Multi-stage concrete gravel screening device

Abstract

The multi-stage concrete gravel screening device comprises a machine shell and further comprises a screening drum, driving assemblies are arranged on the peripheries of the outer walls of the front end and the rear end of the screening drum, and the screening drum is rotationally arranged in a cavity of the machine shell through the driving assemblies; the gear bins are correspondingly arranged on the left side and the right side of the front end opening and the rear end opening of the machine shell respectively, the gear bins are connected with a cavity of the machine shell in a communicating mode, and transmission gears in transmission connection with the driving assembly are arranged in the gear bins. The cleaning bins are communicated and arranged on the two sides of the machine shell in an equal-length mode, cleaning mechanisms are arranged in the cleaning bins and comprise a plurality of sector plates which take the transmission shaft as the center and are arranged on the outer side of the transmission shaft in a circumferential mode, brush heads are arranged at the outer side ends of the sector plates, and the brush head ends are close to the screening drum in an attached mode; an opening is formed in the upper end of the feeding bin, one side of a bin body of the feeding bin is connected with one end of the machine shell in a communicating mode, a discharging opening is formed in the other end of the machine shell, and a conveying auger transversely arranged at the central axis in the screening drum is erected from one end of the outer side of the feeding bin to one end of the discharging opening.

Description

Technical Field

[0001] The invention relates to the technical field of screening equipment, in particular to a multi-stage concrete sand and gravel screening device. Background Art

[0002] In the process of using concrete, concrete sand and gravel of different sizes need to be used in different construction fields. For example, coarse sand is often used in the pouring construction of large buildings. Larger sand and gravel sizes can fill and pour quickly and strengthen the structural hardness of large buildings. Medium sand is often used in the field of road construction. It can avoid the unevenness caused by coarse sand paving and the defects of long road construction period and unstable structure caused by excessive dilution of fine sand. Fine sand is usually used as concrete coating on the outer surface of the wall of domestic buildings. Therefore, concrete sand and gravel of different sizes need to be clearly distinguished when used and applied to different construction fields.

[0003] When screening concrete sand and gravel, a screening device is needed to distinguish the messy concrete sand and gravel by size. However, since concrete sand and gravel usually have an irregular structure, they are very easy to be blocked in the mesh of the screening device during the screening process, thereby reducing the efficiency of the screening device. Workers are required to clean them on time to ensure the smooth screening function.

[0004] The Chinese patent application number "202420027478.2" discloses a vibrating screening device for stone materials used in mines, including a machine body and a screening mechanism. The screening mechanism is arranged inside the machine body, and the screening mechanism includes a shaft body, a roller, a main screen drum, a motor and a gear. The shaft body is obliquely installed at the four corners of the machine body, and rollers are installed at both ends of the shaft body. The motor drives the shaft body and the roller to rotate through the gear, and then drives the main screen drum to rotate through the roller, so that the main screen drum keeps rotating during the screening process of the stone passing through the main screen drum, and the stone stuck in the screen hole will move to the inside of the machine body. However, in reality, in the sand and gravel screening process, since the stones stuck in the sieve holes are usually some stones pressed at the bottom by the piles of stones to be screened, when they are tightly stuck in the mesh holes due to the pressure caused by the piles of stones, it is not the case that the above-mentioned patents only rotate the main screen drum to rotate to the upper end of the mesh holes where the stones are stuck, and the stones can be naturally thrown off without receiving external pressure. Therefore, the technical means proposed in the above-mentioned patents cannot completely solve the cleaning work of stones with different degrees of sticking, and there are still large technical defects and room for improvement. Summary of the invention

[0005] In view of the above problems, the present invention proposes a concrete sand and gravel multi-stage screening device to solve the technical problem of sand and gravel being stuck in the sieve holes and difficult to clean mentioned in the background technology.

