Bottle cap separation pretreatment device for plastic bottle recovery

Abstract

The invention relates to the technical field of plastic recovery treatment, in particular to a plastic bottle recovery bottle cap separation pretreatment device, and the core design idea of the device is to construct an automatic system integrating sensing, decision making and execution. According to the system, a movable recycling trolley serves as a carrier, an automatic visual recognition sensing system serves as a sensing center, three functional modules of a recycling roller set, a steering conveying mechanism and a bottle cap separating mechanism are sequentially connected in series, and finally the recycling trolley and a storage trolley cooperate to complete material collection. Through precise space-time cooperation of the bottle body clamping assembly, the cap screwing assembly, the bottle cap collecting assembly and the bottle body conveying assembly, stable clamping of a bottle body, unscrewing and clamping of a bottle cap, vacuum suction and transfer of the bottle cap, pushing of the bottle body and airflow conveying are sequentially completed, and finally high-purity and high-efficiency physical separation and classified collection of the bottle body and the bottle cap are achieved.

Description

Technical Field

[0001] This invention relates to the field of plastic recycling technology, specifically to a pretreatment device for separating and processing plastic bottle caps. Background Technology

[0002] Plastic packaging products, especially beverage bottles, are consumed in enormous quantities in modern society, and their effective recycling is of great significance for resource recycling and environmental protection. A typical plastic bottle consists of a body and a cap. The body is primarily made of polyethylene terephthalate (PET), while the cap is usually made of polypropylene (PP) or polyethylene (PE). These two plastics differ significantly in their chemical properties, melting point, and recycling value. Mixing them during recycling not only reduces the quality and value of the recycled material but may also cause carbonization during production, clogging the spinnerets and severely affecting the processing performance of subsequent products. Therefore, effective cap separation is a crucial pretreatment step before plastic bottles enter deep processing stages such as crushing, washing, and granulation.

[0003] Currently, pretreatment methods for separating bottle caps have the following limitations:

[0004] Manual sorting and separation relies on operators manually picking up plastic bottles and unscrewing the caps. This method is labor-intensive, inefficient, has high labor costs, and provides a poor working environment, making it difficult to achieve large-scale, continuous operations.

[0005] Centralized crushing followed by sorting: Some recycling lines directly crush the whole bottle and then use methods such as wind separation or hydraulic flotation to separate plastic fragments of different densities. However, this method has problems such as high energy consumption, unsatisfactory separation purity (easy to mix), and difficulty in completely removing impurities such as rubber gaskets inside the bottle cap. At the same time, the crushing process also increases the risk of material contamination.

[0006] Semi-automated mechanical separation: Most existing automated separation equipment is designed for fixed production lines, requiring plastic bottles to enter the equipment in a specific posture and sequence. They exhibit extremely poor adaptability to plastic bottles scattered in open environments (such as parks, streets, and garbage transfer stations), with varying postures and even residual liquid. These devices cannot autonomously complete the front-end process of "identification-pickup-feeding," resulting in a low degree of automation.

[0007] In conclusion, developing an intelligent, integrated pretreatment device that can proactively adapt to complex environments and autonomously complete the entire process from recycling to separation has become a key technological bottleneck in improving the efficiency and quality of plastic bottle recycling. Summary of the Invention

[0008] To solve the above technical problems.

[0009] This application provides a pre-treatment device for separating bottle caps during plastic bottle recycling. Its core design concept lies in constructing an automated system integrating perception, decision-making, and execution. The system uses a mobile recycling trolley as its carrier, a visual automatic recognition sensing system as its sensing center, and sequentially connects three functional modules: a recycling roller assembly, a steering conveyor mechanism, and a bottle cap separation mechanism. Ultimately, it collaborates with the collection trolley to complete material collection.

