Raw material shearing type mixing equipment for single crystal production and use method

Abstract

The invention relates to the technical field of shearing mixing, in particular to raw material shearing type mixing equipment for single crystal production and a using method, the raw material shearing type mixing equipment comprises a barrel, a sealing device is fixed at the upper end of the barrel, a vacuum feeding port is formed in the upper end of the sealing device, and a stirring assembly is fixed at the center position of the upper end of the sealing device; the tail end of a main shaft of the driving motor penetrates through the sealing device to be fixedly provided with a stirring shaft, downward spiral blades, a mixing assembly and upward spiral blades are fixed to the outer side of the stirring shaft, the mixing assembly comprises a stirring bin, a rotating device is rotationally arranged on the inner side of the stirring bin, and a sealing bin is rotationally arranged on one side of the rotating device; a connecting hole is formed in the outer side of the sealing bin, and a driving bevel gear is rotationally connected to the bottom of the inner side of the sealing bin. By arranging the stirring assembly, the layering situation of heavy material sedimentation and light material floating of traditional equipment is broken through, the mixing uniformity of silicon powder and a doping agent is ensured, and the electrical property and structural integrity of a single crystal are ensured.

Description

Technical Field

[0001] This invention relates to the field of shear mixing technology, specifically to a shear mixing device and method for raw materials in single crystal production. Background Technology

[0002] The shear-type mixing equipment for single crystal production raw materials is a mechanical device specifically designed for the efficient and uniform mixing of high-purity raw materials before the production of single crystal materials such as single crystal silicon. It uses mechanical shearing force to quickly mix various raw materials (such as silicon powder, dopants, etc.) into a uniform mixture that meets the requirements for single crystal growth.

[0003] The core of shear mixing equipment is to generate strong shearing force, friction force and impact force in the material through the relative motion between the high-speed rotating part (rotor) and the stationary part (stator), so as to achieve three major functions: strong stirring to uniformly disperse powder materials, break up material agglomerates, restore the original particle size and reduce particle size, and improve the uniformity of the mixture;

[0004] In the raw material preparation stage of single crystal production, the uniformity of mixing silicon powder with dopants such as boron powder and phosphorus powder directly determines the quality of single crystal. The significant density difference between the two has become a technical pain point that is difficult to overcome in shear mixing equipment. The density of silicon powder is about 2.33 g / cm³, while the densities of boron powder and phosphorus powder are 2.34 g / cm³ and 1.82 g / cm³, respectively. Seemingly similar values ​​will cause obvious stratification in the dynamic environment of shear mixing.

[0005] Shear mixing relies on the shear force generated by the equipment to break up the material and promote its diffusion. However, the effect of this force varies for materials with different densities and cannot counteract the effect of gravity on the material. During the mixing process, boron powder with a relatively high density is easily pulled by gravity to break through the shear force constraint and settle and accumulate at the bottom of the equipment. Phosphorus powder with a lower density, due to its weaker inertia, is difficult to move synchronously with silicon powder and is more likely to float upward with the airflow or shear flow, forming top enrichment. This imbalance between settling and floating can lead to local dopant excess or deficiency in the mixed material. During subsequent single crystal growth, a uniform doping distribution cannot be formed, which directly affects the electrical properties and structural integrity of the single crystal.

[0006] Therefore, in response to the above problems, a shear-type mixing device for raw materials in single crystal production and its usage method are proposed. Summary of the Invention

[0007] The purpose of this invention is to provide a shear-type mixing device and method for raw materials in single crystal production, so as to solve the problems mentioned in the background art.

[0008] To achieve the above objectives, the present invention provides the following technical solution:

