CN219301028U - Mute mechanism and gas water heater - Google Patents

Abstract

The utility model provides a silencing mechanism and a gas water heater, and relates to the technical field of gas water heaters. The silencing mechanism comprises a silencing piece which is used for being installed in a shell of the gas water heater; the silencing piece is provided with an air inlet groove, an opening of the air inlet groove is communicated with an air inlet of the gas water heater, and a groove and a sleeving hole for sleeving a smoke exhaust pipeline are formed in the bottom wall of the air inlet groove at intervals; the lateral wall of recess is equipped with the air outlet. The mute mechanism provided by the utility model solves the technical problem of loud noise of the gas water heater in the prior art.

Description

Mute mechanism and gas water heater

Technical Field

The utility model relates to the technical field of gas water heaters, in particular to a silencing mechanism and a gas water heater.

Background

Noise generated during the operation of the gas water heater can cause the elder, children and operators to generate dysphoria, headache, palpitation and other adverse reactions, and the gas water heater can seriously influence physical and mental health after long-term use.

The noise generated during the operation of the gas water heater comprises the noise generated by the air inlet of the fan and the noise generated by the combustion. Referring to fig. 1 and 2, air required by the existing gas water heater during combustion mainly enters from the opening of the bottom shell, then enters from the bottom of the combustion mechanism after being extracted by the fan, is mixed with the gas for combustion, and has high air intake noise at the opening of the bottom shell. When the fuel gas burns in the combustion mechanism, a small part of noise generated by combustion is refracted by the shell of the combustion mechanism and then is transmitted outdoors from the smoke exhaust pipe, and most of sound overflows or penetrates through the holes of the bottom shell after passing through the combustion mechanism or transmitting from the part connecting gaps of each combustion mechanism, so that the noise is loud.

Disclosure of Invention

The utility model aims to provide a silencing mechanism and a gas water heater so as to solve the technical problem that the gas water heater in the prior art is loud in noise.

In order to solve the technical problems, the technical scheme provided by the utility model is as follows:

in a first aspect, the utility model provides a muting mechanism comprising a muting piece for installation in a housing of a gas water heater;

the silencing piece is provided with an air inlet groove, an opening of the air inlet groove is used for being communicated with an air inlet of the gas water heater, and a groove and a sleeving hole for sleeving a smoke exhaust pipeline are formed in the bottom wall of the air inlet groove at intervals;

and the side wall of the groove is provided with an air outlet.

Optionally, the cross section of the groove is polygonal.

Optionally, the grooves are provided in plurality, and the grooves are arranged at intervals along the circumference of the sleeve joint hole.

Optionally, the air outlet is arranged on the side wall of the groove far away from the sleeving hole.

Optionally, the air outlet is provided with a plurality of air outlets, and a plurality of air outlets are arranged at intervals along the width direction of the groove.

Optionally, the silencing mechanism further comprises a noise reduction sheet;

the noise reduction piece is provided with a mounting hole communicated with the sleeving hole, and the noise reduction piece is mounted on the silencing piece.

Optionally, a connecting groove is formed in the side wall of the noise reduction sheet, and the sleeving hole is sleeved on the bottom wall of the connecting groove.

Optionally, the noise reduction sheet is made of noise reduction materials.

In a second aspect, the present utility model provides a gas water heater comprising a housing, a combustion mechanism and a silencing mechanism as described in any of the preceding claims;

the combustion mechanism and the silencing mechanism are both arranged in the shell;

the shell comprises an air inlet which is communicated with an air inlet groove in the silencing mechanism;

the combustion mechanism comprises a smoke exhaust pipeline which is inserted into a sleeve joint hole in the mute mechanism and extends out of the shell.

Optionally, the air inlet is arranged at the top of the shell, and a silencing piece in the silencing mechanism is arranged on the inner top wall of the shell.

Optionally, the mute piece is detachably connected with the inner top wall of the shell.

Optionally, the shell comprises a bottom shell and an air inlet pipe;

the top wall of the bottom shell is provided with a through hole, and the smoke exhaust pipeline extends out of the through hole;

the air inlet pipe is arranged on the outer top wall of the bottom shell, sleeved with the smoke exhaust pipeline and provided with the air inlet communicated with the through hole.

