A noise-reducing centrifugal fan blade and an air conditioner

Abstract

The application discloses a noise reduction type centrifugal fan blade and an air conditioner, and relates to the technical field of air conditioners. The noise reduction type centrifugal fan blade comprises a fan blade. The fan blade is provided with a flange side, a front edge side, a concave edge side and a rear edge side which are connected in sequence, the cross section of the concave edge side is in an arc shape, and the cross section of the flange side is a fitting curve formed by three curves connected in sequence. Compared with the prior art, the noise reduction type centrifugal fan blade can reduce the noise generated during air outlet, improve the comfort of users, reduce the loss of air volume, increase the air outlet volume, and improve the air outlet efficiency.

Description

Technical Field

[0001] This invention relates to the field of air conditioning technology, and in particular to a noise-reducing centrifugal fan blade and an air conditioner. Background Technology

[0002] Currently, air conditioners typically utilize centrifugal fans to drive airflow, creating an exhaust airflow. A heat exchanger then exchanges heat with this airflow to achieve heating or cooling. Modern centrifugal fans often employ a multi-bladed forward-facing design, with blades of uniform thickness or no variation along their chord length. This results in high-speed rotation of the centrifugal blades during airflow output, causing pressure fluctuations in the surrounding air. These pressure fluctuations act on the volute casing, generating noise, reducing user comfort, and causing airflow loss, leading to low airflow efficiency. Summary of the Invention

[0003] The problem solved by this invention is how to reduce the noise generated during air output, improve user comfort, reduce air volume loss, increase air volume, and improve air output efficiency.

[0004] To solve the above problems, the technical solution of the present invention is implemented as follows:

[0005] In a first aspect, the present invention provides a noise-reducing centrifugal fan blade, comprising a fan blade having a flange side, a leading edge side, a concave edge side, and a trailing edge side connected end-to-end. The cross-section of the concave edge side is arc-shaped, and the cross-section of the flange side is a fitting curve formed by connecting three curve segments sequentially. The functional relationship of the fitting curve is as follows:

[0006]

[0007] Where x is in millimeters, the x-axis is the direction along the line connecting the two ends of the arc of the fan blade, from the leading edge to the trailing edge, and the y-axis is perpendicular to the x-axis, from the concave edge to the convex edge. The origin is the intersection of the arc of the fan blade and the leading edge. Compared with the prior art, the noise-reducing centrifugal fan blade provided by this invention, due to the use of a concave edge arranged in an arc shape and a convex edge arranged in a fitted curve, can reduce the noise generated during air outlet, improve user comfort, reduce air volume loss, increase air volume, and improve air outlet efficiency.

[0008] Furthermore, when x = 4.45, the distance between the concave and convex flange sides is the largest, and the thickness of the fan blade is the largest. The thickness of the fan blade gradually increases and then gradually decreases in the x-axis direction, so that the airflow passing through the fan blade first diffuses outward to both sides of the fan blade, and then approaches each other along the concave and convex flange sides, reducing air resistance and improving air outlet efficiency.

[0009] Furthermore, the noise-reducing centrifugal fan also includes a fixed ring, with the trailing edge connected to the fixed ring. Multiple fan blades are arranged in a ring array within the fixed ring. The multiple fan blades work together to drive airflow and create an exhaust airflow.

[0010] Furthermore, the number of fan blades ranges from 42 to 45. A reasonable number of fan blades can minimize noise while ensuring sufficient airflow.

[0011] Furthermore, an inlet installation angle is formed between the circle centered at the midpoint of the fixed ring and passing through the origin, and the arc of the fan blade. The range of the inlet installation angle is 65 degrees to 75 degrees. A reasonable inlet installation angle can effectively improve the static pressure ratio and isentropic efficiency of the fan blade while ensuring the air volume.

[0012] Furthermore, an outlet installation angle is formed between the circle centered at the midpoint of the fixing ring and passing through the intersection of the central arc of the fan blade and the trailing edge, and the central arc of the fan blade. The range of the outlet installation angle is 160 degrees to 175 degrees. A reasonable outlet installation angle can effectively increase the air volume, improve the air outlet efficiency, and reduce the generated noise.