[0006] In order to achieve the above object, the present invention is implemented by adopting the following technical solutions:

[0007] A multi-stage concrete sand and gravel screening device comprises a casing and a sub-screening cylinder, wherein a driving assembly is arranged circumferentially on the outer walls of the front and rear ends of the sub-screening cylinder, and the sub-screening cylinder is rotatably arranged in the casing cavity by the driving assembly;

[0008] Gear bins, where multiple gear bins are respectively arranged on the left and right sides of the front and rear ports of the casing, the gear bins are conductively connected to the casing cavity, and the gear bins are equipped with transmission gears that are transmission-connected to the drive assembly;

[0009] A cleaning chamber, which is connected and arranged at both sides of the casing in equal length, and has a cleaning mechanism inside the cleaning chamber, which includes a plurality of fan plates centered on the transmission shaft and circumferentially arranged outside the transmission shaft, and a brush head is arranged at the outer end of the fan plate, and the brush head end of the fan plate is close to the sub-screen cylinder;

[0010] A feed bin, the upper end of which is open, one side of the feed bin body is conductively connected to one end of the casing, and the other end of the casing is provided with a discharge port, a feed auger is set up from one end of the outer side of the feed bin to one end of the discharge port and is horizontally placed at the central axis of the sub-screening cylinder, and one end of the feed auger is coaxially connected to a first motor;

[0011] A plurality of discharge bins are evenly distributed at the lower end of the casing.

[0012] Furthermore, a first concave slide groove is circumferentially opened on the inner walls of the front and rear ports of the casing, and the driving components at the front and rear ends of the sub-screen drum are respectively embedded in the first slide groove. The bottom plates of the cleaning bins on both sides of the casing are arranged to be tilted downward, and an opening is arranged on the side of one end of the cleaning bin tilted downward.

[0013] Furthermore, the driving assembly includes a second slide groove opened on the outer walls of the front and rear openings of the sub-screen cylinder, the second slide groove is arranged corresponding to the first slide groove, a plurality of rollers are evenly distributed around the second slide groove, and a limit retainer is arranged between the plurality of rollers.

[0014] Furthermore, the limit retainer is an annular structure with a plurality of limit holes evenly distributed on the outer surface, the roller is limit-embedded in the limit holes, and the limit retainer and the roller are arranged between the first slide groove and the second slide groove.

[0015] Furthermore, the driving assembly also includes a gear track circumferentially arranged on the outer walls of the two ends of the sub-screen cylinder, and the gear track is meshed and connected with the transmission gear in the gear bin.

[0016] Furthermore, the outer side of the transmission shaft has a plurality of shaft seats protruding around the circumference and continuously arranged along the length of the transmission shaft. The shaft seat is hollow inside and open at the upper end. A positioning shaft is arranged inside the shaft seat and is mounted between the left and right ends of the shaft seat. The fan plate is installed through the positioning shaft. One end of the transmission shaft is coaxially connected to the second motor.

[0017] Furthermore, a positioning hole is opened at the bottom of the fan plate, and the fan plate is swingably set on the positioning shaft through the bottom positioning hole. A mounting groove is opened on the outer side of the fan plate, and multiple pin holes are horizontally arranged on the two plate surfaces before and after the mounting groove, and the brush head is embedded in the mounting groove.

[0018] Furthermore, the brush head is as long as the fan plate, and a clamping piece as long as the mounting groove is provided on one side of the brush head. The brush head is embedded in the mounting groove through the clamping piece, and the clamping piece and the mounting groove are fixedly connected by a pin provided in the pin hole.

[0019] Furthermore, the sub-screen drum is a multi-section screen drum structure, and the multi-section screen drum is a multi-section structure with mesh size increasing from small to large from one end close to the feed bin to the end of the discharge port, and each section of the sub-screen drum is arranged in a discharge bin placed at the lower end of the casing.

[0020] Furthermore, a third motor is coaxially connected to one side of one of the transmission gears, and a transmission belt is sleeved between the transmission gear on the same side as the transmission gear connected to the third motor.

