A range hood

Abstract

The application discloses an oil fume extractor, which comprises a box body, a fan frame and a fan. The front side of the box body is provided with an oil fume inlet. The fan frame is connected to the box body. The fan comprises a volute and an impeller arranged in the volute. The volute comprises an upward air outlet. The volute is partially arranged in the fan frame and partially arranged in the box body. A cutting angle is formed in the circumferential direction of the volute. The profile line of the volute is a straight line at the cutting angle. The cutting angle is partially arranged in the fan frame and partially arranged in the box body. The air outlet of the volute and the cutting angle are respectively arranged on the left and right sides of a vertical plane where the axis of the impeller is located.

Description

TECHNICAL FIELD

[0001] The present application relates to an oil fume purification device, in particular to an extractor hood. BACKGROUND

[0002] The extractor hood has become one of the indispensable kitchen household appliances in modern families. Generally, the extractor hood includes a top suction type and a side suction type. The side suction type extractor hood utilizes the vortex wind pressure principle to absorb most of the oil fume close to the cooking table in an arc form, which can reduce the adverse effects on human health, and the power source is close to the cooking table, which basically will not reduce the suction effect of the power source.

[0003] At present, the extractor hood mostly uses a multi-wing centrifugal fan as a fan system. Due to the form of the fan, a motor, an impeller and a volute are needed to achieve the effect of absorbing oil fume. The traditional volute is in the form of a snail shell, which ensures the smooth streamline type of the outside. For the side suction type extractor hood, the size of the volute in the fan determines the form of the extractor hood to some extent. Generally, the arrangement mode of the fan of the side suction type extractor hood can be down (the volute is entirely located in the box under the fan frame), middle (part of the volute is in the fan frame and part is in the box) and up (the volute is entirely located in the fan frame). When the middle mode is adopted, as disclosed in Chinese patents with application numbers 201821797797.2, 201920309724.2 and 201920739000.1, etc.

[0004] The size of the fan frame of the extractor hood determines whether it can be installed into a cabinet. When the width of the fan frame is constant, that is, the width of the volute of the middle type fan is determined. For the extractor hood, in order to pursue the effect of absorbing oil fume, the larger the diameter of the volute and the impeller, the larger the air volume. Therefore, when the width of the fan frame is the largest, the volute is enlarged as much as possible. For the extractor hood with the middle fan, due to the fact that the widest part of the volute is 420mm, the width of the fan frame exceeds 400mm, while the size of the cabinet is 400-450mm, which leads to the difficulty of matching the fan frame with the cabinet, and cannot meet the installation and replacement; in addition, the volute will affect the inclination angle of the box, leading to the large height and thickness of the whole machine, affecting the appearance delicacy, and occupying too much cooking space. The volute installed in the 45°-60° large inclination angle whole machine will affect the effect of absorbing oil fume. SUMMARY

[0005] The technical problem to be solved by the present application is to provide an extractor hood to improve the installation adaptability and ensure the effect of absorbing oil fume in view of the deficiencies of the prior art.

[0006] The technical scheme adopted by the present application to solve the above technical problem is as follows: an extractor hood, comprising:

[0007] a box, a smoke inlet is formed on the front side of the box;

[0008] a fan frame connected to the cabinet; and

[0009] a fan comprising an impeller and a volute, the volute comprising an upward air outlet, the volute being partially disposed in the fan frame and partially disposed in the cabinet; characterized in that:

[0010] a tangent corner is formed in the circumferential direction of the volute, the tangent corner being a straight line in the profile of the volute, the tangent corner being partially disposed in the fan frame and partially disposed in the cabinet, the air outlet of the volute and the tangent corner being respectively located on the left and right sides of a vertical plane in which the axis of the impeller is located;

[0011] in the same vertical section, the vertical section being a plane extending in the left-right direction of the range hood and being perpendicular to the vertical plane, the tangent corner having an acute angle a with the horizontal direction, there being a point q on the tangent corner, the tangent line from the point q to the center of the base circle having an angle a with the vertical direction, the tangent line from the point q to the center of the base circle having an angle b with the tangent line from the starting point of the tangent corner to the center of the base circle, the air volume loss volume of the tangent corner of the volute being V, and V = Ln(2∠bπr 2 / 360-tan∠b*(r-t)*(r-t)), wherein Ln is the total thickness of the volute, r is the radius of the base circle of the profile of the volute, and t is the height of the tangent line from the arc center of the base circle between the starting point and the ending point of the tangent corner to the tangent vertical line segment;