[0010] The visual automatic recognition sensing system, acting as the "eyes" of the device, is responsible for scanning the work area in real time, accurately locating the spatial coordinates of scattered plastic bottles, and intelligently identifying key information such as the orientation of the bottle opening and the bottle's posture. The recycling roller assembly, acting as a "robotic arm," simulates human hand picking actions through the combined movements of its unique swing arm, rotating frame, and multiple turning and conveying rollers, based on instructions from the vision system. It can reliably pick up scattered plastic bottles at different positions and angles and send them to the next process. The steering and conveying mechanism, acting as a "posture calibration unit," again utilizes visual information for feedback control. Through the differential motion generated by the symmetrically arranged conveying roller assembly, or the intervention of an auxiliary steering rod, it adjusts the posture of the moving plastic bottles online, ensuring that all plastic bottles are conveyed to the core workstation with the correct posture and uniform bottle opening orientation. As the "execution terminal," the bottle cap separation mechanism, through the precise spatiotemporal coordination of the bottle body clamping component, the cap screwing component, the cap collecting component, and the bottle body conveying component, sequentially completes the stable clamping of the bottle body, the loosening and clamping of the cap, the vacuum suction and transfer of the cap, and the pushing and airflow conveying of the bottle body, ultimately achieving high-purity and high-efficiency physical separation and classified collection of the bottle body and the cap.

[0011] A plastic bottle recycling cap separation pretreatment device includes a plastic bottle recycling trolley based on a vision automatic recognition sensing system, comprising: a recycling roller assembly, a steering conveying mechanism, and a cap separation mechanism. The recycling roller assembly, steering conveying mechanism, and cap separation mechanism are all installed on the recycling trolley. The recycling roller assembly includes two first rotating rollers, one second rotating roller, and a rotary conveying roller. The two first rotating rollers are connected by a rotating frame, and the second rotating roller and the rotary conveying roller are rotatably connected by a swing arm. The swing arm is installed at one end of the recycling trolley via a support frame, and the rotating frame is rotatably installed in the middle of the swing arm. Each rotating roller and the rotary conveying roller is driven by a synchronous belt pulley drive module. The rotating frame and the swing arm are connected by a gear transmission and driven by a synchronous belt pulley drive module to realize the opening and closing of the rotating frame and the swing arm. The swing arm is driven by a sprocket transmission module to realize the swinging of the swing arm. By controlling the rotation of the swing arm to adjust the position of the rotary conveying rollers on the rotating frame and at the lower end of the swing arm, when the recycling trolley moves to the location of the plastic bottle, the plastic bottle is conveyed to the turning conveying mechanism through the cooperation of the first turning roller on the rotating frame and the rotary conveying roller on the swing arm, as well as the opening and closing of the rotating frame and the swing arm.

[0012] Furthermore, the steering and conveying mechanism includes two symmetrically arranged conveying roller sets and an auxiliary steering rod. The conveying roller sets include a steering roller, a shifting roller, and two conveying rollers. The steering roller, shifting roller, and two conveying rollers are all driven to rotate by a synchronous belt drive module. The posture of the plastic bottle is identified by a visual automatic recognition sensor system. The different rotation directions of the two symmetrically arranged steering rollers are used to adjust the orientation of the bottle opening so that the bottle opening faces the cap separation mechanism. The auxiliary steering rod is rotatably arranged between the conveying roller sets and is driven to rotate by a drive motor.

[0013] Furthermore, the bottle cap separation mechanism includes a cap screwing assembly, a bottle body clamping assembly, a bottle body conveying assembly, and a bottle cap collecting assembly. The cap screwing assembly is set on one side of the bottle body clamping assembly, the bottle body conveying assembly, and the bottle cap collecting assembly via a movable module. The bottle body clamping assembly, the bottle body conveying assembly, and the bottle cap collecting assembly are all mounted on the recycling trolley via mounting plates and face the conveying roller assembly. The bottle body clamping assembly and the bottle cap collecting assembly are slidably mounted on the mounting plate via slides and slide rails.

[0014] Furthermore, the bottle clamping assembly includes two sets of clamping arc plates and clamping seats. Each set of clamping arc plates is symmetrically mounted on the upper and lower ends of the clamping seat via a set of figure-eight inclined rails. The clamping seat is fixedly mounted on the slide table. Each set of clamping arc plates is pushed by a corresponding actuator to slide on the figure-eight inclined rails, so that the upper and lower sets of clamping arc plates can move closer to each other for clamping or move away from each other for release.

