Active coating thickness controllable spraying device for preparing degradable active package

Abstract

The invention relates to the technical field of spraying devices, in particular to an active coating thickness-controllable spraying device for preparing degradable active packages, which comprises a coating box, the coating box is placed on the upper surface of a cart, spraying equipment is connected with the coating box, one end of a connecting pipe of the spraying equipment is connected with a shell, and a back cover diameter is mounted on the back surface of the shell through screws; the coating pressure control device has the beneficial effects that when a user needs to control the coating pressure, the user only needs to rotate the spray gun head, the spray gun head drives the second end cover, the second connecting ring at one end of the second end cover controls the first connecting ring and controls the first end cover again, and therefore the whole body rotates along with the spray gun head; the spray gun head drives the second end cover to move together, at the moment, the inner spiral spray pipe is driven to synchronously extend or contract through extension and compression of the elastic outer sleeve, the effective path length of the spiral spray pipe is changed, and due to the fact that the spiral spray pipe is made of materials, blockage of a spraying channel caused by pipe wall adhesion is avoided.

Description

Technical Field

[0001] This invention relates to the field of spraying equipment technology, specifically to a spraying device for controlling the thickness of an active coating prepared from biodegradable active packaging. Background Technology

[0002] The active coating thickness controllable spraying device is mainly used to apply active coatings to the surface of biodegradable packaging materials, enabling them to possess antibacterial, moisture-proof, and preservation functions in the food, pharmaceutical, and biomaterial packaging fields. With the rapid development of biodegradable packaging technology, the adhesion quality and thickness uniformity of the active coating have become key factors affecting product performance. Therefore, a spraying device capable of stably controlling coating thickness, adjusting spraying pressure, and ensuring unobstructed flow channels is urgently needed in the production process to meet the coating requirements of different materials and processes. The spraying device consists of a paint tank, a metering / transfer pump, a filter and delivery hose, a spray gun and corresponding nozzles, and a high-pressure pump. The paint is drawn from the paint tank by the metering or transfer pump, and after large particles are removed by the filter, it is pressurized to the spray gun end along the hose. At the spray gun, the high-pressure pump breaks the liquid into droplets to form a spray. The spray contacts the relatively moving workpiece surface and deposits to form a wet film, which is finally dried by the drying equipment. The pump's supply pressure, nozzle structure, and gas parameters jointly determine the atomized particle size and spray width, while the filter and hose ensure continuous and unobstructed delivery.

[0003] In the existing technology, active coating spraying equipment generally adopts a fixed flow channel structure and a non-adjustable spray gun. The spraying pressure mainly relies on the external pressure supply system for adjustment, which makes the coating thickness susceptible to factors such as material viscosity, clogging of the spray tank, and fluctuations in pipeline pressure. Summary of the Invention

[0004] The purpose of this invention is to provide a spraying device for preparing biodegradable active packaging with controllable active coating thickness, so as to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a paint box is included, which is placed on the upper surface of a trolley; a spraying device is connected to the paint box; one end of the connecting pipe of the spraying device is connected to a housing; a back cover is installed on the back of the housing by screws; a pressure ring is fixed on the surface of the back cover; a spray gun head is screwed to the end of the housing away from the back cover; and a spray pipe is connected to the other end of the connecting pipe through a connecting structure; the path of the spray pipe is controlled by a pressure control structure.

[0006] Preferably, the other end of the connecting pipe is located in the middle of the back cover, and one end of the nozzle is located in the middle of the back cover.

[0007] Preferably, the other end of the nozzle passes through the middle of the spray gun head, and the outer ring of the spray gun head is screwed onto the inner ring of the outer casing.

[0008] Preferably, the connection structure includes a first fixed cover, a second fixed cover, a sealing ring, a retaining ring, and a retaining groove. The first fixed cover is fixed to the other end of the connecting pipe and has a "U"-shaped cross-section. The second fixed cover is fixed to one end of the nozzle and has a "T"-shaped cross-section. The outer ring of the second fixed cover is fitted with a sealing ring. When the connecting pipe and the nozzle are connected, the outer ring of the sealing ring fits tightly with the inner ring of the first fixed cover. The retaining groove is opened in the inner ring of the first fixed cover and is a semi-circular annular groove. The retaining ring is fixed to the outer ring of the second fixed cover and has an annular structure. The retaining ring is inserted into the retaining groove and is located to the left of the sealing ring. The lowest end of the first fixed cover abuts against the highest end of the second fixed cover.