[0012] the smoke inlet is rectangular, the length direction of the smoke inlet being the left-right direction of the range hood, the height of the smoke inlet being d, and the offset distance of the smoke inlet being f, f = θ*Ln(2∠bπr 2 / 360-tan∠b*(r-t)*(r-t)) / (S2*d), wherein θ is a constant, the value of θ being in the range of 1.05-1.2, and S2 being the vertical distance from the center of the air inlet of the volute to the plane in which the smoke inlet is located in the same vertical plane.

[0013] By forming the tangent corner in the volute, the width of the volute can be reduced so as to fit the existing fan frame, without widening the fan frame, thereby achieving product installation and replacement, and making the installation position higher and the noise source farther from the human ear relative to the fan without the tangent corner. The volute with the tangent corner can make the inclination angle of the range hood larger and the height smaller, and can further achieve straight exhaust, because the position of the smoke inlet is closer to the volute, the airflow path is shorter, the airflow loss is less along the way, the oil fume extraction effect is improved, or the height and thickness of the range hood are reduced, and the volume of the range hood is reduced.

[0014] Preferably, the acute angle of the cut corner with the horizontal direction is a, and a satisfies the range of 50-65°. If a is too small, it exceeds the range, affects the strength of the narrowest part of the volute, causes insufficient strength, and analyzes the volute profile. If a is too large, the cut thickness is too large, which affects the performance of the fan.

[0015] To avoid interference between the fan and the fan frame, the intersection of the cut corner of the volute and the top of the box is P, the horizontal distance between the intersection and the adjacent side wall of the fan frame is t2, and t2 satisfies the range of 5-8mm. The vertical section is a plane extending in the left-right direction of the range hood and perpendicular to the above-mentioned vertical plane.

[0016] Without making up for the loss of air volume caused by the cut corner of the volute, the smoke inlet is offset away from the cut corner, so that the center of the smoke inlet in the left-right direction and the cut corner are located on the opposite sides of the center of the box in the left-right direction.

[0017] In order to facilitate the filtration of oil fume, a filter screen is arranged at the smoke inlet.

[0018] In order to facilitate the driving of the impeller, the fan further comprises a motor for driving the impeller to rotate.

[0019] In order to further reduce the height of the whole machine, and make the smoke inlet closer to the fan inlet, the fan is arranged obliquely relative to the horizontal direction.

[0020] Compared with the prior art, the advantages of the present application are that: by forming a cut corner in the volute, the width of the volute can be reduced to adapt to the existing fan frame, without widening the fan frame, so as to achieve product installation and replacement, so that the installation position is higher, and the noise source is farther away from the ear; the cut corner of the volute can make the inclination angle of the whole machine larger and the height smaller, and can achieve direct exhaust effect, because the position of the smoke inlet is closer to the volute, the airflow path is shorter, the airflow loss is less, the oil smoke extraction effect is improved, or the height and thickness of the whole machine are reduced, and the volume of the whole machine is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 The schematic view of the range hood of the embodiment of the present application;

[0022] Figure 2 The sectional view of the range hood of the embodiment of the present application;

[0023] Figure 3 The schematic view of the fan of the range hood of the embodiment of the present application;

[0024] Figure 4 The installation schematic view of the fan of the range hood of the embodiment of the present application at the first limit position;

[0025] Figure 5 Fig. 6 is a schematic view showing the installation of the fan of the range hood according to the embodiment of the present application in the second limit position;

[0026] Figure 6 Fig. 7 is a schematic view showing the installation of the fan of the range hood according to the embodiment of the present application and the fan of the range hood according to the prior art (front view);

[0027] Figure 7 Fig. 8 is a schematic view showing the installation of the fan of the range hood according to the embodiment of the present application and the fan of the range hood according to the prior art (side view, the inclination angle is unchanged);

[0028] Figure 8 Fig. 9 is a schematic view showing the installation of the fan of the range hood according to the embodiment of the present application and the fan of the range hood according to the prior art (side view, the inclination angle is increased);

[0029] Figure 9 Fig. 10 is a front view of the concealed part of the range hood according to the embodiment of the present application. DETAILED DESCRIPTION

[0030] Embodiments of the present application will be described in detail below, examples of which are shown in the drawings, wherein the same or similar notations represent the same or similar elements or elements having the same or similar functions.

