A carbon head delivery jet cleaning system

Abstract

The application discloses a carbon head conveying and jet cleaning system and belongs to the technical field of silicon rod recycling and cleaning equipment. The conveying mechanism comprises a quartz chain plate, a vertical plate is arranged on the upstream of the quartz chain plate, the silicon rod can be horizontally conveyed when the vertical plate moves upwards, and the silicon rod on the left side can be blocked when the vertical plate moves downwards. At this time, the quartz chain plate drives the silicon rod on the right side to move rightwards so as to separate the adjacent silicon rods by a distance, and the silicon rods are conveniently picked up one by one. The inert gas which is pre-cooled to a high degree is used for jet cleaning, the high-speed impact capacity is possessed, and the active cooling of the inner wall of the silicon rod mounting hole is simultaneously realized in the cleaning process. Compared with the bombardment mode which only depends on the high-speed airflow at normal temperature or high temperature in the prior art, the local temperature rise caused by friction is effectively inhibited, the thermal oxidation or micro-cracks of the silicon surface do not occur in the cleaning process, and the structural integrity and surface cleanliness of the high-purity silicon material are obviously improved.

Description

Technical Field

[0001] This invention belongs to the technical field of silicon rod recycling and cleaning equipment, specifically relating to a carbon head conveying and spraying cleaning system. Background Technology

[0002] In the polycrystalline silicon production process, to ensure the silicon rod is fixed and conductive within the reduction furnace, a tapered mounting hole is typically pre-drilled at the bottom of the silicon rod, into which a high-purity graphite or carbon "carbon head" is inserted as a connector. After production, the carbon head needs to be removed from the silicon rod. However, due to the high-temperature reaction and mechanical interlocking, the carbon head often adheres firmly to the inner wall of the mounting hole, leaving behind a large amount of free carbon, silicon carbide (SiC), and oxide contamination layers. If these contaminants are not removed, they will severely affect the purity of the silicon rod when it is remelted in the furnace. Especially for semiconductor-grade zone-melted (FZ) silicon, even trace amounts of metal or carbon impurities can lead to single crystal growth failure.

[0003] Currently, the industry mainly uses the following cleaning methods: manual scraping or hammering, which is inefficient, inconsistent, and prone to chipping or micro-cracks at the ends of silicon rods; abrasive jet or air jet, although the high-speed airflow is clean, has insufficient impact force and is difficult to remove sintered SiC; abrasive jet can effectively remove hard contaminants, but abrasive particles are very easy to embed into the silicon matrix or mix with carbon powder, making subsequent separation difficult, recycling costs high, and posing a risk of non-silicon element contamination, making it unsuitable for recycling electronic-grade silicon rods. In view of this, a carbon head conveying jet cleaning system is provided to meet the needs of semiconductor-grade silicon material recycling scenarios, which can efficiently remove carbon / SiC residues in mounting holes without sacrificing materials, introducing impurities, or damaging the matrix. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a carbon head conveying and spraying cleaning system.

[0005] The technical solution adopted to solve the above technical problems is:

[0006] A carbon head conveying and jet cleaning system, comprising:

[0007] The conveying mechanism includes a quartz chain plate with a vertical plate at its upstream end. When the vertical plate moves upward, the silicon rods can be conveyed horizontally. When the vertical plate moves downward, it can block the silicon rods on the left side. At this time, the quartz chain plate drives the silicon rods on the right side to move to the right, so that adjacent silicon rods are separated by a distance, making it convenient to pick them up one by one.

[0008] The transfer mechanism includes a rotating module, which is a horizontally rotating platform. A robotic arm is provided at the top free end of the rotating module. The robotic arm is a multi-degree-of-freedom industrial robot that can perform flexible picking operations. A gripper is installed at the far end of the robotic arm. The gripper is electro-hydraulic driven and has high clamping accuracy, which avoids cracks on the surface of the silicon rod caused by excessive clamping force.

[0009] The cleaning mechanism includes a housing, a clamping component, a connecting component, a shifting component, and a hole-cleaning component, all of which are installed on the top surface of the housing. The clamping component and the shifting component are arranged side by side on the left and right sides. The end of the shifting component is equipped with the connecting component and the hole-cleaning component, and the connecting component and the hole-cleaning component can be switched below the clamping component.

[0010] The silicon rods are placed side-by-side on a quartz chain plate. The quartz chain plate prevents the silicon rods from being contaminated by metal. Similarly, the parts of the transfer and cleaning mechanisms that do not directly contact the silicon rods can be made of metal, but require an external protective cover or other protective layer. The parts that directly contact the silicon rods must be made of quartz or have a quartz coating to fully prevent the high-purity silicon rods from being contaminated by the equipment and ensure the purity of the recovered silicon rods. The clamping component clamps and positions the silicon rods transported by the transfer mechanism, fixing them vertically with the carbon head facing down, so that the carbon head can be removed from below and the silicon rods can be cleaned. The mounting hole at the lower end of the rod is cleaned. First, the shifting component moves the connecting component to below the carbon head. The connecting component is moved upward by the shifting component to clamp the part of the silicon rod exposed at the lower end of the carbon head. The shifting component moves the connecting component and the carbon head downward synchronously to disengage the carbon head from the mounting hole at the lower end of the silicon rod. The shifting component rotates to swap the position of the cleaning component and the connecting component. The cleaning component sprays and cleans the inner wall of the mounting hole at the lower end of the silicon rod from bottom to top to remove impurities such as carbon powder and silicon carbide, so that the part of the silicon rod that contacts the carbon head meets the recycling requirements. Finally, the transfer mechanism puts the cleaned silicon rod back onto the quartz chain plate and continues to be transported to the right for recycling.

[0011] Furthermore, the connecting component includes a sleeve, on the inner wall of which are arranged in a ring array of oblique blades, shorter at the top and longer at the bottom. The free ends of the oblique blades extend downward at an angle and form a cutting edge, and there are notches between adjacent oblique blades.

