Current collector and centrifugal fan comprising same

Abstract

The utility model provides a current collector and a centrifugal fan including the current collector, the current collector comprises a drainage part and a flow guide part arranged on a second drainage section of the drainage part in a protruding mode, the section of the flow guide part is of an arc-shaped structure, and the section of the second drainage section is of an arc-shaped structure. The joint of the second drainage section and the first drainage section is a starting point, the end, away from the first drainage section, of the second drainage section is a terminal point, the included angle between the starting point and the terminal point is alpha 0, the included angle between the circle center connecting line of the flow guide part and the circle center of the second drainage section and the starting point is alpha 1, and 0.5 alpha 0 < = alpha 1 < = 0.7 alpha 0. When air flow enters the air inlet of the centrifugal fan from the current collector, the air flow is more attached to the current collector, the speed of the air flow is more stable, impact of the air flow on the volute annular wall is reduced, noise caused by violent impact of the air flow is reduced, and meanwhile the working capacity of an impeller is improved. In addition, the noise of the centrifugal fan is correspondingly reduced, and the noise reduction quality is improved.

Description

Technical Field

[0001] The utility model particularly relates to a collector and a centrifugal fan comprising the same. Background Art

[0002] Multi-blade centrifugal fans are widely used in various household appliances such as air conditioners, range hoods, air purifiers, ventilation fans, etc. due to their compact structure, high pressure coefficient, large flow coefficient and low noise.

[0003] A multi-blade centrifugal fan primarily consists of an inlet collector, impeller, and volute. Air is directed through the inlet collector to the impeller, where its pressure increases due to the impeller's rotation. The air ejected from the impeller is collected by the volute and directed to the volute outlet, where it is then piped or exhausted into the atmosphere. The inlet collector's primary function is to smoothly direct airflow toward the impeller inlet while minimizing air leakage during impeller operation.

[0004] For multi-blade centrifugal fans that use conventional air inlet collectors, the collector's profile is usually a combination of arcs and straight lines, with the end of the profile being a straight line in the same direction as the impeller axis. It provides poor guidance for the airflow at the fan inlet. When the airflow enters the impeller, only a small amount of airflow passes through the impeller tip area. The airflow mainly enters from the middle and rear area of the impeller and is then thrown into the volute flow channel. This will bring some problems. First, the gas is too concentrated when flowing out of the impeller, and the air flow velocity entering the volute flow channel will be too large. The impact of the air flow on the volute ring wall will be more severe, which will cause greater noise and vibration problems, and at the same time weaken the working ability of the impeller; secondly, after the air flow passes through the impeller and enters the volute flow channel, the pressure will increase, but because only a small amount of air flow passes through the impeller tip area, a low-pressure area will be formed on the outlet side of the impeller tip area. Under the action of the pressure difference, there will be backflow in the volute flow channel close to the volute front cover, and a large vortex will be generated, making the gas flow state in the volute flow channel more turbulent, and at the same time it will aggravate the gas leakage of the fan, which will manifest as increased fan noise and decreased fan noise quality. Utility Model Content

[0005] The technical problem to be solved by the present invention is to overcome the defects in the prior art that the airflow in the collector does not fit the inner wall of the collector and backflow is easily generated at the front cover of the volute, and to provide a collector and a centrifugal fan containing the same.

[0006] The utility model solves the above technical problems through the following technical solutions:

[0007] A collector, the collector comprising a drainage portion and a drainage portion protruding from a second drainage section of the drainage portion, the cross-section of the drainage portion being an arc-shaped structure, the cross-section of the second drainage section being an arc-shaped structure, the connection between the second drainage section and the first drainage section being a starting point, the end of the second drainage section away from the first drainage section being an end point, the angle between the starting point and the end point being α0, the angle between a line connecting the center of the drainage portion and the center of the second drainage section and the starting point being α1, and 0.5α0≤α1≤0.7α0.