[0009] A shear-type mixing device for raw materials in single crystal production and its usage method are disclosed. The device includes a cylindrical body with a sealing device fixed to its upper end. A vacuum inlet is provided at the upper end of the sealing device. A stirring assembly is fixed at the center of the upper end of the sealing device. The stirring assembly includes a drive motor, with a stirring shaft fixed to the end of the drive motor's main shaft passing through the sealing device. A downward spiral blade, a mixing component, and an upward spiral blade are fixed to the outside of the stirring shaft. The mixing assembly includes a mixing chamber, with a rotating device rotatably mounted inside the mixing chamber. A sealing chamber rotatably mounted on one side of the rotating device. The sealing chamber has a connecting hole on its outer side, and a drive bevel gear is rotatably connected to the bottom of the inner side of the sealing chamber. The inner center of the drive bevel gear is fixedly connected to the outer side of the middle section of the stirring shaft. A discharge pipe is fixedly fixed to the bottom of the inner side of the stirring chamber, and a discharge valve is fixedly fixed to the lower end of the discharge pipe. The rotating device includes a rotating shaft, a driven bevel gear is fixedly connected to one end of the rotating shaft through the connecting hole, a stirring wheel is fixedly connected to the outer side of the rotating shaft, a fixed rod is fixedly fixed to the outer side of the stirring wheel, and a gravity stirring plate is rotatably connected to the outer side of the fixed rod. The driven bevel gear is meshed with the drive bevel gear.

[0010] As a further optimization of the present invention, the discharge pipe includes a pipe body, guide plates are fixed to the inner sides of the upper and lower ends of the pipe body, and an inclined plate is fixed to the inner side of the inclined pipe position of the pipe body.

[0011] As a further optimization of the present invention, the downward spiral blade, the mixing component and the upward spiral blade on the outer side of the stirring shaft are distributed sequentially along the axial direction of the stirring shaft, the spiral direction of the downward spiral blade is clockwise and the spiral direction of the upward spiral blade is counterclockwise.

[0012] As a further optimization of the present invention, the shape of the vertical cross section of the cylinder is set to trapezoidal, and the gap between the blade edge of the downward spiral blade and the inner wall of the cylinder is the same as the gap between the blade edge of the upward spiral blade and the inner wall of the cylinder.

[0013] As a further optimization of the present invention, the stirring chamber is in the form of a ring structure, and four rotating devices are provided. The four rotating devices are evenly distributed circumferentially around the axis of the sealing chamber, and the outer side of the middle section of the stirring shaft is rotatably connected to the sealing chamber.

[0014] As a further optimization of the present invention, four connecting holes are provided, and the four connecting holes are evenly distributed circumferentially around the axis of the sealing chamber. The inner diameter of each connecting hole is adapted to the outer diameter of the rotating shaft, and the rotating shaft is connected to the driven bevel gear after passing through the connecting hole.

[0015] As a further optimization of the present invention, the stirring wheel has a cylindrical structure, and there are multiple fixing rods. The multiple fixing rods are evenly distributed circumferentially around the axis of the rotation shaft. Each fixing rod corresponds to a number and position of each gravity stirring plate. The gravity stirring plate has an L-shaped structure.

[0016] As a further optimization of the present invention, the number of teeth of the driving bevel gear is the same as the number of teeth of the driven bevel gear, the pitch circle diameter of the driving bevel gear is the same as the pitch circle diameter of the driven bevel gear, and the axis of the driving bevel gear intersects the axis of the driven bevel gear perpendicularly.

[0017] As a further optimization of the present invention, the middle section of the tube body is an inclined tube structure, the guide plates on the inner sides of the upper and lower ends of the tube body form an angle of 60° with the tube body, three inclined plates are provided, the three inclined plates are distributed in parallel, the length of the inclined plate is consistent with the length of the inclined tube section of the tube body, and the inclination direction of the inclined plate is consistent with the extension direction of the inclined tube section of the tube body.

[0018] A method for using a shear-type mixing device for raw materials in single crystal production:

[0019] S1: Check that there are no impurities remaining on the inner wall of the cylinder and the sealing device, and that there are no scratches on the mirror polished surface. Confirm that the vacuum feed port sealing gasket is intact and the discharge valve is in the closed state. Introduce high-purity nitrogen into the equipment to replace the air in the chamber. After replacement, maintain a slight positive pressure in the chamber to prevent oxidation. Start the vacuum feeding system and add high-purity silicon powder and dopant through the vacuum feed port according to the ratio. After feeding, close the vacuum feed port to ensure that the sealing device is tightly sealed.

