U.S. patent application number 16/771644 was filed with the patent office on 2021-06-17 for vacuum pump exhaust pipe muffler and refrigerator having same.
The applicant listed for this patent is QINGDAO HAIER CO., LTD.. Invention is credited to JIANQUAN CHEN, ENPIN XIA, CHUN YANG, HAO ZHANG.
Application Number | 20210180581 16/771644 |
Document ID | / |
Family ID | 1000005476839 |
Filed Date | 2021-06-17 |
United States Patent
Application |
20210180581 |
Kind Code |
A1 |
YANG; CHUN ; et al. |
June 17, 2021 |
VACUUM PUMP EXHAUST PIPE MUFFLER AND REFRIGERATOR HAVING SAME
Abstract
A muffler comprising a hollow cavity enclosed by a first bottom
surface, a second bottom surface and a side wall, the side wall
connects the first bottom surface with the second bottom surface,
an air inlet at one end of the hollow cavity and an air outlet at
the other end of the hollow cavity; the cavity is divided into a
plurality of chambers in an axial direction, the chambers comprise
a first chamber adjacent to the first bottom surface, a second
chamber adjacent to the second bottom surface and an intermediate
chamber located between the first chamber and the second chamber,
the air inlet is in gas communication with the intermediate
chamber, and the air outlet is in gas communication with the first
chamber.
Inventors: |
YANG; CHUN; (Qingdao City,
Shandong Province, CN) ; CHEN; JIANQUAN; (Qingdao
City, Shandong Province, CN) ; ZHANG; HAO; (Qingdao
City, Shandong Province, CN) ; XIA; ENPIN; (Qingdao
City, Shandong Province, CN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
QINGDAO HAIER CO., LTD. |
Qingdao City, Shandong Province |
|
CN |
|
|
Family ID: |
1000005476839 |
Appl. No.: |
16/771644 |
Filed: |
December 7, 2018 |
PCT Filed: |
December 7, 2018 |
PCT NO: |
PCT/CN2018/119773 |
371 Date: |
June 10, 2020 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F25D 2317/0681 20130101;
F25D 17/062 20130101; F04B 39/0061 20130101 |
International
Class: |
F04B 39/00 20060101
F04B039/00; F25D 17/06 20060101 F25D017/06 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 11, 2017 |
CN |
201711311262.X |
Claims
1. A muffler comprising: a hollow cavity enclosed by a first bottom
surface, a second bottom surface and a side wall, the side wall
connects the first bottom surface with the second bottom surface;
an air inlet at one end of the muffler and an air outlet at the
other end of the muffler; the cavity is divided into a plurality of
chambers in an axial direction, the chambers comprise a first
chamber adjacent to the first bottom surface, a second chamber
adjacent to the second bottom surface and an intermediate chamber
located between the first chamber and the second chamber, the air
inlet is in gas communication with the intermediate chamber, the
intermediate chamber is in gas communication with the second
chamber, the first chamber is in gas communication with the second
chamber, and the air outlet is in gas communication with the first
chamber.
2. The muffler according to claim 1, wherein at least part of the
chambers has different volumes.
3. The muffler according to claim 1, wherein further comprises a
first duct, a second duct, a third duct and a fourth duct, the
first duct is communicated with the air inlet and the intermediate
chamber, the second duct is communicated with the intermediate
chamber and the second cavity, the third duct is communicated with
the first chamber and the second chamber, and the fourth duct is
communicated with the first chamber and the air outlet.
4. The muffler according to claim 3, wherein the first duct, the
second duct, the third duct and the fourth duct are arranged in
turn in an air path direction.
5. The muffler according to claim 1, wherein there is at least one
the intermediate chamber.
6. A muffler comprising a housing, wherein the housing is enclosed
to form a hollow cavity, an air inlet is arranged at a proximal end
of the housing, an air outlet is arranged at a distal end of the
housing, the cavity is divided into a plurality of chambers from
the proximal end to the distal end, the chambers comprise a first
chamber positioned relatively adjacent to the proximal end, a
second chamber positioned relatively adjacent to the distal end and
an intermediate chamber located between the first chamber and the
second chamber, the air inlet is in gas communication with the
intermediate chamber, the intermediate chamber is in gas
communication with the second chamber, the first chamber is in gas
communication with the second chamber, and the air outlet is in gas
communication with the first chamber.
