CN211756249U

CN211756249U - Filter spraying device

Info

Publication number: CN211756249U
Application number: CN202020354938.4U
Authority: CN
Inventors: 陈庆平; 王益康; 陈积兰; 张林全; 方向; 陈锦锦; 姚潘姗
Original assignee: Zhejiang Lifeng Machinery Parts Co ltd
Current assignee: Zhejiang Lifeng Machinery Parts Co ltd
Priority date: 2020-03-19
Filing date: 2020-03-19
Publication date: 2020-10-27
Anticipated expiration: 2030-03-19

Abstract

The utility model discloses a filter spraying device, it includes the paint finishing and moulds powder recovery system, paint finishing includes one-way conveying assembly, spray gun, one-way conveying assembly includes conveying chain, carrier, the carrier is arranged on the conveying chain and the equidistance with rotation mode movable mounting on the conveying chain, the conveying chain passes moulds powder recovery system, the spray gun is located moulds in the powder recovery system and the spray regime of spray gun towards the carrier on the conveying chain. The filter spraying device promotes the plastic powder to be more uniformly distributed at each part of the shell of the filter by improving the rotation amount and the rotation angle of the carrier, and the uniformity of the shell spraying operation of the filter is effectively improved.

Description

Filter spraying device

Technical Field

The utility model relates to a filter spraying device.

Background

The surface of the filter is covered with a protective layer, so that the filter has an antirust protective effect and also has a more attractive appearance. The protective layer is processed by adopting a plastic spraying process, the filter spraying plastic powder in the prior art adopts the technology that a carrier is arranged on a circulating conveying path constructed by a chain, a shell of the filter to be processed is placed on the carrier, a spray gun is arranged at a specific working position, the shell of the filter can receive the plastic powder sprayed from the spray gun when the carrier carries the shell of the filter to pass through the spray gun, and finally a protective layer is formed on the shell of the filter. As the whole body of the shell of the filter is required to be sprayed with molding powder, all parts of the shell of the filter can enter the spraying range of the spray gun. The prior art, in order to guarantee that the casing of filter can both get into the spray regime of spray gun all around, generally adopt the top to spout the technique, be about to the spray gun setting in higher position, the vertical visual angle downwards that can all expose in vertical visual angle of down of the injection direction of spray gun, so adopt the top to spout the technique and can be with moulding the most surfaces of powder spraying at the casing of filter. However, molding powder is not available at the recessed features of the filter housing because these surface features cannot be found in vertically downward viewing angles. In order to further make up for the technical defects, the prior art also provides a technical scheme for enabling the carrier to rotate at the spraying station and spraying the plastic powder from the horizontal direction. The surface of the carrier in the technical scheme is provided with transmission teeth, the spraying station is provided with a spatial position fixing rack, when the carrier passes through the position of the rack, the transmission teeth on the carrier are meshed with the transmission teeth on the rack, and the carrier moves forwards and can rotate while moving forwards under the driving action of the rack. Although all parts of the shell of the filter can enter the spraying range of the spray gun through the technical scheme, the rotation amount of the carrier in the spraying range of the spray gun is very limited, and the rotation angle is less than two hundred and seventy degrees, so that the molding powder amount on one side of the shell of the filter is much more than that on other parts, and the uniform effect of molding powder spraying is poor.

Disclosure of Invention

The to-be-solved technical problem of the utility model is how to promote the homogeneity of the shell spraying operation of filter, obtain a filter spraying device from this.

In order to solve the technical problem, the utility model adopts the following technical scheme: the spraying device of the filter comprises a spraying system and a plastic powder recovery system, wherein the spraying system comprises a one-way conveying assembly and a spray gun, the one-way conveying assembly comprises a conveying chain and a carrier, the carrier is movably arranged on the conveying chain in a rotating mode and is arranged on the conveying chain at equal intervals, the conveying chain penetrates through the plastic powder recovery system, the spray gun is positioned in the plastic powder recovery system, the spraying range of the spray gun faces the carrier on the conveying chain, the side face of the carrier is provided with a transmission gear, the spraying system is further provided with an active rotating assembly, the active rotating assembly comprises a linear cylinder and a rack, the rack is fixedly connected with a piston rod of the linear cylinder, the moving direction of the rack driven by the linear cylinder is parallel to the conveying direction of the one-way conveying assembly, the rack body protrudes towards one side, the protruding part of the rack is provided with a transmission gear, and the moving range of the transmission gear of the carrier, the carrier is movably connected with the rack through meshing of the transmission teeth, the spray guns are distributed on two sides of the conveying chain and are annularly distributed in the same horizontal plane at equal angles, the spraying ranges of the spray guns are intersected in the same area, and the area is located in the movement range of the carrier.

