A dosing device and a dosing method for an injection molding machine

Abstract

The application provides a quantitative feeding device and feeding method of an injection molding machine, and aims to solve the technical problems of poor feeding stability, poor filtering and arch breaking effect, and easy feeding interruption of the existing injection molding machine feeding system. The device comprises a storage tank, a waste cylinder, a filter frame, a plurality of inverted conical filter plates and a temporary storage cavity. The discharge end of the waste cylinder penetrates the storage tank and is in communication with a crushing mechanism. The filter hole diameter of the filter plate gradually decreases along the powder movement direction, and the end part is provided with a discharge port aligned with the feed inlet of the waste cylinder. The top of the filter frame is rotationally connected with the top of the storage tank through a rotating shaft. The rotating shaft is internally threadedly connected with an axially movable screw rod. The screw rod penetrates all the discharge ports and is provided with a plurality of blocking plates. Through the integrated design of "filtering, agglomeration, crushing and feeding", and the cooperation of intelligent sensing control, the application realizes the automatic interception and processing of agglomeration, ensures the continuous and stable feeding, and improves the production efficiency and product qualification rate.

Description

Technical Field

[0001] This invention relates to the field of injection molding machine feeding technology, specifically to a quantitative feeding device and feeding method for an injection molding machine. Background Technology

[0002] During the injection molding process, a fixed amount of injection molding powder (such as plastic granules, modified powder, etc.) needs to be continuously supplied into the barrel. The uniformity and stability of the supply directly determine the quality of the injection molded products, specifically affecting key indicators such as the product's dimensional accuracy, surface finish, and mechanical properties. Therefore, the feeding system is an indispensable core component of the injection molding production line.

[0003] Currently, most injection molding machines use a direct material feeding system from a storage tank. In some cases, a simple filter is used to remove impurities before feeding. However, these existing feeding systems have some drawbacks in practical industrial applications, which limit the efficiency and product yield of injection molding production. The specific problems are as follows:

[0004] Firstly, powder agglomeration leads to supply interruptions. When injection molding powder is stored in the storage tank, it is easily affected by environmental and storage conditions such as moisture absorption and compression, resulting in agglomeration. The agglomerated powder particles are usually larger than 5mm. If they are directly fed into the injection molding machine barrel, they can easily cause blockage at the barrel inlet, forcing an interruption in the supply process. At this time, manual shutdown is required for cleaning, which not only increases the labor intensity but also seriously affects the continuity and efficiency of production.

[0005] Secondly, the filtration mechanism has poor filtration efficiency and is prone to clogging. Existing feeding systems equipped with filtration structures mostly use flat filter screens. During use, clumps of powder easily adhere to the surface of this type of filter screen, causing it to clog quickly; and after clogging, the filter screen needs to be disassembled for cleaning, which is a cumbersome process and further reduces production efficiency.

[0006] Third, the methods for breaking up bridging are ineffective and energy-intensive. Regarding the problem of powder agglomeration in storage tanks, existing methods for breaking up bridging (such as vibration breaking, air cannon breaking, and mixing and pulverizing) only loosen the powder adhering to the tank walls; they cannot effectively break up existing hard bridging, resulting in limited effectiveness. Mixing and pulverizing, on the other hand, can compact the powder on the filter screen surface.

[0007] In summary, existing injection molding machine feeding systems suffer from problems such as poor feeding stability, inadequate filtration, and poor arch breaking effects, which seriously affect injection molding production efficiency and product quality. Therefore, developing an injection molding machine feeding system that can solve the above problems has become an urgent technical challenge in this field. Summary of the Invention

[0008] The purpose of this invention is to provide a quantitative feeding device and feeding method for an injection molding machine, which does not have at least one of the disadvantages mentioned above.

[0009] To achieve the above objectives, the present invention provides the following technical solution: a quantitative feeding device for an injection molding machine, comprising a storage tank, a waste cylinder fixed inside the storage tank, a filter frame rotatably connected to the waste cylinder, a plurality of filter plates fixed to the filter frame and in the shape of an inverted cone, and a temporary storage cavity disposed at the lower part of the storage tank; the discharge end of the waste cylinder passes through the storage tank and is connected to a crushing mechanism; the pore size of the filter plates gradually decreases along the direction of powder movement, and each filter plate has a discharge port in the middle that is aligned with the inlet of the waste cylinder, the lowermost discharge port being in contact with the inlet; the top of the filter frame is rotatably connected to the top of the storage tank via a rotating shaft, the internal thread of the rotating shaft is connected to a screw that can move axially, the screw passes through all the discharge ports, and a plurality of baffle plates that cooperate with the discharge ports and the inlet are installed on the screw.