[0015] Furthermore, the bottle cap collecting assembly includes a collecting hopper and a cap-retrieving module. Both the collecting hopper and the cap-retrieving module are mounted on a slide table via a collecting frame. The collecting hopper is located below the cap-retrieving module and is fixed to the collecting frame via a hopper base. A hopper gate is slidably mounted on the hopper base, and a return spring is connected to one side of the hopper gate. In the initial position, the collecting hopper faces the bottle cap conveying pipe below, which is mounted on a collection trolley. In the initial state, the hopper gate abuts against the bottle cap conveying pipe, causing the hopper gate to be pushed to one side. At this time, the bottle cap conveying pipe below the collecting hopper is connected, and bottle caps fall from the collecting hopper into the bottle cap conveying pipe. A blower head installed at one end of the bottle cap conveying pipe blows the bottle caps into the collection trolley. When the bottle cap collecting assembly is moved to the cap-screwing assembly to collect bottle caps, the hopper gate resets and closes the lower outlet of the collecting hopper under the action of the return spring.

[0016] Furthermore, the cap-retrieving module includes a suction cup, a retrieving push rod, and a fixed base. The suction cup is mounted on the fixed base via a guide rod assembly and a rotating plate. The retrieving push rod pushes the suction cup to extend and retract so that it approaches the gripper of the cap-screwing assembly. One end of the rotating plate is hinged to the fixed base. The rotating plate is driven to rotate around the hinge point by the rotating push rod. During cap retrieval, the rotating push rod pushes the rotating plate to rotate, making it and the suction cup horizontal. Then, the retrieving push rod pushes the suction cup to extend and grip the cap held by the cap-screwing assembly. Then, the retrieving push rod and the suction cup grip the cap tightly and reset it. Then, the rotating push rod rotates the rotating plate, the suction cup, and the cap downwards to a vertical position. The suction cup releases the cap, and the cap falls into the retrieval hopper. After the cap retrieval assembly completes the cap retrieval, the push rod pushes the slide to reset back to its initial position. When the retrieval hopper approaches the cap delivery pipe below, the top of the cap delivery pipe abuts against the hopper gate, causing the hopper gate to open and the cap to fall into the cap delivery pipe.

[0017] Furthermore, the bottle conveying assembly includes a bottle push rod and two blowing heads. The bottle push rod faces the bottle conveying pipe, which is installed on the recycling trolley. Both blowing heads are installed on the bottle push rod. When the bottle clamping assembly moves the bottle to the bottle conveying pipe, the bottle push rod extends to push the bottle into the bottle conveying pipe, and then the blowing heads blow the bottle into the collection trolley.

[0018] The beneficial effects of this invention compared to the prior art are:

[0019] 1. This application is the first to deeply integrate a mobile platform, machine vision, and multiple specialized mechanical actuators, achieving fully unmanned operation from "environmental perception - target acquisition - online posture adjustment - precision separation - classification and collection." This completely changes the traditional model that relies on manual labor or fixed production lines, and is a key piece of equipment for future smart cities and unmanned sanitation systems.

[0020] 2. This device can operate continuously without interruption, and its processing efficiency is far higher than that of manual sorting. According to the estimation model, a single device can process hundreds of plastic bottles per hour, which greatly reduces labor and time costs, increases recycling output per unit time, and has significant economic benefits.

[0021] 3. The adaptive opening, closing, and oscillating design of the recycling rollers enables them to effectively grasp scattered bottles that are laid flat, leaning, or even partially stacked, demonstrating strong adaptability to complex ground environments. The entire device is integrated onto a mobile cart and can be flexibly deployed to various scenarios such as parks, squares, campuses, and communities according to task requirements, breaking through the spatial limitations of fixed equipment.

