CN111456967B

CN111456967B - Centrifugal fan impeller

Info

Publication number: CN111456967B
Application number: CN201910048204.5A
Authority: CN
Inventors: 余旭锋
Original assignee: Ningbo Fotile Kitchen Ware Co Ltd
Current assignee: Ningbo Fotile Kitchen Ware Co Ltd
Priority date: 2019-01-18
Filing date: 2019-01-18
Publication date: 2021-05-18
Anticipated expiration: 2039-01-18
Also published as: CN111456967A

Abstract

The invention discloses a centrifugal fan impeller which comprises a front ring, a rear ring and a plurality of blades arranged between the front ring and the rear ring, wherein the impeller integrally has a central axis, each blade is provided with an inner side surface close to the central axis and an outer side surface far away from the central axis, a first contour line of the inner side surface is an arc line protruding towards the direction far away from the central axis, and a second contour line of the outer side surface is an arc line protruding towards the direction far away from the central axis X. Compared with the prior art, the invention has the advantages that: on the premise of not increasing the overall height of the impeller, the axial length of the blade is increased, the acting effect of the blade can be effectively improved, and dynamic pressure is improved; the diameter of the impeller is gradually increased from the two ends to the middle of the impeller, so that the air inlet area of the impeller can be effectively increased, and the air volume and the air pressure are improved; because the diameter increase of impeller under the prerequisite that does not increase blade quantity, can increase the clearance between the adjacent blade, reduce the resistance that the air current received from inside to the outside of blade, promote the performance once more.

Description

Centrifugal fan impeller

Technical Field

The invention relates to a power device, in particular to a centrifugal fan impeller.

Background

The range hood is the kitchen electrical apparatus that every family is indispensable, and its effect is for purifying kitchen air. At present, the household range hood basically adopts a centrifugal fan, the performance of the range hood is determined by the quality of the centrifugal fan as a core component, and the range hood is one of the core competitiveness of range hood products.

The existing centrifugal fan mainly comprises a volute, an impeller and a motor. Generally, the working principle of a centrifugal fan is as follows: an impeller with a plurality of blades rotates at a high speed in a volute and can accelerate gas entering the blades so as to increase the dynamic pressure of the gas, and the volute is used for collecting the gas coming out of the impeller and guiding the gas to an air outlet of the volute so as to convey the gas into a pipeline.

The impeller of the blades distributed equidistantly is commonly adopted in the range hood on the current market, wherein the blades are vertical in shape, the cross section of each blade is trapezoidal, the inlet angle of each blade after the blades are installed in the impeller is guaranteed to be about 90 degrees, the outlet angle of each blade is mostly 160-170 degrees, and meanwhile, the number of the blades is mostly 60. The straight blade is simple to manufacture, but has poor pneumatic performance, and when a range hood using the impeller works, air passes between the two blades after the blades do work, because the gap between the two blades is too small, the resistance is large, and the loss is large. The multi-wing centrifugal fan blades of the range hood are all arc-shaped blades (the projection on the plane of the front ring or the rear ring of the impeller is arc-shaped), the arc-shaped structures of the blades are beneficial to diversion, the resistance is reduced, the acting area is larger, the acting efficiency is high, the pneumatic performance is good, and the blade strength is high.

With the continuous improvement of quality of life, the range hood manufacturers continuously pursue large air volume and large air pressure to obtain better range hood effect, but the noise can also increase along with it. In order to obtain better user experience, the prior art generally enlarges the sizes of the air duct, the impeller, the motor and other components, thereby increasing the cost and wasting resources. Meanwhile, the size of the components is increased, so that the size of the range hood is increased inevitably, the design of a kitchen cabinet is influenced, the decoration cost is increased, and the kitchen is attractive, so that further improvement is needed.

Disclosure of Invention

The technical problem to be solved by the invention is to provide an impeller for a centrifugal fan, which can improve the acting effect and dynamic pressure without increasing the size, aiming at the problems in the prior art.

The technical scheme adopted by the invention for solving the technical problems is as follows: the utility model provides a centrifugal fan impeller, includes preceding circle, back circle and sets up a plurality of blades between preceding circle and back circle, and the impeller is whole to have the central axis, and every blade has the medial surface that is close to the central axis and keeps away from the lateral surface of central axis, its characterized in that: the first contour line of the inner side face is an arc line protruding towards the direction far away from the central axis, and the second contour line of the outer side face is an arc line protruding towards the direction far away from the central axis X.

In order to meet the design condition of the inlet angle and ensure the work doing efficiency, the two end points of the first contour line and the center of the impeller are positioned on the same plane, and the two end points of the second contour line and the center of the impeller are positioned on the same plane.

In order to avoid the phenomena of airflow disorder and vortex and cause low working efficiency of the impeller, the first contour line and the second contour line are the same circular arc lines.