[0012] The above technical solution discloses a specific configuration of a coupling component. The sleeve is a vertically oriented annular ring. To achieve the function of the coupling component clamping the carbon head upwards and driving it downwards synchronously, multiple inclined blades are provided on the inner wall of the sleeve circumference. These inclined blades are stacked vertically and are designed to be flexible. Their ends are adapted to the outer contour of the carbon head. When the carbon head is inserted between the inclined blades, the blades are squeezed and bent, forming multiple points of force contact on the outer wall of the carbon head circumference. When the inclined blades move downwards, the lower end of the blades, due to the design of the cutting edge and its own springback tendency, cuts into the side wall of the carbon head to form a stable integral embedded connection, so that the carbon head can be smoothly driven to move downwards synchronously.

[0013] Furthermore, the shifting component includes a vertical cylinder, a turntable is installed at the lower end of the vertical cylinder, a support arm is installed on the vertical side wall of the turntable, a connecting member is connected to the free end of the support arm, the support arm can drive the connecting member to rotate horizontally by 180 degrees, and a top cylinder is installed on the side of the vertical cylinder away from the silicon rod at a position symmetrical to the clamping member.

[0014] Through the above technical solution, the vertical cylinder provides the power for the up and down movement of the bonding component, while the turntable rotates and repositions the bonding component and the cleaning component. For continuous operation, after a carbon head is removed, the cleaning component rotates to the lower end of the silicon rod to clean the mounting hole. After the support arm drives the bonding component to rotate horizontally by 180 degrees, the carbon head that was originally embedded in the upper part of the bonding component is rotated to the lower part. At this time, the top cylinder extends and inserts into the sleeve from top to bottom, which can push the carbon head down to overcome the resistance of the inclined blade. During the process, the outer layer of carbon powder scraped off by the blade of the inclined blade and the carbon head go down together. The hopper is set directly below the top cylinder to collect the falling carbon heads for centralized processing. Due to the horizontal design of the support arm, the bonding component is located far away from the silicon rod, so it does not interfere with the cleaning of the silicon rod. If there is a concern that carbon powder may scatter onto the surface of the silicon rod, a negative pressure suction device can be set up nearby in the box to capture and collect the floating carbon powder in a timely manner.

[0015] Furthermore, the shifting component also includes a second support arm, the free end of which is equipped with a hole-cleaning component, and the second support arm and the first support arm are on the same horizontal straight line.

[0016] Through the above technical solution, in order to ensure the balance of the transposition component, a second support arm is set to connect the hole cleaning component, which ensures the balance of the turntable of the transposition component when it rotates, avoids uneven wear of the internal bearings, and allows the hole cleaning component and the connecting component to be repositioned at a fixed point without the need for translation or other actions, reducing the complexity of the structure and facilitating maintenance.

[0017] Furthermore, the cleaning component includes a ring frame, with a vertical clearance hole at the center of the ring frame. An electrically controlled gimbal is installed at the lower end of the ring frame, and a primary cooler is vertically installed on the electrically controlled gimbal at the center line of the clearance hole. An air inlet pipe is provided at the inlet end of the primary cooler, and a secondary cooler is sleeved in the middle section of the primary cooler. A spray pipe is connected to the outlet end of the primary cooler, and a bypass hole is provided around the clearance hole in the ring frame.

[0018] The above technical solution provides a specific configuration for a hole cleaning component. Using argon gas as the gas source, during the cleaning of the mounting hole, the inlet pipe continuously delivers high-pressure argon gas to the first-stage cooler for cooling, and then supplements the cooling through the second-stage cooler, reducing the temperature of the high-pressure argon gas to below -100 degrees Celsius. The high-pressure, low-temperature argon gas flow is ejected from the nozzle and impacts the surface of the mounting hole. The electrically controlled gimbal can drive the nozzle to spiral feed, allowing the argon gas to fully act on the inclined inner wall and bottom surface of the mounting hole, causing the carbon powder deep inside to fall off, the surface silicon carbide to become brittle due to cold, and to peel off under the action of the high-pressure gas flow. Furthermore, the low-temperature argon gas jet promptly removes the temperature of the inner wall of the mounting hole, preventing surface heating due to jet friction, inhibiting thermal oxidation at the silicon rod mounting hole during cleaning, and ensuring the purity of the silicon rod. At the same time, during purging, an external negative pressure collection device can be connected to the avoidance hole position to attract and collect falling solid impurities in a timely manner, preventing contamination of the silicon rod from scattering and dispersing.

[0019] Furthermore, the primary cooling unit includes a shaft tube, with a main cold source at the lower end of the shaft tube. The top of the main cold source is provided with a cone at the same height as the air inlet pipe. The inner wall of the shaft tube and the outer wall of the cone form an annular heat exchange cavity that is wider at the top and narrower at the bottom. The outlet end of the heat exchange cavity is provided with a vertically upward-extending constriction cavity with a gradually decreasing inner diameter. The secondary cooling unit includes a supplementary cold source, which is coaxially sleeved at the constriction cavity. A heat insulation shell is sleeved on the outside of the supplementary cold source.

[0020] Through the above technical solution, to achieve rapid cooling, the first-stage cooler is equipped with a cone at the outlet end of the inlet pipe. This cone disperses the concentrated argon gas on both sides and gathers it in the heat exchange chamber to form turbulence. The turbulence is fully contacted with the cone to achieve heat exchange. The main cold source uses circulating liquid nitrogen as the medium, which can rapidly reduce the temperature of the argon gas to minus 100 degrees Celsius or even lower. The design of the constriction cavity, by extending the path and reducing the inner diameter, allows the turbulent argon gas to gather and accelerate again, increasing the outlet flow rate and ensuring the jet speed and impact force. The second-stage cooler absorbs and transports the heat generated by the friction between the inner wall of the constriction cavity and the argon gas when the argon gas is accelerated by constriction. The supplementary cold source uses circulating liquid nitrogen, and the heat insulation shell avoids absorbing heat from the atmosphere. The supplementary cold source and the main cold source use a unified liquid nitrogen source, avoiding the design of an independent liquid nitrogen supply source. The coordinated arrangement of argon gas cooling and argon gas acceleration ensures that the surface material of the mounting hole is successfully bombarded and removed.

