A noise reduction control system

Abstract

A kind of noise reduction control system, including range hood body and the noise reduction screen body of hidden setting in range hood body, range hood body is equipped with the control mechanism of controlling noise reduction screen body lifting, control mechanism is equipped with the connecting mechanism connected with noise reduction screen body;Noise reduction screen body is made of at least one screen body module;Compared with prior art, by setting hidden liftable noise reduction screen body, and noise reduction screen body is set between operator and range hood smoke inlet, in the case where not changing aerodynamic flow field, not generating secondary noise and not increasing fluid resistance, block the propagation of direct sound, isolate transmission sound, and make diffraction sound have enough attenuation, to play the role of noise reduction.

Description

Technical Field

[0001] This invention relates to the field of range hood technology, specifically to a noise reduction control system. Background Technology

[0002] Due to the general market demand for range hoods with high air volume, the noise generated by range hoods is also getting louder as the air volume gradually increases.

[0003] The noise from a range hood mainly originates from aerodynamic noise and motor noise. This noise radiates into the surrounding environment through the range hood's air inlet, duct casing, and outlet in various forms of sound propagation, including direct, reflected, and transmitted noise. To reduce the impact of noise radiated outward through the duct casing on the acoustic environment, sound absorbers / insulators are usually installed inside the duct casing. Furthermore, during actual operation, the range hood's outlet is equipped with a flue pipe, which is concealed in the ceiling. From an acoustic propagation perspective, the overall measures for the outlet and the layout of the flue provide some sound insulation. However, to ensure the range hood's air intake area and efficiency, the air inlet is usually open without any noise reduction measures, allowing the noise to radiate into the surrounding environment through direct, reflected, and transmitted noise.

[0004] Aerodynamic noise refers to noise generated in an aerodynamic flow field, including high-speed airflow, unstable airflow, and noise generated by the interaction between airflow and objects. In range hoods, aerodynamic noise includes vortex noise and rotating airflow noise. Vortex noise is radiated when pressure pulsations in turbulent airflow contain audible frequency components of sufficient intensity. Rotating airflow noise is radiated when rotating aerodynamic machinery interacts with the air, continuously generating pressure pulsations.

[0005] Motor noise refers to the noise of a motor, which mainly includes electromagnetic noise and mechanical noise. Electromagnetic noise is caused by the magnetostriction and vibration of the iron core due to the periodically changing radial electromagnetic force or unbalanced magnetic pull in the motor. Mechanical noise is generated by the friction of the motor's brushes, slip rings or commutator.

[0006] Acoustic environment quality refers to the degree of impact of external noise on the acoustic environment in which the range hood operator is located. The more obvious the impact, the worse the acoustic environment quality.

[0007] Secondary noise refers to noise that, after the installation of noise control equipment, effectively controls the original noise but causes other noise, the most common example being the generation of other aerodynamic noise (such as regenerated noise) by installing a silencer.

[0008] Insertion loss refers to the difference in sound power level before the sound wave enters the noise control equipment and after it leaves the equipment.

[0009] The existing technology's modification design of the air inlet will change the original aerodynamic flow field, which may pose a risk of causing secondary noise and ultimately affect the overall acoustic performance of the noise reduction device, while also increasing fluid resistance.

[0010] Existing technologies have modified the air inlet of range hoods, altering the dynamic flow field of the air. This results in secondary noise and increased fluid assistance, affecting the range hood's smoke extraction efficiency. In addition, the secondary noise also impacts the range hood's acoustic performance. Summary of the Invention

[0011] The present invention aims to overcome the defects in the prior art and provide a noise reduction control system that can be raised and lowered according to actual needs under the original dynamic flow field of air.

[0012] To achieve the above-mentioned objectives, the present invention adopts the following technical solution: a noise reduction control system, comprising a range hood body and a noise reduction screen hidden within the range hood body, wherein the range hood body is provided with a control mechanism for controlling the raising and lowering of the noise reduction screen, and the control mechanism is provided with a connection mechanism connected to the noise reduction screen; the noise reduction screen is composed of at least one layer of screen modules.

[0013] As a preferred embodiment of the present invention, the screen module is a frame structure, and the frame structure is arranged around the air inlet of the range hood body. The screen module includes a shell and a through hole formed on the shell, and the shell is filled with non-woven fabric and sound-absorbing cotton.

[0014] As a preferred embodiment of the present invention, the corners of the frame structure are provided with flexible sealing elements.

[0015] As a preferred embodiment of the present invention, the screen template is a panel structure, and the panel structure is disposed between the air inlet of the range hood body and the range hood panel.

