CN212688174U

CN212688174U - Coating cavity and powder coating device

Info

Publication number: CN212688174U
Application number: CN202021882143.7U
Authority: CN
Inventors: 李翔; 邹嘉宸; 王荣; 黎微明
Original assignee: Jiangsu Leadmicro Nano Technology Co Ltd
Current assignee: Jiangsu Leadmicro Nano Technology Co Ltd
Priority date: 2020-09-01
Filing date: 2020-09-01
Publication date: 2021-03-12
Anticipated expiration: 2030-09-01

Abstract

The utility model relates to a powder coating device and coating film cavity fills into fluidization gas from the inlet port, can make the powder obtain higher initial velocity and fluidization. The area of the overflowing section of the inner cavity tends to increase in the direction from the air inlet port to the air outlet port. According to the fluid equation, the gas flow rate in the direction from the inlet port to the outlet port will have a decreasing trend. When the flow rate drops to a certain extent, the lifted powder will gradually start to settle and be lifted again when approaching the inlet port. Thus, the powder will form an internal circulation within a limited height, thereby increasing the interaction between the powder particles and reducing agglomeration. Meanwhile, the powder can be prevented from touching and being adsorbed on the air outlet port due to the limited lifting height of the powder. Furthermore, the powder forming the internal circulation increases the impact on the chamber wall and also reduces the powder adsorbed on the chamber wall. Therefore, the uniformity of the coating film is remarkably improved.

Description

Coating cavity and powder coating device

Technical Field

The utility model relates to a coating film technical field, in particular to coating film cavity and powder coating device.

Background

The surface functionalization of powder particles is an important component of a material surface engineering technology, and especially has important significance for improving the original performance of the particles. The surface functionalization of the powder particles can be realized by coating the surface of the powder particles with a layer, namely coating.

The ald technology has been widely used in the powder particle coating process because of its excellent uniformity, conformality and size controllability. In the current stage of the coating process, the adopted equipment is the fluidized bed ALD (Atomic layer deposition) equipment. Fluidized bed ALD equipment requires continuous pumping of the reaction chamber and charging of the fluidizing gas. In this way, the powder particles in the reaction chamber will be fluidized and dispersed.

However, the dispersed powder particles are often adsorbed on the inner wall or the port of the reaction chamber, so that the contact area between some particles and the particles cannot be effectively coated. Particularly, when a large amount of powder particles are subjected to film coating treatment, the uniformity of deposition is poor, so that the uniformity of final film coating is poor.

SUMMERY OF THE UTILITY MODEL

Accordingly, there is a need to provide a coating chamber and a powder coating apparatus that can improve the uniformity of coating.

The utility model provides a coating film cavity, includes interior cavity, the axial both ends of interior cavity are formed with inlet port respectively and give vent to anger the port, treat the powder of coating film can hold in interior cavity is close to inlet port's one end, and by inlet port arrives in the direction of the port of giving vent to anger, the cross-sectional area that overflows of interior cavity is the trend of increase.

In one embodiment, the inner cavity includes a first straight pipe section, a second straight pipe section and a tapered pipe section, the inner diameter of the first straight pipe section is smaller than the inner diameter of the second straight pipe section, the first straight pipe section and the second straight pipe section are respectively communicated with the small end and the large end of the tapered pipe section, the air inlet port and the air outlet port are respectively arranged on the first straight pipe section and the second straight pipe section, and the powder to be coated can be accommodated in the first straight pipe section.

In one embodiment, the taper angle of the tapered tube section is 10 to 140 degrees.

In one embodiment, the gas outlet device further comprises an outer cavity, the inner cavity is contained in the outer cavity, the gas outlet port is communicated with the outer cavity, and an exhaust port is formed at one end, far away from the gas outlet port, of the outer cavity.

In one embodiment, the device further comprises a vibration mechanism which can drive the inner cavity to vibrate.

In one embodiment, the apparatus further comprises a vibration mechanism capable of driving the inner cavity to vibrate relative to the outer cavity, wherein the vibration mechanism comprises:

a vibration source;

the connecting rod penetrates through the outer cavity, and two ends of the connecting rod are respectively fixedly connected with the outer wall of the inner cavity and the vibration source; and

the bellows, the cover is located the connecting rod, the both ends of bellows respectively with the outer wall of interior cavity reaches the inner wall sealing connection of outer cavity.