[0009] Preferably, the middle part of the nozzle has a spiral structure.

[0010] Preferably, the pressure control structure includes end cap one, elastic outer sleeve, and end cap two. End cap one has a slider fixed to its outer ring. The slider slides within a groove on the inner wall of the outer shell, with the left surface of the outer shell fitting against the top of the groove. End cap one is located on the back cover side inside the outer shell, and its cross-section is U-shaped. The nozzle passes through end cap one. End cap two is located inside the outer shell on the side away from the back cover. The left side of end cap two is fixed to the outer shell, and its cross-section is also U-shaped. The elastic outer sleeve connects end cap one and end cap two, which are connected by a positioning structure. The nozzle passes through end cap two and the elastic outer sleeve. The spiral tube in the middle of the nozzle is located inside the elastic outer sleeve. A through groove is provided inside the elastic outer sleeve, and this through groove is spiral-shaped, passing through both sides of the elastic outer sleeve. The spiral tube in the middle of the nozzle is fitted within this through groove.

[0011] Preferably, the positioning structure includes a first connecting ring and a second connecting ring. The first connecting ring is fixed to one end of the first end cap, and the second connecting ring is fixed to one end of the second end cap. The first connecting ring and the second connecting ring are located on the outside of the elastic outer sleeve, and one end of the first connecting ring slides inside the second connecting ring.

[0012] Compared with the prior art, the beneficial effects of the present invention are: The present invention proposes a spraying device for controlling the thickness of an active coating prepared from biodegradable active packaging. When the user needs to control the coating pressure, they only need to rotate the spray gun head. The spray gun head drives the end cap two, and the connecting ring two at one end of the end cap two controls the connecting ring one, which in turn controls the end cap one, causing the entire device to rotate. Due to the rotation of the spray gun head in or out, the spray gun head moves linearly, and the spray gun head drives the end cap two to move together. At this time, the elongation and compression of the elastic jacket drives the internal spiral nozzle to extend or contract synchronously, changing the effective path length of the spiral nozzle. The spiral nozzle itself... The special material ensures that it only undergoes axial expansion and contraction without lateral deformation, thus avoiding pipe wall adhesion that could block the spraying channel. As the spiral nozzle path lengthens, the pressure of the paint flowing through the nozzle is gradually absorbed and reduced by the longer spiral path, resulting in an automatic reduction in the thickness of the sprayed coating. Conversely, when the spiral nozzle path shortens, the pressure loss decreases, the spraying pressure increases, and the coating thickness increases accordingly. Furthermore, during rotation, the annular shape of the grooves and rings on the first and second fixed covers ensures that when the second fixed cover rotates synchronously with the nozzle, the first fixed cover and the connecting pipe will not rotate together. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the spray gun structure of the present invention; Figure 3 For the present invention Figure 2 Schematic diagram of the cross-sectional structure along the middle AA direction; Figure 4 For the present invention Figure 3 A magnified structural diagram at point A; Figure 5 This is a schematic diagram of the pressure control structure of the present invention; Figure 6 This is a schematic diagram of the positioning structure of the present invention.

[0014] In the diagram: 1. Trolley; 2. Paint tank; 3. Outer shell; 4. Connecting pipe; 5. Back cover; 6. Pressure ring; 7. End cap one; 8. Spray pipe; 9. Fixing cover one; 10. Fixing cover two; 11. Sealing ring; 12. Snap ring; 13. Snap groove; 14. Through groove; 15. Elastic outer sleeve; 16. Connecting ring one; 17. Connecting ring two; 18. End cap two; 19. Spray gun head. Detailed Implementation

[0015] To make the objectives, technical solutions, and advantages of the present invention clear and complete, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only some, not all, embodiments of the present invention, and are merely illustrative of the embodiments of the present invention. They are not intended to limit the embodiments of the present invention. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Example