[0016] As a preferred embodiment of the present invention, a sliding rail fixing component is provided between the noise reduction screen and the range hood panel for sliding connection.

[0017] As a preferred embodiment of the present invention, the noise reduction screen includes a first screen module and a second screen module connected to each other, a slide rail fixing component is also provided between the first screen module and the second screen module, and a flexible sealing component is also provided between the first screen module and the second screen module.

[0018] As a preferred embodiment of the present invention, the control mechanism includes a control board, a motor and a push-pull rod, the control board is electrically connected to the motor, and the motor drives the push-pull rod to move vertically up and down.

[0019] As a preferred embodiment of the present invention, the connecting mechanism is a lifting bracket fixedly connected to the first screen module, and the lifting bracket is fixedly connected to the push-pull rod.

[0020] As a preferred embodiment of the present invention, the first screen module and the second screen module are folded back to form a hidden first state, the first screen module and the second screen module are extended to form a single-layer structure second state, and the first screen module and the second screen module are extended and unfolded to form a double-layer structure third state.

[0021] As a preferred embodiment of the present invention, the slide rail fixing component includes a fixing component and a slider slidably connected to the fixing component, and both the first screen module and the second screen module have mounting grooves for embedding the slider.

[0022] Compared with the prior art, the beneficial effects of the present invention are:

[0023] 1. By setting up a hidden, liftable noise reduction screen between the operator and the range hood inlet, the screen blocks the propagation of direct sound, isolates transmitted sound, and attenuates diffracted sound to a sufficient extent without changing the aerodynamic flow field, generating secondary noise, or increasing fluid resistance.

[0024] 2. The height of the noise reduction screen can be adjusted to a single or double layer structure according to actual needs, so as to meet the needs of users of different heights;

[0025] 3. When the range hood is not running, the noise reduction screen rises and hides behind the range hood panel, thus concealing the noise reduction screen and making the overall structure more compact. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the structure of the present invention;

[0027] Figure 2 This is a schematic diagram of the screen module of the panel structure in use;

[0028] Figure 3 This is a schematic diagram showing the usage status of the frame-type screen module;

[0029] Figure 4 This is a structural diagram of a single-layer screen module;

[0030] Figure 5 This is a structural diagram of a dual-layer screen module;

[0031] Figure 6 This is an exploded view of the noise reduction screen and control mechanism;

[0032] Figure 7 This is a structural schematic diagram of the slide rail fixing component;

[0033] Figure 8 This is a structural diagram of the screen module;

[0034] Figure 9 This is a structural diagram of the screen module;

[0035] Reference numerals: 1. Range hood body; 2. Noise reduction screen; 21. First screen module; 22. Second screen module; 23. Housing; 24. Sound-absorbing cotton; 25. Non-woven fabric; 26. Through hole; 27. Mounting groove; 3. Control mechanism; 31. Control board; 32. Motor; 33. Push-pull rod; 4. Connecting mechanism; 5. Slide rail fixing part; 51. Fixing part; 52. Slider; 53. Slide groove; 54. Limiting part; 55. Top limiting plate; 56. Bottom limiting plate; 57. Connecting hole; 57. Sound receiving point A; Sound shadow zone B; Sound brightness zone C. Detailed Implementation

[0036] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0037] like Figures 1-9 As shown, a noise reduction control system includes a range hood body 1 and a noise reduction screen 2 hidden inside the range hood body 1. The range hood body 1 is provided with a control mechanism 3 for controlling the raising and lowering of the noise reduction screen 2. The control mechanism 3 is provided with a connection mechanism 4 connected to the noise reduction screen 2. The noise reduction screen 2 is composed of at least one screen module. The screen module includes a shell 23 and a through hole 26 formed on the shell 23. The shell 23 is filled with non-woven fabric 25 and sound-absorbing cotton 24.

[0038] The range hood body 1 has a placement groove for placing the noise reduction screen 2. The placement groove is a downward-opening groove, and the size of the placement groove is designed according to the size of the noise reduction screen 2. The size of the placement groove is slightly larger than the size of the noise reduction screen 2. When the connecting mechanism 4 is raised to a certain position under the action of the control mechanism 3, the noise reduction screen 2 is placed in the corresponding placement groove, thereby realizing the hidden setting of the noise reduction screen 2.

[0039] Example 1: The screen module is a frame structure, and the frame structure is arranged around the air inlet of the range hood body 1. When the range hood body 1 has a smoke collection chamber baffle, the frame structure screen module is connected to the smoke collection chamber baffle and the range hood panel, thereby connecting the various sides of the frame structure and ensuring that the frame structure has better stability during the lifting process.

