Centrifugal fan blade and air conditioner

Abstract

The application discloses a centrifugal fan blade and an air conditioner, and relates to the technical field of air conditioners. The centrifugal fan blade comprises a fixing ring and a blade. The blade is fixedly connected to the fixing ring, and the blade is oppositely provided with a concave flange side and a convex flange side. The cross section of the concave flange side comprises at least two circular arcs with different radii and sequentially connected. The cross section of the convex flange side is a fitting curve formed by four curves or straight lines sequentially connected. Compared with the prior art, the centrifugal fan blade provided by the application can reduce the noise generated during the operation of the centrifugal fan blade, increase the air volume, improve the air outlet efficiency, and improve the user experience.

Description

Technical Field

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

[0002] Currently, air conditioners typically use centrifugal fans to exchange heat between the airflow and the refrigerant in the heat exchanger to achieve cooling or heating. During this process, a large amount of airflow passes through the centrifugal fan blades, making the centrifugal fan blades the main factor affecting noise generation in air conditioners.

[0003] Most centrifugal fan blades nowadays adopt a multi-blade forward-curving design, with the blade profile in cross-section consisting of a single circular arc. The blades have a uniform thickness or no variation along the chord length, which causes pressure fluctuations in the surrounding gas during operation. The air pressure acts on the volute components, generating noise and causing a certain amount of airflow loss, resulting in low air output efficiency and affecting the user experience. Summary of the Invention

[0004] The problem solved by this invention is how to reduce the noise generated when the centrifugal fan blades are running, increase the air volume, improve the air output efficiency, and enhance the user experience.

[0005] To solve the above problems, the technical solution of the present invention is implemented as follows:

[0006] In a first aspect, the present invention provides a centrifugal fan blade, comprising a fixed ring and blades, the blades being fixedly connected within the fixed ring, and the blades having a concave flange side and a convex flange side disposed opposite to each other. The cross-section of the concave flange side includes at least two arc segments with different radii connected in sequence, and the cross-section of the convex flange side is a fitted curve formed by four curves or straight lines connected in sequence, the functional relationship of the fitted curve being:

[0007]

[0008] Where x is in millimeters, the x-axis is the direction along the line connecting the two ends of the blade's mid-arc line from the blade to the fixing ring, the y-axis is perpendicular to the x-axis from the concave flange side to the convex flange side, and the origin is the endpoint of the blade's mid-arc line away from the fixing ring. Compared with the prior art, the centrifugal fan blade provided by this invention, due to the use of a concave flange side composed of at least two circular arcs and a convex flange side in the shape of a fitted curve, can reduce the noise generated during the operation of the centrifugal fan blade, increase the air volume, improve the air outlet efficiency, and enhance the user experience.

[0009] Furthermore, when x = 2.5, the distance between the concave and convex flange sides is the largest, and the blade thickness is the largest. The blade thickness gradually increases and then gradually decreases in the x-axis direction, so that the airflow passing through the blade first diffuses outward to both sides of the blade, and then approaches each other along the concave and convex flange sides, reducing air resistance and improving air outlet efficiency.

[0010] Furthermore, when x = 5, the distance between the two ends of the line connecting the flange side and the arc of the blade is the largest.

[0011] Furthermore, the cross-section of the concave flange side includes a first arc and a second arc connected in sequence. The second arc is positioned between the fixing ring and the first arc, and the ratio of the radius of the second arc to the radius of the first arc ranges from 1.52 to 1.7. A reasonable ratio of the radius of the second arc to the radius of the first arc can improve the airflow guiding effect, thereby increasing the air volume and improving the airflow efficiency.

[0012] Furthermore, the central angle of the first arc ranges from 70 degrees to 83 degrees. A reasonable central angle of the first arc ensures that the arc has sufficient length to guide the airflow, thereby improving the airflow guiding effect.

[0013] Furthermore, the end of the blade furthest from the fixing ring is provided with a leading edge side, and the concave edge side is connected to the convex edge side through the leading edge side. The cross-section of the leading edge side is a third circular arc, and the radius of the third circular arc ranges from 0.5 mm to 0.7 mm. A reasonable radius of the third circular arc can minimize air resistance while ensuring air guiding effect.

[0014] Furthermore, an inlet installation angle is formed between the circle centered at the midpoint of the fixed ring and the distance between the midpoint of the fixed ring and the origin, and the mid-arc line of the blade. The range of the inlet installation angle is 60 degrees to 70 degrees. A reasonable inlet installation angle can effectively improve the static pressure ratio and isentropic efficiency of the blade while ensuring the air volume.