In summary, the technical effects achieved by the utility model are analyzed as follows:

the silencing mechanism provided by the utility model comprises a silencing piece arranged in a shell of the gas water heater; the silencing piece is provided with an air inlet groove, an opening of the air inlet groove is communicated with an air inlet of the gas water heater, and a groove and a sleeving hole for sleeving a smoke exhaust pipeline are formed in the bottom wall of the air inlet groove at intervals; the lateral wall of recess is equipped with the air outlet. Air flows through the air inlet groove and the groove through the air inlet of the gas water heater and then flows into the shell of the gas water heater from the air outlet, so that sound is refracted in the mute piece, and air inlet noise is reduced; and because the air does not directly flow into the shell of the gas water heater, the sound can be refracted for a plurality of times in the shell of the gas water heater, the propagation kinetic energy of the sound is weakened, and the air inlet noise is further reduced. In addition, the air inlet groove of the silencing piece is communicated with the air inlet of the gas water heater, and the sleeve joint hole of the air inlet groove is sleeved with the smoke exhaust pipeline, so that the air inlet of the gas water heater is adjacent to the smoke exhaust pipeline, for example, the smoke exhaust pipeline is arranged on the top wall of the shell, and the silencing piece is also arranged on the top wall of the shell; the combustion noise propagation path is divided into a noise propagation path in the combustion mechanism and a noise propagation path outside the combustion mechanism, and because the mute piece and the smoke exhaust pipeline are both positioned on the top wall of the shell, the combustion external noise propagation path is completely opposite to the air inlet path of the fan, part of propagation kinetic energy of sound is mutually counteracted, and the overall noise is weakened; near the mute piece, part of combustion noise is blocked by the mute piece and is spread downwards again, so that the combustion noise is difficult to be transmitted; part of combustion noise is refracted for many times in the mute, so that propagation kinetic energy is weakened, and noise is reduced.

Drawings

In order to more clearly illustrate the embodiments of the present utility model or the technical solutions in the prior art, the drawings that are needed in the description of the embodiments or the prior art will be briefly described, and it is obvious that the drawings in the description below are some embodiments of the present utility model, and other drawings can be obtained according to the drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic view of the internal structure of a gas water heater in the prior art;

FIG. 2 is a schematic diagram of a prior art gas water heater;

fig. 3 is a schematic structural diagram of a mute unit in a mute mechanism according to an embodiment of the present utility model at a first viewing angle;

fig. 4 is a schematic structural diagram of a mute member in a mute mechanism according to an embodiment of the present utility model at a second viewing angle;

FIG. 5 is a schematic diagram of the internal structure of a gas water heater according to an embodiment of the present utility model;

FIG. 6 is an enlarged view of a portion of FIG. 5 at A;

fig. 7 is a schematic structural diagram of a noise reduction sheet in a silencing mechanism according to an embodiment of the present utility model at a first view angle;

fig. 8 is a schematic structural diagram of a noise reduction sheet in a silencing mechanism according to an embodiment of the present utility model at a second view angle;

FIG. 9 is a schematic diagram of a gas water heater according to an embodiment of the present utility model in a first view angle;

FIG. 10 is a schematic diagram of a gas water heater according to an embodiment of the present utility model in a second view angle;

FIG. 11 is a schematic diagram of a fan air intake noise propagation path in a gas water heater according to an embodiment of the present utility model;

FIG. 12 is a schematic view of an external noise propagation path of a combustion mechanism in a gas water heater according to an embodiment of the present utility model;

FIG. 13 is a schematic view of the internal noise propagation path of the combustion mechanism in the gas water heater according to the embodiment of the utility model.

