Metal powder screening mechanism and powder feeding device

Abstract

The invention belongs to the technical field of metal powder screening, and discloses a metal powder screening mechanism and a powder feeding device. The metal powder screening mechanism comprises a box body, a first metal roller and an electrode tube, a first powder feeding cavity and a second powder feeding cavity are formed in the box body, the first metal roller is rotatably arranged in the box body and is grounded through a grounding wire, and the electrode tube is arranged in the box body and can form a corona electric field; the first metal roller rotates to enable the to-be-screened powder flowing out of the first powder feeding cavity to be charged and adsorbed to the first metal roller, the first metal roller rotates to enable the to-be-screened powder to leave the corona electric field, the metal powder is thrown into the second powder feeding cavity after releasing the charges, and impurities are still adsorbed to the first metal roller. According to the screening mechanism for the metal powder, the non-contact and automatic screening process is achieved through the physical principle, the screening efficiency and purity are improved, no damage is caused to the metal powder, and the stability of the subsequent sintering process and the quality of finished products are guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of metal powder screening, and in particular to a metal powder screening mechanism and a powder feeding device. Background Art

[0002] As a cutting-edge manufacturing technology, the uniqueness of directed energy deposition molding technology lies in its ability to break away from the constraints of traditional mold casting and forging, and directly realize the integrated molding of highly complex components, thus showing extraordinary technical potential and advantages in the field of precision manufacturing. The basic principle of this technology is to use the laser nozzle as an energy medium to accurately sinter the metal powder delivered by the powder feeding system at a specified position at high temperature to build the required three-dimensional structure.

[0003] Directed energy deposition molding technology has high requirements for the purity of metal powder. However, in the preparation of metal powder and its subsequent processing, it is difficult to completely avoid the mixing of non-metallic impurities, such as ceramic particles and organic matter, which seriously interfere with the stability of the sintering process and the quality of the finished product.

[0004] Therefore, it is necessary to provide a metal powder screening mechanism and a powder feeding device to solve the above problems. Summary of the invention

[0005] The purpose of the present invention is to provide a metal powder screening mechanism and a powder feeding device, which utilize physical principles to realize a contactless and automated screening process, improve the screening efficiency and purity, and do not damage the metal powder, thereby ensuring the stability of the subsequent sintering process.

[0006] To achieve this object, the present invention adopts the following technical solutions:

[0007] The metal powder screening mechanism is used to screen the metal powder and impurities in the powder to be screened, including:

[0008] A box body, wherein a first powder delivery chamber and a second powder delivery chamber are provided in the box body;

[0009] A first metal roller is rotatably disposed in the box, and the first metal roller is grounded through a grounding wire;

[0010] An electrode tube, the electrode tube is arranged in the box body, and the electrode tube can form a corona electric field so that the powder to be sieved flowing out of the first powder feeding chamber is charged and adsorbed on the first metal roller;

[0011] The first metal roller rotates to make the powder to be sieved leave the corona electric field, and the metal powder is thrown into the second powder feeding chamber after releasing the electric charge, and the impurities are still adsorbed on the first metal roller.

[0012] Preferably, the metal powder screening mechanism further comprises:

[0013] A conveying pipe is connected to the first powder feeding chamber, and the powder to be sieved is conveyed to the first powder feeding chamber by the conveying pipe.

[0014] Preferably, a first recovery chamber is further provided in the box body, and a first metal brush is arranged in the box body, and the first metal brush can brush the impurities on the first metal roller into the first recovery chamber.

[0015] Preferably, the metal powder screening mechanism further comprises:

[0016] A separation roller assembly is arranged in the housing with an adjustable speed, and the separation roller assembly has an electric field pointing to its axis so that the metal powder flowing out of the second powder feeding chamber is charged and adsorbed on the separation roller assembly; the separation roller assembly is configured to eject the metal powder of non-target particle size and retain the metal powder of target particle size when rotating at a set speed.

