Range hood

Abstract

The invention discloses a range hood, which comprises: a box body, the front side of which is provided with a smoke 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, part of the volute is arranged in the fan frame, and part of the volute is arranged in the box body; a chamfer is formed in the circumferential direction of the volute, and the molded line of the volute is a straight line at the chamfer; the corner cut is partially located in the fan frame and partially located in the box body, and an air outlet of the volute and the corner cut are located on the left side and the right side of the vertical plane where the axis of the impeller is located respectively.

Description

Technical Field

[0001] The invention relates to an oil fume purification device, in particular to a range hood. Background Art

[0002] Range hoods have become one of the indispensable kitchen appliances in modern families. Usually, range hoods include top suction type and side suction type. Side suction range hoods use the principle of vortex wind pressure to absorb most of the oil smoke close to the stove in an arc form, which can reduce the adverse effects on human health. In addition, the power source is close to the stove, which basically does not reduce the suction effect of the power source.

[0003] At present, most range hoods use multi-blade centrifugal fans as the fan system. Due to the shape of the fan, a motor, an impeller and a volute are required to achieve the oil fume suction effect. Traditional volutes are mostly in the shape of snail shells to ensure a smooth and streamlined exterior. For side-suction range hoods, the size of the volute in the fan determines the shape of the range hood to a certain extent. Generally speaking, for side-suction range hoods, the fan can be arranged in a bottom-mounted (the volute is entirely located in the box below the fan frame), a middle-mounted (part of the volute is in the fan frame, and part of it is in the box) and an upper-mounted (the volute is entirely located in the fan frame). When the middle-mounted method is adopted, as disclosed in Chinese patents with application numbers 201821797797.2, 201920309724.2 and 201920739000.1.

[0004] The size of the fan frame of the range hood determines whether it can be installed in the cabinet. When the width of the fan frame is certain, it determines the width of the volute of the center-mounted fan. For the range hood, in order to pursue the oil fume extraction effect, the larger the diameter of the volute and the impeller, the greater the air volume, so when the width of the fan frame is the largest, try to enlarge the volute. For the range hood with the fan in the center, since the widest part of the volute is 420mm, the width of the fan frame exceeds 400mm, and the size of the cabinet is 400-450mm, which makes it difficult for the fan frame to match the cabinet and cannot meet the installation and replacement requirements; in addition, the volute will affect the inclination of the cabinet, resulting in a large height and thickness of the whole machine, affecting the exquisiteness of the appearance, and also occupying too much cooking space. The volute is installed in the whole machine with a large inclination of 45° to 60°, which will affect the oil fume extraction effect. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a range hood in view of the deficiencies in the above-mentioned prior art, so as to improve the installation adaptability and ensure the range hood extraction effect.

[0006] The technical solution adopted by the present invention to solve the above technical problems is: a range hood, comprising:

[0007] The box body has a smoke inlet formed on the front side thereof;

[0008] A fan frame connected to the box; and

[0009] A fan, comprising a volute and an impeller arranged in the volute, wherein the volute comprises an upward air outlet, and the volute is partially arranged in a fan frame and partially arranged in a box; characterized in that:

[0010] A cut angle is formed on the circumference of the volute, and the profile of the volute is a straight line at the cut angle; the cut angle is partially located in the fan frame and partially located in the box body, and the air outlet and the cut angle of the volute are respectively located on the left and right sides of the vertical plane where the axis of the impeller is located.

[0011] By forming a cut angle on the volute, the width of the volute can be reduced so that it can adapt to the existing fan rack without widening the fan rack, thereby achieving product installation and replacement, so that the installation position is higher than that of a fan without a cut angle, and the noise source is farther away from the human ear; increasing the cut angle of the volute can increase the inclination angle of the whole machine and reduce the height, and can achieve a better straight exhaust effect. Because the smoke inlet is closer to the volute, the airflow path is shorter, and the airflow loss along the way is less, thereby improving the oil fume absorption effect, or reducing the height and thickness of the whole machine and reducing the volume of the whole machine.

[0012] Preferably, the acute angle between the cutting angle and the horizontal direction is a, and the value range of a is 50-65°. If a is too small, beyond this range, the strength of the narrowest part of the volute is affected, resulting in insufficient strength. The volute profile is analyzed. If a is too large, the cutting thickness is too large, which will affect the performance of the fan.