[0040] The corners of the frame structure are equipped with flexible seals, which can be connected rubber structures to achieve zero gaps between the corners of adjacent sides of the frame structure, preventing "sound leakage through gaps"; at the same time, it ensures flexible connection between screen modules, reducing hard scratches between screens while maintaining an aesthetically pleasing appearance.

[0041] Both the smoke collection chamber baffle and the range hood panel are equipped with slide rail fixing parts 5 that connect to the frame-shaped screen module. Under the action of the slide rail fixing parts 5, the frame-shaped screen module is slidably connected on the smoke collection chamber baffle and the range hood panel, ensuring the stability of the frame-shaped screen module during the lifting process.

[0042] Example 2: The screen template is a panel structure, and the panel structure is set between the air inlet of the range hood body 1 and the range hood panel. When the range hood body 1 does not have a smoke collection chamber baffle, the screen module of the panel structure is connected to the range hood panel. At this time, the screen template is only formed on a single side of the range hood body 1, and this side is located between the operator and the air inlet of the range hood body 1.

[0043] A sliding rail fixing component 5 is provided between the noise reduction screen 2 and the range hood panel for sliding connection. Under the action of the sliding rail fixing component 5, the screen module of the panel structure is slidably connected on the range hood panel, ensuring the stability of the screen module of the panel structure during the lifting process.

[0044] The noise reduction screen 2 includes a first screen module 21 and a second screen module 22 connected to each other. A slide rail fixing component 5 is also provided between the first screen module 21 and the second screen module 22, and a flexible sealing component is also provided between the first screen module 21 and the second screen module 22. The flexible sealing component can be a connected rubber structure to achieve zero gap at the connection between the first screen module 21 and the second screen module 22, preventing "sound leakage through gaps"; at the same time, it ensures that the screen modules are flexibly connected, reducing hard scratches between the screens while ensuring an aesthetically pleasing appearance.

[0045] The control mechanism 3 includes a control board 31, a motor 32, and a push-pull rod 33. The control board 31 is electrically connected to the motor 32. The motor 32 drives the push-pull rod 33 to rise and fall vertically. A control panel electrically connected to the control board 31 can be installed on the range hood panel. The control board 31 is controlled by different function buttons on the control panel. The control board 31 is connected to the motor 32 by wires. Under the action of the control board 31, the start and stop of the motor 32 and the working time are controlled. The motor 32 drives the rise and fall of the push-pull rod 33, and the amount of descent of the push-pull rod 33 is controlled, thereby controlling the usage mode of the noise reduction screen 2.

[0046] The connecting mechanism 4 is a lifting bracket fixedly connected to the first screen module 21, and the lifting bracket is fixedly connected to the push-pull rod 33. The lifting bracket has a T-shaped structure and a threaded hole that communicates with the first screen module 21 is formed on the lifting bracket. A screw that connects to the first screen module 21 is provided in the threaded hole.

[0047] Furthermore, the T-shaped structure has a horizontally positioned support section in the middle. The support section is fixedly connected to the push-pull rod 33 by welding or screws. During the lifting and lowering process of the push-pull rod 33, the T-shaped structure as a whole is simultaneously lifted and lowered, thereby driving the first screen module 21 to unfold or retract.

[0048] The first screen module 21 and the second screen module 22 are folded back to form a hidden first state, the first screen module 21 and the second screen module 22 are extended to form a single-layer structure second state, and the first screen module 21 and the second screen module 22 are extended and unfolded to form a double-layer structure third state.

[0049] Hidden first state: When the first screen module 21 and the second screen module 22 are in the hidden state, the bottom of the first screen module 21 and the second screen module 22 are both located above the bottom of the range hood panel, thereby hiding the first screen module 21 and the second screen module 22. At this time, the extension and retraction of the push-pull rod 33 set by the control mechanism 3 is at its minimum.

[0050] Single-layer structure second state: When the first screen module 21 and the second screen module 22 are in the single-layer state, the bottom of the first screen module 21 and the second screen module 22 are both located below the bottom of the range hood panel, and the bottom of the first screen module 21 and the second screen module 22 are flush. At this time, the extension and retraction of the push-pull rod 33 set by the control mechanism 3 is at the first level.

[0051] The third state of the double-layer structure: When the first screen module 21 and the second screen module 22 are in the double-layer state, the bottom of the first screen module 21 and the bottom of the second screen module 22 are both located below the bottom of the range hood panel, and the bottom of the first screen module 21 is located below the bottom of the second screen module 22. At this time, the extension and retraction of the push-pull rod 33 set by the control mechanism 3 is at the second level.

