Quantitative feeding device for plastic production

Abstract

The invention relates to the technical field of plastic waste recycling equipment, in particular to a quantitative feeding device for plastic production. The device comprises a rack, a recycling box, a crushing device and a material receiving box separated from the rack, a metal umbrella plate is slidably mounted at the lower end of the crushing device, and a hollowed-out frame and a double-air-chamber air bag matched with the hollowed-out frame in outline are arranged in the material receiving box. The first air chamber of the air bag is inflated to form edge pressure-stabilizing sealing, the second air chamber periodically expands and contracts to push the metal umbrella plate to partially move upwards, and mechanical linkage of sealing and pulsation discharging is achieved. The device can be integrated with an industrial visual system, foreign matter and color difference recognition is carried out on recycled plastic, the feeding purity and the intelligent level are improved, and the clean and efficient production requirement for plastic waste recycling is effectively met.

Description

Technical Field

[0001] This invention relates to the field of plastic recycling equipment technology, specifically a quantitative feeding device for plastic production. Background Technology

[0002] Driven by current policies promoting the circular economy and green manufacturing, the recycling of plastic waste has become an important path for the plastics processing industry to achieve resource conservation and environmentally friendly development. The production of recycled plastics typically includes processes such as sorting, crushing, washing, drying, and quantitative feeding. Among these, the quantitative feeding stage directly affects the stability of the subsequent melting and plasticizing process and the consistency of the final product's quality.

[0003] However, due to the wide range of sources and complex composition of recycled plastics, which often contain abnormally colored particles, non-plastic impurities (such as metals, paper, and rubber), or uneven physical properties caused by aging and degradation, higher requirements are placed on the adaptability and reliability of feeding devices. Currently, most plastic quantitative feeding devices on the market adopt mechanical volumetric metering or simple weighing structures, which generally have poor sealing performance and are prone to serious dust emission during crushing and discharge processes, which not only pollutes the working environment but also poses safety hazards.

[0004] More importantly, the quantitative accuracy of such devices is highly dependent on the material's flowability, particle size distribution, and bulk density. However, the physical properties of recycled plastics fluctuate significantly, leading to substantial deviations in the actual feed rate and making it difficult to meet the demands of high-precision production processes. Although industrial vision technology has seen initial applications in material sorting in recent years, with some systems using cameras to identify foreign objects or color differences, these systems are mostly independent front-end detection units. They lack deep integration with downstream feeding mechanisms and cannot dynamically adjust crushing intensity, feeding rhythm, or start / stop logic based on real-time detection results, making it difficult to form effective closed-loop intelligent control.

[0005] Therefore, there is an urgent need for a quantitative feeding device for plastic production to meet the comprehensive needs of clean production, precise feeding and intelligent control in the process of plastic waste recycling. Summary of the Invention

[0006] The purpose of this invention is to provide a quantitative feeding device for plastic production, in order to solve the problems mentioned in the background art, such as poor sealing, serious dust emission, quantitative accuracy greatly affected by material characteristics, insufficient coordination between industrial vision system and feeding mechanism, and difficulty in achieving closed-loop intelligent control.

[0007] To achieve the above objectives, the present invention provides the following technical solution: A quantitative feeding device for plastic production includes a frame, a recycling bin mounted on the frame, a crushing device inside the recycling bin, and a receiving bin placed on the frame, separate from the frame and the recycling bin. A metal umbrella plate is slidably mounted on one end of the crushing device near the receiving bin, the metal umbrella plate being in line-surface contact with the inner wall of the recycling bin. A perforated frame is installed inside the receiving bin, and an airbag is fixedly mounted on the perforated frame. An air source is connected to the outside of the airbag, and the outer contour of the airbag is adapted to the inner surface contour of the metal umbrella plate, enabling it to abut against the inner surface of the metal umbrella plate to form a closed chamber.

[0008] Preferably, the airbag has a first air chamber and a second air chamber that are isolated from each other. The first air chamber is arranged along the circumferential edge of the airbag and is connected to a first air source through a first air inlet pipe. The second air chamber is located in the central area of ​​the airbag and is connected to a second air source through a second air inlet pipe. The first air inlet pipe is equipped with a normally closed solenoid valve, and the outlet ends of the second air inlet pipe and the second air chamber are both equipped with one-way valves, with the working surfaces of the one-way valves on both sides being opposite.

