Noise reduction air knife

Abstract

A noise reduction air knife comprises a shell, a noise reduction structure used for conducting noise reduction on airflow is arranged in the shell, the noise reduction structure is sequentially provided with a plurality of sets of noise reduction holes with the hole diameters decreasing in a gradient mode in the airflow direction, and the hole diameters of all the sets of noise reduction holes are equal. The bottom of the shell is provided with an air nozzle used for blowing out airflow, and the air nozzle is internally provided with sound-absorbing cotton and a sound-absorbing plate matched with the sound-absorbing cotton. Compared with the prior art, the noise reduction structure is arranged in the shell and used for conducting noise reduction on airflow, the multiple sets of noise reduction holes with the hole diameters decreasing in the gradient mode in the airflow direction are formed in the noise reduction structure, the hole diameters in the sets of noise reduction holes are the same, and gradual adjustment of the airflow speed is achieved through the multiple sets of noise reduction holes decreasing in the gradient mode; the pore diameter of each stage is reduced to generate a Venturi effect, so that the turbulence noise is reduced, the airflow kinetic energy is maintained, and the contradiction between noise reduction and wind pressure maintenance is solved; meanwhile, through the multiple sets of noise reduction holes, the uniformity and adaptability of airflow distribution are remarkably improved when airflow flows through the multiple noise reduction holes.

Description

Technical Field

[0001] This utility model relates to the field of air knife technology, specifically to a noise-reducing air knife. Background Technology

[0002] An air knife, also known as a pneumatic knife, is a device specifically designed to generate a powerful, high-speed airflow. It is primarily used for applications such as dehydration, dust removal, and cooling. Driven by a motor, the air knife draws in air, which is then forced through specially designed blades or nozzles to create a high-speed rotating airflow. Due to centrifugal force, this high-speed rotating airflow forms a powerful jet. This jet passes through a special flow channel or nozzle outlet, creating a high-speed airflow shear boundary at the exit. When this boundary comes into contact with the object being treated, it generates a strong shearing force, thereby achieving the effect of cutting, removing, or separating.

[0003] Currently, in manufacturing, semiconductor processing, and cleaning equipment fields, air knives are commonly used to achieve purging, drying, or cooling through high-speed airflow. However, traditional designs, due to airflow turbulence, eddies, and structural simplicity, are prone to generating significant noise, which not only affects the working environment but may also harm the health of operators. Furthermore, uneven airflow distribution reduces purging efficiency, leading to energy waste and fluctuations in process quality. Existing technologies attempt to mitigate noise by optimizing the internal airflow path of the air knife, but this often comes at the cost of sacrificing air pressure or uniformity.

[0004] Chinese Patent Application No. 202320587878.4 discloses a high-precision, low-noise air knife assembly. The disclosed low-noise air knife assembly includes an air knife body, which has a hollow structure and includes a first side and a second side arranged opposite to each other, as well as two end faces respectively arranged at both ends of the first side and the second side. At least one end face has an air inlet channel that connects to the air supply inside the air knife body to enter the air knife body. The lower end of the first side is inclined towards the second side, and the lower end of the second side is first inclined towards the first side and then extends vertically downward. An elongated air outlet is formed between the first and second sides. Chinese Patent Application No. 201922255776.9 discloses a cold air knife drying device. The disclosed cold air knife drying device includes a main body, on which an upper air knife mounting plate and a lower air knife mounting plate are provided. A hollow cylindrical connecting air pipe is provided inside the main body. A circular cylindrical air pipe fixing block is provided on the upper side of the connecting air pipe. The air pipe fixing block is located on the upper side of the main body. A plate-shaped upper air knife fixing plate is provided on the upper air knife mounting plate, and a plate-shaped lower air knife fixing plate is provided on the lower air knife mounting plate.

