Air outlet cover, design method of air outlet cover, fan system and extractor hood

Abstract

The present application relates to air outlet cover, air outlet cover design method, fan system and range hood, air outlet cover includes the cover body of inside hollow and the air inlet and air outlet respectively formed in the both ends of cover body, record the end face of cover body in air inlet as first end face, record the end face of cover body in air outlet as second end face, its characterized in that: the second end face is gradually inclined towards the first end face from top to bottom. The point is: through the second end face is gradually inclined towards the first end face from top to bottom, so that the air outlet cover can effectively avoid the structure of air outlet cover exceeding the range hood without changing the air outlet aperture, so that the decorative cover of range hood can easily shield the air outlet cover, improve the appearance of range hood, and the inclined outlet is more conducive to the outflow of oil smoke, improve the air outlet effect.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of oil fume purification, in particular to an air outlet cover, a design method of the air outlet cover, a fan system and a range hood. BACKGROUND

[0002] The range hood is one of the essential kitchen equipment in modern families, and the air outlet cover is an important component of the range hood, which connects the outlet of the fan system and the exhaust pipe, and guides and transports the oil fume to the public flue of the building through the air outlet cover and the exhaust pipe.

[0003] At present, the air outlet cover in the industry usually adopts a square-to-round structure, that is, the cross section of the air inlet of the air outlet cover is rectangular, the cross section of the air outlet of the air outlet cover is circular, the air inlet of the air outlet cover is connected with the outlet of the fan system, and the air outlet of the air outlet cover is connected with the exhaust pipe. In order to reduce the flow loss of the fan and improve the purification effect of the range hood, a kind of air outlet cover, check valve and range hood are disclosed in the Chinese utility model patent with the patent number ZL201920298157.5 (the authorized announcement number is CN209672407U), which comprises a cover body, the air inlet of the cover body is used for communicating with the air outlet pipe of the fan volute, the inner wall of the cover body is provided with a first inclined area, the inner wall of the air outlet pipe of the volute corresponds to the area of the volute tongue, when the cover body communicates with the air outlet pipe of the volute, the first inclined area corresponds to the second inclined area and the inclined directions are consistent.

[0004] Although the above-mentioned air outlet cover can reduce the flow loss of the fan through the first inclined area of the inner wall, but due to the following use limitations of the air outlet cover: firstly, when the air outlet cover is applied to the ultra-thin range hood, the first inclined area of the air outlet cover is easy to protrude from the main body of the range hood, so that it is difficult for the decorative cover to cover the air outlet cover, or even if the decorative cover can cover the air outlet cover, it will protrude from the ultra-thin range hood, affecting the appearance of the ultra-thin range hood; secondly, the inner wall of the above-mentioned air outlet cover is provided with a vertical area, but such vertical inner wall is not conducive to the flow of air, so the flow guiding effect of the air outlet cover is limited. Therefore, it is necessary to further improve the prior art. SUMMARY

[0005] The first technical problem to be solved by the present application is to provide an air outlet cover which can effectively avoid protruding from the range hood and facilitate the outflow of oil fume.

[0006] The second technical problem to be solved by the present application is to provide a design method of the above-mentioned air outlet cover, which improves the flow guiding effect of the air outlet cover.

[0007] The third technical problem to be solved by the present application is to provide a fan system applying the above-mentioned air outlet cover.

[0008] The fourth technical problem solved by the present application is to provide an extractor hood with the above-mentioned fan system.

[0009] The technical solution adopted by the present application to solve the first technical problem is: an air outlet cover, comprising a hollow cover body and an air inlet and an air outlet formed at two ends of the cover body respectively, the end face of the cover body where the air inlet is located is defined as a first end face, and the end face of the cover body where the air outlet is located is defined as a second end face, characterized in that: the second end face is gradually inclined toward the first end face from top to bottom.

[0010] Preferably, the cover body is formed by four wall faces, each of which is formed by extending each edge on the first end face toward the second end face.

[0011] In order to reduce the turbulence and resistance of the airflow, the inner peripheral wall of the cover body is at least partially arc-shaped.

[0012] In order to make better use of air flow, the projection of the second end face on the horizontal plane partially overlaps the projection of the first end face on the horizontal plane.

[0013] In order to facilitate the installation of the air outlet cover, the first end face is parallel to the horizontal plane.

[0014] Preferably, the cross section of the air inlet is rectangular, and the cross section of the air outlet is circular.