[0015] Furthermore, the blades include multiple first blades and multiple second blades. The fixing rings include a first fixing ring and a second fixing ring arranged coaxially. Multiple first blades are arranged in a circular array within the first fixing ring, and multiple second blades are arranged in a circular array within the second fixing ring. The first and second blades are staggered. In the circumferential direction of the fixing rings, the ratio of the angle at which a first blade rotates to the position of an adjacent second blade to the angle at which a second blade rotates to the position of an adjacent first blade ranges from 0.5 to 0.7. A reasonable stagger ratio can effectively improve airflow efficiency and reduce wind noise.

[0016] Furthermore, the spacing between two adjacent first blades is equal to the spacing between two adjacent second blades, and the spacing between two adjacent first blades ranges from 9.5 mm to 10.5 mm. A reasonable spacing between two adjacent first blades can maximize the airflow while ensuring effective air guidance.

[0017] Secondly, the present invention provides an air conditioner including the aforementioned centrifugal fan blade. The centrifugal fan blade includes a fixed ring and blades, the blades being fixedly connected within the fixed ring. The blades are provided with a concave flange side and a convex flange side opposite to each other. The cross-section of the concave flange side includes at least two arc segments with different radii connected in sequence. The cross-section of the convex flange side is a fitted curve formed by four curves or straight lines connected in sequence. The functional relationship of the fitted curve is:

[0018]

[0019] Where x is in millimeters, the x-axis is the direction along the line connecting the two ends of the blade's mid-curve and extending from the blade to the retaining ring, the y-axis is perpendicular to the x-axis and extends from the concave side to the convex side, and the origin is the endpoint of the blade's mid-curve away from the retaining ring. Air conditioners can reduce the noise generated by the centrifugal fan blades during operation, increase airflow, improve airflow efficiency, and enhance the user experience. Attached Figure Description

[0020] Figure 1 This is a front view of the centrifugal fan blade described in the first embodiment of the present invention;

[0021] Figure 2 This is a schematic diagram of the connection between the fixing ring and the blade in the centrifugal fan blade according to the first embodiment of the present invention from one perspective;

[0022] Figure 3 This is a mathematical model diagram of the connection between the fixing ring and the blade in the centrifugal fan blade according to the first embodiment of the present invention;

[0023] Figure 4 This is a mathematical model diagram of the flange side of the blade in the centrifugal fan blade described in the first embodiment of the present invention;

[0024] Figure 5 This is a schematic diagram of the connection between the fixing ring and the blade in the centrifugal fan blade according to the first embodiment of the present invention from another perspective;

[0025] Figure 6 This is an axonometric view of the centrifugal fan blade described in the first embodiment of the present invention;

[0026] Figure 7 This is a schematic diagram of the structure of the centrifugal fan blade in the first embodiment of the present invention, showing the first blade and the second blade being misaligned.

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

[0028] 100 - Centrifugal fan blade; 110 - Fixing ring; 111 - First fixing ring; 112 - Second fixing ring; 120 - Blade; 121 - Concave flange side; 122 - Protruding flange side; 123 - Leading edge side; 124 - First blade; 125 - Second blade. 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 centrifugal fan blade 100 for generating negative pressure to drive airflow and form an exhaust airflow. It can reduce the noise generated during the operation of the centrifugal fan blade 100, increase the airflow volume, improve airflow efficiency, and enhance the user experience.

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

[0033] Please refer to the reference. Figure 2 , Figure 3 and Figure 4 The centrifugal fan blade 100 includes a fixing ring 110 and blades 120. The blades 120 are fixedly connected within the fixing ring 110, which secures the position of the blades 120. The blades 120 are bent to guide airflow, reduce air resistance, and improve airflow efficiency. Specifically, the blades 120 have a concave flange side 121 and a convex flange side 122. The concave flange side 121 is the side of the blade 120 that is recessed inwards, and the convex flange side 122 is the side of the blade 120 that is protruding outwards. The cross-section of the concave flange side 121 includes at least two arc segments with different radii connected sequentially, and the cross-section of the convex flange side 122 is a fitted curve formed by four consecutive curves or straight lines.