In order to avoid the phenomena of airflow disorder and vortex, the impeller has low working efficiency, the radians from the two end points of the first contour line to the center of the impeller are equal, and the radians from the two end points of the second contour line to the center of the impeller are equal.

For convenience of manufacturing, the center of the first contour line is a center of the first arc line, the linear distance between the center of the first arc line and each end point of the first contour line L1 in the direction perpendicular to the central axis is D1, the center of the second contour line is a center of the second arc line, the linear distance between the center of the second arc line and each end point of the second contour line L2 in the direction perpendicular to the central axis is D2, D1 is not less than 10mm and not more than 20mm, and D2 is not less than 10mm and not more than 20 mm.

Preferably, the arc radians of the first contour line and the second contour line are both 85-95 degrees, and the diameter of the impeller is 240-260 mm.

Preferably, in order to balance the work and the manufacturing cost, the radii of the first contour line and the second contour line are both R, and the radius R ranges from R12 to R18.

According to one aspect of the invention, the projection of each blade on the plane of the front or rear ring is circular.

According to another aspect of the invention, each blade comprises a straight blade section and an arc blade section, the projection of the straight blade section is a straight line on the plane of the front ring or the rear ring, the straight blade section is close to the inner side face, the arc blade section is close to the outer side face, and the straight blade section and the arc blade section are in smooth transition.

Preferably, in order to better meet the design condition of the inlet angle, the straight blade section occupies 1/4-1/3 of the radial length of the blade.

Compared with the prior art, the invention has the advantages that: by the designed blade, the axial length of the blade is increased on the premise of not increasing the overall height of the impeller, so that the acting effect of the blade can be effectively improved, and dynamic pressure is improved; the diameter of the impeller is gradually increased from the two ends to the middle of the impeller, so that the air inlet area of the impeller can be effectively increased, and the air volume and the air pressure are improved; because the diameter increase of impeller, consequently, under the prerequisite that does not increase blade quantity, can increase the clearance between the adjacent blade, reduce the resistance that the air current received from inside to the outside of blade, promote the performance once more.

Drawings

FIG. 1 is a schematic view of an impeller according to an embodiment of the present invention;

FIG. 2 is an axial cross-sectional view of an impeller according to an embodiment of the present invention;

FIG. 3 is a schematic view of a blade of the impeller of FIG. 2;

FIG. 4 is a radial cross-sectional view of an impeller according to an embodiment of the present invention;

FIG. 5 is an enlarged schematic view of a portion I of the impeller of FIG. 4;

fig. 6 is a schematic view of a blade of an impeller according to an embodiment of the present invention.

Detailed Description

The invention is described in further detail below with reference to the accompanying examples.

Referring to fig. 1 to 6, a centrifugal fan impeller, which is mainly used for a range hood, includes a front ring 1, a rear ring 2 and a plurality of blades 3 arranged between the front ring 1 and the rear ring 2, wherein the blades 3 are arranged along the circumferential direction of the front ring 1 and the rear ring 2 at intervals.

The impeller as a whole has a central axis X, each blade 3 has an inner side surface 31 (blade inlet end) close to the central axis X and an outer side surface 32 (blade outlet end) far from the central axis X, the first contour line L1 of the inner side surface 31 is a symmetrical circular arc line protruding in a direction far from the central axis X, and the second contour line L2 of the outer side surface 32 is a symmetrical circular arc line protruding in a direction far from the central axis X. The two end points of the first contour line L1 and the center of the impeller are positioned on the same plane, and the two end points of the second contour line L2 and the center of the impeller are positioned on the same plane, so that the consistency with the inlet and outlet angles of the straight blades can be ensured, and the efficiency of the impeller can be ensured. The radians from the two end points of the first contour line L1 to the center thereof (first circular arc line center O1) are equal, and the radians from the two end points of the second contour line L2 to the center thereof (second circular arc line center O2) are equal. The linear distance between the center O1 of the first circular arc line and each end point of the first contour line L1 in the direction perpendicular to the central axis X is D1, the linear distance between the center O2 of the second circular arc line and each end point of the second contour line L2 in the direction perpendicular to the central axis X is D2, D1 is larger than or equal to 10mm and smaller than or equal to 20mm, and D2 is larger than or equal to 10mm and smaller than or equal to 20mm, so that the normal production and manufacturing process can be ensured.

Preferably, the first contour line L1 and the second contour line L2 are the same circular arcs, which is because the different circular arcs will cause the blades 3 to do different work, the local airflow flow velocity block with the long arc length and the local airflow flow velocity block with the short arc length are slow, and the phenomena of airflow turbulence and vortex occur between the two blades 3, which causes the impeller to have low working efficiency.