[0008] In this solution, an arc-shaped guide portion is provided on the second guide section, and the center position of the guide portion forms an angle α1 with the starting point of the second guide section. The angle α1 and the angle α0 of the second guide section itself are in a quantitative relationship, so as to limit the setting position of the guide portion, and make the airflow fit better to the collector when the airflow enters the air inlet of the centrifugal fan from the collector, thereby introducing more airflow into the impeller of the centrifugal fan, and the airflow volume in the tip area of the impeller is increased. Compared with the traditional collector, the airflow at various positions of the impeller is more uniform when the gas flows out of the impeller, and the airflow velocity entering the volute flow channel is more stable, reducing the impact of the airflow on the volute ring wall, thereby reducing the noise caused by the violent impact of the airflow, and at the same time improving the working capacity of the impeller. In addition, after the air flow passes through the impeller and enters the volute flow channel, the pressure will increase. Due to the increase in the air flow in the impeller tip area, the low-pressure area originally formed on the outlet side of the impeller tip area is reduced or disappears, and the backflow and large vortex generated in the volute flow channel close to the volute front cover are reduced in a balanced way to balance the pressure difference, making the gas flow state in the volute flow channel more stable, the noise of the centrifugal fan is correspondingly reduced, and the noise reduction quality is improved.

[0009] Preferably, the arc curvature of the guide portion is greater than the arc curvature of the second guide section.

[0010] In this solution, the above-mentioned configuration ensures the effective flow guidance of the guide portion, allowing the airflow to adhere more closely to the collector. This also increases the volume of the inner area of the collector, providing more buffering for return leakage, reducing the impact of leakage and inlet airflow at the radial gap between the collector and the impeller, and improving noise quality.

[0011] Preferably, the cross-section of the first drainage section is a straight structure, and along the height direction of the collector, the distance between the top of the second drainage section and the top of the first drainage section is H0, and the distance between the top of the guide part and the top of the first drainage section is H1, and H1≥H0.

[0012] In this solution, through the above arrangement, the guide portion is limited along the height direction of the collector, thereby ensuring the effect of guiding the flow of the airflow.

[0013] Preferably, H1≤H0+3mm.

[0014] In this solution, the above arrangement is adopted to ensure that the dimension of the guide portion along the height direction of the collector is not too high, so as to avoid obstruction of the guided airflow.

[0015] Preferably, the radius of the second drainage section is R0, the radius of the guide portion is R1, and R1 ≥ 0.2R0.

[0016] In this solution, the above-mentioned arrangement is used to strengthen the fit between the guided airflow and the collector, thereby avoiding the generation of abnormal noise.

[0017] Preferably, R1≤0.5R0.

[0018] In this solution, the above arrangement is adopted to ensure that the size of the guide portion is not too large, thereby avoiding flow separation of the airflow.

[0019] Preferably, a mounting hole is further provided on the first drainage section, and the mounting hole is arranged at an edge of the first drainage section away from the second drainage section.

[0020] In this solution, the above arrangement allows the collector to be detachably connected to other structures, such as the volute of a centrifugal fan, which facilitates installation and does not hinder airflow.

[0021] A centrifugal fan comprises the collector as described above, wherein the collector is arranged at the volute inlet of the centrifugal fan.

[0022] In this solution, the centrifugal fan includes the above-mentioned collector and volute. The collector is detachably connected to the inlet of the volute to guide the airflow entering the volute, so that the airflow fits the flow of the collector. The airflow entering each position in the volute flow channel is more uniform, the flow rate is stable and the pressure difference is small. Therefore, under the same flow rate, the noise can be reduced by 0.2-0.3dB compared with traditional centrifugal fans.

[0023] Preferably, the distance between the edge of the guide portion close to the volute inlet and the volute inlet is w, and 0.5 mm < w < R0-R1.

[0024] In this solution, the above arrangement is used to limit the distance of the guide portion from the volute inlet in the radial direction, thereby preventing the airflow guided by the guide portion from being difficult to adhere to the outer surface of the collector again.

[0025] Preferably, the diameter of the volute inlet is 100-400 mm.

[0026] In this solution, the above-mentioned arrangement is used to utilize the collector to reduce the noise of centrifugal fans with a wider range of sizes.

[0027] The positive progressive effect of the present invention is that: the present invention sets an arc-shaped guide part on the second guide section, and the center position of the guide part forms an angle α1 with the starting point of the second guide section. The angle α1 and the angle α0 of the second guide section itself are in a quantitative relationship, so as to limit the setting position of the guide part, and make the airflow fit better to the collector when the airflow enters the air inlet of the centrifugal fan from the collector, thereby introducing more airflow into the impeller of the centrifugal fan, and the airflow volume in the tip area of the impeller is increased. Compared with the traditional collector, the airflow at various positions of the impeller is more uniform when the gas flows out of the impeller, and the airflow speed entering the volute flow channel is more stable, which reduces the impact of the airflow on the volute ring wall, thereby reducing the noise caused by the violent impact of the airflow, and at the same time improves the working capacity of the impeller. In addition, after the air flow passes through the impeller and enters the volute flow channel, the pressure will increase. Due to the increase in the air flow in the impeller tip area, the low-pressure area originally formed on the outlet side of the impeller tip area is reduced or disappears, and the backflow and large vortex generated in the volute flow channel close to the volute front cover are reduced in a balanced way to balance the pressure difference, making the gas flow state in the volute flow channel more stable, the noise of the centrifugal fan is correspondingly reduced, and the noise reduction quality is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a three-dimensional diagram of a centrifugal fan according to a preferred embodiment of the present invention.

