Silencing assembly and sweeping robot

Abstract

The invention relates to the technical field of household appliances, and discloses a silencing assembly and a sweeping robot, the silencing assembly comprises a shell, an air inlet, a first expansion cavity and an air outlet which are sequentially communicated are formed in the shell, and the sectional area of the first expansion cavity is larger than the sectional area of the air inlet and the sectional area of the air outlet; one end of the inner insertion pipe is connected to the air inlet and / or the air outlet, the other end of the inner insertion pipe extends into the first expansion cavity, and the cross section area of the inner insertion pipe is smaller than that of the first expansion cavity. According to the silencing assembly, sound waves in a certain passing frequency range can be eliminated through the inner inserting pipe, so that the noise reduction effect of the silencing assembly is improved, and the user experience can be improved. Therefore, the noise reduction assembly can effectively reduce the noise of the air duct, the material cost of the noise reduction assembly is reduced, and the aerodynamic performance of the sweeping robot cannot be greatly lost.

Description

Technical Field

[0001] The present invention relates to the technical field of household appliances, and in particular to a muffler component and a sweeping robot. Background Art

[0002] A fan is installed in the dust exhaust duct of the sweeper, and the fan drives the air flow to blow out from the air outlet. However, the air flow will generate noise due to sudden changes in speed and direction.

[0003] In the related art, some silencer components include an expansion chamber arranged in the dust exhaust duct of the sweeper, with an air inlet and an air outlet respectively provided at both ends of the expansion chamber. The cross-sectional area of ​​the air inlet and the air outlet is smaller than the cross-sectional area of ​​the expansion chamber, which can reduce the noise generated by the airflow. However, the noise reduction effect of this silencer method is still insufficient, and there is still the problem that the noise generated by the air duct affects the user experience. Summary of the invention

[0004] In view of this, the present invention provides a silencer component and a sweeping robot to solve the problem that the noise reduction effect of the silencer component in the related art is poor and the noise generated by the air duct affects the user experience.

[0005] In a first aspect, the present invention provides a sound-absorbing component, comprising:

[0006] A shell, wherein an air inlet, a first expansion cavity and an air outlet are sequentially connected, and a cross-sectional area of ​​the first expansion cavity is larger than a cross-sectional area of ​​the air inlet and the air outlet;

[0007] The inner tube has one end connected to the air inlet and / or the air outlet and the other end extending into the first expansion cavity. The cross-sectional area of ​​the inner tube is smaller than the cross-sectional area of ​​the first expansion cavity.

[0008] Beneficial effect: During use of the silencer assembly of the embodiment of the present invention, air flows into the first expansion chamber through the air inlet and is then discharged through the air outlet. Since the cross-sectional area of ​​the first expansion chamber is larger than the cross-sectional areas of the air inlet and the air outlet, the sound waves can continuously reflect and collide after entering the first expansion chamber and are eventually converted into heat energy and dissipated. It has a good noise reduction effect within a wider sound wave frequency range.

[0009] On this basis, one end of the inner tube extends into the first expansion cavity, and the sound waves transmitted into the first expansion cavity can be reflected after encountering different interfaces of the inner tube, and the reflected sound waves are phase-shifted with the original sound waves. Since the amplitudes of the sound waves are equal, they can interfere with each other and cancel each other out when the phases are opposite, so the silencer assembly of the embodiment of the present application can eliminate the sound waves within a certain frequency range through the inner tube, thereby improving the noise reduction effect of the silencer assembly and improving the user experience.

[0010] Therefore, the silencer assembly of this embodiment can effectively reduce the air duct noise, reduce the material cost of the silencer assembly, and will not cause significant loss to the aerodynamic performance of the sweeping robot.

[0011] In an optional embodiment, the inner cannula comprises:

[0012] A first inner insert tube connected to the air inlet;

[0013] The second inner insert tube is connected to the air outlet, and the length of the first inner insert tube is greater than the length of the second inner insert tube.

[0014] Beneficial effect: Through such an arrangement, the first inner tube and the second inner tube can respectively eliminate sound waves of different passing frequencies, thereby further improving the noise reduction effect of the silencer assembly.