7. The muffler according to claim 6, wherein at least part of the
chambers has different volumes.
8. The muffler according to claim 6, wherein further comprising a
first duct, a second duct, a third duct and a fourth duct, the
first duct is communicated with the air inlet and the intermediate
chamber, the second duct is communicated with the intermediate
chamber and the second cavity, the third duct is communicated with
the first chamber and the second chamber, and the fourth duct is
communicated with the first chamber and the air outlet.
9. The muffler according to claim 3, wherein the first duct, the
second duct, the third duct and the fourth duct are arranged in
turn in an air path direction.
10. A refrigerator comprising a sealed box receiving a vacuum pump,
wherein the refrigerator further comprises the muffler according to
claim 1, and the vacuum pump is connected with the muffler.
Description
[0001] This application claims the priority of Chinese patent
application, the filing date of which is Dec. 11, 2017, the
application number is 201711311262.X, and the title of invention is
"vacuum pump exhaust pipe muffler and refrigerator having same",
the entire contents of which are incorporated herein by reference
in its entirety.
TECHNICAL FIELD
[0002] The present invention relates to the technical field of
noise reduction of refrigeration apparatus, and specifically to a
muffler for reducing noise of a vacuum pump.
BACKGROUND
[0003] Freshness of food in a refrigerator is closely related to
temperature, humidity and gas environment, wherein oxygen is an
important factor causing spoilage, deterioration and bacteria
multiplication of the food. A preservation period of the food may
be significantly prolonged by pumping oxygen in the compartment to
control a nitrogen-to-oxygen ratio of the refrigerator.
[0004] Oxygen may be pumped out from a specific space via a vacuum
pump, and discharged outside the refrigerator. However, when gas,
as a medium for conducting a sound, conducts noise in the
refrigerator to an external space of the refrigerator during the
discharge, thereby causing noise interference.
SUMMARY
[0005] An object of the present invention is to provide a muffler
to solve the problem of noise output of a vacuum pump.
[0006] To achieve the object, the present invention provides a
muffler comprising a hollow cavity enclosed by a first bottom
surface, a second bottom surface and a side wall, the side wall
connects the first bottom surface with the second bottom surface;
an air inlet at one end of the muffler and an air outlet at the
other end of the muffler; the cavity is divided into a plurality of
chambers in an axial direction, the chambers comprise a first
chamber adjacent to the first bottom surface, a second chamber
adjacent to the second bottom surface and an intermediate chamber
located between the first chamber and the second chamber, the air
inlet is in gas communication with the intermediate chamber, the
intermediate chamber is in gas communication with the second
chamber, the first chamber is in gas communication with the second
chamber, and the air outlet is in gas communication with the first
chamber.
[0007] A further improvement as an embodiment of the present
invention, at least part of the chambers has different volumes.
[0008] A further improvement as an embodiment of the present
invention, the muffler further comprises a first duct, a second
duct, a third duct and a fourth duct, the first duct is
communicated with the air inlet and the intermediate chamber, the
second duct is communicated with the intermediate chamber and the
second cavity, the third duct is communicated with the first
chamber and the second chamber, and the fourth duct is communicated
with the first chamber and the air outlet.
[0009] A further improvement as an embodiment of the present
invention, the first duct, the second duct, the third duct and the
fourth duct are configured to be arranged in turn in an air path
direction.
[0010] A further improvement as an embodiment of the present
invention, there is at least one the intermediate chamber.
[0011] To achieve the object, the present invention provides a
muffler comprising a housing, wherein the housing is enclosed to
form a hollow cavity, an air inlet is arranged at a proximal end of
the housing, an air outlet is arranged at a distal end of the
housing, the cavity is divided into a plurality of chambers from
the proximal end to the distal end, the chambers comprise a first
chamber positioned relatively adjacent to the proximal end, a
second chamber positioned relatively adjacent to the distal end and
an intermediate chamber located between the first chamber and the
second chamber, the air inlet is in gas communication with the
intermediate chamber, the intermediate chamber is in gas
communication with the second chamber, the first chamber is in gas
communication with the second chamber, and the air outlet is in gas
communication with the first chamber.