A powder coating apparatus comprising:

the coating chamber according to any one of the above preferred embodiments;

the gas path system is communicated with the gas inlet port and is used for filling gas into the inner cavity;

the heating system is used for heating the film coating cavity and the gas path system; and

and the air exhaust mechanism is communicated with the coating cavity and exhausts the inner cavity through the air outlet port.

In one embodiment, the coating device further comprises an exhaust gas treatment mechanism arranged between the air exhaust mechanism and the coating cavity.

In one embodiment, the air exhaust mechanism can exhaust air from the inner cavity at an adjustable air exhaust rate.

In one embodiment, the air pumping mechanism comprises a vacuum pump and a butterfly valve arranged between the vacuum pump and the coating cavity.

In one embodiment, the pumping mechanism comprises a vacuum pump, and an exhaust bypass which is connected with the vacuum pump in parallel and can be opened or closed, wherein the exhaust rate of the exhaust bypass is smaller than the pumping rate of the vacuum pump.

The powder coating device and the coating cavity are filled with the fluidizing gas from the gas inlet port, so that the powder can obtain higher initial speed and be fluidized. The area of the overflowing section of the inner cavity tends to increase in the direction from the air inlet port to the air outlet port. According to the fluid equation, the gas flow rate in the direction from the inlet port to the outlet port will have a decreasing trend. When the flow rate drops to a certain extent, the lifted powder will gradually start to settle and be lifted again when approaching the inlet port. Thus, the powder will form an internal circulation within a limited height, thereby increasing the interaction between the powder particles and reducing agglomeration. Meanwhile, the powder can be prevented from touching and being adsorbed on the air outlet port due to the limited lifting height of the powder. Furthermore, the powder forming the internal circulation increases the impact on the chamber wall and also reduces the powder adsorbed on the chamber wall. Therefore, the uniformity of the coating film is remarkably improved.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic view of a powder coating apparatus according to a preferred embodiment of the present invention;

FIG. 2 is a schematic structural diagram of an inner cavity of a coating chamber in the powder coating apparatus shown in FIG. 1;

FIG. 3 is a simulation of the airflow velocity distribution within the interior cavity shown in FIG. 2;

fig. 4 is a graph of the relationship between the intake air amount and the height of the splash zone at different pressures in the inner cavity shown in fig. 2.

Detailed Description

In order to make the above objects, features and advantages of the present invention more comprehensible, embodiments of the present invention are described in detail below with reference to the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein, as those skilled in the art will be able to make similar modifications without departing from the spirit and scope of the present invention.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", and the like, indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be construed as limiting the present invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," and "fixed" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.

In the present application, unless expressly stated or limited otherwise, the first feature may be directly on or directly under the second feature or indirectly via intermediate members. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like as used herein are for illustrative purposes only and do not denote a unique embodiment.

Referring to fig. 1, the present invention provides a powder coating apparatus 10 and a coating chamber 100. The powder coating device 10 includes a coating chamber 100, a gas path system 200, a heating system 300, and an air pumping mechanism 400.

A reaction cavity is formed in the coating cavity 100 for allowing the powder to be coated, such as micro-nano particles, to react and obtain a coating layer coated on the surface of the powder particles. The coating chamber 100 may have a single-layer chamber structure or a double-layer chamber structure.

Referring to fig. 2, the coating chamber 100 of the preferred embodiment of the present invention includes an inner chamber 110. The reaction chamber is formed inside the inner chamber 110. Moreover, an air inlet (not shown) and an air outlet (not shown) are formed at two axial ends of the inner cavity 110, respectively, and the powder to be coated can be accommodated at one end of the inner cavity 110 close to the air inlet. The gas inlet port and the gas outlet port are generally provided with filter screens, and the filter screens can allow precursors and purge gas to pass through and can block powder particles to be coated. In addition, the air inlet port and the air outlet port can be provided with air receiving flanges.

Further, the area of the flow cross section of the inner cavity 110 tends to increase in the direction from the inlet port to the outlet port. The flow cross section refers to the flow surface when the airflow flows from the air inlet port to the air outlet port. I.e., a cross-section taken in a direction perpendicular to the axial direction of the inner chamber 110. The area of the flow cross section can be continuously increased or gradually increased.