[0013] To avoid interference between the fan and the fan frame, on the same vertical section, the intersection of the cut angle of the volute and the top of the box body is P, the horizontal distance between the intersection and the adjacent side wall of the fan frame is t2, and the value range of t2 is 5 to 8 mm. The vertical section is a plane extending in the left and right direction of the range hood and is perpendicular to the above-mentioned vertical plane.

[0014] The air volume loss caused by the volute cutting angle is not compensated, and the smoke inlet is offset in the direction away from the cutting angle, so that the center of the smoke inlet in the left and right direction and the cutting angle are located on opposite sides of the center of the box in the left and right direction.

[0015] Further, on the same vertical section, the vertical section is a plane extending in the left-right direction of the range hood and is perpendicular to the vertical plane, the acute angle between the cut angle and the horizontal direction is a, there is a point q on the cut angle, the angle between the line from point q to the center of the base circle and the vertical direction is a, the angle between the line from point q to the center of the base circle and the line from the starting point of the cut angle to the center of the base circle is b, the air volume loss volume of the cut angle of the volute is V, and V=Ln), where Ln is the total thickness of the volute, r is the radius of the base circle of the volute profile, and t is the height from the center of the arc of the base circle between the starting point and the end point of the cut angle to the vertical line segment of the cut angle;

[0016] The smoke inlet is rectangular, the length direction of the smoke inlet is the left and right direction of the range hood, the height of the smoke inlet is d, and the offset distance of the smoke inlet is f, f=θ*Ln(2∠bπr / 360-sinb(rt)) / (S2*d), wherein θ is a constant, the value range of θ is 1.05 to 1.2, and S2 is the vertical distance from the center of the air inlet of the volute to the plane where the smoke inlet is located on the same vertical plane.

[0017] In order to filter the oil smoke, a filter is arranged at the smoke inlet.

[0018] To facilitate driving the impeller, the fan also includes a motor for driving the impeller to rotate.

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

[0020] Compared with the prior art, the advantages of the present invention are: by forming a volute with a cut angle, the width of the volute can be reduced so as to adapt to the existing fan frame without widening the fan frame, thereby achieving product installation and replacement, so that the installation position is higher than that of the fan without a cut angle, and the noise source is farther away from the human ear; by increasing the cut angle of the volute, the inclination angle of the whole machine can be increased and the height can be reduced, so that the straight exhaust effect can be achieved better. Because the smoke inlet is closer to the volute, the airflow path is shorter, and the airflow loss along the way is less, thereby improving the oil fume absorption effect, or reducing the height and thickness of the whole machine and reducing the volume of the whole machine. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a schematic diagram of a range hood according to an embodiment of the present invention;

[0022] Figure 2 is a cross-sectional view of a range hood according to an embodiment of the present invention;

[0023] Figure 3 is a schematic diagram of a fan of a range hood according to an embodiment of the present invention;

[0024] Figure 4It is a schematic diagram of the installation of the fan of the range hood in the first extreme position according to an embodiment of the present invention;

[0025] Figure 5 It is a schematic diagram of the installation of the fan of the range hood in the second extreme position according to an embodiment of the present invention;

[0026] Figure 6 Schematic diagram of installation comparison between the fan of the range hood according to the embodiment of the present invention and the fan of the prior art (front cross-sectional view);

[0027] Figure 7 A schematic diagram comparing the installation of a fan of a range hood according to an embodiment of the present invention and a fan of the prior art (side cross-sectional view, with the inclination angle unchanged);

[0028] Figure 8 A schematic diagram comparing the installation of a fan of a range hood according to an embodiment of the present invention and a fan of the prior art (side cross-sectional view with an increased inclination angle);

[0029] Fig. 9 It is a front view of the hidden part of the range hood according to the embodiment of the present invention. DETAILED DESCRIPTION

[0030] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals represent the same or similar elements or elements having the same or similar functions.

[0031] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or position relationship based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Since the embodiments disclosed in the present invention can be set in different directions, these terms indicating directions are only for illustration and should not be regarded as limitations. For example, "up" and "down" are not necessarily limited to directions opposite to or consistent with the direction of gravity. In addition, the features defined as "first" and "second" may explicitly or implicitly include one or more of such features.

