Cyclone type multi-stage powder selecting mechanism suitable for ultrafine powder

Abstract

The utility model relates to the technical field of material sorting, in particular to a cyclone type multistage powder sorting mechanism suitable for ultrafine powder, which comprises a shell and a sorting mechanism, the shell comprises an outer cylinder and an inner cylinder, the sorting mechanism is arranged below the inner cylinder, and the sorting mechanism comprises a rotor device, a driving device and a sealing device; the sealing device comprises a sealing ring, a graphite packing and an atmosphere connecting pipe, the graphite packing is arranged in a steel plate groove in the top of the rotor device, the inner wall of the inner cylinder is connected with the sealing ring, and the sealing ring compresses the graphite packing to form hard sealing; the atmosphere connecting pipe is arranged between the outer wall of the inner barrel and the inner wall of the outer barrel to play a role in air sealing, under the condition of double sealing, the powder selecting machine can enable the powder screening fineness to be accurate to be below 20 micrometers, the quality of fine powder finished products obtained through screening can reach 97% or above, the quality of the finished products is remarkably improved, and the production cost is reduced. The problem of fine powder leakage prevention sealing in a traditional powder concentrator is successfully solved, and the overall performance of the powder concentrator is improved.

Description

Technical Field

[0001] This utility model relates to the field of material sorting technology, and in particular to a cyclone-type multi-stage powder sorting mechanism suitable for ultrafine powders. Background Technology

[0002] Ultrafine powders, due to their fine particle size, narrow distribution, uniform quality, large specific surface area, high surface activity, fast chemical reaction rate, and high sintered body strength, are widely used in various fields such as electronics, pharmaceuticals, pesticides, military, chemicals, light industry, environmental protection, and mold making. However, the production technology of ultrafine powders is highly complex, resulting in high product prices. Currently, the sorting of ultrafine powders in China mostly uses traditional sorting equipment, such as the Sepax type from Denmark and the O-Sepa type vortex classifier from Japan. While these devices can meet the sorting requirements for 80μm fineness to a certain extent, they have significant shortcomings when processing ultrafine powders below 20μm, especially in terms of sealing to prevent material loss. Due to the excessively high fineness of the finished product, traditional equipment struggles to effectively recover ultrafine powders, leading to low production efficiency.

[0003] To address the aforementioned issues, there is an urgent need for a novel cyclone-type dynamic powder sorting mechanism to solve the sealing and recovery problems in ultrafine powder sorting devices, thereby meeting the high-precision requirements for ultrafine powder sorting in production. This mechanism has significant application value and market prospects. Utility Model Content

[0004] To address the problems mentioned in the background section and overcome the aforementioned shortcomings, this utility model provides the following technical solution:

[0005] A cyclone-type multi-stage powder classifier suitable for ultrafine powder includes a shell and a sorting mechanism. Specifically, the shell consists of an inner cylinder and an outer cylinder, with the outer cylinder located outside the inner cylinder. The sorting mechanism is located below the inner cylinder. The top of the sorting mechanism is a rotor device, the bottom is a drive device, and a sealing device is also included. The drive device is powered by a working chamber motor. Through the above devices, the raw powder entering the shell is sieved into coarse powder and fine powder. The sieved coarse powder and fine powder are collected through their respective collection paths.

[0006] The sealing device consists of two parts: a sealing ring, a graphite packing, and an atmospheric connection pipe, forming a hard seal and an atmospheric seal. The hard seal is set in two steel plate grooves on the upper end face of the rotor device, and a graphite packing is set in the steel plate grooves. The inner wall of the inner cylinder is connected to the sealing ring, which presses the graphite packing to form a hard seal. At the same time, several atmospheric connections pipes are radially and evenly welded between the outer wall of the inner cylinder and the inner wall of the outer cylinder. On the one hand, the atmospheric connections pipes can position and support the inner cylinder. On the other hand, the atmospheric connections pipes connect the cavity between the bottom of the inner wall of the inner cylinder and the sealing ring to the external atmosphere of the outer cylinder. Since there is always an airflow carrying the finished fine powder in the inner cylinder, it is under positive pressure relative to the external atmosphere. The atmosphere is supplied to the cavity between the bottom of the inner wall of the inner cylinder and the sealing ring through the atmospheric connections pipes to form an atmospheric seal, preventing the finished fine powder from escaping from the inner cylinder due to wear of the graphite packing or the sealing ring.

[0007] Furthermore, the sealing ring is a "Z"-shaped sealing ring;

[0008] Furthermore, the atmospheric inlet pipe is at an angle of 10° to the horizontal direction to prevent fine powder from entering the atmospheric inlet pipe in the event of occasional airflow instability.