[0009] Preferably, the crushing device includes a bushing rotatably mounted inside the recycling bin, a blade fixedly mounted on the bushing, a servo motor fixedly mounted on the outer wall of the recycling bin, and the output end of the servo motor connected to the bushing via a belt drive.

[0010] Preferably, the crushing device further includes a central shaft, one end of which, near the metal umbrella plate, extends through a bushing and is fixedly fitted with a grinding wheel; wherein, a damping pad is fitted on the central shaft, the damping pad being sandwiched between the bushing and the central shaft to provide axial damping force.

[0011] Preferably, the central shaft is threadedly fitted to the bushing, and the other end of the central shaft also passes through the bushing and is fixedly mounted with a knob. A grinding block is fixedly installed inside the receiving box, and an arc-shaped grinding cavity is opened in the center of the grinding block. The grinding wheel is collinear with the center of the arc-shaped grinding cavity. A spring is sleeved on the central shaft, and the two ends of the spring abut against the bushing and the grinding wheel, respectively.

[0012] Preferably, an airflow channel is provided at the center of the grinding wheel, and a hollow chamber is fixedly installed on the side of the grinding wheel away from the metal umbrella plate. The hollow chamber is connected to the airflow channel, and an air jet pipe is fixedly installed on the outer surface of the hollow chamber, with the working surface of the air jet pipe facing the grinding wheel. A guide tube is fixedly installed on the metal umbrella plate, with one end of the guide tube penetrating the metal umbrella plate and the other end of the guide tube slidably connected in the airflow channel.

[0013] Preferably, a retaining ring and a support are fixedly installed inside the jet pipe, a slide rod is slidably installed on the support, a baffle is fixedly installed on the side of the slide rod near the retaining ring, and a second spring is sleeved on the slide rod, with the two ends of the second spring being fixedly connected to the support and the baffle, respectively.

[0014] Preferably, the frame is provided with a sliding groove, the recycling bin is fixedly installed with a slider, the slider is connected in the sliding groove, and cylinders are rotatably installed on both sides of the frame, the movable end of the cylinder is rotatably connected to the outer wall of the recycling bin.

[0015] Preferably, the recycling bin has an insert plate at one end near the receiving bin, and a flexible belt is fixedly installed on the inner wall of the opening of the receiving bin. When the recycling bin is inserted into the receiving bin, the insert plate and the flexible belt form a lip seal structure.

[0016] Preferably, the quantitative feeding device further includes a feeding belt located on one side of the frame, and an industrial vision system is arranged on the side of the feeding belt; the industrial vision system includes an image acquisition device and an image processing unit, configured to acquire real-time images of the plastic raw materials conveyed by the feeding belt, and identify material color abnormalities or foreign matter mixing based on a preset algorithm, and output feedback signals to the control unit to adjust the conveying parameters of the feeding belt.

[0017] Compared with the prior art, the beneficial effects of the present invention are: 1. Through the mechanical linkage design between the airbag dual-chamber structure, the metal umbrella plate, the crushing device, and the receiving box, a collaborative working mechanism of edge pressure stabilization and sealing and central pulsating unloading is achieved. When the first air chamber is inflated to form a stable annular support to seal the dust, the second air chamber periodically expands and contracts, pushing the metal umbrella plate to move locally upward, triggering quantitative discharge. At the same time, the metal umbrella plate returns to its original position under its own weight and compresses the second air chamber, so that the gas in the second air chamber enters the rotating airflow channel through the guide tube on the metal umbrella plate, and then flows into the hollow chamber. It is then ejected at high speed through the jet pipe, directly blowing the grinding interface between the grinding wheel and the grinding block, timely blowing the fine particles that have been ground to the standard away from the grinding area, preventing over-crushing, and carrying away the heat generated by friction to avoid plastic melting and adhesion. The airflow also guides the material to concentrate in the center of the receiving box, improving the discharge efficiency.