After the active rotating assembly works, more rotating amount and rotating angle can be provided for the carrier in the original movement stroke of the carrier, and the shell of a filter positioned on the carrier can rotate more, which is a key assembly for obtaining uniform spraying; as for a single carrier, after the linear cylinder stretches and retracts to drive the rack, the carrier can rotate forwards and backwards, the rotation amount and the rotation angle can be increased by three times, and the angle of single rotation can exceed three hundred and sixty degrees. In the technical scheme, the distribution characteristics of the spray guns are not only positioned on one side of the carrier but distributed around the carrier, which is the main reason that the spray guns are annularly distributed at equal angles in the same horizontal plane, so that a better uniform spraying effect can be obtained; in addition, the spraying range of the spray gun faces to a fixed circle center position, the best air flow hedging effect can be achieved, and the plastic powder diffusion range can be reduced.

The adhesive capacity of the plastic powder can still normally play when the plastic powder is diffused in the air and moves along with the air flow, so that the plastic powder diffused in the air can be utilized to have positive significance for the shell of the filter on the carrier outside the spraying station. Therefore, the distribution length of the transmission teeth on the rack is set to be a value which is more than three times of the distance between the adjacent carriers, so that the rotation amount and the rotation angle of the carriers are greatly increased, and a small amount of diffused plastic powder can be uniformly received by rotating the shell of the filter on the carrier outside the spraying station.

The optimal arrangement of the spray guns is two on both sides of the conveying chain, namely the spacing angle of the annular distribution of the spray guns is ninety degrees.

This technical scheme has optimized moulding powder recovery system in order to can retrieve the moulding powder of diffusion so that the reutilization. The plastic powder recovery system comprises a floor type negative pressure bin, a steady flow conveying air duct, an air draft unit, a coarse grain collector and a fine dust collector, wherein a cavity is arranged in the floor type negative pressure bin, the bottom end of the floor type negative pressure bin is of an open structure, a conveying chain penetrates through the cavity, the motion range of a carrier is intersected with the cavity, the parts of a spray gun and a rack, which are provided with transmission teeth, are positioned in the cavity, the air draft unit is arranged at the top end of the floor type negative pressure bin, the air inlet end of the air draft unit is communicated with the cavity, the steady flow conveying air duct is of a straight tubular structure, the air draft unit is connected with one end of the steady flow conveying air duct, the air outlet end of the air draft unit is communicated with the interior of the steady flow conveying air duct, the other end of the steady flow conveying air duct is connected with the fine dust collector, the top end of the coarse grain collector is at least provided with three collecting channels, the central lines of the collecting channels are positioned in the vertical direction, the collecting channels are arranged straightly along the steady flow conveying air duct at intervals, one ends of the collecting channels are positioned below the steady flow conveying air duct and are communicated with the interior of the steady flow conveying air duct, a coarse grain storage cavity is arranged in the coarse grain collector, the other ends of the collecting channels are communicated with the coarse grain storage cavity, the bottom end of the coarse grain collector is provided with a coarse grain discharge hole which is communicated with the coarse grain storage cavity, the coarse grain collector is provided with a valve on the coarse grain discharge hole, a fine dust storage cavity is arranged in the fine dust collector, the top end of the fine dust collector is provided with an exhaust channel, the bottom end of the fine dust collector is provided with a fine dust discharge hole which is communicated with the interior of the steady flow conveying air duct, and the exhaust channel, the inside filter core that is equipped with of fine dust collector, the filter core is installed in exhaust passage, fine dust collector is equipped with the valve on the fine dust discharge gate.