[0009] The rotor device consists of a rotor, a drive shaft, and a tie rod device; several rotor blades of the same shape are welded on the outer ring of the rotor. Driven by the drive shaft and tie rod device, the vortex field formed by the rotating rotor blades is used to screen the raw powder.

[0010] Furthermore, the rotor is inverted conical, and the angle between the rotor's hypotenuse and the vertical centerline of the high-sealing cyclone dynamic classifier is 8 to 15 degrees. The inverted conical rotor can make the linear velocities of the axial moving blades different, thereby enabling precise sorting based on the particle size differences of the raw powder and expanding the extreme range of the finished fine powder.

[0011] Furthermore, the nominal diameter of the rotor is defined as the diameter of the axial middle section of the rotor, the rotor height is 0.5 to 0.55 of the nominal diameter, and the linear velocity of the nominal diameter section when the rotor is running is 25 to 40 m / s;

[0012] Furthermore, the vertical cross-section of the rotor blades is a parallelogram, the width of the rotor blades is 60-70mm, each rotor blade is inclined at 15-20° in the vertical direction of the high-sealing cyclone dynamic classifier, and the minimum distance between adjacent rotor blades is 35-40mm.

[0013] The outer cylinder consists of a feed inlet, a volute, and a lower cone. The diameter of the outer cylinder is twice the diameter of the inner cylinder, and the diameter of the inner cylinder is the same as the maximum diameter of the inverted conical rotor.

[0014] Furthermore, the center point of the volute and the center point of the inner cylinder are offset upwards by 150-300 mm in the vertical direction;

[0015] Furthermore, the lower vertebra is an oblique cone, and the angle between the side of the oblique cone and the axis of rotation does not exceed 40°.

[0016] Compared with the prior art, the beneficial effects of this utility model are:

[0017] 1. This application improves the traditional cyclone classifier, especially by optimizing the traditional sealing device and adopting a dual sealing method that combines hard sealing with air sealing.

[0018] In this application, graphite packing is placed in a steel plate groove at the top of the rotor device, and a sealing ring is set to press it to form a hard seal. An atmospheric pipe is added between the outer wall of the inner cylinder and the inner wall of the outer cylinder, and external air can be supplied to the cavity between the bottom of the inner wall of the inner cylinder and the sealing ring through the atmospheric pipe to form an air seal.

[0019] With double sealing protection, the vortex formed by the rotor rotation and the internal airflow inside the cyclone can efficiently screen powder. Due to the improvement of the sealing device, the performance of the powder classifier is significantly improved. It can not only accurately screen powder with a fineness of less than 20μm, but also adjust the screening fineness to 5μm and below. The quality of the fine powder product obtained by screening can reach more than 97%, and the quality of the finished product is significantly improved. It successfully solves the problems of preventing fine powder from leaking and sealing in traditional powder classifiers, as well as the difficulty in high-quality recovery of fine powder. It not only improves the overall performance of the powder classifier, but also provides a more efficient and reliable solution for the powder processing industry.

[0020] 2. To further improve the sealing performance of the air classifier, the sealing ring is designed in a "Z" shape to reduce the sealing gap of the sealing ring. The atmospheric connection is set at a certain angle with the horizontal direction, which can not only better position and support the inner cylinder, but also prevent fine powder from entering the atmospheric connection and causing waste.

[0021] 3. The inverted conical rotor structure allows the powder to converge more smoothly towards the center under gravity, reducing the accumulation and residue of powder on the rotor surface, thereby improving the flowability and processing efficiency of the material. At the same time, setting the rotor blades to have a certain tilt angle further enhances the centrifugal force and shear force of the powder, enabling the material to be dispersed and classified more efficiently during rotor rotation, thus improving the recovery rate and quality of fine powder.

[0022] 4. The bottom of the outer cylinder mainly collects the coarse material obtained from screening. Setting the lower cone as an inclined cone also reduces the increase in energy consumption and equipment wear caused by material accumulation, significantly improving the overall performance and operating efficiency of the system. Attached Figure Description

[0023] Figure 1This is a schematic diagram of the sealing structure in Example 1;

[0024] Figure 2 This is a schematic cross-sectional view of the overall structure of the high-sealing cyclone dynamic air classifier in Example 2;

[0025] Figure 3 This is a schematic diagram of the housing structure of the high-sealing cyclone dynamic air classifier in Example 2;

[0026] Figure 4 This is a schematic diagram of the sealing structure of the high-sealing cyclone dynamic air classifier in Example 2;

[0027] Figure 5 This is a schematic diagram of the rotor structure of the high-sealing cyclone dynamic air classifier in Example 2;

[0028] Figure 6 This is a schematic diagram of the powder flow path in the high-sealing cyclone dynamic classifier in Example 2.