[0022] 4. Employing whole-bottle non-destructive separation technology avoids cross-contamination and material degradation that may result from crushing and sorting. The separated bottle body and cap have high purity, greatly improving the grade and market value of recycled plastics and laying a solid foundation for subsequent high-value recycling. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the three-dimensional structure of the present invention. Figure 1 ;

[0024] Figure 2 This is a schematic diagram of the three-dimensional structure of the present invention. Figure 2 ;

[0025] Figure 3 This is a three-dimensional structural diagram of the recycling roller assembly of the present invention;

[0026] Figure 4 This is a three-dimensional structural schematic diagram of the steering and conveying mechanism of the present invention;

[0027] Figure 5 This is a three-dimensional structural diagram of the bottle cap separation mechanism of the present invention. Figure 1 ;

[0028] Figure 6 This is a three-dimensional structural diagram of the bottle cap separation mechanism of the present invention. Figure 2 ;

[0029] Figure 7 This is a three-dimensional structural diagram of the bottle cap separation mechanism of the present invention. Figure 3 ;

[0030] Figure 8 for Figure 7 Enlarged view of point A in the middle;

[0031] 1. Recycling trolley; 11. Bottle body conveying pipe; 12. Bottle cap conveying pipe; 2. Recycling roller assembly; 21. Support frame; 22. Swing arm; 23. Rotating frame; 24. First turning roller; 25. Second turning roller; 26. Rotating roller; 27. Synchronous belt pulley drive module one; 28. Sprocket drive module; 3. Steering conveying mechanism; 31. Conveying roller assembly; 311. Steering roller; 312. Turning roller; 313. Conveying roller; 32. Auxiliary steering rod; 33. Synchronous belt drive module two; 4. Bottle cap separation mechanism; 41. Mounting plate; 42. Bottle body clamping assembly; 421. Slide table; 422. Clamping seat; 423. Clamping arc plate; 424. Figure-eight inclined rail; 425. Actuator; 43. Bottle cap collecting assembly; 431. Collecting rack; 433. Collecting hopper; 434. Cap taking module; 4341. Fixing seat; 4342. Suction cup; 4343. Collecting push rod; 4344. Rotating plate; 4345. Rotating push rod; 435. Hopper seat; 436. Hopper gate; 437. Return spring; 44. Bottle body conveying assembly; 441. Bottle body push rod; 442. Blowing head; 45. Cap screwing assembly; 451. Moving module. Detailed Implementation

[0032] The following description is intended to disclose the invention and enable those skilled in the art to implement it. The preferred embodiments described below are merely examples, and other obvious variations will occur to those skilled in the art.

[0033] like Figure 1 and 2 As shown, the main hardware of this device is integrated into an autonomous mobile recycling cart 1. A visual automatic recognition sensing system (typically a combination of an industrial camera and a supplementary light) is installed at the front or top of the cart body to globally perceive target plastic bottles within the working area.

[0034] Recycling and Orientation Process: The recycling trolley 1 travels to the target work area according to a preset path or central dispatch. After the vision system identifies the scattered plastic bottles, it sends the position and orientation information to the main controller. The controller then instructs the recycling roller assembly 2 to move. The sprocket drive module first drives the swing arm 22 to swing as a whole, making it roughly aligned with the target area. Subsequently, the synchronous belt pulley drive module 27 starts, driving all the turning rollers (24, 25) and the rotary conveyor roller 26 to rotate via the synchronous belt, and driving the rotating frame 23 to generate a tensioning motion relative to the swing arm 22 via the gear set. The rotation of these rollers is coupled with the tensioning and swinging of the mechanism to form a dynamic "collection net" that can lift the plastic bottles from the ground and steadily send them into the steering conveyor mechanism 3.

[0035] After the plastic bottle enters the steering conveyor mechanism 3, the vision system quickly identifies the orientation of its bottle opening. Based on the identification result, the controller controls the steering rollers 311 in the two symmetrically arranged conveyor roller groups 31 to generate a specific speed difference. This difference in frictional torque drives the plastic bottle to rotate automatically during conveying until its opening faces the bottle cap separation mechanism 4. For a few bottles whose posture is difficult to adjust through differential friction (such as those that are too light or irregularly shaped), the auxiliary steering rod 32 located between the roller groups is activated. Driven by an independent drive motor, it rotates to directly intervene in and correct the bottle's orientation, ensuring that all plastic bottles enter the subsequent separation station with a uniform and correct posture.