[0010] Furthermore, both the discharge port and the inlet are provided with steps, and when the baffle plate is engaged with the discharge port or the inlet, the baffle plate abuts against the steps.

[0011] Furthermore, each of the baffle plates is slidably connected to the optical axis section of the screw, and each of the baffle plates has an upper convex plate and a lower convex plate at both ends. When the upper convex plate abuts against the baffle plate, there is an active gap between the lower convex plate and the baffle plate. The active gap h is greater than the distance d that the screw rises when the filter frame rotates X revolutions, where X is a preset parameter and X>1.

[0012] Furthermore, it also includes a control module and a laser sensor for detecting whether there is a powder rat hole volume inside the temporary storage cavity; the laser sensor is electrically connected to the control module, and the control module is used to control the rotation state of the rotating shaft;

[0013] When the volume of the powder rat hole detected by the laser sensor is greater than the first threshold, the powder stops flowing in from the inlet of the storage tank, and the control module drives the rotating shaft to reciprocate within X circles.

[0014] When the volume of the powder rat hole detected by the laser sensor is greater than the second threshold, the powder stops flowing in from the inlet of the storage tank. The control module drives the rotating shaft to reciprocate A cycles within X circles, and then drives the rotating shaft to rotate in one direction, so that the baffle plate separates from the outlet and the inlet.

[0015] Wherein, the first threshold is less than the second threshold.

[0016] Furthermore, the storage tank is equipped with several capacity sensors, each of which is used to detect the residual powder volume height on each of the filter plates, and all of the capacity sensors are connected to the control module.

[0017] When the volume of the powder mouse hole detected by the laser sensor is greater than the first threshold, and the control module drives the rotating shaft to reciprocate within X revolutions, the value detected by the capacity sensor tends to stabilize.

[0018] If the height of the agglomerated powder is greater than 1 / B of the height of the baffle plate, the control module drives the rotating shaft to rotate in one direction, so that the baffle plate is separated from the outlet and the inlet; otherwise, the powder is started to flow in from the inlet of the storage tank; wherein, B is adjusted according to the taper adaptability of the filter plate, and 2≤B≤3.

[0019] Furthermore, along the direction of powder discharge, h gradually increases, and the difference between any two adjacent h values ​​is greater than d.

[0020] Furthermore, the baffle plate and the step are fixedly connected to each other with permanent magnets that attract each other.

[0021] Furthermore, the top of the storage tank is provided with a fixed plate, the top of the screw is fixedly connected with a square shaft, the square shaft is slidably connected to the fixed plate, and the fixed plate is provided with a drive assembly for driving the rotating shaft to rotate.

[0022] Furthermore, the volume of the temporary storage cavity is greater than the internal volume of the storage tank, which is at the same height as the filter frame.

[0023] The present invention also provides a quantitative feeding method for an injection molding machine, based on the above-mentioned quantitative feeding device for the injection molding machine, comprising the following steps:

[0024] S1: The injection molding powder is stored in the storage tank through the inlet at the top of the storage tank. Under the action of gravity, the powder falls sequentially onto several layers of filter plates on the filter frame, and then falls into the temporary storage chamber for storage. Finally, it is discharged quantitatively from the bottom of the storage tank.

[0025] S2: When the volume of the powder rat hole detected by the laser sensor is greater than the first threshold, the powder is stopped from flowing in from the feed inlet of the storage tank, and the control module drives the rotating shaft to reciprocate within X circles, so that the agglomerated powder is concentrated in the middle of the filter plate.

[0026] S2.1: During S2, when the value detected by the capacity sensor tends to stabilize; if the detected capacity height of the powder is greater than 1 / B of the height of the baffle plate, the control module drives the rotating shaft to rotate in one direction, so that the baffle plate is separated from the outlet and inlet, thereby allowing the agglomerated powder to flow out from the waste cylinder; otherwise, the powder is started to flow in from the inlet of the storage tank.