[0017] Preferably, the separation roller assembly comprises:

[0018] A second metal roller, whose rotation speed is adjustable and arranged in the box;

[0019] The annular electric field generator is arranged around the outer circumference of the second metal roller, and the annular electric field generator can generate an electric field pointing to the axis of the second metal roller, so that the metal powder flowing out of the second powder feeding chamber is charged.

[0020] Preferably, the metal powder screening mechanism further comprises:

[0021] A powder collecting bin is arranged on the peripheral side of the separation roller assembly;

[0022] The second metal brush is arranged in the box and can brush the metal powder of the target particle size on the separation roller assembly into the powder collecting bin.

[0023] Preferably, a second recovery chamber is further provided in the box body, and the metal powder of non-target particle size is thrown into the second recovery chamber.

[0024] Preferably, the metal powder screening mechanism further comprises:

[0025] The first recovery pipe, the first recovery chamber and the second recovery chamber are connected to form a total recovery chamber, the first recovery pipe is connected to the total recovery chamber, and the impurities and the metal powder of non-target particle size are discharged through the first recovery pipe.

[0026] Preferably, the metal powder screening mechanism further comprises:

[0027] a second recovery pipe, the second recovery pipe being in communication with the first recovery chamber, and the impurities being discharged through the second recovery pipe;

[0028] A third recovery pipe is connected to the second recovery chamber, and the metal powder of non-target particle size is discharged through the third recovery pipe.

[0029] The powder feeding device comprises:

[0030] nozzle;

[0031] The above-mentioned metal powder screening mechanism, the nozzle is connected to the metal powder screening mechanism, and the metal powder screened by the metal powder screening mechanism is sprayed out from the nozzle.

[0032] Beneficial effects of the present invention:

[0033] The metal powder screening mechanism includes a box body, a first metal roller and an electrode tube. The box body is provided with a first powder feeding chamber and a second powder feeding chamber. The first metal roller is rotatably arranged in the box body. The first metal roller is grounded through a grounding wire. The electrode tube is arranged in the box body. The electrode tube can form a corona electric field so that the powder to be screened flowing out of the first powder feeding chamber is charged and adsorbed on the first metal roller. The first metal roller rotates to make the powder to be screened leave the corona electric field. The metal powder releases the charge and is thrown into the second powder feeding chamber, and the impurities are still adsorbed on the first metal roller.

[0034] The powder to be screened can flow out of the first powder feeding chamber to the first metal roller, and the corona electric field generated by the electrode tube can give the powder to be screened an electric charge, so that the powder to be screened is adsorbed on the first metal roller. As the first metal roller rotates, the powder to be screened adsorbed thereon leaves the electric field area. The metal powder in the powder to be screened has good conductivity and can quickly release the charge through the grounding wire connected to the first metal roller. Then the metal powder is thrown out due to the centrifugal force and smoothly enters the second powder feeding chamber for collection. In contrast, the conductivity of impurities is poor and will not discharge quickly, so they will always be adsorbed on the surface of the first metal roller and will not be thrown out with the metal powder. This metal powder screening mechanism uses physical principles to realize a contactless and automated screening process, improves the screening efficiency and purity, and does not damage the metal powder, ensuring the stability of the subsequent sintering process and the quality of the finished product. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 is a schematic diagram of a powder feeding device provided by the present invention;

[0036] Figure 2 It is a particle size distribution diagram of nickel-based high-temperature alloy powder after screening using the metal powder screening mechanism provided by the present invention in a specific experiment;

[0037] Figure 3 It is a detailed table of particle size distribution of nickel-based high-temperature alloy powder after screening using the metal powder screening mechanism provided by the present invention in a specific experiment.