[0031] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the purpose of facilitating the description of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, since the disclosed embodiments of the present application can be arranged in different directions, so these terms indicating the direction are only as an illustration and should not be regarded as a limitation. For example, "upper", "lower" are not necessarily limited to the direction opposite or consistent with the direction of gravity. In addition, the features defined as "first", "second" can explicitly or implicitly include one or more of the features.

[0032] Referring to Figures 1-3 A range hood, which is a side suction type range hood, comprises a cabinet 1, a fan frame 2 connected to the cabinet 1, and a fan 3.

[0033] A smoke inlet 11 is formed on the front side of the housing 1. The smoke inlet 11 is rectangular, and its length direction is the left-right direction of the range hood. A filter screen 12 is installed at the smoke inlet 11. The fan 3 is a centrifugal fan, which includes a volute 31, an impeller 32 installed in the volute 31, and a motor 33 that drives the impeller 32 to rotate. The volute 31 is partially installed in the fan frame 2 and partially installed in the housing 1. An air outlet 312 and an air inlet 313 are also formed on the volute 31. The fan 3 is inclined relative to the horizontal direction, that is, the axis X of the impeller 32 forms an angle with the horizontal direction, and the fan 3 gradually tilts forward from bottom to top.

[0034] See Figures 3-5 The volute 31 has a chamfer 311 formed in the circumferential direction. The chamfer 311 means that the original spiral shape of the volute 31 is cut off, and the volute 31 becomes a straight line at this point (the volute 31 is usually spiral at this point). The presence of the chamfer 311 increases the width of the volute 31. Figure 3 The dimensions shown (in the left-right direction) are reduced to 390mm at the chamfer 311, allowing installation within a 400mm wide fan frame 2, thus meeting the assembly and replacement requirements of the range hood. When the fan 3 is in the installed state, the air outlet 312 of the volute 31 faces upwards, and the vertical plane containing the axis X of the impeller 32 is S( Figure 4 and Figure 5 (Represented by dashed lines in the middle), the air outlet 312 and the chamfer 311 of the volute 31 are located on the left and right sides of the vertical plane S, respectively. The chamfer 311 is partially located inside the fan frame 2 and partially located inside the housing 1.

[0035] The angle between the chamfer 311 and the acute angle in the horizontal direction is α. The smaller α is, the larger the chamfer 311 of the volute 31 is, and the greater the height at which the fan frame 2 can be placed on the volute 31. The base circle of the profile (spiral) of the volute 31 has a center of O and a radius of r. The chamfer 31 of the volute 31 makes the width of the volute 31 narrower for the same radius r, and the distance between the noise source (fan 3) and the human ear is farther.

[0036] The following is described on the premise that the same vertical section is a plane extending in the left-right direction of the range hood and is perpendicular to the above-mentioned vertical plane S. There are shown an outer circle M1 corresponding to the base circle of the profile of the housing 31 and an inner circle M2 corresponding to the profile of the air inlet 313 of the volute 31. The intersection of the tangent 311 of the volute 31 and the top of the box body 1 is P, which is the installation limit position point of the volute 31. The horizontal distance between the P point and the adjacent side wall of the fan frame 2 is t2, and the value range of t2 is 5-8 mm to avoid interference between the volute 31 and the fan frame 2. K2 is the vertical distance from the center O of the base circle of the volute 31 to the top of the box body 1, and K3 is the vertical distance between the center O of the base circle of the volute 31 and the upper end (starting point) of the tangent 311. When K2 is the smallest, the volute 31 is in the highest position. t is the height of the arc center between the starting point (point close to the volute tongue of the volute 31, which is not marked in the figure, same as the prior art) and the end point (point far from the volute tongue of the volute 31) of the tangent 311 to the vertical segment of the tangent 311. There is a point q on the tangent 311, and the angle between the line connecting the point q and the center O of the base circle and the vertical direction is a, and the angle between the line connecting the point q and the center O of the base circle and the line connecting the starting point of the tangent 311 and the center O of the base circle (two lines) is b. t and a jointly affect the narrowest part of the volute 31, which refers to the smallest distance between the inner circle M2 and the tangent 311.