[0018] 2. Through the guide cooperation of the slide-slider and the double-sided cylinder drive structure, combined with the lip seal formed by the bottom plate of the recycling box and the flexible belt inside the receiving box, automatic centering and dynamic sealing are achieved during the vertical lifting of the recycling box. This structure not only ensures smooth lifting without swaying, but also forms a reliable sealing interface at the moment of insertion into the receiving box, effectively suppressing the escape of dust during the discharge stage after crushing, and improving the safety of the working environment and the convenience of equipment maintenance. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the internal structure of the recycling bin of the present invention; Figure 3 This is a schematic diagram of the crushing device of the present invention; Figure 4 This is a schematic diagram of the grinding wheel structure of the present invention. Figure 5 for Figure 4 Enlarged view of the A-structure; Figure 6 This is a schematic diagram of the receiving box structure of the present invention; Figure 7 This is a schematic diagram of the airbag and metal umbrella plate assembly structure of the present invention; Figure 8 This is a schematic diagram of the airbag structure of the present invention.

[0020] The attached diagram lists the components represented by each number as follows: 10. Frame; 11. Slide groove; 12. Cylinder; 23. Grinding block; 231. Arc-shaped grinding chamber; 20. Recycling bin; 21. Sliding block; 22. Insert plate; 30. Crushing device; 31. Metal umbrella plate; 311. Guide tube; 32. Bushing; 33. Blade; 34. Servo motor; 35. Central shaft; 351. Damping pad; 352. Spring one; 36. Grinding wheel; 361. Airflow channel; 362. Hollow chamber; 363. Jet pipe; 37. Knob; 301. Retaining ring; 302. Support; 303. Slide rod; 304. Baffle; 305. Spring two; 40. Receiving box; 41. Hollow frame; 42. Airbag; 421. First air chamber; 422. Second air chamber; 43. Flexible belt; 50. Feeding belt; 60. Industrial vision systems. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] Example 1: Refer to Figure 1 - Figure 8 The figure shows a quantitative feeding device for plastic production, which is mainly used for the recycling of plastic waste and is suitable for the front-end feeding process such as injection molding and extrusion.

[0023] It includes a frame 10, a recycling bin 20, a crushing device 30, and a receiving bin 40.

[0024] The frame 10 is an integral support structure, welded from structural steel, possessing sufficient rigidity and stability. A recycling bin 20 is mounted on the frame 10, containing a crushing device 30 to crush large pieces of plastic into particle sizes suitable for subsequent processing. A receiving bin 40 is also included, placed on the frame 10, and is separately positioned from the frame 10 and recycling bin 20 for easy disassembly, cleaning, or replacement, while preventing vibration transmission from affecting weighing or measurement accuracy. A metal umbrella-shaped plate 31 is slidably mounted on one end of the crushing device 30 near the receiving bin 40. The structure features a metal umbrella panel 31 in contact with the inner wall of the recycling bin 20, effectively preventing material leakage through gaps. A perforated frame 41 is installed inside the receiving bin 40. This perforated frame 41 is composed of multiple cross support rods, which have sufficient load-bearing capacity and do not affect the passage of materials. An airbag 42 is fixedly installed on the perforated frame 41. The airbag 42 is connected to an air source and can be controlled to inflate or deflate. Crucially, the outer contour of the airbag 42 is adapted to the inner surface contour of the metal umbrella panel 31, that is, the two are geometrically matched and can abut against the inner surface of the metal umbrella panel 31 to form a closed chamber.

[0025] Waste plastic raw materials are put into the recycling bin 20. The crushing device 30 is started to shear, crush, or impact the material to achieve the target particle size. The plastic particles of the target particle size formed after crushing fall onto the upper surface of the metal umbrella plate 31 under the action of gravity. The metal umbrella plate 31 is shaped like an inverted bowl and can move up and down in the vertical direction. Under normal conditions, it is held at the lower limit position by its own weight, forming a stable material receiving platform. When feeding in a quantitative manner, an external air source supplies air to the air bag 42. The air bag 42 is rapidly inflated and expanded. Its top curved surface is adapted to the inner surface contour of the metal umbrella plate 31. The metal umbrella plate 31 is pushed upwards to overcome its own weight and move upwards. As the metal umbrella plate 31 moves upwards, the line-to-surface contact between it and the inner wall of the recycling bin 20 is released, forming a discharge channel in the central area. At the same time, due to the tilt angle of the metal umbrella plate 31, the plastic particles accumulated on it fall down under the action of gravity and into the receiving bin 40 below, completing one quantitative discharge. After the discharge is completed, the air source is turned off, and the metal umbrella plate 31 returns to its original position under its own weight and compresses the air bag 42 to re-form the material receiving surface, waiting for the next batch of crushed material to enter the next working cycle.