[0021] Furthermore, a sand feeder is provided between the outlet end of the primary cooler and the spray pipe. The sand feeder includes an annular shell with a cylindrical mixing chamber inside. A feed pipe is provided along the tangential direction of the inner wall of the mixing chamber. The reduced diameter chamber is connected to the inlet end of the mixing chamber, and the spray pipe is connected to the outlet end of the mixing chamber.

[0022] To improve the cleaning effect on silicon carbide through the above technical solution, an airflow mixed with nano-sized quartz sand is introduced through a feeding pipe before the high-speed airflow is ejected. The nano-sized quartz sand mixes with the argon airflow in the mixing chamber, and the tangential introduction method minimizes interference with the argon ejection speed. Using quartz sand as an abrasive for jet polishing significantly reduces the cleaning and polishing time compared to simple airflow blasting. Using quartz sand for solid-gas mixed jet polishing, and using quartz sand as a medium without introducing other non-metallic materials, improves the cleaning effect without affecting the purity of the silicon rod.

[0023] Furthermore, a particle generator is provided between the outlet end of the primary cooler and the nozzle. The particle generator includes a main body, and inside the main body, from bottom to top, there are an expansion section one, an expansion section two, and a generation chamber. The cone angle of the expansion section one is twice that of the expansion section two. The generation chamber is cylindrical and has the same width as the widest part of the expansion section two. A converging section is provided on the inner wall of the connection between the nozzle and the generation chamber. The cone angle of the converging section is no greater than three degrees. The converging chamber is connected to the inlet end of the expansion section one.

[0024] Using the above technical solution, high-purity quartz sand as a grinding abrasive is difficult to separate from carbon powder and silicon carbide after collection, resulting in high cleaning costs. A particle generator is used as an alternative. Argon gas accelerated in the converging section reaches the speed of sound. The first and second expansion sections form a double-cone expansion zone. Here, due to the increased cross-sectional area of ​​the pipe, the argon gas accelerates to the speed of sound in the converging section and then enters the expansion section for further acceleration to supersonic speed (Mach>2). Due to the supersonic flow expansion and acceleration, the flow velocity along the pipe continuously increases, while the pressure, density, and temperature continuously decrease. During adiabatic expansion, the gas does work on the surroundings, and the decrease in its internal energy equals the work done. Adiabatic expansion mainly manifests as a decrease in molecular kinetic energy. This decrease in internal energy is converted into gas kinetic energy, achieving acceleration. Furthermore, during this process… Potential energy generally increases slightly; at the same time, adiabatic expansion causes the gas to do work on the outside, consuming internal energy, resulting in a sharp drop in static temperature. When the temperature is below the freezing point (the freezing point of argon is -189.3°C) and the supersaturation of argon is greater than 10, argon molecular clusters will nucleate and form nano-sized solid argon particles. During the convergence phase, the gas flow slightly gathers and is sprayed onto the surface of the mounting hole at high speed. Because the gas flow speed is high, the solid argon does not have time to vaporize before contacting the mounting hole. Using solid argon as a polishing abrasive can also greatly increase the polishing and cleaning efficiency of the inner wall of the mounting hole. Furthermore, the solid argon heats up and vaporizes when rubbing the inner wall of the mounting hole, leaving no residue. It can also more effectively control the surface temperature rise of the mounting hole, resulting in a better polishing effect. The cost of using solidified argon as an abrasive is also lower.

[0025] Furthermore, the clamping member includes a ring array of driving cylinders, the extension line of the extension and retraction direction of the driving cylinders intersects the center line of the silicon rod, the end of the driving cylinder is provided with a moving frame, the moving frame is provided with a quartz contact piece on the side facing the silicon rod, the lower end of the moving frame is provided with a slide bar parallel to the extension and retraction direction of the driving cylinder, and the end of the driving cylinder is fixedly installed with a guide seat that is slidably connected to the slide bar.

[0026] The above technical solution discloses a specific configuration of a clamping component, which sets at least three clamping components arranged in a ring for centered clamping. During installation, the drive cylinder and the housing are fixedly connected, and a vertical moving frame is installed at the free end of the drive cylinder. During clamping, the drive cylinder extends, causing the moving frame to press against the vertical sidewall of the silicon rod to complete the clamping. Furthermore, the contact piece adapts to the outer contour of the silicon rod, with a large contact area to prevent the silicon rod from cracking under pressure. The contact piece is made of the same material as the silicon rod to avoid contaminating the silicon rod. Because the curvature of the contact piece matches the arc surface of the silicon rod, if the contact piece undergoes radial lateral movement or twisting, it will cause one side of the contact piece to contact the silicon rod while the other side tilts up, significantly reducing the contact area. Therefore, a slide bar and guide seat are set for linear guidance to ensure linear movement of the contact piece and prevent radial twisting or lateral movement.

[0027] Furthermore, the conveying mechanism also includes a baffle, which is placed at both ends of the silicon rod parallel to the travel direction of the quartz chain plate, and a horizontally extending partition block is installed in the middle section of the baffle facing the quartz chain plate.

[0028] With the above technical solution, because the silicon rod is rolled on the quartz chain plate, when the vertical plate blocks the silicon rod, the quartz chain plate continues to move forward and the silicon rod can roll, avoiding sliding friction between the silicon rod and the quartz chain plate. At the same time, in order to prevent the rolling silicon rod from detaching from the quartz chain plate from the front and rear sides, baffles are set on both sides. The baffles are equipped with quartz coatings that are in direct contact with the silicon rod. In addition, in order to prevent the cleaned silicon rod from rolling to the left and being mistakenly picked up and cleaned again, partition blocks are set to divide the space of the quartz chain plate, so that the cleaned silicon rod on the right side will not roll to the left, and the uncleaned silicon rod on the left side will not roll to the right, avoiding repeated cleaning and missed cleaning.

[0029] The beneficial effects of this invention are as follows:

[0030] This invention uses a deeply pre-cooled inert gas for jet cleaning, which not only has high-speed impact capability, but also achieves active cooling of the inner wall of the silicon rod mounting hole during the cleaning process. Compared with the existing technology that relies on the bombardment method of room temperature or high temperature high-speed airflow, this solution effectively suppresses the local temperature rise caused by friction, avoids thermal oxidation or micro-cracks on the silicon surface during the cleaning process, and significantly improves the structural integrity and surface cleanliness of high-purity silicon materials.