[0015] In an optional embodiment, the depth of the first expansion cavity is l;

[0016] The length of the first inner tube is l1, l1=l / 2; and / or,

[0017] The length of the second inner tube is l2, where l2=l / 4.

[0018] Beneficial effect: Through such an arrangement, when an inner tube with l1=l / 2 is inserted, odd-numbered multiples of the 1 / 2 wavelength can be eliminated; when an inner tube with l2=l / 4 is inserted, even-numbered multiples of the 1 / 2 wavelength can be eliminated; when the first inner tube and the second inner tube are simultaneously arranged in the first expansion cavity, theoretically, all noises of the passing frequencies can be covered.

[0019] In an optional embodiment, the muffler assembly further includes a connecting pipe connected between the first inner insert pipe and the second inner insert pipe, and a plurality of first through holes are provided on the connecting pipe.

[0020] Beneficial effect: The first expansion cavity will bring greater resistance loss to the aerodynamic equipment due to the sudden expansion and contraction of the channel cross section, especially when applied to the dust exhaust duct of the sweeper with a high air flow velocity, which will seriously affect its aerodynamic performance.

[0021] The silencer assembly of the embodiment of the present application adds a connecting pipe between the first inner tube and the second inner tube, thereby connecting the first inner tube and the second inner tube, and the shape trend of the connecting pipe is consistent with the first expansion cavity. For sound waves, since the connecting pipe is provided with a first through hole, the first expansion cavity still maintains the acoustic impedance change caused by the cross-sectional mutation. As for aerodynamic performance, the setting of the connecting pipe can greatly reduce the aerodynamic performance pressure loss when flowing to the next cavity.

[0022] Therefore, the silencer assembly of the embodiment of the present application can significantly reduce the pressure loss of the aerodynamic performance flowing to the next cavity while ensuring its silencer performance.

[0023] In an optional embodiment, the perforation rate of the connecting pipe is greater than or equal to 30%.

[0024] Beneficial effect: When the perforation rate of the connecting tube is within the above range, the perforation rate of the connecting tube is large enough for sound waves, and the change of acoustic impedance caused by the sudden change of cross section is still maintained, thereby avoiding the influence on the sound insulation performance of the first expansion cavity.

[0025] In an optional embodiment, the sound-absorbing component further comprises:

[0026] The second expansion chamber is arranged in the shell and has an air inlet end and an air outlet end. The air inlet end of the second expansion chamber is connected with the air outlet, and the cross-sectional area of ​​the second expansion chamber is larger than the cross-sectional area of ​​the air outlet.

[0027] Beneficial effect: Since the cross-sectional area of ​​the second expansion cavity is larger than the cross-sectional area of ​​the air outlet, the sound waves can be continuously reflected and collided after entering the second expansion cavity, and finally converted into heat energy and dissipated, thereby further improving the silencing effect of the silencing assembly.

[0028] In an optional embodiment, the sound-absorbing component further comprises:

[0029] The air outlet cavity is arranged in the shell body and has an air inlet end and an air outlet end. The air inlet end of the air outlet cavity is communicated with the air outlet end of the second expansion cavity.

[0030] Beneficial effect: The air outlet cavity can further smoothly rectify the airflow discharged from the silencer assembly, thereby reducing the eddy current noise at the outlet of the silencer assembly, so as to further reduce the silencer effect of the silencer assembly.

[0031] In an optional embodiment, the sound-absorbing component further comprises:

[0032] a partition wall, separating the second expansion cavity and the air outlet cavity, wherein a plurality of second through holes are provided on the partition wall; and / or,

[0033] A cavity wall on one side of the air outlet cavity is a first mesh wall, and an air outlet end of the air outlet cavity is connected with mesh holes of the first mesh wall.

[0034] Beneficial effect: The partition wall with multiple second through holes has a certain rectifying effect, because the vortex airflow generated by the rotating suction of the fan has a high flow velocity, and the main trend of the flow direction is to be delivered along the tangential direction of the fan rotation. The flow field is relatively complex. Rectification through the partition wall can make the airflow flow direction consistent with the air supply trend of the current flow channel and reduce the vortex inside the air duct.

[0035] In an optional embodiment, the sound-absorbing component further comprises:

[0036] The air inlet cavity is arranged in the shell and has an air inlet end and an air outlet end. The air outlet end of the air inlet cavity is connected with the air inlet.