The self-weight of the molding powder can force the molding powder to settle after floating until the molding powder falls to the ground or other supporting surfaces. The floor type negative pressure bin is used for covering the spraying operation area and sealing the spraying operation area in the cavity, so that the range of the plastic powder diffused in the air can be limited to the minimum range. The steady flow conveying air duct has a narrow inner space, so that the whole molding powder recovery system needs a certain floor space, and sufficient implementation conditions can be obtained in the industrial application field. The steady flow conveying air duct is obliquely arranged, so that the inner space of the steady flow conveying air duct is obliquely distributed; for the flowing air current, the process of moving in the steady flow conveying air duct is the climbing process, and based on the long and narrow characteristic of the steady flow conveying air duct, the time required by the air current for climbing is not short, the self-descending phenomenon of the plastic powder can be gradually shown in the climbing process, and particularly, the self-descending phenomenon of the plastic powder occurs in the middle climbing period from the beginning. The coarse grain collector is arranged in the middle of the steady flow conveying air duct, the coarse grain plastic powder is just positioned at the position of the collecting channel in the middle climbing stage, and the self-descending coarse grain plastic powder naturally falls into the coarse grain storage cavity. In the technical scheme, a plurality of collecting channels are arranged instead of a single collecting channel with a large opening, so that airflow stall is mainly avoided, and the width of an airflow flowing area is suddenly increased and the air pressure is reduced due to the adoption of the structure of the single collecting channel with the large opening, so that the flowing speed is reduced, and turbulent flow is generated to drive the coarse plastic powder to separate from the area where the coarse plastic collector is located. The long and narrow characteristic of the steady flow conveying air duct is designed to enable airflow to flow more stably, if coarse plastic powder is not separated and enters the fine dust collector, the secondary utilization efficiency of the plastic powder is affected, and after all, the adhesive force of the coarse plastic powder is weaker than that of the fine plastic powder. Finally, the airflow separated from coarse particles by self-descending enters a fine dust collector, the inner surface of the fine dust collector in the fine dust storage cavity is large enough to be used for attaching a large amount of fine molding powder, and then the molding powder convenient for secondary utilization is collected in the fine dust collector. And the air filtered by the filter element can be directly discharged to the outside. The collected coarse plastic powder and the collected fine plastic powder can be output in a centralized way after being accumulated, and then can be used for the operation of spraying plastic powder on a filter, so that secondary utilization is realized.

In order to further ensure that the collection channel does not generate turbulent flow on the airflow in the steady flow conveying air duct and ensure that the self-descending process of the molding powder is smoothly carried out, the width of the end, communicated with the interior of the steady flow conveying air duct, of the collection channel is gradually reduced from top to bottom.

In order to improve the self-reduction efficiency of the plastic powder in the steady flow conveying air duct and fully ensure that the plastic powder self-reduction occurs at the position of the collecting channel, the width of the steady flow conveying air duct is gradually increased from bottom to top.

The utility model adopts the above technical scheme: the filter spraying device promotes the plastic powder to be more uniformly distributed at each part of the shell of the filter by improving the rotation amount and the rotation angle of the carrier, and the uniformity of the shell spraying operation of the filter is effectively improved.

Drawings

The present invention will be described in further detail with reference to the accompanying drawings and embodiments.

FIG. 1 is a schematic view of a spray coating apparatus for a filter according to the present invention;

fig. 2 is a schematic structural view of a one-way conveying assembly of a filter spraying device according to the present invention;

fig. 3 is a schematic view of the one-way conveying assembly of the spraying device for a filter according to the present invention.

Detailed Description

The filter spraying device comprises a spraying system and a molding powder recovery system. The spraying system is used for spraying molding powder to a shell of the filter to be processed. The molding powder recovery system is used for collecting the molding powder diffused into the air from the spraying system.

As shown in fig. 1, the molding powder recovery system comprises a floor type negative pressure bin 1, a steady flow conveying air duct 3, an air draft unit 4, a coarse particle collector 5 and a fine dust collector 9.

