Noise-reducing air path structure, air path device, and ventilator

Abstract

The present application relates to a noise-reducing air path structure, an air path device, and a ventilator. The noise-reducing air path structure comprises: an air path cavity; a sound-transmitting and air-blocking member, disposed in the air path cavity and configured to divide the air path cavity into an airflow part and a sound-absorbing part; and a sound-absorbing filler, disposed in the sound-absorbing part and configured to absorb sound that enters the sound-absorbing part from the airflow part through the sound-transmitting and air-blocking member. The present application achieves the effect of reducing noise while also enabling the ventilator to be miniaturized and ensuring the healthiness of the inhaled gas.

Description

Noise reduction air path structure, air path device and breathing machine TECHNICAL FIELD

[0001] The present application relates to the field of breathing machines, in particular to a noise reduction air path structure, air path device and breathing machine. BACKGROUND

[0002] As a device with artificial ventilation function, breathing machines have been widely used in the treatment of respiratory failure, sleep apnea hypopnea syndrome and other diseases caused by various reasons. When users use breathing machines to treat respiratory diseases, the breathing machine needs to inhale air from the outside to perform a series of air treatment to supply the user with breathing. In this process, there is often a lot of noise that affects the user's experience. The main sources of noise are air flow noise and fan operation noise. In order to solve the noise generated by air flow, some noise reduction related components are provided.

[0003] In related technologies, such as in the publication CN116421836A, entitled "Low-noise air source box and breathing machine", the low-noise breathing machine includes an upper cover, a turbine fan, an outlet hose, sound-absorbing cotton, and a lower cover. The upper cover and the lower cover form a sound-absorbing cavity, and the turbine fan is arranged inside the sound-absorbing cavity. The upper and lower sides of the air inlet channel are respectively provided with sound-absorbing cotton. The sound-absorbing cotton has a back glue, the inner contour of the sound-absorbing cotton is attached to the partition plate, the outer contour is attached to the inner wall surface of the labyrinth sound-absorbing cavity of the upper and lower covers, and a recess is provided on one side of the outer contour for mounting the soundproof baffle. It can effectively reduce the noise of medium and high frequencies.

[0004] In addition, CN116253293A discloses an oxygen generator with noise reduction function. The oxygen generator also has noise reduction related elements. The implementation principle of embodiment 2 is that during the filtering vibration process, the struts of the shock absorber move up and down to make the sound-absorbing plate swing up and down, thereby forming an air flow to enable the sound-absorbing plate to absorb the exhaust gas from the oxygen generator.

[0005] In the above related technologies, if noise reduction is performed by sound-absorbing cotton, particulate matter will be precipitated and absorbed by the human body during use, which will harm human health. Moreover, if noise reduction is performed by a sound-absorbing plate, a certain space size is required to achieve it, that is, the sound-absorbing plate requires a certain small hole depth and internal air layer thickness, which will make the volume of the breathing machine larger.

[0006] SUMMARY

[0007] In order to achieve noise reduction while miniaturizing the breathing machine and ensuring the health of inhaled air, the present application provides a noise reduction air path structure, air path device and breathing machine.

[0008] In a first aspect, the noise reduction air path structure provided by the present application adopts the following technical solution.

[0009] A noise reduction air path structure comprises:

[0010] An air path cavity;

[0011] A sound-permeable and gas-resistant member is arranged in the air path cavity and is used to separate the air path cavity into an air flow part and a sound absorption part;

[0012] A sound absorption filler is arranged in the sound absorption part and is used to absorb sound from the air flow part into the sound absorption part through the sound-permeable and gas-resistant member.

[0013] By adopting the above technical solution, sound in the gas can pass through the sound-permeable and gas-resistant member into the sound absorption part and then be eliminated by the sound absorption filler in the sound absorption part, but the gas will not enter the sound absorption part, so the sound absorption filler will not also precipitate particulate matter into the air flow part, so the sound absorption filler can be used while eliminating particulate matter in the gas, thereby achieving noise reduction while miniaturizing the size of the breathing machine and making the inhaled gas healthy.

[0014] Preferably, the sound-permeable and gas-resistant member is made of an elastic material and is used to make the sound-permeable and gas-resistant member vibrate by sound.

[0015] By adopting the above technical solution, the sound-permeable and gas-resistant member will vibrate when the sound passes through it, so as to consume the energy in the sound by vibration, thereby further improving the noise reduction capability.

[0016] Preferably, the sound absorption part and the air flow part are arranged to extend synchronously.

[0017] By adopting the above technical solution, the contact area between the air flow and the sound-permeable and gas-resistant member can be increased, so that more sound can enter the sound absorption part, thereby improving the noise reduction capability.