Icon:

100-mute; 110-an air inlet groove; 111-grooves; 112-socket holes; 113-an air outlet; 120-bump; 200-noise reduction sheets; 210-mounting holes; 220-connecting grooves; 300-a housing; 310-bottom case; 320-an air inlet pipe; 321-an air inlet; 400-combustion mechanism; 410-fume duct.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the embodiments of the present utility model more apparent, the technical solutions of the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model, and it is apparent that the described embodiments are some embodiments of the present utility model, but not all embodiments of the present utility model. The components of the embodiments of the present utility model generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the utility model, as presented in the figures, is not intended to limit the scope of the utility model, as claimed, but is merely representative of selected embodiments of the utility model. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further definition or explanation thereof is necessary in the following figures.

In the description of the present utility model, it should be noted that, directions or positional relationships indicated by terms such as "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., are directions or positional relationships based on those shown in the drawings, or are directions or positional relationships conventionally put in use of the inventive product, are merely for convenience of describing the present utility model and simplifying the description, and are not indicative or implying that the apparatus or element to be referred to must have a specific direction, be constructed and operated in a specific direction, and thus should not be construed as limiting the present utility model. Furthermore, the terms "first," "second," "third," and the like are used merely to distinguish between descriptions and should not be construed as indicating or implying relative importance.

Furthermore, the terms "horizontal," "vertical," "overhang," and the like do not denote a requirement that the component be absolutely horizontal or overhang, but rather may be slightly inclined. As "horizontal" merely means that its direction is more horizontal than "vertical", and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.

In the description of the present utility model, it should also be noted that, unless explicitly specified and limited otherwise, the terms "disposed," "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present utility model will be understood in specific cases by those of ordinary skill in the art.

Some embodiments of the present utility model are described in detail below with reference to the accompanying drawings. The following embodiments and features of the embodiments may be combined with each other without conflict.

Example 1

The silencing mechanism provided by the embodiment of the utility model comprises a silencing piece 100 which is used for being installed in a shell 300 of a gas water heater; the mute piece 100 is provided with an air inlet groove 110, an opening of the air inlet groove 110 is used for being communicated with an air inlet 321 of the gas water heater, a groove 111 and a sleeve hole 112 for sleeve a smoke exhaust pipeline 410 are arranged on the bottom wall of the air inlet groove 110 at intervals; the side wall of the groove 111 is provided with an air outlet 113. Air flows through the air inlet groove 110 and the groove 111 through the air inlet 321 of the gas water heater and then flows into the shell 300 of the gas water heater from the air outlet 113, so that sound is refracted in the mute piece 100, and air inlet noise is reduced; and because the air does not directly flow into the shell 300 of the gas water heater, the sound can be refracted for a plurality of times in the shell 300 of the gas water heater, the propagation kinetic energy of the sound is weakened, and the air inlet noise is further reduced. In addition, the air inlet slot 110 of the mute member 100 is communicated with the air inlet 321 of the gas water heater, and the smoke exhaust pipe 410 is sleeved in the sleeve hole 112 of the air inlet slot 110, so that the air inlet 321 of the gas water heater is adjacent to the smoke exhaust pipe 410, for example, the smoke exhaust pipe 410 is mounted on the top wall of the housing 300, and the mute member 100 is also mounted on the top wall of the housing 300; the combustion noise propagation path is divided into a noise propagation path in the combustion mechanism 400 and a noise propagation path outside the combustion mechanism 400, and because the mute 100 and the smoke exhaust duct 410 are both located at the top wall of the housing 300, the combustion external noise propagation path is completely opposite to the fan air intake path, and part of propagation kinetic energy of sound is mutually offset, and overall noise is attenuated; near the mute 100, part of combustion noise is blocked by the mute 100, and propagates downwards again, so that the combustion noise is difficult to be transmitted; part of the combustion noise is refracted multiple times in the mute 100, the propagation kinetic energy is weakened, and the noise is reduced.

The structure and shape of the muting mechanism are described in detail below:

in an alternative of the embodiment of the present utility model, the cross section of the groove 111 is provided as a polygon.

Specifically, referring to fig. 3 and 4, in the present embodiment, the cross section of the groove 111 is set to be rectangular; of course, it is within the scope of the present utility model to provide the cross-section of the recess 111 with other shapes, such as pentagonal or hexagonal, etc. Preferably, the mute member 100 is made of plastic material.