[0026] Reference Figure 8 In this embodiment, the airbag 42 is a composite dual-cavity structure. The airbag 42 has a first air chamber 421 and a second air chamber 422 that are isolated from each other. The two air chambers are completely independent in terms of physical space and air passage and are not connected to each other.

[0027] The first air chamber 421 is arranged along the circumferential edge of the airbag 42. Its cross-section can be rectangular, arc-shaped, or trapezoidal. It surrounds the outer edge area of ​​the airbag 42 and is connected to the first air source through the first air intake pipe. The first air source inflates the first air chamber 421, causing it to expand and maintain a preset pressure, thereby forming a rigid annular support platform for tightly abutting against the inner surface contour of the upper metal umbrella plate 31 to achieve edge sealing and support functions. The second air chamber 422 is located in the central area of ​​the airbag 42 and has a circular protruding structure. It is connected to the second air source through the second air intake pipe. Crucially, the first air intake pipe is equipped with a normally closed solenoid valve, and the outlet ends of the second air intake pipe and the second air chamber 422 are both equipped with one-way valves. The working surfaces of the one-way valves on both sides are opposite.

[0028] The inlet check valve allows gas to flow into the second chamber 422 from the second gas source in one direction, preventing reverse leakage; the outlet check valve allows gas to flow out of the second chamber 422 to the outlet in one direction.

[0029] By using the reverse configuration of the above-mentioned dual one-way valves, in conjunction with the intermittent air supply control of the second air source, the periodic inflation, pressure holding, exhaust, and retraction actions of the second air chamber 422 can be realized.

[0030] When the second gas source supplies gas, the gas overcomes the opening pressure of the inlet one-way valve and enters the second gas chamber 422, causing it to expand rapidly and push upwards to the central area of ​​the metal umbrella plate 31, causing the metal umbrella plate 31 to move upwards and trigger unloading. After the gas supply stops, the metal umbrella plate 31 returns to its original position under its own weight and compresses the second gas chamber 422, causing the second gas chamber 422 to contract until the next working cycle begins.

[0031] Reference Figure 2 and Figure 3 The crushing device 30 includes a bushing 32 rotatably installed inside the recycling bin 20. The bushing 32 is rotatably installed inside the recycling bin 20 via a bearing bracket, and its axis extends vertically. A blade 33 is fixedly installed on the bushing 32 for preliminary shearing and crushing of the waste plastics put into the recycling bin 20. A servo motor 34 is fixedly installed on the outer wall of the recycling bin 20. The output end of the servo motor 34 is connected to the bushing 32 via a belt drive, thereby driving the bushing 32 and the blade 33 to rotate at high speed, achieving efficient crushing of materials.

[0032] Furthermore, the crushing device 30 also includes a central shaft 35, which is coaxially inserted inside the bushing 32. One end of the central shaft 35 near the metal umbrella plate 31 extends out of the bushing 32 and is fixedly mounted with a grinding wheel 36. A damping pad 351 is fitted on the central shaft 35 and is sandwiched between the bushing 32 and the central shaft 35 to provide axial damping force and suppress axial movement caused by impact load during the grinding process.

[0033] Furthermore, the central shaft 35 is threadedly engaged with the bushing 32, and the other end of the central shaft 35 also extends through the bushing 32 and is fixedly mounted with a knob 37. A grinding block 23 is fixedly installed inside the receiving box 40. The grinding block 23 has an arc-shaped grinding cavity 231 in the center. The grinding wheel 36 is collinear with the center of the arc-shaped grinding cavity 231, so that the grinding wheel 36 can rotate and crush in the arc-shaped grinding cavity 231 to perform secondary fine grinding on the initially crushed plastic particles, ensuring that the output particle size is uniform. A spring 352 is sleeved on the central shaft 35. The two ends of the spring 352 abut against the bushing 32 and the grinding wheel 36 respectively, and work together with the damping pad 351. The spring 352 provides preload force to ensure that the grinding wheel 36 always fits against the arc-shaped grinding cavity 231. At the same time, when encountering hard foreign objects, the grinding wheel 36 is allowed to move upward briefly, which plays an overload protection role and avoids equipment damage.

