WO2017133371A1

WO2017133371A1 - Ceiling-mounted exhaust hood

Info

Publication number: WO2017133371A1
Application number: PCT/CN2017/000134
Authority: WO
Inventors: 梁雪斐; 刘逸; 周佳杰; 王青山; 茅忠群; 诸永定; 刘戈
Original assignee: 宁波方太厨具有限公司
Priority date: 2016-02-01
Filing date: 2017-01-24
Publication date: 2017-08-10
Also published as: CN107023862B; CN107023862A

Abstract

A ceiling-mounted exhaust hood comprises a fan shroud (1), a fan (2), a fume-collecting hood (8), and a flow-guiding panel (9). The interior of the fan shroud (1) is divided, by a transverse partition (3), into a fan mounting cavity (4) and a flow-guiding cavity (5). The flow-guiding cavity (5) is located below the fan mounting cavity (4). The fan (2) is mounted inside the fan mounting cavity (4), and an air inlet (2a) thereof faces downwards and is in communication with the flow-guiding cavity (5). The air inlet (2a) of the fan (2) is disposed at a central portion of the top of the flow-guiding cavity (5). The fan (2) adopts a 3D impeller (20). The air inlet (2a) of the fan (2) faces downwards and is in communication with the flow-guiding cavity (5). A vertical section of the flow-guiding cavity (5) has a trapezoidal shape, that is, it has a short upper side and a long lower side. A flow-guiding net (6) is arranged horizontally inside the flow-guiding cavity (5). A sound-absorbing foam (7) is filled between an outer wall of the flow-guiding cavity (5) and an inner wall of the fan shroud (1). The structure and spatial layout of the exhaust hood are novel, and the fan (2) has a compact structure and a smaller size. The fan (2) has high efficiency, a high air pressure, and a large negative pressure gradient, thereby effectively preventing the escape of grease and fumes, and increasing a suction rate of the exhaust hood.

Description

Top suction type range hood

Technical field

The invention relates to a range hood, in particular to a top suction type range hood.

Background technique

The fan is an important part of the range hood. The impeller of the fan plays the role of energy conversion. The performance of the impeller directly affects the performance of the range hood. With the development of the industry, the homogenization of the fan system, which is the core component of the range hood, is becoming more and more serious, and the space for the improvement of the performance of the traditional fan is limited. At present, the fan impeller for the conventional range hood is generally formed by flat-plate stamping and forming, and the blades are generally only formed into a circular arc of uniform thickness. Since the impeller speed generally exceeds 800 RPM, the actual between the blades is Fluid separation and reflux are more pronounced. In addition, for the top suction type range hood, the air inlet of the fan generally faces the front, and the air outlet of the fan is arranged upward, that is, the air inlet of the fan and the air outlet of the fan are 90° with each other, and the fan is operated due to the impeller. The pre-spin action of the gas and the gas gradually change direction during the 90° steering process into the impeller. The simple front and rear uniform inlet and outlet angles are unfavorable for the actual functional force of the impeller. In order to improve the efficiency of the fan, although many improvements have been made in the blade structure, these improvements are limited to the binary flow technology, and the efficiency improvement of the fan is limited, and the defects of the binary impeller cannot be fundamentally overcome. Correspondingly, the existing range hood generally has the problems of low static pressure, small effective air volume, poor anti-interference ability and escape of soot. In summary, it is necessary to further improve the structure of the existing top suction range hood.

Summary of the invention

The technical problem to be solved by the present invention is to provide a top suction type range hood having a novel structure and capable of greatly increasing the static pressure value and the effective air volume in view of the above-mentioned state of the art.

The technical solution adopted by the present invention to solve the above technical problem is as follows: the top suction type range hood includes a fan cover, and a fan is installed in the fan cover, wherein the fan cover is divided into a fan inside. a mounting cavity and a rectifying cavity, the rectifying cavity is located below the fan mounting cavity, the fan adopts a three-element flow impeller, the fan is installed in the fan mounting cavity, the air inlet of the fan faces downward and the rectification is performed The cavities are connected.

In order to improve the rectifying effect, preferably, the rectifying chamber has a structure in which the upper end is small and the lower end is large, and the air inlet of the fan is disposed at a central portion of the top of the rectifying chamber.