[0020] S2: Start the stirring assembly, drive the motor to drive the stirring shaft to rotate. When the stirring shaft rotates, it synchronously drives the downward spiral blades, mixing assembly, and upward spiral blades that are distributed axially in sequence to rotate. The clockwise spiral downward spiral blades push the upper material downward and towards the bottom of the cylinder, while the counterclockwise spiral upward spiral blades push the bottom material upward and towards the top of the cylinder, forming an axial convection circulation, providing a uniform material base for the mixing assembly.

[0021] S21: The mixing component starts synchronously with the stirring component. When the stirring shaft rotates, it drives the fixed drive bevel gear in the middle section to rotate. The drive bevel gear drives the four driven bevel gears and the corresponding rotating device to rotate through meshing transmission, entering the mixing operation state. The number of teeth and pitch circle diameter of the drive bevel gear and the driven bevel gear are the same, realizing constant speed transmission. It drives the rotating device to rotate and performs radial shear mixing on the material passing through the mixing chamber, breaking the stratification trend caused by density difference. During the mixing process, the material flows to the mixing chamber through the downward spiral blade and the upward spiral blade. After being fully mixed by the rotating device, it can form a uniform material agglomerate in the chamber, avoiding stratification.

[0022] S22: When the stirring wheel rotates at high speed, it drives the outer fixed rod and gravity stirring plate to rotate synchronously; when the L-shaped gravity stirring plate rotates with the stirring wheel, it maintains the posture of adhering to the material under the action of gravity, gently shears the silicon powder and dopants that pass through, breaks up the material agglomerates, and at the same time drives the light and heavy materials to fully penetrate and blend. The four circumferentially evenly distributed rotating devices work synchronously to achieve all-round shearing and mixing of materials in the mixing chamber without dead angles.

[0023] S3: After mixing is completed and the uniform material distribution of the equipment is finished, open the discharge valve and the uniform material in the mixing chamber is discharged at a uniform speed through the discharge pipe. During the discharge process, the mixing components continue to rotate with the mixing shaft to ensure that there is no material residue or sedimentation stratification in the mixing chamber.

[0024] S4: Open the discharge valve. The uniform material in the mixing chamber flows into the upper part of the discharge pipe. The upper guide plate guides the material to flow smoothly downward at a 60° angle, avoiding splashing or settling caused by the material impacting the pipe. When the material flows into the inclined section in the middle of the pipe, three parallel inclined plates divert and guide the material to ensure that the material flows at a uniform speed along the inclined pipe, preventing the sedimentation of high-density dopants and the floating of low-density silicon powder, and eliminating secondary stratification during the unloading process. After being guided again by the lower guide plate, the material is discharged at a uniform speed from the discharge valve, completing the unloading.

[0025] Compared with the prior art, the beneficial effects of the present invention are:

[0026] 1. In this invention, by setting the downward spiral blade, mixing component, and upward spiral blade in the stirring component and combining them with the radial rotation device of the bevel gear drive in the mixing component, a three-dimensional mixing system is constructed, which breaks the stratification of heavy material settling and light material floating in traditional equipment, ensuring the uniformity of silicon powder and dopant mixing, and ensuring the electrical performance and structural integrity of the single crystal.

[0027] 2. In this invention, the bevel gear transmission mechanism is completely isolated from the material area by the set sealing chamber structure. With the precise matching and sealing of the connecting hole and the rotating shaft, it not only prevents the material from entering the transmission area and causing jamming and wear, but also avoids the contamination of high-purity raw materials by lubricating oil, metal shavings and other contaminants.

[0028] 3. In this invention, the gravity stirring plate is adaptively adjusted in posture by gravity and material resistance to achieve low-intensity gentle shearing, which can effectively disperse the agglomerates of silicon powder and dopants, and avoid strong impacts that damage the crystal structure.

[0029] 4. In this invention, by optimizing the design of the guide plate angle and the inclined plate structure, the material flow rate and stability are taken into account, the sedimentation rate of high-density dopants and the floating rate of low-density silicon powder are slowed down, and the unloading process is completed without secondary stratification, ensuring the uniformity and consistency of the discharged material. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0031] Figure 2 This is a schematic diagram of the cross-sectional structure of the cylindrical body of the present invention;

[0032] Figure 3 This is a schematic diagram of the upward spiral blade mounting position structure of the present invention;

[0033] Figure 4 This is a schematic diagram of the cross-sectional structure of the mixing chamber of the present invention;

[0034] Figure 5 This is a schematic diagram of the cross-sectional structure of the sealing chamber of the present invention;

[0035] Figure 6 This is a schematic diagram of the connection hole mounting position structure of the present invention;

[0036] Figure 7 This is a schematic diagram of the overall structure of the rotating device of the present invention;

[0037] Figure 8 This is a schematic diagram of the mounting position of the fixing rod in this invention;

[0038] Figure 9 This is a schematic diagram of the cross-sectional structure of the tube body of the present invention.