The cross section of the groove 111 is polygonal, so that the refraction effect on sound is enhanced, and noise is reduced.

In an alternative embodiment of the present utility model, a plurality of grooves 111 are provided, and a plurality of grooves 111 are arranged at intervals along the circumference of the socket hole 112.

Specifically, referring to fig. 3 and 4, in the present embodiment, two grooves 111 are provided, and the two grooves 111 are located at two sides of the socket hole 112, respectively.

The grooves 111 are arranged in a plurality of ways, so that the air inlet quantity is increased to meet the requirements of a gas mechanism in the gas water heater.

In an alternative embodiment of the present utility model, the air outlet 113 is disposed on a side wall of the recess 111 away from the socket hole 112.

Specifically, referring to fig. 11, the arrow points to a fan air intake noise propagation path, and fan air suction is accompanied by wind noise, and the wind noise enters the mute member 100 from the air intake 321, and is refracted and propagated for multiple times in the mute member 100, and then is propagated out from the left and right air outlets 113, and then is propagated into the combustion mechanism 400.

The air outlet 113 is arranged on the side wall of the groove 111 far away from the sleeve joint hole 112, so that the refraction times of wind noise in the mute piece 100 are increased, and the noise reduction effect is enhanced.

In an alternative embodiment of the present utility model, a plurality of air outlets 113 are provided, and a plurality of air outlets 113 are arranged at intervals along the width direction of the groove 111.

Specifically, referring to fig. 4, the air outlets 113 are rectangular, and two air outlets 113 are provided at intervals along the width direction of the groove 111. Of course, it is within the scope of the present utility model to provide the air outlet 113 in other shapes, such as a circular shape.

The air outlets 113 are provided in plurality, so that the air output of the silencing piece 100 is increased to meet the requirements of a gas mechanism in the gas water heater.

In an alternative scheme of the embodiment of the utility model, the silencing mechanism further comprises a noise reduction sheet 200; the noise reduction sheet 200 is provided with a mounting hole 210 communicating with the socket hole 112, and the noise reduction sheet 200 is mounted to the mute 100.

Specifically, referring to fig. 5 to 8, the noise reduction sheet 200 is mounted to the bottom wall of the air inlet duct 110. The noise reduction sheet 200 is provided with mounting holes 210, and the mounting holes 210 are used for sealing in cooperation with the smoke exhaust duct 410.

The noise reduction sheet 200 functions to prevent sound from overflowing from a gap between the mute 100 and the smoke exhaust duct 410 and to absorb sound, thereby reducing noise.

In an alternative scheme of the embodiment of the utility model, the side wall of the noise reduction sheet 200 is provided with a connecting groove 220, and the sleeve hole 112 is sleeved on the bottom wall of the connecting groove 220.

Specifically, the noise reduction sheet 200 is provided in a cylindrical shape, and the connection groove 220 is recessed from the circumferential wall of the noise reduction sheet 200 in a direction near the center and extends in the circumferential direction of the noise reduction sheet 200; the two sidewalls of the connection groove 220 are respectively abutted against the inner wall and the outer wall of the mute member 100.

The side wall of the noise reduction piece 200 is provided with a connecting groove 220, and the bottom wall of the noise reduction piece 100 is clamped in the connecting groove 220, so that the noise reduction piece 200 is installed on the noise reduction piece 100, and a gap between the noise reduction piece 100 and the smoke exhaust pipeline 410 is filled, and the effect of reducing noise is achieved.

In an alternative embodiment of the present utility model, the noise reduction sheet 200 is made of a noise reduction material.

Specifically, the noise reduction sheet 200 is made of rubber, a sound insulation felt, or a sound insulation cotton.

The noise reduction sheet 200 is made of noise reduction materials, and the effect of noise absorption is improved.

Example two

The gas water heater provided by the embodiment of the utility model comprises the silencing mechanism in the first embodiment, so that the gas water heater also has all the beneficial effects in the first embodiment, and the description is omitted.