[0031] (2) The present invention uses traditional quartz sand as the spraying method of solid abrasive, which avoids the problems of abrasive embedding, difficulty in separation and cross-contamination caused by conventional abrasive bombardment. It also sets up gas solidified microparticles as a substitute for the material. The microparticles used are immediately vaporized after cleaning, leaving no residue, which fundamentally solves the problem of abrasive recycling. At the same time, it avoids the introduction of non-silicon impurities and ensures that the recycled silicon rod meets the high purity requirements of semiconductor grade.

[0032] (3) This invention constructs a high-purity pollution-proof working environment through a full quartz contact design, inert gas closed-loop recovery and negative pressure dust removal system; combined with automatic isolation feeding, rotary transfer and workstation switching mechanism, it realizes full-process automation of carbon head removal, hole cleaning and waste collection, greatly improves processing efficiency and process consistency, and is suitable for large-scale green recycling of polysilicon waste from photovoltaic grade to semiconductor grade. Attached Figure Description

[0033] Figure 1 This is an overall structural diagram of the present invention;

[0034] Figure 2 This is a schematic diagram of the structure between the conveying mechanism, the transfer mechanism, and the silicon rod of the present invention;

[0035] Figure 3 This is a schematic diagram of the cleaning mechanism of the present invention;

[0036] Figure 4 This is a schematic diagram showing the location of the cleaning mechanism of the present invention;

[0037] Figure 5 This is a schematic diagram of the structure of the clamping member of the present invention;

[0038] Figure 6 This is a schematic diagram of the cleaning mechanism of the present invention;

[0039] Figure 7 This is a schematic diagram of the structure of the carbon head and the connector of the present invention;

[0040] Figure 8 This is a schematic diagram of the structure of the hole-cleaning component of the present invention;

[0041] Figure 9 This is a schematic diagram showing the position of the hole-cleaning component of the present invention with the sand feeder installed;

[0042] Figure 10 This is a schematic diagram of the state of the hole-cleaning component of the present invention with a particle generator installed.

[0043] Reference numerals: 1. Silicon rod; 2. Carbon head; 3. Conveying mechanism; 31. Quartz chain plate; 32. Vertical plate; 33. Partition block; 34. Baffle; 4. Transfer mechanism; 41. Rotating module; 42. Robotic arm; 43. Gripper; 5. Cleaning mechanism; 51. Box; 52. Hopper 1; 53. Hopper 2; 6. Clamping component; 61. Moving frame; 611. Contact piece; 612. Slide bar; 62. Drive cylinder; 621. Guide seat; 7. Connecting component; 71. Top cylinder; 72. Sleeve; 73. Inclined plate; 74. Cutting edge; 75. Notch; 8. Transposition component; 81. Vertical cylinder; 82. Turntable; 83. Support arm 1; 84. Support arm II; 9. Cleaning component; 91. Ring frame; 911. Bypass hole; 912. Clearance hole; 913. Baffle curtain; 92. Primary cooler; 921. Shaft tube; 922. Air inlet pipe; 923. Main cold source; 924. Cone head; 925. Heat exchange chamber; 926. Diameter reduction chamber; 93. Electric control pan-tilt unit; 94. Secondary cooler; 941. Supplementary cold source; 942. Heat insulation shell; 95. Sand feeder; 951. Shell; 952. Feed pipe; 953. Mixing chamber; 96. Particle generator; 961. Main body; 962. Expansion section one; 963. Expansion section two; 964. Generating chamber; 97. Nozzle; 971. Converging section. Detailed Implementation

[0044] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0045] Reference Figures 1 to 10 This embodiment provides an automated system for removing the carbon head at the bottom and cleaning the mounting holes during the recycling of high-purity silicon rods. The system comprises three core modules: a conveying mechanism 3, a transfer mechanism 4, and a cleaning mechanism 5. All structures in direct contact with the silicon rod 1 are made of quartz or coated with a high-purity quartz coating to prevent metal contamination and ensure the purity of the recycled silicon rod.

[0046] Regarding the conveying mechanism 3, it includes a quartz chain plate 31, made of fused quartz or with a quartz coating, driven by a servo motor and a reducer, with an adjustable speed range of 0.1-0.5 m / min. The surface is polished to Ra≤0.2μm to prevent scratching the silicon rod surface. The vertical plate 32 is located at the upstream inlet of the quartz chain plate 31, perpendicular to the conveying direction, made of quartz plate, with a width slightly larger than the diameter of the silicon rod. It is driven by a cylinder for lifting, with a stroke of 200 mm and a response time ≤0.5 s. When the vertical plate 32 is raised, it blocks subsequent silicon rods from entering the picking area; when it is lowered, it allows silicon rods to pass through, thereby realizing "single-bar interval" feeding.

[0047] Regarding the transfer mechanism 4, it includes a rotating module 41, which adopts a high-precision rotary table with a positioning accuracy of ±0.02° and an adjustable rotation speed of 0–3 rpm. It supports jog / continuous mode and is installed between the right end of the conveying mechanism 3 and the cleaning mechanism 5, enabling angle switching from 90° to 180°. The robotic arm 42 is a six-axis multi-degree-of-freedom industrial robot with a repeatability of ±0.03 mm and a maximum load of 10 kg (meeting the weight of a Φ150×300 mm silicon rod of approximately 2–3 kg). The control system is an integrated PLC with vision guidance and can be equipped with CCD alignment. The gripper 43 is an electro-hydraulic hybrid servo drive with force feedback closed-loop control. The gripping surface is embedded with a high-purity quartz pad, and the gripping force range is 1–80 N and can be programmably set. The default setting is 30 N (which has been experimentally verified as a safe threshold that will not cause cracking). It can adapt to the outer circle of the silicon rod and achieve three-point self-centering gripping.