[0027] S3: When the volume of the powder rat hole detected by the laser sensor is greater than the second threshold, the powder stops flowing in from the inlet of the storage tank. After the control module drives the rotating shaft to reciprocate A cycles in X circles, it drives the rotating shaft to rotate in one direction, so that the baffle plate separates from the outlet and the inlet, thereby allowing the agglomerated powder to flow out from the waste cylinder.

[0028] S4: During the S1-S3 process, the temporary storage chamber ensures stable material output, thereby meeting the quantitative requirements.

[0029] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0030] 1. This invention uses an inverted conical filter plate in conjunction with a rotatable filter frame. It utilizes gravity and centrifugal force to concentrate agglomerated powder towards the central discharge port. Combined with a waste cylinder and a crushing mechanism, it achieves a closed-loop treatment of agglomerated material interception, concentration, and crushing. Compared with existing methods such as vibration arch breaking and air cannon arch breaking, it can effectively break hard agglomerated material and prevent agglomerated material from clogging the feed inlet at the source.

[0031] 2. The filter plate adopts a gradient design where the pore size gradually decreases along the direction of powder movement, achieving graded filtration. The upper layer intercepts large clumps, while the lower layer filters fine impurities, reducing the load on a single-stage filtration process. In conjunction with the rotation of the filter frame, static adhesion of clumps to the filter pore surface is prevented, achieving dynamic self-cleaning, significantly reducing the probability of filter clogging, eliminating the need for frequent disassembly and cleaning, and improving production efficiency.

[0032] 3. By combining laser sensors, capacity sensors and control modules, real-time detection of mouse hole volume and agglomeration accumulation is achieved. Combined with dual-threshold graded control logic, operations such as feeding start and stop, filter frame rotation and baffle opening and closing are automatically completed without manual intervention for judgment and cleaning, reducing labor intensity and improving the level of production automation. Attached Figure Description

[0033] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0034] Figure 1This is a schematic diagram of the overall structure of the present invention;

[0035] Figure 2 This is a cross-sectional schematic diagram of the present invention.

[0036] The components are: 1. Storage tank; 2. Waste cylinder; 3. Drive assembly; 4. Fixing plate; 5. Upper convex plate; 6. Filter plate; 7. Baffle plate; 8. Lower convex plate; 9. Rotating shaft; 10. Square shaft; 11. Filter frame. Detailed Implementation

[0037] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided below.

[0038] Example

[0039] Currently, most injection molding machines use a direct material feeding system from a storage tank. In some cases, a simple filter is used to remove impurities before feeding. However, these existing feeding systems have some drawbacks in practical industrial applications, which limit the efficiency and product yield of injection molding production. The specific problems are as follows:

[0040] Firstly, powder agglomeration leads to supply interruptions. When injection molding powder is stored in the storage tank, it is easily affected by environmental and storage conditions such as moisture absorption and compression, resulting in agglomeration. The agglomerated powder particles are usually larger than 5mm. If they are directly fed into the injection molding machine barrel, they can easily cause blockage at the barrel inlet, forcing an interruption in the supply process. At this time, manual shutdown is required for cleaning, which not only increases the labor intensity but also seriously affects the continuity and efficiency of production.

[0041] Secondly, the filtration mechanism has poor filtration efficiency and is prone to clogging. Existing feeding systems equipped with filtration structures mostly use flat filter screens. During use, clumps of powder easily adhere to the surface of this type of filter screen, causing it to clog quickly; and after clogging, the filter screen needs to be disassembled for cleaning, which is a cumbersome process and further reduces production efficiency.

[0042] Third, the methods for breaking up bridging are ineffective and energy-intensive. Regarding the problem of powder agglomeration in storage tanks, existing methods for breaking up bridging (such as vibration breaking, air cannon breaking, and mixing and pulverizing) only loosen the powder adhering to the tank walls; they cannot effectively break up existing hard bridging, resulting in limited effectiveness. Mixing and pulverizing, on the other hand, can compact the powder on the filter screen surface.