[0015] The technical solution adopted by the present application to solve the second technical problem is: a design method of the above-mentioned air outlet cover, characterized by comprising:

[0016] The projection of the second end face on the first end face is an ellipse, and a coordinate system is established with the center of the ellipse as the origin, the major axis of the ellipse as the X axis, and the minor axis of the ellipse as the Y axis.

[0017] The coordinates of any vertex P on the first end face in the coordinate system are obtained, and the coordinates of the point Q on the edge of the ellipse closest to the point P are calculated; finally, the coordinate value of the point Q on the second end face is calculated.

[0018] The control point coordinates closest to each vertex on the first end face on the second end face are obtained in the same way, and the control points closest to each vertex on the first end face on the second end face are connected with the corresponding vertices on the first end face, thereby forming the outer contour of each wall face on the cover body.

[0019] The above-mentioned design method makes the outer contour line segments of each wall face on the cover body the shortest, so that the inner peripheral wall of the cover body is relatively smooth, the turbulence and resistance of the airflow can be reduced, the energy loss of the air can be reduced, and the flow guiding performance can be improved.

[0020] Specifically, the specific calculation process of the coordinates of the point Q on the elliptical edge closest to the point P is as follows:

[0021] Suppose the coordinates of the point Q are (Xq, Yq), then the coordinates of the point Q satisfy equation 1: (Xq / a) 2 +(Yq / b) 2 =1; wherein a is the semi-major axis of the ellipse, a=L1 / 2, L1 is the aperture of the air outlet; b is the semi-minor axis of the ellipse, b=L1*cosθ / 2, θ is the inclination angle between the second end face and the first end face;

[0022] Since the point Q is the point on the ellipse closest to the point P, the line connecting the point P and the point Q is perpendicular to the tangent of the ellipse at the point Q, thus satisfying equation 2:

[0023] The coordinates of (Xq, Yq) can be obtained by simultaneously solving equation 1 and equation 2.

[0024] Further, the calculation formula of the coordinates (Xr, Yr) of the point Q on the second end face is as follows:

[0025] Xr=L1cosα

[0026] Yr=L1sinα

[0027] Wherein, α is the angle between the coordinate point of the point Q on the first end face and the center of the ellipse, and the calculation formula of α is as follows:

[0028] The technical solution adopted by the application to solve the third technical problem is: a fan system, comprising a volute, an impeller rotatably arranged in the volute, and an air outlet cover installed at the outlet of the volute, characterized in that: the air outlet cover adopts the air outlet cover described above.

[0029] The technical solution adopted by the application to solve the fourth technical problem is: a range hood, characterized in that: the fan system described above is applied.

[0030] Compared with the prior art, the advantages of the application are that: by gradually inclining the second end face from top to bottom towards the first end face, the air outlet cover can effectively avoid the structure of the air outlet cover exceeding the range hood without changing the aperture of the air outlet, so that the decorative cover of the range hood can easily shield the air outlet cover, and the appearance of the range hood is improved; and the inclined outlet is more conducive to the outflow of oil fumes, and the air outlet effect is improved. BRIEF DESCRIPTION OF DRAWINGS

[0031] Figure 1 Fig. 1 is a structural schematic diagram of the air outlet cover in the embodiment of the application;

[0032] Figure 2 Fig. 2 is a structural schematic diagram of the air outlet cover in the embodiment of the application; Figure 1a structural schematic view of another perspective of the fan cover;

[0033] Figure 3 a projection schematic view of the fan cover in the embodiment of the present application;

[0034] Figure 4 a mounting schematic view of the fan cover in the embodiment of the present application. DETAILED DESCRIPTION

[0035] The present application will be further described in detail below with reference to the embodiments of the drawings.

[0036] The present embodiment relates to an air outlet cover, a fan system using the air outlet cover and a range hood using the fan system. Of course, the present embodiment also relates to a design method of the air outlet cover. The fan system comprises a volute and an impeller rotatably arranged in the volute, and the air outlet cover is mounted at an outlet of the volute.

[0037] As shown in Figures 1 to 3 , the air outlet cover comprises a hollow cover body 1 and an air inlet 1a and an air outlet 1b formed at two ends of the cover body 1 respectively. The end face of the cover body 1 where the air inlet 1a is located is defined as a first end face 11, and the end face of the cover body 1 where the air outlet 1b is located is defined as a second end face 12. The shape of the first end face 11 matches the outlet of the volute, and the outlet of the second end face 12 is connected with a smoke exhaust pipe. In order to make the air outlet cover universal, the cross section of the air inlet 1a is rectangular, and the cross section of the air outlet 1b is circular.