[0034] In this embodiment, the cross-section of the concave flange side 121 includes a first arc and a second arc connected in sequence. The second arc is disposed between the fixing ring 110 and the first arc, and the centers of both the first and second arcs are located on the side of the concave flange side 121 away from the convex flange side 122. For ease of understanding, the first arc is represented as segment ab, and the second arc is represented as segment bc. During the airflow process of the centrifugal fan blade 100, the airflow flows from the first arc to the second arc on the concave flange side 121. However, this is not the only embodiment. In other embodiments, the cross-section of the concave flange side 121 may include three or four arc segments connected in sequence, and the number of arc segments forming the concave flange side 121 is not specifically limited.

[0035] It should be noted that the ratio of the radius of the second arc to the radius of the first arc ranges from 1.52 to 1.7. A reasonable ratio of the radius of the second arc to the radius of the first arc can improve the airflow guiding effect, thereby increasing the air volume and improving the air outlet efficiency. For ease of understanding, the radius of the first arc is denoted as L, and the radius of the second arc is denoted as M. In this embodiment, the ratio of the radius of the second arc to the radius of the first arc is 1.6, but it is not limited to this. In other embodiments, the ratio of the radius of the second arc to the radius of the first arc can be 1.52 or 1.7. The specific value of the ratio of the radius of the second arc to the radius of the first arc is not limited.

[0036] Furthermore, the central angle of the first arc ranges from 70 degrees to 83 degrees. A reasonable central angle of the first arc ensures that the arc has sufficient length to guide airflow, thereby improving the airflow effect and reducing noise. For ease of understanding, the central angle of the first arc is denoted as A. In this embodiment, the central angle of the first arc is 76 degrees, but it is not limited to this. In other embodiments, the central angle of the first arc can be 70 degrees or 83 degrees; the size of the central angle of the first arc is not specifically limited.

[0037] It is worth noting that the functional relationship of the fitting curve formed by the cross-section of flange side 122 is as follows:

[0038]

[0039] Where x is in millimeters, the x-axis is the direction along the line connecting the two ends of the arc of the blade 120 and extending from the blade 120 to the fixing ring 110, the y-axis is perpendicular to the x-axis and extends from the concave flange side 121 to the convex flange side 122, and the origin is the endpoint of the arc of the blade 120 away from the fixing ring 110. For ease of understanding, the origin is represented as point o.

[0040] Specifically, as shown in the above functional relationship, the cross-section of the flange side 122 includes a first curved segment, a second curved segment, a third curved segment, and a straight segment connected in sequence. The first curved segment is positioned away from the fixed ring 110, while the straight segment is positioned close to the fixed ring 110. The entire cross-section of the flange side 122 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 de, the second curved segment as ef, the third curved segment as fg, and the straight segment as gh. During the airflow process of the centrifugal fan blade 100, the airflow on the flange side 122 flows sequentially from the first curved segment along the second and third curved segments towards the straight segment, resulting in a better velocity distribution on the surface of the flange side 122. This improves the separation and development of the air adsorption layer on the blade surface 120, effectively reduces air resistance, increases airflow efficiency, and reduces vortex noise within the volute component, making the flow field distribution more uniform.

[0041] In this embodiment, both the concave flange side 121 and the convex flange side 122 are eccentric structures. The first curved segment, the second curved segment, and a portion of the third curved segment correspond to the first circular arc, while the straight segment and another portion of the third curved segment correspond to the second circular arc. Specifically, the thickness of the blade 120 gradually increases and then gradually decreases in the x-axis direction, so that the airflow passing through the blade 120 first diffuses outward to both sides of the blade 120, and then approaches each other along the concave flange side 121 and the convex flange side 122, reducing air resistance and improving air outlet efficiency. When x = 2.5, the distance between the concave flange side 121 and the convex flange side 122 is the largest, and the thickness of the blade 120 is the largest at this time. When x = 5, the value of y is the largest, and the distance between the two ends of the arc line in the convex flange side 122 and the blade 120 is the largest.

[0042] It should be noted that the end of the blade 120 away from the fixing ring 110 is provided with a leading edge side 123. The concave edge side 121 is connected to the convex edge side 122 through the leading edge side 123. The cross-section of the leading edge side 123 is a third circular arc, which facilitates the guidance of airflow to the concave edge side 121 and the convex edge side 122 respectively, reducing air resistance and improving the air guiding effect. It can be understood that the third circular arc represents segment ad, which is the profile of the part where the concave edge side 121 and the convex edge side 122 are connected to each other at the end away from the fixing ring 110.

[0043] Furthermore, the radius of the third arc ranges from 0.5 mm to 0.7 mm. A reasonable radius of the third arc can minimize air resistance while ensuring the air guiding effect. For ease of understanding, the radius of the third arc is denoted as N. In this embodiment, the radius of the third arc is 0.6 mm, but it is not limited to this. In other embodiments, the radius of the third arc can be 0.5 mm or 0.7 mm, and the size of the radius of the third arc is not specifically limited.