[0012] A further improvement as an embodiment of the present
invention, at least part of the chambers has different volumes.
[0013] A further improvement as an embodiment of the present
invention, the muffler further comprises a first duct, a second
duct, a third duct and a fourth duct, the first duct is
communicated with the air inlet and the intermediate chamber, the
second duct is communicated with the intermediate chamber and the
second cavity, the third duct is communicated with the first
chamber and the second chamber, and the fourth duct is communicated
with the first chamber and the air outlet.
[0014] A further improvement as an embodiment of the present
invention, the first duct, the second duct, the third duct and the
fourth duct are configured to be arranged in turn in an air path
direction.
[0015] To achieve the project, the present invention provides a
refrigerator comprising a sealed box receiving a vacuum pump,
wherein the refrigerator further comprises the muffler as above,
and the vacuum pump is connected with the muffler.
[0016] As compared with the prior art, a refrigerator vacuum pump
muffler provided by the present invention realizes the attenuation
of sound waves by the design with multiple cavities and
cyclically-arranged ducts, reduces the sound energy, and prevents
the noise of the vacuum pump and a box from being conducted outside
the box.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 is a schematic structural diagram of a sealed box
according to an embodiment of the present invention;
[0018] FIG. 2 is a schematic diagram of components inside and
outside a sealed box according to an embodiment of the present
invention;
[0019] FIG. 3 is a top view of a sealed box according to an
embodiment of the present invention;
[0020] FIG. 4 is an exploded schematic view of a sealed box
according to an embodiment of the present invention;
[0021] FIG. 5 is a front view of a sealed box according to an
embodiment of the present invention;
[0022] FIG. 6 is a top view of a seal in an embodiment of the
present invention;
[0023] FIG. 7 is a schematic structural diagram of a seal in an
embodiment of the present invention;
[0024] FIG. 8 is a top view of a lower sealing body in an
embodiment of the present invention;
[0025] FIG. 9 is a schematic diagram of mounting an upper sealing
body and a metal plate in an embodiment of the present
invention;
[0026] FIG. 10 is a schematic structural diagram of a lower sealing
body in an embodiment of the present invention;
[0027] FIG. 11 is an exploded view of FIG. 10;
[0028] FIG. 12 is a perspective view of a muffler in an embodiment
of the present invention;
[0029] FIG. 13 is a perspective view of a muffler in another
embodiment of the present invention;
[0030] FIG. 14 is a schematic structural diagram of a vacuum pump
and a muffler in a further embodiment of the present invention;
[0031] FIG. 15 is a schematic structural diagram of a muffler in a
further embodiment of the present invention;
[0032] FIG. 16 is a perspective view of a muffler in a further
embodiment of the present invention;
[0033] FIG. 17 is a schematic longitudinal sectional view of a
muffler in a further embodiment of the present invention.
DETAILED DESCRIPTION
[0034] The present invention will be described in detail in
conjunction with specific embodiments shown in the figures.
However, these embodiments are not limited to the present
invention. Variations in terms of structure, method or function
made by those having ordinary skill in the art according to these
embodiments are all comprised in the scope of the present
invention.
[0035] Terms indicating positions and directions described in the
present invention all take a vacuum pump as a reference. An end
close to the vacuum pump is a proximal end, and an end away from
the vacuum pump is a distal end.
[0036] Referring to FIG. 1 through FIG. 3, in an embodiment of the
present invention, a vacuum pump 100 is received in a sealed box
200, and communicated with ambient air through an air inlet pipe
210 and an air outlet pipe 220. A proximal end of the air inlet
pipe 210 is communicated with an air intake line of the vacuum pump
100, and a distal end is communicated with a fresh-keeping space in
the refrigerator compartment (not shown); a proximal end of the air
outlet pipe 220 is communicated with an air exhaust line of the
vacuum pump 100, and a distal end extends towards outside the
sealed box 200. The sealed box 200 blocks air communication between
the vacuum pump 100 and an installation environment, and achieves
an effect of sound insulation. The fresh-keeping space may be
either an independent compartment or a closed or semi-closed space
located in a portion of the refrigerator compartment.
