CN105756962A - Low-noise lampblack fan - Google Patents

Abstract

The invention provides a low-noise oil fume blower, which comprises a centrifugal fan with one end closed, and the closed end of the centrifugal fan is axially connected to the driving motor; the outer periphery of the centrifugal fan is surrounded by a fan casing; the fan casing has a The axial air inlet of the cavity, and a tangential air outlet; a sound-absorbing block made of sound-absorbing material is arranged between each adjacent fan blade of the centrifugal fan, and each of the sound-absorbing blocks is arranged together to be in the center of the centrifugal fan. There is a circular array of sound-absorbing blocks inside the fan blade array, and there are gaps between the sound-absorbing blocks; the diameter of the axial air inlet of the fan housing is smaller than the inner diameter of the circular array of sound-absorbing blocks, so that the axial air inlet The airflow entering the inside of the fan casing must pass through the circular array of sound-absorbing blocks before reaching the tangential air outlet. During the working process, the range fume fan can effectively prevent and absorb the noise in the air duct, so as to prevent it from entering the room, thereby forming a low-noise cooking environment.

Description

Low noise range fume fan

technical field

The invention relates to the field of electromechanical equipment, in particular to a range fume blower.

Background technique

Range hoods are widely used, especially for modern home kitchens, range hoods are basic kitchen appliances; and in the actual use of range hoods, they will generate relatively loud noises, and the larger components of this noise come from the air ducts. In the current structure of range hoods, the noise in the air duct passes directly through the fan of the fan and is introduced into the room through the fume suction port, causing greater noise pollution.

Contents of the invention

In view of the above problems, the purpose of the present invention is to provide a low-noise cooking fume fan, which can effectively prevent and absorb the noise in the air duct during operation, so as to prevent it from entering the room, thereby forming a low-noise cooking environment.

The technical solution adopted by the present invention to solve the technical problem is: the low-noise oil fume blower includes a centrifugal fan with one end closed, and the closed end of the centrifugal fan is axially connected to the driving motor; the outer periphery of the centrifugal fan is surrounded by a fan casing; The fan casing has an axial air inlet facing the inner cavity of the centrifugal fan, and a tangential air outlet; a sound-absorbing block made of sound-absorbing material is respectively provided between adjacent blades of the centrifugal fan, and each The sound-absorbing blocks are arranged together to form a circular array of sound-absorbing blocks inside the fan blade array of the centrifugal fan, and there are gaps between the sound-absorbing blocks; the diameter of the axial air inlet of the fan casing is smaller than the inner side of the circular array of sound-absorbing blocks Diameter, so that the airflow entering the inside of the fan casing from the axial air inlet must pass through the circular array of sound-absorbing blocks before reaching the tangential air outlet.

As preferably, the tangent line of the inner end of the blade of the centrifugal fan is along the radial direction of the centrifugal fan, so that the noise flowing from the outside of the centrifugal fan through between adjacent blades flows into the centrifugal fan along the radial direction, so as to face The sound-absorbing block promotes noise-absorbing efficiency.

Preferably, the sound-absorbing block is in the shape of a tile facing the fan blade of the centrifugal fan; on the one hand, it can cover the noise flowing from between the fan blades to the sound-absorbing block; airflow resistance.

Preferably, the circular array of sound-absorbing blocks has two layers, and the gap between adjacent sound-absorbing blocks in the circular array of sound-absorbing blocks in the outer layer is right against a sound-absorbing block in the circular array of sound-absorbing blocks in the inner layer; The sound waves diffracted by the gaps in the circular array are further absorbed by the circular array of inner sound-absorbing blocks.

Preferably, the orientation of the blades of the centrifugal fan satisfies the following requirements: when the centrifugal fan exhausts air outwards, the linear velocity of the centrifugal fan at the tangential air outlet is toward the air outlet; since the airflow noise in the air duct is usually low frequency Noise, according to this preferred solution, when the bass noise is transmitted to the circular array of sound-absorbing blocks in the centrifugal fan, it will form a relative motion with the circular array of sound-absorbing blocks near the tangential air outlet, so that the sound-absorbing block and the noise have a huge relative speed, thus forming The Doppler effect makes the noise shift from low frequency to high frequency relative to the sound-absorbing block, thus significantly improving the noise absorption efficiency of the sound-absorbing block.

The beneficial effect of the present invention is that: during the use of the low-noise oil fume blower, the noise flowing into the fan casing from the air duct first passes through the blades of the centrifugal fan, and since the sound waves do not turn with the air flow, no matter the speed of the centrifugal fan Regardless of the state of the rotation angle, the noise flowing out from the fan blades must impact on the sound-absorbing blocks and be absorbed by the sound-absorbing blocks; thereby reducing the noise of the fan to a large extent.

Description of drawings

Fig. 1 is a structural schematic diagram of Embodiment 1 of the low-noise lampblack blower.

Fig. 2 is a schematic structural diagram of Embodiment 2 of the low-noise oil fume blower.

detailed description

Below in conjunction with accompanying drawing and embodiment the present invention is further described:

Embodiment one:

In the first embodiment shown in Figure 1, the low-noise oil fume blower includes a centrifugal fan 1 with one end closed, and the closed end of the centrifugal fan 1 is axially connected to the drive motor (at the rear of the figure, not shown); The outer periphery of the fan 1 is surrounded by a fan casing 2; the fan casing 2 has an axial air inlet 20 towards the inner cavity of the centrifugal fan, and a tangential air outlet 21; each adjacent fan blade 11 of the centrifugal fan 1 A sound-absorbing block 3 made of sound-absorbing material is arranged between them, and each of the sound-absorbing blocks 3 is arranged together to form a circular array of sound-absorbing blocks on the inner side of the fan blade array of the centrifugal fan, and there is a gap between each sound-absorbing block 3; The caliber of the axial air inlet 20 of the fan casing 2 is smaller than the inner diameter of the sound-absorbing block circumferential array, so that the airflow entering the fan casing 2 from the axial air inlet 20 must pass through the sound-absorbing block circular array to reach the Describe the tangential air outlet 21. It should be pointed out that in order to avoid friction, there must be a gap between the side of the centrifugal fan 1 and the fan casing 2, but since the gap is small, the influence on the overall flow direction of the airflow and noise is negligible.