The gas circuit system 200 is in communication with the gas inlet port and is used to fill the interior of the inner chamber 110 with gas. The gas circuit system 200 generally includes a process gas circuit and a fluidization gas circuit for filling the precursor, the purge gas, and the fluidization gas, respectively, into the inner cavity 110. Gas circuit system 200 may be arranged as is known in the art. For example, the process gas circuit in the gas circuit system 200 includes a process gas pipeline, a source bottle connected to the process gas pipeline, a gas mass flow controller, and the like. The fluidizing gas path comprises a pulse valve, a gas mass flow controller and a fluidizing gas pipeline. The source bottle is used for containing a liquid or solid precursor source, and the gas mass flow controller is used for introducing a precursor with a specified flow into the reaction cavity. The function of only introducing nitrogen (i.e., purge gas) can be realized by opening a pneumatic valve (not shown) on the source bottle to allow the nitrogen purge gas to carry the precursor into the inner cavity 110 and closing the pneumatic valve on the source bottle. If a plurality of precursors are needed to be provided for the reaction cavity, a plurality of process gas pipelines can be arranged according to the actual needs of the process production. In addition, a pulse valve can be arranged on the process gas pipeline and used for controlling various precursors to alternately enter the reaction cavity.

The heating system 300 is used for heating the film coating chamber 100 and the gas path system 200. The heating system 300 may be an electrical heating assembly, generally comprising two parts. Wherein, one part can be an electric heating sheet structure coated outside the film coating cavity 100, and the heat can be conducted into the reaction cavity by electrifying and heating; the other part is a soft-packaged heating belt which can be wrapped on the pipeline of the gas circuit system 200 and the source bottle. The heating system is primarily used to maintain the reaction chamber at a suitable temperature, typically 40 ℃ to 350 ℃.

In order to accurately control the temperature in the reaction chamber, a temperature measuring terminal 140 is further disposed on the coating chamber 100. The temperature measuring terminal 140 is used for monitoring the temperature in the inner cavity 110 and displaying the temperature through a display screen arranged outside the film coating cavity 100.

The air-extracting mechanism 400 is communicated with the coating chamber 100, and extracts air from the inner chamber 110 through the air outlet port. The pumping mechanism 400 is used to evacuate the reaction chamber, thereby ensuring the isolation of the reaction region from air. The pumping mechanism 400 may be a vacuum pump, an exhaust valve, or the like.

Specifically, in the present embodiment, the powder coating device 10 further includes an exhaust gas treatment mechanism 500 disposed between the air exhaust mechanism 400 and the coating chamber 100. When the air pumping mechanism 400 pumps air, the tail gas of the reaction chamber is pumped into the tail gas treatment mechanism 500, and then a certain amount of air is charged to react with the tail gas to generate harmless particles.

The flow of the powder coating device 10 for performing the coating process is as follows:

powder to be coated is put into the inner cavity 110; the pumping mechanism 400 is started to pump the reaction chamber to vacuum, thereby maintaining effective isolation of the reaction chamber from the air environment; starting the heating system 300 to heat so as to enable the reaction cavity to reach the appropriate temperature required by the reaction; starting the gas path system 200, introducing fluidizing gas into the reaction cavity to fluidize and fully disperse the powder particles; then introducing a first precursor into the reaction cavity, and enabling the first precursor to be adsorbed on the surfaces of the powder particles; introducing purge gas to remove redundant first precursors in the reaction cavity; introducing a second precursor into the reaction cavity, and reacting the second precursor with the first precursor adsorbed on the surfaces of the powder particles to form a coating layer; and introducing purge gas to remove the redundant second precursor in the reaction cavity.

The above steps can be repeated, if necessary, until the thickness of the obtained clad layer is sufficient.

In the process of introducing fluidizing gas into the reaction chamber and fluidizing the powder particles by the gas circuit system 200, the powder particles first obtain a large initial velocity near the gas inlet port and quickly splash toward the gas outlet port. According to the fluid mechanics principle, on the premise of a certain flow, the smaller the flow cross section is, the larger the flow velocity is. Therefore, the flow rate of the gas will have a decreasing trend in the direction from the inlet port to the outlet port. When the fluidized powder splashes toward the gas outlet port and the flow rate drops to a certain extent, the pressure difference will be insufficient to support the powder. At this point, the kicked up powder will gradually begin to settle and be kicked up again as it approaches the inlet port. With this, the powder will form an internal circulation within the limited height of the internal cavity 110, thereby increasing the interaction between the powder particles and reducing agglomeration.