[0021] The beneficial effects of the present invention are as follows: the present invention arranges a rotatable sub-screening drum inside the casing, and the sub-screening drum is connected to the driving components at its front and rear ends through the transmission gears arranged in the gear bins on both sides of the casing to drive it to rotate, and at the same time, the feeding auger extending from the feed bin to the other end of the casing rotates in the relative direction with it. After the sand and gravel enter the sub-screening drum, the self-rotating screen drum and the rotating feeding auger can not only ensure the gradual pushing of the sand and gravel from inlet to outlet to prevent the sand and gravel from accumulating in the sub-screening drum, but also the relative rotation of the sub-screening drum and the feeding auger can keep the sand and gravel in a scattered state at all times, thereby reducing the The probability of pressing the lower sand and gravel into the sieve holes due to the large amount of sand and gravel accumulation is reduced. During the rotation of the sub-screening drum, cleaning components with brush heads on the outside are also provided in the cleaning bins on both sides of the casing. The cleaning components rotate to make the brush heads and the sub-screening drum close to each other, and the two rotate relatively. The brush heads exert pressure on the surface of the passing sub-screening drum to further knock down the sand and gravel stuck in the sieve holes to avoid clogging of the mesh holes. Finally, the fan plate arranged on the outside of the transmission shaft can fan the dust caused by the sand and gravel screened in the sub-screening drum into the cleaning bin during the rotation process to avoid the impact on the service life caused by the accumulation of dust in the bin body of the casing. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0023] Figure 2 It is a schematic diagram of the overall structure of the present invention from another angle;

[0024] Figure 3 A top view of the present invention;

[0025] Figure 4 It is a schematic diagram of the internal structure of the casing of the present invention;

[0026] Figure 5 It is a schematic diagram of the structure of one end of the casing of the present invention;

[0027] Figure 6 It is a structural schematic diagram of one end of the screening cylinder of the present invention;

[0028] Figure 7 It is a schematic diagram of the structure of the driving assembly of the present invention;

[0029] Figure 8 It is a schematic diagram of the structure of the cleaning component of the present invention;

[0030] Fig. 9 for Figure 8 Schematic diagram of the local structure of A.

[0031] Explanations in the figure: 1. Casing; 101. Discharge port; 102. Discharge bin; 103. Cleaning bin; 104. Gear bin; 105. First chute; 2. Feed bin; 3. Screening cylinder; 301. Second chute; 302. Limit retainer; 303. Roller; 304. Gear rail; 4. Feeding auger; 401. First motor; 5. Transmission shaft; 501. Shaft seat; 502. Positioning shaft; 503. Second motor; 6. Fan plate; 601. Mounting slot; 602. Pin hole; 603. Positioning hole; 7. Brush head; 701. Clamp; 8. Transmission gear; 801. Third motor; 802. Transmission belt. DETAILED DESCRIPTION

[0032] The technical solutions in the embodiments of the present invention will be described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0033] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited by the specific implementation disclosed below.

[0034] In the description of the present invention, it is necessary to understand that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0035] Embodiment 1:

[0036] like Figures 1 to 4 A multi-stage concrete sand and gravel screening device shown in the figure includes a casing 1, which will serve as a supporting structure for the entire device and is used to accommodate other components. It also includes a sub-screening cylinder 3, and a driving component is circumferentially arranged on the outer walls of the front and rear ends of the sub-screening cylinder 3. The sub-screening cylinder 3 is arranged in the cavity of the casing 1 through the driving component. By arranging the driving component at the front and rear ends of the sub-screening cylinder 3, the sub-screening cylinder 3 can be more stably and rotatably installed inside the cavity of the casing 1. A gear bin 104 is also arranged. There are at least four gear bins 104, and the four gear bins 104 are respectively arranged on the left and right sides of the front and rear ports of the casing 1, and at least one gear bin 104 is arranged on each side of the front and rear ends. The gear bin 104 is conductively connected to the cavity of the casing 1, and a transmission gear 8 is arranged in each gear bin 104, and the transmission gear 8 is rotatably arranged in the gear bin 104, as shown in FIG. Figure 4As shown, the transmission gear 8 is meshed and connected with the driving assembly, and the four transmission gears 8 respectively support the four bottom corners on the left and right sides of the lower end of the sub-screen drum 3, so that it can be more stably transmitted and maintain the stability of operation. Furthermore, a cleaning bin 103 is also provided, and the cleaning bins 103 are respectively connected and arranged at equal lengths on both sides of the casing 1. The bottom plates of the cleaning bins 103 on both sides of the casing 1 are arranged to be tilted downward, and an opening is arranged on the side of one end of the cleaning bin 103 tilted downward. The cleaning bin 103 has a built-in cleaning mechanism, which includes a plurality of fan plates 6 centered on the transmission shaft 5 and circumferentially arranged on the outside of the transmission shaft 5. The fan plates A brush head 7 is provided at the outer end of 6, and the brush head 7 end of the fan plate 6 is close to the sub-screening cylinder 3. During the operation of the sub-screening cylinder 3, the brush head 7 is in contact with the sub-screening cylinder 3 and contacts the outer surface of the sub-screening cylinder 3, thereby applying pressure to the surface of the sub-screening cylinder 3, so that the brush head 7 can brush off the stones stuck in the sieve holes and re-enter the sub-screening cylinder 3 for sieving, thereby solving the problem of sieve hole blockage; further, a feed bin 2 is provided, the upper end of which is open and serves as a feed port in the stone screening process, and the stones to be screened enter the feed bin 2 from this port, one side of the feed bin 2 is conductively connected to one end of the casing 1, and the other end of the casing 1 is provided with a discharge port 101 A feeding auger 4 is set up from one end of the outer side of the feed bin 2 to one end of the discharge port 101 and is horizontally placed at the central axis of the sub-screen cylinder 3. One end of the feeding auger 4 is coaxially connected to a first motor 401. The feeding auger 4 is driven by the first motor 401, so that the sand and gravel entering the feed bin 2 from the feed port at the upper end of the feed bin 2 is driven by the feeding auger 4 and moves gradually from the feed port to the discharge port 101. In the process of movement, the sand and gravel are turned over by the feeding auger 4, so that the sand and gravel are loosened to prevent them from piling up in one place. At the same time, the movement of the sand and gravel promoted by the feeding auger 4 can promote the movement of the sand and gravel in a manner that the relative vibration structure can In order to further reduce the degree of wear of the equipment and the noise generated during the transportation of sand and gravel, in the process of pushing the material by the feeding auger 4, the material passing through the sub-screen drum 3 is screened step by step according to the different sizes, and a plurality of discharge bins 102 are evenly distributed at the lower end of the casing 1. The sub-screen drum 3 is a multi-section screen drum structure, and the multi-section screen drums are multi-section structures with mesh sizes increasing step by step from one end close to the feed bin 2 to the end of the discharge port 101. Each section of the sub-screen drum 3 is arranged in a discharge bin 102 located at the lower end of the casing 1. The lower end of the discharge bin 102 is open to discharge sand and gravel with different particle sizes for differentiated stacking.

[0037] As a technical solution of this embodiment, further, Figure 5 As shown, the inner walls of the front and rear ports of the casing 1 are circumferentially provided with a first concave chute 105, and the drive components at the front and rear ends of the sub-screen drum 3 are respectively embedded in the first chute 105. The first chute 105 is used to mount the protruding parts of the drive components arranged at the front and rear ends of the sub-screen drum 3, as shown in FIG. Figure 6 and Figure 7 As shown, the driving assembly includes a second slide groove 301 provided on the outer walls of the front and rear openings of the sub-screen drum 3, the second slide groove 301 is provided corresponding to the first slide groove 105, and a plurality of rollers 303 are evenly arranged around the second slide groove 301, the rollers 303 can reduce the friction between the sub-screen drum 3 and the casing 1, and can ensure the smooth rotation of the sub-screen drum 3 inside the casing, reduce the wear between the casing 1 and the sub-screen drum 3, and increase the service life, and a limit retainer 302 is provided between the plurality of rollers 303, and the limit retainer 302 is an annular structure with a plurality of limit holes evenly arranged on the outer surface, and the rollers 30 3 is embedded in the limiting hole, and the limiting retainer 302 and the roller 303 are arranged between the first slide groove 105 and the second slide groove 301. The limiting retainer 302 prevents the roller 303 from changing its position during the operation of the sub-screen drum 3, and always maintains the position of the roller 303, thereby ensuring the uniform force during the rotation of the sub-screen drum 3 and the limiting protection of the sub-screen drum 3. At the same time, the sub-screen drum 3 is equal to the casing 1 in length. During the screening process, the longer multi-stage screen drum can give the sand and gravel materials sufficient time to be stirred and fall, thereby ensuring that materials of different particle sizes fully fall to the corresponding falling areas.