[0037] In an optional embodiment, a cavity wall on one side of the air inlet cavity is a second mesh wall, and an air inlet end of the air inlet cavity is connected to the meshes of the second mesh wall.

[0038] Beneficial effect: The first mesh wall has a certain rectifying effect, because the vortex airflow generated by the rotating suction of the fan has a high flow velocity, and the main trend of the flow direction is to be delivered along the tangential direction of the fan rotation. The flow field is relatively complex. Rectification through the first mesh wall can make the airflow direction conform to the air supply trend of the current flow channel and reduce the vortex inside the air duct.

[0039] In an optional embodiment, the first expansion chamber is arranged on one side of the air inlet chamber, the air flow direction in the first expansion chamber is arranged at an angle with the air flow direction in the air inlet chamber, the first expansion chamber is in the shape of a curved tube, and is connected between the air inlet chamber and the first expansion chamber.

[0040] Beneficial effect: Through such an arrangement, the space in the silencer assembly can be reasonably allocated, thereby making the silencer structure simpler and more compact. The bent pipe structure can reduce the space required to be occupied by the first expansion cavity while ensuring the length of the first expansion cavity.

[0041] In an optional embodiment, the sound-absorbing component further comprises:

[0042] The air suction chamber is arranged in the shell and is connected with the air inlet end of the air inlet chamber;

[0043] The fan is arranged in the air suction cavity and can deliver air toward the air inlet end of the air inlet cavity.

[0044] Beneficial effect: During the use of the silencer assembly, the fan can generate strong suction and suck the airflow into the suction chamber, and then pass through the air inlet chamber, the first expansion chamber and the second expansion chamber in sequence, and finally be discharged through the air outlet chamber.

[0045] In a second aspect, the present invention further provides a sweeping robot, comprising:

[0046] A main body, wherein a dust collection box is provided in the main body;

[0047] The silencer assembly of the first aspect of the present invention has an air inlet end which is connected to the dust collecting box.

[0048] Beneficial effect: The sweeping machine of the present invention includes or uses the silencer assembly of the first aspect of the present invention, and thus has its beneficial effect, namely, it can eliminate sound waves within a certain frequency range through the inner insert tube, thereby improving the noise reduction effect of the silencer assembly and improving the user experience.

[0049] Therefore, the sweeping robot of this embodiment can effectively reduce the air duct noise, reduce the material cost of the silencer component, and will not cause a large loss to the aerodynamic performance of the sweeping robot. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0051] Figure 1 An exploded view of a muffler assembly according to an embodiment of the present invention;

[0052] Figure 2 for Figure 1 a cross-sectional view of the muffler assembly shown;

[0053] Figure 3 for Figure 1 A cross-sectional view of the muffler assembly shown at another angle;

[0054] Figure 4 A cross-sectional view of a first expansion cavity of a muffler assembly according to an embodiment of the present invention;

[0055] Figure 5 is a cross-sectional view of the muffler assembly according to an embodiment of the present invention at another angle;

[0056] Figure 6 for Figure 5 The cross-sectional view of the muffler assembly shown has its fan hidden for the sake of showing the structure of the suction chamber;

[0057] Figure 7 is a sound loss simulation curve of the muffler assembly according to an embodiment of the present invention;

[0058] Figure 8 A simulated cloud diagram of the aerodynamic performance of the silencer assembly of the embodiment of the present invention when no connecting pipe is provided;

[0059] Fig. 9 This is a simulated cloud diagram of the aerodynamic performance of the silencer assembly of an embodiment of the present invention after the connecting pipe is provided.

[0060] Description of reference numerals:

[0061] 1. Shell; 101. Air inlet; 102. First expansion cavity; 103. Air outlet; 104. Upper shell; 105. Lower shell;

[0062] 2. Inner cannula; 201. First inner cannula; 202. Second inner cannula;

[0063] 3. connecting pipe; 301. first through hole;

[0064] 4. air inlet cavity; 401. second mesh wall;

[0065] 5. Second expansion chamber;

[0066] 6. Air outlet cavity; 601. Partition wall; 602. Second through hole; 603. First mesh wall;

[0067] 7. Inspiratory cavity;

[0068] 8. Fan. DETAILED DESCRIPTION

[0069] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0070] During the operation of the dust collection pile of the sweeping robot, the fan used in the dust exhaust duct has a large suction force, and there are high levels of wind speed and pressure at its outlet, and the airflow will generate noise due to sudden changes in speed and direction.