The floor type negative pressure bin 1 is a hollow shell structure formed by welding metal plates, the middle of a body of the floor type negative pressure bin is a cavity 2, an opening is formed in the bottom of the body, and the cavity 2 is directly communicated with the outside through the opening to form a semi-closed structure; the body is provided with two symmetrical notches with the same structure, and the notches are used for enabling the carrier 16 on the circulating conveying path to carry the shell of the filter to enter the cavity 2 through the spraying system. The edge of body bottom is straight to be convenient for the body directly be connected with ground, make cavity 2 no longer through opening and external intercommunication, place subaerial through the bottom of body in the actual production process. The inner cavity 2 of the floor type negative pressure cabin 1 is communicated with the outside only through a gap.

The extraction unit 4 comprises a housing and a fan. The shell is hollow, two ends of the shell are respectively provided with an opening, the electric fan is arranged in the shell, a unidirectional flowing airflow flow path can be established in the shell after the electric fan is electrified, and an air inlet end is formed at one opening of the shell and an air outlet end is formed at the other opening of the shell. The air draft unit 4 is arranged at the top end of the floor type negative pressure cabin 1, a shell of the air draft unit 4 is connected with the body of the floor type negative pressure cabin 1, and an air inlet end of the air draft unit 4 is communicated with the cavity 2 of the floor type negative pressure cabin 1.

The steady flow air conveying duct is of a straight tubular structure, the air exhaust unit 4 is connected with one end of the steady flow air conveying duct 3, the air outlet end of the air exhaust unit 4 is communicated with the inside of the steady flow air conveying duct 3, and the other end of the steady flow air conveying duct 3 is connected with the fine dust collector 9. The space posture of the steady flow conveying air duct 3 is in an inclined state, and one end of the steady flow conveying air duct 3 is higher than the other end of the steady flow conveying air duct 3. The width of the interior of the stationary flow conveying duct 3 is not the same everywhere, but gradually increases from bottom to top.

The fine dust collector 9 is of a hollow shell structure, a fine dust storage cavity 10 is arranged in the middle of the interior of the fine dust collector 9, an exhaust passage 11 is arranged at the top end of the fine dust collector 9, a fine dust discharge hole 12 is arranged at the bottom end of the fine dust collector 9, the exhaust passage is communicated with the fine dust storage cavity 10, and the fine dust storage cavity 10 is communicated with the fine dust discharge hole 12. The fine dust storage cavity 10 is directly communicated with the interior of the steady flow conveying air duct 3; the exhaust channel 11 and the fine dust discharge port 12 are directly communicated with the fine dust storage chamber 10. A filter element 13 is arranged in the fine dust collector 9, and the filter element 13 is arranged in the exhaust passage 11; in order to facilitate the control, the fine dust collector 9 is provided with a valve at the fine dust outlet 12, and the valve is closed in an initial state.

The coarse grain collector 5 is also of a hollow shell structure; the top end of the coarse grain collector 5 is provided with three collecting channels 6, the middle part inside the coarse grain collector 5 is provided with a coarse grain storage cavity 7, the bottom end of the coarse grain collector 5 is provided with a coarse grain discharge hole 8, the collecting channels 6 are communicated with the coarse grain storage cavity 7, and the coarse grain storage cavity 7 can be communicated with the outside through the coarse grain discharge hole 8. The coarse grain storage cavity 7 is in an inverted conical structure. In order to facilitate control, the coarse grain collector 5 is provided with a valve at the coarse grain discharge port 8, and the valve is closed in an initial state. The coarse grain collector 5 is positioned below the steady flow air supply channel, and the coarse grain collector 5 is arranged in the middle of the steady flow conveying air duct 3. After installation, the central lines of the collecting channels 6 are all located in the vertical direction, and the collecting channels 6 are arranged straightly at intervals along the steady flow conveying air duct 3. One end of the collecting channel 6 is positioned below the steady flow conveying air duct 3, the collecting channel 6 is communicated with the interior of the steady flow conveying air duct 3, and the other end of the collecting channel 6 is communicated with the coarse grain storage cavity 7; the width of the end of the collecting channel 6 communicated with the interior of the steady flow conveying air duct 3 is gradually reduced from top to bottom.

As shown in fig. 2 and 3, the spray coating system includes a one-way delivery assembly 14, a spray gun 20, and an active rotating assembly.

