An ultra-quiet energy-saving fan for fresh air purifier

Abstract

The present invention relates to an ultra-quiet energy-saving fan for a fresh air purifier, comprising a volute, a motor, an impeller, and an air outlet, characterized in that: the upper disk above the impeller is close to the top surface of the volute; a plurality of upwind strips corresponding to the upper and lower wind blades are evenly distributed on the surface of the upper disk; the annular inner wall of the upper disk above the impeller is a raised annular protrusion, and the protrusion extends out of the circular hole of the volute. The silent fan is installed in the "silent fresh air washing air purifier" simultaneously applied by the inventor for use. The test result data proves that under the same conditions, the noise can be reduced by 6-8 decibels and the air volume can be increased by more than 10%, with good noise reduction and energy saving effects.

Description

Technical Field

[0001] The present invention belongs to the field of fan technology, and in particular relates to an ultra-quiet energy-saving fan for a fresh air purifier. Background Art

[0002] Haze weather has a great impact on human health. Haze is composed of a variety of particulate matter, among which the most harmful to health are aerosol particles with a diameter of less than 10 microns, such as mineral particles, sea salt, sulfate, nitrate, organic aerosol particles, fuel and automobile exhaust, etc. These aerosol particles can directly enter and adhere to the human respiratory tract and alveoli, especially submicron particles, which will be deposited in the upper and lower respiratory tracts and alveoli, causing acute rhinitis and acute bronchitis. For patients with chronic respiratory diseases such as bronchial asthma, chronic bronchitis, obstructive pulmonary emphysema and chronic obstructive pulmonary disease, haze weather can cause acute onset or acute aggravation of the disease.

[0003] Indoor fresh air air purifier is one of the effective facilities to prevent haze. However, the indoor fresh air air purifier products on the market generally have the disadvantages of single function and poor effect, which are mainly reflected in:

[0004] Existing indoor air purifiers, when working, only circulate indoor air in a closed manner and cannot introduce outdoor fresh air; if windows are opened for ventilation, the indoor air quality will deteriorate and the purification effect cannot be maintained. In addition, many existing fresh air purifiers simply filter solid suspended matter and cannot eliminate acidic gas pollutants in the air. In the heating season in the north, the indoor air is too dry, and the existing fresh air purifiers cannot provide humidification effect, so the human body naturally feels uncomfortable.

[0005] The inventor's utility model patent 'A household fresh air washing air purifier' (patent number 201520234508.8) has excellent fresh air purification effect, but because the product requires greater wind pressure and air volume than ordinary air purifiers during the fresh air purification process, and uses traditional ordinary centrifugal fans, the noise of the whole machine can meet the national standards, but it is still unsatisfactory.

[0006] The structure of the conventional centrifugal fan is as shown in the attached Figure 1As shown: it is mainly composed of a volute 1, an air guide ring 2, a base 3, an air outlet 4, an impeller 5, and a motor 6. The volute 1 is the cover of the fan, and there is a circular opening at the top center. The volute 1, the impeller 5, and the motor 6 are on the same central axis; the impeller 5 is composed of two upper and lower circular ring-shaped disks and a plurality of radial wind blades 11 perpendicular to the upper and lower circular ring-shaped disks. The annular surface of the upper disk 7 is a plane, and there are gaps for air circulation between the radially evenly distributed radial blades. The motor 6 is at the lower part of the central axis, and the motor 6 drives the impeller 5 to rotate in the volute 1 to centrifugally pressurize the incoming air. When the traditional centrifugal fan is working, the impeller 5 rotates driven by the motor 6, and the centrifugal force causes the air to flow from area A to area B, thereby achieving the purpose of conveying air. The opening of the volute 1 is higher than the air inlet of the impeller 5. The distance between the impeller 5 and the volute 1 is large. The air pressure in the area C near the inner side of the impeller 5 is equal to that in the area B outside the impeller 5, which is significantly higher than the air pressure inside the impeller 5. The air has a tendency to flow from C to A, which is called air reflux, resulting in a decrease in the efficiency of the fan. The function of the air guide ring 2 is to prevent the amount of air reflux to maintain a higher efficiency. However, since the pressure difference between C and A is equal to the total wind pressure of the fan, there is a large pressure difference and high flow rate of reflux air in the gap between the air guide ring 2 and the impeller 5, which causes obvious airflow sound - the applicant believes that this is the biggest noise source of ordinary centrifugal fans. Summary of the invention

[0007] The object of the present invention is to provide a fan which can significantly reduce the noise of a fresh air purifier and save energy.

