CN217528175U - Pore diameter gradual change screening machine for polycrystalline silicon - Google Patents

Abstract

The utility model discloses a pore diameter gradual change screening machine for polycrystalline silicon, which relates to the technical field of polycrystalline silicon production and comprises a machine body, a bracket, a power mechanism, a transmission mechanism and a plurality of grading screening mechanisms; the power mechanism is in transmission connection with the transmission mechanism, and the transmission mechanism is in transmission connection with the plurality of grading mechanisms respectively and drives the grading mechanisms to sieve materials in a vibrating manner; a plurality of grades of screening mechanisms are in proper order from last to arranging down, the screening mechanism top of head end is provided with the pan feeding mouth, terminal screening mechanism bottom is provided with the powder export, each grade of screening mechanism all includes the screening cavity, sieve and screening exit channel, the sieve is located the screening cavity bottom of this grade of screening mechanism, and be located the screening cavity top of next grade of screening mechanism, in sending into next grade of screening mechanism with the material that the external diameter is less than this grade of sieve mesh, the end-to-end connection screening exit channel of sieve, send into the material that the external diameter is greater than this grade of sieve mesh and sieve exit channel, the sieve of a plurality of grades of screening mechanisms has included the sieve of sieve mesh aperture gradual change.

Description

Pore diameter gradual change screening machine for polycrystalline silicon

Technical Field

The utility model relates to a polycrystalline silicon production technical field, more specifically say and relate to a hole diameter gradual change screening machine for polycrystalline silicon.

Background

Polycrystalline silicon is a form of elemental silicon. When the molten elemental silicon is solidified under the undercooling condition, silicon atoms are arranged in the form of diamond crystal lattices to form a plurality of crystal nuclei, and if the crystal nuclei grow into crystal grains with different crystal plane orientations, the crystal grains are combined to be crystallized into polycrystalline silicon.

During the mechanical crushing process of polycrystalline silicon production, silicon materials with different specifications and sizes need to be screened and classified by using a screening machine, the current sieve plates in the market are all uniform in aperture, the aperture is uniform and has limitation, only the size of the aperture can be screened, and the screening loss and the powder control are small; in addition, the polycrystalline silicon blocks and granules are irregular in shape, and the sieve plate is easy to block in the sieving process.

In the prior art, a patent with publication number CN205833641U discloses a polycrystalline silicon lump material sorting device, which comprises a power supply system, a large-particle-size lump material sieve plate with sieve pores, a medium-particle-size lump material sieve plate and a small-particle-size lump material sieve plate, wherein the large-particle-size lump material sieve plate is arranged on an upper layer in an inclined state, a silicon material storage pool is arranged above the large-particle-size lump material sieve plate, and the large-particle-size lump material sieve plate is connected with a large-particle-size lump material collecting box; the medium-particle-size lump material sieve plate is obliquely arranged below the large-particle-size lump material sieve plate and is connected with a medium-particle-size lump material collecting box; the small-particle-size lump material sieve plate is arranged below the medium-particle-size lump material sieve plate in an inclined state and is connected with a small-particle-size lump material collecting box, and a pull-type silicon crushed material and micro silicon powder collecting box is arranged below the small-particle-size lump material sieve plate. The utility model arranges the large, medium and small grain diameter lump material sieve plates obliquely according to an angle of 30 degrees, automatically sorts the lump materials according to different sizes and enters a corresponding silicon material collecting box; the problems of high labor cost, low production efficiency and unsatisfactory effect of manual separation are solved; and the structure is simple and the price is low.

However, the polysilicon lump material sorting device provided by the above patent still has consistent screen holes of each screen plate, and still has the problems of uncontrollable powder rate control and loss and easy occurrence of blockage phenomenon.

SUMMERY OF THE UTILITY MODEL

In order to overcome the defects in the prior art, the utility model aims to provide a pore diameter gradual change screening machine for polycrystalline silicon to solve the problem that the screening loss and the powder control are small and the blocking phenomenon easily occurs in the prior art.