[0032] See also Figure 1 to Figure 3 A range hood is a side-suction range hood, which includes a box body 1, a fan frame 2 connected to the box body 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 12 is arranged at the smoke inlet 11. The fan 3 is a centrifugal fan, which includes a volute 31, an impeller 32 arranged in the volute 31, and a motor 33 for driving the impeller 32 to rotate. The volute 31 is partially arranged in the fan frame 2 and partially arranged 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, there is an angle between the axis X of the impeller 32 and the horizontal direction, and the fan 3 gradually tilts forward from bottom to top.

[0034] See also Figure 3 to Figure 5 , a cut angle 311 is formed on the circumference of the volute 31. The cut angle 311 refers to cutting off the original spiral shape of the volute 31 profile, and changing the profile of the volute 31 at this location into a straight line (the profile of the conventional volute 31 here is a spiral line). The existence of the cut angle 311 makes the width of the volute 31 ( Figure 3 The left-right dimension shown in the figure is reduced to 390 mm at the cut corner 311, and can be installed in the fan frame 2 with a width of 400 mm, which can meet the requirements of range hood assembly and replacement. When the fan 3 is in the installed state, the air outlet 312 of the volute 31 faces upward, and the vertical plane where the axis X of the impeller 32 is located is S ( Figure 4 and Figure 5 The air outlet 312 and the cut corner 311 of the volute 31 are respectively located on the left and right sides of the vertical plane S, and the cut corner 311 is partially located in the fan frame 2 and partially located in the box body 1.

[0035] The acute angle between the cut angle 311 and the horizontal direction is a. The smaller a is, the larger the cut angle 311 of the volute 31 is, and the higher the height at which the volute 31 can be placed in the fan frame 2 is. The center of the base circle of the volute 31 profile (helix) is O, and the radius is r. The volute 31 has the cut angle 311, so that under the volute 31 with the same radius r, the width of the volute 31 is narrower, and the noise source (fan 3) is farther away from the human ear.

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

[0037] The parameters mentioned above satisfy the following relationship:

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

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

[0040] When the fan is placed in the middle, the volute 31 with a cut angle can shorten the height and reduce the thickness of the whole machine, usually by more than 50 mm and more than 30 mm, and the angle of the cut angle is related to the reduction in the height and thickness of the whole machine case.

[0041] For details, see Figure 6 The center of the base circle of the volute 31 of the prior art is O', and the vertical distance between it and the bottom of the wind frame 2 is K4. The Pythagorean theorem shows that: Where w is the width of wind rack 2.

[0042] The relationship between K2 and K3 is as follows: F2 = F1sina, K2 = K3-F2, so the upward displacement of the volute 31 of the present invention relative to the volute 31' of the prior art is X, that is, the height of the housing 1 is correspondingly shortened by X = K4-K2. Figure 7 , where the dotted volute 31' is the prior art, and the distance between the center of the base circle of the profile and the top of the box body 1 is K2'. The inclination angle of the box body 1 is set to Z = 30°, and the thickness of the box body 1 is less than the distance Y = XcosZ. The inclination angle refers to the angle between the front side of the box body 1 and the vertical direction. It can be seen that by setting the cut angle 311, the volute 31 is moved upward, and the volume of the box body 1 can be reduced.

[0043] See also Figure 8 In order to improve the oil fume absorption effect, the inclination angle is increased, that is, the inclination angle is increased from Z to Z1 as shown in the figure, Z1 can be 45°, and the height of the box body 1 is correspondingly shortened to X1, preferably X1 = 20mm. Similarly, the dotted volute 31' is the prior art, and the distance between the center of its profile base circle and the top of the box body 1 is K2'.

[0044] As can be seen from the above, by increasing the cut angle 311 of the volute 31, the inclination angle of the whole machine can be increased and the height can be reduced. Since the smoke inlet 11 is closer to the volute 31, the airflow path is shorter, the airflow loss along the way is less, and the oil fume absorption effect is improved. Or the height and thickness of the whole machine can be reduced to reduce the volume of the whole machine. By increasing the cut angle 311 of the volute 31, the thickness of the box body 1 is reduced by more than 30 mm, so that the distance from the smoke inlet 11 to the volute 31 is S2, and 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 from the center of the air inlet 313 of the volute 31 to the plane where the smoke inlet 11 is located on the same vertical plane S. The airflow path is shorter, the airflow loss along the way is less, and the oil fume absorption effect is improved. The volute 31 increases a cutting angle 311, so that the angle from the smoke inlet 11 to the volute 31 is M, the angle from the smoke inlet 11 to the volute 31 is N, and M>N. The angle from the smoke inlet 11 to the volute 31 means that on the same vertical plane S, a perpendicular line is drawn from the center of the air inlet 313 of the volute 31 to the plane where the smoke inlet 11 is located, and the angle between the perpendicular line and the horizontal direction, the flow channel at an angle of M is smoother than the flow channel at an angle of N, and the high-pressure area of ​​the whole machine with a large inclination angle is closer to the top, so it can achieve a better straight discharge effect.