[0043] Therefore, based on the above issues, please refer to... Figures 1-2This invention discloses a quantitative feeding device for an injection molding machine, comprising a storage tank 1, a waste cylinder 2 fixed inside the storage tank 1, a filter frame 11 rotatably connected to the waste cylinder 2, several filter plates 6 fixed to the filter frame 11 and in the shape of an inverted cone, and a temporary storage cavity located at the lower part of the storage tank 1; the discharge end of the waste cylinder 2 passes through the storage tank 1 and is connected to a crushing mechanism; the pore size of the filter plates 6 gradually decreases along the direction of powder movement, and each filter plate 6 has a discharge port in the middle aligned with the inlet of the waste cylinder 2, with the lowermost discharge port fitting against the inlet; the top of the filter frame 11 is connected by a rotating shaft. The rotating shaft 9 is rotatably connected to the top of the storage tank 1. The internal thread of the rotating shaft 9 is connected to a screw that can move axially. The screw passes through all the discharge ports, and several baffles 7 that cooperate with the discharge ports and the inlet ports are installed on the screw. The inverted conical filter plate 6 cooperates with the rotating filter frame 11. Gravity is used to concentrate the agglomerates, and the gradual filter holes realize graded filtration. The rotating shaft 9-screw-baffles 7 control the discharge of agglomerates, while the temporary storage chamber ensures continuous feeding. Therefore, it effectively solves the problems of agglomerate blockage, poor filtration effect, and feeding interruption, and realizes the integration of "filtration-agglomeration-crushing-feeding", which improves the feeding stability and production efficiency.

[0044] Specifically, when there is a large amount of agglomerated powder, rotating the shaft 9 will cause the screw to move vertically, thereby driving the baffle plate 7 away from the discharge port and the feed port, so that the agglomerated powder flows into the waste cylinder 2 and is discharged. In order to prevent the unagglomerated powder from flowing out of the waste cylinder 2, in one embodiment, each baffle plate 7 is slidably connected to the optical axis section of the screw, and each baffle plate 7 has an upper convex plate 5 and a lower convex plate 8 at both ends. When the upper convex plate 5 abuts against the baffle plate 7, there is a movable gap between the lower convex plate 8 and the baffle plate 7. The movable gap h is greater than the distance the screw rises when the filter frame 11 rotates X times. d and X are preset parameters, and X>1; where the value of X can be adapted according to the powder diameter or the model of the motor used to drive the rotating shaft 9. In this embodiment, X is 3. When it is necessary to discharge the agglomerated powder, the main shaft first rotates back and forth within the range of X revolutions, so that the unagglomerated powder on the baffle plate 7 falls into the temporary storage cavity, leaving only the agglomerated powder on the baffle plate 7. Then, the rotating shaft 9 can be driven to rotate in one direction, thereby driving the baffle plate 7 away from the discharge port and the feed port, so that the agglomerated powder flows into the waste cylinder 2 and is discharged; to prevent the agglomerated powder from flowing away.

[0045] To improve the efficiency of unagglomerated powder falling into the temporary storage chamber during reciprocating motion, adjacent filter plates 6 are connected by vertical rods. During rotation, the vertical rods agitate the unagglomerated powder within the filter plates 6, thereby increasing the efficiency of unagglomerated powder falling into the temporary storage chamber. Steps are provided on both the discharge port and the inlet. When the baffle plate 7 is engaged with the discharge port or inlet, it abuts against the steps to ensure a stable seal. In the process of unagglomerated powder falling into the temporary storage chamber mentioned above, the technical solution of this invention also includes a control module and a mechanism for detecting whether the contents of the temporary storage chamber are agglomerated. A laser sensor detects the volume of the powder rodent hole. The laser sensor is electrically connected to a control module, which controls the rotation of the rotating shaft 9. The method of detecting the volume of the powder rodent hole is based on the fact that, to ensure quantitative conveying, the volume of powder decreasing in the temporary storage chamber is constant. If excessive agglomeration occurs in the powder, it indicates that the amount of powder falling from the filter frame 11 into the temporary storage chamber will be less than the amount of powder decreasing in the temporary storage chamber. Therefore, rodent holes will form between the two. When the rodent hole is larger than a certain volume, it may cause the temporary storage chamber to be unable to guarantee quantitative discharge. Therefore, in one embodiment of the present invention:

[0046] When the volume of the powder rat hole detected by the laser sensor is greater than the first threshold, the flow of powder from the inlet of storage tank 1 will be stopped. The control module drives the rotating shaft 9 to reciprocate within X revolutions, thereby concentrating the agglomerated powder in the middle of the filter plate 6 to prevent the agglomerated powder from spreading on the filter plate 6 and causing serious blockage. After the agglomerated powder is concentrated in the middle of the filter plate 6, the agglomerated powder will not be discharged. When the powder is started to flow from the inlet of storage tank 1, the amount flowing in at the initial stage will be greater than the original amount, which is used to replenish the powder volume that has decreased in the temporary storage chamber during the above process.