[0029] Figure 2 This is a three-dimensional diagram of a current collector according to a preferred embodiment of the present invention.

[0030] Figure 3 This is a positional relationship diagram of the first drainage section and the second drainage section in a preferred embodiment of the present invention.

[0031] Figure 4 This is a diagram showing the positional relationship between the guide portion and the second guide section in a preferred embodiment of the present invention.

[0032] Description of reference numerals:

[0033] Current collector 10

[0034] Drainage 1

[0035] The first drainage section 11

[0036] Mounting hole 111

[0037] Second drainage section 12

[0038] Guide part 2

[0039] Volute 20 DETAILED DESCRIPTION

[0040] A preferred embodiment is given below, and the present invention is described more clearly and completely in conjunction with the accompanying drawings.

[0041] This embodiment provides a current collector 10, the specific structure of which is as follows Figure 1 、 Figure 2 、 Figure 3 and Figure 4 As shown, the collector 10 includes a drainage portion 1 and a drainage portion 2 protruding from the second drainage section 12 of the drainage portion 1. The cross-section of the drainage portion 2 is an arc-shaped structure, the cross-section of the second drainage section 12 is an arc-shaped structure, the connection between the second drainage section 12 and the first drainage section 11 is the starting point, the end of the second drainage section 12 away from the first drainage section 11 is the end point, the angle between the starting point and the end point is α0, the angle between the center of the drainage portion 2 and the center of the second drainage section 12 and the starting point is α1, and 0.5α0≤α1≤0.7α0.

[0042] Specifically, the collector 10 includes a first diversion section 11 and a second diversion section 12, which are integrally formed. The first diversion section 11 is used to connect to the volute 20 of the centrifugal fan, and the second diversion section 12 partially extends into the air inlet of the volute 20 to divert the airflow into the volute 20. From the cross-section, the second drainage section 12 is an arc-shaped structure, that is, a structure formed by an arc-shaped profile line. The guide part 2 is also an arc-shaped structure. The arc-shaped profile line of the guide part 2 protrudes from the arc-shaped profile line of the second drainage section 12, and the center positions of the two are different. Taking the center of the second drainage section 12 as the base point, the angle formed by the second drainage section 12 itself is α0, that is, the angle between the starting point and the center of the second drainage section 12 and the end point and the center of the second drainage section 12. Since the guide part 2 is set on the profile line of the second drainage section 12, its center is also located in the area enclosed by the second drainage section 12. The angle between the center of the guide part 2 and the center of the second drainage section 12 and the starting point is α1. It can be understood that α0 is greater than α1, and 0.5α0≤α1≤0.7α0. This determines the position of the center of the guide portion 2, and further determines the position of the contour of the guide portion 2 on the second guide section 12, that is, away from the first guide section 11 and close to the air inlet of the volute 20. In addition, compared to setting the guide portion 2 too close to the first guide section 11, considering the air intake distribution at the centrifugal fan inlet, the guide portion 2 set too close to the first guide section 11 can guide less airflow and cannot fully play its role. Compared to setting the guide portion too close to the end point, it is more difficult for the airflow guided by the guide portion 2 to reattach to the contour of the second guide section 12, which can easily cause significant flow separation and have a counterproductive effect.