[0052] At this time, the first screen module 21 is located below the second screen module 22, and the top of the first screen module 21 is connected to the bottom of the second screen module 22. The top of the second screen module 22 is connected to the bottom of the range hood panel. At this time, the height of the noise reduction screen 2 is the height of the first screen module 21 plus the height of the second screen module 22.

[0053] The slide rail fixing component 5 includes a fixing component 51 and a slider 52 slidably connected to the fixing component 51. The first screen module 21 and the second screen module 22 both have a slide groove 53 for embedding the slider 52.

[0054] The fixing member 51 has a limiting part 54 on both sides to restrict the degree of freedom of the slider 52. The slide groove 53 is a vertical structure. Under the action of the limiting part 54, the slider 52 is ensured to always move vertically up and down along the length direction of the slide groove 53 during the sliding process, thereby ensuring the stability of the first screen module 21 and the second screen module 22 during the lifting process.

[0055] The top of the fixing member 51 has a top limiting plate 55 that restricts the position of the slider 52, and the bottom of the fixing member 51 has a bottom limiting plate 56 that restricts the position of the slider 52. When the slider 52 moves to a certain position, the top of the slider 52 abuts against the top limiting plate 55, thereby limiting the slider 52. At this time, it is the maximum distance that the first screen module 21 and the second screen module 22 can separate. When the slider 52 moves to a certain position, the top of the slider 52 abuts against the bottom limiting plate 56, thereby limiting the slider 52. At this time, the bottoms of the first screen module 21 and the second screen module 22 are at the same horizontal height.

[0056] The slide rail fixing component 5 is between the screen unit and the range hood. The fixing component 51 is connected to the range hood, and the slider 52 is connected to the second screen module 22. The second screen module 22 is slidably connected to the range hood panel.

[0057] The slide rail fixing component 5 is between the first screen module 21 and the second screen module 22. The fixing component 51 is connected to the second screen module 22, and the slider 52 is connected to the first screen module 21. The first screen module 21 is slidably connected to the second screen module 22.

[0058] The slider 52 has a connecting hole 57 for locking the slider 52. A screw is provided in the connecting hole 57. Under the action of the screw, the slider 52 is fixedly connected to the first screen module 21 or the second screen module 22.

[0059] The first screen module 21 and the second screen module 22 have the same structure. The first screen module 21 or the second screen module 22 includes a housing 23 and sound-absorbing cotton 24 disposed in the frame-shaped housing 23. A plurality of arrayed through holes 26 are formed on the inner side of the frame-shaped housing 23. The frame-shaped housing 23 is a hollow rectangular structure. The size of the sound-absorbing cotton 24 is consistent with the hollow size of the frame-shaped housing 23. The through holes 26 serve as sound-absorbing holes of the first screen module 21. The frame-shaped housing 23 is also provided with non-woven fabric 25, which is located between the sound-absorbing cotton 24 and the through holes 26.

[0060] The second screen module 22 has a mounting groove 27 for mounting the slider 52, and the first screen module 21 also has a mounting groove 27 for mounting the slider 53. The structure of the second screen module 22 is consistent with the structure of the first screen module 21.

[0061] Under the action of the mounting slot 27, the slider 52 is embedded in the first screen module 21 or the second screen module 22, thereby making the first screen module 21 and the second screen module 22 have a smaller time interval during use and more stable lifting.

[0062] In actual use, when the noise radiated from the range hood's air inlet encounters the noise reduction screen 2, transmission and diffraction phenomena occur. Simultaneously, it absorbs some of the noise, reducing or even eliminating noise reflection. Part of the noise diffracts past the bottom of the noise reduction screen 2 and reaches the range hood operator; part penetrates the noise reduction screen 2 and reaches the receiving point A; and part is absorbed by the glass wool inside the noise reduction screen 2, converting sound energy into heat energy.

[0063] The insertion loss of the noise reduction screen 2 mainly depends on the sound energy distribution of the sound waves emitted from the range hood's air intake along the three propagation paths. The function of the noise reduction screen 2 is to block the propagation of direct sound, isolate transmitted sound, and sufficiently attenuate diffracted sound. When sound waves strike the wall of the sound-absorbing and insulating screen, diffraction occurs at the edge of the sound barrier, forming a "sound shadow zone B" behind the screen. "Sound shadow zone B" is the area requiring noise reduction; therefore, the effect of the noise reduction screen 2 is to keep the range hood operator within the "sound shadow zone B." Figure 1 As shown, it can be seen that the shorter the operator of the range hood, the higher the unfolded height of the noise reduction screen 2.