[0018] Preferably, a resonance gap exists between the sound absorption filler and the sound-permeable and gas-resistant member.

[0019] By adopting the above technical solution, because of the arrangement of the resonance gap, the sound absorption filler and the sound-permeable and gas-resistant member form a structure similar to a resonance cavity, so as to weaken the noise.

[0020] In a second aspect, the present application provides an air path device, which adopts the following technical solution.

[0021] An air path device comprises a noise reduction air path structure, a shell, and a fan, the shell is provided for the noise reduction air path structure, the shell is also provided with a power cavity, the power cavity is arranged in communication with the air path cavity; the fan is arranged in the power cavity.

[0022] By adopting the technical scheme, the noise reduction air path structure is applied to the air path device, so that the air path device can have a smaller size while achieving noise reduction, and the gas delivered by the air path device does not contain particulate matter, so that the gas inhaled by people is healthy, and in addition, the power cavity is arranged so that the gas does not immediately enter the fan after leaving the air path cavity, but first accumulates in the power cavity and then enters the fan, so that the flow rate does not change significantly, thereby reducing the generation of additional noise.

[0023] Preferably, the air path cavity is arranged in a serpentine bending manner.

[0024] Compared with the straight-line extension arrangement of the air path cavity, this design can make the structure of the air path device more compact, without making the span of the air path device in a certain direction too large, thereby helping to miniaturize the breathing machine. Secondly, because the airflow is slower at the bending part than at the straight-line part, more sound can pass through the sound-permeable and sound-absorbing part and enter the sound-absorbing part at the bending part, thereby helping to improve the noise reduction capability.

[0025] Preferably, the air path cavity is provided with a flow guide plate at the bending part, and the flow guide plate is arranged in a bending manner corresponding to the bending part of the air path cavity.

[0026] Because the collision between the airflow and the inner wall of the airflow part is stronger at the bending part than at the straight-line part, the arrangement of the flow guide plate can increase the contact area between the airflow and the sound-permeable and sound-absorbing part while reducing the generation of new noise, thereby helping to improve the noise reduction capability.

[0027] Preferably, the airflow passes through the air path cavity and the power cavity in sequence, the power cavity is located above the air path cavity, and the air path cavity extends in a bending manner in the horizontal direction.

[0028] By adopting the technical scheme, the gas is saturated in the air path cavity but has a slow flow rate, and the gas is not saturated in the power cavity but has a fast flow rate, so that the pressure difference at the communication part between the air path cavity and the power cavity is not too large, thereby reducing the noise at the communication part between the air path cavity and the power cavity. In addition, the shell can be in a flip cover structure at the power cavity, so as to facilitate maintenance of the fan.

[0029] Preferably, the shell is divided into an upper cover and a lower bottom plate, the upper cover has the power cavity, the lower side of the upper cover is provided with an airflow groove, the groove opening of the airflow groove is covered by the sound-permeable and sound-absorbing part to form the airflow part, the lower bottom plate is located on the side of the sound-permeable and sound-absorbing part away from the upper cover, the lower bottom plate and the sound-permeable and sound-absorbing part form the sound-absorbing part, and the lower bottom plate and the upper cover clamp and fix the sound-permeable and sound-absorbing part.

[0030] By adopting the technical scheme, the lower bottom plate and the upper cover body sandwich the sound-transmitting and gas-blocking piece to divide the gas path cavity into the airflow part and the sound absorption part, that is, the upper cover body, the sound-transmitting and gas-blocking piece, and the lower bottom plate are arranged in sequence from top to bottom, so that the sound-transmitting and gas-blocking piece directly separates the upper cover body and the lower bottom plate in terms of structural distribution, and the separation sealing between the airflow part and the sound absorption part is better. On the other hand, the sound-transmitting and gas-blocking piece is sandwiched and fixed by the upper cover body and the lower bottom plate, so that the sound-transmitting and gas-blocking piece is compressed and deformed, better connection tightness is achieved between the sound-transmitting and gas-blocking piece and the upper cover body and the lower bottom plate, and the sound-transmitting and gas-blocking piece, the upper cover body, and the lower bottom plate are more convenient to assemble and disassemble. Moreover, the vibration generated in the working process of the fan is first weakened by the sound-transmitting and gas-blocking piece and then transmitted to the lower bottom plate, so that the vibration amplitude of the gas path device is reduced, and the noise generated by the gas path device is further reduced.

[0031] In a third aspect, the ventilator provided in the present application adopts the technical scheme as follows.

[0032] A ventilator includes a gas path device.