[0005] Traditional air knives, due to their simple internal airflow path design, are prone to turbulence and eddies, resulting in significant noise pollution and affecting the working environment and personnel health. In the aforementioned existing technologies, by setting an airflow regulating plate, when the airflow input to the air knife body is small, the airflow regulating plate can be moved towards the second side to reduce the diameter of the air outlet, thereby reducing the amount of air discharged from the air outlet. However, existing noise reduction solutions often sacrifice air pressure or airflow uniformity when optimizing the airflow path, resulting in reduced purging efficiency and energy waste. Utility Model Content

[0006] The present invention aims to overcome the defects in the prior art and provide a noise reduction air knife that can achieve graded noise reduction and airflow optimization in synergy.

[0007] To achieve the above-mentioned utility model objectives, the present utility model adopts the following technical solution: a noise-reducing air knife, comprising a housing, wherein the housing is provided with a noise-reducing structure for reducing noise in the airflow, the noise-reducing structure being provided with multiple sets of noise-reducing holes with gradually decreasing apertures along the airflow direction, and the apertures of each set of noise-reducing holes being equal; the bottom of the housing is provided with a nozzle for blowing out airflow, and the nozzle is provided with sound-absorbing cotton and a sound-absorbing plate that cooperates with the sound-absorbing cotton.

[0008] As a preferred embodiment of this utility model, the noise reduction structure is a hollow structure arranged along the length of the shell, and the two ends of the noise reduction structure are open.

[0009] As a preferred embodiment of this utility model, a plurality of the noise reduction holes are arranged in an array along the length direction of the noise reduction structure on the outer wall of the noise reduction structure.

[0010] As a preferred embodiment of this utility model, the end of the housing is provided with an air inlet that communicates with the noise reduction structure.

[0011] As a preferred embodiment of this utility model, both ends of the housing are provided with sealing plates for sealing the housing, and the sealing plates are provided with through holes that communicate with the air inlet.

[0012] As a preferred embodiment of this utility model, the nozzle includes two nozzle plates symmetrically arranged along the length of the shell, and an air outlet channel connected to the noise reduction hole is formed between the two nozzle plates.

[0013] As a preferred embodiment of this utility model, the bottom end of the nozzle plate is provided with an installation groove along the length direction of the nozzle plate, the bottom of the installation groove is provided with a fixing groove, the sound-absorbing cotton is placed in the fixing groove, and the sound-absorbing plate is placed in the installation groove.

[0014] As a preferred embodiment of this utility model, the sound-absorbing plate is provided with a plurality of sound-absorbing holes arranged in an array.

[0015] As a preferred embodiment of this utility model, the top of the nozzle plate is provided with an outwardly extending connecting portion, and the bottom of the housing is provided with an overlapping portion that cooperates with the connecting portion.

[0016] Compared with the prior art, the beneficial effects of this utility model are:

[0017] 1. A noise reduction structure is installed inside the housing to reduce airflow noise. The noise reduction structure has multiple sets of noise reduction holes with gradually decreasing diameters along the airflow direction, and the hole diameters in each set of noise reduction holes are the same. Through multiple sets of noise reduction holes with gradually decreasing diameters, the airflow velocity can be gradually adjusted. The Venturi effect is generated at each stage of hole diameter reduction, which reduces turbulent noise and maintains airflow kinetic energy, thus resolving the contradiction between noise reduction and wind pressure maintenance. At the same time, through the multiple sets of noise reduction holes, the uniformity and adaptability of airflow distribution are significantly improved when the airflow flows through several noise reduction holes.

[0018] 2. Furthermore, sound-absorbing cotton is installed in the air nozzle and fixed by a sound-absorbing plate. Sound-absorbing holes are set on the sound-absorbing plate to work with the sound-absorbing cotton to absorb the noise of the airflow passing through the air nozzle. By combining gradient hole fluid control and the sound-absorbing cotton with sound-absorbing holes and the sound-absorbing plate, active noise reduction and passive noise reduction are combined to form a dual noise suppression mechanism, thereby improving the noise reduction effect and efficiency.