[0045] In addition, the volute 31 increases the cut angle 311, the volume of the right side of the volute 31 is smaller, 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 smoke absorption 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 / 360-sinb(rt), assuming the total thickness of the volute is Ln, the loss volume is as follows: V=Ln*S=Ln(2∠bπr / 360-sinb(rt)).

[0046] The height dimension of the smoke inlet 11 is d, and the smoke inlet 11 is d away from the cutting angle 311 ( Fig. 9 The leftward offset distance 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 box 1 in the left-right direction. The air inlet area offset to the left is: S 偏移进风面积 =d*f. Considering the conversion of air intake efficiency and the loss of air volume along the way, the constant θ is set to a value range of 1.05 to 1.2, S2*S 偏移进风面积 =θ*V, then S2*d*f=θ*Ln(2∠bπr / 360-sinb(rt)), from which we can get the value of f, f=θ*Ln(2∠bπr / 360-sinb(rt)) / (S2*d).

[0047] When the size of the smoke inlet 11 remains unchanged, by adjusting the position of the smoke inlet 11 , the air intake efficiency is not affected by the cut angle 311 of the volute 31 , and the oil fume absorbing effect is not reduced.

Claims

1. A range hood, comprising: The box body (1) has a smoke inlet (11) formed on the front side thereof; A fan frame (2) is connected to the box body (1); as well as A fan (3) comprises a volute (31) and an impeller (32) arranged in the volute (31), wherein the volute (31) comprises an upward air outlet (312), and wherein part of the volute (31) is arranged in a fan frame (2) and part of the volute (31) is arranged in a housing (1); the characteristics are: A cut corner (311) is formed in the circumferential direction of the volute (31), and the profile of the volute (31) is a straight line at the cut corner (311); the cut corner (311) is partially located in the fan frame (2) and partially located in the box body (1); the air outlet (312) and the cut corner (311) of the volute (31) are respectively located on the left and right sides of a vertical plane (S) where an axis (X) of the impeller (32) is located.

2. The range hood according to claim 1, characterized in that: The acute angle between the cutting angle (311) and the horizontal direction is a, and the value range of a is 50-65°.

3. The range hood according to claim 1, characterized in that: On the same vertical section, the intersection point of the cut angle (311) of the volute (31) and the top of the housing (1) is P, the horizontal distance between the intersection point (P) and the adjacent side wall of the fan frame (2) is t2, and the value range of t2 is 5 to 8 mm, and the 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).

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

5. The range hood according to claim 4, characterized in that: On the same vertical section, the vertical section is a plane extending in the left-right direction of the range hood and is perpendicular to the vertical plane (S), the acute angle between the cut angle (311) and the horizontal direction is a, there is a point q on the cut angle (311), the angle between the line connecting point q to the center of the base circle (O) and the vertical direction is a, the angle between the line connecting point q to the center of the base circle (O) and the line connecting the starting point of the cut angle (311) to the center of the base circle (O) is b, the air volume loss volume of the cut angle (311) of the volute (31) is V, and V=Ln(2∠bπr / 360-sinb(rt)), 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 from the center of the arc of the base circle between the starting point and the end point of the cut angle (311) to the vertical line segment of the cut angle (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, and the offset distance of the smoke inlet (11) is f, f=θ*Ln(2∠bπr / 360-sinb(rt)) / (S2*d), wherein θ is a constant, the value range of θ is 1.05 to 1.2, and S2 is the vertical distance from the center of the air inlet (313) of the volute (31) to the plane where the smoke inlet (11) is located on the same vertical plane (S).

6. The range hood according to any one of claims 1 to 5, characterized in that: A filter screen (12) is provided at the smoke inlet (11).

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

8. The range hood according to any one of claims 1 to 5, characterized in that: The fan (3) is arranged inclined relative to the horizontal direction.

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