A continuous powder coating device

Abstract

The application belongs to the technical field of powder surface modification and physical vapor deposition, and particularly relates to a continuous feeding powder coating device, which comprises a frame body with a vacuum chamber arranged inside; a material conveying plate arranged in the vacuum chamber in an inclined manner, an internal feeding hopper arranged above the uppermost end of the material conveying plate, and an internal discharging hopper arranged at the lowermost end of the material conveying plate; an ultrasonic transducer arranged at the lower end of the material conveying plate; a target material arranged above the material conveying plate in a spaced manner; a screw conveying assembly, with a feeding end of the screw conveying assembly connected to a discharging end of the internal discharging hopper, and a discharging end of the screw conveying assembly connected to the internal feeding hopper; a feeding device, with a discharging end of the feeding device arranged in the internal feeding hopper; and a discharging device arranged at the lower end of the frame body. The problems of powder static residence, non-uniform coating, powder agglomeration and inability to continuously feed and discharge in the existing powder magnetron sputtering coating equipment are solved.

Description

Technical Field

[0001] This invention belongs to the field of powder surface modification and physical vapor deposition technology, specifically relating to a continuous feeding powder coating device. Background Technology

[0002] Powder coating technology has wide applications in electronic materials, composite materials, and hard coatings. Magnetron sputtering technology has become an important means of powder surface modification due to its advantages such as high sputtering efficiency, low substrate temperature rise, good film-substrate adhesion, and stable device performance.

[0003] However, existing powder magnetron sputtering coating equipment generally adopts a static tray-type processing mode, in which the powder is placed statically on the tray for sputtering. This processing mode has the following problems: the powder remains statically, resulting in uneven sputtering coverage and the existence of "dead zones"; dynamic powder renewal cannot be achieved, leading to low coating efficiency; the powder is prone to agglomeration, affecting coating uniformity; and continuous feeding and discharging cannot be achieved, resulting in low production efficiency.

[0004] For example, Chinese patent CN201511007623—a method for manufacturing an ultrafine powder magnetron sputtering coating device—discloses an ultrafine powder magnetron sputtering coating device that employs a multi-layer vibratory disk structure and a rotating cylindrical target collaborative system. The powder undergoes diffusion motion on the vibratory disk under centrifugal force, while the rotating cylindrical target achieves rotational sputtering of the target material. An ultrasonic transducer is positioned below the vibratory disk to prevent powder agglomeration. This scheme achieves the dispersion of powder in a plane, but the powder's trajectory is still limited by the planar structure of the vibratory disk, preventing the powder from fully tumbling and achieving all-around coating in three-dimensional space.

[0005] Chinese patent CN202511245116—"Toothed Magnetron Sputtering Device, Solid Particle Coating System and Coating Method"—discloses a solid particle coating system based on a toothed rotor. This system uses the meshing rotation of the toothed rotor to drive particle movement, and combines it with an ejector to draw solid particles into a circulation pipeline, achieving continuous transport and coating of particles within the pipeline. While this solution achieves continuous particle circulation through mechanical transmission, the particles move in a single direction during circulation, primarily along the pipeline axis, lacking a mechanism for powder tumbling and thorough mixing.

[0006] In summary, existing powder magnetron sputtering coating equipment has the following common problems: (1) Static residence of powder: The powder remains stationary in the tray, resulting in a sputtering "dead zone" that cannot be fully coated; (2) Uneven coating: Static placement causes different degrees of sputtering on different surfaces of the powder, resulting in uneven film thickness distribution; (3) Powder agglomeration: Powder is prone to re-agglomeration in a static state, which affects the dispersion effect; (4) Inability to continuously feed and discharge materials: It requires stopping the machine, breaking the vacuum, taking out materials, and adding materials, which seriously affects production efficiency. Summary of the Invention

[0007] The purpose of this invention is to provide a continuous feeding powder coating device to solve the problems of static powder retention, uneven coating, powder agglomeration, and inability to continuously feed and discharge powder in existing powder magnetron sputtering coating equipment.