[0038] As shown in Figure 1 , in the present embodiment, the second end face 12 is gradually inclined towards the first end face 11 from top to bottom, and as shown in Figure 4 , the second end face 12 is gradually inclined towards a wall 3 from top to bottom, so that the structure of the air outlet cover does not exceed the main body 4 of the range hood without changing the hole diameter of the joint between the air outlet cover and the smoke exhaust pipe.

[0039] As shown in Figure 2 , the cover body 1 is formed by four walls, each of which is formed by extending each edge on the first end face 11 towards the second end face 12. In addition, the inner peripheral wall of the cover body 1 is at least partially arc-shaped, so that the turbulence and resistance of the airflow can be reduced.

[0040] The projection of the second end face 12 on the horizontal plane partially overlaps the projection of the first end face 11 on the horizontal plane. In the present embodiment, in order to facilitate the installation of the first end face 11, the first end face 11 is parallel to the horizontal plane.

[0041] When the first end surface 11 and the second end surface 12 are connected by the boundary blending to form the wall surface, the outer contour line segment of each wall surface in the embodiment is recorded as the control line, the shape of each wall surface will affect the air flow condition, and when observed in the vertical air inlet view, the control line is shortest, and the air performance is good, which is mainly caused by the following reasons:

[0042] 1. When the control line is shortest, the inner wall surface shape of the cover body 1 is relatively smooth, which can reduce the turbulence and resistance of the airflow, reduce the energy loss of the air, and improve the air performance;

[0043] 2. If the control line is longer, the inner wall surface shape of the cover body 1 will change greatly, and an uneven surface is easy to be generated, which causes the airflow separation and flow instability, and affects the air performance;

[0044] 3. In addition, the longer control line will also cause the curvature change of the inner wall surface of the cover body 1 to be larger, so that the airflow needs more energy when passing through the flow guide structure, and the air resistance is increased;

[0045] Therefore, in order to make the air outlet effect of the air outlet cover best, the design method of the air outlet cover in the embodiment includes:

[0046] The projection of the second end surface on the first end surface is an ellipse, and a coordinate system is established with the center of the ellipse as the origin, the long axis of the ellipse as the X axis, and the short axis of the ellipse as the Y axis; as shown in Figure 3 ;

[0047] The coordinates of any vertex P on the first end surface in the coordinate system are obtained, and the coordinates of the point Q on the edge of the ellipse closest to the point P are calculated; and finally the coordinate value of the point Q on the second end surface is calculated.

[0048] In the same way, the control point coordinates closest to the vertices on the first end surface on the second end surface are obtained, and the control points on the second end surface closest to the vertices on the first end surface are connected with the corresponding vertices on the first end surface, thereby forming the outer contour of each wall surface on the cover body.

[0049] Since the first end surface 11 and the second end surface 12 of the air outlet cover are designed in advance, the coordinates of the first end surface in the coordinate system can be obtained in advance in the embodiment.

[0050] In addition, the specific calculation process of the point Q coordinates on the edge of the ellipse closest to the point P is as follows:

[0051] Suppose the coordinates of the point Q are (Xq, Yq), then the coordinates of the point Q satisfy equation 1: (Xq / a) 2 +(Yq / b) 2=1; where a is the semi-major axis of the ellipse, a = L1 / 2, L1 is the diameter of the air outlet; b is the semi-minor axis of the ellipse, b = L1*cosθ / 2, θ is the inclination angle between the second end face and the first end face;

[0052] Since point Q is the point on the ellipse that is closest to point P, the line connecting point P and point Q is perpendicular to the tangent to the ellipse at point Q. Therefore, equation 2 is satisfied:

[0053] Solving equations 1 and 2 simultaneously will yield the coordinates of (Xq, Yq).

[0054] The formula for calculating the coordinates (Xr, Yr) of point Q on the second end face is:

[0055] Xr=L1cosα

[0056] Yr=L1sinα

[0057] Where α is the angle between the coordinate point Q on the first end face and the line connecting the center of the ellipse, and the formula for calculating α is:

[0058] In this embodiment, as Figure 2 As shown, the four vertices on the first end face 11 are denoted as A1, A2, A3, and A4, respectively. The control point on the second end face 12 that is closest to A1 is denoted as B1, the control point on the second end face 12 that is closest to A2 is denoted as B2, the control point on the second end face 12 that is closest to A3 is denoted as B3, and the control point on the second end face 12 that is closest to A4 is denoted as B4. Then, there are four control lines in this invention, namely the first line segment composed of points A1 and B1, the second line segment composed of points A2 and B2, the third line segment composed of points A3 and B3, and the fourth line segment composed of points A4 and B4. The first line segment, the second line segment, the third line segment, and the fourth line segment are the outer contours of each wall surface of the air outlet hood.