[0038] In the figure:

[0039] 1. Box body; 11. First powder delivery chamber; 12. Second powder delivery chamber; 13. First recovery chamber; 14. Powder collection bin; 15. Second recovery chamber;

[0040] 21. a first metal roller; 22. a second metal roller;

[0041] 3. Ground wire;

[0042] 4. Electrode tube;

[0043] 51. delivery pipe; 52. first recovery pipe;

[0044] 61. a first metal brush; 62. a second metal brush;

[0045] 7. Toroidal electric field generator;

[0046] 8. Nozzle. DETAILED DESCRIPTION

[0047] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0048] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0049] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0050] In the description of this embodiment, the terms "upper", "lower", "right", etc., directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0051] Directed energy deposition molding technology has high requirements for the purity of metal powder. However, in the preparation of metal powder and its subsequent processing, it is difficult to completely avoid the mixing of non-metallic impurities, such as ceramic particles and organic matter, which seriously interfere with the stability of the sintering process and the quality of the finished product.

[0052] In order to solve the above problems, Figure 1 As shown, this embodiment provides a metal powder screening mechanism for screening metal powder and impurities in powder to be screened, and the metal powder screening mechanism includes a box body 1, a first metal roller 21 and an electrode tube 4. A first powder feeding chamber 11 and a second powder feeding chamber 12 are provided in the box body 1. The first metal roller 21 is rotatably arranged in the box body 1. The first metal roller 21 is grounded through a grounding wire 3. The electrode tube 4 is arranged in the box body 1. The electrode tube 4 can form a corona electric field so that the powder to be screened flowing out of the first powder feeding chamber 11 is charged and adsorbed on the first metal roller 21. The first metal roller 21 rotates to make the powder to be screened leave the corona electric field, and the metal powder is thrown into the second powder feeding chamber 12 after releasing the charge, and the impurities are still adsorbed on the first metal roller 21.

[0053] The powder to be screened can flow out of the first powder feeding chamber 11 to the first metal roller 21, and the corona electric field generated by the electrode tube 4 can give the powder to be screened an electric charge, so that the powder to be screened is adsorbed on the first metal roller 21. As the first metal roller 21 rotates, the powder to be screened adsorbed thereon leaves the corona electric field area. The metal powder in the powder to be screened can quickly release the charge through the grounding wire 3 connected to the first metal roller 21 due to its good conductivity. Then the metal powder is thrown out due to the centrifugal force and smoothly enters the second powder feeding chamber 12 for collection. In contrast, the conductivity of impurities is poor and will not discharge quickly, so they will always be adsorbed on the surface of the first metal roller 21 and will not be thrown out with the metal powder. This metal powder screening mechanism uses physical principles to realize a contactless and automated screening process, improves the screening efficiency and purity, and does not damage the metal powder, ensuring the stability of the subsequent sintering process and the quality of the finished product.

[0054] Specifically, Figure 1 As shown, a first recovery chamber 13 is also provided in the box body 1, and a first metal brush 61 is provided in the box body 1, and the first metal brush 61 can brush the impurities on the first metal roller 21 into the first recovery chamber 13. The bristles of the first metal brush 61 are in contact with the surface of the first metal roller 21, and the impurities adsorbed on the first metal roller 21 are effectively stripped off through physical brushing, so that the impurities are recovered into the first recovery chamber 13. Cleaning the impurities on the first metal roller 21 can maintain the efficient operation of the screening mechanism of the metal powder, and prevent the long-term accumulated impurities from causing wear or corrosion to the first metal roller 21, thereby affecting the screening effect and equipment performance.

[0055] In the specific implementation process, the first metal roller 21 rotates counterclockwise, the outlet of the first powder feeding chamber 11, the inlet of the second powder feeding chamber 12 and the inlet of the first recovery chamber 13 are arranged in sequence according to the rotation direction of the first metal roller 21, and the first metal brush 61 is arranged at the same position as the inlet of the first recovery chamber 13. The powder to be screened flows out from the outlet of the first powder feeding chamber 11 and is adsorbed on the first metal roller 21. The first metal roller 21 rotates so that the metal powder with released charge is thrown out to the second powder feeding chamber 12. The impurities continue to rotate with the first metal roller 21 to the first metal brush 61, and fall into the first recovery chamber 13 under the brushing of the first metal brush 61.