[0008] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: A continuous feeding powder coating apparatus, comprising: The frame contains a vacuum chamber. The material conveying plate is inclined and installed in the vacuum chamber. The uppermost part of the material conveying plate is provided with an internal feed hopper, and the lowermost part is provided with an internal discharge hopper. An ultrasonic transducer is installed at the lower end of the material conveying plate; Target materials are spaced apart above the material conveying plate; A screw conveyor assembly, wherein the feed end of the screw conveyor assembly is connected to the discharge end of the internal discharge hopper, and the discharge end of the screw conveyor assembly is connected to the internal feed hopper; A feeding device is provided at the upper end of the frame, and the discharge end of the feeding device is provided in the internal feeding hopper; The discharge device is located at the lower end of the frame, and its feed end is connected to the discharge end of the internal discharge hopper.

[0009] A further technical solution is that the upper end of the material conveying plate is recessed to form a conveying groove. The material conveying plate is provided in at least two pieces and is arranged vertically at intervals. The conveying start end of the material conveying plate located above the upper material conveying plate is located below the inner feed hopper or below the conveying end of the material conveying plate above it. The conveying end of the material conveying plate located above the conveying start end of the material conveying plate located below it is located above the conveying start end of the material conveying plate located below it or points towards the inner discharge hopper.

[0010] A further technical solution is that each of the four corners at the lower end of the material conveying plate is equipped with an ultrasonic transducer.

[0011] A further technical solution is that the spiral conveying assembly includes a first pipe, a second pipe, and a third pipe connected in sequence. The inlet end of the first pipe is connected to the internal discharge hopper, and the discharge end of the third pipe is located above the internal feed hopper. The first pipe, the second pipe, and the third pipe are all equipped with a rotating shaft and a spiral pushing blade mounted on the rotating shaft. A motor for driving the rotating shaft to rotate is provided on the outside of the frame.

[0012] A further technical solution is that the feeding device includes an external feeding hopper, a feeding buffer chamber, and a feeding pipe arranged sequentially from top to bottom. A feeding valve is provided between the external feeding hopper and the feeding buffer chamber. A feeding pneumatic butterfly valve is provided on the feeding pipe. The lower end of the feeding pipe passes through the frame and is connected to the internal discharge hopper.

[0013] A further technical solution is that the discharge device includes a discharge pipe, a discharge buffer chamber and an external collection hopper arranged sequentially from top to bottom. The upper end of the discharge pipe is connected to the internal discharge hopper, and a discharge pneumatic butterfly valve is also provided between the discharge buffer chamber and the external collection hopper.

[0014] A further technical solution is that both the feeding buffer chamber and the discharging buffer chamber are equipped with a vacuum gauge interface, an independent air extraction port, and an air filling valve.

[0015] A further technical solution is that the discharge pneumatic butterfly valve and the feed pneumatic butterfly valve are interlocked.

[0016] A further technical solution is that an electrical control box is provided on one side of the frame, the electrical control box has a built-in controller, the controller has a built-in valve control module and an automatic feeding module, and an internal circulation counter and film thickness detection module are provided inside the frame.

[0017] Compared with the prior art, the present invention has at least one of the following beneficial effects: (1) Achieve full coverage sputtering: The powder is dynamically conveyed on the inclined plate and its position is constantly updated, eliminating the sputtering "dead zone" and achieving a coverage rate of nearly 100%; (2) High coating uniformity: Ultrasonic vibration causes the powder to "tumble" continuously, and each surface is uniformly sputtered, resulting in good film thickness distribution. (3) Preventing powder agglomeration: The continuous action of ultrasonic vibration on the powder effectively inhibits agglomeration. (4) Continuous feeding and discharging: The external feeding and circulation system enables continuous feeding and discharging without breaking the vacuum, eliminating the need for machine shutdown, vacuum breaking, material removal, and feeding. (5) Significantly improve production efficiency: Internal powder circulation sputtering + external continuous feeding and discharging increases daily production capacity by 10-20 times; (6) High equipment integration: compact structure, improved on the basis of existing magnetron sputtering equipment. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of a continuous feeding powder coating device according to the present invention.

[0019] Figure 2 This is a schematic diagram of the material conveying plate in this invention.

[0020] Figure 3 This is a schematic diagram of target sputtering in this invention.