[0016] Please see Figures 1 to 6 The present invention provides a technical solution: a spraying device for preparing a biodegradable active coating with controllable thickness, comprising a paint box 2, the paint box 2 being placed on the upper surface of a trolley 1, a spraying device connected to the paint box 2, a housing 3 being connected to one end of a connecting pipe 4 of the spraying device, a back cover 5 being installed on the back of the housing 3 by screws, the other end of the connecting pipe 4 being located in the middle of the back cover 5, one end of a spray pipe 8 being located in the middle of the back cover 5, a pressure ring 6 being fixed on the surface of the back cover 5, and a spray gun head 19 being screwed to the end of the housing 3 away from the back cover 5; Specifically, the spraying equipment consists of a paint tank, a metering / transfer pump, a filter and delivery hose, a spray gun and corresponding nozzles, and a high-pressure pump. The paint is drawn from the paint tank by the metering or transfer pump, and after large particles are removed by the filter, it is pressed to the spray gun end along the hose. At the spray gun, the high-pressure pump breaks the liquid into droplets to form a spray. The spray contacts the relatively moving workpiece surface and deposits to form a wet film. Finally, it is dried by the drying equipment. The pump supply pressure, nozzle structure, and gas parameters together determine the atomized particle size and spray width. The filter and hose ensure continuous and unblocked delivery. Example

[0017] Based on Embodiment 1, in order to achieve the connection between the connecting pipe 4 and the nozzle 8, and to prevent the connecting pipe 4 from rotating synchronously when the nozzle 8 is rotated, a connecting structure is proposed to connect the other end of the connecting pipe 4 to the nozzle 8. The other end of the nozzle 8 passes through the middle of the spray gun head 19, and the outer ring of the spray gun head 19 is screwed to the inner ring of the outer shell 3. The connecting structure includes a first fixing cover 9, a second fixing cover 10, a sealing ring 11, a retaining ring 12, and a retaining groove 13. The first fixing cover 9 is fixed to the other end of the connecting pipe 4, and the first fixing cover 9 has a "U" shaped cross-section. The second fixing cover 10... Fixed to one end of the nozzle 8, the second fixing cover 10 has a "convex" shaped cross section. The outer ring of the second fixing cover 10 is fitted with a sealing ring 11. When the connecting pipe 4 and the nozzle 8 are connected, the outer ring of the sealing ring 11 fits tightly with the inner ring of the first fixing cover 9. The slot 13 is opened in the inner ring of the first fixing cover 9. The slot 13 is a semi-circular annular groove. The retaining ring 12 is fixed to the outer ring of the second fixing cover 10. The retaining ring 12 has an annular structure and is stuck in the slot 13. The retaining ring 12 is located to the left of the sealing ring 11. The lowest end of the first fixing cover 9 presses against the highest end of the second fixing cover 10. Specifically, when the other end of the connecting pipe 4 is inserted into the middle of the back cover 5, and the fixing cap 9 at the end of the connecting pipe 4 is aligned with the outer ring of the fixing cap 10, the fixing cap 9 is then inserted into the outside of the fixing cap 10. At this time, the slot 13 opened in the inner ring of the fixing cap 9 is engaged by the retaining ring 12 fixed in the outer ring of the fixing cap 10. The inner ring of the fixing cap 9 is tightly fitted with the sealing ring 11, and the outer ring of the fixing cap 10 is also tightly fitted with the inner ring of the sealing ring 11. Thus, when the nozzle 8 is rotated, the connecting pipe 4 is prevented from rotating as well, so that the nozzle 8 can rotate freely while maintaining channel sealing and fluid continuity, thereby maintaining the stable state of the connecting pipe 4. Example