In order to realize the above purpose, the utility model discloses a technical scheme:

a pore diameter gradual change screening machine for polycrystalline silicon comprises a machine body, a bracket, a power mechanism, a transmission mechanism and a plurality of grades of screening mechanisms;

the machine body is arranged on the support, the plurality of grading mechanisms are all positioned in the machine body, the power mechanism is in transmission connection with the transmission mechanism, and the transmission mechanism is in transmission connection with the plurality of grading mechanisms respectively and drives the grading mechanisms to sieve materials in a vibrating manner;

the screening mechanism comprises a plurality of stages of screening mechanisms, wherein the screening mechanisms are sequentially arranged from top to bottom, a feeding port is formed in the top end of the screening mechanism at the head end, a powder outlet is formed in the bottom end of the screening mechanism at the tail end, each stage of screening mechanism comprises a screening cavity, a screening plate and a screening outlet channel, the screening plate is positioned at the bottom end of the screening cavity of the screening mechanism at the stage and is positioned at the top end of the screening cavity of the screening mechanism at the next stage, materials with the outer diameters smaller than the screen holes of the screening plate at the stage are fed into the screening mechanism at the next stage, and the tail end of the screening plate is connected with the screening outlet channel and feeds the materials with the outer diameters larger than the screen holes of the screening plate at the stage into the screening outlet channel to be discharged; the sieve plates of the screening mechanisms in the multiple stages comprise at least one sieve plate with gradually changed sieve pore diameters, and the sieve plates with gradually changed sieve pore diameters gradually reduce the pore diameters of the sieve pores in the material transmission direction.

Further, the screening machine includes tertiary screening mechanism, and the sieve mesh of first order screening mechanism is the unanimous circular in aperture, and the sieve mesh of second level screening mechanism is the circular of aperture gradual change, and the sieve mesh of third level screening mechanism is the square of size gradual change.

Further, the diameter of the circular sieve holes of the first-stage screening mechanism is 35-40mm, the diameter of the gradually-changed circular sieve holes of the second-stage screening mechanism is 4-6mm, and the size of the gradually-changed square sieve holes of the third-stage screening mechanism is 1.2 x 1.2-1.5 x 1.5mm.

Furthermore, the diameter of the circular sieve holes of the sieve plate of the second-stage screening mechanism is gradually reduced and the number of the circular sieve holes is gradually increased in the material transmission direction; the sieve plate of the third-stage screening mechanism is characterized in that the size of a square sieve hole of the third-stage screening mechanism is gradually reduced and the quantity of the square sieve holes is gradually increased in the material transmission direction.

Further, the sieve plate and the sieving outlet channel are arranged to incline from the material inlet end to the material outlet end.

Further, the screening cavity of each grade of screening mechanism all is connected with the dust removal mouth.

Further, a spring is mounted on the bracket.

The utility model has the advantages that:

the utility model provides an aperture gradual change screening machine, the sieve of a plurality of grades of screening mechanisms have included the sieve of sieve mesh aperture gradual change, under the prerequisite of guaranteeing the product powder rate, reduce loss and product powder rate, increase the proportion of occupying of high value product, reduce simultaneously and appear sieve blocking phenomenon.

Drawings

Fig. 1 is a front view of the present invention;

FIG. 2 is a top view of the present invention;

fig. 3 is a side view of the present invention;

fig. 4 is a schematic view of the three-stage screening mechanism of the present invention;

fig. 5 is a schematic view of the gradient sieve plate of the present invention;

fig. 6 is a partial schematic view of the gradually-varied circular sieve plate of the present invention;

fig. 7 is a partial schematic view of the gradually-changed square sieve plate of the present invention;

reference numerals:

1. a body; 2. a support; 3. a power mechanism; 4. a screening mechanism; 41. a screening chamber; 42. a sieve plate; 43. a screening outlet channel; 44. a dust removal port; 5. a feeding port; 6. a powder outlet; 7. a spring.

Detailed Description

The conception, specific structure, and technical effects of the present invention will be clearly understood and fully described below with reference to the accompanying drawings and embodiments, so as to fully understand the objects, features, and effects of the present invention.

Example 1

A sieving machine with gradually changed aperture for polysilicon is shown in figures 1-7 and comprises a machine body 1, a bracket 2, a power mechanism 3, a transmission mechanism and a plurality of grading sieving mechanisms 4.

The machine body 1 is arranged on the support 2, the plurality of stages of screening mechanisms are all positioned in the machine body 1, the power mechanism 3 is in transmission connection with the transmission mechanism, and the transmission mechanism is in transmission connection with the plurality of stages of screening mechanisms respectively and drives the screening mechanisms to vibrate to screen materials.