[0047] When the volume of the powder burrow detected by the laser sensor is greater than the second threshold, and the first threshold is less than the second threshold, it indicates severe blockage. At this point, the flow of powder from the inlet of storage tank 1 will be stopped. The control module drives the rotating shaft 9 to reciprocate A cycles within X circles, dropping the un-clumped powder into the temporary storage chamber. The value of A is determined by the capacity sensor. When the capacity sensor detects that the powder volume in a filter plate 6 remains unchanged, the reciprocating rotation will stop. At this point, A is the cumulative number of reciprocating rotations. Then, the rotating shaft 9 is driven to rotate in one direction, separating the baffle plate 7 from the outlet and inlet to discharge the clumped powder. Then, the rotating shaft 9 rotates in the opposite direction, aligning the baffle plate 7 with the outlet and inlet, and then the flow of powder from the inlet of storage tank 1 can be started. At this point, the initial inflow will be greater than the original inflow to replenish the powder volume that has decreased in the temporary storage chamber during the above process.

[0048] In one embodiment, the storage tank 1 is equipped with several capacity sensors, each used to detect the residual powder volume height on each filter plate 6. All capacity sensors are connected to the control module. Therefore, when the volume of the powder burrow detected by the laser sensor is greater than a first threshold, and the control module drives the rotating shaft 9 to reciprocate within X revolutions, when the value detected by the capacity sensor tends to stabilize, if the volume height of the agglomerated powder is greater than 1 / B of the baffle plate height, the control module drives the rotating shaft to rotate in one direction, separating the baffle plate from the outlet and inlet; otherwise, the powder flows in from the inlet of the storage tank. Wherein, B depends on the filter plate... The taper can be adjusted to adapt to different conditions, with 2≤B≤3. The ratio of "powder capacity height to baffle height 1 / B" is used as the judgment threshold to dynamically select "separate baffle (discharge)" or "replenish material", avoiding the coarse control of "full flow / full cut-off" and reducing the risk of material blockage and material interruption. At the same time, it enhances the versatility of the solution. The B value can be adaptively adjusted according to the taper of the inverted conical filter plate, so that the solution can be adapted to filter plate designs with different tapers without redesigning the control logic due to taper changes. It also improves the powder processing efficiency, avoids excessive replenishment (saving raw materials) and insufficient discharge (ensuring continuous production), and reduces the ineffective movement of the shaft and baffle, reducing mechanical wear.

[0049] In the above scheme, the core function of B is to define the threshold (1 / B) for determining whether there is enough powder to discharge. Its value range is directly related to the structural characteristics of the inverted conical filter plate, the powder accumulation pattern, and the effectiveness of the control logic. If this range is missing:

[0050] If the value of B is too small (B<2), 1 / B>0.5, the judgment threshold is too high (the powder height must exceed 50% of the baffle height before discharge); the inverted cone shape is wider at the top and narrower at the bottom. When the height is more than halfway up, the agglomerated powder has already accumulated in the upper part of the filter plate. At this time, the agglomerated powder after reaching the critical value will grow rapidly with the same increase in height; at this time, the volume will increase and the pressure will increase, and the discharge is prone to blockage due to extrusion;

[0051] The value of B is too large (B>3), 1 / B<0.33, and the judgment threshold is too low (the material is discharged when the height of the powder exceeds 33% of the height of the baffle plate); the space at the bottom of the inverted cone is narrow, and the amount of powder that clumps is small when the height does not reach a certain value. The discharge will lead to unnecessary power consumption waste due to insufficient material, and the frequent triggering of discharge / replenishment switching will increase mechanical wear and cause control logic disorder.