[0008] The present invention is achieved in that:

[0009] The ultra-quiet energy-saving fan used in the fresh air purifier comprises a volute 1, a motor 6, an impeller 5, a base 3 and an air outlet 4; the volute 1 is the outer shell of the fan, and a circular hole 8 is provided in the middle of the top surface thereof; the impeller 5 is composed of an upper plate 7, a lower plate 10 and a plurality of wind blades 11 fixed between the upper and lower plates; the volute 1, the impeller 5 and the motor 6 are on the same central axis, and the motor 6 is located above the base 3. The motor 6 drives the impeller 5 to rotate in the volute 1. It is characterized in that: the upper plate 7 of the impeller 5 is close to the inner top surface of the volute 1; the upper surface of the upper plate 7 is evenly distributed with a plurality of windward strips 9 corresponding to the upper and lower wind blades 11; the inner edge of the upper plate 7 of the impeller 5 is an annular protrusion, and the protrusion extends out of the circular hole 8 of the volute 1.

[0010] The upper plate 7 of the impeller 5 has an inner protruding upper end that is 3-5 mm higher than the upper plane of the top plate of the volute 1 .

[0011] The upwind strip 9 on the upper plate 7 has a vertical cross section in the form of a right triangle, with a vertical right-angled side 5-8 mm high, and the inclined surface is the windward surface, which is 45±5 degrees with the upper plate 7; the gap between the top of the upwind strip 9 and the inner side of the top surface of the volute 1 is 2-3 mm.

[0012] When the ultra-quiet fan is in operation, the impeller 5 rotates driven by the motor, and the centrifugal force causes the air to flow from area A to area B to achieve the purpose of conveying air; at the same time, the air in the narrow gap between the headwind strip 9 and the top of the volute 1 also causes the airflow to flow from area C to area B under the combined action of the centrifugal force generated by the rotation of the headwind strip 9 and the force in the direction of the inclined surface of the headwind strip 9, thereby preventing the airflow from area B to area C and then to area A from flowing back. Therefore, the silent fan of the present invention removes the traditional air guide ring, but can achieve the ideal effect of not causing backflow, thereby achieving the elimination of the aerodynamic conditions that generate noise and improving the efficiency of the fan. Experiments have shown that the inventor installed the fan on the "Fresh Air Purifier Prototype" patent applied for on the same day. Compared with ordinary fans, under the same conditions, after installing the fan, the noise is reduced by 6-8 decibels and the air volume is increased by about 10%. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 Schematic diagram of the cross-section structure of a traditional centrifugal fan

[0014] Figure 2 A schematic cross-sectional view of the embodiment 1 of the present invention

[0015] Figure 3 Schematic diagram of the top view of the impeller shape and structure

[0016] Figure 4 yes Figure 3 A partial enlarged view of W - a schematic diagram showing the position, shape and composition of the upwind strip

[0017] In the figure: 1. volute, 2. air guide ring, 3. base, 4. air outlet, 5. impeller, 6. motor, 7. upper plate, 8. round hole, 9. headwind strip, 10. lower plate, 11. wind blade. DETAILED DESCRIPTION

[0018] Embodiment 1: A silent fan used in a fresh air purifier

[0019] The overall structure of the silent fan of this embodiment is as follows: Figure 2 As shown: it is composed of a volute 1, a base 3, a motor 6, an impeller 5, an air outlet 4, and a headwind strip 9.