[0019] 3. Furthermore, the two nozzle plates are symmetrically arranged, and an air outlet channel is formed between the two nozzle plates. The symmetrical nozzle plate and air outlet channel design, combined with the rectification effect of the gradient aperture on the airflow, improves the uniformity of the outlet airflow velocity distribution. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of this utility model;

[0021] Figure 2 This is an exploded view of the structure of this utility model;

[0022] Figure 3 This is a schematic diagram of the noise reduction structure of this utility model;

[0023] Figure 4 This is a schematic diagram of the aperture distribution of the noise reduction holes;

[0024] Figure 5 This is the front view of the nozzle;

[0025] Figure 6 This is a schematic diagram of the air nozzle plate;

[0026] Figure 7 This is a schematic diagram of the structure of sound-absorbing cotton;

[0027] Figure 8 This is a structural diagram of a sound-absorbing panel.

[0028] Reference numerals: housing 1, sealing plate 101, through hole 1011, air inlet 102, overlapping part 103, air nozzle 2, air nozzle plate 201, mounting groove 2011, fixing groove 2012, connecting part 2013, sound absorbing cotton 202, sound absorbing plate 203, sound absorbing hole 2031, air outlet channel 204, noise reduction structure 3, noise reduction hole 301. Detailed Implementation

[0029] The embodiments of this utility model will now be described in detail with reference to the accompanying drawings.

[0030] like Figures 1-8 As shown, a noise-reducing air knife includes a housing 1, inside which is a noise-reducing structure 3 for reducing noise in the airflow. The noise-reducing structure 3 has multiple sets of noise-reducing holes 301 with gradually decreasing apertures along the airflow direction, and the apertures of each set of noise-reducing holes 301 are equal. At the bottom of the housing 1, there is a nozzle 2 for blowing out airflow. The nozzle 2 has sound-absorbing cotton 202 and a sound-absorbing plate 203 that cooperates with the sound-absorbing cotton 202.

[0031] Furthermore, the shell 1 is hollow, and the noise reduction structure 3 is set at the top of the shell 1. Several noise reduction holes 301 are provided on the noise reduction structure 3. The noise reduction holes 301 are grouped to form several groups of noise reduction holes 301, and the groups of noise reduction holes 301 are arranged and distributed along the airflow direction. At the same time, the aperture of the noise reduction holes 301 in each group is the same, and the aperture of the noise reduction holes 301 in different groups decreases gradually along the airflow direction.

[0032] like Figure 4 As shown, specifically in this embodiment, several noise reduction holes 301 are divided into three groups, namely groups A, B, and C. The lengths of groups A, B, and C are the same. The direction of the arrow in the figure is the airflow direction. Groups A, B, and C are arranged along the airflow direction. The diameter of the noise reduction hole 301 in group A is larger than that in group B, and the diameter of the noise reduction hole 301 in group B is larger than that in group C.

[0033] By using multiple sets of noise reduction holes 301 with decreasing gradients, the airflow speed can be gradually adjusted. The Venturi effect is generated at each stage of hole reduction, which reduces turbulent noise and maintains airflow kinetic energy, thus resolving the contradiction between noise reduction and wind pressure maintenance. At the same time, by setting multiple sets of noise reduction holes 301, the uniformity and adaptability of airflow distribution are significantly improved when the airflow flows through several noise reduction holes.

[0034] The Venturi effect describes how, when a fluid flows through a gradually narrowing pipe, its velocity increases while its pressure decreases accordingly.

[0035] When the airflow enters from the pipe port, due to the sudden change in the pipe cross-section, that is, from a larger cross-section to a smaller cross-section, in this embodiment, although the cross-section of the noise reduction hole 301 is described here rather than the entire noise reduction structure 3, each noise reduction hole 301 constitutes a small "cross-section" change relative to the airflow, and the airflow will accelerate at the noise reduction hole 301.

[0036] The gradient decrease in aperture along the airflow direction means that as the airflow advances, the diameter of each subsequent set of noise reduction apertures 301 it encounters is smaller than the previous set of noise reduction apertures 301. This design causes the airflow to undergo an acceleration process as it passes through each set of noise reduction apertures 301.

