Screening device for plastic particles

Abstract

The utility model relates to the technical field of material screening, in particular to a screening device for plastic particles. The screening device for the plastic particles comprises a support, a screening assembly and a driving assembly, the screening assembly comprises a first screen and a second screen which are both cylindrical and obliquely arranged, and the second screen is located in the first screen; the axis of the first screen is parallel to the axis of the second screen, and the axis of the first screen is located above the axis of the second screen. The two ends of the first screen are connected with connecting rods in sliding connection with the support correspondingly, the second screen is rotationally connected with the support, and the driving assembly can drive the second screen to rotate around the axis of the second screen. The maximum distance between the inner wall of the first screen and the outer wall of the second screen is larger than the length of target particles and smaller than two times of the length of the target particles. The mesh size of the second screen is larger than that of the first screen. The long strips can be completely screened out, and particles blocked in meshes of the screen can be easily removed.

Description

Technical Field

[0001] The utility model relates to the technical field of material screening, in particular to a screening device for plastic particles. Background Art

[0002] In the production process of plastic particles, the plastic raw materials are extruded through an extruder and then cooled to form filament-shaped plastics. These filament-shaped plastics can be further processed into plastic particles by cutting. However, in the above production process, it is inevitable to produce some fine-particle powders and large-sized pellets. Among them, fine-particle powders are usually debris generated during the cutting process; large-sized pellets usually include long strips (referring to pellets with a length greater than 2 times that of normal particles, usually caused by abnormal traction speed of filament-shaped plastics), connected pellets (referring to pellets formed by two or more particles sticking together side by side, usually caused by failure to separate in time after extrusion), centipede strips (referring to particles that are cut but not completely cut between multiple plastic particles), etc.

[0003] Existing devices for screening plastic particles usually use multi-stage screening, using screens with different apertures in each screening stage to screen out fine-sized powder and large-sized particles in the plastic particles. However, relying solely on the aperture of the screen, it is impossible to completely distinguish between long strips and normal particles (because the diameters of long strips and normal particles are similar); and the screen mesh of conventional screening devices is easily blocked by long strips and centipede strips, and it is difficult to clear the blockage.

[0004] In order to improve the screening effect of plastic particles, it is urgently necessary to propose a new screening device for plastic particles, which can ensure that the long strips are completely screened out and easily remove the particles blocked in the mesh of the screen. Utility Model Content

[0005] The utility model aims to provide a screening device for plastic particles, which can at least partially overcome the above technical problems, ensure that long strips are completely screened out, and easily remove particles blocked in the mesh of the screen.

[0006] The utility model provides a screening device for plastic particles, comprising a bracket, a screening component and a driving component, the screening component comprising a first screen and a second screen, both of which are cylindrical and inclined, the second screen being located inside the first screen; the axis of the first screen is parallel to the axis of the second screen, and the axis of the first screen is located above the axis of the second screen; both ends of the first screen are respectively connected with connecting rods slidably connected to the bracket, the second screen is rotatably connected to the bracket, and the driving component can drive the second screen to rotate around its own axis; the maximum distance between the inner wall of the first screen and the outer wall of the second screen is greater than the length of the target particle and less than twice the length of the target particle; the mesh size of the second screen is greater than the mesh size of the first screen.

[0007] Furthermore, the driving assembly includes a motor, and a first gear is arranged on the output shaft of the motor; and a second gear meshing with the first gear is arranged on the outer peripheral surface of the second screen.

[0008] Furthermore, a limiting boss is provided on the connecting rod, and a spring is sleeved on the outer circumferential surface of the connecting rod, one end of the spring abuts against the limiting boss, and the other end abuts against the bracket; the motor can drive the connecting rod to slide on the bracket.

[0009] Furthermore, a push portion is provided on the connecting rod, and a cam is provided on the output shaft, and a peripheral surface of the cam abuts against the push portion.

[0010] Furthermore, the screening assembly also includes a third screen, which is located inside the second screen, and the outer diameter of the third screen is equal to the inner diameter of the second screen; the mesh size of the third screen is equal to the mesh size of the second screen, and the third screen is slidably connected to the second screen; the screening device also includes an adjustment component, which can adjust the third screen to move along the axis of the second screen.

[0011] Furthermore, the adjustment component includes a telescopic mechanism, the free end of which is connected to the third screen; through the telescopic action of the telescopic mechanism, the third screen can be driven to move along the axis of the second screen, so that the mesh holes of the third screen and the mesh holes of the second screen overlap or stagger.