[0039] In the diagram: 1. Cylinder; 2. Sealing device; 3. Vacuum feed inlet;

[0040] 4. Stirring assembly; 41. Drive motor; 42. Stirring shaft; 43. Downward spiral blades;

[0041] 44. Mixing components; 441. Mixing chamber;

[0042] 442. Rotating device; 4421. Rotating shaft; 4422. Driven bevel gear; 4423. Stirring wheel; 4424. Fixed rod; 4425. Gravity stirring plate;

[0043] 443. Sealed chamber; 444. Connecting hole; 445. Drive bevel gear;

[0044] 446. Discharge pipe; 4461. Pipe body; 4462. Guide plate; 4463. Inclined plate;

[0045] 447. Discharge valve; 45. Upward spiral blade. Detailed Implementation

[0046] Please see Figures 1-9 The present invention provides a technical solution:

[0047] A shear-type mixing device for raw materials in single crystal production and its usage method include a cylindrical body 1, a sealing device 2 fixed at the upper end of the cylindrical body 1, a vacuum feed port 3 at the upper end of the sealing device 2, and a stirring assembly 4 fixed at the center of the upper end of the sealing device 2. The stirring assembly 4 includes a drive motor 41, with a stirring shaft 42 fixed to the end of the drive motor 41 through the sealing device 2. A downward spiral blade 43, a mixing assembly 44, and an upward spiral blade 45 are fixed to the outside of the stirring shaft 42. The mixing assembly 44 includes a mixing chamber 441, a rotating device 442 rotating inside the mixing chamber 441, and a sealing chamber 443 rotating on one side of the rotating device 442. A connection hole 44 is provided on the outside of the sealing chamber 443. 4. A drive bevel gear 445 is rotatably connected to the bottom inner side of the sealed chamber 443. The inner center of the drive bevel gear 445 is fixedly connected to the outer side of the middle section of the stirring shaft 42. A discharge pipe 446 is fixedly fixed to the bottom inner side of the stirring chamber 441. A discharge valve 447 is fixedly fixed to the lower end of the discharge pipe 446. The rotating device 442 includes a rotating shaft 4421. A driven bevel gear 4422 is fixedly connected to a section of the rotating shaft 4421 through the connecting hole 444. A stirring wheel 4423 is fixedly connected to the outer side of the rotating shaft 4421. A fixing rod 4424 is fixedly fixed to the outer side of the stirring wheel 4423. A gravity stirring plate 4425 is rotatably connected to the outer side of the fixing rod 4424. The driven bevel gear 4422 is meshed with the drive bevel gear 445.

[0048] The downward spiral blade 43, the mixing component 44, and the upward spiral blade 45 on the outside of the stirring shaft 42 are distributed sequentially along the axial direction of the stirring shaft 42. The spiral direction of the downward spiral blade 43 is clockwise, and the spiral direction of the upward spiral blade 45 is counterclockwise. The reverse design of the downward spiral blade 43 (clockwise) and the upward spiral blade 45 (counterclockwise) enhances the axial convection circulation efficiency. The upper light material is pushed downward and the lower heavy material is pulled upward, forming a closed-loop flow and providing a uniform material base for the mixing component 44.

[0049] The vertical cross-section of the cylinder 1 is set to be trapezoidal. The gap between the blade edge of the downward spiral blade 43 and the inner wall of the cylinder 1 is the same as the gap between the blade edge of the upward spiral blade 45 and the inner wall of the cylinder 1. The trapezoidal cylinder 1 is adapted to the pushing trajectory of the spiral blades, increasing the material contact area. The gaps between the downward spiral blade 43 and the upward spiral blade 45 and the inner wall of the cylinder 1 are consistent, ensuring that the material pushing force in each area is uniform and avoiding local material accumulation.