[0071] In the related art, sweeping robots generally reduce the noise generated by the dust exhaust duct by installing sound-absorbing materials in the duct. However, in the high suction mode, the noise generated by the duct is still an important factor affecting the user experience.

[0072] Furthermore, in the related technologies, the noise reduction of sweeping robots is mostly achieved by diverting and reducing the pressure in the air ducts, and adding structures such as sound insulation cotton to the air outlet or side walls. This not only requires a larger layout space and uses a large amount of sound insulation cotton, resulting in high material costs; in addition, the sound insulation cotton has a large wind resistance and pressure loss, which will also greatly reduce the dust removal performance, and it is impossible to eliminate peak noise and reduce noise in specific frequency bands.

[0073] Combine the following Figures 1 to 9 , describing an embodiment of the present invention.

[0074] According to an embodiment of the present invention, on one hand, a muffler assembly is provided, comprising a shell 1 and an inner tube 2.

[0075] The housing 1 is provided with an air inlet 101, a first expansion cavity 102 and an air outlet 103 which are connected in sequence. The cross-sectional area of ​​the first expansion cavity 102 is larger than the cross-sectional area of ​​the air inlet 101 and the air outlet 103. One end of the inner tube 2 is connected to the air inlet 101 and / or the air outlet 103, and the other end extends into the first expansion cavity 102. The cross-sectional area of ​​the inner tube 2 is smaller than the cross-sectional area of ​​the first expansion cavity 102.

[0076] During use of the silencer assembly of the embodiment of the present invention, air flows into the first expansion chamber 102 through the air inlet 101 and is then discharged through the air outlet 103. Since the cross-sectional area of ​​the first expansion chamber 102 is larger than the cross-sectional areas of the air inlet 101 and the air outlet 103, the sound waves can continuously reflect and collide after entering the first expansion chamber 102 and are eventually converted into heat energy and dissipated. It has a good noise reduction effect within a wider sound wave frequency range.

[0077] On this basis, one end of the inner tube 2 extends into the first expansion cavity 102, and the sound waves transmitted into the first expansion cavity 102 can be reflected after encountering different interfaces of the inner tube 2, and the reflected sound waves are different in phase from the original sound waves. Since the amplitudes of the sound waves are equal, they can interfere with each other and cancel each other out when the phases are opposite, so the silencer assembly of the embodiment of the present application can eliminate the sound waves within a certain frequency range through the inner tube 2, thereby improving the noise reduction effect of the silencer assembly and improving the user experience.

[0078] Therefore, the silencer assembly of this embodiment can effectively reduce the air duct noise, reduce the material cost of the silencer assembly, and will not cause significant loss to the aerodynamic performance of the sweeping robot.

[0079] In one embodiment, the depth and cross-sectional area of ​​the first expansion cavity 102 are preferably designed according to the characteristics of the noise source so that the silencing frequency of the expansion cavity is consistent with the peak frequency of the noise source, thereby achieving the effect of eliminating the noise peak and reducing the total noise value.

[0080] Next, the parameter selection process of the first expansion cavity 102 is described:

[0081] First, the expansion ratio of the first expansion cavity 102 is obtained according to the size of the product to be silenced that can be used to accommodate the first expansion cavity 102 and the noise level that needs to be reduced.

[0082] The expansion ratio of the first expansion cavity 102 is obtained by the following formula:

[0083] ΔL=10lg[1+1 / 4(m-1 / m) 2 sin 2 kl];

[0084] Where:

[0085] ΔL is the sound attenuation of a single expansion chamber, in dm;

[0086] l is the depth of the first expansion cavity 102, in m;

[0087] K is the wave number, in m -1 ;

[0088] The wave number is obtained by the following formula:

[0089] k = 2πf / c;

[0090] Where c is the speed of sound, in m / s;

[0091] f is the frequency in Hz.