[0012] Furthermore, an annular limiting groove is provided on the end surface of the third screen, and the free end is connected to a connector adapted to be connected to the annular limiting groove.

[0013] Furthermore, the free end is connected to the connecting head via an elastic body.

[0014] Furthermore, the screening assembly also includes a first outlet groove, which is located inside the second screen and fixedly connected to the bracket.

[0015] Furthermore, the screening assembly also includes a second outlet slot, which is located below the first screen and fixedly connected to the bracket.

[0016] Compared with the prior art, the utility model has the following advantages and beneficial effects:

[0017] 1. A screening device for plastic particles provided by an embodiment of the present disclosure realizes multi-stage screening of plastic particles to be screened by setting a first screen and a second screen, and can effectively screen plastic particles into large-size particles, target particles and fine-size powder. By setting the maximum distance between the inner wall of the first screen and the outer wall of the second screen to be greater than the length of the target particles and less than twice the length of the target particles, it can ensure that long strips are completely screened out;

[0018] 2. A screening device for plastic particles provided by an embodiment of the present disclosure can improve the screening effect of the first screen by arranging a boss, a push portion and a spring on the connecting rod, and driving a cam driven by a motor to drive the connecting rod and the bracket to slide relative to each other, thereby driving the first screen to shake, thereby ensuring that fine-particle powder is completely screened out, and ensuring the quality of the target particles finally obtained;

[0019] 3. A screening device for plastic particles provided by an embodiment of the present disclosure can make the mesh holes of the third screen overlap or stagger with the mesh holes of the second screen by adjusting the position of the third screen, so that the combined screen composed of the third screen and the second screen has a combined mesh hole with an adjustable size range, which can adapt to the screening work of target particles of different sizes under different batches of production, and when it is used to screen target particles of different sizes in different production batches, there is no need to dismantle and replace the screen, and the mesh hole size of the combined screen composed of the second screen and the third screen can be adjusted by simply adjusting the action of the telescopic mechanism; in addition, when the combined mesh hole is blocked, the particles blocked in the combined mesh hole can be removed by driving the third screen to reciprocate in the axial direction;

[0020] 4. A screening device for plastic particles provided by an embodiment of the present disclosure has a process in which a cam pushes the connecting rod and the bracket to produce relative sliding, thereby causing the first screen to vibrate, and a slight vibration will also occur on the bracket accordingly, and then this slight vibration is transmitted to the telescopic mechanism and acts on the third screen; the free end and the connecting head are connected by an elastic body, so that this slight vibration can act evenly on the third screen, causing the third screen to correspondingly perform slight reciprocating motion along the axial direction, thereby causing a slight change in the combined mesh size of the combined screen composed of the second screen and the third screen, thereby preventing particles from getting stuck in the combined mesh and causing blockage. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The drawings described herein are used to provide a further understanding of the embodiments of the present utility model, constitute a part of this application, and do not constitute a limitation of the embodiments of the present utility model. In the drawings:

[0022] Figure 1 It is a schematic diagram of the three-dimensional structure of a screening device for plastic particles according to an embodiment of the utility model;

[0023] Figure 2 It is a front view of a screening device for plastic particles according to an embodiment of the utility model;

[0024] Figure 3 A longitudinal sectional view of a screening device for plastic particles according to an embodiment of the utility model, wherein the meshes of the third screen and the meshes of the second screen are in an overlapping state;

[0025] Figure 4 Another longitudinal sectional view of a screening device for plastic particles according to an embodiment of the utility model, wherein the meshes of the third screen and the meshes of the second screen are in a staggered state;

[0026] Figure 5 Based on Figure 3 A partial enlarged view of area A is shown;

[0027] Figure 6 Based on Figure 4 A partial enlarged view of region B is shown;

[0028] Figure 7 Based on Figure 5 A partial enlarged view of region C is shown;

[0029] Figure 8 Based on Figure 6 A partial enlarged view of area D is shown.

[0030] Marks and corresponding parts names in the attached drawings:

[0031] 1- bracket; 21- first screen; 22- second screen; 221- second gear; 23- third screen; 31- motor; 311- output shaft; 312- first gear; 313- cam; 4- connecting rod; 41- limiting boss; 42- push part; 5- spring; 61- free end; 62- fixed end; 71- connector; 72- elastic body; 81- first size; 82- second guide groove; 83- third guide groove; 84- fourth guide groove. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below in combination with the embodiments and drawings. The schematic implementation mode and description of the utility model are only used to explain the utility model and are not intended to limit the utility model. It should be noted that the utility model is already in the actual development and use stage.