[0048] The cleaning mechanism 5 includes a housing 51, made of 304 stainless steel with a PTFE anti-contamination layer. The internal environment is set to positive pressure clean air (Class 1000) to prevent external particles from entering. The clamping component 6 is a horizontally opposed clamping method driven by a pneumatic slide. The shifting component 8 is a linear and rotary composite motion platform (such as a servo electric slide + rotary cylinder combination). The connecting component 7 uses a conical sleeve 72 with a quartz coating and an elastic snap ring mechanism. The inner diameter is adapted to the outer diameter of the carbon head 2 (typically Φ30–50mm). The cleaning component 9 is equipped with a high-pressure nozzle that performs low-temperature, high-speed spraying with high-pressure inert gas (Ar). The nozzle material is quartz or ceramic, with an orifice diameter of Φ0.3mm. The cleaning path is a spiral upward scanning path from bottom to top, covering the entire inner wall of the mounting hole (typically 30–50 mm deep).

[0049] The working principle of this embodiment is as follows:

[0050] During the feeding stage, multiple silicon rods 1 are placed side by side on the quartz chain plate 31 and conveyed to the right at a uniform speed with the chain plate. When the leading silicon rod reaches the predetermined pick-up position, the sensor triggers a signal, and the vertical plate 32 immediately rises to block the subsequent silicon rods, ensuring that only a single silicon rod exists at the current work station.

[0051] Grasping and transferring: The robotic arm 42 is activated, and the gripper 43 gently clamps the end of the silicon rod away from the carbon head 2 with a preset clamping force (e.g., 30N). Subsequently, the rotating module 41 drives the robotic arm 42 to rotate horizontally by 90°, moving the silicon rod directly above the cleaning mechanism 5 and slowly lowering it into the V-groove of the clamping member 6;

[0052] Vertical positioning and clamping, clamping member 6 is horizontally closed, precisely fixing silicon rod 1 in a vertical state, carbon head 2 naturally hangs down in the lower space inside box 51, with its bottom end exposed about 10–20 mm.

[0053] After the carbon head is removed, the shifting component 8 drives the connecting component 7 to rotate directly below the carbon head 2. Then, it moves upward and precisely fits into the lower end of the carbon head 2. Then, it moves downward and applies a controllable thrust (such as 100N) to make the carbon head 2 overcome the static friction between itself and the silicon rod mounting hole and possible sintering adhesion, and smoothly move downward and detach. Then, the connecting component 7 rotates horizontally and carries the carbon head 2 to move synchronously to the second hopper 53.

[0054] When the workstation is switched and the shifting part 8 rotates 180°, the hole cleaning part 9 is moved to the original position of the connecting part 7, that is, on the central axis directly below the silicon rod 1.

[0055] The cleaning process begins with high-pressure inert gas being sprayed at high speed. The nozzle rises at a constant speed of 0.5 mm / s along the Z-axis while rotating at a low speed (1–2 rpm) around the axis, achieving 360° full coverage cleaning of the inner wall of the mounting hole. The cleaning process lasts for 5–10 seconds. The solid waste falling from below is collected by the hopper 52, and the floating impurities are discharged through the bottom negative pressure suction system.

[0056] After resetting and re-feeding, and cleaning is completed, the robotic arm 42 re-clamps the silicon rod 1, the clamping part 6 is released, the rotating module 41 rotates back to above the conveying mechanism 3, and puts the clean silicon rod back onto the quartz chain plate 31. The vertical plate 32 descends to release the next silicon rod, and the cycle continues.

[0057] In a further embodiment, a specific configuration of the coupling 7 is disclosed, referring to... Figure 7 The connecting component 7 includes a sleeve 72. The inner wall of the sleeve 72 is equipped with a ring array of inclined blades 73, which are shorter at the top and longer at the bottom. The free ends of the inclined blades 73 extend downwards and form cutting edges 74. There are notches 75 between adjacent inclined blades 73. The sleeve 72 is a vertically oriented ring. In order to realize the function of the connecting component 7 in clamping the carbon head 2 upwards and driving the carbon head 2 downwards synchronously, multiple inclined blades 73 are provided on the inner wall of the circumference of the sleeve 72. These inclined blades 73 are stacked on top of each other, and adopt a flexible and deformable design. The ends are adapted to the outer contour of the carbon head 2. When the carbon head 2 is inserted between the inclined blades 73, the inclined blades 73 are squeezed and bent, forming multiple contact points on the outer wall of the circumference of the carbon head 2. When the inclined blades 73 move downwards, the lower end of the inclined blades 73, due to the design of the cutting edges 74 and its own springback tendency, cuts into the side wall of the carbon head 2 to form a stable integral embedded connection, so that the carbon head 2 can be smoothly driven to move downwards synchronously.

[0058] In a further embodiment, refer to Figure 4 and Figure 6The shifting component 8 includes a vertical cylinder 81, with a turntable 82 mounted on its lower end. The vertical cylinder 81 provides the power for the vertical movement of the connecting component 7, while the turntable 82 performs the rotational shifting of the connecting component 7 and the hole-cleaning component 9. A support arm 83 is mounted on the vertical side wall of the turntable 82, with the connecting component 7 connected to its free end. The support arm 83 can drive the connecting component 7 to rotate horizontally by 180 degrees. A top cylinder 71 is mounted symmetrically on the side of the vertical cylinder 81 away from the silicon rod 1, on the clamping component 6. For continuous operation, after a carbon head 2 is removed, the hole-cleaning component 9 rotates to the lower end of the silicon rod 1 to clean the mounting hole. After the support arm 83 drives the connecting component 7 to rotate horizontally by 180 degrees, the original... The carbon head 2, which is embedded in the upper part of the connector 7, is rotated to the lower part. At this time, the top cylinder 71 extends and inserts into the sleeve 72 from top to bottom, which can push the carbon head 2 to overcome the resistance of the inclined blade 73 and move downward. During the process, the outer layer of carbon powder scraped off by the blade 74 of the inclined blade 73 moves downward together with the carbon head 2. The hopper 2 53 is set directly below the top cylinder 71 to collect the falling carbon head 2 for centralized processing. Due to the horizontal design of the support arm 1 83, the connector 7 is located far away from the silicon rod 1, so there is no interference with the cleaning of the silicon rod 1. If it is to prevent carbon powder from escaping to the surface of the silicon rod 1, a negative pressure suction device can be set up nearby in the box 51 to capture and collect the floating carbon powder in time.