[0037] The above-mentioned parameters satisfy the following relationships:

[0038] K1 = r-t, cosb = K1 / r, ∠c = ∠a-∠b, K3 = rcosc = rcos(∠a-∠b).

[0039] The above formula shows that K3 affects the angle a, and the reasonable value range of the angle a is 50-65°. The state of 50° is shown in Figure 4 , and the state of 65° is shown in Figure 5 . If the value exceeds this range, the strength of the narrowest part of the volute 31 is affected, resulting in insufficient strength. The profile of the volute 31 is analyzed in Figure 4 , Figure 5 . The right side of the volute 31 shown in is a relatively low pressure area, and the cutting thickness will affect the performance of the fan.

[0040] When the fan is centrally arranged, the volute 31 with the tangent can shorten the height and reduce the thickness of the whole machine. Generally, the height of the whole machine can be shortened by more than 50 mm and the thickness can be reduced by more than 30 mm, and the angle of the tangent relates to the reduction amount of the height and thickness of the box body of the whole machine.

[0041] Figure 6 Specifically, the center of the base circle of the profile of the volute 31 in the prior art is O', and the vertical distance between O' and the bottom of the fan frame 2 is K4. It is obtained by the Pythagorean theorem that: where w is the width of the fan stand 2.

[0042] K2 and K3 are related as follows: F2 = F1sina, K2 = K3 - F2, so the distance of the volute 31 of the present application from the prior art volute 31' is X, that is, the height of the cabinet 1 is correspondingly shortened X = K4 - K2. See Figure 7 where the dashed volute 31' is the prior art, the distance between the center of the profile base circle and the top of the cabinet 1 is K2'. Assuming the inclination angle of the cabinet 1 is Z = 30°, the thickness of the cabinet 1 is less distance Y = XcosZ. The inclination angle refers to the angle between the front side of the cabinet 1 and the vertical direction. As can be seen, by providing the cut angle 311, the volute 31 is moved upward, and the volume of the cabinet 1 can be reduced.

[0043] See Figure 8 To improve the oil fume extraction effect, the inclination angle is increased, that is, the inclination angle shown in the figure is increased from Z to Z1, and Z1 is optionally 45°, and the height of the cabinet 1 is correspondingly shortened to X1, and preferably X1 = 20 mm. Similarly, where the dashed volute 31' is the prior art, the distance between the center of the profile base circle and the top of the cabinet 1 is K2'.

[0044] As can be seen from the above, the volute 31 increases the cut angle 311, the inclination angle of the whole machine is increased and the height is reduced, because the position of the smoke inlet 11 is closer to the volute 31, the airflow path is shorter, the airflow loss is less along the way, and the oil fume extraction effect is improved. Or reduce the height and thickness of the whole machine, reduce the volume of the whole machine. The volute 31 increases the cut angle 311, so that the thickness of the cabinet 1 is reduced by more than 30 mm, so that the distance from the smoke inlet 11 to the volute 31 is S2, the distance from the smoke inlet 11 to the volute 31' is S1, and S2 < S1, the distance from the smoke inlet 11 to the volute 31 refers to the vertical distance between the center of the air inlet 313 of the volute 31 and the plane on which the smoke inlet 11 is located in the same vertical plane S, the airflow path is shorter, the airflow loss is less along the way, and the oil fume extraction effect is improved. The volute 31 increases the cut angle 311, so that the angle between the smoke inlet 11 and the volute 31 is M, and the angle between the smoke inlet 11 and the volute 31 is N, and M > N, the angle between the smoke inlet 11 and the volute 31 refers to the angle between the vertical line drawn from the center of the air inlet 313 of the volute 31 to the plane on which the smoke inlet 11 is located and the horizontal direction in the same vertical plane S, the flow channel of M angle is smoother than that of N angle, and the high pressure area of the whole machine with large inclination angle is higher, so it can achieve direct exhaust effect.

[0045] In addition, the volute 31 increases the cut angle 311, the volume on the right side of the volute 31 is reduced, and the air intake on the right side will be relatively reduced. The position of the smoke inlet 11 can be adjusted to increase the air intake area on the left side to ensure the air intake of the volute 31, so as not to reduce the oil fume extraction effect. The loss area formula of the cut angle of the volute 31 is as follows: S蜗壳切角面积 =2∠bπr 2 / 360-tan∠b*(rt)*(rt), assuming the total thickness of the volute is Ln, the loss volume is as follows: V=Ln*S=Ln(2∠bπr) 2 / 360-tan∠b*(rt)*(rt)).