[0038] As a technical solution of this embodiment, further, Figure 4 As shown, the driving assembly also includes a rack 304 circumferentially arranged on the outer wall of the two ends of the sub-screening cylinder 3, and the rack 304 is meshed with the transmission gear 8 in the gear compartment 104. This is the operation mode in which the transmission gear 8 drives the sub-screening cylinder 3. One side of the transmission gear 8 is coaxially connected to a third motor 801, and a transmission belt 802 is sleeved between the transmission gear 8 on the same side as the transmission gear 8 connected to the third motor 801. When the third motor 801 drives one of the transmission gears 8, during the movement of the secondary transmission gear 8, The transmission belt 802 on the other side drives the other transmission gear 8 on the same side to rotate, so that the transmission gears 8 on both sides of the same side drive the rack 304 at one end of the sub-screening cylinder 3, and the driving is more stable. The remaining two transmission gears 8 only serve as the supporting structure of the sub-screening cylinder 3, and the supports at the four corners are stable. When it is necessary to improve the rotation ability of the sub-screening cylinder 3, the two transmission gears 8 at the other end can be installed in the same way by connecting with the transmission belt 802 and driving with the third motor 801, so as to improve the screening and rotation ability of the sub-screening cylinder 3.

[0039] As a technical solution of this embodiment, further, the outer circumference of the transmission shaft 5 is protruded with a plurality of shaft seats 501 continuously arranged along the length of the transmission shaft 5, the shaft seat 501 is hollow inside and open at the upper end, and a positioning shaft 502 is arranged inside the shaft seat 501 between the left and right ends of the shaft seat 501, and the fan plate 6 is installed through the positioning shaft 502, and a positioning hole 603 is opened at the bottom of the fan plate 6. The fan plate 6 is swingably set on the positioning shaft 502 through the bottom positioning hole 603. The fan plate 6 is a plate-like structure with the same length as the positioning shaft 502. Because the fan plate 6 can be swingably set on the positioning shaft 502 through the positioning hole 603, when the other end of the fan plate 6 The brush head 7 is in contact with the outer surface of the sub-screening cylinder 3, and drives the fan plate 6 to swing upward when the sub-screening cylinder 3 is rotating, thereby avoiding the damage to the fan plate 6 caused by the direct relative friction between the fan plate 6 and the sub-screening cylinder 3 during the rotation process if the fan plate 6 is fixed. In severe cases, the fan plate 6 may be broken. The swinging setting can reduce the buffer in the relative motion state with the sub-screening cylinder 3. Since the fan plate is swingably mounted on the positioning shaft through the positioning hole, when a fan plate 6 passes through the sub-screening cylinder 3, the end of the fan plate provided with the brush head loses the friction force and contact with the sub-screening cylinder, so that the fan plate 6 falls naturally. The wind force generated during the falling process of the fan plate 6 can The dust generated in the casing 1 can be fanned into the cleaning bin 103 to avoid the accumulation of dust and fine particles in the equipment, thereby affecting the service life of the equipment. At the same time, a dust suction sponge can be built in the cleaning bin to absorb the dust entering the cleaning bin on the dust suction sponge body, so that it is more convenient for the staff to clean the cleaning bin later. They only need to pull out the dust suction sponge and clean it. The second motor 503 is coaxially connected to one end of the transmission shaft 5, and an installation groove 601 is opened on the outer side of the fan plate 6. A plurality of pin holes 602 are horizontally arranged on the front and rear plates of the installation groove 601. A brush head 7 is embedded in the installation groove 601, and the brush head 7 is connected to the fan plate 6. The fan plates 6 are of equal length, and a clamp 701 of the same length as the mounting groove 601 is provided on one side of the brush head 7. The brush head 7 is embedded in the mounting groove 601 through the clamp 701. The clamp 701 and the mounting groove 601 are fixedly connected by a pin provided in the pin hole 602, and the disassembly method is more convenient. Since the brush head 7 is used to brush the sand and gravel in the sieve hole, the wear of the brush head 7 is inevitable. This installation method improves the convenience of replacing the brush head 7 and saves manpower and material resources. During the material screening process, it can also eliminate a large amount of dust generated in the process, greatly reduce the spread of dust to a certain extent, achieve the purpose of curbing dust, and realize multiple functions at the same time.