[0056] In the directed energy deposition molding technology, the particle size of metal powder is also an important factor affecting the quality of molded parts. Since the laser energy input is constant, when the metal powder particle size distribution is uneven, that is, there is a significant difference, the metal powder with a larger particle size may not melt fully under the laser energy input, and then leave unfused defects in the molding process; the metal powder with a smaller particle size may overburn under the laser energy input, forming a keyhole defect. Therefore, accurately controlling the particle size distribution of metal powder and ensuring that it is uniform within a certain range is the key to improving the precision of directed energy deposition molding technology and the quality of finished products.

[0057] To solve the above problems, the metal powder screening mechanism also includes a separation roller assembly, which is arranged in the box body 1 with an adjustable speed. The separation roller assembly has an electric field pointing to its axis so that the metal powder flowing out of the second powder feeding chamber 12 is charged and adsorbed on the separation roller assembly. The separation roller assembly is configured to eject metal powder of non-target particle size and retain metal powder of target particle size when rotating at a set speed.

[0058] After the metal powder is adsorbed on the separation roller assembly, it is constantly subjected to its own gravity, electric field force, friction force and centrifugal force. Assuming that the rotation speed of the separation roller assembly can just keep the metal powder with a mass of m on the separation roller assembly, the force equation of the metal powder in the center direction is: mg·cosθ+F 电场 =mω 2 R, the mass of the metal powder is: Where r is the particle size of the metal powder, μ is the friction coefficient between the metal powder and the separation roller assembly, and R is the distance between the metal powder and the axis of the separation roller assembly. The angular velocity of the separation roller assembly is: It can be understood that at this time, metal powders with a particle size less than or equal to r can stay on the separation roller assembly under the action of the electric field force, while metal powders with a particle size greater than r will be thrown out under the action of the centrifugal force. The rotation speed of the separation roller assembly is set according to the target particle size, and metal powders larger than the target particle size will be thrown out, while metal powders with the target particle size will still stay on the separation roller assembly. This screening method is not only fast, but also can accurately control the particle size range and improve screening efficiency.

[0059] Specifically, the separation roller assembly includes a second metal roller 22 and a toroidal electric field generator 7. The second metal roller 22 is arranged in the housing 1 with an adjustable speed. The toroidal electric field generator 7 is arranged around the outer periphery of the second metal roller 22. The toroidal electric field generator 7 can generate an electric field pointing to the axis of the second metal roller 22, so that the metal powder flowing out of the second powder feeding chamber 12 is charged. That is, the charged metal powder is adsorbed on the second metal roller 22. The above R is the radius of the second metal roller 22. The speed of the second metal roller 22 is set according to the target particle size, and the metal powder of the target particle size can be screened out.

[0060] Furthermore, the metal powder screening mechanism also includes a powder collecting bin 14 and a second metal brush 62. The powder collecting bin 14 is arranged on the peripheral side of the separation roller assembly, and the second metal brush 62 is arranged in the box body and can brush the metal powder of the target particle size on the separation roller assembly into the powder collecting bin 14. Through the second metal brush 62, the metal powder of the target particle size adsorbed on the separation roller assembly can be brushed off and collected in the powder collecting bin 14, making it more convenient to subsequently process or transfer the metal powder of the target particle size.

[0061] Specifically, Figure 1 As shown, a second recovery chamber 15 is also provided in the box body 1, and metal powders of non-target particle sizes are thrown into the second recovery chamber 15. Metal powders of non-target particle sizes are effectively collected in the second recovery chamber 15, avoiding waste. These metal powders can be further processed or screened to meet the needs of other processes or production, thereby improving economic benefits.