[0046] The height dimension of the smoke inlet 11 is d, and it extends away from the chamfer 311. Figure 9 The leftward offset distance shown is f, where f is the distance between the center of the smoke inlet 11 in the left-right direction and the center of the housing 1 in the left-right direction. The leftward offset air inlet area is: S 偏移进风面积 =d*f. Considering the conversion of intake efficiency and the air volume loss along the way, a constant θ is set, with a value ranging from 1.05 to 1.2, S2*S 偏移进风面积 =θ*V, then S2*d*f=θ*Ln(2∠bπr 2 / 360-tan∠b*(rt)*(rt)), from which we can obtain the value of f, f=θ*Ln(2∠bπr 2 / 360-tan∠b*(rt)*(rt)) / (S2*d).

[0047] With the size of the smoke inlet 11 unchanged, by adjusting the position of the smoke inlet 11, the air intake efficiency will not be affected by the chamfer 311 of the volute 31, and the oil fume extraction effect will not be reduced.

Claims

1. A range hood, comprising: a cabinet (1) having an air inlet (11) formed on a front side thereof; a fan frame (2) connected to the cabinet (1); and a fan (3) including a volute (31) and an impeller (32) disposed in the volute (31), the volute (31) including an air outlet (312) facing upward, the volute (31) being partially disposed in the fan frame (2) and partially disposed in the cabinet (1), characterized in that: a cut corner (311) is formed on a periphery of the volute (31), a profile of the volute (31) is a straight line at the cut corner (311), the cut corner (311) is partially disposed in the fan frame (2) and partially disposed in the cabinet (1), and the air outlet (312) and the cut corner (311) of the volute (31) are respectively located on left and right sides of a vertical plane (S) in which an axis (X) of the impeller (32) is located; α is in a range of 50-65°. On the same vertical section, which is a plane extending along the left-right direction of the range hood and perpendicular to the above-mentioned vertical plane (S), the acute angle between the tangent (311) and the horizontal direction is α, there is a point q on the tangent (311), the angle between the line connecting the point q and the center (O) of the base circle and the vertical direction is a, the angle between the line connecting the point q and the center (O) of the base circle and the line connecting the starting point of the tangent (311) and the center (O) of the base circle is b, the air volume loss volume of the tangent (311) of the volute (31) is V, and V = Ln(2∠bπr 2 / 360-tan∠b*(r-t)*(r-t)), wherein Ln is the total thickness of the volute (31), r is the radius of the base circle of the volute (31) profile, and t is the height of the arc center of the base circle between the starting point and the ending point of the tangent (311) to the vertical line segment of the tangent (311). The smoke inlet (11) is rectangular, the length direction of the smoke inlet (11) is the left-right direction of the range hood, the height of the smoke inlet (11) is d, the offset distance of the smoke inlet (11) is f, f = θ * Ln (2 ∠ bπr 2 / 360-tan ∠ b*(r-t)*(r-t)) / (S2*d), wherein θ is a constant, the value range of θ is 1.05-1.2, S2 is the vertical distance from the center of the air inlet (313) of the volute (31) to the plane on which the smoke inlet (11) is located in the same vertical plane (S).

2. The hood according to claim 1, characterized in that: On a same vertical section, an intersection of the cut corner (311) of the volute (31) and a top of the cabinet (1) is P, a horizontal distance between the intersection (P) and an adjacent side wall of the fan frame (2) is t2, and t2 is in a range of 5-8 mm, the vertical section is a plane extending in a left-right direction of the range hood and perpendicular to the vertical plane (S).

3. The hood according to claim 1, characterized in that: The air inlet (11) is offset in a direction away from the cut corner (311) so that a center of the air inlet (11) in the left-right direction and the cut corner (311) are located on opposite sides of a center of the cabinet (1) in the left-right direction.

4. The hood according to claim 1, characterized in that: A filter screen (12) is disposed at the air inlet (11).

5. The hood according to any one of claims 1-4, characterized in that: The fan (3) further includes a motor (33) for driving the impeller (32) to rotate.

6. The hood according to any one of claims 1-4, characterized in that: The fan (3) is disposed in a tilted manner relative to a horizontal direction.

7. The hood according to any one of claims 1-4, characterized in that: ​

Images