[0037] The sealed box 200 comprises an upper sealing body 230 and a
lower sealing body 240. The upper sealing body 230 comprises a top
wall and side walls which are integrally formed and jointly define
a receiving cavity with a lower end opening. The lower sealing body
240 comprises a bottom wall and side walls which are integrally
formed and jointly define a receiving cavity with an upper end
opening. The opening of the upper sealing body 230 and the opening
of the lower sealing body 240 match each other, and snap fit each
other to form a receiving space of the vacuum pump 100.
[0038] Preferably, the upper sealing body 230 and the lower sealing
body 240 are made of plastic.
[0039] Referring to FIG. 4, a seal is provided between the upper
sealing body 230 and the lower sealing body 240. A first groove is
formed at a lower edge of the side walls of the upper sealing body
230, a second groove is formed at an upper edge of the side walls
of the lower sealing body 240, and the first groove matches with
the second groove to form a mounting groove for a gasket ring 250.
In this way, the airtightness can be ensured after the upper
sealing body 230 and the lower sealing body 240 are snap fitted,
and sound can be prevented from being transmitted outside through a
splicing gap of the sealed box 200. The gasket ring 250 is
ring-shaped and has a circular cross-section. The gasket ring 250
is made of an elastic material, and has a mounting tension amount
2-5% when embedded in the mounting groove. When the upper sealing
body 230 and the lower sealing body 240 are snap-fitted, a pressure
is applied to the gasket ring 250 to form a 20-30% compression
amount, thereby ensuring the sealing effect.
[0040] FIG. 4 and FIG. 5 show that a notch portion 251 is provided
at where the upper sealing body 230 and the lower sealing body 240
are engaged, and allows a wire connected to the vacuum pump 100 to
pass through. In order to ensure the sealing performance of the
sealed box 200, a snap-fittable sealing ring 253 is provided at the
notch portion 251. The sealing ring 253 is made of an elastic
material and integrally formed with the gasket ring 250.
[0041] Referring to FIG. 6 and FIG. 7, the sealing ring 253 is
composed of two H-shaped members that are flexibly connected, and
the H-shaped members can be snap-fitted to each other to form a
mounted state that cooperates with the notch portion 251. The
H-shaped member has a first arm 2531 and a second arm 2532 parallel
to each other, and a connecting portion 2533 connecting the first
arm 2531 with the second arm 2532. The first arm 2531 and the
second arm 2532 can cooperate to clamp the side wall of the box
body at the edge of the notch portion 251 therebetween to prevent
the sealing ring 253 from falling off from the notch portion 251.
The connecting portion 2533 passes through the notch portion and
connects the first arm 2531 with the second arm 2532. The
connecting portion 2533 has a recessed arc-shaped surface. When the
H-shaped members are snap-fitted to each other, their arc-shaped
surfaces together enclose to form a hollow cavity to allow the wire
to pass therethrough.
[0042] In a case where a plurality of wires passes through the
notch portion 251, if the wires as a whole pass through the notch
portion 251, since the cross section of the wires is circular, a
gap formed between the wires will reduce the sealing performance.
In this case, the arc-shaped surface of the connecting portion 2533
may be wavy (not shown) to form a plurality of independent hollow
cavities in the mounted state to better seal the wires with a
circular cross-section.
[0043] Referring to FIG. 8, a plurality of metal plates 260 are
disposed in the sealed box 200, and the metal plates 260 are
disposed between the vacuum pump 100 and the side walls of the
sealed box 200. Since the metal plates 260 have a high density,
they can block transmission of sound therethrough and achieve an
effect of sound insulation and noise reduction.
[0044] Preferably, the metal plate 260 is an aluminum plate, a
steel plate, or a galvanized plate.
[0045] Referring to FIG. 8 and FIG. 9, in an embodiment of the
present invention, there are two metal plates 260 which are
respectively attached to two opposite walls of the sealed box 200.
The lower sealing body 240 and the upper sealing body 230 are
respectively provided with a limiting structure to secure the metal
plates 260a and 260b.