[0037] According to Bernoulli's principle, an increase in flow velocity is accompanied by a decrease in pressure. Therefore, as the airflow passes through the noise reduction chamber 301 with decreasing apertures in each set, its pressure decreases accordingly. This pressure reduction helps to reduce turbulence and eddies in the airflow, as turbulence and eddies often require high energy to maintain. When the pressure decreases, these high-energy airflow phenomena are more easily suppressed or dissipated.

[0038] As mentioned earlier, a design with a decreasing aperture gradient helps reduce turbulence and eddies in the airflow. These phenomena are among the main causes of noise. By suppressing their generation, noise levels can be effectively reduced.

[0039] The decreasing aperture gradient also optimizes the airflow distribution within the noise reduction structure 3. As airflow passes through orifices of different sizes, it distributes more evenly around the noise reduction structure 3. This uniform airflow distribution helps reduce noise caused by uneven airflow.

[0040] As the airflow passes through each noise-reducing section 301, it undergoes an acceleration and decompression process. This process consumes the airflow's energy and converts it into heat or other forms of energy. Through multiple such energy conversion processes, high-energy components in the airflow (such as turbulence and eddies) are gradually dissipated, thereby reducing the noise level.

[0041] The noise reduction structure 3 is a hollow structure arranged along the length of the shell 1, and the two ends of the noise reduction structure 3 are open. A number of noise reduction holes 301 are arranged in an array along the length of the noise reduction structure 3 on the outer wall of the noise reduction structure 3. Furthermore, the noise reduction structure 3 is a cylindrical pipe, and the number of noise reduction holes 301 are evenly distributed on the pipe wall of the cylindrical pipe. The airflow enters from one end of the noise reduction structure 3 and flows out from the number of noise reduction holes 301.

[0042] The end of the housing 1 is provided with an air inlet 102 that is connected to the noise reduction structure 3. Furthermore, the air inlet 102 is located at one end of the housing 1, and the airflow enters the noise reduction structure 3 through the air inlet 102, and noise reduction of the airflow is achieved in the noise reduction structure 3.

[0043] Both ends of the housing 1 are provided with sealing plates 101 to seal the housing 1. The sealing plates 101 are provided with through holes 1011 that communicate with the air inlet 102. Furthermore, the sealing plates 101 are used to seal the housing 1, thereby preventing airflow from flowing out from both ends of the housing 1 and reducing the airflow at the nozzle 2. At the same time, the through holes 1011 are used to connect the air inlet 102 with the noise reduction structure 3, ensuring that the airflow from the air inlet 102 into the noise reduction structure 3 is not obstructed.

[0044] The nozzle 2 includes two nozzle plates 201 symmetrically arranged along the length of the housing 1. An air outlet channel 204 connected to the noise reduction hole 301 is formed between the two nozzle plates 201. Furthermore, the nozzle plates 201 are arranged along the length of the housing 1, and a gap is formed between the two nozzle plates 201. This gap forms the air outlet channel 204 for airflow to flow out. The symmetrical structure ensures the stability of the air outlet direction and avoids deviation caused by process quality fluctuations. At the same time, the narrow air outlet channel 204 enhances the laminar flow characteristics of the airflow and improves the uniformity of purging.

[0045] The bottom of the nozzle plate 201 is provided with an installation groove 2011 along the length of the nozzle plate 201. The bottom of the installation groove 2011 is provided with a fixing groove 2012. The sound-absorbing cotton 202 is placed in the fixing groove 2012, and the sound-absorbing plate 203 is placed in the installation groove 2011. At the same time, the sound-absorbing plate 203 is provided with a number of arrayed sound-absorbing holes 2031. Furthermore, the fixing groove 2012 precisely positions the sound-absorbing cotton 202, and the sound-absorbing plate 203 fixes the sound-absorbing cotton 202 to prevent noise reduction failure caused by displacement of the sound-absorbing cotton 202. The number of sound-absorbing holes 2031 provided on the sound-absorbing plate 203 are evenly distributed along the length of the sound-absorbing plate 203. The shape of the sound-absorbing holes 2031 can be rectangular or circular. The sound-absorbing cotton 202 absorbs the noise of the airflow at the nozzle 2, and the sound-absorbing holes 2031 facilitate the absorption of noise by the sound-absorbing cotton 202.