The screening mechanisms 4 of a plurality of stages are sequentially arranged from top to bottom, the top end of the screening mechanism 4 at the head end is provided with a material inlet 5, the bottom end of the screening mechanism 4 at the tail end is provided with a powder outlet 6, each stage of screening mechanism 4 comprises a screening cavity 41, a screening plate 42 and a screening outlet channel 43, the screening plate 42 is positioned at the bottom end of the screening cavity 41 of the stage of screening mechanism 4 and positioned at the top end of the screening cavity 41 of the next stage of screening mechanism 4, materials with the outer diameter smaller than the screening holes of the stage of screening plate 42 are sent into the next stage of screening mechanism 4, the tail end of the screening plate 42 is connected with the screening outlet channel 43, and materials with the outer diameter larger than the screening holes of the stage of screening plate 42 are sent into the screening outlet channel 43 to be discharged; the sieve plates 42 of the multi-stage screening mechanism 4 comprise at least one sieve plate 42 with gradually changed pore diameters, and the pore diameters of the sieve pores of the sieve plate 42 with gradually changed pore diameters are gradually reduced in the material transmission direction.

In this embodiment, the power mechanism 3 is a conventional motor, and the transmission mechanism is a conventional transmission mechanism, and transmits the rotation of the motor to the sieving mechanism 4 after conversion, so as to drive the sieving mechanism 4 to vibrate for material sieving. In this embodiment, specifically, the weight (unbalanced weight) installed up and down on the motor shaft is used to convert the rotation motion of the motor into horizontal, vertical and inclined three-dimensional motion, and then the motion is transmitted to the screen surface of the screen plate 42, so that the material is screened in the outward-expanding involute motion on the screen surface.

The multi-stage screening mechanism 4 is used for screening materials in a grading manner, the feeding port 5 is used for adding the materials, and the powder outlet 6 is used for discharging the screened powder. The material moves in the screening cavity 41, and the power mechanism 3 drives the screen plate 42 of each grade to screen the material in a vibrating manner.

Example 2

In this embodiment, a further improvement is made on the basis of embodiment 1, as shown in fig. 4-7, the screening machine includes three-stage screening mechanisms 4, the sieve plate 42 of the first-stage screening mechanism 4 is circular with uniform aperture, the sieve plate 42 of the second-stage screening mechanism 4 is circular with gradually-changed aperture, and the sieve plate 42 of the third-stage screening mechanism 4 is square with gradually-changed size.

The diameter of the circular sieve hole of the first-stage screening mechanism 4 is 35-40mm, and the diameter is 35mm in the embodiment; the diameter of the gradually-changed circular sieve hole of the second-stage screening mechanism 4 is 4-6mm, and a plurality of sieve holes of 6mm, 5mm and 4mm are sequentially arranged along the transmission direction in the embodiment; the size of the gradually-changed square sieve pore of the third-stage screening mechanism 4 is 1.2 × 1.2-1.5 × 1.5mm, and a plurality of sieve pores of 1.5mm, 1.4mm, 1.3 mm and 1.2mm are sequentially arranged in the transmission direction in the embodiment.

In the embodiment, the first-stage screening mechanism 4 of the sieve plate with the consistent mesh aperture is used for screening silicon materials with the diameter of more than 35-40mm as block material products; a second-stage screening mechanism 4 of a circular sieve pore sieve plate with gradually changed pore diameters, which is used for screening 6-35mm silicon materials as a re-feeding product; and a third-stage screening mechanism 4 of the sieve plate with the square sieve pores with gradually changed apertures is used for screening 1.2-6mm silicon materials as crushed material products, and meanwhile, the square sieve pores are not easy to block materials relative to the circular sieve pores.

The screen plate 42 and the screening outlet channel 43 are both arranged to be inclined from the material inlet end to the material outlet end, so that at a certain angle of inclination the material automatically moves in the conveying direction under the influence of the vibrations.

The diameter of the circular sieve holes of the sieve plates 42 of the second-stage screening mechanism 4 is gradually reduced and the number of the sieve plates is gradually increased in the material transmission direction; the sieve plate 42 of the third-stage screening mechanism 4 has the square sieve holes with gradually reduced sizes and gradually increased quantities in the material transmission direction.

In the prior art, the sieve plate 42 of the second-stage screening mechanism 4 has a round sieve pore size of 6mm, and the sieve plate 42 of the third-stage screening mechanism 4 has a square sieve pore size of 1.5mm × 1.5mm. The re-feeding products screened by the second-stage screening mechanism 4 and the crushed material products screened by the third-stage screening mechanism 4 are main products screened by the screening machine and are used for subsequent production. However, the existing sieve plate has a uniform mesh size, which results in a high amount of pulverized material to be finally discharged from the powder outlet 6, and thus in a high loss of the pulverized material. And simultaneously, the sieve pores are easy to be blocked.