In an alternative of the embodiment of the present utility model, the gas water heater further comprises a housing 300 and a combustion mechanism 400; the combustion mechanism 400 and the mute mechanism are both mounted within the housing 300; the shell 300 comprises an air inlet 321, and the air inlet 321 is communicated with an air inlet groove 110 in the silencing mechanism; the combustion mechanism 400 includes a smoke exhaust duct 410, and the smoke exhaust duct 410 is inserted into the socket hole 112 in the mute mechanism and extends out of the housing 300.

Specifically, referring to fig. 9 to 13, the combustion mechanism 400 is located at a middle position of the housing 300, and the smoke exhaust duct 410 extends out of the housing 300 after passing through the mute 100.

The combustion mechanism 400 realizes the heating function of the gas water heater, and the shell 300 realizes the supporting function of the combustion mechanism 400 and the silencing mechanism.

In an alternative embodiment of the present utility model, the air inlet 321 is disposed at the top of the housing 300, and the silencing element 100 in the silencing mechanism is mounted on the inner top wall of the housing 300.

Specifically, referring to fig. 11, fig. 11 is a schematic diagram of a noise propagation path of the air intake of the fan, the air intake of the fan is accompanied by wind noise, the wind noise enters the mute member 100 from the top of the housing 300, and the sound is refracted and propagated multiple times in the mute member 100, and then is propagated from the left and right air outlets 113, and then is propagated to the bottom to be sent into the combustion mechanism 400 together with the wind. Compared with the traditional gas water heater structure, the sound can only enter from the top end, and is refracted for many times in the shell 300 of the gas water heater, so that the propagation kinetic energy of the sound is weakened, and the sound is weakened. Referring to fig. 12 and 13, fig. 12 shows the external noise propagation path of the combustion mechanism 400, fig. 13 shows the internal noise propagation path of the combustion mechanism 400, the external noise propagation path of the combustion is completely opposite to the fan air intake path, and part of the propagation kinetic energy of the sound is cancelled, so that the overall noise is attenuated. Near the mute 100, part of the combustion noise is separated by the noise reduction structure and is spread downward again, so that it is difficult to be transmitted. Part of the combustion noise undergoes multiple refractions within the mute 100 and the propagation kinetic energy is attenuated. In addition, the combustion internal noise is partially absorbed by the noise reduction sheet 200 after being propagated to the tip end of the case 300, and the overall noise is attenuated.

In an alternative embodiment of the present utility model, the mute member 100 is detachably connected to the inner top wall of the housing 300.

Specifically, referring to fig. 3, the open end of the air inlet slot 110 is provided with a protrusion 120, and the protrusion 120 extends along the circumferential direction of the air inlet slot 110. The screw is coupled to the inner top wall of the housing 300 through the boss 120.

The connection of the mute member 100 to the housing 300 is achieved by the screws, and the mute member 100 is easily installed and removed.

In an alternative of the embodiment of the present utility model, the case 300 includes a bottom case 310 and an air inlet duct 320; the top wall of the bottom case 310 is provided with a through hole, and the smoke exhaust duct 410 extends out of the through hole; the air inlet pipe 320 is installed on the outer top wall of the bottom shell 310, sleeved with the smoke exhaust pipe 410, and provided with an air inlet 321 communicated with the through hole.

Specifically, referring to fig. 6, a plurality of air inlets 321 are provided, and a plurality of air inlets 321 are disposed at intervals along the circumferential direction of the air inlet pipe 320. Preferably, the axis of the smoke exhaust duct 410 and the axis of the air inlet pipe 320 are all collinear with the axis of the through hole.

The smoke exhaust pipe 410 extends out of the through hole to realize outward discharge of smoke and the like generated by combustion of the gas mechanism; the smoke exhaust pipe 410 is sleeved on the air inlet pipe 320, so that holes are formed in the top wall of the bottom shell 310, sound propagation kinetic energy can be mutually offset, and noise propagation is reduced.