Further preferably, the longitudinal section of the rectifying chamber has a trapezoidal structure with a short bottom and a long bottom, and the relationship between the height h1 of the rectifying chamber and the diameter D of the air inlet of the fan is D≤h1≤3D.

In order to improve the rectifying effect of the rectifying cavity, a horizontally arranged rectifying net is installed in the rectifying cavity, and the whole The relationship between the first vertical distance h2 between the flow net and the air inlet of the fan and the diameter D of the air inlet of the fan is h2 < D.

In order to reduce the working noise of the range hood, a sound-absorbing hole is opened in the cavity wall of the rectifying chamber, and sound-absorbing cotton is filled between the outer wall of the rectifying chamber and the inner wall of the fan casing.

Further preferably, the three-way flow impeller includes a rear wheel and a blade, and the bottom of the blade is mounted on the disk surface of the rear wheel and arranged in the circumferential direction of the rear wheel, and the outer side of the blade is The edge of the air outlet, the angle between the projection of the outer side on the outer circumferential surface of the rear wheel and the normal line of the outer circumference of the rear wheel ranges from -60° ≤ α ≤ 60°, the inner side of the blade The edge is the air inlet edge, and the angle β between the inner side edge projected on the outer circumferential surface of the rear wheel disc and the outer circumference of the rear wheel disc is 20°≤β≤70°, and the outer side is The angle θ formed by the line connecting the center of the bottom end and the center of the rear wheel and the line between the bottom end of the inner side and the center of the rear wheel is 10° ≤ θ ≤ 65°, and the outer side The relationship between the second vertical height h3 of the side apex relative to the rear wheel and the third vertical height h4 of the inner side apex with respect to the rear wheel is 0.2 ≤ h3 / h4 ≤ 0.8. After adopting the above structure, the ternary flow impeller has better aerodynamic performance, higher fan efficiency and wind pressure, and a larger negative pressure gradient.

Further preferably, the three-way flow impeller further includes a front cover mounted on the top of the blade, and a first arc segment that smoothly transitions from the inside to the outside is formed at a portion where the front cover intersects the meridian plane where the impeller shaft is located, The second arc segment and the straight segment, the relationship between the radius R1 of the first arc segment and the radius R2 of the second arc segment is 0.1≤R1/R2≤0.6, and the length L of the straight segment The relationship between the value and the radius R2 of the second circular arc segment is 0.1 ≤ L / R2 ≤ 0.4. Thus, the three-way flow impeller is a closed impeller, and the vanes are mounted between the rear disc and the front cover.

The fan may have various structures. Preferably, the fan includes the three-way flow impeller, the volute, the motor, the air inlet ring and the air outlet cover, and the three-way flow impeller is installed inside the volute, The output shaft of the motor is vertically downward, and the rear wheel of the three-way flow impeller is mounted on the output shaft of the motor, and the air inlet ring is installed at the air inlet of the fan and the front cover of the three-way flow impeller In cooperation with the installation, the air outlet of the fan faces upward and is offset at a side of the fan installation cavity, and the air outlet cover is mounted on the air outlet.

In order to further improve the efficiency of the fan, the distance δ between the rear wheel and the volute wall adjacent to the rear wheel is 1 mm ≤ δ ≤ 10 mm, and the front cover is sleeved outside the air inlet ring and the front cover is The vertical distance Δ between the side edge and the outer side wall of the air inlet ring is 0.5 mm ≤ Δ ≤ 5 mm.

In order to reduce the working noise of the range hood, the air outlet edge of the air outlet hood is in the shape of a lobe, or a through hole is formed in the annular wall of the air outlet of the air outlet to make the annular wall of the air outlet have a mesh structure.

Compared with the prior art, the invention has the advantages that the fan casing of the top suction range hood is internally divided into a fan installation cavity and a rectification cavity located below the fan installation cavity, and the fan installed in the fan installation cavity adopts three yuan. The impeller is flowed, and the air inlet of the fan is facing downward and communicates with the rectifying chamber. The structure and space layout of the whole range hood are relatively novel, and after the fan adopts the ternary flow impeller, the fan structure is relatively compact, the size is relatively small, and the fan efficiency The wind pressure is high, and the generated negative pressure gradient is large, which can effectively prevent the smoke from escaping, and can greatly improve the suction rate of the range hood.