[0062] Specifically, Figure 1 As shown, the screening mechanism of the metal powder further includes a conveying pipe 51, which is connected to the first powder feeding chamber 11, and the powder to be screened is transported to the first powder feeding chamber 11 by the conveying pipe 51. The continuous conveying capacity of the conveying pipe 51 ensures the continuity of the screening process. The metal powder can continuously enter the box 1 through the conveying pipe 51 for screening, reducing the production interruption caused by waiting for feeding, and further improving the production efficiency.

[0063] In an optional embodiment, if Figure 1 As shown, the screening mechanism for the metal powder also includes a first recovery pipe 52, the first recovery chamber 13 and the second recovery chamber 15 are connected to form a total recovery chamber, the first recovery pipe 52 is connected to the total recovery chamber, and impurities and metal powders of non-target particle sizes are discharged through the first recovery pipe 52. By connecting the first recovery chamber 13 and the second recovery chamber 15 to form a total recovery chamber, and then uniformly discharging impurities and metal powders of non-target particle sizes through the first recovery pipe 52, centralized recovery and processing of these materials is achieved. This not only simplifies the recovery process, but also improves the recovery efficiency.

[0064] In another optional embodiment, the screening mechanism of the metal powder also includes a second recovery pipe (not shown in the figure) and a third recovery pipe (not shown in the figure), the second recovery pipe is connected to the first recovery chamber 13, the third recovery pipe is connected to the second recovery chamber 15, impurities are discharged by the second recovery pipe, and metal powders of non-target particle size are discharged by the third recovery pipe. By discharging the impurities separately through the second recovery pipe, it is more convenient to carry out subsequent treatment, such as classification, recycling, disposal, etc.; although the metal powders of non-target particle size do not meet the current production requirements, they still have certain utilization value. Discharging them separately through the third recovery pipe can realize the reuse or further processing of these powders, avoiding the waste of resources.

[0065] like Figure 1 As shown, this embodiment also provides a powder feeding device, which includes the above-mentioned metal powder screening mechanism and nozzle 8, and the nozzle 8 is fixed to the box 1 and communicated with the powder collecting bin 14. The metal powder screening mechanism can ensure that only metal powder that meets the requirements enters the nozzle 8, and the nozzle 8 can stably and continuously feed powder, thereby improving production efficiency and stability.

[0066] Specifically, the powder feeding device also includes a driving component, which is configured to drive the housing 1 to move along the X-axis direction, the Y-axis direction or the Z-axis direction. The driving component can drive the housing 1 to move freely in three-dimensional space (X-axis, Y-axis, Z-axis), which enables the powder feeding device to flexibly adapt to different process requirements and achieve precise powder feeding. For the sake of simplicity, the specific structure of the driving component is not described in detail herein. Any structure in the prior art that can achieve three-way (X-axis, Y-axis, Z-axis) drive can be used as the driving component of this embodiment.

[0067] The following is a set of specific experiments to verify the screening effect of this metal powder screening mechanism:

[0068] The unscreened nickel-based high-temperature alloy powder is screened using a metal powder screening mechanism. There will be a large number of ceramic particles in the unscreened nickel-based high-temperature alloy powder, with a particle size between 1μm-250μm. The target particle size is 55μm. After calculation, the diameter of the first metal roller 21 is set to 200mm-300mm, the rotation speed of the first metal roller 21 is 200rpm / min-1000rpm / min, and the input voltage of the electrode tube 4 is 40000V-50000V; the diameter of the second metal roller 22 is 100mm-200mm, the rotation speed of the second metal roller 22 is 100rpm / min-200rpm / min, the voltage of the toroidal electric field generator 7 is 220V-360V, and the spacing between it and the outer periphery of the second metal roller 22 is 20mm-100mm.

[0069] The screened nickel-based high-temperature alloy powder was sampled and tested for particle size. The test results are as follows: Figure 2 , Figure 3 As shown, the particle size distribution of the metal powder after screening shows that its D90 is reduced to 55.14μm, that is, the powder with a particle size less than 55.14μm accounts for 90% of the sample, and the peak position is narrow, and most of the powder is concentrated in 16.92μm-54.57μm. After the sampled powder was washed with water and observed under a microscope, no obvious ceramic particles were found.

