A multi-stage screening device for modified plastic particles

Abstract

The present invention relates to the technical field of plastic modification, and particularly relates to a multi-stage screening device for modified plastic particles, which includes a box body with a feed inlet at the top. Inside the box body, multiple screening parts are arranged in sequence from top to bottom. The screening part includes an inclined upper sieve plate and a lower sieve plate arranged below the upper sieve plate and slidably connected to the upper sieve plate. A plurality of upper sieve holes are evenly distributed on the upper sieve plate, and a plurality of lower sieve holes are evenly distributed on the lower sieve plate. A plurality of anti-blocking units are correspondingly arranged on the lower sieve plate at positions corresponding to the lower sieve holes. The anti-blocking unit includes a rectangular sunk platform arranged along the length direction of the lower sieve plate, a sliding plate arranged in the rectangular sunk platform, and an impact rod rotatably connected to the lower sieve plate. When the sliding plate slides away from the lower sieve hole, the sliding plate pushes the impact rod to rotate so that the lower end of the impact rod extends into the screening channel. The side wall of the box body is fixedly connected with a cylinder, and the output shaft of the cylinder is arranged along the length direction of the upper sieve plate. This solution can effectively prevent plastic particles from blocking the screening channel and improve the screening rate.

Description

Technical Field

[0001] The present invention relates to the technical field of plastic modification, and particularly relates to a multi-stage screening device for modified plastic particles. Background Art

[0002] Modified plastics refer to plastic products that are processed and modified by methods such as filling, blending, and reinforcing on the basis of general plastics, and have improved performance in aspects such as flame retardancy, strength, impact resistance, and toughness.

[0003] After the modified plastics are metered and mixed, melt-kneaded, extruded, cooled and pelletized, they are then screened to obtain finished products with different particle sizes. The existing screening devices are prone to causing blockage of the sieve holes by plastic particles during screening, reducing the screening rate and screening effect. To solve the above problems, the existing patent CN 109849216 B provides a multi-stage fine screening device for modified plastic particles. This solution sets an adjustment plate that can slide relative to the screening plate in each stage of the screening plate, and sets paired aligned sieve holes in the screening plate and the adjustment plate. During the entire screening process, the screening plate and the adjustment plate generate relative sliding to continuously change the size of the array sieve holes, further achieving the purpose of preventing plastic particles from blocking the sieve holes. The above solution plays a certain role in preventing plastic particles from blocking the sieve holes, but the defect of the above solution is that: since the through-diameter of the sieve holes changes at all times during screening, when the plastic particles roll down along the surface of the sieve plate, only when the plastic particles are just located at the position of the sieve holes and at this time the sieve holes are just at the designed through-diameter, that is, when the sieve holes on the screening plate and the adjustment plate are in the maximum overlapping state, the target plastic particles can pass through the sieve holes and enter the next-stage screening plate to wait for the next-stage screening. This easily causes incomplete screening, fails to achieve the fine screening effect, and affects the screening accuracy; and when there are plastic particles just stuck in the sieve holes when the sieve holes on the screening plate and the adjustment plate are in the maximum overlapping state, at this time the screening plate and the adjustment plate are stuck and cannot slide relative to each other, and thus the anti-blocking effect cannot be achieved. At this time, the cylinder forcibly drives the adjustment plate to slide, so it is easy to cause deformation or even damage to the adjustment plate or the screening plate. Summary of the Invention

[0004] Aiming at the deficiencies of the above-mentioned prior art, the technical problem to be solved by the present invention is: to provide a multi-stage screening device for modified plastic particles to solve the problems that occur in the above-mentioned prior art.