[0040] Embodiment 2:

[0041] When the equipment is working, sand and gravel are filled into the upper opening of the feed bin 2. When the feeding auger 4 is in operation, the sand and gravel enter the sub-screening drum 3 through the feed bin 2. The rotatable sub-screening drum 3 is connected to the driving components at its front and rear ends through the transmission gears 8 arranged in the gear bins 104 on both sides of the casing 1 so as to be driven to rotate. At the same time, the feeding auger 4 extending from the feed bin 2 to the other end of the casing 1 rotates in the opposite direction thereto. After the sand and gravel enter the sub-screening drum 3, the rotating sieve drum and the rotating feeding auger 4 can not only ensure the gradual pushing of the sand and gravel from in to out to prevent the sand and gravel from accumulating in the sub-screening drum 3, but also the relative rotation of the sub-screening drum 3 and the feeding auger 4 can make the sand The stones are always kept in a scattered state, which reduces the probability of pressing the lower sand and gravel into the sieve holes due to the large amount of sand and gravel accumulation. During the rotation of the sub-screening drum 3, cleaning components with brush heads 7 on the outside are also provided in the cleaning bins 103 on both sides of the casing 1. The cleaning components rotate so that the brush heads 7 are close to the sub-screening drum 3, and the two rotate relatively. The brush heads 7 apply pressure to the surface of the passing sub-screening drum 3 to further knock down the sand and gravel stuck in the sieve holes to avoid clogging of the mesh. Finally, the fan plate 6 arranged on the outside of the transmission shaft 5 can swing during the rotation to fan the dust caused by the sand and gravel screened in the sub-screening drum 3 into the cleaning bin 103 to avoid the accumulation of dust in the bin body of the casing 1 and the impact on the service life.

[0042] The basic principles and main features of the present invention and the advantages of the present invention are shown and described above. For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention; therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is limited by the attached claims rather than the above description. Therefore, it is intended to include all changes within the meaning and scope of the equivalent elements of the claims in the present invention, and any figure marks in the claims should not be regarded as limiting the claims involved.

[0043] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A multi-stage concrete sand and gravel screening device, comprising a housing (1), characterized in that: It also includes a sub-screening cylinder (3), on the outer walls of the front and rear ends of the sub-screening cylinder (3), a driving assembly is circumferentially arranged, and the sub-screening cylinder (3) is rotatably arranged in the cavity of the casing (1) through the driving assembly; Four gear bins (104), the four gear bins (104) are arranged in pairs on the left and right sides of the front and rear ports of the housing (1), respectively, the gear bins (104) are conductively connected to the cavity of the housing (1), and the gear bins (104) are equipped with transmission gears (8) that are transmission-connected to the drive assembly; Two cleaning chambers (103), the two cleaning chambers (103) are connected to each other and are arranged at both sides of the casing (1) with equal lengths. A cleaning mechanism is built into the cleaning chamber (103). The cleaning mechanism comprises a plurality of fan plates (6) centered on the transmission shaft (5) and circumferentially arranged on the outside of the transmission shaft (5). A brush head (7) is arranged at the outer end of the fan plate (6). One end of the fan plate (6) with the brush head (7) is arranged close to the sub-screen cylinder (3). A feed bin (2), the upper end of which is open, one side of the feed bin (2) is conductively connected to one end of the casing (1), the other end of the casing (1) is provided with a discharge port (101), a feed auger (4) is arranged from one end of the outer side of the feed bin (2) to one end of the discharge port (101) and is horizontally arranged at the center axis of the sub-screening cylinder (3), one end of the feed auger (4) is coaxially connected to a first motor (401); A plurality of discharge bins (102) are evenly distributed at the lower end of the casing (1).