DRAWINGS

1 is a schematic structural view of an embodiment of a top suction type range hood according to the present invention;

Figure 2 is a cross-sectional view showing an embodiment of a top suction range hood according to the present invention;

3 is a schematic structural view of a fan impeller according to an embodiment of the present invention;

Figure 4 is a side view of the fan impeller shown in Figure 3;

FIG. 5 is a schematic structural view showing a blade rearward tilting of an air outlet according to an embodiment of the present invention; FIG.

6 is a schematic structural view of a blade air outlet side leaning forward according to an embodiment of the present invention;

7 is a schematic view showing the projection of the air inlet side of the blade on the meridional surface of the impeller according to the embodiment of the present invention;

Figure 8 is a cross-sectional view of the fan impeller shown in Figure 3;

Figure 9 is a cross-sectional view of the fan impeller shown in Figure 3;

Figure 10 is a projection view of the blade on the meridional surface of the impeller in the embodiment of the present invention;

11 is a schematic structural view of a fan according to an embodiment of the present invention;

Figure 12 is a perspective exploded view of the fan shown in Figure 11;

Figure 13 is a cross-sectional view of the fan of Figure 11 .

detailed description

The invention will be further described in detail below with reference to the embodiments of the drawings.

As shown in Figures 1 and 2, a preferred embodiment of the top suction range hood of the present invention is shown. The top suction type range hood comprises a fan cover 1, a fan 2, a collecting hood 8, a rectifying plate 9 and the like, and the inside of the fan cover 1 is divided into a fan mounting chamber 4 and a rectifying chamber 5 through a transverse partition 3, and a rectifying chamber 5 is located below the fan installation chamber 4, the fan 2 is installed in the fan installation chamber 4, the air inlet 2a of the fan 2 faces downward and communicates with the rectification chamber 5, and the air inlet 2a of the fan 2 is disposed at the center of the top of the rectification chamber 5 For example, the air outlet of the fan 2 may be in the middle or substantially centered position, and the structure of the hood 8 and the rectifying plate 9 may be a conventional structure, and the description will not be made here.

In this embodiment, the longitudinal section of the rectifying chamber 5 has a trapezoidal structure with a short bottom and a long bottom. The relationship between the height h1 of the rectifying chamber 5 and the diameter D of the air inlet 2a of the fan 2 is D≤h1≤3D. . In addition, in order to further improve the rectifying effect of the rectifying chamber, a horizontally arranged rectifying net 6 is installed in the rectifying chamber 5, and the rectifying net 6 is provided with a filtering hole 61, the opening ratio of the rectifying net is >30%, and the rectifying net 6 The relationship between the first vertical distance h2 of the fan inlet 2a and the diameter D of the fan inlet 2a is h2 < D. In order to effectively reduce the noise during operation of the fan, a sound attenuating hole 51 is opened in the cavity wall of the rectifying chamber 5, the opening ratio is > 5%, and a sound absorbing cotton is filled between the outer wall of the rectifying chamber 5 and the inner wall of the fan casing 1 7.

As shown in FIG. 3 to FIG. 10, the impeller (installed in the fan 2) used in the embodiment of the top suction type range hood of the present invention, that is, the three-way flow impeller 20 is used. The three-way flow impeller 20 is a closed impeller including a rear wheel 21, a blade 22 and a front cover 23, and the blade 22 is mounted between the rear wheel 21 and the front cover 23, and the blade 22 has 10 to 50 pieces, specifically The bottom of the blade 22 is mounted on the disk surface of the rear wheel 21 and arranged in the circumferential direction of the rear wheel. The outer side 221 of the blade 22 is the air outlet side, and the outer side 221 is on the outer circumference of the rear wheel. The upper projection 221a and the rear wheel 21 The angle α between the circumferential normals 21a is -60° ≤ α ≤ 60°, the inner side 222 of the blade is the air inlet side, and the inner side 222 projects the rear wheel 222a on the outer circumferential surface of the rear wheel The angle β between the outer circumference normal 21a of the disk 21 is 20° ≤ β ≤ 70°, and the line L1 between the bottom end of the outer side 221 and the center of the rear wheel 21 and the bottom side of the inner side 222 are rearward and rearward. The angle L2 formed by the line L2 between the centers of the discs 21 is 10° ≤ θ ≤ 65°, and the apex P1 of the outer side 221 is opposite to the second vertical height h3 of the rear wheel 21 and the apex P2 of the inner side 222 The value of the third vertical height h4 of the rear wheel 21 is 0.2 ≤ h3 / h4 ≤ 0.8.

