U.S. patent application number 12/450000 was filed with the patent office on 2010-04-15 for silencer for pneumatic device.
Invention is credited to Ho-Young Cho.
Application Number | 20100089689 12/450000 |
Document ID | / |
Family ID | 38736579 |
Filed Date | 2010-04-15 |
United States Patent
Application |
20100089689 |
Kind Code |
A1 |
Cho; Ho-Young |
April 15, 2010 |
SILENCER FOR PNEUMATIC DEVICE
Abstract
The present invention provides a silencer, which is coupled to a
pneumatic device to reduce noise. The silencer (10) of the present
invention has a double pipe structure, which includes an inner
casing (11), which is coupled to an outlet of the pneumatic device,
and an outer casing (12), which is coaxially provided around the
inner casing (11). A space (18) is defined between the inner casing
and the outer casing. The space communicates with an air guide hole
(15), which is formed in one end of the inner casing. Furthermore,
an acoustical absorbent (22) is provided in the space (18).
Preferably, the acoustical absorbent has a spiral shape. Thus,
compressed air, which has passed through the pneumatic device,
passes through the acoustical absorbent of the silencer. At this
time, almost all noise is absorbed by the acoustical absorbent.
Inventors: |
Cho; Ho-Young; (Seoul,
KR) |
Correspondence
Address: |
ROBERT C. KLINGER;LAW OFFICE OF ROBERT C. KLINGER
2591 DALLAS PARKWAY, SUITE 300
FRISCO
TX
75034
US
|
Family ID: |
38736579 |
Appl. No.: |
12/450000 |
Filed: |
January 29, 2008 |
PCT Filed: |
January 29, 2008 |
PCT NO: |
PCT/KR2008/000528 |
371 Date: |
September 4, 2009 |
Current U.S.
Class: |
181/230 |
Current CPC
Class: |
F16L 55/02781 20130101;
F04C 2270/13 20130101; F04C 29/06 20130101; F16L 55/0336 20130101;
F16L 55/02772 20130101; F16L 55/0279 20130101 |
Class at
Publication: |
181/230 |
International
Class: |
F01N 1/08 20060101
F01N001/08 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 8, 2007 |
KR |
10-20070022787 |
Claims
1. A silencer for a pneumatic device, comprising: an inner casing
opened at a first end thereof and closed at a second end thereof,
with transverse air guide means formed in the open end or the
closed end of the inner casing, the air guide means communicating
with an outlet in the pneumatic device; an outer casing provided
around the inner casing coaxially such that a space for
communicating with the air guide means is defined between the inner
casing and the outer casing, with an exhaust hole formed in the
outer casing at a position opposite the air guide means, the
exhaust hole communicating with the space; and an acoustical
absorbent provided in the space defined between the inner casing
and the outer casing.
2. The silencer for the pneumatic device according to claim 1,
wherein the acoustical absorbent has a spiral shape, so that the
space forms a spiral passage.
3. The silencer for the pneumatic device according to claim 1,
wherein the air guide means comprises at least one hole.
4. The silencer for the pneumatic device according to claim 1,
wherein the outer casing is supported at opposite ends thereof by
respective flanges, which are provided around the open end and the
closed end of the inner casing, respectively.
5. The silencer for the pneumatic device according to claim 1,
wherein the exhaust hole is formed through a sidewall of the outer
casing.
6. The silencer for the pneumatic device according to claim 4,
wherein the exhaust hole is formed in the flange disposed opposite
the air guide means.
7. The silencer for the pneumatic device according to claim 5,
wherein orientation of the exhaust hole is changed by rotating the
outer casing.
8. The silencer for the pneumatic device according to claim 1,
wherein a tool holding part is provided on the closed end of the
inner casing, so that the silencer is coupled to or removed from
the pneumatic device by rotating the tool holding part.
Description
TECHNICAL FIELD
[0001] The present invention relates to a silencer, which is
coupled to an outlet of a pneumatic device, which is actuated using
compressed air, so as to reduce noise.
BACKGROUND ART
[0002] Generally, the term `pneumatic device` is a general term for
devices that are actuated using compressed air as drive force, for
example, including a vacuum pump, a vacuum cylinder, a vacuum
conveyor, a vacuum motor, etc.
The above-mentioned devices have an air inlet and an air outlet
therein. In such a pneumatic device, because excessive noise is
generated when compressed air passes through the pneumatic device
and is exhausted outside through the outlet, a silencer for
reducing noise is required.
[0003] FIGS. 1 and 2 illustrate conventional silencers. The
silencer 1 of FIG. 1 includes a cylindrical body 2, which has a
plurality of through holes in the sidewall thereof, and a porous
acoustical absorbent 3, which is charged into the cylindrical body
2. An open end of the cylindrical body 2 is coupled to an outlet of
a pneumatic device. The silencer 4 of FIG. 2 includes a coupling
fitting 5, and an acoustical absorbent 6, which is fastened to the
fitting 5. The fitting 5 is coupled to an outlet of a pneumatic
device.