[0043] It should be noted that, by arranging an arc-shaped guide portion 2 on the second guide section 12 and limiting the setting position of the guide portion 2, compared with the collector without the guide portion 2 on the second guide section 12, when the airflow is guided from the outer surface of the collector to the air inlet of the volute 20, the guide portion 2 turbulents the airflow, so that the airflow can be more closely attached to the outer surface of the second guide section of the collector, thereby introducing more airflow into the impeller of the centrifugal fan, and the airflow volume in the tip area of the impeller is increased. Compared with the traditional collector 10, when the gas flows out of the impeller, the airflow at various positions of the impeller is more uniform, and the airflow velocity entering the flow channel of the volute 20 is more stable, reducing the impact of the airflow on the annular wall of the volute 20, thereby reducing the noise caused by the violent impact of the airflow, and at the same time improving the working capacity of the impeller. In addition, after the air flow passes through the impeller and enters the flow channel of the volute 20, the pressure will increase. Due to the increase in the air flow rate in the tip area of the impeller, the low-pressure area originally formed on the outlet side of the tip area of the impeller is reduced or disappears, thereby balancing the pressure difference and reducing the backflow and large vortex in the flow channel of the volute 20 close to the front cover plate of the volute 20. This makes the gas flow state in the flow channel of the volute 20 more stable, the noise of the centrifugal fan is correspondingly reduced, and the noise reduction quality is improved.

[0044] Preferably, in this embodiment, the angle α0 is 186° and the angle α1 is 114°. The above angle values are obtained based on the finite element software analysis test in the prior art. When the center of the guide part 2 is located at the angle α1, the guide effect is better and the noise reduction effect is better. This is the prior art and will not be elaborated on here.

[0045] In this embodiment, the curvature of the guide portion 2 is greater than that of the second guide section 12. This strengthens the fit between the guided airflow and the collector 10, preventing abnormal noise. Furthermore, the provision of the guide portion 2 increases the volume of the area inside the second guide section 12, providing more buffering for the return leakage airflow, reducing the impact of the leakage airflow and the intake airflow at the radial gap between the collector 10 and the impeller, and thus improving noise quality.

[0046] In this embodiment, the cross-section of the first drainage section 11 is a straight structure. Along the height direction of the collector 10, the distance between the top of the second drainage section 12 and the top of the first drainage section 11 is H0, and the distance between the top of the guide part 2 and the top of the first drainage section 11 is H1, and H1≥H0.

[0047] Specifically, from a cross-sectional view, the first drainage section 11 is a flat plate formed by a straight line. The top of the first drainage section 11 is flat. The guide portion 2 protrudes from the second drainage section 12. At the same time, the height of the guide portion 2 along the height direction of the collector 10 is also higher than the second drainage section 12. However, it should be noted that the height of the guide portion 2 needs to be limited to a certain range to avoid the guide portion 2 being too high and obstructing the flow of air, thereby reducing its guiding effect on the airflow.

[0048] H1 can be equal to or greater than H0. Furthermore, H1 should not be too high. In this embodiment, H1 ≤ H0 + 3 mm. That is, the guide portion 2 should not be higher than 3 mm above the top of the second guide section 12 along the height direction of the collector 10 to ensure the effective flow guidance.

[0049] Preferably, in this embodiment, H0=7.7 mm, H1=8.2 mm. The above dimensions are obtained based on finite element software analysis tests in the prior art and will not be elaborated herein.

[0050] In this embodiment, the radius of the second drainage section 12 is R0, the radius of the drainage portion 2 is R1, and R1 ≥ 0.2R0.

[0051] Specifically, the radii of the guide portion 2 and the second guide section 12, both of which are arc-shaped structures, are numerically related. However, it is important to note that the radius of the guide portion 2 must be within a certain range to prevent excessively large guide portion 2 from obstructing the airflow and reducing its guiding effectiveness. R1 ≥ 0.2R0. Furthermore, R1 should not be too large; in this embodiment, R1 ≤ 0.5R0. This strengthens the alignment of the guided airflow with the collector 10, preventing abnormal noise and preventing flow separation.

[0052] Preferably, in this embodiment, R0=10.7 mm, R1=3 mm. The above dimensions are obtained based on finite element software analysis tests in the prior art and will not be elaborated on herein.

[0053] In this embodiment, a mounting hole 111 is further defined in the first drainage section 11 . The mounting hole 111 is located at an edge of the first drainage section 11 away from the second drainage section 12 .

[0054] Specifically, the mounting hole 111 passes through the first drainage section 11 and extends along the thickness direction of the first drainage section 11. The first drainage section 11 is connected to the volute 20 via a bolt assembly, which is passed through the mounting hole 111 to achieve the connection between the first drainage section 11 and the volute 20. Of course, in other embodiments, the collector 10 can also be detachably connected to other structures, such as the volute of an air conditioner. It is understandable that after the bolt assembly connects the first drainage section 11 to the volute 20, the portion of the bolt assembly located at the top of the first drainage section 11 has little effect on the airflow and can be ignored, thereby facilitating installation and not hindering the airflow.