[0059] The inner circumferential wall of the air outlet produced according to the above design method is relatively smooth, which can reduce airflow turbulence and resistance, reduce air energy loss, improve air performance, and give the air outlet good air performance.

[0060] Directional terms as used in describing the various example structural parts and elements of the application, such as "front", "back", "up", "down", "left", "right", "side", "top", "bottom", and the like are made only for the purpose of convenience in describing the illustrations and are determined based on the example orientation of the illustrations shown in the drawings. Since the embodiments disclosed herein can be positioned in different orientations, these directional terms are used only for the purpose of description and should not be construed as limiting, such as "up", "down" are not necessarily limited to the direction opposite or consistent with the direction of gravity.

Claims

1. A design method for an air outlet hood, the air outlet hood comprising an internally hollow hood body (1) and an air inlet (1a) and an air outlet (1b) respectively formed at both ends of the hood body (1), wherein the end face of the hood body (1) where the air inlet (1a) is located is designated as the first end face (11), and the end face of the hood body (1) where the air outlet (1b) is located is designated as the second end face (12), characterized in that: The second end face (12) gradually slopes towards the first end face (11) from top to bottom; The air inlet (1a) has a rectangular cross-section, and the air outlet (1b) has a circular cross-section. The design methods for the air vent cover include: The projection of the second end face onto the first end face is an ellipse. A coordinate system is established with the center of the ellipse as the origin, the major axis of the ellipse as the X-axis, and the minor axis of the ellipse as the Y-axis. Obtain the coordinates of any vertex P on the first end face in the coordinate system, and calculate the coordinates of the point Q on the edge of the ellipse that is closest to point P; finally, calculate the coordinates of point Q on the second end face. In the same manner as described above, obtain the coordinates of the control points on the second end face that are closest to each vertex on the first end face, and connect the control points on the second end face that are closest to each vertex on the first end face with the corresponding vertices on the first end face to form the outer contours of each wall surface on the cover.

2. The design method according to claim 1, characterized in that: The cover (1) is formed by four walls, each of which is formed by extending from each edge on the first end face (11) toward the second end face (12).

3. The design method according to claim 2, characterized in that: The inner peripheral wall of the cover (1) is at least partially arc-shaped.

4. The design method according to claim 2, characterized in that: The projection of the second end face (12) on the horizontal plane partially overlaps with the projection of the first end face (11) on the horizontal plane.

5. The design method according to claim 4, characterized in that: The first end face (11) is parallel to the horizontal plane.

6. The design method according to any one of claims 1 to 5, characterized in that: The specific calculation process for the coordinates of the point Q on the edge of the ellipse that is closest to point P is as follows: Assume the coordinates of point Q are (Xq, Yq), then the coordinates of point Q satisfy Equation 1: (Xq / a) 2 +(Yq / b) 2 =1; where a is the semi-major axis of the ellipse, a = L1 / 2, L1 is the diameter of the air outlet; b is the semi-minor axis of the ellipse, b = L1*cosθ / 2, θ is the inclination angle between the second end face and the first end face; Since point Q is the point on the ellipse that is closest to point P, the line connecting point P and point Q is perpendicular to the tangent to the ellipse at point Q. Therefore, equation 2 is satisfied: Solving equations 1 and 2 simultaneously will yield the coordinates of (Xq, Yq).

7. The design method according to claim 6, characterized in that: The formula for calculating the coordinates (Xr, Yr) of point Q on the second end face is: Xr=L1cosα Yr=L1sinα Where α is the angle between the coordinate point Q on the first end face and the line connecting the center of the ellipse, and the formula for calculating α is:

8. A fan system, comprising a volute, an impeller rotatably disposed within the volute, and an outlet shroud installed at the outlet of the volute, characterized in that: The fan cover is designed using the design method of the air outlet cover as described in any one of claims 1 to 5.

9. A range hood, characterized in that: The application includes the fan system as described in claim 8 above.

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