[0005] To solve the above technical problems, a technical solution adopted by the present invention is: to provide a multi-stage screening device for modified plastic particles, including a box body and a plurality of screening parts sequentially arranged from top to bottom in the box body. An inlet is provided at the top of the box body. The screening part includes an inclined upper sieve plate and a lower sieve plate arranged below the upper sieve plate and slidably connected to the upper sieve plate. A plurality of upper sieve holes are evenly distributed on the upper sieve plate. The upper sieve holes of the upper-stage screening part are larger than those of the lower-stage screening part. A plurality of lower sieve holes are evenly distributed on the lower sieve plate corresponding to the upper sieve holes. The upper sieve holes and the lower sieve holes are communicated to form a screening channel for screening plastic particles. A plurality of anti-blocking units are arranged on the lower sieve plate corresponding to the lower sieve holes;

[0006] The anti-blocking unit includes a rectangular sink arranged along the length direction of the lower sieve plate, a sliding plate arranged in the rectangular sink, and an impact rod rotatably connected to the lower sieve plate. The lower sieve hole is located in the rectangular sink. The sliding plate is located on one side of the lower sieve hole. The first end of the sliding plate is close to the lower sieve hole. The sliding plate can slide along the length direction of the lower sieve plate. A spring is arranged in the rectangular sink along the length direction of the lower sieve plate, with one end fixed to the second end of the sliding plate and the other end fixed to the side wall of the rectangular sink. A vertical through groove is arranged on the lower sieve plate along the thickness direction of the lower sieve plate. The impact rod is L-shaped. The upper end of the impact rod passes through the vertical through groove and extends into the rectangular sink to contact the end face of the second end of the sliding plate. The rotation axis of the impact rod is horizontally arranged perpendicular to the length direction of the lower sieve plate. When the sliding plate slides away from the lower sieve hole, the sliding plate pushes the impact rod to rotate so that the lower end of the impact rod extends into the screening channel. A discharge port is arranged on the side wall of the box body to cooperate with the lower end of the upper sieve plate. A cylinder is fixedly connected to the side wall of the box body. The output shaft of the cylinder is arranged along the length direction of the upper sieve plate. The output shaft of the cylinder is fixedly connected to the lower end of the lower sieve plate.

[0007] In the above solution, the control cylinder is used to slide the lower sieve plate so that the lower sieve holes are coaxial with the upper sieve holes. At this time, the screening channel is in the maximum state. When the plastic particles put in from the feed port pass through the upper sieve plate, the plastic particles with a diameter smaller than the screening channel fall onto the next upper sieve plate for further screening, and the plastic particles with a diameter larger than the screening channel are finally collected through the discharge port. When the plastic particles are stuck in the screening channel and the screening rate of the plastic particles is reduced, the control cylinder quickly contracts to slide the lower sieve plate towards the direction close to the cylinder. Under the push of the spring, the sliding plate moves with the lower sieve plate. When the sliding plate is blocked by the plastic particles stuck in the screening channel, the sliding plate is blocked by the plastic particles and cannot move. As the lower sieve plate continues to slide, the sliding plate moves away from the lower sieve holes relative to the lower sieve plate. Since the impact rod moves synchronously with the lower sieve plate, the sliding plate pushes the upper end of the impact rod away from the lower sieve holes, causing the lower end of the impact rod to quickly insert into the screening channel to impact the lower end of the stuck plastic particles and push the plastic particles out of the screening channel, achieving the purpose of preventing the plastic particles from blocking the screening channel. Then, the control cylinder extends to slide the lower sieve plate so that the lower sieve holes are coaxial with the upper sieve holes. Under the elastic force of the spring, the sliding plate returns to its original position, and the impact rod rotates under its own gravity so that the upper end of the impact rod contacts the second end of the sliding plate again.

[0008] Further, a fixed plate is fixedly connected to the bottom of the lower sieve plate, and the impact rod is rotatably connected to the fixed plate by a rotating shaft.

[0009] Further, a chute is provided on the upper surface of the lower sieve plate along the length direction of the lower sieve plate and penetrates through the lower sieve plate. The upper sieve plate is located in the chute and is slidably connected to the lower sieve plate.