[0018] Based on Embodiment 2, in order to control the pressure of the paint sprayed from the spray gun head 19, a spiral structure is proposed for the middle part of the spray pipe 8. The path of the spray pipe 8 is controlled by a pressure control structure, which includes end cap 1 7, elastic sleeve 15, and end cap 2 18. A slider is fixed to the outer ring of end cap 1 7, and the slider slides in a groove opened in the inner wall of the outer shell 3. The left surface of the outer shell 3 is in contact with the top of the groove. End cap 1 7 is located on one side of the back cover 5 inside the outer shell 3. End cap 1 7 has a "U" shaped cross-section, and the spray pipe 8 passes through end cap 1 7. End cap 2 18 is located on the side of the outer shell 3 away from the back cover 5. The left side of end cap 2 18 is fixed to the outer shell 3. End cap 2 18 has a "U" shaped cross-section. The elastic sleeve 15 is connected to... It is connected between end cap 1 7 and end cap 2 18. End cap 1 7 and end cap 2 18 are connected by a positioning structure. The nozzle 8 passes through end cap 2 18 and elastic sleeve 15. The spiral tube in the middle of the nozzle 8 is located inside the elastic sleeve 15. The elastic sleeve 15 has a through groove 14. The through groove 14 is a spiral groove and passes through the left and right sides of the elastic sleeve 15. The spiral tube in the middle of the nozzle 8 is sleeved in the through groove 14. The positioning structure includes connecting ring 1 16 and connecting ring 2 17. Connecting ring 1 16 is fixed to one end of end cap 1 7 and connecting ring 2 17 is fixed to one end of end cap 2 18. Connecting ring 1 16 and connecting ring 2 17 are located outside the elastic sleeve 15. One end of connecting ring 16 slides inside connecting ring 2 17. Specifically, when the spray gun head 19 is screwed in or out, its linear displacement directly drives the connected end cap 18 to move back and forth accordingly. The end cap 18 then drives the connecting ring 16 through the connecting ring 17, causing the end cap 17 to synchronously generate the corresponding stroke with the entire pressure control structure. The elastic sleeve 15 deforms under the stretching or compression of the end cap 18, according to... Figure 3 It is known that, because the outer ring slider of end cap 7 is pressed against the top of the groove, end cap 7 will not move linearly with end cap 2 18. Furthermore, when the back cover 5 is closed, the pressure ring 6 on the surface of the back cover 5 presses against end cap 7, restricting its position and preventing it from shifting. End cap 7 can only rotate with end cap 2 18. Under the stretching or compression of end cap 2 18, the elastic outer sleeve 15 drives the spiral nozzle located in the through groove 14 to extend or retract along its spiral path. The nozzle 8, due to its... By combining a flexible material with a spiral structure, directional expansion and contraction can be achieved under the guidance of the elastic jacket 15. This allows the effective length of the spiral segment to change with the movement of the pressure control structure, thereby synchronously changing the flow resistance of the paint in the nozzle. When the effective path lengthens, greater energy loss occurs, reducing the spray pressure; when the path shortens, resistance decreases and the spray pressure increases. This allows for continuous and controllable adjustment of the coating thickness sprayed from the spray gun head 19, based on the overall movement of the pressure control structure. Furthermore, end cap 7 and end cap 18 are connected by a positioning structure, according to... Figure 6It can be seen that since the inner wall of the second connecting ring 17 restricts the rotation of the first connecting ring 16, when the second end cap 18 drives the second connecting ring 17 to rotate, the first connecting ring 16 will also rotate.

[0019] To reiterate, the elastic jacket 15 is made of highly elastic, fatigue-resistant thermoplastic polyurethane (TPU) or silicone rubber, which has good tensile and compressive properties, as well as corrosion and aging resistance; the nozzle 8 is made of highly flexible engineering-grade polyester or reinforced polytetrafluoroethylene (PTFE) material, which has both toughness and dimensional stability, and can generate axial expansion and contraction within the spiral path without lateral twisting or pipe wall adhesion, thereby ensuring smooth flow and stable pressure of the coating in the nozzle.

[0020] In use, the spray gun head 19 generates linear displacement by rotating in or out, first driving the connected end cap 18 to move back and forth. The end cap 18 then pulls the connecting ring 16 via the connecting ring 17, causing the entire pressure control structure to move accordingly. Simultaneously, because the outer ring slider of the end cap 7 presses against the top of the groove on the inner wall of the outer casing 3, and the pressure ring 6 on the surface of the back cover 5 presses the end cap 7 tightly after it is closed, the axial position of the end cap 7 is completely restricted, allowing it to rotate synchronously with the end cap 18 but preventing it from generating linear displacement. Under the movement of the end cap 18, the elastic outer sleeve 15 is stretched or compressed, and through its internal groove 14, it guides the spiral structure in the middle section of the spray nozzle 8, causing the spiral nozzle to undergo directional axial expansion and contraction, thereby changing the effective length of the internal spiral flow path and improving the flow of the coating. The resistance changes accordingly, ultimately achieving continuous adjustment of the spray pressure and coating thickness. To ensure rotational freedom during this pressure adjustment process, end cap 17 and end cap 28 are connected by a positioning structure, allowing connecting ring 16 to rotate together with end cap 28 under the limiting action of the inner wall of connecting ring 27, ensuring coordinated action of the pressure control structure. At the same time, the connecting pipe 4 and the spray pipe 8 are reliably decoupled through the snap-fit ​​method of fixed cap 19 and fixed cap 20. When fixed cap 19 is inserted into the outside of fixed cap 20, the slot 13 and the retaining ring 12 form an annular limit, and with the tight fit of the sealing ring 11 between the two, the spray pipe 8 will not drive the connecting pipe 4 to rotate during rotation, thus maintaining the free rotation of the spray pipe 8 and the sealing stability of the flow channel, ultimately achieving a stable and continuous spray control effect.