Meanwhile, the powder can be prevented from touching and being adsorbed on the air outlet port due to the limited lifting height of the powder, so that the air outlet port is prevented from being blocked or a large amount of powder is prevented from being adsorbed on a filter screen of the air outlet port. Furthermore, the powder forming the internal circulation increases the impact on the wall of the internal cavity 110 and also reduces the amount of powder adsorbed on the wall. Therefore, the uniformity of the coating film is remarkably improved.

In this embodiment, the pumping mechanism 400 can pump the inner cavity 110 at an adjustable pumping rate. When the first precursor and the second precursor are filled into the reaction chamber, the air intake rate in the reaction chamber can be made greater than the air exhaust rate by reducing the air exhaust rate of the air exhaust mechanism 400. In this way, a higher pressure will be maintained in the reaction chamber.

After the pressure in the reaction cavity rises, on one hand, the precursor can be prevented from being sucked away before adsorption or reaction, and the retention time of the precursor in the reaction cavity is prolonged, so that the surface of the powder is ensured to have sufficient adsorption reaction, and the waste is reduced. On the other hand, the pressure difference between the suction side (outlet port) and the inlet side (inlet port) can be reduced, and the height of the splashing zone when the powder is fluidized can be effectively controlled. Therefore, the phenomenon that the adsorption and removal of the precursor are influenced due to the fact that a large amount of powder is adsorbed on the air exhaust side can be prevented, and the growth efficiency of the coating layer is improved.

As shown in fig. 4, the higher the pressure in the reaction chamber, the lower the height of the powder splash zone is, with the same inlet gas flow rate.

When the purge gas is introduced and used to remove the excess precursor, the pumping rate of the pumping mechanism 400 can be increased. Therefore, the redundant precursors can be rapidly removed, and the coating efficiency is improved.

There are many ways to achieve adjustments to the pumping rate of the pumping mechanism 400. Such as:

referring to fig. 1 again, in the present embodiment, the air-extracting mechanism 400 includes a vacuum pump 410 and a butterfly valve 420 disposed between the vacuum pump 410 and the coating chamber 100. Since the power of the vacuum pump 410 is constant after it is started. Therefore, by controlling the opening degree of the butterfly valve 420, the air exhaust rate of the whole air exhaust mechanism 400 can be adjusted.

Another example is as follows:

in another embodiment, the pumping mechanism 400 comprises a vacuum pump, and an exhaust bypass (not shown) connected in parallel with the vacuum pump and capable of being opened or closed, wherein the exhaust rate of the exhaust bypass is smaller than the pumping rate of the vacuum pump.

The exhaust bypass can be a conduit with a small pipe diameter, and the conduit can be connected in parallel with the vacuum pump through an angle valve and communicated with the coating cavity 100. And when the precursor is injected into the reaction cavity, the vacuum pump is closed and the exhaust bypass is opened, so that only the tail gas is discharged through the guide pipe. However, the small diameter of the conduit will make the air intake rate in the reaction chamber larger than the air exhaust rate, thereby maintaining a higher pressure in the reaction chamber.

When the purge gas is filled into the reaction cavity, the vacuum pump can be opened, so that the air extraction efficiency is improved, and the cleaning efficiency of the precursor is improved. The vacuum pump is opened, and the exhaust bypass can be closed, so that the conduit with a thin pipe diameter is prevented from being blocked after long-time work. Compared with a butterfly valve, the exhaust bypass is arranged to achieve the mode that the air exhaust speed is adjustable, and the cost is lower.

Obviously, in other embodiments, an electric control device may be provided to adjust the power of the vacuum pump, so as to achieve the purpose of adjusting the pumping rate.

Referring to fig. 2 again, in the present embodiment, the inner cavity 110 includes a first straight pipe section 111, a second straight pipe section 112 and a tapered pipe section 113. The inner diameter of the first straight pipe section 111 is smaller than the inner diameter of the second straight pipe section 112, the first straight pipe section 111 and the second straight pipe section 112 are respectively communicated with the small end and the large end of the taper pipe section 113, the air inlet port and the air outlet port are respectively arranged on the first straight pipe section 111 and the second straight pipe section 112, and the powder to be coated can be contained in the first straight pipe section 111.