[0004] In these silencers, compressed air, which is output from the
pneumatic device, is exhausted outside the silencer via the
acoustical absorbent 3, 6 (refer to the arrows). In this process, a
noise source is absorbed by the acoustical absorbent 3, 6, so that
the generation of noise is reduced.
[0005] However, the conventional silencers 1 and 4 are problematic
in that an excessive amount of acoustical absorbent 3, 6 is
required, and in that, despite the use of an excessive amount of
acoustical absorbent, because the distance that noise passes
through the acoustical absorbent 3, 6 is relatively short, the
noise absorption effect is unsatisfactory.
Furthermore, the use of the acoustical absorbent 3, 6 induces an
increase in exhaust pressure, but the conventional techniques have
no means of mitigating this problem.
[0006] FIG. 3 illustrates a silencer 7, which was proposed
recently. The silencer 7 includes a pipe-shaped body 8, and a
cylindrical acoustical absorbent 9, which is provided on the inner
surface of the body 8. The silencer 7 has an advantage in that the
amount of acoustical absorbent 9 that is used can be reduced
compared to that of the prior silencer 1 or 4.
However, a relatively large portion of noise is directly exhausted
outside the silencer rather than being absorbed by the acoustical
absorbent 9 (see the arrows). Therefore, there is a problem in that
the noise absorption effect is very low.
DISCLOSURE
Technical Problem
[0007] Accordingly, the present invention has been made keeping in
mind the above problems occurring in the silencers according to the
conventional techniques, and an object of the present invention is
to provide a silencer which efficiently uses a relatively small
amount of acoustical absorbent.
Another object of the present invention is to provide a silencer in
which the lengths of the contact surface of the acoustical
absorbent and the air passage can be maximized in the limited
length of the silencer. A further object of the present invention
is to provide a silencer which can vary the direction in which air
is exhausted outside the silencer.
TECHNICAL SOLUTION
[0008] In order to accomplish the above objects, the present
invention provides a silencer for a pneumatic device, including: an
inner casing open at a first end thereof and closed at a second end
thereof, with transverse air guide means formed in the open end or
the closed end of the inner casing, the air guide means
communicating with an outlet of the pneumatic device; an outer
casing provided coaxially around the inner casing such that a space
for communicating with the air guide means is defined between the
inner casing and the outer casing, with an exhaust hole formed in
the outer casing at a position opposite the air guide means, the
exhaust hole communicating with the space; and an acoustical
absorbent provided in the space defined between the inner casing
and the outer casing. Preferably, the acoustical absorbent has a
spiral shape.
[0009] With regard to the flow of air, compressed air, which is
output from the pneumatic device, is guided into the space defined
between the inner casing and the outer casing through the air guide
means of the silencer and, thereafter, it passes through the
acoustical absorbent and is exhausted outside the silencer through
the exhaust hole. In this process, noise is absorbed by the
acoustical absorbent, so that the generation of noise is markedly
reduced.
[0010] In the silencer of the present invention, a relatively small
amount of the acoustical absorbent is provided between the inner
and outer casings, which form a coaxial double pipe structure. The
acoustical absorbent is configured such that noise passes through
the acoustical absorbent in the longitudinal direction, thus
ensuring a superior noise absorption effect.
Particularly, because the acoustical absorbent has a spiral shape,
the length thereof is maximally extended, thus further increasing
the noise absorption effect. Furthermore, because the acoustical
absorbent defines a spiral passage, the exhaust pressure of
compressed air is markedly reduced. Meanwhile, in the silencer of
the present invention, which has the double pipe structure, the
direction in which compressed air is finally exhausted outside the
silencer can be changed by slightly rotating the outer casing.
ADVANTAGEOUS EFFECTS
[0011] The silencer according to the present invention includes an
inner casing and an outer casing, which has a space there between,
and an acoustical absorbent, which is provided in the space between
the inner and outer casings. The acoustical absorbent is configured
such that noise passes through the acoustical absorbent in the
longitudinal direction, thus ensuring a superior noise absorption
effect. Particularly, because the acoustical absorbent has a spiral
shape, the length thereof is maximally extended, thus further
increasing the noise absorption effect. Furthermore, because the
acoustical absorbent defines a spiral passage, the exhaust pressure
of compressed air is markedly reduced.
DESCRIPTION OF DRAWINGS
[0012] FIGS. 1, 2 and 3 are sectional views showing several
conventional silencers;
[0013] FIG. 4 is a perspective view of a silencer, according to a
first embodiment of the present invention;
[0014] FIG. 5 is an exploded perspective view of FIG. 4;
[0015] FIG. 6 is a sectional view of FIG. 4;
[0016] FIG. 7 is a perspective view of a silencer, according to a
second embodiment of the present invention; and
[0017] FIG. 8 is a view illustrating the operation of the silencer
according to the present invention.