[0092] As a convertible implementation, the expansion ratio can also be selected to be obtained by looking up a table in a book. For example, in one embodiment, the noise reduction target of the product to be noise reduced is 15dB, and the expansion ratio of a single-section expansion cavity is 12.

[0093] Next, the equivalent diameter of the first expansion cavity 102 is obtained according to the main frequency domain segment of the noise of the product to be noise-reduced.

[0094] The lower limit noise reduction frequency and the lower limit noise reduction frequency of the expansion cavity can be obtained by the following formula:

[0095]

[0096] Where:

[0097] C is the speed of sound in air, in m / s;

[0098] D is the average equivalent diameter of the first expansion cavity 102, in m;

[0099] S is the cross-sectional area of ​​the air inlet 101 and the air outlet 103 of the first expansion cavity 102, in m 2 ;

[0100] V is the volume of the first expansion cavity 102, in m 3 ;

[0101] L is the depth of the first expansion cavity 102, in meters.

[0102] Exemplarily, in one embodiment, the main frequency domain of the motor noise of the sweeping robot is 800-9000 Hz, so it can be known that the upper and lower cutoff frequency intervals of the required expansion cavity are roughly within the range of 800-10000 Hz.

[0103] According to the internal dimensions of the sweeping robot, the equivalent diameter of the expansion cavity is selected to be 45.6 mm, and the expansion ratio of the first expansion cavity 102 is 12, so the diameters of the air inlet 101 and the air outlet 103 are 14.86 mm;

[0104] If you want to achieve a silencer frequency below 1000HZ, based on the product size and space, and combined with the following formula, the selected expansion cavity depth is 58.3mm, which can achieve silencer with upper and lower cutoff frequencies of 700~9100HZ, which is close to the required silencer frequency range.

[0105] For example, Figure 3 As shown, the diameter of the inner tube 2 is D1, and the cross-sectional area is S1, and the equivalent diameter of the first expansion cavity is D2, and the cross-sectional area is S2.

[0106] Then the expansion ratio of the first expansion cavity 102 is m, m=S2 / S1.

[0107] In an optional embodiment, the inner cannula includes a first inner cannula and a second inner cannula.

[0108] The first inner insert tube is connected to the air inlet, the second inner insert tube is connected to the air outlet, and the length of the first inner insert tube is greater than the length of the second inner insert tube.

[0109] Through such an arrangement, the first inner tube and the second inner tube can respectively eliminate sound waves of different passing frequencies, thereby further improving the noise reduction effect of the silencer assembly.

[0110] In one embodiment, the depth of the first expansion cavity 102 is l;

[0111] The length of the first inner tube 201 is l1, l1=l / 2; and / or,

[0112] The length of the second inner tube 202 is l2, where l2=l / 4.

[0113] By such an arrangement, when an inner tube 2 with l1=l / 2 is inserted, odd-numbered multiples of the 1 / 2 wavelength can be eliminated. When an inner tube 2 with l2=l / 4 is inserted, even-numbered multiples of the 1 / 2 wavelength can be eliminated. When the first inner tube 201 and the second inner tube 202 are both arranged in the first expansion cavity 102, theoretically, all noises of the passing frequencies can be covered.

[0114] The calculation of the depth of the expansion cavity may need to be determined based on multiple factors such as the specific acoustic design, application scenario, and the required noise reduction effect, which is well known to those skilled in the art.

[0115] For example, in the embodiments of the present application, Figure 2As shown in the figure, 1 is the depth of the first expansion cavity 102 in the embodiment of the present invention. When the first expansion cavity 102 is a curved tube and is provided with a first inner tube 201 and a second inner tube 202, the depth of the expansion cavity is shown in the figure 1, which is the sum of the length of the first inner tube 201, the length of the second inner tube 202, and the arc segment between the first inner tube 201 and the second inner tube 202.

[0116] In one embodiment, the muffler assembly further includes a connecting pipe 3 connected between the first inner insert pipe 201 and the second inner insert pipe 202 , and a plurality of first through holes 301 are provided on the connecting pipe 3 .

[0117] The first expansion cavity 102 will bring a large resistance loss to the aerodynamic equipment due to the sudden expansion and contraction of the channel cross section, especially when it is applied to the dust exhaust duct of a sweeper with a high air flow velocity, which will seriously affect its aerodynamic performance.