The first straight pipe section 111, the second straight pipe section 112 and the tapered pipe section 113 may be integrally formed, and are also connected by welding. At this time, the area of the overflowing end surface of the inner cavity 110 is gradually increased in the direction from the inlet port to the outlet port. Wherein the first straight tube section 111 with small diameter is used for placing the powder, thereby being capable of obtaining higher initial velocity of the powder when fluidizing.

The diameter of the conical section 113 is gradually increased, so that the gas flow rate into the conical section 113 is gradually decreased, and the pressure drop of the powder or the gas is gradually decreased. Therefore, sudden sedimentation of the powder due to the lifting can be prevented, thereby reducing the interaction between the powder particles. The second straight pipe section 112 of large diameter provides a buffer space for the powder particles to splash, thereby further preventing the gas outlet port from being blocked or a large amount of powder from being adsorbed on the filter screen of the gas outlet port.

It should be noted that, in other embodiments, the inner cavity 110 may also be a cavity structure formed by splicing a plurality of straight pipe sections with successively increasing or decreasing pipe diameters. In addition, the inner cavity 110 may also be a conical hollow structure, and the air inlet port is located at the small end, and the air outlet port is located at the large end. At this time, the area of the flow passage end surface of the inner cavity 110 continuously increases in the direction from the inlet port to the outlet port.

Further, in the present embodiment, the taper angle of the taper pipe section 113 is 30 to 85 degrees. Experiments prove that when the taper angle of the taper pipe section 113 is between 30 and 85 degrees, the powder is better in dispersion effect and less in probability of contacting the air outlet port.

The dimensions of the inner cavity 110 are generally as follows: the pipe diameter d of the first straight pipe section 111 is 20-100 mm, and the height h1 of the first straight pipe section 111 is 10-150 mm; the total height h3 of the inner cavity 110 is 50 to 800 mm; the height h2 of the cone segment 113 is 30 to 400 mm; the angle α, which is one-half the cone angle of the cone section 113, is 15 to 45 degrees.

At this size, when the total intake air flow rate is 100sccm to 50slm, the air flow velocity in the first tapered pipe section 111 is high, and the air flow velocity in the second straight pipe section 112 is sharply decreased according to the simulation of the air flow velocity distribution in the inner cavity 110 shown in fig. 3.

Referring to fig. 1 again, in the present embodiment, the coating chamber 100 further includes an outer chamber 120, the inner chamber 110 is accommodated in the outer chamber 120, and the gas outlet port is communicated with the outer chamber 120, and an exhaust port is formed at an end of the outer chamber 120 away from the gas outlet port.

The outer chamber 120 is generally cylindrical and is disposed coaxially with the inner chamber 110. The air exhaust mechanism 400 in this embodiment is communicated with the exhaust port, and directly exhausts air to the outer cavity 120, thereby exhausting air to the inner cavity 110. On one hand, the outer cavity 120 can protect and insulate the inner cavity 110; on the other hand, the air exhaust mechanism 400 is not directly connected to the air outlet port of the inner cavity 110, and the air outlet port is far away from the air outlet port. Therefore, the powder in the inner cavity 110 can be effectively prevented from being sucked into the suction mechanism 400.

In addition, a cavity door 121 is further disposed at one side end of the outer cavity 120, so that the inner cavity 110 can be conveniently put in and taken out.

In this embodiment, the coating chamber 100 further includes a vibration mechanism 130 for driving the inner chamber 110 to vibrate. The vibration mechanism 130 can assist in dispersing the powder particles by generating mechanical vibration, thereby reducing the powder adsorption of the inner wall of the cavity of the inner cavity 110 and the filter screen of the air outlet port, and further effectively improving the uniform deposition effect of the large amount of powder particles.

It should be noted that in other embodiments, the powder particles may be dispersed by stirring, rotating, or the like.

Further, in the present embodiment, the vibration mechanism 130 may drive the inner cavity 110 to vibrate relative to the outer cavity 120. The vibration mechanism 130 includes a vibration source 131, a link 132, and a bellows 133.