The unidirectional conveying assembly 14 comprises a conveying chain 15, a carrier 16, a frame, a motor and a speed changer. The conveying chain 15 is installed on the frame through two chain wheels, the conveying chain 15 is unfolded in the horizontal direction to form an annular structure, two ends of the conveying chain 15 are semicircular, and the middle part of the conveying chain 15 is a straight structure. The motor and the transmission are both mounted on the frame, an output shaft of the motor is fixedly connected with an input shaft of the transmission, and an output shaft of the transmission is connected with one of the chain wheels. After the motor is started, the chain wheel rotates, and then the conveying chain 15 is driven to operate. The conveyor chain 15 runs unidirectionally in one direction only. The carrier 16 comprises a base 17, a rotating shaft 18 and a supporting sleeve 19, wherein one base 17 is fixedly connected with only one chain link of the conveying chain 15, the rotating shaft 18 is movably arranged on the base 17 through a bearing, the supporting sleeve 19 is fixedly connected with one end of the rotating shaft 18, and the central line of the supporting sleeve 19 is superposed with the central line of the rotating shaft 18; a sliding block for supporting the base 17 is further arranged on the rack of the unidirectional conveying assembly 14, and the supporting base 17 is connected with the sliding block in a sliding manner; the supporting sleeve 19 is a circular truncated cone-shaped structure, and the bottom edge of the side surface of the supporting sleeve is provided with a transmission gear. The support sleeve 19 can rotate on the conveyor chain 15 relative to the base 17 and the conveyor chain 15, and all the carriers 16 are arranged at equal intervals. When the motor is started to drive the conveying chain 15 to run, the carrier 16 rotates on the horizontal plane. In the painting system there are four spray guns 20, one on each side of the straight section of one of the conveyor chains 15, i.e. two spray guns 20 on each side. The spray guns 20 are fixed on the frame of the unidirectional conveying assembly 14, and the four spray guns 20 are installed at the same height and are positioned in the same horizontal plane. The spray guns 20 on the two sides are symmetrically distributed relative to the straight part of the conveying chain 15, and the distances from the two spray guns 20 on the same side to the straight part of the conveying chain 15 are the same; the distances between the adjacent spray guns 20 are the same among the four spray guns 20; the spraying ranges of the spray guns 20 are all towards one of the areas of the range of the carrier 16 moving along with the conveying chain 15, namely the spraying ranges of the spray guns 20 intersect in the area, the distance from the carrier 16 to each spray gun 20 is the same when the carrier 16 enters the area, the area is taken as the center, the four spray guns 20 are distributed in an annular shape with equal angles, and the interval angle of the annular distribution of the spray guns 20 is ninety degrees, as shown in fig. 3.

The active rotating assembly comprises a linear cylinder and a rack 21. The linear cylinder is fixedly arranged on the frame of the one-way conveying assembly 14. The rack 21 is fixedly connected with a piston rod of the linear cylinder. The rack 21 is movably mounted on the frame of the unidirectional conveying assembly 14 in a sliding manner, and the rack 21 can slide in the horizontal direction. The rack 21 is positioned outside one straight part of the conveying chain 15 of the unidirectional conveying assembly 14, when the linear air cylinder drives the rack 21 to move, the moving direction of the rack 21 is parallel to the straight part of the conveying chain 15 of the unidirectional conveying assembly 14, and the moving direction of the rack 21 is parallel to the conveying direction of the unidirectional conveying assembly 14 due to the unidirectional movement of the conveying chain 15. One side of the rack 21 protrudes outwards, the rack 21 is provided with transmission teeth at the protruding part, and the distribution length of the transmission teeth on the rack 21 is larger than three times of the distance between the adjacent carriers 16. After the carrier 16 passes through the area near the rack 21, the transmission teeth on the carrier 16 can be meshed with the transmission teeth on the rack 21, namely, the movement range of the transmission teeth of the carrier 16 is intersected with the movement range of the transmission teeth of the rack 21, the carrier 16 is movably connected with the rack 21 through the meshing of the transmission teeth, the rack 21 is pushed by a linear cylinder to move in a translation mode, the absolute value of the translation speed of the rack 21 is far larger than the absolute value of the movement speed of the carrier 16, the interaction amount between the rack 21 and the carrier 16 is increased, a housing of a filter positioned at the intersection area of the injection range of the spray gun 20 can obtain more rotation amount and rotation angle, and the rotation angle can exceed three hundred sixty degrees. The linear cylinder contracts in the initial state. The conveying chain 15 penetrates through the floor type negative pressure cabin 1 body through a gap embedded in the floor type negative pressure cabin 1 body, so that a straight part at one position of the conveying chain 15 is always positioned in the cavity 2, and the carrier 16 can also enter the cavity 2 after moving along with the conveying chain 15; in addition to this, the lance 20 and the portion of the rack 21 provided with the gearing are located in the cavity 2.