[0050] The mixing chamber 441 has a circular structure, and four rotating devices 442 are provided. The four rotating devices 442 are evenly distributed circumferentially around the axis of the sealed chamber 443. The outer side of the middle section of the stirring shaft 42 is rotatably connected to the sealed chamber 443. The circular mixing chamber 441 is adapted to the structure of the cylinder 1. The four rotating devices 442 are evenly distributed circumferentially to achieve all-round shearing and mixing of materials in the mixing chamber 441 without dead angles. The rotatable connection between the stirring shaft 42 and the sealed chamber 443 ensures the stability of the transmission.

[0051] There are four connecting holes 444, which are evenly distributed circumferentially around the axis of the sealing chamber 443. The inner diameter of each connecting hole 444 is adapted to the outer diameter of the rotating shaft 4421. After passing through the connecting hole 444, the rotating shaft 4421 is connected to the driven bevel gear 4422. The four connecting holes 444 correspond one-to-one with the rotating device 442, and the inner diameter is precisely adapted to the outer diameter of the rotating shaft 4421, ensuring that the rotating shaft 4421 runs smoothly without shaking. At the same time, it reduces the risk of material leakage from the connecting hole 444 to the sealing chamber 443 and ensures the cleanliness of the internal transmission mechanism.

[0052] The stirring wheel 4423 has a cylindrical structure, and multiple fixing rods 4424 are provided. The multiple fixing rods 4424 are evenly distributed circumferentially around the axis of the rotating shaft 4421. Each fixing rod 4424 corresponds to the number and position of each gravity stirring plate 4425. The gravity stirring plate 4425 has an L-shaped structure. The cylindrical stirring wheel 4423, together with the evenly distributed fixing rods 4424, increases the material shear coverage. The L-shaped gravity stirring plate 4425 can adapt to the material resistance and adjust its posture to achieve gentle shearing.

[0053] The number of teeth of the driving bevel gear 445 is the same as that of the driven bevel gear 4422. The pitch circle diameter of the driving bevel gear 445 is the same as that of the driven bevel gear 4422. The axis of the driving bevel gear 445 intersects the axis of the driven bevel gear 4422 perpendicularly. The number of teeth and the pitch circle diameter of the driving bevel gear 445 and the driven bevel gear 4422 are the same, so as to achieve constant speed vertical transmission, ensure that the speed of the four rotating devices 442 is synchronized, and avoid mixing differences caused by uneven local shear strength.

[0054] The discharge pipe 446 includes a pipe body 4461, with guide plates 4462 fixed to the inner sides of the upper and lower ends of the pipe body 4461, and inclined plates 4463 fixed to the inner side of the inclined pipe section of the pipe body 4461. The 60° guide plates 4462 at the upper and lower ends of the pipe body 4461 guide the material to flow smoothly and avoid impact settling. The three parallel inclined plates 4463 in the inclined pipe section realize the diversion and guidance of the material, delay the secondary stratification caused by density difference during the unloading process, and improve the uniformity of the unloading flow rate.

[0055] The middle section of the pipe body 4461 is an inclined tube structure. The guide plates 4462 on the inner sides of the upper and lower ends of the pipe body 4461 form an angle of 60° with the pipe body 4461. There are three inclined plates 4463, which are distributed in parallel. The length of the inclined plates 4463 is the same as the length of the inclined tube section of the pipe body 4461, and the inclination direction of the inclined plates 4463 is the same as the extension direction of the inclined tube section of the pipe body 4461. The inclined plates 4463 can maximize the diversion and guiding effect, completely eliminate the stratification of unloading. The 60° angle of the guide plates 4462 takes into account the material flow rate and stability, avoiding material accumulation caused by too slow flow rate and preventing stratification caused by too fast flow rate, further improving the material uniformity during the unloading process.

[0056] Work process: Check that there are no impurities on the inner wall of cylinder 1 and sealing device 2, and that there are no scratches on the mirror polished surface. Confirm that the sealing gasket of vacuum feed port 3 is intact and that the discharge valve 447 is in the closed state. Introduce high-purity nitrogen into the equipment to replace the air in the chamber. After replacement, maintain a slight positive pressure in the chamber to prevent oxidation. Start the vacuum feeding system and add high-purity silicon powder and dopant through vacuum feed port 3 according to the ratio. After feeding, close vacuum feed port 3 to ensure that sealing device 2 is tightly sealed.