[0010] Further, the upper sieve plates of each screening section are arranged in parallel, and a guide plate is provided above each screening section to guide the plastic particles to the higher end of the upper sieve plate of the screening section.

[0011] Further, a first cavity is provided in the guide plate, and a number of first air holes communicating the first cavity with the space above the guide plate are evenly distributed on the upper surface of the guide plate. The first cavity is communicated with a blower provided on the box body through an air pipe.

[0012] Further, the diameter of the lower sieve holes is larger than the diameter of the upper sieve holes.

[0013] Further, an exhaust hole is provided at the top of the box body.

[0014] Compared with the prior art, the present invention has at least the following beneficial effects:

[0015] 1. Under normal screening conditions, the upper sieve holes and the lower sieve holes in the present invention do not move relative to each other all the time, so that the size of the screening channel composed of the upper sieve holes and the lower sieve holes remains unchanged. As a result, the probability that plastic particles with a diameter smaller than the diameter of the screening channel fall into the next-level screening unit through the screening channel is higher, avoiding the phenomenon that plastic particles with a diameter smaller than the maximum diameter of the screening channel finally flow into the discharge port of the current-level screening unit due to the continuous change of the diameter of the screening channel. Therefore, the screening of the present invention is faster and more accurate.

[0016] 2. When plastic particles are blocked in a certain screening channel, when the operating cylinder drives the lower sieve plate to slide, the impact rod can eject the plastic particles blocked in the screening channel from the screening channel, preventing the plastic particles from continuously blocking the screening channel.

[0017] 3. A deflector is provided to guide the plastic particles to the higher end of the corresponding upper sieve plate, preventing the phenomenon that plastic particles are directly discharged from the discharge port without being screened. The structure of the deflector makes the wind generated by the fan spray upward from the upper surface of the deflector, which can further dry the plastic particles and disperse the plastic particles on the deflector. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings described herein are used to provide a further understanding of the present application, and constitute a part of the present application. The schematic embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation to the present application. In the drawings:

[0019] Figure 1 is a schematic diagram of the overall structure of the present invention.

[0020] Figure 2 is Figure 1 an enlarged view of part A in

[0021] Figure 3 is a schematic diagram of the cooperation between the upper sieve plate and the lower sieve plate in the top view direction.

[0022] Figure 4 is Figure 3 an enlarged view of part B in

[0023] Figure 5 is a schematic diagram of the cooperation between the upper sieve plate and the lower sieve plate in the left view direction.

[0024] Figure 6 is a schematic diagram when plastic particles are stuck in the screening channel.

[0025] Figure 7 is a schematic diagram of the impact rod rotating to impact plastic particles when the lower sieve plate slides.

[0026] Figure 8 is a schematic diagram of the moment when plastic particles are ejected from the screening channel by the impact rod.

[0027] Figure 9 Schematic diagram of the cooperation between the impact rod and the lower sieve plate in the left view direction.

[0028] Figure 10 Schematic diagram of the deflector structure.

[0029] The meanings of the reference numerals in the drawings are as follows:

[0030] Box body 10, feed inlet 101, discharge outlet 102, exhaust hole 103, upper sieve plate 20, upper sieve hole 201, lower sieve plate 21, lower sieve hole 211, rectangular sunk platform 212, vertical through groove 213, sliding groove 214, sliding plate 23, impact rod 24, fixing plate 241, rotating shaft 242, spring 25, deflector 26, first cavity 261, first air hole 262, air pipe 27, air cylinder 28, fan 30, plastic particles 40. Specific embodiments

[0031] To make the objectives, technical solutions, and advantages of the present application clearer, the technical solutions of the present application will be clearly and completely described below in conjunction with specific embodiments of the present application and the corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of the present application.

[0032] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which this invention belongs. The terms used in the specification of this invention herein are only for the purpose of describing specific embodiments, and are not intended to limit the invention.