[0034] During operation, the servo motor 34 drives the bushing 32 and the blade 33 to rotate, completing the primary crushing. At the same time, the grinding wheel 36 rotates together with the central shaft 35. Because it is threadedly connected to the bushing 32 and limited by the knob 37, it grinds the material in the arc-shaped grinding chamber 231. The grinding gap can be manually fine-tuned by the knob 37. The damping pad 351 and the spring 352 together ensure the stability and safety of the grinding system.

[0035] Reference Figure 4 and Figure 5 The grinding wheel 36 has a hollow structure with an airflow channel 361 at its center, which runs through both the upper and lower ends of the grinding wheel 36. A hollow chamber 362 is fixedly installed on the upper surface of the grinding wheel 36, away from the metal umbrella plate 31. The hollow chamber 362 communicates with the airflow channel 361, forming a continuous gas flow path. A jet pipe 363 is fixedly installed on the outer surface of the hollow chamber 362, with its working surface facing the grinding wheel 36. This jet pipe 363 is used to directionally inject compressed air into the gap between the grinding wheel 36 and the arc-shaped grinding chamber 231, achieving material purging, dust suppression, and... Cooling function; Correspondingly, a guide tube 311 is fixedly installed on the metal umbrella plate 31. The guide tube 311 is a hollow tubular structure. One end of the guide tube 311 passes through the metal umbrella plate 31, and the other end of the guide tube 311 is slidably connected in the airflow channel 361, forming a sliding sealing pair that can move relatively axially but maintains an airtight connection. In this way, when the grinding wheel 36 rotates with the central shaft 35, the guide tube 311 remains stationary, while the airflow channel 361 rotates synchronously. The two are connected by sliding cooperation to achieve rotational air supply, ensuring that compressed air is continuously and stably input into the hollow chamber 362.

[0036] Furthermore, to prevent airflow turbulence or backflow caused by back pressure fluctuations during jet injection, the jet pipe 363 is equipped with a self-adjusting throttling mechanism. Specifically, a baffle ring 301 and a support 302 are fixedly installed inside the jet pipe 363. A slide rod 303 is slidably installed on the support 302. A baffle 304 is fixedly installed on the side of the slide rod 303 near the baffle ring 301. A second spring 305 is sleeved on the slide rod 303. The two ends of the second spring 305 are fixedly connected to the support 302 and the baffle 304, respectively.

[0037] It should be noted that the outer diameter of the baffle 304 is smaller than the inner diameter of the jet pipe 363, allowing it to move within a certain stroke to adjust the flow cross-sectional area. Under normal conditions, spring 305 pushes the baffle 304 towards the retaining ring 301, maintaining a small gap between them to form an initial throttling orifice. When the air pressure inside the hollow chamber 362 increases, the airflow pushes the baffle 304 backward against the elastic force of spring 305, increasing the flow area. When the air pressure decreases, spring 305 returns to its original position, reducing the opening. This achieves automatic pressure stabilization and anti-clogging regulation of the airflow.

[0038] The metal umbrella plate 31 returns to its original position under its own weight and compresses the second air chamber 422, causing the gas in the second air chamber 422 to enter the rotating airflow channel 361 through the guide tube 311 on the metal umbrella plate 31, and then flow into the hollow chamber 362. It is then ejected at high speed through the jet pipe 363, directly blowing the grinding interface between the grinding wheel 36 and the grinding block 23. This blows away the fine particles that have been ground to the required standard from the grinding area in time, preventing over-grinding, and carrying away the heat generated by friction to avoid plastic melting and adhesion. The airflow also guides the material to concentrate in the center of the receiving box 40, improving the material feeding efficiency.

[0039] Example 2: A sliding groove 11 is provided on the frame 10. Correspondingly, a slider 21 is fixedly installed on the recycling bin 20. The slider 21 is connected in the sliding groove 11, so that the recycling bin 20 can be raised and lowered smoothly in the vertical direction along the frame 10, while preventing horizontal sway. In order to drive the recycling bin 20 to rise and fall, cylinders 12 are rotatably installed on both sides of the frame 10. Specifically, they are hinged to the base of the frame 10 through pins. The movable end of the cylinder 12 is rotatably connected to the outer wall of the recycling bin 20, forming a dual-side synchronous drive structure. When the cylinder 12 extends or retracts, it can smoothly push or pull back the recycling bin 20 to achieve its precise up and down movement.