[0033] By adopting the technical scheme, the noise is reduced, the ventilator is miniaturized, and the inhaled gas is healthy.

[0034] In summary, the present application includes at least one of the following beneficial technical effects:

[0035] 1. For the noise reduction gas path structure, the sound in the gas can pass through the sound-transmitting and gas-blocking piece into the sound absorption part and be eliminated by the sound absorption filler in the sound absorption part, but the gas will not enter the sound absorption part, and therefore the sound absorption filler will not precipitate particulate matter into the airflow part. Therefore, the sound absorption filler can be used while eliminating the particulate matter in the gas, so that the ventilator is miniaturized and the inhaled gas is healthy while the noise is reduced.

[0036] 2. For the gas path device, the lower bottom plate and the upper cover body sandwich the sound-transmitting and gas-blocking piece to divide the gas path cavity into the airflow part and the sound absorption part, so that the sound-transmitting and gas-blocking piece is more convenient to assemble and disassemble, and the separation sealing between the airflow part and the sound absorption part is improved. On the other hand, the vibration generated in the working process of the fan is first weakened by the sound-transmitting and gas-blocking piece and then transmitted to the lower bottom plate, so that the vibration amplitude of the gas path device is reduced, and the noise generated by the gas path device is further reduced. BRIEF DESCRIPTION OF DRAWINGS

[0037] FIG. 1 is a structural schematic diagram of a noise reduction gas path structure in an embodiment of the present application.

[0038] FIG. 2 is a sectional view of a gas path device in an embodiment of the present application.

[0039] Fig. 3 is a schematic diagram of a connection mode among the upper cover, the lower bottom plate and the sound-permeable and gas-blocking piece in the embodiment of the present application.

[0040] Reference numeral 1, gas path cavity; 11, air flow part; 12, sound absorption part; 2, sound-permeable and gas-blocking piece; 3, sound absorption filler; 4, shell; 41, upper cover; 42, lower bottom plate; 5, fan; 6, power cavity; 7, flow guide plate; 8, air flow groove. DETAILED DESCRIPTION

[0041] The present application will be further described in detail below in combination with Figs. 1-3.

[0042] The embodiment of the present application discloses a noise reduction gas path structure.

[0043] Referring to Fig. 1, the noise reduction gas path structure comprises a gas path cavity 1, a sound-permeable and gas-blocking piece 2 and a sound absorption filler 3. The gas path cavity 1 is configured as a channel with at least two communication ports. The sound-permeable and gas-blocking piece 2 is arranged in the gas path cavity 1, and the sound-permeable and gas-blocking piece 2 divides the gas path cavity 1 into an air flow part 11 and a sound absorption part 12. The gas cannot flow between the air flow part 11 and the sound absorption part 12, but the sound can communicate between the air flow part 11 and the sound absorption part 12. The sound absorption filler 3 is arranged in the sound absorption part 12, and the material of the sound absorption filler 3 includes but is not limited to sound-absorbing cotton, polyurethane foam plastic, wave peak sponge, foaming glue and fiber material. The sound absorption filler 3 can absorb the sound entering the sound absorption part 12 from the air flow part 11 through the sound-permeable and gas-blocking piece 2.

[0044] Referring to Fig. 1, the working principle is as follows. The sound in the gas can pass through the sound-permeable and gas-blocking piece 2 to enter the sound absorption part 12, and then be eliminated by the sound absorption filler 3 in the sound absorption part 12. However, the gas will not enter the sound absorption part 12, so the sound absorption filler 3 will not also release particulate matters into the air flow part 11. Therefore, the sound absorption filler 3 can be used while eliminating the particulate matters in the gas, so that the breathing machine can be miniaturized and the inhaled gas can be healthy while achieving noise reduction.

[0045] Referring to Fig. 1, the main parameter considered in the selection of the sound-permeable and gas-blocking piece 2 is the sound-permeable ability. Based on the sound-permeable ability, the sound-permeable and gas-blocking piece 2 can be a hard material or a soft material. The hard material includes but is not limited to carbon fiber and glass fiber, and the soft material includes but is not limited to rubber, polyethylene and TPU. In the embodiment, in order to further improve the noise reduction ability, the sound-permeable and gas-blocking piece 2 is preferably a soft material. When the sound passes through the sound-permeable and gas-blocking piece 2, the sound-permeable and gas-blocking piece 2 will vibrate, thereby the energy in the sound can be consumed by means of the vibration, so as to achieve the purpose of improving the noise reduction ability.