[0118] The muffler assembly of the embodiment of the present application adds a connecting pipe 3 between the first inner tube 201 and the second inner tube 202, thereby connecting the first inner tube 201 and the second inner tube 202. The shape trend of the connecting pipe 3 is consistent with the first expansion cavity 102. For sound waves, since the connecting pipe 3 is provided with a first through hole 301, the first expansion cavity 102 still maintains the acoustic impedance change caused by the cross-sectional mutation. As for aerodynamic performance, the setting of the connecting pipe 3 can greatly reduce the aerodynamic performance pressure loss when flowing to the next cavity.

[0119] Therefore, the silencer assembly of the embodiment of the present application can significantly reduce the pressure loss of the aerodynamic performance flowing to the next cavity while ensuring its silencer performance.

[0120] In one embodiment, the perforation rate of the connecting tube 3 is greater than or equal to 30%.

[0121] When the perforation rate of the connecting tube 3 is within the above range, the perforation rate of the connecting tube 3 is large enough for sound waves, and the acoustic impedance change caused by the sudden change of the cross section is still maintained, thereby avoiding the noise reduction performance of the first expansion cavity 102 being affected.

[0122] Figure 8 is a simulation cloud diagram in a state where the connecting tube 3 is not connected between the first inner tube 201 and the second inner tube 202. Fig. 9 It is a simulation cloud diagram in the state where the connecting pipe 3 is connected between the first inner tube 201 and the second inner tube 202. By comparison, it can be seen that after the connecting pipe 3 is provided, the aerodynamic loss flowing to the next cavity is greatly reduced.

[0123] In one embodiment, the muffler assembly further comprises a second expansion chamber 5 .

[0124] The second expansion chamber 5 is disposed in the housing 1 and has an air inlet end and an air outlet end. The air inlet end of the second expansion chamber 5 is connected to the air outlet 103 , and the cross-sectional area of ​​the second expansion chamber 5 is greater than the cross-sectional area of ​​the air outlet 103 .

[0125] Since the cross-sectional area of ​​the second expansion chamber 5 is larger than the cross-sectional area of ​​the air outlet 103, the sound waves can be continuously reflected and collided after entering the second expansion chamber 5, and finally converted into heat energy and dissipated, thereby further improving the silencing effect of the silencing assembly.

[0126] Figure 7 In the figure, the series coupling graph is a curve showing the simulated acoustic loss of the first expansion chamber 102 and the second expansion chamber 5 in series with the frequency of the noise source; the muffler graph is a curve showing the simulated acoustic loss of the first expansion chamber 102 with the frequency of the noise source. Figure 7 It can be seen that the transmission loss of the sound wave when the first expansion chamber 102 and the second expansion chamber 5 are connected in series is higher than the transmission loss of the first expansion chamber 102. Therefore, the silencer assembly provided with the first expansion chamber 102 and the second expansion chamber 5 connected in series has a good noise reduction effect in the noise source frequency band of 0 to 9100 Hz, and the noise reduction effect is best in the 1300 Hz and 6500 Hz frequency bands.

[0127] The second expansion cavity 5 may be a columnar cavity or a curved tube. For example, Figure 2 As shown, the depth of the second expansion chamber 5 is the axial span of the inlet and outlet of the second expansion chamber 5, that is, l3.

[0128] In one embodiment, the muffler assembly further includes an air outlet cavity 6 .

[0129] The air outlet cavity 6 is disposed in the housing 1 , and has an air inlet end and an air outlet end. The air inlet end of the air outlet cavity 6 is communicated with the air outlet end of the second expansion cavity 5 .

[0130] The air outlet cavity 6 can further smoothly rectify the airflow discharged from the silencer assembly, thereby reducing the eddy current noise at the outlet of the silencer assembly, so as to further reduce the silencer effect of the silencer assembly.

[0131] As a convertible implementation, in an embodiment not shown in the drawings, the silencer assembly is not provided with an air outlet cavity 6, and the air outlet end of the second expansion cavity 5 directly exhausts air to the outside.

[0132] In one embodiment, the silencer assembly further includes a partition wall 601 and an air outlet cavity 6 .