[0057] When the stirring assembly 4 is started, the drive motor 41 drives the stirring shaft 42 to rotate. When the stirring shaft 42 rotates, it synchronously drives the downward spiral blades 43, the mixing assembly 44, and the upward spiral blades 45, which are distributed axially in sequence, to rotate. The clockwise spiral downward spiral blades 43 push the upper material downward and towards the bottom of the cylinder 1, while the counterclockwise spiral upward spiral blades 45 push the bottom material upward and towards the top of the cylinder 1, forming an axial convection circulation, providing a uniform material base for the mixing assembly 44, and realizing the initial convergence of light and heavy materials.

[0058] The mixing component 44 starts synchronously with the stirring component 4. When the stirring shaft 42 rotates, it drives the fixed drive bevel gear 445 in the middle section to rotate. The drive bevel gear 445 drives the four driven bevel gears 4422 and the corresponding rotating device 442 to rotate through meshing transmission, and enters the mixing operation state. The number of teeth and pitch circle diameter of the drive bevel gear 445 and the driven bevel gear 4422 are the same, so as to achieve constant speed transmission and drive the rotating device 442 to rotate. The material passing through the mixing chamber 441 is radially sheared and mixed to break the stratification trend caused by density difference. During the mixing process, the material is convected to the mixing chamber 441 through the downward spiral blade 43 and the upward spiral blade 45. After being fully mixed by the rotating device 442, a uniform material agglomerate can be formed in the chamber to avoid stratification.

[0059] When the stirring wheel 4423 rotates at high speed, it drives the outer fixed rod 4424 and the gravity stirring plate 4425 to rotate synchronously. When the L-shaped gravity stirring plate 4425 rotates with the stirring wheel 4423, it maintains the posture of adhering to the material under the action of gravity, gently shears the silicon powder and dopants that pass through, breaks up the material agglomerates, and at the same time drives the light and heavy materials to fully interweave and blend. The four circumferentially evenly distributed rotating devices 442 work synchronously to achieve all-round shearing and mixing of materials in the mixing chamber 441 without dead angles.

[0060] After mixing is completed and the uniform material distribution is finished, the discharge valve 447 is opened, and the uniform material in the mixing chamber 441 is discharged at a uniform speed through the discharge pipe 446. During the discharge process, the mixing component 44 continues to rotate with the mixing shaft 42 to ensure that there is no material residue or sedimentation stratification in the mixing chamber 441.

[0061] When the discharge valve 447 is opened, the uniform material in the mixing chamber 441 flows into the upper end of the pipe body 4461 of the discharge pipe 446. The upper guide plate 4462 guides the material to flow smoothly downward at a 60° angle, avoiding splashing or settling caused by the material impacting the pipe body 4461. When the material flows into the inclined section in the middle of the pipe body 4461, three parallel inclined plates 4463 divert and guide the material to ensure that the material flows at a uniform speed along the inclined pipe, preventing the sedimentation of high-density dopants and the floating of low-density silicon powder, and eliminating secondary stratification during the unloading process. After being guided again by the lower guide plate 4462, the material is discharged at a uniform speed from the discharge valve 447, completing the unloading.

[0062] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only for the purpose of helping to understand the method and core ideas of the present invention. The above descriptions are only preferred embodiments of the present invention. It should be noted that due to the limitations of textual expression, while there are objectively infinite specific structures, those skilled in the art can make several improvements, modifications, or changes without departing from the principles of the present invention, and can also combine the above technical features in an appropriate manner. These improvements, modifications, changes, or combinations, or the direct application of the inventive concept and technical solution to other situations without modification, should all be considered within the scope of protection of the present invention.