[0021] Figure 4 This is a schematic diagram of powder rolling in this invention. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Example

[0023] Figure 1-4 This invention illustrates a preferred embodiment of a continuous feeding powder coating apparatus. In this embodiment, the continuous feeding powder coating apparatus specifically includes a frame 1, which has a vacuum chamber inside. The material conveying plate 2 is inclined and installed in the vacuum chamber. The uppermost part of the material conveying plate 2 is provided with an internal feed hopper 3, and the lowermost part is provided with an internal discharge hopper 4. An ultrasonic transducer 5 is disposed at the lower end of the material conveying plate 2; Target material 6 is spaced apart above the material conveying plate 2; A screw conveyor assembly, wherein the feed end of the screw conveyor assembly is connected to the discharge end of the internal discharge hopper 4, and its discharge end is connected to the internal feed hopper 3; A feeding device is provided at the upper end of the frame 1, and the discharge end of the feeding device is provided in the internal feeding hopper 3; The discharge device is located at the lower end of the frame 1, and its feed end is connected to the discharge end of the internal discharge hopper 4.

[0024] In this invention, the frame 1 is made of stainless steel, and the vacuum chamber inside it is 1200mm long × 600mm wide × 800mm high.

[0025] In this invention, the material conveying plate 2 is 800mm × 200mm × 5mm, made of stainless steel, and has an inclination angle of 8°. Figure 1 As shown, the powder slides from top to bottom, and an ultrasonic transducer 5 is arranged at each of the four corners below the material conveying plate 2.

[0026] In this invention, the target material 6 is a sputtering target material 6, specifically a tungsten target with a diameter of 150 mm.

[0027] In this invention, the ultrasonic transducer 5 has a rated power of 100W / unit and a frequency of 40kHz, and is arranged in a rectangular array at the four corners of the bottom surface of the material conveying plate 2.

[0028] The upper end of the material conveying plate 2 is recessed to form a conveying groove. There are at least two material conveying plates 2 arranged vertically at intervals. The conveying start end of the upper material conveying plate 2 is located below the inner feed hopper 3 or below the conveying end of the material conveying plate 2 above it. The conveying end of the upper material conveying plate 2 is located above the conveying start end of the lower material conveying plate 2. The conveying end of the lower material conveying plate 2 is located above the conveying start end of the material conveying plate 2 below it or points towards the inner discharge hopper 4.

[0029] In this embodiment, there are two material conveyor plates 2, as shown in the reference. Figure 1 As shown, the conveying start end of the upper material conveying plate 2 is located below the inner feed hopper 3, and the conveying end end of the upper material conveying plate 2 is located above the conveying start end of the lower material conveying plate 2. The conveying end end of the lower material conveying plate 2 points towards the inner discharge hopper 4.

[0030] Each of the four corners at the bottom of the material conveying plate 2 is provided with an ultrasonic transducer 5, which is arranged in a rectangular array at the four corners of the bottom surface of the material conveying plate 2.

[0031] The spiral conveyor assembly includes a first pipe 7, a second pipe 8, and a third pipe 9 connected in sequence. The inlet end of the first pipe 7 is connected to the internal discharge hopper 4, and the discharge end of the third pipe 9 is located above the internal feed hopper 3. Each of the first pipe 7, the second pipe 8, and the third pipe 9 is equipped with a rotating shaft 10 and a spiral pusher blade 11 mounted on the rotating shaft 10. A motor for driving the rotating shaft 10 to rotate is provided on the outside of the frame 1. The three motors are not shown in the attached figure, but are used to drive the three rotating shafts 10 to rotate. During the rotation of the rotating shaft 10, the spiral pusher blade 11 transfers the processed material from the internal discharge hopper 4 to the internal feed hopper 3, so that the material is continuously circulated and processed.

[0032] The feeding device includes an external feeding hopper 12, a feeding buffer chamber 13, and a feeding pipe 14 arranged sequentially from top to bottom. A feeding valve is provided between the external feeding hopper 12 and the feeding buffer chamber 13. A feeding pneumatic butterfly valve 15 is provided on the feeding pipe 14. The lower end of the feeding pipe 14 passes through the frame 1 and is connected to the internal discharge hopper 4.

[0033] The discharge device includes a discharge pipe 16, a discharge buffer chamber 17 and an external collection hopper 18 connected in sequence from top to bottom. The upper end of the discharge pipe 16 is connected to the internal discharge hopper 4. A discharge pneumatic butterfly valve 19 is also provided between the discharge buffer chamber 17 and the external collection hopper 18.