In addition, in this embodiment, the outer side edges 221 of the blades 22 are distributed on the outer circumferential surface of the same cylinder, the inner side edges 222 of the blades 22 are inclined obliquely inward from the top, and the bottom edges 223 of the blades 22 are located on the same plane. The top edge 224 of the blade 22 has a smooth transition structure.

The front cover 23 is mounted on the top of the blade, and a portion of the front cover 23 intersecting the meridian plane where the impeller shaft is located is formed with a first arc segment 231, a second arc segment 232, and a straight segment 233 which smoothly transition from the inside to the outside. The relationship between the radius R1 of the first arc segment 231 and the radius R2 of the second arc segment 232 is 0.1≤R1/R2≤0.6, the length L of the straight segment 233 and the radius of the second arc segment 232. The relationship between R2 is 0.1 ≤ L / R2 ≤ 0.4.

The ternary flow is defined from the dimension of the design. The ternary flow means that in the actual flow, all the flow parameters are the three-direction variable functions (x, y, z) of the spatial coordinate system. Since the actual flow of the gas is irregular, the binary flow (x, y) cannot truly reflect the actual flow trajectory of the gas, and the ternary flow can be truly reflected.

After adopting the above three-element flow impeller, the aerodynamic shape of the blade is more reasonable, the flow acceleration zone is longer, the steady flow zone is relatively longer, and the number of blades is small, which can reduce losses such as inlet impact, outlet wake de-flow, gas separation, and closer to gas. The real flow state, so the efficiency is obviously improved, the static pressure is better, the ternary flow impeller has the characteristics of compressed air. When working, a large gradient negative pressure zone is formed at the air inlet 2a of the fan to improve the anti-interference ability, thereby effectively preventing the soot. escape. After testing, the total suction pressure distribution of the top suction range hood at the fan inlet is better, and the total pressure loss is small.

As shown in FIG. 11 to FIG. 13 , the fan 2 used in the embodiment of the range hood of the present invention comprises a three-way flow impeller 20, a volute 24, a motor 25, an air inlet ring 26 and an air outlet cover 27, and a three-way flow impeller. 20 is installed inside the volute 24, the output shaft of the motor 25 is vertically downward, the rear wheel 21 of the three-way flow impeller 20 is mounted on the output shaft of the motor 25 and locked with a nut 28, and the air inlet ring 26 is mounted on the fan 2 The air inlet 2a is installed in cooperation with the front cover 23 of the three-way flow impeller 20. The air outlet of the fan 2 faces upward and is offset at the side of the fan installation chamber 4, and the air outlet cover 27 is mounted on the air outlet, and the air outlet is installed. The annular wall of the air outlet of the cover 27 is provided with a through hole 271 to make the annular wall of the air outlet have a mesh structure, thereby reducing the noise of the air outlet of the range hood. In addition, in order to make the fan more efficient, the distance δ between the rear wheel 21 and the volute wall 241 adjacent to the rear wheel is 1 mm ≤ δ ≤ 10 mm, and the front cover 23 is sleeved outside the air inlet ring 26. And the vertical distance Δ between the front side edge of the front cover 23 and the outer side wall of the air inlet ring 26 is 0.5 mm ≤ Δ ≤ 5 mm.

The above description is only a preferred embodiment of the present invention, and it should be noted that various modifications and improvements can be made to the present invention without departing from the principles of the present invention. For example, a fan can also be used. The open impeller, that is, the front cover in the closed impeller of the present embodiment is omitted, and the vent edge of the air hood can also be designed as a lobe type, which is considered to be within the protection scope of the present invention.