[0046] The top of the nozzle plate 201 is provided with an outwardly extending connecting portion 2013, and the bottom of the housing 1 is provided with an overlapping portion 103 that cooperates with the connecting portion 2013. Furthermore, the cross-sectional width of the two nozzle plates 201 gradually decreases from top to bottom. The connecting portion 2013 is provided along the length direction of the nozzle plate 201 and extends horizontally to the outside of the nozzle plate 201. The overlapping portion 103 at the bottom of the housing 1 extends into the housing 1. The overlapping portions 103 are located on opposite sides of the bottom of the housing 1, and a certain distance is formed between the two overlapping portions 103 for connecting the ventilation nozzle 2. The overlapping portion 103 overlaps on the corresponding connecting portion 2013.

[0047] The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention; therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0048] Although this document frequently uses reference numerals from the accompanying drawings, such as housing 1, sealing plate 101, through hole 1011, air inlet 102, overlapping part 103, nozzle 2, nozzle plate 201, mounting groove 2011, fixing groove 2012, connecting part 2013, sound-absorbing cotton 202, sound-absorbing plate 203, sound-absorbing hole 2031, air outlet duct 204, noise reduction structure 3, and noise reduction hole 301, the possibility of using other terms is not excluded. The use of these terms is merely for the convenience of describing and explaining the essence of this utility model; interpreting them as any additional limitation would contradict the spirit of this utility model.

Claims

1. A noise-reducing air knife, characterized in that, The device includes a housing (1), which contains a noise reduction structure (3) for reducing airflow noise. The noise reduction structure (3) has multiple sets of noise reduction holes (301) with decreasing apertures along the airflow direction. The apertures of each set of noise reduction holes (301) are equal. The bottom of the housing (1) is provided with a nozzle (2) for blowing out airflow. The nozzle (2) contains sound-absorbing cotton (202) and a sound-absorbing plate (203) that cooperates with the sound-absorbing cotton (202).

2. The noise-reducing air knife according to claim 1, characterized in that, The noise reduction structure (3) is a hollow structure arranged along the length of the shell (1), and the two ends of the noise reduction structure (3) are open.

3. The noise-reducing air knife according to claim 1, characterized in that, Several noise reduction holes (301) are arranged in an array along the length of the noise reduction structure (3) on the outer wall of the noise reduction structure (3).

4. The noise-reducing air knife according to claim 1, characterized in that, The end of the housing (1) is provided with an air inlet (102) that communicates with the noise reduction structure (3).

5. A noise-reducing air knife according to claim 4, characterized in that, Both ends of the housing (1) are provided with sealing plates (101) for sealing the housing (1), and the sealing plates (101) are provided with through holes (1011) that communicate with the air inlet (102).

6. The noise-reducing air knife according to claim 1, characterized in that, The nozzle (2) includes two nozzle plates (201) symmetrically arranged along the length of the housing (1), and an air outlet channel (204) connected to the noise reduction hole (301) is formed between the two nozzle plates (201).

7. A noise-reducing air knife according to claim 6, characterized in that, The bottom end of the nozzle plate (201) is provided with an installation groove (2011) along the length direction of the nozzle plate (201). The bottom of the installation groove (2011) is provided with a fixing groove (2012). The sound-absorbing cotton (202) is placed in the fixing groove (2012), and the sound-absorbing plate (203) is placed in the installation groove (2011).

8. A noise-reducing air knife according to claim 1, characterized in that, The sound-absorbing panel (203) is provided with a plurality of arrayed sound-absorbing holes (2031).

9. A noise-reducing air knife according to claim 6, characterized in that, The top of the nozzle plate (201) is provided with an outwardly extending connecting part (2013), and the bottom of the housing (1) is provided with an overlapping part (103) that cooperates with the connecting part (2013).

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