[0046] Referring to Fig. 1, in order to make more sound into the sound absorption part 12, the sound absorption part 12 is arranged synchronously with the airflow part 11, specifically, the sound absorption part 12 and the airflow part 11 have the same extension shape. From the cross section of the gas path cavity 1, the airflow part 11 and the sound absorption part 12 are a multi-layer structure, so in the process of the airflow gradually moving forward, sound can continuously pass through the sound-permeable resistance member 2 into the sound absorption part 12, thereby improving the noise reduction capability.

[0047] Referring to Fig. 1, in order to maintain the vibration of the sound-permeable resistance member 2 and further reduce noise, there is a resonance gap between the sound absorption filler 3 and the sound-permeable resistance member 2, so that the sound-permeable resistance member 2 can vibrate, and at the same time, a structure similar to a resonance cavity is formed between the sound absorption filler 3 and the sound-permeable resistance member 2, thereby further eliminating noise.

[0048] The implementation principle of the noise reduction gas path structure of the embodiment of the present application is that sound in the gas can pass through the sound-permeable resistance member 2 into the sound absorption part 12 and then be eliminated by the sound absorption filler 3 in the sound absorption part 12, but the gas will not enter the sound absorption part 12, so the sound absorption filler 3 will not also release particulate matter into the airflow part 11, so the sound absorption filler 3 can be used while eliminating particulate matter in the gas, thereby achieving noise reduction while miniaturizing the size of the breathing machine and making the inhaled gas healthy.

[0049] The embodiment of the present application also discloses a gas path device.

[0050] Referring to Figs. 2 and 3, the gas path device comprises the aforementioned noise reduction gas path structure, a shell 4, and a fan 5, the noise reduction gas path structure is arranged in the shell 4, so the shell 4 has the gas path cavity 1. Meanwhile, the shell also has a power cavity 6, the power cavity 6 is in communication with the gas path cavity 1, and the fan 5 is arranged in the power cavity 6. The gas path device can take advantage of the noise reduction gas path structure to achieve noise reduction while making the inhaled gas healthy and miniaturizing the size of the gas path device itself. In addition, the arrangement of the power cavity 6 makes the gas not immediately enter the fan 5 after leaving the gas path cavity 1, but gradually accumulates in the power cavity 6 and then enters the fan 5, so the flow rate does not change significantly, thereby reducing the generation of additional noise.

[0051] Referring to Figs. 2 and 3, in order to improve the noise reduction capability, first, the gas path cavity 1 is arranged to extend in a serpentine shape, the flow rate of the airflow at the bending part is less than the speed at the straight part, so more sound can pass through the sound-permeable resistance member 2 into the sound absorption part 12 at the bending part, thereby promoting the noise reduction capability. In addition, the extension mode of the gas path cavity 1 also makes the gas path cavity 1 not too large in a certain direction, thereby promoting the miniaturization of the breathing machine.

[0052] Referring to FIG. 2 and FIG. 3, the air flow guide plate 7 is integrally formed at the bending position of the air flow cavity 1, the extension shape of the air flow guide plate 7 corresponds to the bending shape of the air flow cavity 1 at the bending position, so that the air flow can be better guided to turn at the bending position, to weaken the collision between the air flow and the inner wall of the air flow part 11 at the bending position, thereby reducing the generation of new noise, and thus improving the noise reduction capability.

[0053] Referring to FIG. 2 and FIG. 3, the air flow passes through the air flow cavity 1 and the power cavity 6 in turn. Since the air flow cavity 1 is bent and extended in the horizontal direction and the power cavity 6 is located above the air flow cavity 1, during operation, the gas will slowly accumulate in the air flow cavity 1, and the amount of gas in the power cavity 6 will be small and quickly diffuse. Therefore, the gas is saturated in the air flow cavity 1 but has a slow flow rate, and the gas is not saturated in the power cavity 6 but has a fast flow rate. Thus, the pressure difference at the communication position between the air flow cavity 1 and the power cavity 6 will not be too large, thereby reducing the noise at the communication position between the air flow cavity 1 and the power cavity 6.