[0064] The area outside the sound shadow zone B is called the sound bright zone C. The noise reduction in the sound bright zone and the diffraction zone is very poor. As the noise reduction screen 2 moves downward, the sound bright zone C formed by the noise reduction screen 2 gradually moves downward. Thus, when the sound bright zone C is located below the operator's ear, the operator's ear is in the sound shadow zone B, which achieves the noise reduction effect.

[0065] According to preliminary theoretical calculations, when there are no other sources of noise interference, the noise impact on operators can be reduced by about 3 dB(A) when the noise reduction screen 2 is present.

[0066] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention; therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0067] Although this document uses numerous reference numerals from the accompanying drawings—such as: range hood body 1, noise reduction screen 2, first screen module 21, second screen module 22, housing 23, sound-absorbing cotton 24, non-woven fabric 25, through hole 26, mounting groove 27, control mechanism 3, control board 31, motor 32, push-pull rod 33, connecting mechanism 4, slide rail fixing part 5, fixing part 51, slider 52, slide groove 53, limiting part 54, top limiting plate 55, bottom limiting plate 56, connecting hole 57, sound receiving point A, sound shadow zone B, sound brightness zone C, etc.—the possibility of using other terms is not excluded. These terms are used merely for the convenience of describing and explaining the essence of the invention; interpreting them as any additional limitation would contradict the spirit of the invention.

Claims

1. A noise reduction control system, characterized in that, The system includes a range hood body (1) and a noise reduction screen (2) hidden inside the range hood body (1). The range hood body (1) is provided with a control mechanism (3) for controlling the raising and lowering of the noise reduction screen (2). The control mechanism (3) is provided with a connecting mechanism (4) connected to the noise reduction screen (2). The noise reduction screen (2) is composed of at least one screen module. The range hood body (1) has a placement groove for placing the noise reduction screen (2). The placement groove is a downward-opening groove. When the connecting mechanism (4) is raised to a certain position under the action of the control mechanism (3), the noise reduction screen (2) is placed in the corresponding placement groove, thereby realizing the hidden setting of the noise reduction screen (2). Correspondingly, when the connecting mechanism (4) is lowered to a certain position under the action of the control mechanism (3), the noise reduction screen (2) is set between the operator and the range hood inlet, thereby playing a noise reduction role.

2. The noise reduction control system according to claim 1, characterized in that, The screen module is a frame structure, and the frame structure is arranged around the air inlet of the range hood body (1). The screen module includes a shell (23) and a through hole (26) formed on the shell (23). The shell (23) is filled with non-woven fabric (25) and sound-absorbing cotton (24).

3. The noise reduction control system according to claim 2, characterized in that, The corners of the frame structure are equipped with flexible seals.

4. The noise reduction control system according to claim 1, characterized in that, The screen module is a panel structure, and the panel structure is located between the air inlet of the main body (1) of the range hood and the range hood panel.

5. A noise reduction control system according to claim 1, characterized in that, The noise reduction screen (2) and the range hood panel are provided with a sliding rail fixing component (5) for sliding connection.

6. A noise reduction control system according to claim 5, characterized in that, The noise reduction screen (2) includes a first screen module (21) and a second screen module (22) connected to each other. The slide rail fixing component (5) is also provided between the first screen module (21) and the second screen module (22), and a flexible sealing component is also provided between the first screen module (21) and the second screen module (22).

7. A noise reduction control system according to claim 6, characterized in that, The control mechanism (3) includes a control board (31), a motor (32) and a push-pull rod (33). The control board (31) is electrically connected to the motor (32), and the motor (32) drives the push-pull rod (33) to move vertically up and down.

8. A noise reduction control system according to claim 7, characterized in that, The connecting mechanism (4) is a lifting bracket fixedly connected to the first screen module (21), and the lifting bracket is fixedly connected to the push-pull rod (33).

9. A noise reduction control system according to claim 6, characterized in that, The first screen module (21) and the second screen module (22) are folded back to form a hidden first state, the first screen module (21) and the second screen module (22) are extended to form a single-layer structure second state, and the first screen module (21) and the second screen module (22) are extended and unfolded to form a double-layer structure third state.

10. A noise reduction control system according to claim 6, characterized in that, The slide rail fixing component (5) includes a fixing component (51) and a slider (52) slidably connected to the fixing component (51). The first screen module (21) and the second screen module (22) are both formed with mounting grooves (53) for embedding the slider (52).

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