[0059] In a further embodiment, to ensure the balance of the transposition member 8, refer to Figure 6 The shifting component 8 also includes a second support arm 84, with a cleaning component 9 installed at the free end of the second support arm 84. The second support arm 84 and the first support arm 83 are on the same horizontal straight line. The second support arm 84 is set to connect the cleaning component 9, ensuring the balance of the turntable 82 of the shifting component 8 when it rotates, avoiding uneven wear of the internal bearings, and allowing the cleaning component 9 and the connecting component 7 to be shifted at a fixed point without the need for translation or other actions, reducing the complexity of the structure and facilitating maintenance.

[0060] In a further embodiment, a specific configuration of the hole-cleaning component 9 is provided, referring to... Figure 8The hole cleaning component 9 includes a ring frame 91, with a vertical clearance hole 912 at the center of the ring frame 91. An electrically controlled pan-tilt unit 93 is installed at the lower end of the ring frame 91. A primary cooler 92 is vertically installed on the pan-tilt unit 93 at the center line of the clearance hole 912. An inlet pipe 922 is provided at the inlet end of the primary cooler 92. A secondary cooler 94 is fitted in the middle section of the primary cooler 92. A nozzle 97 is connected to the outlet end of the primary cooler 92. A bypass hole 911 is provided around the clearance hole 912 in the ring frame 91. Argon gas is used as the gas source. During the cleaning of the installation hole, the inlet pipe 922 continuously delivers high-pressure argon gas to the primary cooler 92 for cooling. The secondary cooler 94 then provides supplemental cooling, reducing the temperature of the high-pressure argon gas to below zero. Below 100 degrees Celsius, high-pressure, low-temperature argon gas is ejected from nozzle 97 and impacts the surface of the mounting hole. The electrically controlled gimbal 93 has at least three electro-hydraulic telescopic cylinders, which can drive nozzle 97 to spiral feed, so that the argon gas can fully act on the inclined inner wall and bottom surface of the mounting hole, causing the carbon powder deep inside to fall off, the surface silicon carbide to become brittle due to cold, and peel off under the action of high-pressure gas flow. In addition, when the low-temperature argon gas is injected, it can promptly remove the temperature of the inner wall of the mounting hole, avoid the surface temperature rise caused by the jet friction, suppress the thermal oxidation of the silicon rod 1 mounting hole during cleaning, and ensure the purity of silicon rod 1. At the same time, during the purging, the avoidance hole 912 can be connected to an external negative pressure collection device to attract and collect the falling solid impurities in a timely manner, preventing the silicon rod 1 from being contaminated and scattered.

[0061] In a further embodiment, to achieve rapid cooling, refer to Figure 9The primary cooling unit 92 includes a shaft tube 921. A main cold source 923 is located at the lower end of the shaft tube 921. A cone 924 is located at the top of the main cold source 923 at the same height as the inlet pipe 922. The inner wall of the shaft tube 921 and the outer wall of the cone 924 form an annular heat exchange cavity 925, wider at the top and narrower at the bottom. A vertically extending, narrowing cavity 926 is located at the outlet end of the heat exchange cavity 925. The inner diameter of the narrowing cavity 926 gradually decreases. The cone 924 at the outlet end of the inlet pipe 922 disperses the concentrated argon gas on both sides and gathers it in the heat exchange cavity 925 to form turbulence, achieving heat transfer through full contact with the cone 924. The main cold source 923 uses circulating liquid nitrogen as a medium, which can rapidly reduce the temperature of the argon gas to minus one hundred degrees Celsius or even lower. The design of the narrowing cavity 926... By extending the path and narrowing the inner diameter, the turbulent argon gas is re-aggregated and accelerated, increasing the outlet flow rate and ensuring the injection speed and impact force. The secondary cooler 94 includes a supplementary cold source 941, which is coaxially sleeved at the position of the narrowing cavity 926. A heat insulation shell 942 is sleeved on the outside of the supplementary cold source 941. When the argon gas narrows and accelerates, the secondary cooler 94 absorbs and transports the heat generated by the friction between the inner wall of the narrowing cavity 926 and the argon gas. The supplementary cold source 941 uses circulating liquid nitrogen, and the heat insulation shell 942 avoids absorbing heat from the atmosphere. The supplementary cold source 941 and the main cold source 923 use a unified liquid nitrogen source to avoid designing an independent liquid nitrogen supply source. The coordinated arrangement of argon gas cooling and argon gas acceleration ensures that the surface material of the mounting hole is successfully bombarded and removed.

[0062] In a further embodiment, to improve the cleaning effect on silicon carbide, refer to Figure 9 A sand feeder 95 is provided between the outlet end of the primary cooler 92 and the nozzle 97. The sand feeder 95 includes an annular shell 951, inside which is a cylindrical mixing chamber 953. A feed pipe 952 is provided along the tangential direction of the inner wall of the mixing chamber 953. A narrowing cavity 926 is connected to the inlet end of the mixing chamber 953, and the nozzle 97 is connected to the outlet end of the mixing chamber 953. Before the high-speed airflow is ejected, an airflow mixed with nano-sized quartz sand is introduced through the feed pipe 952. The nano-sized quartz sand is located at the position of the mixing chamber 953 and... Argon gas is mixed with airflow and introduced tangentially to minimize interference with the argon gas ejection velocity. Quartz sand is used as an abrasive for jet polishing. Compared with simple airflow blasting, the cleaning and polishing time is greatly reduced. The solid-gas mixed jet polishing with quartz sand, and the use of quartz sand as a medium does not introduce other non-metallic materials, which improves the cleaning effect without affecting the purity of silicon rod 1. A baffle 913 is set on the lower side of the nozzle 97 to collect the falling quartz powder and solid impurities so that they can be collected in the bypass hole 911.