Claims

1. A shear-type mixing device for raw materials in single crystal production, comprising a cylindrical body (1), characterized in that: A sealing device (2) is fixed at the upper end of the cylinder (1), and a vacuum feed port (3) is opened at the upper end of the sealing device (2). A stirring assembly (4) is fixed at the center of the upper end of the sealing device (2). The stirring assembly (4) includes a drive motor (41), the end of the main shaft of the drive motor (41) passes through the sealing device (2) and is fixed to a stirring shaft (42). A downward spiral blade (43), a mixing assembly (44) and an upward spiral blade (45) are fixed on the outside of the stirring shaft (42). The mixing assembly (44) includes a stirring chamber (441), a rotating device (442) is rotatably mounted inside the stirring chamber (441), and a sealing chamber (443) is rotatably mounted on one side of the rotating device (442). A connecting hole (444) is provided on the outside of the sealing chamber (443). A drive bevel gear (445) is rotatably connected to the bottom inside the sealing chamber (443). The center of the drive bevel gear (445) is fixedly connected to the outer side of the middle section of the stirring shaft (42). A discharge pipe (446) is fixed to the bottom inside the stirring chamber (441), and a discharge valve (447) is fixed to the lower end of the discharge pipe (446). The rotating device (442) includes a rotating shaft (4421), a driven bevel gear (4422) is fixedly connected to a section of the rotating shaft (4421) through a connecting hole (444), a stirring wheel (4423) is fixedly connected to the outside of the rotating shaft (4421), a fixing rod (4424) is fixedly fixed to the outside of the stirring wheel (4423), a gravity stirring plate (4425) is rotatably connected to the outside of the fixing rod (4424), and the driven bevel gear (4422) is meshed with the driving bevel gear (445).

2. The raw material shear mixing equipment for single crystal production according to claim 1, characterized in that: The discharge pipe (446) includes a pipe body (4461), and guide plates (4462) are fixed on the inner sides of the upper and lower ends of the pipe body (4461). An inclined plate (4463) is fixed on the inner side of the inclined pipe position of the pipe body (4461).

3. The raw material shear mixing equipment for single crystal production according to claim 1, characterized in that: The downward spiral blade (43), mixing component (44) and upward spiral blade (45) on the outside of the stirring shaft (42) are distributed sequentially along the axial direction of the stirring shaft (42). The spiral direction of the downward spiral blade (43) is clockwise, and the spiral direction of the upward spiral blade (45) is counterclockwise.

4. The raw material shear mixing equipment for single crystal production according to claim 1, characterized in that: The vertical cross-section of the cylinder (1) is set to be trapezoidal, and the gap between the blade edge of the downward spiral blade (43) and the inner wall of the cylinder (1) is the same as the gap between the blade edge of the upward spiral blade (45) and the inner wall of the cylinder (1).

5. The raw material shear mixing equipment for single crystal production according to claim 1, characterized in that: The stirring chamber (441) has a circular structure, and four rotating devices (442) are provided. The four rotating devices (442) are evenly distributed circumferentially around the axis of the sealing chamber (443). The outer side of the middle section of the stirring shaft (42) is rotatably connected to the sealing chamber (443).

6. The raw material shear mixing equipment for single crystal production according to claim 1, characterized in that: There are four connecting holes (444). The four connecting holes (444) are evenly distributed circumferentially around the axis of the sealing chamber (443). The inner diameter of each connecting hole (444) is adapted to the outer diameter of the rotating shaft (4421). The rotating shaft (4421) passes through the connecting hole (444) and is connected to the driven bevel gear (4422).

7. The raw material shear mixing equipment for single crystal production according to claim 1, characterized in that: The stirring wheel (4423) has a cylindrical structure, and there are multiple fixing rods (4424). The multiple fixing rods (4424) are evenly distributed circumferentially around the axis of the rotating shaft (4421). Each fixing rod (4424) corresponds to the number and position of each gravity stirring plate (4425). The gravity stirring plate (4425) has an L-shaped structure.

8. The raw material shear mixing equipment for single crystal production according to claim 1, characterized in that: The number of teeth of the driving bevel gear (445) is the same as the number of teeth of the driven bevel gear (4422). The pitch circle diameter of the driving bevel gear (445) is the same as the pitch circle diameter of the driven bevel gear (4422). The axis of the driving bevel gear (445) intersects the axis of the driven bevel gear (4422) perpendicularly.