[0052] Furthermore, if B has no range restriction, it will lose its adaptability. B needs to match the normal taper range of the inverted conical filter plate (in industrial scenarios, the taper of the inverted conical filter plate is mostly 30°~60°). The range 2≤B≤3 can basically cover the powder accumulation pattern within this taper range, ensuring the rationality of the judgment threshold. If there is no restriction, B may deviate from the actual needs, causing the solution to fail.

[0053] The core reason for choosing a value of 2 ≤ B ≤ 3 for B is that the core characteristic of an inverted conical filter plate is that it is "wider at the top and narrower at the bottom." The accumulation of powder on its surface follows the rule of "slow capacity growth at low heights, and rapid capacity growth after reaching a critical height." A value of 2 ≤ B ≤ 3 is the optimal range to match this rule, covering the needs of typical industrial applications. In industrial applications, the taper design of the inverted conical filter plate needs to balance "powder flowability" and "accumulation stability." The taper is mostly between 30° and 60°, corresponding to a critical powder accumulation height falling between 1 / 3 and 1 / 2 of the baffle plate height. This range ensures normal discharge of agglomerated powder while avoiding increased energy consumption, and it is also compatible with filter plates of different tapers, ensuring the versatility and control stability of the solution.

[0054] In one embodiment, along the direction of powder discharge, h gradually increases, and the difference between any two adjacent h values ​​is greater than d, thereby achieving the sequential falling of agglomerated powder. During the rotation of the shaft 9, the baffle plate 7 moves sequentially from top to bottom from the discharge port and the inlet, thus achieving the sequential falling of the agglomerated powder. This sequential falling method avoids a large amount of agglomerated powder falling at once, which could cause significant impact on subsequent processes, ensuring the stability and continuity of the feeding process. During the sequential falling of the agglomerated powder, the baffle plate 7 regularly engages and disengages with the discharge port and the inlet, controlling the falling rhythm of the agglomerated powder.

[0055] Specifically, during actual operation, when the rotating shaft 9 rotates, the screw drives the baffle plate 7 to rise axially. As the clearance h between each baffle plate 7 gradually increases from top to bottom, the baffle plate 7 moves out from the discharge port and inlet sequentially from top to bottom, guiding the agglomerated powder on each filter plate 6 to fall sequentially. This sequential falling method effectively avoids a large amount of agglomerated powder falling all at once, causing significant impact on the subsequent crushing mechanism and conveying pipeline; it also prevents the crushing mechanism from overloading and shutting down due to excessive instantaneous feed, and avoids secondary blockage in the conveying pipeline due to agglomerated material accumulation, thus ensuring the stability and continuity of the feeding process. Furthermore, during the sequential falling of the agglomerated powder, the baffle plate 7 regularly engages and disengages with the discharge port and inlet, precisely controlling the falling rhythm of the agglomerated powder, further improving the controllability of the entire feeding system and ensuring efficient and coordinated operation of all components.

[0056] As the baffle plates 7 move out from the discharge port and the inlet in sequence from top to bottom, guiding the agglomerated powder on each layer of filter plates 6 to fall sequentially, the filter frame 11 will be in reciprocating rotation while the previous baffle plate 7 is moved out and the next baffle plate 7 is not moved out. This ensures that the agglomerated powder on the filter plate 6 corresponding to the moved baffle plate 7 can fall fully into the filter plate 6 below, thereby improving the discharge quality of the agglomerated powder.

[0057] In one embodiment, the baffle plate 7 and the step are fixedly connected with mutually attractive permanent magnets; this enhances the sealing performance, effectively preventing powder from entering the waste cylinder 2 through gaps during normal feeding, reducing material waste, and improving the quantitative accuracy of feeding; the top of the storage tank 1 is provided with a fixing plate 4, and the top of the screw is fixedly connected with a square shaft 10, which is slidably connected to the fixing plate 4, thereby restricting the rotation of the screw and realizing the vertical movement of the screw; the fixing plate 4 is provided with a drive assembly 3 for driving the rotating shaft 9 to rotate, and the drive assembly 3 can adopt a common motor-driven belt drive mechanism to realize the rotation of the rotating shaft 9; in addition, the volume of the temporary storage chamber is larger than the internal volume of the storage tank 1, which is the same height as the filter frame 11, ensuring that the temporary storage chamber can store a sufficient amount of qualified powder, and its storage capacity can meet the feeding needs of the injection molding machine for the entire process of agglomeration treatment (usually 10-15 minutes). In actual operation, when the agglomeration treatment process is initiated, the feeding and filtering channels of storage tank 1 are temporarily closed, but the feeding channels of the temporary storage chamber and the injection molding machine barrel remain unobstructed. The qualified powder stored in the temporary storage chamber is continuously fed to the injection molding machine, achieving synchronization between the agglomeration treatment and the feeding process. This design completely solves the problem of feeding interruption during agglomeration treatment in existing technologies, ensuring the continuous operation of the injection molding machine. At the same time, the continuous and stable feeding ensures the stability of the temperature and pressure fields inside the injection molding machine barrel, effectively avoiding product quality problems caused by feeding interruptions, and significantly improving production efficiency and product quality stability.