The arc radians of the first contour line L1 and the second contour line L2 are both 85-95 degrees, and the impeller is suitable for impellers with the diameter of 240-260 mm. The radii of the first contour line L1 and the second contour line L2 are both R, the value range of the radius R is preferably between R12 and R18 (unit is mm), too small power capability is small, and too large impeller is overweight, so that the power required by a motor for driving the impeller is overhigh, and the manufacturing cost of the range hood is high.

The projection of each blade 3 on the plane of the front ring 1 or the rear ring 2 may be a circular arc. Because the parameters of the inlet and outlet angles of the blades are in important relation with the performance (air quantity, pressure and efficiency) of the fan, the inlet angle is 90 degrees optimal, and the outlet angle is 160-170 degrees optimal. Therefore, in the present embodiment, it is preferable that a straight blade section 33 projected as a straight line is located near the inner side surface 31, and an arc blade section 34 projected as an arc is located near the outer side surface, the straight blade section 33 and the arc blade section 34 radially divide the blade 3 into two segments, the straight blade section 33 occupies 1/4 to 1/3 of the radial length of the blade 3, and the straight blade section 33 and the arc blade section 34 are smoothly transited. The inlet angle of the straight blade section 33 is α, the inlet angle of the curved blade section 34 is β, and the outlet angle of the curved blade section 34 is γ. The blade 3 with the design structure is convenient to adjust the inlet angle of the blade 3 due to the straight blade section 33, so that the design condition of the inlet angle can be better met.

Through the designed blade 3, on the premise of not increasing the overall height of the impeller, the axial length of the blade 3 is increased, the acting effect of the blade 3 can be effectively improved, and dynamic pressure is improved; the diameter of the impeller is gradually increased from the two ends to the middle of the impeller, so that the air inlet area of the impeller can be effectively increased, and the air volume and the air pressure are improved; because the diameter increase of impeller, consequently, under the prerequisite that does not increase blade 3 quantity, can increase the clearance between the adjacent blade 3, reduce the resistance that the air current received from blade 3 inside to the outside, promote the performance once more.

In the above description, the centrifugal fan is used for the range hood as an example, and of course, the centrifugal fan of the present invention may also be used in other occasions.

Claims

1. The utility model provides a centrifugal fan impeller, includes preceding circle (1), back circle (2) and sets up a plurality of blades (3) between preceding circle (1) and back circle (2), and the impeller is whole to have central axis (X), and every blade (3) have medial surface (31) that are close to central axis (X) and keep away from lateral surface (32) of central axis (X), its characterized in that: the first contour line (L1) of the inner side surface (31) is an arc line protruding in the direction away from the central axis (X), and the second contour line (L2) of the outer side surface (32) is an arc line protruding in the direction away from the central axis (X); the two end points of the first contour line (L1) and the center of the impeller are located on the same plane, and the two end points of the second contour line (L2) and the center of the impeller are located on the same plane.

2. The centrifugal fan impeller of claim 1, wherein: the first contour line (L1) and the second contour line (L2) are the same circular arc lines.

3. The centrifugal fan impeller of claim 2, wherein: the radian from two end points of the first contour line (L1) to the center of the first contour line is equal, and the radian from two end points of the second contour line (L2) to the center of the second contour line is equal.

4. The centrifugal fan impeller of claim 3, wherein: first contour line (L1) self center is first circular arc line center (O1), first circular arc line center (O1) and every endpoint of first contour line (L1), the straight line distance with central axis (X) vertical direction is D1, second contour line (L2) self center is second circular arc line center (O2), second circular arc line center (O2) and every endpoint of second contour line (L2), the straight line distance with central axis (X) vertical direction is D2, 10mm is no less than D1 and no less than 20mm, 10mm is no less than D2 and no less than 20 mm.

5. The centrifugal fan impeller of claim 2, wherein: the arc radians of the first contour line (L1) and the second contour line (L2) are both 85-95 degrees, and the diameter of the impeller is 240-260 mm.

6. The centrifugal fan impeller of claim 2, wherein: the radiuses of the first contour line (L1) and the second contour line (L2) are both R, and the value range of the radius R is between R12 and R18.

7. The centrifugal fan impeller according to any one of claims 1 to 6, wherein: the projection of each blade (3) on the plane where the front ring (1) or the rear ring (2) is located is arc-shaped.

8. The centrifugal fan impeller according to any one of claims 1 to 6, wherein: each blade (3) comprises a straight blade section (33) and an arc blade section (34), wherein the projection of the straight blade section (33) is a straight line on the plane where the front ring (1) or the rear ring (2) is located, the arc blade section (34) is in an arc shape, the straight blade section (33) is close to the inner side face (31), the arc blade section (34) is close to the outer side face (32), and the straight blade section (33) and the arc blade section (34) are in smooth transition.

9. The centrifugal fan impeller of claim 8, wherein: the straight blade section (33) occupies 1/4-1/3 of the radial length of the blade (3).