[0033] Existing screening devices for screening plastic particles usually adopt multi-stage screening, using screens with different apertures in each screening stage, so as to screen out fine-sized powder and large-sized particles in the plastic particles. However, it is impossible to completely distinguish long strips from normal particles by relying solely on the aperture of the screen (because the diameters of long strips and normal particles are comparable, and long strips can also pass through the mesh of the screen longitudinally); and the mesh of the conventional screening device is easily blocked by long strips and centipede strips, and it is difficult to remove the blockage. The utility model proposes a screening device for plastic particles, which ensures that long strips are completely screened out and particles blocked in the mesh of the screen are easily removed.

[0034] Embodiment 1:

[0035] like Figures 1 to 4 As shown, the present embodiment provides a screening device for plastic particles, comprising a bracket 1, a screening component and a driving component.

[0036] The screening assembly comprises a first screen 21 and a second screen 22, both of which are cylindrical and inclined, wherein the second screen 22 is located inside the first screen 21; the axis of the first screen 21 is parallel to the axis of the second screen 22, and the axis of the first screen 21 is located above the axis of the second screen 22;

[0037] Both ends of the first screen 21 are respectively connected with connecting rods 4 which are slidably connected to the bracket 1, the second screen 22 is rotatably connected to the bracket 1, and the driving assembly can drive the second screen 22 to rotate around its own axis;

[0038] The maximum distance between the inner wall of the first sieve 21 and the outer wall of the second sieve 22 is greater than the length of the target pellet and less than twice the length of the target pellet; the mesh size of the second sieve 22 is greater than the mesh size of the first sieve 21.

[0039] It should be understood that the screening device for plastic particles provided in the embodiment of the utility model is also a multi-stage screening device, and its feeding side is the inside of the second screen 22; therefore, in order to achieve the screening effect, the mesh size of the second screen 22 needs to be slightly larger than the size of the target particles, thereby allowing the target particles and fine-particle powder to pass through and preventing the passage of connected particles and centipede strips; the mesh size of the first screen 21 is smaller than the size of the target particles, thereby allowing the passage of fine-particle powder and preventing the passage of target particles.

[0040] Based on this, when using the above-mentioned screening device for plastic particles to screen plastic particles, the plastic particles are added from the inside of the high side of the second screen 22; while the particles move obliquely downward inside the second screen 22, the second screen 22 also rotates, and the inclined mesh surface and the self-rotation action allow the target particles and fine-particle powder to quickly pass through the second screen 22 and enter the channel between the second screen 22 and the first screen 21, and then the fine-particle powder falls downward through the first screen 21, and the target particles remain inside the first screen 21 and flow out from the low side of the first screen 21. Among them, since the maximum distance between the inner wall of the first screen 21 and the outer wall of the second screen 22 is greater than the length of the target pellet and less than twice the length of the target pellet, it is obvious that the maximum distance appears between the inner peripheral surface below the first screen 21 and the outer peripheral surface below the second screen 22. After the strips in the plastic particles to be screened are longitudinally inserted into the mesh of the second screen 22, due to the distance limit between the first screen 21 and the second screen 22, the strips cannot enter the channel between the second screen 22 and the first screen 21. During the rotation of the second screen 22, the strips inserted into the mesh of the second screen 22 are gradually pushed back into the second screen 22 (in the process of rotating from the bottom of the second screen 22 to the top, the distance between the first screen 21 and the second screen 22 is gradually reduced, so the strips are pushed back, and when rotating to the top, gravity also causes the strips to fall back into the second screen 22). Therefore, the screening effect of the strips is ensured, and the situation in which the mesh of the second screen 22 is blocked by the strips is avoided. In addition, both ends of the first screen 21 are respectively connected with connecting rods 4 slidably connected to the bracket 1 , which can facilitate the installation of the first screen 21 and adjust the distance between the first screen 21 and the second screen 22 .

[0041] It should be understood that, in the above-mentioned screening process, it is obvious that after the strips fall back into the second screen 22, they may be inserted into the mesh of the second screen 22 again. In the case of a large number of strips, more meshes are occupied, which seriously affects the screening efficiency. Based on this, the screening assembly also includes a first guide slot, which is located inside the second screen 22 and fixedly connected to the bracket 1. Thus, after the strips inserted into the mesh of the second screen 22 are gradually pushed back into the second screen 22, they fall into the first guide slot and are discharged to the outside of the screen through the first guide slot. In the above-mentioned screening process, large-sized particles are isolated inside the second screen 22, the target particles are in the channel between the second screen 22 and the first screen 21, and the fine-sized powder falls downward through the mesh of the first screen 21. In order to facilitate the classification of the screened plastic particles, preferably, the screening component also includes a second guide slot 82, which is located below the first screen 21 and is fixedly connected to the bracket 1; the screening component also includes a third guide slot 83, which is connected to the lower side of the second screen 22; the screening component also includes a fourth guide slot 84, which is connected to the lower side of the first screen 21. As a result, the fine-sized powder falling downward through the mesh of the first screen 21 is collected and guided out by the second guide slot 82, the large-sized particles inside the second screen 22 are guided out through the third guide slot 83, and the target particles in the channel between the second screen 22 and the first screen 21 are guided out through the fourth guide slot 84.