[0055] In addition, a plurality of mounting holes 111 are provided at intervals to improve connection stability by increasing connection points during connection.

[0056] This embodiment further provides a centrifugal fan, which includes the above-mentioned collector 10. The collector 10 is arranged at the inlet of the volute 20 of the centrifugal fan.

[0057] Specifically, the inlet of the volute 20 is a circular hole, and the collector 10 is detachably connected to the inlet of the volute 20 to guide the airflow entering the volute 20, so that the airflow fits the flow of the collector 10, and the airflow entering each position of the flow channel of the volute 20 is more uniform, the flow rate is stable and the pressure difference is small, thereby reducing the noise by 0.2-0.3dB compared with traditional centrifugal fans under the same flow condition.

[0058] In this embodiment, the distance between the edge of the guide portion 2 close to the inlet of the volute 20 and the inlet of the volute 20 is w, and 0.5 mm < w < R0-R1.

[0059] Specifically, along the radial direction of the volute 20 inlet, the distance between the edge of the guide portion 2 near the volute 20 inlet and the volute 20 inlet is w, and 0.5 mm < w < R0-R1. This limits the radial distance of the guide portion 2 at the volute 20 inlet, ensuring that the distance between the guide portion 2 and the volute 20 inlet is moderate, avoiding situations where the value of w is too large or too small, making it difficult for the guided airflow to reattach to the outer surface of the collector 10.

[0060] Preferably, in this embodiment, w=0.8 mm. The above dimensions are obtained based on finite element software analysis tests in the prior art and will not be elaborated on herein.

[0061] In this embodiment, the diameter of the volute 20 at the inlet is 100-400 mm.

[0062] Specifically, the diameter D0 at the inlet of the volute 20 is 100-400mm, so that the collector 10 can be used to reduce the noise of centrifugal fans with a wider range of sizes. That is, the collector 10 can be applied to centrifugal fans of multiple sizes, and effectively reduce noise and improve noise quality. Preferably, in this embodiment, when R0 = 10.7mm, α0 = 186°, H0 = 7.7mm, R1 = 3mm, α1 = 114°, H1 = 8.2mm, and w = 0.8mm, according to the finite element software analysis in the prior art, D0 = 288.6mm has a more obvious noise reduction effect. The above dimensions are obtained based on test results and will not be elaborated on here.

[0063] Although specific embodiments of the present invention have been described above, those skilled in the art will appreciate that these are merely illustrative and that the scope of protection of the present invention is defined by the appended claims. Those skilled in the art may make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, and such changes and modifications are intended to fall within the scope of protection of the present invention.

Claims

1. A current collector, comprising a drainage portion and a drainage portion protruding from a second drainage section of the drainage portion, wherein the cross section of the drainage portion is an arc-shaped structure, characterized in that: The cross-section of the second drainage section is an arc-shaped structure, the connection point between the second drainage section and the first drainage section is the starting point, the end of the second drainage section away from the first drainage section is the end point, the angle between the starting point and the end point is α0, the angle between the center point of the guide part and the center point of the second drainage section and the starting point is α1, and 0.5α0≤α1≤0.7α0.

2. The current collector according to claim 1, wherein: The arc curvature of the guide portion is greater than the arc curvature of the second guide section.

3. The current collector according to claim 1, wherein: The cross-section of the first drainage section is a straight structure. Along the height direction of the collector, the distance between the top of the second drainage section and the top of the first drainage section is H0, and the distance between the top of the guide part and the top of the first drainage section is H1, and H1≥H0.

4. The current collector according to claim 3, characterized in that H1≤H0+3mm.

5. The current collector according to claim 4, characterized in that The radius of the second drainage section is R0, the radius of the guide portion is R1, and R1 ≥ 0.2R0.

6. The current collector according to claim 5, characterized in that R1≤0.5R0.

7. The current collector according to claim 1, wherein: The first drainage section is further provided with a mounting hole, and the mounting hole is arranged at an edge of the first drainage section away from the second drainage section.

8. A centrifugal fan, characterized in that: The centrifugal fan comprises the collector according to any one of claims 1 to 7, and the collector is arranged at the volute inlet of the centrifugal fan.

9. The centrifugal fan according to claim 8, wherein: The distance between the edge of the guide portion close to the volute inlet and the volute inlet is w, and 0.5 mm < w < R0-R1.

10. The centrifugal fan according to claim 9, wherein: The diameter of the volute inlet is 100-400 mm.

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