In the above-mentioned low-noise oil fume fan, the tangent line of the inner end of the fan blade 11 of the centrifugal fan 1 is along the radial direction of the centrifugal fan 1, so that the noise flowing between the adjacent fan blades from the outside of the centrifugal fan 1 is along the radial direction. Flow into the centrifugal fan 1 to face the sound-absorbing block 3 to promote the noise-absorbing efficiency.

In addition, the orientation of the blades 11 of the centrifugal fan 1 satisfies the following requirements: when the centrifugal fan 1 exhausts air outwards, the linear velocity of the centrifugal fan 1 at the tangential air outlet 21 is toward the air outlet, as shown in FIG. 1 In the first embodiment, when the centrifugal fan 1 exhausts air, the turning direction is as shown by the curved arrow in Figure 1; since the airflow noise in the air duct is usually low-frequency noise, according to this preferred solution, the low-frequency noise is transmitted to the circumference of the sound-absorbing block in the centrifugal fan 1 When arraying, it forms a relative movement with the circular array of sound-absorbing blocks near the tangential air outlet 21, so that the sound-absorbing block 3 and the noise have a huge relative speed, thereby forming the Doppler effect, making the noise move from low frequency to high frequency relative to the sound-absorbing block. frequency, thereby significantly improving the absorption efficiency of the sound-absorbing block 3 for noise.

During the use of the above-mentioned low-noise oil fume fan, the noise flowing into the fan casing 2 from the air duct first passes through the blades 11 of the centrifugal fan 1, and since the sound waves do not turn with the air flow, no matter the speed and rotation angle of the centrifugal fan 1 However, the noise flowing out from the fan blades 11 must impact on the sound-absorbing blocks 3 and be absorbed by the sound-absorbing blocks 3; thereby reducing the noise of the fan to a large extent.

Embodiment two:

For the second embodiment shown in Figure 2, the difference from the first embodiment is that the sound-absorbing block 3 is in the shape of a tile facing the fan blade 11 of the centrifugal fan 1; The noise of the sound-absorbing block 3 , on the other hand, can reduce the resistance to the airflow flowing from the cavity of the centrifugal fan to the fan blade 11 . The circular array of sound-absorbing blocks has two layers, and the gap between adjacent sound-absorbing blocks 3 of the circular array of sound-absorbing blocks in the outer layer is facing one of the circular arrays of sound-absorbing blocks in the inner layer; thus, the circular array of sound-absorbing blocks in the outer layer The sound waves diffracted by the gaps are further absorbed by the circular array of inner sound-absorbing blocks.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications and equivalent replacements made within the spirit and principles of the present invention should be included within the protection scope of the present invention .

Claims (5)

1. a low noise lampblack fan, including the centrifugal fan (1) that one end is closed, the blind end axle of described centrifugal fan (1) is connected to drive motor；Described centrifugal fan (1) periphery surrounds blower housing (2)；It is characterized in that: described blower housing (2) has an air inlet through hollow shaft mouth (20) towards described centrifugal fan (1) inner chamber and a tangential air outlet (21)；One piece of sound-absorbing block (3) being made up of sound-absorbing material it is respectively equipped with between each adjacent flabellum (11) of described centrifugal fan (1), each described sound-absorbing block (3) Common arrangements becomes to be in the sound-absorbing block circumference array inside the flabellum array of centrifugal fan (1), and leaves space between each sound-absorbing block (3)；The bore of the air inlet through hollow shaft mouth (20) of described blower housing (2), less than the inside diameter of described sound-absorbing block circumference array, makes to enter the internal air-flow of blower housing (2) from described air inlet through hollow shaft mouth (20) and must get to described tangential air outlet (21) after sound-absorbing block circumference array.

2. low noise lampblack fan according to claim 1, it is characterized in that: the inner tangent line of the flabellum (11) of described centrifugal fan (1) is along the radial direction of centrifugal fan (1), so that the noise flowed through between each adjacent flabellum (11) from centrifugal fan (1) outside flows in centrifugal fan (1) along radial direction, with just to described sound-absorbing block (3).

3. low noise lampblack fan according to claim 1, it is characterised in that: described sound-absorbing block (3) is in the shoe of the flabellum (11) towards centrifugal fan.

4. the low noise lampblack fan according to claim 1 or 3, it is characterised in that: described sound-absorbing block circumference array has two-layer, and the space between the adjacent sound-absorbing block of outer layer sound-absorbing block circumference array is right against one piece of sound-absorbing block in internal layer sound-absorbing block circumference array；So that being absorbed by internal layer sound-absorbing block circumference array further from diffraction out sound wave between the space of outer layer sound-absorbing block circumference array.

5. low noise lampblack fan as claimed in any of claims 1 to 3, it is characterized in that: the flabellum (11) of described centrifugal fan (1) is towards meeting following requirement: this centrifugal fan (1) is when outside air draft, and centrifugal fan (1) is in the linear velocity at described tangential air outlet (21) place towards air outlet (21).