly (2), the second buffer assembly (3), the reset assembly (5) and the limiting assembly (6) are arranged in the inside of the outer frame assembly (1), the top of the second buffer assembly (3) is provided with a second plane bearing (4), and the top of the second plane bearing (4) is fixedly provided with a thimble (41); The outer frame assembly (1) comprises an outer shell (101), and the inside of the outer shell (101) is slidably provided with a push plate (103); The first buffer assembly (2) is provided in plurality and is used for flexibly pushing the thimble (41) and comprises a gas storage pipe (201); The second buffer assembly (3) is arranged on the right side of the first buffer assembly (2) and is used for flexibly pushing the thimble (41) and comprises a first circular sleeve (301) and a second circular sleeve (304), the bottom of the first circular sleeve (301) is fixedly provided with a sealing bottom plate (302), the top of the second circular sleeve (304) is provided with a sealing top plate (303), the inner wall of the first circular sleeve (301) is provided with an inner thread (306), the outer surface of the second circular sleeve (304) is provided with an outer thread (305), and the first circular sleeve (301) and the second circular sleeve (304) are threadedly connected through the inner thread (306) and the outer thread (305); The reset assembly (5) is arranged between the outer surfaces of the second buffer assembly (3) and the first buffer assembly (2) and is used for pushing the second buffer assembly (3) to reset and comprises a first connecting rod (501) and a second connecting rod (502); The limiting assembly (6) is arranged in the inside of the second buffer assembly (3) and comprises a connecting rope (603); The left surface of the outer shell (101) is provided with a hydraulic cylinder (102), the telescopic end of the hydraulic cylinder (102) penetrates through the outer shell (101) and is fixedly connected with the push plate (103), the right surface of the outer shell (101) is provided with a fixed plate (104), a plurality of ejection holes (105) are formed in the outer surface of the fixed plate (104), and the outer surface of the thimble (41) and the inner wall of the ejection hole (105) are slidably attached; A plurality of the gas storage pipes (201) are fixedly arranged on the right surface of the push plate (103), the right end of the gas storage pipe (201) is fixedly provided with a sealing plate (202), the inside of the gas storage pipe (201) is filled with nitrogen, the outer surface of the gas storage pipe (201) is embedded with a gas injection nozzle (205) near the left side, and the inner wall of the gas storage pipe (201) is arranged with a piston (203) near the right side; The right surface of the piston (203) is fixedly connected with a push rod (204), the right end of the push rod (204) penetrates through the sealing plate (202) and extends to the right, the right end of the push rod (204) is fixedly connected with the left end of the sealing bottom plate (302), and the right surface of the sealing top plate (303) is connected with the left surface of the second plane bearing (4).

2. A flexible ejection device for an injection molding machine as defined in claim 1, wherein: The outer surface of the first circular sleeve (301) is symmetrically provided with a first communication hole (309) near the right end, and the outer surface of the second circular sleeve (304) is symmetrically provided with a second communication hole (310) near the left end; the first communication hole (309) and the second communication hole (310) are coincident in position when the second circular sleeve (304) is in the initial position; and the outer diameter of the first circular sleeve (301) is consistent with the outer diameter of the gas storage pipe (201).

3. A flexible ejection apparatus for an injection molding machine as defined in claim 2, wherein: The left end of the second circular sleeve (304) is provided with a first plane bearing (307), and the left surface of the first plane bearing (307) is fixedly connected with a spring (308); the left end of the spring (308) abuts against the right surface of the sealing bottom plate (302), and the middle part of the spring (308) is in a contracted state.

4. A flexible ejection apparatus for an injection molding machine as defined in claim 3, wherein: The right end of the connecting rope (603) is fixedly connected with a first bolt cap (601), and the left end of the connecting rope (603) is fixedly connected with a second bolt cap (602); the first bolt cap (601) is threadedly connected at the center of the left surface of the sealing top plate (303), the second bolt cap (602) is threadedly connected at the center of the right surface of the sealing bottom plate (302), and the connecting rope (603) is located inside the spring (308).

5. A flexible ejection apparatus for an injection molding machine as defined in claim 4, wherein: The right end of the first connecting rod (501) and the left end of the second connecting rod (502) are rotationally connected through a rotating pin; the left end of the first connecting rod (501) is rotationally connected with a first rotating seat (503) through a rotating pin; the right end of the second connecting rod (502) is rotationally connected with a second rotating seat (504) through a 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 first rotating seat (503) and the second rotating seat (504) are in position correspondence.

6. A flexible ejection apparatus for an injection molding machine as defined in claim 5, wherein: The outer surface of the first connecting rod (501) is provided with a first outer groove (505), and 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).

7. A method of using a flexible ejection device for an injection molding machine, characterized in that, The flexible ejection device for an injection molding machine of claim 6 is used, and the following steps are included: S1, when the injection molding machine is completed, the plastic product is cooled and formed in the mold cavity, and needs to be ejected, the hydraulic cylinder (102) is started to push the push plate (103) inside the shell (101) to move towards the mold, at this time, under the pushing of the push plate (103), a plurality of ejector pins (41) will push the plastic product in different positions outside through the ejection holes (105) on the surface of the fixed plate (104); S2, the ejector pins (41) in different positions will be subjected to different forces of the reaction force, under the continuous thrust of the hydraulic cylinder (102) and the reaction force generated during the demolding process of the plastic product, the sealing top plate (303) connected by the second plane bearing (4) will apply pressure to the second circular sleeve (304), at this time the second circular sleeve (304) will shrink towards 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) will be in a state of rotation during the movement in the first circular sleeve (301), so the moving speed of the second circular sleeve (304) 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 a state where it cannot be compressed, in this process, the rigid push of the hydraulic cylinder (102) to the ejector pin (41) will be converted into a flexible push, and then the plastic product will be perfectly pushed out of the cavity; S4, 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 only start to compress the nitrogen gas inside the gas storage pipe (201) by pushing the piston (203) inside the gas storage pipe (201) through the push rod (204), and the additional stroke obtained by compressing the nitrogen gas will assist the movement of the ejector pin (41).

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