[0013] Furthermore, the difference between the outlet installation angle and the inlet installation angle ranges from 90 degrees to 105 degrees. A reasonable difference between the outlet installation angle and the inlet installation angle can minimize noise generation while ensuring airflow performance, and also facilitates the manufacturing of noise-reducing centrifugal fan blades.

[0014] Furthermore, the ratio of the diameter of the circle centered at the midpoint of the fixed ring and passing through the origin to the outer diameter of the fixed ring ranges from 0.78 to 0.85. A reasonable wheel diameter ratio can increase the air volume, improve air outlet efficiency, and reduce the generated noise.

[0015] Furthermore, the cross-section of the leading edge is arc-shaped, with the radius of the arc ranging from 0.5 mm to 0.7 mm. A reasonable radius of the arc on the leading edge can minimize air resistance while ensuring airflow guidance.

[0016] Secondly, the present invention provides an air conditioner including the aforementioned noise-reducing centrifugal fan blade. The noise-reducing centrifugal fan blade includes a fan blade with a flange side, a leading edge side, a concave edge side, and a trailing edge side connected end-to-end. The cross-section of the concave edge side is arc-shaped, and the cross-section of the flange side is a fitting curve formed by connecting three curve segments sequentially. The functional relationship of the fitting curve is:

[0017]

[0018] Where x is in millimeters, the x-axis is the direction along the line connecting the two ends of the central arc of the fan blade, from the leading edge to the trailing edge, and the y-axis is perpendicular to the x-axis, from the concave edge to the convex edge. The origin is the intersection of the central arc of the fan blade and the leading edge. Air conditioners can reduce noise generated during airflow, improve user comfort, reduce airflow loss, increase airflow volume, and improve airflow efficiency. Attached Figure Description

[0019] Figure 1 This is a front view of the noise-reducing centrifugal fan blade described in the first embodiment of the present invention;

[0020] Figure 2 This is a schematic diagram of the connection between the fan blade and the fixing ring in the noise-reducing centrifugal fan blade according to the first embodiment of the present invention;

[0021] Figure 3 This is a mathematical model diagram of the connection between the fan blade and the fixed ring in the noise-reducing centrifugal fan blade described in the first embodiment of the present invention;

[0022] Figure 4 This is a mathematical model diagram of the flange side of the fan blade in the noise-reducing centrifugal fan blade described in the first embodiment of the present invention;

[0023] Figure 5 This is another mathematical model diagram of the connection between the fan blade and the fixed ring in the noise-reducing centrifugal fan blade described in the first embodiment of the present invention;

[0024] Figure 6 This is a mathematical model diagram of the noise-reducing centrifugal fan blade described in the first embodiment of the present invention;

[0025] Figure 7 This is an axonometric view of the noise-reducing centrifugal fan blade described in the first embodiment of the present invention;

[0026] Figure 8 This is a schematic diagram of the structure of the first and second blades of the noise-reducing centrifugal fan blade described in the first embodiment of the present invention, which are arranged in a staggered manner.

[0027] Explanation of reference numerals in the attached figures:

[0028] 100 - Noise-reducing centrifugal fan blade; 110 - Fan blade; 111 - Flange side; 112 - Leading edge side; 113 - Concave edge side; 114 - Trailing edge side; 115 - First fan blade; 116 - Second fan blade; 120 - Fixing ring; 121 - First fixing ring; 122 - Second fixing ring. Detailed Implementation

[0029] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0030] First Embodiment

[0031] Please refer to Figure 1 This invention provides a noise-reducing centrifugal fan blade 100 for driving airflow to form an exhaust airflow. It can reduce noise generated during airflow, improve user comfort, reduce airflow loss, increase airflow volume, and improve airflow efficiency.

[0032] It should be noted that the noise-reducing centrifugal fan blade 100 is used in a centrifugal fan (not shown in the figure). The centrifugal fan includes a drive motor (not shown in the figure) and the noise-reducing centrifugal fan blade 100. The drive motor is connected to the noise-reducing centrifugal fan blade 100 for transmission. The drive motor can drive the noise-reducing centrifugal fan blade 100 to rotate, so that the noise-reducing centrifugal fan blade 100 generates negative pressure and drives the air flow to form an exhaust airflow.