[0063] In a further embodiment, refer to Figure 8 and Figure 10A particle generator 96 is installed between the outlet end of the primary cooler 92 and the nozzle 97. The particle generator 96 includes a main body 961, inside which, from bottom to top, are an expansion section 962, an expansion section 963, and a generating chamber 964. The expansion section 962 has a cone angle of 8° and a length of 8 mm; the expansion section 963 has a cone angle of 4° and a length of 8 mm. The cone angle of the expansion section 962 is twice that of the expansion section 963, forming an asymmetric double-cone expansion structure. The generating chamber 964 is cylindrical with an inner diameter of 3.8 mm. The nozzle 97 has a diameter of 1.2 mm and a length of 5 mm, and is the same width as the outlet end of the expansion section 963. It is used to stabilize the supersonic flow field and extend the cryogenic residence time. The inner wall of the nozzle 97 where it connects to the generation chamber 964 is provided with a converging section 971. The cone angle of the converging section 971 is 2.5°, which is only used to constrain the jet divergence angle and does not cause flow blockage. The narrowing chamber 926 of the first-stage cooler 92 is connected to the inlet end of the expansion section 962, and the throat diameter is 1.2 mm. The working medium is high-purity argon gas (purity ≥99.9999%, i.e., 6N). After being pre-cooled to −100±3°C and pressurized to 8MPa by the first-stage cooler 92, it enters the particle generator 96. The argon gas first passes through the throat (Ø The gas is accelerated to the speed of sound (Mach=1) at 1.2 mm, and then enters the biconical expansion region (expansion section 1 962 and expansion section 2 963). In this region, the gas cross-sectional area increases, and the flow velocity continues to increase to Mach≈2.8 (approximately 800 m / s). According to the principle of adiabatic expansion, the gas does work on the surroundings, resulting in a decrease in internal energy and a sharp drop in static temperature. According to CFD simulation and thermodynamic calculation, the static temperature at the end of the expansion section can reach −205°C, which is significantly lower than the freezing point of argon (−189.3°C). When the local supersaturation S>50 and the residence time τ>5μs, argon molecules undergo homogeneous nucleation, forming nanoscale solid argon particles of 50–150 nm, with a concentration reaching 10. 9 The process, with particles / cm³, requires no addition of any solid abrasives (such as silica sand), completely avoiding the high costs and secondary pollution problems caused by the difficulty of abrasive embedding or separation in traditional jet cleaning. The supersonic airflow containing solid particles enters the convergence section 971. Due to the convergence cone angle of only 2.5°, the airflow is not decelerated or pressurized, only slightly focused, with the jet beam diameter controlled to ≤1.0mm. This is suitable for tapered mounting holes deep into the ends of polycrystalline silicon rods (typical hole depth 15–25mm, orifice diameter 8–15mm). During the cleaning process, solid argon particles impact the inner wall of the mounting hole at a speed of 800 m / s. Utilizing kinetic energy impact and localized micro-explosion effects, free carbon, silicon carbide debris, and surface oxide film are efficiently stripped away. The particles undergo endothermic sublimation during friction, Ar(s) → Ar(g), leaving no residue. The sublimation process simultaneously cools the silicon surface to approximately −50°C, effectively inhibiting thermal damage and re-oxidation. After cleaning, the surface carbon concentration is <1×10¹² atoms / cm² (XPS detection), and the oxygen increment is <1×10¹². 5The argon gas concentration is 1000 atoms / cm³, meeting the semiconductor-grade FZ silicon recycling standard. The detached particles generated during cleaning are drawn in real time by the annular negative pressure hood (−1kPa) at the orifice. After continuous treatment by the low-temperature cold trap (−150°C), molecular sieve and palladium membrane purifier, the argon gas recovery rate is >95%, realizing closed-loop operation.

[0064] In a further embodiment, a specific configuration of the clamping member 6 is disclosed, referring to... Figure 5 The clamping element 6 includes a ring array of drive cylinders 62. The extension line of the drive cylinders 62 in the extension and retraction direction intersects the centerline of the silicon rod 1. The end of the drive cylinder 62 is provided with a movable frame 61. The movable frame 61 is provided with a quartz contact piece 611 on the side facing the silicon rod 1. At least three clamping elements 6 are arranged in a ring for centering clamping. During installation, the drive cylinder 62 is fixedly connected to the housing 51. A vertical movable frame 61 is installed at the free end of the drive cylinder 62. During clamping, the drive cylinder 62 extends, driving the movable frame 61 to press the vertical sidewall of the silicon rod 1 to complete the clamping. Furthermore, the contact piece 611 adapts to the outer contour of the silicon rod 1, with a large contact area to avoid pressure on the silicon rod 1. The contact piece 611 is made of the same material as the silicon rod 1 to avoid contaminating the silicon rod 1. The lower end of the moving frame 61 is provided with a slide bar 612 parallel to the extension and retraction direction of the drive cylinder 62. The end of the drive cylinder 62 is fixedly installed with a guide seat 621 that is slidably connected to the slide bar 612. Because the curvature of the contact piece 611 is adapted to the arc surface of the silicon rod 1, if the contact piece 611 undergoes radial lateral movement or twisting, it will cause one side of the contact piece 611 to contact the silicon rod 1 while the other side will lift up, and the contact area will be greatly reduced. Therefore, the slide bar 612 and the guide seat 621 are set to provide linear guidance to ensure that the contact piece 611 moves in a straight line and prevents radial twisting or lateral movement.

[0065] In a further embodiment, because the silicon rod 1 is rolled on the quartz chain plate 31, refer to Figure 2 The conveying mechanism 3 also includes a baffle 34, which is placed at both ends of the silicon rod 1 parallel to the traveling direction of the quartz chain plate 31. So when the vertical plate 32 blocks the silicon rod 1, the quartz chain plate 31 continues to move forward and the silicon rod 1 can roll, avoiding sliding friction between the silicon rod 1 and the quartz chain plate 31. At the same time, in order to prevent the rolling silicon rod 1 from detaching from the quartz chain plate 31 from the front and rear sides, the baffle 34 is set on both sides. The baffle 34 is provided with a quartz coating that is in direct contact with the silicon rod 1. In addition, in order to prevent the cleaned silicon rod 1 from rolling to the left and being accidentally picked up and cleaned again, a horizontally extending partition block 33 is installed in the middle section of the baffle 34 facing the quartz chain plate 31. The partition block 33 is set to divide the space of the quartz chain plate 31, so that the cleaned silicon rod 1 on the right side will not roll to the left, and the uncleaned silicon rod 1 on the left side will not roll to the right, avoiding repeated cleaning and missed cleaning.