[0033] A modified plastic particle multi-stage screening device in this embodiment, as Figure 1 shown, includes a box body 10 and a plurality of sieve parts sequentially arranged from top to bottom inside the box body 10. In this embodiment, a total of 3 sieve parts are arranged from top to bottom. In other feasible embodiments, the number of sieve parts can be reasonably determined according to actual needs, which will not be elaborated one by one. The top of the box body 10 is provided with a feed inlet 101 and an exhaust hole 103. Combining Figure 3 , Figure 5 shown, the sieve part includes an inclined upper sieve plate 20 and a lower sieve plate 21 arranged below the upper sieve plate 20. As Figure 1 shown, the upper sieve plates 20 of each sieve part are parallelly arranged, and a deflector 26 is arranged above each sieve part to direct the plastic particles to the higher end of the upper sieve plate 20 of the sieve part. As Figure 10As shown, a first cavity 261 is provided inside the flow guide plate 26. A plurality of first air holes 262 that communicate the first cavity 261 with the space above the flow guide plate 26 are evenly distributed on the upper surface of the flow guide plate 26. The first cavity 261 is communicated with a blower 30 provided on the outer wall of the box body 10 through an air pipe 27.

[0034] As Figure 5 shown, a sliding groove 214 is provided on the upper surface of the lower sieve plate 21 along the length direction of the lower sieve plate 21 and penetrates through the lower sieve plate 21. The upper sieve plate 20 is located in the sliding groove 214 and is slidably connected to the lower sieve plate 21. The sliding groove 214 is a T-shaped groove, and the upper sieve plate 20 is integrally a T-shaped plate that cooperates with the sliding groove 214, so that the upper sieve plate 20 can only slide along the length direction of the lower sieve plate 21.

[0035] Refer to as Figure 3 、 Figure 6 shown, a plurality of upper sieve holes 201 are evenly distributed on the upper sieve plate 20. The upper sieve holes 201 of the upper-stage sieve distribution are larger than those of the lower-stage sieve distribution. A plurality of lower sieve holes 211 corresponding to the upper sieve holes 201 are evenly distributed on the lower sieve plate 21. The diameter of the lower sieve holes 211 is larger than that of the upper sieve holes 201. The upper sieve holes 201 and the lower sieve holes 211 are communicated to form a screening channel for screening plastic particles 40. A plurality of anti-blocking units are provided on the lower sieve plate 21 corresponding to the lower sieve holes 211.

[0036] Refer to Figures 1-6 , the anti-blocking unit includes a rectangular sunk platform 212 arranged along the length direction of the lower sieve plate 21, a sliding plate 23 arranged in the rectangular sunk platform 212, and an impact rod 24 rotatably connected to the lower sieve plate 21. The lower sieve hole 211 is located in the rectangular sunk platform 212. The sliding plate 23 is located on one side of the lower sieve hole 211. The first end of the sliding plate 23 is close to the lower sieve hole 211. The first end of the sliding plate 23 is in a semi-circular arc shape that cooperates with the upper sieve hole 201. The sliding plate 23 can only slide along the length direction of the lower sieve plate 21. A spring 25 is arranged in the rectangular sunk platform 212 along the length direction of the lower sieve plate 21. One end of the spring 25 is fixedly connected to the second end of the sliding plate 23, and the other end of the spring 25 is fixedly connected to the side wall of the rectangular sunk platform 212. A vertical through groove 213 is arranged on the lower sieve plate 21 along the thickness direction of the lower sieve plate 21. The impact rod 24 is integrally in an L shape. The upper end of the impact rod 24 passes through the vertical through groove 213 and extends into the rectangular sunk platform 212 and contacts the end surface of the second end of the sliding plate 23. The rotation axis 242 line of the impact rod 24 is horizontally arranged perpendicular to the length direction of the lower sieve plate 21. As Figure 9As shown, the specific way that the impact rod 24 is rotatably connected to the lower sieve plate 21 is as follows: a fixing plate 241 is fixedly connected to the bottom of the lower sieve plate 21. There are two fixing plates 241, and the two fixing plates 241 are respectively located on both sides of the vertical through groove 213 and are arranged parallel to the vertical through groove 213. The upper end of the fixing plate 241 is fixedly connected to the lower sieve plate 21. A rotating shaft 242 is rotatably arranged on the fixing plate 241, and the impact rod 24 is rotatably connected to the fixing plate 241 through the rotating shaft 242. When the sliding plate 23 slides away from the lower sieve hole 211, the sliding plate 23 pushes the impact rod 24 to rotate around the rotating shaft 242 so that the lower end of the impact rod 24 extends into the screening channel. A discharge port 102 is provided on the side wall of the box body 10 and is matched with the lower end of the upper sieve plate 20.