[0033] Please refer to the reference. Figure 2 , Figure 3 and Figure 4 The noise-reducing centrifugal fan blade 100 includes a fan blade 110 and a fixing ring 120. The fan blade 110 is fixedly connected within the fixing ring 120, which can fix the position of the fan blade 110. The fan blade 110 is bent to guide airflow, reduce air resistance, and improve air output efficiency. Specifically, the fan blade 110 is provided with a flange side 111, a leading edge side 112, a concave edge side 113, and a trailing edge side 114 connected end to end. The trailing edge side 114 is connected to the fixing ring 120. The concave edge side 113 is the side of the fan blade 110 that is recessed inward, the flange side 111 is the side of the fan blade 110 that is protruding outward, and the leading edge side 112 is the side of the fan blade 110 away from the fixing ring 120. The cross-section of the concave edge side 113 is arc-shaped, and the cross-section of the flange side 111 is a fitted curve formed by connecting three curve segments in sequence.

[0034] It is worth noting that the central angle of the arc formed by the concave edge 113 ranges from 90 degrees to 110 degrees. A reasonable central angle of the concave edge 113 can facilitate processing and production while ensuring that the concave edge 113 has sufficient arc length to guide airflow, thereby improving the air guiding effect and reducing the generated noise. For ease of understanding, the arc formed by the concave edge 113 is represented as segment ab, and the central angle of the arc formed by the concave edge 113 is represented as A. In this embodiment, the central angle of the arc formed by the concave edge 113 is 100 degrees, but it is not limited to this. In other embodiments, the central angle of the arc formed by the concave edge 113 can be 90 degrees or 110 degrees. The size of the central angle of the arc formed by the concave edge 113 is not specifically limited.

[0035] It should be noted that the functional relationship of the fitting curve formed by the cross-section of flange side 111 is as follows:

[0036]

[0037] Where x is in millimeters, the x-axis is the direction along the line connecting the two ends of the arc of the fan blade 110, from the leading edge 112 to the trailing edge 114, the y-axis is perpendicular to the x-axis, and runs from the concave edge 113 to the convex edge 111. The origin is the intersection of the arc of the fan blade 110 and the leading edge 112. For ease of understanding, the origin is represented as point o.

[0038] Specifically, as shown in the above functional relationship, the cross-section of the flange side 111 includes a first curved segment, a second curved segment, and a third curved segment connected in sequence. The first curved segment is positioned away from the fixed ring 120, while the third curved segment is positioned close to the fixed ring 120. The entire cross-section of the flange side 111 has a parabolic shape, which better adapts to changes in the flow field and reduces air resistance. For ease of understanding, the first curved segment is denoted as segment cd, the second curved segment as segment de, and the third curved segment as segment ef. During the airflow process of the noise-reducing centrifugal fan blade 100, the airflow on the flange side 111 flows from the first curved segment along the second curved segment and towards the third curved segment, resulting in a better velocity distribution on the surface of the flange side 111. This improves the separation and development of the air adsorption layer on the surface of the fan blade 110, effectively reduces air resistance, increases airflow efficiency, and reduces vortex noise within the volute component, making the flow field distribution more uniform.

[0039] In this embodiment, the flange side 111 has an eccentric structure, and the thickness of the fan blade 110 gradually increases and then gradually decreases in the x-axis direction. This allows the airflow passing through the fan blade 110 to first diffuse outwards to both sides of the fan blade 110, and then approach each other along the concave flange side 113 and the flange side 111, reducing air resistance and improving air outlet efficiency. When x = 4.45, the distance between the concave flange side 113 and the flange side 111 is the largest, and the thickness of the fan blade 110 is the largest.

[0040] In this embodiment, the cross-section of the leading edge side 112 is arc-shaped to facilitate the guidance of airflow to the concave edge side 113 and the convex edge side 111, thereby reducing air resistance and improving the air guiding effect. It can be understood that the arc of the leading edge side 112 is represented by segment ac, which is the portion of the profile where the concave edge side 113 and the convex edge side 111 connect at the end away from the fixing ring 120; the arc of the trailing edge side 114 is represented by segment bf, which is the portion of the profile where the concave edge side 113 and the convex edge side 111 connect at the end near the fixing ring 120.