[0070] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A metal powder screening mechanism, used to screen metal powder and impurities in the powder to be screened, characterized in that: include: A box body (1), wherein a first powder delivery chamber (11) and a second powder delivery chamber (12) are provided in the box body (1); A first metal roller (21) is rotatably disposed in the box (1), and the first metal roller (21) is grounded via a grounding wire (3); an electrode tube (4), the electrode tube (4) being arranged in the box body (1), the electrode tube (4) being capable of forming a corona electric field so that the powder to be sieved flowing out of the first powder feeding chamber (11) is charged and adsorbed on the first metal roller (21); The first metal roller (21) rotates to allow the powder to be sieved to leave the corona electric field, and the metal powder is ejected into the second powder feeding chamber (12) after releasing the electric charge, while the impurities are still adsorbed on the first metal roller (21).

2. The metal powder screening mechanism according to claim 1, characterized in that: The metal powder screening mechanism also includes: A conveying pipe (51), wherein the conveying pipe (51) is in communication with the first powder feeding chamber (11), and the powder to be sieved is conveyed into the first powder feeding chamber (11) by the conveying pipe (51).

3. The metal powder screening mechanism according to claim 1, characterized in that: A first recovery chamber (13) is also provided in the box body (1), and a first metal brush (61) is arranged in the box body (1), and the first metal brush (61) can brush the impurities on the first metal roller (21) into the first recovery chamber (13).

4. The metal powder screening mechanism according to claim 3, characterized in that: The metal powder screening mechanism also includes: A separation roller assembly is arranged in the housing (1) with an adjustable speed, and the separation roller assembly has an electric field pointing to its axis, so that the metal powder flowing out of the second powder feeding chamber (12) is charged and adsorbed on the separation roller assembly; the separation roller assembly is configured to eject the metal powder of non-target particle size and retain the metal powder of target particle size when rotating at a set speed.

5. The metal powder screening mechanism according to claim 4, characterized in that: The separation roller assembly comprises: A second metal roller (22) is arranged in the box (1) with an adjustable rotation speed; An annular electric field generator (7) is arranged around the outer circumference of the second metal roller (22), and the annular electric field generator (7) is capable of generating an electric field pointing to the axis of the second metal roller (22), so that the metal powder flowing out of the second powder feeding chamber (12) is charged.

6. The metal powder screening mechanism according to claim 4, characterized in that: The metal powder screening mechanism also includes: A powder collecting bin (14) is arranged on the peripheral side of the separation roller assembly; A second metal brush (62) is disposed in the housing (1) and is capable of brushing the metal powder of a target particle size on the separation roller assembly into the powder collecting bin (14).

7. The metal powder screening mechanism according to claim 4, characterized in that: A second recovery chamber (15) is also provided in the box body (1), and the metal powder of non-target particle size is ejected into the second recovery chamber (15).

8. The metal powder screening mechanism according to claim 7, characterized in that: The metal powder screening mechanism also includes: A first recovery pipe (52), the first recovery chamber (13) and the second recovery chamber (15) are connected to form a total recovery chamber, the first recovery pipe (52) is connected to the total recovery chamber, and the impurities and the metal powder of non-target particle size are discharged through the first recovery pipe (52).

9. The metal powder screening mechanism according to claim 7, characterized in that: The metal powder screening mechanism also includes: a second recovery pipe, the second recovery pipe being in communication with the first recovery chamber (13), and the impurities being discharged through the second recovery pipe; A third recovery pipe is connected to the second recovery chamber (15), and the metal powder with a non-target particle size is discharged through the third recovery pipe.

10. A powder feeding device, characterized in that: include: Nozzle (8); According to the metal powder screening mechanism as described in any one of claims 1 to 9, the nozzle (8) is connected to the metal powder screening mechanism, and the metal powder screened by the metal powder screening mechanism is sprayed out from the nozzle.

Images