[0042] Preferably, in the above-mentioned screening device for plastic particles, the driving assembly includes a motor 31, and a first gear 312 is arranged on the output shaft 311 of the motor 31; a second gear 221 meshing with the first gear 312 is arranged on the outer peripheral surface of the second screen 22. Thus, the motor 31 provides power and the gears drive the second screen 22 to rotate. It is possible to provide continuous and smooth rotation input, so that the screening device for plastic particles can perform continuous screening work.

[0043] Embodiment 2:

[0044] like Figures 1 to 4 As shown, this embodiment is based on embodiment 1, and the difference is that:

[0045] The present embodiment provides a screening device for plastic particles, wherein a limiting boss 41 is provided on the connecting rod 4, and a spring 5 is sleeved on the outer peripheral surface of the connecting rod 4, one end of the spring 5 abuts against the limiting boss 41, and the other end abuts against the bracket 1;

[0046] The motor 31 can drive the connecting rod 4 to slide on the bracket 1 .

[0047] Specifically, a push portion 42 is further provided on the connecting rod 4 , and a cam 313 is provided on the output shaft 311 . The circumferential surface of the cam 313 abuts against the push portion 42 .

[0048] Based on this, the motor 31 drives the cam 313 abutting against the push portion 42 to rotate while driving the second screen 22 to rotate, which can cause relative sliding between the connecting rod 4 and the bracket 1 assembly, thereby causing the first screen 21 to vibrate. This shaking action acts on the plastic particles inside the first screen 21, which can improve the screening effect of the first screen 21, ensure that fine-particle powder is completely screened out, and ensure the quality of the target particles finally obtained. It should be understood that in order to achieve shaking, the connecting rods 4 connected to both ends of the first screen 21 should be parallel to each other.

[0049] Embodiment 3:

[0050] like Figures 1 to 8 As shown, this embodiment is based on embodiment 1, and the difference is that:

[0051] In a screening device for plastic particles provided in this embodiment, the screening assembly further includes a third screen 23, the third screen 23 is located inside the second screen 22, and the outer diameter of the third screen 23 is equal to the inner diameter of the second screen 22;

[0052] The mesh size of the third screen 23 is equal to the mesh size of the second screen 22, and the third screen 23 is slidably connected to the second screen 22;

[0053] The screening device further comprises an adjusting component, which is capable of adjusting the third screen 23 to move along the axis of the second screen 22 .

[0054] More specifically, the adjustment assembly includes a telescopic mechanism, and the free end 61 of the telescopic mechanism is connected to the third screen 23;

[0055] Through the telescopic action of the telescopic mechanism, the third screen 23 can be driven to move along the axis of the second screen 22, so that the meshes of the third screen 23 and the meshes of the second screen 22 are overlapped or staggered.

[0056] Based on this, by adjusting the position of the third screen 23 (driving the third screen 23 to move along the axis of the second screen 22), the mesh of the third screen 23 can be made to coincide with the mesh of the second screen 22 (such as Figure 3 , Figure 5 as shown) or staggered (as shown Figure 4 , Figure 6As shown), the combined screen composed of the third screen 23 and the second screen 22 has a combined mesh with an adjustable size range, which can adapt to the screening of target particles of different sizes under different batches of production, and when it is used to screen target particles of different sizes in different production batches, there is no need to replace the screens. The mesh size of the combined screen composed of the second screen 22 and the third screen 23 can be adjusted by simply adjusting the action of the telescopic mechanism; in addition, when the combined mesh is blocked, the particles blocked in the combined mesh can be removed by driving the third screen 23 to reciprocate axially.

[0057] Preferably, if Figure 7 , Figure 8 As shown, an annular limiting groove is provided on the end surface of the third screen 23, and a connector 71 adapted to be connected to the annular limiting groove is connected to the free end 61. Based on this, the cooperation between the limiting groove and the connector 71 can enable the telescopic mechanism to reliably limit the axial position of the third screen 23, so as to facilitate driving the third screen 23 to extend or retract in the axial direction.