[0041] Furthermore, the radius of the arc formed by the leading edge side 112 ranges from 0.5 mm to 0.7 mm. A reasonable radius of the arc formed by the leading edge side 112 can minimize air resistance while ensuring the air guiding effect. For ease of understanding, the radius of the arc formed by the leading edge side 112 is denoted as R. In this embodiment, the radius of the arc formed by the leading edge side 112 is 0.6 mm, but it is not limited to this. In other embodiments, the radius of the arc formed by the leading edge side 112 can be 0.5 mm or 0.7 mm, and the size of the radius of the arc formed by the leading edge side 112 is not specifically limited.

[0042] It should be noted that there are multiple fan blades 110, arranged in a circular array within the fixed ring 120. These multiple blades work together to drive airflow and create an exhaust airflow. Specifically, the number of fan blades 110 ranges from 42 to 45. A suitable number of fan blades 110 can minimize noise while ensuring sufficient airflow. In this embodiment, there are 43 fan blades 110, but this is not a limitation. In other embodiments, the number of fan blades 110 can be 42 or 45; the number of fan blades 110 is not specifically limited.

[0043] Please refer to Figure 5 It is worth noting that the inlet installation angle is formed between the circle centered at the midpoint of the fixed ring 120 and passing through the origin, and the arc of the fan blade 110. Specifically, the inlet installation angle is formed between the tangent of this circle at the origin and the tangent of the arc of the fan blade 110 at the origin. The range of the inlet installation angle is 65 degrees to 75 degrees. A reasonable inlet installation angle can effectively improve the static pressure ratio and isentropic efficiency of the fan blade 110 while ensuring the airflow. For ease of understanding, the inlet installation angle is denoted as B. In this embodiment, the inlet installation angle is 90 degrees, but it is not limited to this. In other embodiments, the inlet installation angle can be 65 degrees or 75 degrees; the size of the inlet installation angle is not specifically limited.

[0044] Furthermore, an outlet installation angle is formed between the circle centered at the midpoint of the fixing ring 120 and passing through the intersection of the arc of the fan blade 110 and the trailing edge side 114, and the arc of the fan blade 110. Specifically, the outlet installation angle is formed between the tangent of this circle at the intersection and the tangent of the arc of the fan blade 110 at the intersection. The range of the outlet installation angle is 160 degrees to 175 degrees. A reasonable outlet installation angle can effectively increase the air volume, improve airflow efficiency, and reduce noise. For ease of understanding, the outlet installation angle is denoted as C. In this embodiment, the outlet installation angle is 168 degrees, but it is not limited to this. In other embodiments, the outlet installation angle can be 160 degrees or 175 degrees; the size of the outlet installation angle is not specifically limited.

[0045] It should be noted that the difference between the outlet installation angle and the inlet installation angle ranges from 90 degrees to 105 degrees. A reasonable difference between the outlet and inlet installation angles can minimize noise while ensuring airflow performance and facilitate the processing of the noise-reducing centrifugal fan blade 100. In this embodiment, the difference between the outlet and inlet installation angles is 98 degrees, but it is not limited to this. In other embodiments, the difference between the outlet and inlet installation angles can be 90 degrees or 105 degrees; the magnitude of the difference is not specifically limited.

[0046] Please refer to Figure 6 It is worth noting that the ratio of the diameter of the circle centered at the midpoint of the fixed ring 120 and passing through the origin to the outer diameter of the fixed ring 120 ranges from 0.78 to 0.85. That is, the wheel diameter ratio of the noise-reducing centrifugal fan 100 ranges from 0.78 to 0.85. A reasonable wheel diameter ratio can increase the airflow, improve airflow efficiency, and reduce the generated noise. For ease of understanding, the diameter of the circle centered at the midpoint of the fixed ring 120 and passing through the origin is denoted as D, and the outer diameter of the fixed ring 120 is denoted as E. In this embodiment, the wheel diameter ratio of the noise-reducing centrifugal fan 100 is 0.82, but it is not limited to this. In other embodiments, the wheel diameter ratio of the noise-reducing centrifugal fan 100 can be 0.78 or 0.85; the size of the wheel diameter ratio of the noise-reducing centrifugal fan 100 is not specifically limited.