9. The raw material shear mixing equipment for single crystal production according to claim 2, characterized in that: The middle section of the tube body (4461) is an inclined tube structure. The guide plates (4462) on the inner sides of the upper and lower ends of the tube body (4461) form an angle of 60° with the tube body (4461). There are three inclined plates (4463) arranged in parallel. The length of the inclined plate (4463) is the same as the length of the inclined tube section of the tube body (4461). The inclination direction of the inclined plate (4463) is the same as the extension direction of the inclined tube section of the tube body (4461).

10. A method of using a raw material shear mixing device for single crystal production according to any one of claims 1-9, characterized in that: S1: Check that there are no impurities on the inner wall of the cylinder (1) and the sealing device (2), and that there are no scratches on the mirror polished surface. Confirm that the sealing gasket of the vacuum feed port (3) is intact and that the discharge valve (447) is closed. Introduce high-purity nitrogen into the equipment to replace the air in the chamber. After the replacement is completed, maintain a slight positive pressure in the chamber to prevent oxidation. Start the vacuum feeding system and add high-purity silicon powder and dopant through the vacuum feed port (3) according to the ratio. After the feeding is completed, close the vacuum feed port (3) to ensure that the sealing device (2) is tightly sealed. S2: Start the stirring assembly (4), drive the motor (41) to drive the stirring shaft (42) to rotate. When the stirring shaft (42) rotates, it synchronously drives the downward spiral blades (43), mixing assembly (44), and upward spiral blades (45) distributed in sequence along the axis to rotate. The clockwise spiral downward spiral blades (43) push the upper material downward and flow to the bottom of the cylinder (1), while the counterclockwise spiral upward spiral blades (45) push the bottom material upward and flow to the top of the cylinder (1), forming an axial convection circulation, providing a uniform material base for the mixing assembly (44); S21: The mixing component (44) starts synchronously with the stirring component (4). When the stirring shaft (42) is running, it drives the fixed driving bevel gear (445) in the middle section to rotate. The driving bevel gear (445) drives the four driven bevel gears (4422) and the corresponding rotating device (442) to run through meshing transmission, and enters the mixing operation state. The number of teeth and pitch circle diameter of the driving bevel gear (445) and the driven bevel gear (4422) are the same, realizing constant speed transmission, driving the rotating device (442) to rotate, and performing radial shear mixing on the material passing through the mixing chamber (441), breaking the stratification trend caused by density difference. During the mixing process, the material flows to the mixing chamber (441) through the downward spiral blade (43) and the upward spiral blade (45). After being fully mixed by the rotating device (442), a uniform material agglomerate can be formed in the chamber, avoiding stratification. S22: When the stirring wheel (4423) rotates at high speed, it drives the outer fixed rod (4424) and the gravity stirring plate (4425) to rotate synchronously; when the L-shaped gravity stirring plate (4425) rotates with the stirring wheel (4423), it maintains the posture of adhering to the material under the action of gravity, gently shears the silicon powder and dopants that pass through, breaks up the material agglomerates, and at the same time drives the light and heavy materials to fully interweave and blend. The four circumferentially evenly distributed rotating devices (442) work synchronously to realize the all-round shearing and mixing of materials in the mixing chamber (441) without dead angles. S3: After mixing is completed, as the equipment finishes uniform material distribution, open the discharge valve (447), and the uniform material in the mixing chamber (441) is discharged at a uniform speed through the discharge pipe (446). During the discharge process, the mixing component (44) continues to operate with the mixing shaft (42) to ensure that there is no material residue or sedimentation stratification in the mixing chamber (441). S4: Open the discharge valve (447), and the uniform material in the mixing chamber (441) flows into the upper end of the pipe body (4461) of the discharge pipe (446). The upper guide plate (4462) guides the material to flow smoothly downward at a 60° angle, avoiding the material from impacting the pipe body (4461) and causing splashing or settling. When the material flows into the inclined pipe section in the middle of the pipe body (4461), three parallel inclined plates (4463) divert and guide the material to ensure that the material flows at a uniform speed along the inclined pipe, preventing the high-density dopants from settling and the low-density silicon powder from floating, and eliminating secondary stratification during the unloading process. After being guided again by the lower guide plate (4462), the material is discharged at a uniform speed from the discharge valve (447) to complete the unloading.

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