[0058] Preferably, the free end 61 is connected to the connector 71 via an elastic body 72. Based on this, when the cam 313 pushes the connecting rod 4 and the bracket 1 to produce relative sliding, thereby causing the first screen 21 to shake, there will also be a slight shake on the bracket 1, and then this slight shake is transmitted to the telescopic mechanism and acts on the third screen 23. By connecting the free end 61 and the connector 71 via the elastic body 72, this slight shake can be evenly applied to the third screen 23, so that the third screen 23 correspondingly performs a slight reciprocating motion along the axial direction, thereby causing a slight change in the size of the combined mesh of the combined screen composed of the second screen 22 and the third screen 23, thereby preventing the particles from getting stuck in the combined mesh and causing blockage.

[0059] The specific implementation methods described above further illustrate the purpose, technical solutions and beneficial effects of the utility model in detail. It should be understood that the above description is only the specific implementation method of the utility model and is not used to limit the protection scope of the utility model. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the utility model should be included in the protection scope of the utility model.

Claims

1. A screening device for plastic particles, comprising a support (1), a screening component and a driving component, characterized in that: The screening assembly comprises a first screen (21) and a second screen (22) both of which are cylindrical and inclined, the second screen (22) being located inside the first screen (21); the axis of the first screen (21) is parallel to the axis of the second screen (22), and the axis of the first screen (21) is located above the axis of the second screen (22); Both ends of the first screen (21) are respectively connected to connecting rods (4) which are slidably connected to the bracket (1); the second screen (22) is rotatably connected to the bracket (1); and the driving assembly is capable of driving the second screen (22) to rotate around its own axis; The maximum distance between the inner wall of the first screen (21) and the outer wall of the second screen (22) is greater than the length of the target pellet and less than twice the length of the target pellet; the mesh size of the second screen (22) is greater than the mesh size of the first screen (21).

2. A screening device for plastic particles according to claim 1, characterized in that: The driving assembly comprises a motor (31), and a first gear (312) is arranged on an output shaft (311) of the motor (31); A second gear (221) meshing with the first gear (312) is provided on the outer peripheral surface of the second screen (22).

3. A screening device for plastic particles according to claim 2, characterized in that: A limiting boss (41) is provided on the connecting rod (4), and a spring (5) is sleeved on the outer peripheral surface of the connecting rod (4), one end of the spring (5) abuts against the limiting boss (41), and the other end abuts against the bracket (1); The motor (31) is capable of driving the connecting rod (4) to slide on the bracket (1).

4. A screening device for plastic particles according to claim 3, characterized in that: A push portion (42) is also provided on the connecting rod (4), and a cam (313) is provided on the output shaft (311), wherein the peripheral surface of the cam (313) abuts against the push portion (42).

5. A screening device for plastic particles according to any one of claims 1 to 4, characterized in that: The screening assembly further comprises a third screen (23), the third screen (23) being located inside the second screen (22), and the outer diameter of the third screen (23) being equal to the inner diameter of the second screen (22); The mesh size of the third screen (23) is equal to the mesh size of the second screen (22), and the third screen (23) is slidably connected to the second screen (22); The screening device further comprises an adjusting component, wherein the adjusting component is capable of adjusting the third screen (23) to move along the axis of the second screen (22).

6. A screening device for plastic particles according to claim 5, characterized in that: The adjustment assembly comprises a telescopic mechanism, wherein a free end (61) of the telescopic mechanism is connected to the third screen (23); Through the telescopic action of the telescopic mechanism, the third screen (23) can be driven to move along the axis of the second screen (22), so that the mesh holes of the third screen (23) and the mesh holes of the second screen (22) are overlapped or staggered.

7. A screening device for plastic particles according to claim 6, characterized in that: An annular limiting groove is provided on the end surface of the third screen (23), and the free end (61) is connected to a connector (71) adapted to be connected to the annular limiting groove.

8. A screening device for plastic particles according to claim 7, characterized in that: The free end (61) is connected to the connecting head (71) via an elastic body (72).

9. A screening device for plastic particles according to claim 1, characterized in that: The screening assembly further comprises a first outlet groove, the first outlet groove being located inside the second screen (22) and fixedly connected to the bracket (1).

10. A screening device for plastic particles according to claim 1, characterized in that: The screening assembly further comprises a second outlet groove (82), wherein the second outlet groove (82) is located below the first screen (21) and is fixedly connected to the bracket (1).

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