[0047] Please refer to the reference. Figure 7 and Figure 8 The fan blade 110 includes a first fan blade 115 and a second fan blade 116. There are multiple first fan blades 115 and multiple second fan blades 116, all disposed within the fixing ring 120. Specifically, the first fan blades 115 and the second fan blades 116 have the same shape, and are staggered. This staggered arrangement effectively improves the air outlet efficiency and increases the air volume of the noise-reducing centrifugal fan blade 100.

[0048] The fixing ring 120 includes a first fixing ring 121 and a second fixing ring 122 coaxially arranged. The first fixing ring 121 and the second fixing ring 122 have the same diameter. A plurality of first fan blades 115 are arranged in a ring array within the first fixing ring 121, and a plurality of second fan blades 116 are arranged in a ring array within the second fixing ring 122. During the process of the drive motor driving the noise-reducing centrifugal fan blade 100 to rotate, the first fixing ring 121 and the second fixing ring 122 rotate synchronously to drive the first fan blades 115 and the second fan blades 116 to move, thereby realizing the air outlet function.

[0049] Furthermore, in the circumferential direction of the fixed ring 120, the ratio of the angle at which the first blade 115 rotates to the position of an adjacent second blade 116 to the angle at which the second blade 116 rotates to the position of an adjacent first blade 115 ranges from 0.5 to 0.7. That is, on the cross-section of the noise-reducing centrifugal fan 100, a second blade 116 is located between two adjacent first blades 115, wherein the ratio of the angle between the first first blade 115 and the second blade 116 to the angle between the second blade 116 and the second first blade 115 ranges from 0.5 to 0.7. Specifically, this angle ratio is called the tooth offset ratio of the noise-reducing centrifugal fan 100. A reasonable tooth offset ratio can effectively improve airflow efficiency and reduce wind noise. For ease of understanding, the angle at which the first blade 115 rotates to the position of an adjacent second blade 116 is denoted as F, and the angle at which the second blade 116 rotates to the position of an adjacent first blade 115 is denoted as G.

[0050] In this embodiment, the misalignment ratio is 0.6, that is, in the circumferential direction of the fixed ring 120, the ratio of the angle at which the first blade 115 rotates to the position of the adjacent second blade 116 to the angle at which the second blade 116 rotates to the position of the adjacent first blade 115 is 0.6. However, it is not limited to this. In other embodiments, the misalignment ratio can be 0.5 or 0.7. The size of the misalignment ratio is not specifically limited.

[0051] In this embodiment, the spacing between two adjacent first blades 115 is equal to the spacing between two adjacent second blades 116, that is, the number of first blades 115 in the first fixing ring 121 is equal to the number of second blades 116 in the second fixing ring 122. Specifically, the spacing between two adjacent first blades 115 ranges from 9.5 mm to 10.5 mm. A reasonable spacing between two adjacent first blades 115 can maximize the airflow while ensuring the air guiding effect. For ease of understanding, the spacing between two adjacent first blades 115 is denoted as H. In this embodiment, the spacing between two adjacent first blades 115 is 9.9 mm, but it is not limited to this. In other embodiments, the spacing between two adjacent first blades 115 can be 9.5 mm or 10.5 mm, and the size of the spacing between two adjacent first blades 115 is not specifically limited.

[0052] The noise-reducing centrifugal fan blade 100 of this embodiment has a fan blade 110 with a flange side 111, a leading edge side 112, a concave edge side 113, and a trailing edge side 114 connected end to end. The cross-section of the concave edge side 113 is arc-shaped, and the cross-section of the flange side 111 is a fitting curve formed by connecting three curve segments in sequence. The functional relationship of the fitting curve is as follows:

[0053]

[0054] Where x is in millimeters, the x-axis is the direction along the line connecting the two ends of the arc of the fan blade 110, from the leading edge 112 to the trailing edge 114, and the y-axis is perpendicular to the x-axis, from the concave edge 113 to the convex edge 111. The origin is the intersection of the arc of the fan blade 110 and the leading edge 112. Compared with the prior art, the noise-reducing centrifugal fan blade 100 provided by the present invention, due to the use of the concave edge 113 arranged in an arc shape and the convex edge 111 arranged in a fitted curve, can reduce the noise generated during air outlet, improve user comfort, reduce air volume loss, increase air volume, and improve air outlet efficiency.