[0029] 1. Shell 11. Feed Inlet 12. Volute

[0030] 13. Inner cylinder 14, outer cylinder 15, lower vertebral body

[0031] 2. Rotor assembly 21, rotor 211, rotor blades

[0032] 22. Drive shaft; 23. Tie rod assembly; 3. Drive unit

[0033] 4. Sealing device 41, sealing ring 42, graphite packing

[0034] 43. Atmospheric access control A - Fine powder collection route B - Coarse powder collection route Detailed Implementation

[0035] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0036] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0037] Example 1

[0038] like Figure 1As shown in the figure, the "H-type labyrinth" sealing ring 41 commonly used in cyclone dynamic air classifiers is a common type of air classifier. The sealing gap of the "H-type labyrinth" sealing ring 41 is usually 8-10 mm. Therefore, during the screening of raw powder, the sealing effect is acceptable in the classification and screening of powder with a fineness of less than 80 μm. However, when the powder fineness is less than 20 μm, the sealing gap is too large, and the powder continuously circulates in the screening mechanism, making it difficult to be screened out. This will result in a significant decrease in the screening efficiency. Furthermore, due to the poor sealing effect, the fine powder product obtained after screening contains a large amount of coarse powder with a fineness greater than 20 μm, which affects the quality of the finished ultrafine powder.

[0039] Example 2

[0040] Based on Example 1, in order to improve the screening and collection of powder with a fineness of less than 20 μm, the structure of the cyclone dynamic classifier was further adjusted in this application, and the sealing device 4 was improved.

[0041] like Figure 2 The figure shows a cross-sectional schematic diagram of the overall structure of the high-sealing cyclone dynamic air classifier of this application. As shown in the figure, the high-sealing cyclone dynamic air classifier consists of a shell 1 and a sorting mechanism.

[0042] Combination Figure 3 As shown, the housing 1 includes an outer cylinder 14 and an inner cylinder 13. The inner cylinder 13 is located inside the outer cylinder 14. The outer cylinder 14 is also provided with a feed inlet 11, a volute 12, and a lower cone 15, wherein the feed inlet 11 and the volute 12 are located on the upper part of the outer cylinder 14, and the lower cone 15 is the bottom of the outer cylinder 14.

[0043] Furthermore, the lower vertebral body 15 is an oblique cone, such as... Figure 2 As shown in the cross-sectional view, one side of the lower cone 15 is perpendicular to the bottom surface, and the other inclined side forms a certain angle with the vertical direction. The angle formed is less than or equal to 40°. This design can effectively reduce dead corners in the container, facilitate the natural falling of the screened coarse powder in the container, facilitate unified collection, and reduce material accumulation and residue.

[0044] Below the inner cylinder 13 is the sorting mechanism, which includes a sealing device 4, a rotor device 2, and a drive device 3.

[0045] To improve the problem of large sealing gaps formed by the "h-shaped labyrinth" sealing ring 41 used in Example 1, in this application, the sealing ring 41 is set as a vertical "z" shape, and a combination of hard sealing and air sealing is used to improve the sealing performance of the classifier.

[0046] like Figure 4As shown, the sealing device 4 is located at the top of the rotor device 2. A graphite packing 42 is arranged in the two steel plate grooves on the upper end face of the rotor device 2. The inner wall of the inner cylinder is connected to the "Z"-shaped sealing ring 41, which presses the graphite packing 42 to form a hard seal. The radial distance between the sealing ring 41 and the two sides of the steel plate groove is 6-8 mm. The distance between the lower end of the sealing ring 41 and the upper end of the steel plate groove is 6-8 mm. The distance between the outer ring of the steel plate groove and the inner wall of the inner cylinder 13 is 6-8 mm.

[0047] In addition to the hard seal, several atmospheric access pipes 43 are radially and uniformly welded between the outer wall of the inner cylinder 13 and the inner wall of the outer cylinder 14. The atmospheric access pipes 43 provide positioning support for the inner cylinder 13 and can connect the external atmosphere with the cavity between the bottom of the inner wall of the inner cylinder 13 and the sealing ring 41 to form an air seal.

[0048] like Figure 5 As shown, the rotor device 2 includes a rotor 21, a drive shaft 22, and a tie rod device 23. Several rotor blades 211 are welded to the outside of the rotor 21. The rotor blades 211 have a parallelogram cross-section and a width of 65 mm. Each rotor blade is inclined at 15° in the vertical direction of the high-sealing cyclone dynamic classifier, and the minimum distance between adjacent rotor blades is 35 mm.

[0049] When the classifier is working, the drive shaft 22 is driven to rotate by the motor in the working chamber. The drive shaft 22 can drive the rotor 21 to rotate. At the same time as the rotor 21 rotates, the rotor blades 211 set on it form an airflow. The raw powder that has been ground enters the volute 12 from the feed port 11 along with the airflow.