[0054] Referring to FIG. 2 and FIG. 3, in this embodiment, since the air flow cavity 1 is bent and extended in a serpentine shape and in the horizontal direction, in order to consider the miniaturization of the air flow device, only one sound-transmitting and gas-blocking piece 2 is horizontally arranged, the air flow part 11 is located above, and the sound-absorbing part 12 is located below. Based on this structure, in order to facilitate the installation of the sound-transmitting and gas-blocking piece 2 and more sealingly separate the air flow part 11 and the sound-absorbing part 12, the following arrangements are made: the shell 4 is divided into an upper cover 41 and a lower bottom plate 42, the upper cover 41 has the aforementioned power cavity 6, the lower side of the upper cover 41 is provided with an air flow groove 8, the groove opening of the air flow groove 8 is covered by the sound-transmitting and gas-blocking piece 2 to form the aforementioned air flow part 11; the lower bottom plate 42 is located on the side of the sound-transmitting and gas-blocking piece 2 away from the upper cover 41, the lower bottom plate 42 and the side surface of the sound-transmitting and gas-blocking piece 2 away from the upper cover 41 form the aforementioned sound-absorbing part 12, and the lower bottom plate 42 and the upper cover 41 clampingly fix the sound-transmitting and gas-blocking piece 2, so that the sound-transmitting and gas-blocking piece 2 will be compressed and deformed.

[0055] Referring to FIG. 2 and FIG. 3, the cooperation structure among the sound-permeable and gas-blocking member 2, the upper cover 41 and the lower bottom plate 42 has the following advantages: first, the sound-permeable and gas-blocking member 2 directly separates the upper cover 41 and the lower bottom plate 42 in terms of structural distribution, so that the separation and sealing between the air flow part 11 and the sound absorption part 12 is better; second, the sound-permeable and gas-blocking member 2 is clamped and fixed by the upper cover 41 and the lower bottom plate 42, so that the sound-permeable and gas-blocking member 2 is compressed and deformed, and better connection tightness between the sound-permeable and gas-blocking member 2 and the upper cover 41 and the lower bottom plate 42 is achieved, and meanwhile, the sound-permeable and gas-blocking member 2, the upper cover 41 and the lower bottom plate 42 are more convenient to assemble and disassemble; third, because the sound-permeable and gas-blocking member 2 is made of elastic material, the vibration generated during the operation of the fan 5 is first weakened when passing through the sound-permeable and gas-blocking member 2, and then transmitted to the lower bottom plate 42, so that the vibration amplitude of the whole air path device is reduced, and the noise generated by the air path device is further reduced.

[0056] The implementation principle of the air path device of the embodiment of the present application is as follows: first, the function of the noise reduction air path structure can reduce noise while miniaturizing the volume of the air path device and making the delivered air healthy; second, the vibration generated during the operation of the fan 5 is weakened before being transmitted to the lower bottom plate 42 by clamping and fixing the sound-permeable and gas-blocking member 2 made of elastic material by the upper cover 41 and the lower bottom plate 42, so that the vibration amplitude of the whole air path device is smaller, and the noise reduction capability of the air path device is improved by eliminating other noises.

[0057] The embodiment of the present application also discloses a breathing machine. The breathing machine comprises the air path device described above, wherein the lower bottom plate 42 in the air path device is part of the shell structure of the breathing machine, so that the breathing machine can weaken the noise generated by air flow and the noise generated by the vibration of the fan 5, thereby realizing noise reduction while miniaturizing the volume, and the air inhaled by people is also healthy.

[0058] The above are the preferred embodiments of the present application, which do not limit the protection scope of the present application, and therefore: any equivalent changes made on the structure, shape and principle of the present application should be covered within the protection scope of the present application.

Claims

1. A noise reduction air path structure, characterized by: The application relates to a noise reduction air path structure. The application relates to a noise reduction air path structure. The application relates to a noise reduction air path structure. The application relates to a noise reduction air path structure.

2. The noise reduction air path structure of claim 1, wherein: The application relates to a noise reduction air path structure.

3. The noise reduction air path structure of claim 2, wherein: The application relates to a noise reduction air path structure.

4. The noise reduction air path structure of claim 2, wherein: The application relates to a noise reduction air path structure.

5. An air path device characterized by: The application relates to a noise reduction air path structure.

6. The air path device according to claim 5, characterized by: The application relates to a noise reduction air path structure.

7. The air path device according to claim 6, characterized by: The application relates to a noise reduction air path structure.

8. The air path device according to claim 6, characterized by: The application relates to a noise reduction air path structure.

9. The air path device according to claim 8, characterized by: The application relates to a noise reduction air path structure.

10. A breathing machine characterized by: The application relates to a noise reduction air path structure. The application relates to a noise reduction air path structure. The application relates to a noise reduction air path structure. The application relates to a noise reduction air path structure. The application relates to a noise reduction air path structure. The application relates to a noise reduction air path structure. The application relates to a noise reduction air path structure. The application relates to a noise reduction air path structure. The application relates to a noise reduction air path structure. The application relates to a noise reduction air path structure. The application relates to a noise reduction air path structure. The application relates to a noise reduction air path structure. The application relates to a noise reduction air path structure. The application relates to a noise reduction air path structure. 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