[0020] The volute 1 is similar in shape to the volute of a conventional centrifugal fan. The inner edge of the impeller 5 is provided with a raised air inlet 6. The upper end of the raised air inlet 6 extends out of the central circular hole 8 of the volute and is 3-5 mm higher than the top surface of the volute 1. There is a gap between the raised outer wall and the central circular hole of the volute 1. The gap between the upper end of the upwind strip 7 of the upper disc of the impeller 5 and the circular hole wall at the top of the volute 1 is 2-3 mm. The motor 6 and the air outlet 4 are similar to those of conventional centrifugal fans.

[0021] Figure 3The top view effect diagram showing the shape and structure of the impeller 5 of Example 1: 7 is the upper disk of the impeller 5, 9 is the eight upwind bars fixed on the upper disk 7, and the eight upwind bars are evenly distributed radially on the impeller 5 and the upper disk 7 thereof.

[0022] Figure 4 yes Figure 3 The W partial enlarged view shows the position, shape and structure of the windward strip. The wind blade 11 is fixed between the upper disc 7 and the lower disc 10 of the impeller 5, and the windward strip 9 is fixed on the upper plane of the upper disc 7 and corresponds to the wind blade 11 below.

[0023] When the fresh air purifier equipped with the fan of the present invention is in operation, the impeller 5 rotates driven by the motor 6, and the centrifugal force causes the air to flow from area A to area B, achieving the purpose of pressurizing and conveying air. The air in the narrow gap between the impeller 5 and the volute 1 also rotates driven by the impeller 5. The air in the gap is subjected to the centrifugal force and presents a phenomenon in which the pressure on the outside is higher than that on the inside. The air pressure in area B is higher than that in area A. This pressure difference offsets the pressure difference of the air flowing back from area B to area A through the gap between the impeller 5 and the volute 1. The reverse wind strip 7 rotating with the impeller 5 prevents the radial reflux of air, eliminating the air reflux phenomenon. Therefore, the noise caused by gas reflux is effectively prevented, and the efficiency of the fan is improved.

[0024] The fan of this embodiment has the following characteristics:

[0025] The volute of the fan eliminates the guide ring 2 of the ordinary centrifugal fan;

[0026] The protrusion on the inner side of the upper plate 7 of the impeller extends out of the circular hole 8 of the volute 1 and is higher than the upper plane of the volute;

[0027] A plurality of evenly distributed upwind strips 9 fixed on the upper plate 7 are integrated with the impeller 1 and rotate with the impeller 1;

[0028] The vertical cross section of the upwind strip 9 is a right triangle, the vertical right angle side is 5-8 mm high, and the windward surface of the inclined surface is 45±5 degrees with the upper plate 7; the upwind strip 9 corresponds to the wind blade 11 below the upper plate 7 up and down;

[0029] The gap between the top inner surface of the volute 1 and the top of the upwind strip 7 on the impeller 5 is 2-3 mm.

Claims

1. An ultra-quiet energy-saving fan for a fresh air purifier, comprising a volute (1), a motor (6), an impeller (5), a base (3) and an air outlet (4); the volute (1) is the outer shell of the fan, and a circular hole (8) is provided in the middle of the top surface; the impeller (5) is composed of an upper plate (7), a lower plate (10) and a plurality of wind blades (11) fixed between the upper and lower plates; the volute (1), the impeller (5) and the motor (6) are located on the same central axis, and the motor is located above the base (3); the motor (6) drives the impeller (5) to rotate in the volute (1): the characteristics are: The upper plate (7) of the impeller (5) is close to the inner top surface of the volute (1); the upper surface of the upper plate (7) is evenly distributed with a plurality of windward strips (9) corresponding to the upper and lower wind blades (11); the inner edge of the upper plate (7) of the impeller (5) is an annular protrusion, and the protrusion extends out of the circular hole (8) of the volute (1); The upper plate (7) of the impeller (5) has an inner protruding upper end that is 3-5 mm higher than the upper plane of the top plate of the volute (1); The upwind strip (9) on the upper plate (7) has a vertical cross section in the form of a right triangle, with a vertical right-angled side of 5-8 mm in height, and an inclined surface being a windward surface, which is 45±5 degrees with the upper plate (7); and a gap between the top of the upwind strip (9) and the inner side of the top surface of the volute (1) is 2-3 mm.

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