The vibration source 131 is used to generate vibration energy, and may be a vibration generating device such as a vibration motor, a pneumatic vibrator, or an ultrasonic vibration rod. The vibration source 131 is disposed outside the outer cavity 120, connected to the inner cavity 110 through a connecting rod 132, and transmits vibration energy generated by the vibration source 131 to the inner cavity 110. Specifically, the connecting rod 132 is inserted into the outer cavity 120, and two ends of the connecting rod are respectively fixedly connected to the outer wall of the inner cavity 110 and the vibration source 131. The connecting rod 132 is sleeved with the bellows 133, and two ends of the bellows 133 are respectively connected to the outer wall of the inner cavity 110 and the inner wall of the outer cavity 120 in a sealing manner. Thus, a sealed space is formed between the inner chamber 110, the outer chamber 120 and the bellows 133, thereby preventing the vacuum of the entire coating chamber 100 from being damaged due to the gap at the joint of the connecting rod 132 and the outer chamber 120.

The powder coating device 10 and the coating chamber 100 are filled with fluidizing gas from the gas inlet, so that the powder can obtain a high initial velocity and be fluidized. The area of the flow cross section of the inner cavity 110 tends to increase in the direction from the inlet port to the outlet port. According to the fluid equation, the gas flow rate in the direction from the inlet port to the outlet port will have a decreasing trend. When the flow rate drops to a certain extent, the lifted powder will gradually start to settle and be lifted again when approaching the inlet port. Thus, the powder will form an internal circulation within a limited height, thereby increasing the interaction between the powder particles and reducing agglomeration. Meanwhile, the powder can be prevented from touching and being adsorbed on the air outlet port due to the limited lifting height of the powder. Furthermore, the powder forming the internal circulation increases the impact on the chamber wall and also reduces the powder adsorbed on the chamber wall. Therefore, the uniformity of the coating film is remarkably improved.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only represent some embodiments of the present invention, and the description thereof is specific and detailed, but not to be construed as limiting the scope of the present invention. It should be noted that, for those skilled in the art, without departing from the spirit of the present invention, several variations and modifications can be made, which are within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.

Claims

1. The utility model provides a coating film cavity, includes interior cavity, its characterized in that, the axial both ends of interior cavity are formed with inlet port respectively and give vent to anger the port, and the powder of treating the coating film can be accommodated in interior cavity is close to inlet port's one end, and by inlet port arrives in the direction of the port of giving vent to anger, the cross sectional area that overflows of interior cavity is the increase trend.

2. The coating chamber according to claim 1, wherein the inner chamber comprises a first straight tube section, a second straight tube section and a tapered tube section, the first straight tube section has an inner diameter smaller than that of the second straight tube section, the first straight tube section and the second straight tube section are respectively communicated with the small end and the large end of the tapered tube section, the gas inlet port and the gas outlet port are respectively disposed on the first straight tube section and the second straight tube section, and the powder to be coated can be accommodated in the first straight tube section.

3. The coating chamber according to claim 2, wherein the height of the inner chamber is 50 mm to 800 mm, the diameter of the first straight tube is 20 mm to 100 mm, the height of the first straight tube is 10 mm to 150 mm, the height of the conical tube is 30 mm to 400 mm, and the half cone angle of the conical tube is 15 degrees to 45 degrees.

4. The coating chamber according to claim 1, further comprising an outer chamber, wherein the inner chamber is accommodated in the outer chamber, the air outlet port is communicated with the outer chamber, and an exhaust port is formed at an end of the outer chamber away from the air outlet port.

5. The coating chamber of claim 1, further comprising a vibration mechanism for driving the inner chamber to vibrate.

6. The coating chamber of claim 4, further comprising a vibration mechanism for driving the inner chamber to vibrate relative to the outer chamber, wherein the vibration mechanism comprises:

a vibration source;

the bellows is sleeved on the connecting rod, and two ends of the bellows are respectively connected with the outer wall of the inner cavity and the inner wall of the outer cavity in a sealing manner.

7. A powder coating device, comprising:

the coating chamber according to any one of claims 1 to 6;

8. The powder coating device of claim 7, further comprising an exhaust gas treatment mechanism disposed between the suction mechanism and the coating chamber.

9. The powder coating device of claim 7, wherein the air pumping mechanism is capable of adjusting the air pumping rate of the inner cavity.

10. The powder coating device of claim 9, wherein the gas-pumping mechanism comprises a vacuum pump and a butterfly valve disposed between the vacuum pump and the coating chamber.

11. The powder coating device according to claim 9, wherein the air suction mechanism comprises a vacuum pump, and an exhaust bypass which is connected in parallel with the vacuum pump and can be opened or closed, and the exhaust rate of the exhaust bypass is smaller than that of the vacuum pump.