[0036] like Figures 3 to 7 As shown, the separation and collection process: After attitude correction, the plastic bottle is smoothly conveyed to the predetermined position of the bottle clamping assembly 42. The controller issues a command, and two actuators 425 (such as cylinders or electric push rods) act simultaneously, driving the upper and lower sets of clamping arc plates 423 to slide towards each other along the figure-eight inclined rail 424. This figure-eight rail design ensures that the clamping arc plates 423 generate a centripetal closing force when approaching the bottle body, thereby reliably holding the bottle body from both the upper and lower positions, while avoiding irregular areas at the bottle mouth and bottom, ensuring clamping stability and centering.

[0037] After the bottle is securely clamped, the capping assembly 45, driven by the moving module 451 (such as a linear module), precisely approaches the bottle opening. The gripper at the front end of the capping assembly 45 (not detailed in the figure) closes, clamping the cap. Subsequently, the gripper rotates under the drive of a rotary drive device (such as a servo motor), unscrewing the cap off the bottle.

[0038] After the capping action is completed, the device enters the material transfer stage. The slide table 421 moves the entire bottle clamping assembly 42 and the bottle it firmly clamps laterally along the slide rail, accurately transferring it to the front of the bottle conveying assembly 44. At the same time, the slide table 421 moves the cap collecting assembly 43 laterally, so that its cap picking module 434 is precisely positioned under the grippers of the capping assembly 45, ready to receive the caps that have been unscrewed.

[0039] like Figure 8As shown, the cap-retrieving module 434 begins the retrieval process: First, the push rod 4345 rotates, pushing the rotating plate 4344 to rotate around its hinge point to a horizontal position. Then, the retrieval push rod 4343 pushes the suction cup 4342 forward until it contacts the cap held by the capping assembly 45. At this point, the vacuum generator (not shown) activates, and the suction cup 4342 firmly holds the cap. Next, the retrieval push rod 4343 retracts, removing the cap from the capping assembly's grippers. Then, the push rod 4345 rotates again, driving the rotating plate 4344 downwards to a near-vertical position. At this point, the suction cup 4342 releases the vacuum, and the cap falls off under gravity, landing precisely in the retrieval hopper 433 below.

[0040] As the bottle cap collecting assembly 43 returns to its initial position along with the slide table 421, the hopper gate 436 at the lower end of the collecting hopper 433 is pushed open by its structure when it approaches the top of the fixed bottle cap conveying pipe 12. This overcomes the force of the return spring 437 and slides open, allowing the bottle caps temporarily stored in the collecting hopper 433 to fall smoothly into the bottle cap conveying pipe 12. The end of the bottle cap conveying pipe 12 is equipped with a pneumatic blowing head, which uses compressed air to blow the bottle caps into the corresponding compartment of the accompanying collecting trolley.

[0041] At the same time, the bottle conveying assembly 44 on the other side begins to operate. The bottle pusher 441 extends, and its front pusher plate (not shown in the figure) acts on the bottom of the bottle being transferred there, smoothly pushing the bottle into the bottle conveying tube 11. The blowing head 442 mounted on the bottle pusher 441 simultaneously sprays a high-speed airflow to assist and blow the bottle through the bottle conveying tube 11, and finally into another independent compartment of the storage cart, realizing the physical separation and classified collection of the bottle body and the bottle cap.

[0042] This completes one work cycle. The bottle clamping assembly 42 releases the bottle, and all moving parts (slide 421, capping assembly 45, bottle push rod 441, etc.) return to their initial state, ready to process the next plastic bottle.

[0043] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention. The scope of protection claimed by the appended claims and their equivalents is defined.

Claims

1. A plastic bottle recycling cap separation pretreatment device, comprising a plastic bottle recycling trolley (1) based on a vision automatic recognition sensing system, characterized in that, Also includes: The recycling roller assembly (2) is installed at the front end of the recycling trolley (1) and is used to pick up scattered plastic bottles; The steering conveyor (3) is installed on the recycling trolley (1) and located behind the recycling roller group (2) to receive and adjust the posture of the plastic bottles; The bottle cap separation mechanism (4) is installed on the recycling trolley (1) and located at the discharge end of the turning conveyor mechanism (3) to separate the bottle body and the bottle cap of the plastic bottle. The recycling roller group (2), the steering conveying mechanism (3) and the bottle cap separation mechanism (4) are all electrically connected to the visual automatic recognition sensing system.