When the spraying device is used, a shell of a filter waiting for plastic powder spraying operation is placed on the carrier 16, the carrier 16 moves forwards on a one-way circulation path, and after the shell of the filter enters the working range of the spray gun 20, plastic powder spraying operation is performed. When the gear teeth outside the support sleeve 19 of the carrier 16 start to engage with the gear teeth on the rack 21 of the active rotary assembly, the rack 21 can enter into a rapid translational motion, and each time the rack 21 establishes a connection with the carrier 16 and drives the housing of the filter on the carrier 16 to rotate. Since the absolute value of the translation speed of the rack 21 is much greater than the absolute value of the translation speed of the carrier 16, that is, the housing of the filter, the carrier 16 is continuously driven by the rack 21 to rotate the housing of the filter until the carrier 16 moves away from the rack 21 and the rotation is stopped while the rack 21 and the carrier 16 can be connected. The filter housing during autorotation just passes into the intersection of the spray range of the spray gun 20. The gun 20 continuously sprays molding powder toward the filter housing, and sufficient autorotation ensures that all parts of the filter housing surface can be evenly covered with molding powder. After the filter-carrying housing of the carrier 16 leaves the intersection of the spray range of the spray gun 20, the filter housing has completed the powder spray operation.

In the process, the plastic powder recovery system is always in a working state, and the air draft unit 4 works, so that an environment with the pressure lower than the external pressure can be established inside the floor type negative pressure cabin 1. In this way, the molding powder diffused in the floor type negative pressure chamber and not adhered to the surface of the housing of the filter cannot flow to the outside of the floor type negative pressure chamber 1. The diffused plastic powder moves from bottom to top along with the airflow and enters the steady flow conveying air duct 3 after passing through the air draft unit 4. Because the steady flow conveying air duct 3 is obliquely arranged, the airflow is in a climbing motion state in the steady flow conveying air duct 3. The air current carries wind channel 3 internal motion at the stationary flow, along with high increase, the inside width in stationary flow transport wind channel 3 increases gradually, and air current velocity of motion slows down for the coarse grain plastic powder of diffusion in the air descends at self gravity influence, and the coarse grain plastic powder can fall in collection passageway 6 place region, and final coarse grain plastic powder falls into coarse grain storage chamber 7 in, the plastic powder that distributes at the air afterwards only remains the fine plastic powder. The airflow enters the fine dust collector 9 after climbing to the highest position, and because the inner space of the fine dust collector 9 is larger and the inner surface of the fine dust collector 9 is larger, the fine plastic powder in the airflow can be attached and deposited in the fine dust storage cavity 10 in a state of slower flow speed; the air flow is filtered by the filter element 13 and discharged outwards. The molding powder gathered in the coarse particle storage cavity 7 and the fine dust storage cavity 10 can be discharged outwards by opening the valve, so that the purpose of molding powder by secondary utilization is facilitated.