In this embodiment, the sieve plate 42 of the second-stage screening mechanism 4 is taken as an example for explanation, and a plurality of sieve holes of 6mm, 5mm and 4mm are sequentially arranged along the conveying direction, and are sieve with gradually changed aperture.

The sieve plate 42 sieve mesh of the second-stage screening mechanism 4 gradually changes from 6mm during feeding to 4mm,6mm region of the discharge, can screen a part of silicon material below 6mm, can keep a part of silicon material above 5mm in the screening part during the 5mm region, can keep the last small part of silicon material above 4mm during the 4mm region, and the fine powder below 4mm is simultaneously screened completely, and the product of the second-stage screening mechanism 4 is finally discharged from the screening outlet channel 43 (the product of the second-stage screening mechanism 4 is corresponding to the sieve plate with the same aperture of 6mm, and the discharge amount is increased). Therefore, compared with the 6mm uniform sieve mesh in the prior art, the crushed material discharged from the powder outlet 6 is relatively low, the powder does not exceed the standard and meets the standard, and the normal output ratio is improved (the sieve plate with the 6mm uniform pore diameter is filled, the powder rate is higher, the quality is excessive, the product output ratio is low, and the income is low).

The problem of clogging is that: the sieve plate 42 of the second-stage screening mechanism 4 has sieve holes which are relatively dense in a small hole area of 4mm compared with a large area of 6mm, and due to the fact that the screening frequency is unchanged, silicon materials are bounced up when being clamped on the sieve plates, the blocking phenomenon can be reduced, but the blocking phenomenon is not represented. Meanwhile, the sieve holes are relatively more, and compared with 6mm macropores with fewer sieve holes, the sieve does not influence the sieving of materials even if a few sieve holes are blocked.

The screening cavity 41 of each grade of screening mechanism 4 is connected with a dust removal port 44, the dust removal port is connected with a dust suction device, fine dust generated in the screening process is sucked by air suction, and pollution of powder and silicon materials is reduced.

The support 2 is provided with a spring 7 which is connected with the support through the spring to lead the vibration part to vibrate in a complex spiral shape.

Taking a certain screening machine of a certain company as an example, in the prior art, the sieve plate of the second-stage screening mechanism is in a circular shape with consistent aperture, 6mm, and the proportion of the re-thrown product is 68.32%; the screening machine is a 6mm round hole screen plate, and is replaced by a 4+5+6mm screen plate, on the premise of ensuring that the powder rate meets the standard (0.07% before the powder rate is improved, 0.14% after the powder rate is improved, and the standard is less than or equal to 0.15%), the proportion of the re-thrown product is 69.14%, and is increased by 0.82% relative to the prior art.

In the prior art, the sieve plate of the third-stage screening mechanism has uniform square sieve pores which are 1.5mm multiplied by 1.5mm, and the proportion of crushed material products is 4.72 percent; the sieve plate of the sieving machine is a sieve plate with square holes of 1.5 multiplied by 1.5mm, and is replaced by a gradual change sieve plate of 1.2 multiplied by 1.2-1.5 multiplied by 1.5mm, on the premise of ensuring that the powder rate meets the standard (0.15 percent before the powder rate is improved, 0.25 percent after the powder rate is improved, and the standard is less than or equal to 0.3 percent), the proportion of crushed aggregates is 4.89 percent, and is improved by 0.17 percent compared with the prior art.

For better understanding, the utility model discloses, following is to the theory of operation of the utility model make a complete description:

when screening the material, the power mechanism 3 rotates and transmits the rotation to the transmission mechanism, and the transmission mechanism drives the sieve plate 42 in each stage of the three-stage screening mechanism 4 to vibrate.

As shown in fig. 4, polysilicon material to be screened is fed into the screening chamber 41 of the first screening mechanism 4 from the feeding port 5, under the vibration action of the first-stage screen plate 42 at the bottom end thereof, the material with the outer diameter smaller than the screen hole of the first-stage screen plate 42 falls into the screening chamber 41 of the second screening mechanism 4 through the screen hole of the first-stage screen plate 42, and lump material product larger than the screen hole of the first-stage screen plate 42 moves to the end of the first-stage screen plate 42 and is discharged through the screening outlet channel 43 of the first-stage screening mechanism 4.

The material falling into the screening chamber 41 of the second screening mechanism 4 moves in the screening chamber 41 of the second screening mechanism 4, and under the vibration action of the second screening plate 42 of the second screening mechanism 4, the material with the outer diameter smaller than the screening hole of the second screening plate 42 falls into the screening chamber 41 of the third screening mechanism 4 through the screening hole of the second screening plate 42, and the material larger than the second screening plate 42 is re-thrown into the product, moves to the tail end of the second screening plate 42 and is discharged through the screening outlet channel 43 of the second screening mechanism 4.