[0055] Second Embodiment

[0056] This invention provides an air conditioner (not shown) for regulating indoor temperature. The air conditioner includes a heat exchanger (not shown) and a centrifugal fan. The centrifugal fan includes a drive motor and a noise-reducing centrifugal fan blade 100, with the drive motor connected to the noise-reducing centrifugal fan blade 100. The basic structure, principle, and technical effects of the noise-reducing centrifugal fan blade 100 are the same as in the first embodiment. For brevity, any parts not mentioned in this embodiment can be referred to the corresponding content in the first embodiment.

[0057] In this embodiment, the position of the heat exchanger corresponds to the position of the centrifugal fan. When the air conditioner is running, the drive motor can drive the noise-reducing centrifugal fan blade 100 to rotate, thereby generating negative pressure and driving airflow to form an outlet airflow. This outlet airflow can pass through the heat exchanger and blow into the room. During this process, the heat exchanger can heat or cool the outlet airflow to achieve the function of regulating the indoor temperature.

[0058] The beneficial effects of the air conditioner described in this embodiment are the same as those of the first embodiment, and will not be repeated here.

[0059] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A noise-reducing centrifugal fan blade, characterized in that, The fan blade (110) includes a flange side (111), a leading edge side (112), a concave edge side (113), and a trailing edge side (114) connected end to end. The concave edge side (113) has an arc-shaped cross-section, and the flange side (111) has a cross-section formed by connecting three curve segments in sequence to form a fitted curve. The functional relationship of the fitted curve is as follows: Where x is in millimeters, the x-axis is the direction on the line connecting the two ends of the arc of the fan blade (110) from the leading edge side (112) to the trailing edge side (114), the y-axis is perpendicular to the x-axis and from the concave edge side (113) to the convex edge side (111), and the origin is the intersection of the arc of the fan blade (110) and the leading edge side (112).

2. The noise-reducing centrifugal fan blade according to claim 1, characterized in that, When x = 4.45, the distance between the concave side (113) and the convex side (111) is the largest, and the thickness of the fan blade (110) is the largest.

3. The noise-reducing centrifugal fan blade according to claim 1, characterized in that, The noise-reducing centrifugal fan blade also includes a fixing ring (120), the trailing edge side (114) is connected to the fixing ring (120), and there are multiple fan blades (110), which are arranged in a ring array within the fixing ring (120).

4. The noise-reducing centrifugal fan blade according to claim 3, characterized in that, The number of fan blades (110) ranges from 42 to 45.

5. The noise-reducing centrifugal fan blade according to claim 3, characterized in that, An inlet mounting angle is formed between the circle with the midpoint of the fixing ring (120) as the center and passing through the origin and the arc of the fan blade (110), and the range of the inlet mounting angle is 65 degrees to 75 degrees.

6. The noise-reducing centrifugal fan blade according to claim 5, characterized in that, An outlet mounting angle is formed between the circle centered at the midpoint of the fixing ring (120) and passing through the intersection of the arc of the fan blade (110) and the trailing edge side (114) and the arc of the fan blade (110), and the outlet mounting angle is in the range of 160 degrees to 175 degrees.

7. The noise-reducing centrifugal fan blade according to claim 6, characterized in that, The difference between the outlet installation angle and the inlet installation angle ranges from 90 degrees to 105 degrees.

8. The noise-reducing centrifugal fan blade according to claim 3, characterized in that, The ratio of the diameter of the circle centered at the midpoint of the fixed ring (120) and passing through the origin to the outer diameter of the fixed ring (120) is in the range of 0.78 to 0.

85.

9. The noise-reducing centrifugal fan blade according to claim 1, characterized in that, The cross-section of the leading edge side (112) is arc-shaped, and the radius of the arc formed by the leading edge side (112) ranges from 0.5 mm to 0.7 mm.

10. An air conditioner, characterized in that, Including the noise-reducing centrifugal fan blade as described in any one of claims 1 to 9.

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