[0046] FIG. 8 shows that the bottom wall of the lower sealing body
240 is provided with a first rib 242 being parallel to a side wall
241 and spaced apart a distance d, and a second rib 244 being
parallel to a side wall 243 and spaced apart a distance D, wherein
the side wall 241 and the side wall 243 are opposed, d is the
thickness of the metal plate 260a, and D is the thickness of the
metal plate 260b. The spacing between the first rib 242 and the
side wall 241 forms a limiting groove that limits the horizontal
displacement of the metal plate 260a, and the spacing between the
second rib 244 and the side wall 243 forms a limiting groove that
limits the horizontal displacement of the metal plate 260b.
[0047] Referring to FIG. 8 and FIG. 10, the lower sealing body 240
is further provided with a plurality of guide grooves 245. The
guide grooves 245 extend in a vertical direction and the extension
direction is consistent with the insertion direction installing the
metal plates 260. The guide grooves 245 guide the metal plates 260
to be mounted to preset positions.
[0048] FIG. 9 shows that the upper sealing body 230 is provided
with a plurality of resisting members 231. When the upper sealing
body 230 and the lower sealing body 240 are snap-fitted, the
resisting member 231 against the top of the metal plate 260. A
stepped portion 2311 is provided at an end of the resisting member
231 which is in contact with the metal plate 260. The stepped
portion 2311 cooperates with the side walls of the upper sealing
body 230 to form an inverted U-shaped space to accommodate the top
of the metal plate 260. The top surface of the stepped portion 2311
against the top surface of the metal plate 260 and limits the
displacement of the metal plate 260 in the vertical direction. The
sides of the stepped portion abut against the sides of the metal
plate 260 and limit the displacement of the metal plate 260 in the
horizontal direction.
[0049] The metal plate 260 is disposed close to the side wall of
the sealed box 200. The vibration of the vacuum pump 100 might
cause resonance of the metal plate 260 to form new noise which is
conducted externally through the walls of the sealed box 200. The
above limiting structures strictly limit the position of the metal
plates 260 to avoid resonating and generating noise.
[0050] In an embodiment of the present invention, a notch portion
246 is disposed on one of the upper sealing body 230 and lower
sealing body 240, or on an engagement portion of the upper sealing
body 230 and lower sealing body 240, to allow an air pipe assembly
to pass therethrough.
[0051] FIG. 10 and FIG. 11 exemplarily show a case where the notch
portion 246 is provided on the lower sealing body 240. The notch
portion 246 is provided on a side wall of the lower sealing body
240 close to the upper edge, and a groove is provided at peripheral
edge of the notch portion 246 to receive a sealing unit 270 to
ensure the airtightness of the sealed box 200. The sealing unit 270
has an annular structure made of an elastic material.
[0052] The air pipe assembly comprises an air inlet pipe 210, an
air outlet pipe 220 and a base plate that are integrally formed.
The air inlet pipe 210 and the air outlet pipe 220 are disposed
through the base plate, and an outer edge of the base plate matches
the shape of the notch portion 246. A groove is provided on the
outer edge of the base plate to mate with a flange on the periphery
of the notch portion 246, the mating of the groove and the flange
can clamp and secure the base plate to the notch portion, and the
sealing unit 270 is embedded at a gap between the groove and the
flange.
[0053] The space of the cavity for receiving the vacuum pump 100 is
compact and does not facilitate the operation of connecting and
passing the air pipe line. It is possible to, by setting the air
pipe assembly as an embedded mounting structure, conveniently embed
and secure the air pipe assembly in the notch portion 246 after the
air pipe assembly is connected with the vacuum pump 100, and then
snap-fit the upper sealing body 230 and the lower sealing body 240
to complete the assembling.
[0054] The gas from the air outlet pipe 220 is exhausted to the
outside of the refrigerator after being silenced. Referring to FIG.