The material falling into the screening cavity 41 of the third screening mechanism 4 moves in the screening cavity 41 of the third screening mechanism 4, and under the vibration action of the third screening plate 42 of the third screening mechanism 4, the material with the outer diameter smaller than the screening hole of the third screening plate 42 falls into the bottom end of the machine body through the screening hole of the third screening plate 42 and is discharged through the powder outlet 6, and the crushed material product larger than the screening hole of the third screening plate 42 moves to the tail end of the third screening plate 42 and is discharged through the screening outlet channel 43 of the third screening mechanism 4.

The embodiments of the present invention have been described in detail, but the present invention is not limited to the embodiments, and those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention, and the equivalents or substitutions are included in the scope of the present invention defined by the claims.

Claims (7)

1. The utility model provides a pore diameter gradual change screening machine for polycrystalline silicon which characterized in that: comprises a machine body (1), a bracket (2), a power mechanism (3), a transmission mechanism and a plurality of grading mechanisms (4);

the machine body (1) is mounted on the support (2), the plurality of grading mechanisms (4) are located in the machine body (1), the power mechanism (3) is in transmission connection with the transmission mechanism, and the transmission mechanism is in transmission connection with the plurality of grading mechanisms (4) respectively and drives the grading mechanisms to sieve materials in a vibrating manner;

the screening mechanisms (4) in the multiple stages are sequentially arranged from top to bottom, a feeding opening (5) is formed in the top end of the screening mechanism (4) at the head end, and a powder outlet (6) is formed in the bottom end of the screening mechanism (4) at the tail end; each grade of screening mechanism (4) comprises a screening cavity (41), a screening plate (42) and a screening outlet channel (43), wherein the screening plate (42) is positioned at the bottom end of the screening cavity (41) of the grade of screening mechanism (4) and at the top end of the screening cavity (41) of the next grade of screening mechanism (4), materials with the outer diameter smaller than the screening holes of the screening plate (42) are sent into the next grade of screening mechanism (4) for continuous screening, the tail end of the screening plate (42) is connected with the screening outlet channel (43), and materials with the outer diameter larger than the screening holes of the screening plate (42) are sent into the screening outlet channel (43) to be discharged; the sieve plates (42) of the screening mechanisms (4) comprise at least one sieve plate (42) with gradually changed sieve pore diameters, and the sieve plates (42) with gradually changed sieve pore diameters gradually reduce the pore diameters of the sieve pores in the material transmission direction.

2. The polysilicon pore size gradually-changing screening machine according to claim 1, wherein: the screening machine includes tertiary screening mechanism (4), and sieve (42) sieve mesh of first order screening mechanism (4) is the unanimous circular in aperture, and sieve (42) sieve mesh of second order screening mechanism (4) is the circular of aperture gradual change, and sieve (42) sieve mesh of third level screening mechanism (4) is the square of size gradual change.

3. The polysilicon pore size gradually-changing screening machine according to claim 2, wherein: the diameter of the circular sieve holes of the first-stage screening mechanism (4) is 35-40mm, the diameter of the gradually-changed circular sieve holes of the second-stage screening mechanism (4) is 4-6mm, and the size of the gradually-changed square sieve holes of the third-stage screening mechanism (4) is 1.2 multiplied by 1.2-1.5 multiplied by 1.5mm.

4. The screen grader for polysilicon with gradually changed aperture according to claim 2 or 3, wherein: the diameter of the circular sieve holes of the sieve plate (42) of the second-stage screening mechanism (4) is gradually reduced and the number of the circular sieve holes is gradually increased in the material transmission direction; and the sieve plate (42) of the third-stage screening mechanism (4) is characterized in that the size of a square sieve hole is gradually reduced and the quantity of the square sieve holes is gradually increased in the material transmission direction.

5. The graded-aperture screening machine for polycrystalline silicon according to claim 1, characterized in that: the sieve plate (42) and the sieve outlet channel (43) are arranged to incline from the material inlet end to the material outlet end.

6. The polysilicon pore size gradually-changing screening machine according to claim 1, wherein: the screening cavity (41) of each stage of screening mechanism (4) is connected with a dust removal port (44).

7. The polysilicon pore size gradually-changing screening machine according to claim 1, wherein: and a spring (7) is arranged on the bracket (2).

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