[0133] The partition wall 601 is separated between the second expansion cavity 5 and the air outlet cavity 6 , and a plurality of second through holes 602 are disposed on the partition wall 601 .

[0134] The partition wall 601 provided with multiple second through holes 602 has a certain rectifying effect. Because the flow velocity of the vortex airflow generated by the rotating suction of the fan 8 is relatively high, and the main trend of the flow direction is to be delivered along the tangential direction of the rotation of the fan 8, the flow field is relatively complex. Rectification through the partition wall 601 can make the airflow flow direction consistent with the air supply trend of the current flow channel, thereby reducing the vortex inside the air duct.

[0135] One side wall of the air outlet cavity 6 is a first mesh wall 603 , and the air outlet end of the air outlet cavity 6 is connected to the meshes of the first mesh wall 603 .

[0136] The first mesh wall 603 has a certain rectifying effect, because the vortex airflow generated by the rotating suction of the fan 8 has a high flow rate, and the main trend of the flow direction is to be delivered along the tangential direction of the rotation of the fan 8. The flow field is relatively complex. Rectification through the first mesh wall 603 can make the airflow direction conform to the air supply trend of the current flow channel and reduce the vortex inside the air duct.

[0137] In one embodiment, the muffler assembly further includes an air inlet cavity 4 . The air inlet cavity 4 is disposed in the housing 1 , and has an air inlet end and an air outlet end. The air outlet end of the air inlet cavity 4 is connected to the air inlet 101 .

[0138] In one embodiment, a cavity wall on one side of the air inlet cavity 4 is a second mesh wall 401 , and an air inlet end of the air inlet cavity 4 is connected to the meshes of the second mesh wall 401 .

[0139] The second mesh wall 401 has a certain rectifying effect, because the vortex airflow generated by the rotating suction of the fan 8 has a high flow rate, and the main trend of the flow direction is to be delivered along the tangential direction of the rotation of the fan 8. The flow field is relatively complex. Rectification through the second mesh wall 401 can make the airflow direction conform to the air supply trend of the current flow channel and reduce the vortex inside the air duct.

[0140] In one embodiment, the first expansion chamber 102 is disposed at one side of the air inlet chamber 4 , and the air flow direction in the first expansion chamber 102 is arranged at an angle to the air flow direction in the air inlet chamber 4 . The first expansion chamber 102 is in the shape of a curved tube and is connected between the air inlet chamber 4 and the first expansion chamber 102 .

[0141] By such an arrangement, the space in the silencer assembly can be reasonably allocated, thereby making the silencer structure simpler and more compact. The bent pipe structure can reduce the space required to be occupied by the first expansion chamber 102 while ensuring the length of the first expansion chamber 102 .

[0142] As a convertible implementation, the first expansion cavity 102 may also be a cylindrical cavity.

[0143] In one embodiment, the silencer assembly further includes an air suction chamber 9 and a fan 8 .

[0144] The air suction chamber 9 is disposed in the housing 1 and communicated with the air inlet end of the air inlet chamber 4. The fan 8 is disposed in the air suction chamber 9 and can deliver air toward the air inlet end of the air inlet chamber 4.

[0145] During the use of the silencer assembly, the fan 8 can generate a strong suction force and suck the airflow into the suction chamber 7, and then pass through the air inlet chamber 4, the first expansion chamber 102 and the second expansion chamber 5 in sequence, and finally be discharged through the air outlet chamber 6.

[0146] In one embodiment, the housing 1 includes an upper housing 104 and a lower housing 105 that can be engaged with each other. The suction cavity 7 is formed between the upper housing 104 and the lower housing 105 .

[0147] According to an embodiment of the present invention, on the other hand, a sweeping machine is provided, including a main body and a silencer assembly.

[0148] A dust collecting box is arranged in the main body, and the air inlet end of the muffler assembly is connected to the dust collecting box.

[0149] The sweeping machine of the present invention includes or uses the silencer assembly of the first aspect of the present invention, and thus has its beneficial effect, namely, it can eliminate sound waves within a certain passing frequency range through the inner tube 2, thereby improving the noise reduction effect of the silencer assembly and improving the user experience.