[0044] Please refer to Figure 5 It is worth noting that the inlet installation angle is formed between the circle with the midpoint of the fixing ring 110 as the center and the distance between the midpoint of the fixing ring 110 and the origin as the radius, and the arc of the blade 120. That is, the inlet installation angle is formed between the circle with the midpoint of the fixing ring 110 as the center and passing through the origin and the arc of the blade 120. The inlet installation angle is formed between the tangent of the circle at the origin and the tangent of the arc of the blade 120 at the origin.

[0045] Furthermore, the inlet installation angle ranges from 60 degrees to 70 degrees. A reasonable inlet installation angle can effectively improve the static pressure ratio and isentropic efficiency of the blades 120 while ensuring the air volume. For ease of understanding, the inlet installation angle is denoted as B. In this embodiment, the inlet installation angle is 65 degrees, but it is not limited to this. In other embodiments, the inlet installation angle can be 60 degrees or 70 degrees, and the size of the inlet installation angle is not specifically limited.

[0046] Please refer to the reference. Figure 6 and Figure 7 The blade 120 includes a first blade 124 and a second blade 125. There are multiple first blades 124 and multiple second blades 125, all disposed within the fixing ring 110. Specifically, the first blades 124 and the second blades 125 have the same shape, and are staggered. This staggered arrangement effectively improves the air outlet efficiency of the centrifugal fan 100 and increases the air volume.

[0047] The fixing ring 110 includes a first fixing ring 111 and a second fixing ring 112 coaxially arranged. The first fixing ring 111 and the second fixing ring 112 have the same diameter. A plurality of first blades 124 are arranged in a ring array within the first fixing ring 111, and a plurality of second blades 125 are arranged in a ring array within the second fixing ring 112. During the process of the drive motor driving the centrifugal fan 100 to rotate, the first fixing ring 111 and the second fixing ring 112 rotate synchronously to drive the first blades 124 and the second blades 125 to move, thereby realizing the air outlet function.

[0048] Furthermore, in the circumferential direction of the fixed ring 110, the ratio of the angle at which the first blade 124 rotates to the position of an adjacent second blade 125 to the angle at which the second blade 125 rotates to the position of an adjacent first blade 124 ranges from 0.5 to 0.7. That is, on the cross-section of the centrifugal fan blade 100, a second blade 125 is located between two adjacent first blades 124, wherein the ratio of the angle between the first first blade 124 and the second blade 125 to the angle between the second blade 125 and the second first blade 124 ranges from 0.5 to 0.7. Specifically, this angle ratio is called the tooth offset ratio of the centrifugal fan blade 100. A reasonable tooth offset ratio can effectively improve the air outlet efficiency and reduce wind noise. For ease of understanding, the angle at which the first blade 124 rotates to the position of an adjacent second blade 125 is denoted as C, and the angle at which the second blade 125 rotates to the position of an adjacent first blade 124 is denoted as D.

[0049] In this embodiment, the misalignment ratio is 0.6, that is, in the circumferential direction of the fixed ring 110, the ratio of the angle at which the first blade 124 rotates to the position of the adjacent second blade 125 to the angle at which the second blade 125 rotates to the position of the adjacent first blade 124 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.

[0050] In this embodiment, the spacing between two adjacent first blades 124 is equal to the spacing between two adjacent second blades 125, that is, the number of first blades 124 in the first fixing ring 111 is equal to the number of second blades 125 in the second fixing ring 112. Specifically, the spacing between two adjacent first blades 124 ranges from 9.5 mm to 10.5 mm. A reasonable spacing between two adjacent first blades 124 can maximize the airflow while ensuring the air guiding effect. For ease of understanding, the spacing between two adjacent first blades 124 is denoted as H. In this embodiment, the spacing between two adjacent first blades 124 is 9.9 mm, but it is not limited to this. In other embodiments, the spacing between two adjacent first blades 124 can be 9.5 mm or 10.5 mm, and the size of the spacing between two adjacent first blades 124 is not specifically limited.