[0040] Furthermore, the end of the recycling bin 20 near the receiving bin 40 has an insert plate 22. The insert plate 22 can be an integrally formed flange at the bottom of the recycling bin 20. Its outer edge is smooth and has a certain rigidity. A flexible belt 43 is fixedly installed on the inner wall of the opening of the receiving bin 40. The flexible belt 43 has an L-shaped cross section. One end is firmly fixed to the outer wall of the receiving bin 40 by adhesive bonding, and the other end is freely suspended, facing the downward path of the recycling bin 20. When the recycling bin 20 is inserted into the receiving bin 40, the insert plate 22 and the flexible belt 43 form a lip seal structure.

[0041] As the recycling bin 20 moves downward, the insert plate 22 applies radial pressure to the flexible belt 43, causing its sealing lip to elastically deform and tightly wrap around the outer periphery of the insert plate 22, forming an annular lip seal interface. This effectively blocks the connection between the crushing chamber and the external environment, preventing dust from escaping into the workshop during the discharge process. After the seal is established, the crushing device 30 starts the discharge action, allowing the crushed plastic particles to fall into the receiving box 40 through the sealed cavity, achieving a closed, quantitative, and low-dust-emission feeding process.

[0042] Example 3: The quantitative feeding device also includes a feeding belt 50 located on one side of the frame 10, which is used to continuously transport the pretreated plastic raw materials to the feed port of the recycling box 20. Its drive end is connected to a speed regulating motor to realize the adjustment of the conveying speed. An industrial vision system 60 is provided on the side of the feeding belt 50. The industrial vision system 60 includes an image acquisition device and an image processing unit, which are connected via a data cable or a wireless communication module. The image acquisition device includes an industrial camera, a light source, and a lens assembly, mounted on a bracket. Its field of view covers the stable area of ​​material flow on the feed belt 50, ensuring clear imaging without motion blur. The light source provides uniform illumination to enhance the contrast of material color, texture, and foreign objects. The image processing unit can be an embedded industrial computer, a PLC-integrated vision module, or a cloud edge computing device. It has pre-stored image recognition algorithm models and is configured to perform real-time image acquisition of the plastic raw materials conveyed by the feed belt 50, and identify material color anomalies or foreign object contamination based on a preset algorithm. It then outputs feedback signals to the control unit to adjust the conveying parameters of the feed belt 50.

[0043] During operation, the industrial vision system 60 continuously acquires and analyzes images of the plastic raw materials conveyed by the feed belt 50 in real time, focusing on identifying the following two types of abnormal states: (1) Color abnormality: such as the presence of non-target color masterbatch, degraded color-changing material, residual label fragments, etc.; (2) Foreign matter contamination: such as metal shavings, paper scraps, wood blocks, rubber or other non-plastic impurities.

[0044] Once abnormal material is detected, the image processing unit immediately generates a feedback signal and sends it to the main control unit of the device (not shown), reducing the operating speed of the feed belt 50 so that manual intervention or a downstream rejection mechanism can respond.

[0045] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0046] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A quantitative feeding device for plastic production, comprising a frame (10), characterized in that, A recycling bin (20) is installed on the frame (10), and a crushing device (30) is provided inside the recycling bin (20). It also includes a receiving bin (40), which is placed on the frame (10) and is set separately from the frame (10) and the recycling bin (20). The crushing device (30) has a metal umbrella plate (31) slidably installed at one end near the receiving box (40). The metal umbrella plate (31) is in line-surface contact with the inner wall of the recycling box (20). A hollow frame (41) is installed inside the receiving box (40). An air bag (42) is fixedly installed on the hollow frame (41). An air source is connected to the outside of the air bag (42). The outer contour of the air bag (42) is adapted to the inner surface contour of the metal umbrella plate (31) and can abut against the inner surface of the metal umbrella plate (31) to form a closed chamber.