[0058] The present invention also provides a quantitative feeding method for an injection molding machine, based on the above-mentioned quantitative feeding device for the injection molding machine, comprising the following steps:

[0059] S1: The injection molding powder is stored in the storage tank 1 through the feed port at the top of the storage tank 1. Under the action of gravity, the powder falls sequentially onto several layers of filter plates 6 on the filter frame 11, and then falls into the temporary storage chamber for storage. Then, it is quantitatively discharged from the bottom of the storage tank 1.

[0060] S2: When the volume of the powder rat hole detected by the laser sensor is greater than the first threshold, the powder flows in from the inlet of the storage tank 1 and the control module drives the rotating shaft 9 to reciprocate within X circles, so that the agglomerated powder is concentrated in the middle of the filter plate 6.

[0061] S2.1: During process S2, when the value detected by the capacity sensor tends to stabilize; if the detected capacity height of the powder is greater than 1 / B of the height of the baffle plate 7, the control module drives the rotating shaft 9 to rotate in one direction, so that the baffle plate 7 is separated from the discharge port and the feed port, thereby allowing the agglomerated powder to flow out from the waste cylinder 2; otherwise, the powder is started to flow in from the feed port of the storage tank 1.

[0062] S3: When the volume of the powder rat hole detected by the laser sensor is greater than the second threshold, the powder stops flowing in from the inlet of the storage tank 1. The control module drives the rotating shaft 9 to reciprocate A cycles in X circles, and then drives the rotating shaft 9 to rotate in one direction, so that the baffle plate 7 is separated from the outlet and the inlet, thereby allowing the agglomerated powder to flow out from the waste cylinder 2.

[0063] S4: During the S1-S3 process, the temporary storage chamber ensures stable material output, thereby meeting the quantitative requirements.

[0064] It should be noted that when a component is said to be "fixed to" another component, it can be directly attached to the other component or there may be an intervening component. When a component is said to be "connected to" another component, it can be directly connected to the other component or there may be an intervening component. The terms "upper," "lower," "left," "right," "front," "back," and similar expressions used in this document are for illustrative purposes only.

[0065] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A quantitative feeding device for an injection molding machine, characterized in that, The system includes a storage tank, a waste cylinder fixed inside the storage tank, a filter frame rotatably connected to the waste cylinder, several inverted conical filter plates fixed to the filter frame, and a temporary storage chamber located at the bottom of the storage tank. The discharge end of the waste cylinder passes through the storage tank and is connected to a crushing mechanism. The pore size of the filter plates gradually decreases along the direction of powder movement, and each filter plate has a discharge port in the middle that is aligned with the inlet of the waste cylinder. The discharge port at the bottom is in contact with the inlet. The top of the filter frame is rotatably connected to the top of the storage tank via a rotating shaft. The rotating shaft is internally threaded with a screw that can move axially. The screw passes through all the discharge ports, and several baffles that cooperate with the discharge ports and the inlet are installed on the screw. Both the discharge port and the inlet are provided with steps. When the baffle plate is engaged with the discharge port or the inlet, the baffle plate abuts against the steps. Each of the baffle plates is slidably connected to the optical axis section of the screw, and each of the baffle plates has an upper convex plate and a lower convex plate at both ends. When the upper convex plate abuts against the baffle plate, there is a movable gap h between the lower convex plate and the baffle plate. The movable gap h is greater than the distance d that the screw rises when the filter frame rotates X revolutions, where X is a preset parameter and X>1.