[0037] As Figure 2 shown, a cylinder 28 is fixedly connected to the inner side wall of the box body 10. The output shaft of the cylinder 28 is arranged along the length direction of the upper sieve plate 20, and the output shaft of the cylinder 28 is fixedly connected to the lower end of the lower sieve plate 21. The cylinder 28 is externally connected to a gas source and a solenoid valve that can control the action of the cylinder 28.

[0038] The working principle of this solution is as follows:

[0039] Control the cylinder 28 to make the lower sieve plate 21 slide so that the lower sieve hole 211 is coaxial with the upper sieve hole 201. At this time, the screening channel formed by the upper sieve hole 201 and the lower sieve hole 211 is in the maximum state. Operate the fan 30 to make the air flow spray out from the first air holes 262 on the surface of each guide plate 26. Put the plastic particles 40 into the box body 10 from the feed port 101. The uppermost guide plate 26 guides the plastic particles 40 to the surface of the uppermost upper sieve plate 20. The plastic particles 40 are dispersed by the air flow when flowing through the surface of the uppermost guide plate 26. Then when the plastic particles 40 pass through the upper sieve plate 20, the plastic particles 40 with a diameter smaller than the screening channel fall onto the next upper sieve plate 20 for further screening, and the plastic particles 40 with a diameter larger than the screening channel are finally collected via the discharge port. Refer to Figures 6-8, when the plastic particles 40 get stuck in the screening channel and the screening rate of the plastic particles 40 decreases, the control cylinder 28 contracts rapidly to make the lower sieve plate 21 slide towards the direction close to the cylinder 28. Under the push of the spring 25, the sliding plate 23 moves with the lower sieve plate 21. When the sliding plate 23 is blocked by the plastic particles 40 stuck in the screening channel, the sliding plate 23 is blocked by the plastic particles 40 and cannot move. As the lower sieve plate 21 continues to slide, the sliding plate 23 moves away from the lower sieve holes 211 relative to the lower sieve plate 21. Since the impact rod 24 moves synchronously with the lower sieve plate 21, the sliding plate 23 pushes the upper end of the impact rod 24 away from the lower sieve holes 211, so that the lower end of the impact rod 24 quickly inserts into the screening channel to impact the lower end of the stuck plastic particles 40 and push the plastic particles 40 out of the screening channel, achieving the purpose of preventing the plastic particles 40 from blocking the screening channel. Then, control the cylinder 28 to extend to make the lower sieve plate 21 slide so that the lower sieve holes 211 are coaxial with the upper sieve holes 201. Under the elastic force of the spring 25, the sliding plate 23 returns to its original position. The impact rod 24 rotates under its own gravity so that the upper end of the impact rod 24 contacts the second end of the sliding plate 23 again. For the convenience of automatic control, an external controller can also be used. The controller controls the cylinder 28 to make the cylinder shaft perform one or several telescopic actions at regular intervals, so as to automatically push the stuck plastic particles 40 out of the screening channel.