[0034] Both the feed buffer chamber 13 and the discharge buffer chamber 17 are equipped with a vacuum gauge interface 20, an independent air extraction port 21, and an air filling valve 22.

[0035] The discharge pneumatic butterfly valve 19 and the feed pneumatic butterfly valve 15 are interlocked to ensure that only one valve is open or both are closed at any given time. Simultaneously, a brief "lock" state is required when switching valves to ensure pressure balance.

[0036] An electrical control box 23 is provided on one side of the frame 1. The electrical control box 23 has a built-in controller, which includes a valve control module and an automatic feeding module. The frame 1 also has an internal circulation counter and a film thickness detection module. The controller is used to control all electrical components in this invention to operate. The internal circulation counter is used to record the number of times the powder passes through the sputtering zone in the internal circulation system, and is specifically set inside the third pipe 9.

[0037] The film thickness monitoring module, mounted on the material conveying plate 2, estimates the film thickness based on sputtering time and power. Once the target thickness is reached, an external circulation is triggered. The external circulation is also triggered when the number of cycles recorded by the internal circulation system reaches a set value.

[0038] Valve control module: controls the opening and closing sequence of the feed valve and discharge valve.

[0039] Automatic feeding module: After the internal loop reaches the set number of times, it automatically executes the discharge → feed process.

[0040] The workflow of this invention is as follows: Step 1: Initial loading: Open the pneumatic butterfly valve 15 and load 1 kg of diamond powder into the feed hopper 3 inside the top of the material conveying plate 2; Close the feed pneumatic butterfly valve 15 and start the vacuum system to evacuate to 3.0×10⁻³Pa; Fill with argon gas to a working pressure of 0.35 Pa; Step 2: Internal circulation sputtering; Activate the ultrasonic transducer 5 in group pulse mode; the vibration promotes the dispersion and downward movement of powder on the material conveying plate 2. The powder slides down from the upper right to the left of the material conveying plate 2 at the top. The powder falls onto the lower material conveyor plate 2 and slides down from the upper left to the right. Sputtering target 6 sputters and coats the falling powder; The powder falls from the material conveying plate 2 into the internal discharge hopper 4; The screw conveyor assembly lifts the powder to the top; The powder re-enters the upper material conveying plate 2, forming an internal circulation; The inner loop counter records the number of times the area is traversed by the splash zone; Step 3: Control the number of internal loop iterations; Set the number of internal circulation cycles based on the target film thickness; Single-layer coating ~100nm: 10 internal cycles; Double-layer coating ~200nm: target material can be replaced after 20 internal cycles; Multilayer composite membrane: internal circulation more than 30 times; Step 4: External material discharge without breaking the vacuum; Once the internal loop reaches the set number of iterations, the external discharge process is triggered. When the discharge pneumatic butterfly valve 19 is opened, the discharge buffer chamber 17 is connected to the vacuum chamber. The powder enters the discharge buffer chamber 17 from the internal circulation system; The discharge pneumatic butterfly valve 19 is closed, isolating the vacuum chamber; The discharge buffer chamber 17 is pressurized to atmospheric pressure; The bottom valve of the discharge buffer chamber 17 is opened, and the powder enters the external collection hopper 18; Step 5: External feeding; The external feeding hopper 12 adds new powder to the feeding buffer chamber 13; Close the inlet of feed buffer chamber 13 and start the molecular pump of feed buffer chamber 13 to evacuate to 10⁻²Pa; When the feed pneumatic butterfly valve 15 is opened, the feed buffer chamber 13 is connected to the vacuum chamber. New powder enters the internal circulation system; The feed pneumatic butterfly valve 15 is closed, restoring the vacuum chamber to its vacuum state; Step Six: The next cycle begins; Repeat steps two through five to achieve continuous production; Result evaluation: Characterization of the coated diamond powder: Sputter coverage: ≥98% eliminates "dead zones"; Film thickness uniformity: standard deviation <5%; Membrane coverage: ≥95%; Production efficiency: After 8 hours of continuous operation, the daily production capacity can reach 8kg; Vacuum stability: Vacuum fluctuation during internal circulation is <5%; fluctuation during external feeding circulation is <10%.