[0150] Therefore, the sweeping robot of this embodiment can effectively reduce the air duct noise, reduce the material cost of the silencer component, and will not cause a large loss to the aerodynamic performance of the sweeping robot.

[0151] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope of protection claimed by the present application.

Claims

1. A silencer assembly, characterized in that: include: A shell (1), wherein an air inlet (101), a first expansion cavity (102) and an air outlet (103) are provided in sequence and connected to each other, wherein the cross-sectional area of ​​the first expansion cavity (102) is greater than the cross-sectional areas of the air inlet (101) and the air outlet (103); The inner tube (2) has one end connected to the air inlet (101) and / or the air outlet (103), and the other end extending into the first expansion cavity (102); the cross-sectional area of ​​the inner tube (2) is smaller than the cross-sectional area of ​​the first expansion cavity (102).

2. The sound-absorbing assembly according to claim 1, characterized in that: The inner cannula (2) comprises: A first inner insert tube (201), connected to the air inlet (101); The second inner tube (202) is connected to the air outlet (103), and the length of the first inner tube (201) is greater than the length of the second inner tube (202).

3. The sound-absorbing assembly according to claim 2, characterized in that: The first expansion cavity (102) has a depth of l; The length of the first inner tube (201) is l1, l1=l / 2; and / or, The length of the second inner tube (202) is l2, where l2=l / 4.

4. The sound-absorbing assembly according to claim 2, characterized in that: It also comprises a connecting tube (3) connected between the first inner insert tube (201) and the second inner insert tube (202), wherein the connecting tube (3) is provided with a plurality of first through holes (301).

5. The sound-absorbing assembly according to claim 4, characterized in that: The perforation rate of the connecting pipe (3) is greater than or equal to 30%.

6. The sound-absorbing assembly according to any one of claims 1 to 5, characterized in that: Also includes: The second expansion chamber (5) is arranged in the shell (1) and has an air inlet end and an air outlet end. The air inlet end of the second expansion chamber (5) is connected to the air outlet (103). The cross-sectional area of ​​the second expansion chamber (5) is greater than the cross-sectional area of ​​the air outlet (103).

7. The sound-absorbing assembly according to claim 6, characterized in that: Also includes: An air outlet cavity (6) is arranged in the housing (1) and has an air inlet end and an air outlet end. The air inlet end of the air outlet cavity (6) is connected to the air outlet end of the second expansion cavity (5).

8. The sound-absorbing assembly according to claim 7, characterized in that: Also includes: a partition wall (601) separating the second expansion cavity (5) and the air outlet cavity (6), wherein the partition wall (601) is provided with a plurality of second through holes (602); and / or, One side cavity wall of the air outlet cavity (6) is a first mesh wall (603), and the air outlet end of the air outlet cavity (6) is connected to the meshes of the first mesh wall (603).

9. The sound-absorbing assembly according to claim 6, characterized in that: Also includes: An air inlet cavity (4) is arranged in the housing (1) and has an air inlet end and an air outlet end, and the air outlet end of the air inlet cavity (4) is connected to the air inlet (101).

10. The sound-absorbing assembly according to claim 9, characterized in that: One side cavity wall of the air inlet cavity (4) is a second mesh wall (401), and the air inlet end of the air inlet cavity (4) is in communication with the meshes of the second mesh wall (401).

11. The sound-absorbing assembly according to claim 9, characterized in that: The first expansion chamber (102) is arranged at one side of the air inlet chamber (4); the air flow direction in the first expansion chamber (102) is arranged at an angle to the air flow direction in the air inlet chamber (4); the first expansion chamber (102) is in the shape of a curved tube and is connected between the air inlet chamber (4) and the first expansion chamber (102).

12. The sound-absorbing assembly according to claim 9, characterized in that: Also includes: An air suction chamber (9) is disposed in the housing (1) and is connected to an air intake end of the air intake chamber (4); The fan (8) is arranged in the air suction cavity (9) and is capable of delivering air toward the air inlet end of the air inlet cavity (4).

13. A sweeping robot, characterized in that: include: A main body, wherein a dust collection box is provided in the main body; The silencer assembly according to any one of claims 1 to 12, wherein the air inlet end of the silencer assembly is connected to the dust collecting box.

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