[0050] When the rotor 21 is running, the linear velocity of the nominal diameter section can reach 25-40 m / s. Due to the high speed of the rotor 21, a strong vortex field is formed between the outer side of the rotor 21 and the inner wall of the volute 12, and the raw powder is separated and classified within this vortex field.

[0051] Combination Figure 6 As shown, the raw powder enters the classifier. After entering through the feed inlet 11, the raw powder moves downwards in a spiral motion with the airflow and then reaches the space between the outer side of the rotor 21 and the inner wall of the volute 12. In the vortex field, the airflow resistance experienced by the fine powder is greater than other forces, so the fine powder enters the central region of the rotor 21 along route A with the airflow. The fine powder that enters the center of the rotor 21 is discharged from the upper outlet of the inner cylinder 13 along with the airflow and is collected as the finished fine powder product.

[0052] exist Figure 6In the vortex field, the coarse powder is subjected to a relatively large centrifugal force and is thrown along route B by the airflow to the inner wall of the lower cone 15. Under the action of gravity, it settles down along the inner wall of the lower cone 15 and finally falls into the lower cone 15 as coarse powder collection.

[0053] In this process, the classification of powder mainly depends on the strength of the vortex field and the size of the airflow in the field. The vortex field is formed by the rotation of the blades 211 on the rotor 21. Therefore, the rotation speed and air volume of the rotor 21 can be adjusted according to the actual sorting requirements. The fineness of the fine powder product obtained by this device can reach 5μm and below, and the quality of the fine powder product can reach 97% and above.

[0054] The above description is only a preferred embodiment of the present invention. It should be noted that, for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A cyclonic multi-stage powder classifying mechanism suitable for ultrafine powders, comprising a housing (1) and a classifying mechanism, characterised in that: The shell (1) comprises an outer cylinder (14) and an inner cylinder (13), the inner cylinder (13) is provided with a sorting mechanism below, the sorting mechanism comprises a rotor device (2), a driving device (3), a sealing device (4); The sealing device (4) comprises a sealing ring (41), a graphite packing (42) and an atmosphere connecting pipe (43), the graphite packing (42) is arranged in a steel plate groove on the top of the rotor device (2), the inner wall of the inner cylinder (13) is connected with the sealing ring (41), and the sealing ring (41) compresses the graphite packing (42); the atmosphere connecting pipe (43) is arranged between the outer wall of the inner cylinder and the inner wall of the outer cylinder.

2. The cyclonic multi-stage powder classifying mechanism suitable for ultrafine powder according to claim 1, wherein: The sealing ring (41) is in the shape of "z".

3. The cyclonic multi-stage powder classifying mechanism suitable for ultrafine powder of claim 1, wherein: The angle between the atmosphere connecting pipe (43) and the horizontal direction is 10°.

4. The cyclonic multi-stage powder classifying mechanism suitable for ultrafine powder of claim 1, wherein: The rotor device (2) is composed of a rotor (21), a transmission shaft (22) and a pull rod device (23); a plurality of rotor blades (211) with the same shape are welded on the outer circle of the rotor (21).

5. The cyclonic multi-stage powder classifying mechanism suitable for ultrafine powder as claimed in claim 4, wherein: The rotor (21) is in the shape of an inverted cone, and the angle between the inclined edge of the rotor (21) and the vertical center line of the high-sealing cyclone cylinder dynamic powder classifier is 8-15°; the height of the rotor (21) is 0.5-0.55 nominal diameter.

6. The cyclonic multi-stage powder classifying mechanism suitable for ultrafine powder according to claim 4, wherein: The vertical cross section of the rotor blade (211) is a parallelogram, the width is 60-70 mm, each rotor blade (211) is inclined by 15-20° in the vertical direction of the high-sealing cyclone cylinder dynamic powder classifier, and the minimum distance between adjacent rotor blades (211) is 35-40 mm.

7. The cyclonic multi-stage powder classifying mechanism suitable for ultrafine powder according to claim 1, wherein: The outer cylinder (14) comprises a feeding port (11), a volute (12) and a lower vertebral body (15).

8. A cyclonic multi-stage powder classifying mechanism suitable for ultra-fine powders as claimed in claim 7, wherein: The diameter of the outer cylinder (14) is twice the diameter of the inner cylinder (13), and the diameter of the inner cylinder (13) is the same as the maximum diameter of the rotor (21).

9. The cyclonic multi-stage powder classifying mechanism suitable for ultrafine powder according to claim 7, wherein: The center point of the volute (12) is offset upward by 150-300 mm in the vertical direction from the center point of the inner cylinder (13).

10. The cyclonic multi-stage powder classifying mechanism suitable for ultrafine powder according to claim 7, wherein: The lower vertebral body (15) is an inclined cone, and the angle between the side surface of the lower vertebral body (15) and the rotation axis is not more than 40°.

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