[0041] Although the invention has been described herein with reference to several illustrative embodiments, it should be understood that many other modifications and implementations can be devised by those skilled in the art, which will fall within the scope and spirit of the principles disclosed herein. More specifically, various variations and modifications can be made to the components and / or layout of the subject matter arrangement within the scope of the disclosure, drawings, and claims. Besides variations and modifications to the components and / or layout, other uses will be apparent to those skilled in the art.

Claims

1. A continuous feeding powder coating apparatus, characterized in that, include: A frame (1) is provided with a vacuum chamber inside; a material conveying plate (2) is inclinedly arranged inside the vacuum chamber, with an internal feed hopper (3) at the top and an internal discharge hopper (4) at the bottom; an ultrasonic transducer (5) is arranged at the bottom of the material conveying plate (2); a target material (6) is arranged at intervals above the material conveying plate (2); a spiral conveying assembly, the feed end of which is connected to the discharge end of the internal discharge hopper (4), and the discharge end of which is connected to the internal feed hopper (3); a feeding device is arranged at the top of the frame (1), and the discharge end of which is arranged inside the internal feed hopper (3); a discharge device is arranged at the bottom of the frame (1), and its feed end is connected to the discharge end of the internal discharge hopper (4).

2. The continuous feeding powder coating apparatus according to claim 1, characterized in that: The upper end of the material conveying plate (2) is recessed to form a conveying groove. The material conveying plate (2) is provided in at least two and is arranged vertically and horizontally. The conveying start end of the upper material conveying plate (2) is located below the inner feed hopper (3) or below the conveying end of the material conveying plate (2) above it. The conveying end of the upper material conveying plate (2) is located above the conveying start end of the lower material conveying plate (2). The conveying end of the lower material conveying plate (2) is located above the conveying start end of the lower material conveying plate (2) or points towards the inner discharge hopper (4).

3. The continuous feeding powder coating apparatus according to claim 1, characterized in that: Each of the four corners at the lower end of the material conveying plate (2) is equipped with an ultrasonic transducer (5).

4. The continuous feeding powder coating apparatus according to claim 1, characterized in that: The spiral conveying assembly includes a first pipe (7), a second pipe (8), and a third pipe (9) connected in sequence. The inlet end of the first pipe (7) is connected to the internal discharge hopper (4), and the discharge end of the third pipe (9) is located above the internal feed hopper (3). The first pipe (7), the second pipe (8), and the third pipe (9) are all provided with a rotating shaft (10) and a spiral pusher blade (11) on the rotating shaft (10). The frame (1) is provided with a motor on the outside for driving the rotating shaft (10) to rotate.

5. The continuous feeding powder coating apparatus according to claim 1, characterized in that: The feeding device includes an external feeding hopper (12), a feeding buffer chamber (13) and a feeding pipe (14) arranged sequentially from top to bottom. A feeding valve is provided between the external feeding hopper (12) and the feeding buffer chamber (13). A feeding pneumatic butterfly valve (15) is provided on the feeding pipe (14). The lower end of the feeding pipe (14) passes through the frame (1) and is connected to the internal discharge hopper (4).

6. The continuous feeding powder coating apparatus according to claim 5, characterized in that: The discharge device includes a discharge pipe (16), a discharge buffer chamber (17) and an external collection hopper (18) arranged sequentially from top to bottom. The upper end of the discharge pipe (16) is connected to the internal discharge hopper (4). A discharge pneumatic butterfly valve (19) is also provided between the discharge buffer chamber (17) and the external collection hopper (18).

7. The continuous feeding powder coating apparatus according to claim 6, characterized in that: Both the feed buffer chamber (13) and the discharge buffer chamber (17) are equipped with a vacuum gauge interface (20), an independent air extraction port (21), and an air filling valve (22).

8. The continuous feeding powder coating apparatus according to claim 7, characterized in that: The discharge pneumatic butterfly valve (19) and the feed pneumatic butterfly valve (15) are interlocked.

9. A continuous feeding powder coating apparatus according to any one of claims 1-8, characterized in that: An electrical control box (23) is provided on one side of the frame (1). The electrical control box (23) has a built-in controller. The controller has a built-in valve control module and an automatic feeding module. An internal circulation counter and a film thickness detection module are provided inside the frame (1).

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