[0066] The above are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention.

Claims

1. A carbon head conveying and spraying cleaning system, characterized in that, include: The conveying mechanism (3) includes a quartz chain plate (31), and a vertical plate (32) is provided upstream of the quartz chain plate (31). The vertical plate (32) can move up and down to block and release the silicon rod (1) with carbon head (2). The transfer mechanism (4) includes a rotating module (41), and a robotic arm (42) is provided at the top free end of the rotating module (41). The robotic arm (42) is a multi-degree-of-freedom industrial robot, and a gripper (43) is installed at the far end of the robotic arm (42). The cleaning mechanism (5) includes a clamping member (6), a connecting member (7), a shifting member (8), and a hole cleaning member (9). The clamping member (6) and the shifting member (8) are arranged side by side. The shifting member (8) has the connecting member (7) and the hole cleaning member (9) installed below the clamping member (6). The cleaning component (9) includes a ring frame (91), a vertical clearance hole (912) is provided at the center of the ring frame (91), an electric control gimbal (93) is installed at the lower end of the ring frame (91), a primary cooler (92) is vertically installed on the electric control gimbal (93) at the center line of the clearance hole (912), an air inlet pipe (922) is provided at the inlet end of the primary cooler (92), a secondary cooler (94) is sleeved in the middle section of the primary cooler (92), a nozzle (97) is connected to the outlet end of the primary cooler (92), and a bypass hole (911) is provided around the clearance hole (912) of the ring frame (91). The primary cooling unit (92) includes a shaft tube (921), with a main cold source (923) at the lower end of the shaft tube (921). The top of the main cold source (923) is provided with a cone (924) at the same height as the air inlet pipe (922). The inner wall of the shaft tube (921) and the outer wall of the cone (924) form an annular heat exchange cavity (925) that is wider at the top and narrower at the bottom. The outlet end of the heat exchange cavity (925) is provided with a vertically upward-extending narrowing cavity (926). The inner diameter of the narrowing cavity (926) gradually decreases. The secondary cooling unit (94) includes a supplementary cold source (941), which is coaxially sleeved in the position of the narrowing cavity (926). A sand feeder (95) is provided between the outlet end of the primary cooler (92) and the nozzle (97). The sand feeder (95) includes an annular shell (951). A cylindrical mixing chamber (953) is built into the shell (951). A feed pipe (952) is provided along the tangential direction of the inner wall of the mixing chamber (953) in the shell (951). The reduced diameter chamber (926) is connected to the inlet end of the mixing chamber (953). The nozzle (97) is connected to the outlet end of the mixing chamber (953). The clamping member (6) clamps the silicon rod (1) delivered by the transfer mechanism (4) and fixes the silicon rod (1) vertically with the carbon head (2) facing down. The connecting member (7) drives the carbon head (2) to move downward and detach from the silicon rod (1). The hole cleaning member (9) sprays and cleans the inner wall of the mounting hole at the lower end of the silicon rod (1). The shifting member (8) drives the connecting member (7) and the hole cleaning member (9) to move closer to and further away from the silicon rod (1).

2. The carbon head conveying and spraying cleaning system according to claim 1, characterized in that, The connector (7) includes a sleeve (72), and the inner wall of the sleeve (72) is equipped with a ring array of inclined plates (73) that are shorter at the top and longer at the bottom. The free end of the inclined plate (73) extends downward and forms a cutting edge (74). There is a notch (75) between adjacent inclined plates (73).

3. The carbon head conveying and spraying cleaning system according to claim 2, characterized in that, The shifting component (8) includes a vertical cylinder (81), a turntable (82) is installed at the lower end of the vertical cylinder (81), a support arm (83) is installed on the vertical side wall of the turntable (82), and a connecting component (7) is connected to the free end of the support arm (83). The support arm (83) can drive the connecting component (7) to rotate horizontally by 180 degrees. A top cylinder (71) is installed on the side of the vertical cylinder (81) away from the silicon rod (1) at a symmetrical position on the clamping component (6).

4. The carbon head conveying and spraying cleaning system according to claim 3, characterized in that, The shifting component (8) also includes a second support arm (84), the free end of which is equipped with a cleaning component (9), and the second support arm (84) and the first support arm (83) are on the same horizontal straight line.

5. The carbon head conveying and spraying cleaning system according to claim 1, characterized in that, A particle generator (96) is provided between the outlet end of the primary cooler (92) and the nozzle (97). The particle generator (96) includes a main body (961). The main body (961) has an expansion section 1 (962), an expansion section 2 (963), and a generation chamber (964) arranged sequentially from bottom to top. The cone angle of the expansion section 1 (962) is twice that of the expansion section 2 (963). The generation chamber (964) is cylindrical and has the same width as the widest part of the expansion section 2 (963). A converging section (971) is provided on the inner wall of the connection between the nozzle (97) and the generation chamber (964). The cone angle of the converging section (971) is no greater than three degrees. The diameter reduction chamber (926) is connected to the inlet end of the expansion section 1 (962).

6. The carbon head conveying and spraying cleaning system according to claim 1, characterized in that, The clamping member (6) includes a ring array of drive cylinders (62). The extension line of the extension direction of the drive cylinders (62) intersects the center line of the silicon rod (1). The end of the drive cylinder (62) is provided with a moving frame (61). The moving frame (61) is provided with a quartz contact piece (611) on the side facing the silicon rod (1).

7. The carbon head conveying and jet cleaning system according to claim 6, characterized in that, The conveying mechanism (3) also includes a baffle (34), which is placed at both ends of the silicon rod (1) parallel to the travel direction of the quartz chain plate (31). A horizontally extending partition block (33) is installed on the middle section of the baffle (34) facing the quartz chain plate (31).

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