2. A multi-stage concrete sand and gravel screening device according to claim 1, characterized in that: The inner walls of the front and rear ports of the casing (1) are both circumferentially provided with a first concave slide groove (105), and the drive components at the front and rear ends of the sub-screen drum (3) are respectively embedded in the first slide groove (105). The bottom plates of the cleaning bins (103) on both sides of the casing (1) are arranged to be tilted downward, and an opening is arranged on the side of one end of the cleaning bin (103) tilted downward.

3. A multi-stage concrete sand and gravel screening device according to claim 2, characterized in that: The driving assembly comprises a second slide groove (301) provided on the outer wall of the front and rear ports of the sub-screen cylinder (3), the two second slide grooves (301) being arranged one-to-one corresponding to the first slide groove (105), a plurality of rollers (303) being evenly distributed around the inner circumference of the second slide groove (301), and a limit retainer (302) being arranged between the plurality of rollers (303).

4. A multi-stage concrete sand and gravel screening device according to claim 3, characterized in that: The limit retainer (302) is an annular structure with a plurality of limit holes evenly distributed on the outer surface, and the roller (303) is limit-embedded in the limit holes. The limit retainer (302) and the roller (303) are arranged between the first slide groove (105) and the second slide groove (301).

5. The multi-stage concrete sand and gravel screening device according to claim 1, characterized in that: The driving assembly further comprises a toothed track (304) circumferentially arranged on the outer walls of the two ends of the sub-screen cylinder (3), and the toothed track (304) is meshingly connected with a transmission gear (8) in a gear compartment (104).

6. The multi-stage concrete sand and gravel screening device according to claim 1, characterized in that: The outer circumference of the transmission shaft (5) is provided with a plurality of shaft seats (501) which are continuously arranged along the length of the transmission shaft (5); the shaft seat (501) is hollow inside and has an opening at one end away from the transmission shaft; a positioning shaft (502) is arranged inside the shaft seat (501) and is mounted between the left and right ends of the shaft seat (501); the fan plate (6) is installed via the positioning shaft (502); and one end of the transmission shaft (5) is coaxially connected to a second motor (503).

7. A multi-stage concrete sand and gravel screening device according to claim 6, characterized in that: The fan plate (6) has a positioning hole (603) at the bottom, and the fan plate (6) is swingably set on the positioning shaft (502) through the bottom positioning hole (603). The fan plate (6) has a mounting groove (601) at the outer side, and a plurality of pin holes (602) are transversely arranged on the front and rear plate surfaces of the mounting groove (601), and a brush head (7) is embedded in the mounting groove (601).

8. A multi-stage concrete sand and gravel screening device according to claim 7, characterized in that: The brush head (7) is of equal length to the fan plate (6), and a clamping piece (701) of equal length to the mounting groove (601) is provided on one side of the brush head (7). The brush head (7) is embedded in the mounting groove (601) via the clamping piece (701), and the clamping piece (701) and the mounting groove (601) are fixedly connected by a pin provided in the pin hole (602).

9. The multi-stage concrete sand and gravel screening device according to claim 1, characterized in that: The sub-screen drum (3) is a multi-stage screen drum structure, and the multi-stage screen drums are multi-stage structures with mesh sizes increasing from small to large from one end close to the feed bin (2) to one end of the discharge port (101). The multi-stage screen drums corresponding to the sub-screen drum (3) are arranged one by one in a plurality of discharge bins (102) arranged at the lower end of the casing (1), and the lower end of the discharge bin (102) is open.

10. The multi-stage concrete sand and gravel screening device according to claim 1, characterized in that: One side of one of the transmission gears (8) is coaxially connected to a third motor (801), and a transmission belt (802) is sleeved between the transmission gear (8) on the same side as the transmission gear (8) connected to the third motor (801).

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