2. The plastic bottle cap separation and pretreatment device according to claim 1, characterized in that, The recovery roller assembly (2) includes a support frame (21), a swing arm (22), a rotating frame (23), two first rotating rollers (24), a second rotating roller (25), and a rotary conveying roller (26). The swing arm (22) is rotatably connected to the support frame (21) through a sprocket drive module, and the rotating frame (23) is rotatably connected to the middle of the swing arm (22) through a gear set; Two first rotating rollers (24) are mounted on the rotating frame (23), and the second rotating roller (25) and the rotary conveying roller (26) are mounted on the lower end of the swing arm (22); The first rotary roller (24), the second rotary roller (25) and the rotary conveyor roller (26) are driven by the synchronous belt pulley drive module (27); The gear set is driven by a synchronous belt pulley drive module (27) to control the opening and closing action between the rotating frame (23) and the swing arm (22).

3. The plastic bottle cap separation and pretreatment device according to claim 1, characterized in that, The steering conveying mechanism (3) includes two symmetrically arranged conveying roller groups (31) and an auxiliary steering rod (32). Each of the conveyor roller groups (31) includes a steering roller (311), a shifting roller (312) and two conveyor rollers (313), all of which are driven by a synchronous belt drive module two (33); The auxiliary steering rod (32) is rotatably positioned between the two conveying roller groups (31) and is driven by an independent drive motor.

4. The plastic bottle cap separation and pretreatment device according to claim 1, characterized in that, The bottle cap separation mechanism (4) includes: Mounting plate (41) is fixed to the recycling trolley (1); The bottle body clamping assembly (42) and the bottle cap collecting assembly (43) are both slidably mounted on the mounting plate (41) via a slide table (421) and a slide rail; the bottle cap collecting assembly (43) is located on one side of the bottle body clamping assembly (42); The bottle body conveying assembly (44) is fixedly installed on the mounting plate (41) and located on the other side of the bottle body clamping assembly (42); The cap screwing assembly (45) is positioned above the bottle clamping assembly (42) via a moving module (451).

5. The plastic bottle cap separation and pretreatment device according to claim 4, characterized in that, The bottle clamping assembly (42) includes a clamping seat (422) and two sets of clamping arc plates (423); The clamping seat (422) is fixed on the slide table (421); The two sets of clamping arc plates (423) are symmetrically slidably installed at the upper and lower ends of the clamping seat (422) via a set of figure-eight inclined rails (424); Each set of clamping arc plates (423) is connected to an actuator (425) for driving it to slide along the figure-eight inclined rail (424) to achieve clamping or releasing.

6. The plastic bottle cap separation and pretreatment device according to claim 4, characterized in that, The bottle cap collecting assembly (43) includes a collecting rack (432), a collecting hopper (433), and a cap taking module (434). The collection rack (432) is fixed on the slide table (421); The collecting hopper (433) is fixed to the collecting frame (432) by the hopper base (435), and the hopper gate (436) is slidably installed on the hopper base (435). The hopper gate (436) is connected to a return spring (437).

7. The plastic bottle cap separation and pretreatment device according to claim 5, characterized in that, The cap removal module (434) includes a fixed base (4341) fixed on the collection frame (432), a suction cup (4342) mounted on the fixed base (4341) via a guide rod assembly, a collection push rod (4343) for pushing the suction cup (4342) to extend and retract, a rotating plate (4344) with one end hinged to the fixed base (4341), and a rotating push rod (4345) for driving the rotating plate (4344) to rotate; the suction cup (4342) is mounted on the rotating plate (4344).

8. The plastic bottle recycling cap separation pretreatment device according to claim 4, characterized in that, The bottle conveying assembly (44) includes a bottle push rod (441) and at least one blowing head (442), the blowing head (442) being mounted on the bottle push rod (441); the recycling trolley (1) is equipped with a bottle conveying pipe (11) facing the bottle push rod (441) and a bottle cap conveying pipe (12) facing the collection hopper (433).

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