2. The quantitative feeding device for plastic production according to claim 1, characterized in that: The airbag (42) is provided with a first air chamber (421) and a second air chamber (422) that are isolated from each other. The first air chamber (421) is arranged along the circumferential edge of the airbag (42) and is connected to a first air source through a first air intake pipe. The second air chamber (422) is located in the central area of ​​the airbag (42) and is connected to a second air source through a second air intake pipe. The first intake pipe is equipped with a normally closed solenoid valve, and the second intake pipe and the outlet of the second air chamber (422) are both equipped with one-way valves, with the working surfaces of the one-way valves on both sides being opposite.

3. The quantitative feeding device for plastic production according to claim 1, characterized in that: The crushing device (30) includes a bushing (32) rotatably installed inside the recycling box (20), a blade (33) is fixedly installed on the bushing (32), and a servo motor (34) is fixedly installed on the outer wall of the recycling box (20). The output end of the servo motor (34) is connected to the bushing (32) by belt drive.

4. The quantitative feeding device for plastic production according to claim 1, characterized in that: The crushing device (30) also includes a central shaft (35), one end of which, near the metal umbrella plate (31), passes through a bushing (32) and is fixedly fitted with a grinding wheel (36). The central shaft (35) is fitted with a damping pad (351), which is sandwiched between the bushing (32) and the central shaft (35) to provide axial damping force.

5. A quantitative feeding device for plastic production according to claim 4, characterized in that: The central shaft (35) is threadedly engaged with the bushing (32). The other end of the central shaft (35) also passes through the bushing (32) and is fixedly installed with a knob (37). The receiving box (40) is fixedly installed with a grinding block (23). The grinding block (23) has an arc-shaped grinding cavity (231) in the center. The grinding wheel (36) is collinear with the center of the arc-shaped grinding cavity (231). A spring (352) is fitted on the central shaft (35), and the two ends of the spring (352) abut against the bushing (32) and the grinding wheel (36) respectively.

6. The quantitative feeding device for plastic production according to claim 4, characterized in that: An airflow channel (361) is provided at the center of the grinding wheel (36). A hollow chamber (362) is fixedly installed on the side of the grinding wheel (36) away from the metal umbrella plate (31). The hollow chamber (362) is connected to the airflow channel (361). A jet pipe (363) is fixedly installed on the outer circular surface of the hollow chamber (362). The working surface of the jet pipe (363) faces the grinding wheel (36). A guide tube (311) is fixedly installed on the metal umbrella plate (31). One end of the guide tube (311) passes through the metal umbrella plate (31), and the other end of the guide tube (311) is slidably connected in the airflow channel (361).

7. A quantitative feeding device for plastic production according to claim 6, characterized in that: The jet pipe (363) is fixedly installed with a retaining ring (301) and a support (302). A slide rod (303) is slidably installed on the support (302). A baffle (304) is fixedly installed on the side of the slide rod (303) near the retaining ring (301). A second spring (305) is sleeved on the slide rod (303). The two ends of the second spring (305) are fixedly connected to the support (302) and the baffle (304) respectively.

8. A quantitative feeding device for plastic production according to claim 1, characterized in that: The frame (10) is provided with a slide groove (11), and a slider (21) is fixedly installed on the recycling bin (20). The slider (21) is connected in the slide groove (11). Cylinders (12) are rotatably installed on both sides of the frame (10). The movable end of the cylinder (12) is rotatably connected to the outer wall of the recycling bin (20).

9. A quantitative feeding device for plastic production according to claim 1, characterized in that: The recycling bin (20) has a plate (22) at one end near the receiving bin (40). A flexible belt (43) is fixedly installed on the inner wall of the opening of the receiving bin (40). When the recycling bin (20) moves down and is inserted into the receiving bin (40), the plate (22) and the flexible belt (43) form a lip seal structure.

10. A quantitative feeding device for plastic production according to claim 1, characterized in that: The quantitative feeding device also includes a feeding belt (50) located on one side of the frame (10), and an industrial vision system (60) is provided on the side of the feeding belt (50). The industrial vision system (60) includes an image acquisition device and an image processing unit, configured to acquire real-time images of plastic raw materials conveyed by the feeder belt (50), identify material color abnormalities or foreign matter mixing based on a preset algorithm, and output feedback signals to the control unit to adjust the conveying parameters of the feeder belt (50).

Images