[0051] In the centrifugal fan blade 100 of this embodiment, blades 120 are fixedly connected within a fixing ring 110. Blades 120 have a concave flange side 121 and a convex flange side 122 oppositely arranged. The cross-section of the concave flange side 121 includes at least two arc segments with different radii connected sequentially. The cross-section of the convex flange side 122 is a fitted curve formed by four consecutively connected curves or straight lines. The functional relationship of the fitted curve is as follows:

[0052]

[0053] Where x is in millimeters, the x-axis is the direction from the blade 120 to the fixing ring 110 along the line connecting the two ends of the arc of the blade 120, and the y-axis is perpendicular to the x-axis from the concave flange side 121 to the convex flange side 122. The origin is the endpoint of the end of the arc of the blade 120 away from the fixing ring 110. Compared with the prior art, the centrifugal fan 100 provided by the present invention, due to the use of a concave flange side 121 composed of at least two arc segments and a convex flange side 122 in the shape of a fitted curve, can reduce the noise generated during the operation of the centrifugal fan 100, increase the air volume, improve the air outlet efficiency, and enhance the user experience.

[0054] Second Embodiment

[0055] 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 centrifugal fan blades 100, with the drive motor connected to the centrifugal fan blades 100. The basic structure, principle, and technical effects of the centrifugal fan blades 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.

[0056] 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 centrifugal fan blades 100 to rotate, thereby generating negative pressure and causing airflow to form an outlet airflow. This outlet airflow can pass through the heat exchanger and be blown 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.

[0057] 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.

[0058] 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 centrifugal fan blade, characterized in that, The device includes a fixing ring (110) and a blade (120). The blade (120) is fixedly connected within the fixing ring (110). The blade (120) has a concave flange side (121) and a convex flange side (122) opposite to each other. The cross-section of the concave flange side (121) includes at least two arc segments with different radii connected in sequence. The cross-section of the convex flange side (122) is a fitted curve formed by four curves or straight lines connected in sequence. The functional relationship of the fitted curve is: Where x is in millimeters, the x-axis is the direction from the blade (120) to the fixing ring (110) along the line connecting the two ends of the arc in the blade (120), the y-axis is perpendicular to the x-axis and runs from the concave side (121) to the convex side (122), and the origin is the endpoint of the end of the arc in the blade (120) away from the fixing ring (110).

2. The centrifugal fan blade according to claim 1, characterized in that, When x = 2.5, the distance between the concave flange side (121) and the convex flange side (122) is the largest, and the thickness of the blade (120) is the largest.

3. The centrifugal fan blade according to claim 1, characterized in that, When x = 5, the distance between the two ends of the arc line connecting the flange side (122) and the blade (120) is the largest.

4. The centrifugal fan blade according to claim 1, characterized in that, The cross-section of the concave edge side (121) includes a first arc and a second arc connected in sequence. The second arc is disposed between the fixing ring (110) and the first arc. The ratio of the radius of the second arc to the radius of the first arc is in the range of 1.52 to 1.

7.

5. The centrifugal fan blade according to claim 4, characterized in that, The central angle of the first arc ranges from 70 degrees to 83 degrees.

6. The centrifugal fan blade according to claim 1, characterized in that, The blade (120) has a leading edge side (123) at one end away from the fixing ring (110). The concave edge side (121) is connected to the convex edge side (122) through the leading edge side (123). The cross-section of the leading edge side (123) is a third arc, and the radius of the third arc is in the range of 0.5 mm to 0.7 mm.

7. The centrifugal fan blade according to claim 1, characterized in that, An inlet mounting angle is formed between the circle with the midpoint of the fixing ring (110) as the center and the distance between the midpoint of the fixing ring (110) and the origin as the radius, and the arc in the blade (120). The range of the inlet mounting angle is 60 degrees to 70 degrees.

8. The centrifugal fan blade according to claim 1, characterized in that, The blade (120) includes a first blade (124) and a second blade (125), and there are multiple first blades (124) and multiple second blades (125). The fixing ring (110) includes a first fixing ring (111) and a second fixing ring (112) arranged coaxially. Multiple first blades (124) are arranged in a ring array within the first fixing ring (111), and multiple second blades (125) are arranged in a ring array within the second fixing ring (112). The first blades (124) and the second blades (125) are staggered. In the circumferential direction of the fixing ring (110), the ratio of the angle at which the first blade (124) rotates to the position of an adjacent second blade (125) to the angle at which the second blade (125) rotates to the position of an adjacent first blade (124) is in the range of 0.5 to 0.

7.

9. The centrifugal fan blade according to claim 8, characterized in that, The distance between two adjacent first blades (124) is equal to the distance between two adjacent second blades (125), and the distance between two adjacent first blades (124) ranges from 9.5 mm to 10.5 mm.

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

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