The working principle of the gas water heater is described as follows:

switching on the power supply of the gas water heater, pressing a start button on a control panel of the gas water heater, and starting the fan to operate; sound is transmitted from the top end of the bottom shell 310, and after reaching the inside of the mute piece 100, the sound is refracted for multiple times and transmitted to the lower part of the bottom shell 310, and enters the combustion mechanism 400 to start combustion; combustion noise is generated in the housing 300 after combustion; during combustion, a part of noise is spread from the outside of the combustion system, the propagation path of the part of combustion noise is completely opposite to the air inlet path of the fan, kinetic energy hedging occurs, the kinetic energy is counteracted, the part of noise is refracted in the mute 100 for multiple times, and the dynamic propagation kinetic energy is counteracted; part of the combustion noise is blocked at the mute 100, the sound is hard to be transmitted out, and the sound is folded back again; the other part of noise is spread from the combustion system, the combustion internal noise is emitted from the combustion mechanism 400, transmitted to the direction of the smoke exhaust pipeline 410 and then discharged, and the sound is diluted and the noise is low because the smoke exhaust pipeline 410 is connected with the outside of the discharge chamber; therefore, the noise is greatly reduced by the combustion external noise path through multiple refraction, blocking and offset effects.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present utility model, and not for limiting the same; although the utility model has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the utility model.

Claims (12)

1. A muting mechanism, comprising: a mute piece (100) for being installed in a housing (300) of a gas water heater;

the silencing piece (100) is provided with an air inlet groove (110), an opening of the air inlet groove (110) is used for being communicated with an air inlet (321) of the gas water heater, a groove (111) and a sleeving hole (112) used for sleeving a smoke exhaust pipeline (410) are formed in the bottom wall of the air inlet groove (110) at intervals;

an air outlet (113) is arranged on the side wall of the groove (111).

2. A muting mechanism according to claim 1, characterized in that the cross section of the groove (111) is provided as a polygon.

3. The muting mechanism according to claim 1, wherein a plurality of grooves (111) are provided, and a plurality of the grooves (111) are provided at intervals along the circumferential direction of the socket hole (112).

4. The muting mechanism according to claim 1, characterized in that the air outlet (113) is provided in a side wall of the recess (111) remote from the socket hole (112).

5. The muting mechanism according to claim 4, wherein a plurality of the air outlets (113) are provided, and a plurality of the air outlets (113) are arranged at intervals in a width direction of the groove (111).

6. The muting mechanism according to claim 1, characterized in that the muting mechanism further comprises a noise reduction sheet (200);

the noise reduction sheet (200) is provided with a mounting hole (210) communicated with the sleeving hole (112), and the noise reduction sheet (200) is mounted on the silencing piece (100).

7. The silencing mechanism as recited in claim 6, wherein a side wall of the noise reduction sheet (200) is provided with a connecting groove (220), and the socket hole (112) is sleeved on a bottom wall of the connecting groove (220).

8. The muting mechanism according to claim 6, wherein the noise reduction sheet (200) is made of a noise reduction material.

9. A gas water heater, characterized by comprising a housing (300), a combustion mechanism (400) and a muting mechanism according to any one of claims 1-8;

the combustion mechanism (400) and the silencing mechanism are both arranged in the shell (300);

the shell (300) comprises an air inlet (321), and the air inlet (321) is communicated with an air inlet groove (110) in the silencing mechanism;

the combustion mechanism (400) comprises a smoke exhaust pipeline (410), and the smoke exhaust pipeline (410) is inserted into a sleeve joint hole (112) in the silencing mechanism and extends out of the shell (300).

10. The gas water heater as claimed in claim 9, wherein the air inlet (321) is provided at the top of the housing (300), and the silencing member (100) of the silencing mechanism is mounted to the inner top wall of the housing (300).

11. The gas water heater according to claim 10, wherein the silencing element (100) is detachably connected to the inner top wall of the housing (300).

12. The gas water heater according to claim 10, wherein the housing (300) comprises a bottom shell (310) and an air inlet pipe (320);

the top wall of the bottom shell (310) is provided with a through hole, and the smoke exhaust pipeline (410) extends out of the through hole;

the air inlet pipe (320) is arranged on the outer top wall of the bottom shell (310), is sleeved with the smoke exhaust pipeline (410), and is provided with the air inlet (321) communicated with the through hole.

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