Claims

1. A filter spraying device, filter spraying device includes paint finishing and moulds powder recovery system, paint finishing includes one-way conveyor assembly (14), spray gun (20), one-way conveyor assembly (14) includes conveying chain (15), carrier (16) with rotation mode movable mounting on conveying chain (15) and equidistance range is arranged on conveying chain (15), conveying chain (15) pass mould powder recovery system, spray gun (20) are located mould powder recovery system and spray gun (20) spray range is towards carrier (16) on conveying chain (15), its characterized in that: the side surface of the carrier (16) is provided with a transmission gear, the spraying system is also provided with an active rotating component, the active rotating assembly comprises a linear cylinder and a rack (21), the rack (21) is fixedly connected with a piston rod of the linear cylinder, the linear cylinder drives the rack (21) to move in a direction parallel to the conveying direction of the one-way conveying assembly (14), the rack (21) body protrudes to one side, the protruding part of the rack (21) is provided with a transmission gear, the movement range of the transmission gear of the carrier (16) is intersected with the movement range of the transmission gear of the rack (21), the carrier (16) is movably connected with the rack (21) through the meshing of transmission teeth, the spray guns (20) are distributed on two sides of the conveying chain (15) and the spray guns (20) are distributed annularly at equal angles in the same horizontal plane, the spray ranges of the spray guns (20) intersect in the same area and the area is located within the range of motion of the carrier (16).

2. A filter spray coating device as claimed in claim 1, wherein: the distribution length of the transmission teeth on the rack (21) is more than three times of the distance between the adjacent carriers (16).

3. A filter spray coating device as claimed in claim 1, wherein: the spacing angle of the annular spray guns (20) is ninety degrees.

4. A filter spray coating device as claimed in claim 1, wherein: the plastic powder recovery system comprises a floor type negative pressure bin (1), a steady flow conveying air duct (3), an air draft unit (4), a coarse grain collector (5) and a fine dust collector (9), wherein a cavity (2) is arranged inside the floor type negative pressure bin (1), the bottom end of the floor type negative pressure bin (1) is of an open structure, a conveying chain (15) penetrates through the cavity (2), the movement range of a carrier (16) is intersected with the cavity (2), the positions of a spray gun (20) and a rack (21) which are provided with transmission teeth are both positioned in the cavity (2), the air draft unit (4) is arranged at the top end of the floor type negative pressure bin (1), the air inlet end of the air draft unit (4) is communicated with the cavity (2), the steady flow conveying air duct (3) is of a straight tubular structure, and the air draft unit (4) is connected with one end of the steady flow conveying air duct (3, the air outlet end of the air draft unit (4) is communicated with the inside of the steady flow conveying air duct (3), the other end of the steady flow conveying air duct (3) is connected with the fine dust collector (9), the steady flow conveying air duct (3) is obliquely arranged, the coarse grain collector (5) is installed in the middle of the steady flow conveying air duct (3), at least three collecting channels (6) are arranged at the top end of the coarse grain collector (5), the central lines of the collecting channels (6) are located in the vertical direction, the collecting channels (6) are vertically arranged along the steady flow conveying air duct (3) at intervals, one ends of the collecting channels (6) are located below the steady flow conveying air duct (3), the collecting channels (6) are communicated with the inside of the steady flow conveying air duct (3), the storage cavity (7) is arranged inside the coarse grain collector (5), and the other ends of the collecting channels (6) are communicated with the coarse grain storage cavity (7), the bottom end of the coarse grain collector (5) is provided with a coarse grain discharge hole (8), the coarse grain discharge hole (8) is communicated with a coarse grain storage cavity (7), the coarse grain collector (5) is provided with a valve at a coarse grain discharge hole (8), a fine dust storage cavity (10) is arranged inside the fine dust collector (9), an exhaust passage (11) is arranged at the top end of the fine dust collector (9), a fine dust discharge hole (12) is arranged at the bottom end of the fine dust collector (9), the fine dust storage cavity (10) is communicated with the interior of the steady flow conveying air duct (3), the exhaust channel (11) and the fine dust discharge hole (12) are communicated with the fine dust storage cavity (10), a filter element (13) is arranged in the fine dust collector (9), the filter element (13) is arranged in the exhaust passage (11), and a valve is arranged on the fine dust discharge hole (12) of the fine dust collector (9).

5. A filter sprayer according to claim 4, wherein: the width of the end of the collecting channel (6) communicated with the interior of the steady flow conveying air duct (3) is gradually reduced from top to bottom.

6. A filter sprayer according to claim 4, wherein: the width of the interior of the steady flow conveying air duct (3) is gradually increased from bottom to top.