Claims

A top suction type range hood includes a fan cover (1), and a fan (2) is installed in the fan cover (1), characterized in that: the fan cover (1) is internally divided into a fan a mounting cavity (4) and a rectifying cavity (5), the rectifying cavity (5) being located below the fan mounting cavity (4), the fan (2) adopting a ternary flow impeller (20), the fan ( 2) Installed in the fan installation chamber (4), the air inlet (2a) of the fan (2) faces downward and communicates with the rectifying chamber (5).
The top suction type range hood according to claim 1, characterized in that: the rectifying chamber (5) has a structure in which the upper end is small and the lower end is large, and the air inlet (2a) of the fan (2) is set in the rectification. The central part of the top of the cavity (5).
The top suction range hood according to claim 1, characterized in that the longitudinal section of the rectifying chamber (5) has a trapezoidal structure with a short bottom and a long bottom, and the height h1 of the rectifying chamber (5) The relationship between the value D and the diameter D of the air inlet (2a) of the fan (2) is D ≤ h1 ≤ 3D.
The top suction range hood according to claim 1, characterized in that a horizontally arranged rectifying net (6) is installed in the rectifying chamber (5), and the rectifying net (6) and the fan air inlet The relationship between the first vertical distance h2 of (2a) and the diameter D of the fan inlet (2a) is h2 < D.
The top suction type range hood according to claim 1, characterized in that a cavity (51) is opened on the wall of the rectifying chamber (5), and the outer wall of the rectifying chamber (5) is The sound absorbing cotton (7) is filled between the inner walls of the fan cover (1).
A top suction range hood according to any one of claims 1 to 5, wherein said three-way flow impeller (20) comprises a rear wheel (21) and a blade (22), The bottom of the blade (22) is mounted on the disk surface of the rear wheel (21) and arranged in the circumferential direction of the rear wheel, and the outer side (221) of the blade (22) is the air outlet side, the outer The angle α between the projection of the side edge (221) on the outer circumferential surface of the rear wheel disc (221a) and the outer circumference normal line (21a) of the rear wheel disc (21) ranges from -60° ≤ α ≤ 60°. The inner side edge (222) of the blade (22) is the air inlet edge, and the inner side edge (222) projects on the outer circumferential surface of the rear wheel disc (222a) with the outer circumference normal of the rear wheel (21) ( The angle β between 21a) is 20° ≤ β ≤ 70°, and the line (L1) between the bottom end of the outer side (221) and the center of the rear wheel (21) and the inner side (222) The angle θ formed by the line (L2) between the bottom end and the center of the rear wheel (21) is 10° ≤ θ ≤ 65°, and the apex (P1) of the outer side (221) is relatively The second vertical height h3 of the rear wheel (21) and the third vertical height h4 of the inner side (222) vertex (P2) with respect to the rear wheel (21) Relationship 0.2≤h3 / h4≤0.8.
A top suction range hood according to claim 6, further comprising a front cover (23) mounted on the top of the blade (22), at the meridian plane where the front cover (23) and the impeller shaft are located The intersecting portions are formed with a first arc segment (231), a second arc segment (232) and a straight segment (233) which are smoothly transitioned from the inside to the outside, and the radius R1 of the first arc segment (231) The relationship between the value R2 and the radius R2 of the second circular arc segment (232) is 0.1 ≤ R1/R2 ≤ 0.6, and the length L of the straight line segment (233) and the radius R2 of the second circular arc segment (232) The relationship between the values is 0.1 ≤ L / R2 ≤ 0.4.
The top suction type range hood according to claim 7, wherein the fan (2) comprises the three-way flow impeller (20), the volute (24), the motor (25), and the air inlet. a ring (26) and an air outlet hood (27), the ternary flow impeller (20) being mounted inside the volute (24), the output shaft of the motor (25) being vertically downward, the ternary flow impeller Rear wheel of (20) (21) Mounted on the output shaft of the motor (25), the air inlet ring (26) is mounted on the air inlet (2a) of the fan (2) and cooperates with the front cover (23) of the three-way flow impeller (20) Installation, the air outlet (2a) of the fan (2) faces upward and is offset at a side of the fan installation chamber (4), and the air outlet cover (27) is mounted on the air outlet (2a) .
The top suction type range hood according to claim 8, characterized in that the distance δ between the rear wheel disc (21) and the volute wall (241) adjacent to the rear disc is 1 mm ≤ δ ≤ 10 mm The front cover (23) is sleeved outside the air inlet ring (26), and the vertical distance Δ between the front side edge of the front cover (23) and the outer side wall of the air inlet ring (26) is 0.5 mm ≤ Δ ≤5mm.
The top suction type range hood according to claim 8, wherein the air outlet edge of the air outlet cover (27) is of a lobe type or is open on the annular wall of the air outlet of the air outlet cover (27). There is a through hole (271) so that the annular wall of the air outlet is in a mesh structure.