1 and FIG. 12, in an embodiment of the present invention, the
vacuum pump 100 is connected to the muffler 300 through the air
outlet pipe 220. The muffler 300 comprises a housing. The housing
is enclosed jointly by a first bottom surface 310 at a proximal
end, a second bottom surface 320 at a distal end and a side wall
330 connecting the first bottom surface 310 with the second bottom
surface 320 to form a cylindrical hollow cavity. The muffler 300 is
provided at the proximal end with an air inlet 340 connected to the
air outlet pipe 220, and provided with an air outlet 350 at the
distal end. The interior of the cavity is divided into several
chambers in an axial direction, the axial direction is the
direction from the air inlet 340 to the air outlet 350, and at
least part of the chambers has different volumes to correspondingly
remove sounds at different frequency bands. Exemplarily, the
volumes of respective chambers gradually decrease in the axial
direction.
[0055] Preferably, there are three chambers, which are a first
chamber 361, an intermediate chamber 362 and a second chamber 363
in turn from the proximal end to the distal end. The first chamber
361 is adjacent to the first bottom surface 310, the second chamber
363 is adjacent to the second bottom surface 320, and the
intermediate cavity 362 is located between the first chamber 361
and the second chamber 363. A first duct 371 is communicated with
the air inlet 340 and the intermediate chamber 362, a second duct
372 is communicated with the intermediate chamber 362 and the
second chamber 363, a third duct 373 is communicated with the first
chamber 361 and the second chamber 363, and a fourth duct 374 is
communicated with the first chamber 361 and the air outlet 350.
[0056] There may be a plurality of intermediate chambers 362.
[0057] The shape of the housing of the muffler is not limited to a
cylindrical shape, and may be set to a rectangular parallelepiped
shape or an irregular shape.
[0058] Sound waves from the vacuum pump 100 pass through the first
duct 371, the second duct 372, the third duct 373 and the fourth
duct 374 in turn along with the airflow, and are reflected and
refracted in turn in the intermediate chamber 362, the second
chamber 363 and the first chamber 361 which have different volumes,
and their energy is gradually dissipated. The muffling frequencies
corresponding to the first chamber 361, the intermediate chamber
362 and the second chamber 363 are a low frequency, a medium
frequency and a high frequency. In addition, the first duct 371,
the second duct 372, the third duct 373 and the fourth duct 374 are
provided with narrow inner diameters, so that partial energy of the
sound waves is converted into thermal energy and dissipated when
the sound waves pass through the ducts.
[0059] The muffler is arranged in a way that the sound waves travel
in a path as long as possible in the muffler to reduce the energy
and are reflected and refracted in different chambers, and a better
muffling effect is achieved with a smaller muffler axial
distance.
[0060] Referring to FIG. 13, in a further embodiment of the present
invention, the muffler 400 comprises a housing. The housing is
enclosed jointly by a first bottom surface 410 at a proximal end, a
second bottom surface 420 at a distal end, and a side wall 430
connecting the first bottom surface 410 with the second bottom
surface 420 to form a cylindrical hollow cavity. A single chamber
is formed in the cavity. The muffler 400 is provided with an air
inlet 440 connected to the air outlet pipe 220 at the proximal end,
and an air outlet 450 provided at the distal end. A first duct 471
is communicated with the air inlet 440 and the chamber, and a
distal end of the first duct 471 is adjacent to the second bottom
surface 420. A second duct 472 is communicated with the chamber and
the air outlet 450, and a proximal end of the second duct 472 is
adjacent to the first bottom surface 420.
[0061] The sound waves are reflected and refracted in the chamber,
and the energy is gradually dissipated. The length of the first
duct 471 and the second duct 472 is a quarter of a wavelength of a
target audio to specifically eliminate the sound of the target
audio. Preferably, a frequency of the target audio is 1000 Hz.
[0062] The first duct 471 and the second duct 472 are provided with
narrow inner diameters, so that partial energy of the sound waves
is converted into thermal energy and dissipated when the sound
waves pass through the ducts.
[0063] In the noise generated by the vacuum pump 100 and conducted
via gas, the high-frequency noise cannot be heard by human ears,
and the noise causing interference to the user is mainly
low-frequency noise. The present embodiment may purposefully
eliminate low-frequency noise and make the structure of the muffler
simpler.