2. The quantitative feeding device for an injection molding machine according to claim 1, characterized in that, It also includes a control module and a laser sensor for detecting the volume of powder rat holes inside the temporary storage chamber; the laser sensor is electrically connected to the control module, which is used to control the rotation state of the rotating shaft; the method of detecting the volume of powder rat holes is because, in order to ensure quantitative delivery, the volume of powder decreasing in the temporary storage chamber is constant. If there is too much agglomeration in the powder, it means that the amount of powder falling from the filter plate into the temporary storage chamber will be less than the amount of powder decreasing in the temporary storage chamber. Therefore, rat holes will be generated between the two. When the rat hole is larger than a certain volume, it may cause the temporary storage chamber to be unable to guarantee quantitative discharge. When the volume of the powder rat hole detected by the laser sensor is greater than the first threshold, the powder stops flowing in from the inlet of the storage tank, and the control module drives the rotating shaft to reciprocate within X circles. When the volume of the powder rat hole detected by the laser sensor is greater than the second threshold, the powder stops flowing in from the inlet of the storage tank. The control module drives the rotating shaft to reciprocate A cycles within X circles, and then drives the rotating shaft to rotate in one direction, so that the baffle plate separates from the outlet and the inlet. Wherein, the first threshold is less than the second threshold.

3. The quantitative feeding device for an injection molding machine according to claim 2, characterized in that, The storage tank is equipped with several capacity sensors, each of which is used to detect the residual powder volume height on each of the filter plates. All of the capacity sensors are connected to the control module. When the volume of the powder mouse hole detected by the laser sensor is greater than the first threshold, and the control module drives the rotating shaft to reciprocate within X revolutions, the value detected by the capacity sensor tends to stabilize. If the height of the agglomerated powder is greater than 1 / B of the height of the baffle plate, the control module drives the rotating shaft to rotate in one direction, so that the baffle plate is separated from the outlet and the inlet; otherwise, the powder is started to flow in from the inlet of the storage tank; wherein, B is adjusted according to the taper adaptability of the filter plate, and 2≤B≤3.

4. The quantitative feeding device for an injection molding machine according to claim 2, characterized in that, Along the direction of powder discharge, h gradually increases, and the difference between any two adjacent h values ​​is greater than d.

5. The quantitative feeding device for an injection molding machine according to claim 1, characterized in that, The baffle plate and the step are fixedly connected to each other with permanent magnets that attract each other.

6. The quantitative feeding device for an injection molding machine according to claim 1, characterized in that, The top of the storage tank is provided with a fixed plate, the top of the screw is fixed with a square shaft, the square shaft is slidably connected to the fixed plate, and the fixed plate is provided with a drive assembly for driving the rotating shaft to rotate.

7. A quantitative feeding method for an injection molding machine, based on the quantitative feeding device for the injection molding machine as described in claim 3, characterized in that, Includes the following steps: S1: The injection molding powder is stored in the storage tank through the inlet at the top of the storage tank. Under the action of gravity, the powder falls sequentially onto several filter plates on the filter frame, and then falls into the temporary storage chamber for storage. Then, it is discharged quantitatively from the bottom of the storage tank. S2: When the volume of the powder rat hole detected by the laser sensor is greater than the first threshold, the powder is stopped from flowing in from the feed inlet of the storage tank, and the control module drives the rotating shaft to reciprocate within X circles, so that the agglomerated powder is concentrated in the middle of the filter plate. S2.1: During S2, when the value detected by the capacity sensor tends to stabilize; if the detected capacity height of the powder is greater than 1 / B of the height of the baffle plate, the control module drives the rotating shaft to rotate in one direction, so that the baffle plate is separated from the discharge port and the feed port, thereby allowing the agglomerated powder to flow out from the waste cylinder; otherwise, the powder is started to flow in from the feed port of the storage tank. S3: When the volume of the powder rat hole detected by the laser sensor is greater than the second threshold, the powder stops flowing in from the feed inlet of the storage tank. The control module drives the rotating shaft to reciprocate A cycles within X circles, and then drives the rotating shaft to rotate in one direction, so that the baffle plate separates from the discharge port and the feed inlet, thereby allowing the agglomerated powder to flow out from the waste cylinder. S4: During the S1-S3 process, the temporary storage chamber ensures stable material output, thereby meeting the quantitative requirements.

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