[0040] The above are only embodiments of the present invention. Common knowledge such as specific structures and characteristics known in the solution is not described in detail here. It should be noted that for those skilled in the art, without departing from the structure of the present invention, several deformations and improvements can also be made, which should also be regarded as the protection scope of the present invention, and these will not affect the implementation effect of the present invention and the practicability of the patent. The protection scope required by this application should be based on the content of its claims, and the specific implementation manners described in the specification can be used to explain the content of the claims.

Claims

1. A multi-stage screening device for modified plastic particles, comprising a box body, and a feed inlet is provided at the top of the box body. It is characterized in that: A plurality of screening parts are sequentially arranged in the box body from top to bottom. The screening part includes an inclined upper sieve plate and a lower sieve plate arranged below the upper sieve plate and slidably connected to the upper sieve plate; A plurality of upper sieve holes are evenly distributed on the upper sieve plate. The upper sieve holes of the upper-stage screening part are larger than those of the lower-stage screening part. A plurality of lower sieve holes are evenly distributed on the lower sieve plate corresponding to the upper sieve holes. The upper sieve holes and the lower sieve holes are communicated to form a screening channel for screening plastic particles. A plurality of anti-blocking units are arranged on the lower sieve plate corresponding to the lower sieve holes; The anti-blocking unit includes a rectangular sink arranged along the length direction of the lower sieve plate, a sliding plate arranged in the rectangular sink, and an impact rod rotatably connected to the lower sieve plate. The lower sieve hole is located in the rectangular sink. The sliding plate is located on one side of the lower sieve hole. The first end of the sliding plate is close to the lower sieve hole. The sliding plate can slide along the length direction of the lower sieve plate. A spring is arranged in the rectangular sink along the length direction of the lower sieve plate, with one end fixedly connected to the second end of the sliding plate and the other end fixedly connected to the side wall of the rectangular sink. A vertical through groove is arranged on the lower sieve plate along the thickness direction of the lower sieve plate. The impact rod is L-shaped. The upper end of the impact rod passes through the vertical through groove and extends into the rectangular sink and contacts the end face of the second end of the sliding plate. The rotation axis of the impact rod is horizontally arranged perpendicular to the length direction of the lower sieve plate. When the sliding plate slides away from the lower sieve hole, the sliding plate pushes the impact rod to rotate so that the lower end of the impact rod extends into the screening channel. A discharge port is arranged on the side wall of the box body to cooperate with the lower end of the upper sieve plate. A cylinder is fixedly connected to the side wall of the box body. The output shaft of the cylinder is arranged along the length direction of the upper sieve plate. The output shaft of the cylinder is fixedly connected to the lower end of the lower sieve plate.

2. The multi-stage screening device for modified plastic particles according to claim 1, characterized in that: A fixing plate is fixedly connected to the bottom of the lower sieve plate. The impact rod is rotatably connected to the fixing plate through a rotating shaft.

3. The multi-stage screening device for modified plastic particles according to claim 2, wherein: A chute is arranged on the upper surface of the lower sieve plate along the length direction of the lower sieve plate and penetrates through the lower sieve plate. The upper sieve plate is located in the chute and is slidably connected to the lower sieve plate.

4. A multi-stage screening device for modified plastic particles according to claim 3, characterized in that: The upper sieve plates of each screening part are arranged in parallel. A guide plate is arranged above each screening part to guide the plastic particles to the higher end of the upper sieve plate of the screening part.

5. The multi-stage screening device for modified plastic particles according to claim 4, characterized in that: A first cavity is arranged in the guide plate. A plurality of first air holes communicating the first cavity with the space above the guide plate are evenly distributed on the upper surface of the guide plate. The first cavity is communicated with a blower arranged on the box body through an air pipe.

6. The multi-stage screening device for modified plastic particles according to claim 5, wherein: The diameter of the lower sieve hole is larger than that of the upper sieve hole.

7. A multi-stage screening device for modified plastic particles according to claim 6, characterized in that: An exhaust hole is arranged at the top of the box body.

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