[0064] Referring to FIG. 14 and FIG. 15, in a further embodiment of
the present invention, the muffler 500 is disposed inside the
sealed box 200, and connects the exhaust line of the vacuum pump
100 and the air outlet pipe 220. The muffler 500 comprises a
housing, and the housing is enclosed to form a hollow cavity for
refraction and reflection of sound waves. The hollow cavity
comprises a cylindrical chamber 510 and a rectangular
parallelepiped chamber 520. One of bottom surfaces of the
cylindrical chamber 510 is connected to one surface 521 of the
rectangular parallelepiped chamber 520. The cylindrical chamber 510
is communicated with the interior of the rectangular parallelepiped
chamber 520.
[0065] The diameter of the bottom surface of the cylindrical
chamber 510 is less than or equal to a length of a side of a
connecting surface 521 of the rectangular parallelepiped chamber
520.
[0066] The cylinder chamber 510 of the muffler 500 is provided with
an air inlet 540 and an air outlet 550, and the air inlet 540 and
the air outlet 550 are arranged at an angle so that the gas
entering the hollow cavity reaches the outlet through reflected and
refracted. During the process, the energy loses to achieve the
muffling purpose.
[0067] Preferably, the air inlet 540 is disposed on the bottom
surface 511 of the cylindrical chamber 510, and the air outlet 550
is disposed on a side of the cylindrical chamber 510.
[0068] The inner diameters of the air inlet 540 and the air outlet
550 are the same, so that the pressures at the two ports are
balanced.
[0069] In the present embodiment, through the change of the shape
of the hollow cavity, the sound waves are enabled to be reflected
and refracted irregularly, and the energy is dissipated.
[0070] Referring to FIG. 16 and FIG. 17, in a further embodiment of
the present invention, a muffler 600 comprises a housing, and the
housing is enclosed to form a hollow cavity. The muffler 600 is
provided with an air inlet 640 at a proximal end and an air outlet
650 at a distal end. The air inlet 640 and the air outlet 650 are
communicated by a duct 670 provided in the housing. The duct 670
and the housing form a sleeve structure. The duct 670 is filled
with a medium to absorb the vibrational energy of the sound waves
and weaken the sound intensity. Furthermore, the medium is silencer
cotton.
[0071] A plurality of through holes 680 are defined on the side
wall of the duct 670, so that the duct 670 can implement
communication with the cavity. The through holes 680 are
distributed spaced apart in a circumferential direction of the
sidewall of the duct 670, that is, the duct 670 defines through
holes in a plurality of directions.
[0072] Preferably, the housing is enclosed jointly by a first
bottom surface 610 at a proximal end, a second bottom surface 620
at a distal end, and a side wall 630 connecting the first bottom
surface 610 with the second bottom surface 620 to form a
cylindrical hollow cavity. The first bottom surface 610 is provided
with an air inlet 640, and the second bottom surface 620 is
provided with an air outlet 640.
[0073] Preferably, a diameter of the through holes is less than 1
mm.
[0074] Preferably, the cavity enclosed by the housing is divided
into several chambers arranged from the proximal end to the distal
end.
[0075] The sound waves from the vacuum pump 100 enter the duct 670
from the air inlet 640, and reach the air outlet 650 after being
silenced by the medium. The sound waves at a specific frequency are
attenuated and the sound intensity is weakened. During this
process, partial sound waves, being diffracted by the through holes
680, enter the cavity, and are further attenuated after being
refracted and reflected in the cavity.
[0076] The muffler is arranged in a way that the sound intensity is
reduced through multiple channels by combining medium sound
reduction with cavity sound reduction and be employing small holes
to implement sound wave diffraction.
[0077] It should be understood that although the description is
described according to the embodiments, not every embodiment only
comprises one independent technical solution, that such a
description manner is only for the sake of clarity, that those
skilled in the art should take the description as an integral part,
and that the technical solutions in the embodiments may be suitably
combined to form other embodiments understandable by those skilled
in the art.
[0078] The detailed descriptions set forth above are merely
specific illustrations of feasible embodiments of the present
invention, and are not intended to limit the scope of protection of
the present invention. All equivalent embodiments or modifications
that do not depart from the art spirit of the present invention
should fall within the scope of protection of the present
invention.
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