DESCRIPTION OF THE ELEMENTS IN THE DRAWINGS
TABLE-US-00001 [0018] 10. silencer 11. inner casing 12. outer
casing 15. hole 16, 20. flange 18. space 19. exhaust hole 22.
acoustical absorbent 23. vacuum ejector
Best Model
[0019] The above and other objects, features and advantages of the
present invention will be more clearly understood from the
following detailed description, taken in conjunction with the
accompanying drawings.
[0020] Referring to FIGS. 4 through 6, a silencer according to a
first embodiment of the present invention is designated by the
reference numeral 10. The silencer 10 includes an inner casing 11,
which has a hollow structure, and an outer casing 12, which is
coaxially provided around the inner casing 11, thus forming a
double pipe structure. The inner casing 11 has a cylindrical shape,
which is open at a first end 13 thereof and closed at a second end
14 thereof. Holes 15 serving as transverse air guide means are
formed in the inner casing adjacent to the closed end 14.
Preferably, at least two holes 15 are formed around the closed end
14. Meanwhile, as in the second embodiment of the present
invention, air guide holes 15 may be formed around the open end 13
in the inner casing 11 (see, FIG. 7).
[0021] A flange 16 for supporting the outer casing 12, which is
coaxially provided around the inner casing 11, and an external
threaded part 17 for enabling the silencer 10 to be coupled to a
pneumatic device are provided around the open end 13 of the inner
casing 11. The external threaded part 17 is coupled to or separated
from the pneumatic device by rotating a tool holding part 14a,
which is provided on the closed end 14.
[0022] The outer casing 12 is coaxially provided around the inner
casing 11 such that a space 18 is defined between the inner casing
11 and the outer casing 12 and communicates with the holes 15. Of
course, the inner diameter of the outer casing 12 is greater than
the outer diameter of the inner casing 11. An exhaust hole 19,
which communicates with the space 18, is formed in a first end of
the outer casing 12, which is opposite the air guide means 15.
As in the second embodiment, the exhaust hole 19 may be formed in
the flange 16 or 20 (see, FIG. 70).
[0023] The outer casing 12 is supported at the first end thereof by
the flange 16 of the inner casing 11, and is supported at a second
end thereof by the flange 20, which is provided around the closed
end 14 of the inner casing 11.
The flange 20 is supported by a retainer ring 21. Here, because the
outer casing 12 is not completely fixed to the flanges 16 and 20,
the orientation of the exhaust hole 19 may be varied by slightly
rotating the outer casing 12.
[0024] An acoustical absorbent 22 is installed in the space 18
defined between the outer casing 12 and the inner casing 11. The
acoustical absorbent 22 is made of material selected from among
porous material, fibrous material and other well-known kinds of
air-permeable material. Preferably, the acoustical absorbent 22 has
a spiral shape, so that a spiral passage is defined in the space
18.
[0025] FIG. 7 shows that the positions of the holes 15 and the
exhaust hole 19 can be varied from those of the first embodiment.
The general construction and operation of the embodiment of FIG. 7,
with the exception of the holes 15 and the exhaust hole 19, remains
the same as the first embodiment, therefore the same reference
numerals are used to designate the same or similar components as
those of the first embodiment, and further explanation of this
drawing is deemed unnecessary.
[0026] Referring to FIG. 8, the silencer 10 of the present
invention may be coupled to a vacuum ejector 23, which is a kind of
pneumatic device. The vacuum ejector 23 is a typical ejector, which
includes a nozzle body 24, having a rotationally symmetrical
structure, and through holes 26, which are formed through the
sidewall of the nozzle body 24 to communicate the nozzle body 24
with an enclosure space (not shown). Here, the present invention is
not limited to any special kind of pneumatic device or any
particular structure thereof.
[0027] The vacuum ejector 23 is mounted to a device which must be
exhausted, and is actuated using compressed air, which is drawn
thereinto and is exhausted therefrom through an outlet 25 at a high
speed, thus forming a negative pressure in the enclosure space.
With regard to the flow of air (refer to the directions of the
arrows), compressed air, which has passed through the vacuum
ejector 23, passes through the air guide holes 15 and the space 18
of the silencer 10 of the present invention and is thereafter
exhausted outside the silencer 10 through the exhaust hole 19.
[0028] At this time, noise generated by the ejector is absorbed by
the acoustical absorbent 22 while passing through the silencer, so
that the generation of noise is markedly reduced. Particularly, in
the present invention, because the acoustical absorbent 22 has a
spiral structure and thus forms a spiral passage, the length of the
acoustical absorbent 22 is maximized, so that the noise reduction
effect can be markedly enhanced.
Furthermore, the present invention can solve the problem with the
conventional silencer, in which exhaust pressure increases due to
the use of the acoustical absorbent.
* * * * *