[0021] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A spraying device for controlling the thickness of an active coating prepared from biodegradable active packaging, comprising a coating tank (2), the coating tank (2) being placed on the upper surface of a trolley (1), a spraying device connected to the coating tank (2), and a housing (3) connected to one end of a connecting pipe (4) of the spraying device, characterized in that: The back cover (5) is installed on the back of the outer shell (3) by screws. A pressure ring (6) is fixed on the surface of the back cover (5). A spray gun head (19) is screwed to one end of the outer shell (3) away from the back cover (5). The other end of the connecting pipe (4) is connected to the spray pipe (8) through a connecting structure. The path of the spray pipe (8) is controlled by a pressure control structure.

2. The spraying device for controlling the thickness of the active coating in the preparation of biodegradable active packaging according to claim 1, characterized in that: The other end of the connecting pipe (4) is located in the middle of the back cover (5), and one end of the nozzle (8) is located in the middle of the back cover (5).

3. The spraying device for controlling the thickness of the active coating in the preparation of biodegradable active packaging according to claim 1, characterized in that: The other end of the nozzle (8) passes through the middle of the spray gun head (19), and the outer ring of the spray gun head (19) is screwed to the inner ring of the outer shell (3).

4. The spraying device for controlling the thickness of the active coating in the preparation of biodegradable active packaging according to claim 1, characterized in that: The connecting structure includes a first fixing cover (9), a second fixing cover (10), a sealing ring (11), a retaining ring (12), and a retaining groove (13). The first fixing cover (9) is fixed to the other end of the connecting pipe (4). The first fixing cover (9) has a "U" shaped cross-section. The second fixing cover (10) is fixed to one end of the nozzle (8). The second fixing cover (10) has a "U" shaped cross-section. The outer ring of the second fixing cover (10) is fitted with a sealing ring (11). The connecting pipe (4) and the nozzle (8) are connected. When connected, the outer ring of the sealing ring (11) fits tightly against the inner ring of the first fixed cover (9). The slot (13) is opened on the inner ring of the first fixed cover (9). The slot (13) is a semi-circular annular groove. The retaining ring (12) is fixed on the outer ring of the second fixed cover (10). The retaining ring (12) is an annular structure. The retaining ring (12) is stuck in the slot (13). The retaining ring (12) is located on the left side of the sealing ring (11). The lowest end of the first fixed cover (9) presses against the highest end of the second fixed cover (10).

5. The spraying device for controlling the thickness of the active coating in the preparation of biodegradable active packaging according to claim 1, characterized in that: The nozzle (8) has a spiral structure in the middle.

6. The spraying device for controlling the thickness of the active coating in the preparation of biodegradable active packaging according to claim 5, characterized in that: The pressure control structure includes end cap one (7), elastic outer sleeve (15), and end cap two (18). The outer ring of end cap one (7) is fixed with a slider, which slides in a groove opened in the inner wall of the outer shell (3), and the left surface of the outer shell (3) is in contact with the top of the groove. End cap one (7) is located on the side of the back cover (5) inside the outer shell (3). End cap one (7) has a "U" shaped cross-section, and the nozzle (8) passes through end cap one (7). End cap two (18) is located on the side of the outer shell (3) away from the back cover (5). The left side of end cap two (18) is fixed to the outer shell (3). The cross-section has a concave shape. The elastic sleeve (15) is connected between the first end cap (7) and the second end cap (18). The first end cap (7) and the second end cap (18) are connected by a positioning structure. The nozzle (8) passes through the second end cap (18) and the elastic sleeve (15). The spiral tube in the middle of the nozzle (8) is located inside the elastic sleeve (15). The elastic sleeve (15) has a through groove (14) inside. The through groove (14) is a spiral groove and passes through the left and right sides of the elastic sleeve (15). The spiral tube in the middle of the nozzle (8) is sleeved in the through groove (14).

7. The spraying device for controlling the thickness of the active coating in the preparation of biodegradable active packaging according to claim 6, characterized in that: The positioning structure includes a first connecting ring (16) and a second connecting ring (17). The first connecting ring (16) is fixed to one end of the first end cap (7), and the second connecting ring (17) is fixed to one end of the second end cap (18). The first connecting ring (16) and the second connecting ring (17) are located outside the elastic outer sleeve (15), and one end of the first connecting ring (16) slides inside the second connecting ring (17).

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