U.S. patent application number 12/342151 was filed with the patent office on 2009-07-02 for dryer having gas heater.
This patent application is currently assigned to DAEWOO ELECTRONICS CORPORATION. Invention is credited to Chang Hoo Kim.
Application Number | 20090165324 12/342151 |
Document ID | / |
Family ID | 40796409 |
Filed Date | 2009-07-02 |
United States Patent
Application |
20090165324 |
Kind Code |
A1 |
Kim; Chang Hoo |
July 2, 2009 |
DRYER HAVING GAS HEATER
Abstract
A dryer includes a nozzle communicated with a gas pipe for
supplying gas; a gas injection passage which is provided in the
nozzle and through which the gas is injected; and an air intake
passage provided in the nozzle so as to be communicated with the
gas injection passage, wherein a cross section of the gas injection
passage is smaller than a cross section of the air intake
passage.
Inventors: |
Kim; Chang Hoo; (Gyeyang-gu,
KR) |
Correspondence
Address: |
SCHMEISER, OLSEN & WATTS
22 CENTURY HILL DRIVE, SUITE 302
LATHAM
NY
12110
US
|
Assignee: |
DAEWOO ELECTRONICS
CORPORATION
SEOUL
KR
|
Family ID: |
40796409 |
Appl. No.: |
12/342151 |
Filed: |
December 23, 2008 |
Current U.S.
Class: |
34/132 ;
432/222 |
Current CPC
Class: |
D06F 58/263
20130101 |
Class at
Publication: |
34/132 ;
432/222 |
International
Class: |
D06F 58/04 20060101
D06F058/04; F28C 3/00 20060101 F28C003/00 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 27, 2007 |
KR |
10-2007-0139506 |
Claims
1. A dryer, comprising: a nozzle communicated with a gas pipe for
supplying gas; a gas injection passage which is provided in the
nozzle and through which the gas is injected; and an air intake
passage provided in the nozzle so as to be communicated with the
gas injection passage, wherein a cross section of the gas injection
passage is smaller than a cross section of the air intake
passage.
2. The dryer of claim 1, wherein a diameter of the gas injection
passage is smaller than a diameter of the air intake passage.
3. The dryer of claim 2, further comprising a fastening part
provided in the nozzle to mount the nozzle.
4. The dryer of claim 3, wherein the length of the fastening part
is greater than the diameter of the air intake passage.
5. The dryer of claim 3, wherein the nozzle includes a nozzle for a
first gas and a nozzle for a second gas.
6. The dryer of claim 5, wherein the nozzle for a first gas
includes a nozzle for Liquefied Petroleum Gas (LPG) and the nozzle
for a second gas includes a nozzle for Liquefied Natural Gas (LNG)
and the diameter of the gas injection passage of the LPG nozzle is
smaller than the diameter of the gas injection passage of the LNG
nozzle.
7. The dryer of claim 6, wherein the diameter of the air intake
passage of the LPG nozzle is smaller than the diameter of the air
intake passage of the LNG nozzle.
8. The dryer of claim 6, wherein, in the LPG nozzle, the diameter
of the gas injection passage is 1.2 to 1.6 mm and the diameter of
the air intake passage is 1.8 to 2.2 mm.
9. The dryer of claim 8, wherein the length of the fastening part
is 3.8 to 4.2 mm.
10. The dryer of claim 6, wherein, in the LNG nozzle, the diameter
of the gas injection passage is 1.8 to 2.2 mm and the diameter of
the air intake passage is 2.8 to 3.2 mm.
11. The dryer of claim 10, wherein the length of the fastening part
is 3.8 to 4.2 mm.
12. The dryer of claim 1, wherein the nozzle has a shape of a
polygonal prism and the air intake passage is formed on a face
which forms the polygon.
13. The dryer of claim 1, wherein the cross section of the gas
injection passage is the smallest of cross sections of the flow
path of the gas injection passage and the cross section of the air
intake passage is the smallest of cross sections of the flow path
of the air intake passage.
14. A dryer, comprising: a gas pipe for supplying gas; a valve to
which the gas pipe is connected; a nozzle provided in the valve; a
gas injection passage which is provided in the nozzle and through
which the gas is injected; an air intake passage provided in the
nozzle so as to be communicated with the gas injection passage; and
a fastening part provided in the nozzle to mount the nozzle in the
valve, wherein a diameter of the gas injection passage is smaller
than a diameter of the air intake passage.
15. The dryer of claim 14, wherein the nozzle includes a nozzle for
Liquefied Petroleum Gas (LPG) and a nozzle for Liquefied Natural
Gas (LNG) which are detachably mounted in the valve.
16. The dryer of claim 15, wherein the diameter of the gas
injection passage of the LPG nozzle is smaller than the diameter of
the gas injection passage of the LNG nozzle.
17. The dryer of claim 15, wherein the diameter of the air intake
passage of the LPG nozzle is smaller than the diameter of the air
intake passage of the LNG nozzle.
18. The dryer of claim 14, wherein the diameter of the gas
injection passage is the smallest of diameters of the flow path of
the gas injection passage and the diameter of the air intake
passage is the smallest of diameters of the flow path of the air
intake passage.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims priority to Korean patent
application number 10-2007-0139506, filed on Dec. 27, 2007, which
is incorporated by reference in its entirety.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to a dryer, and more
particularly, to a dryer having a gas heater which can prevent
incomplete combustion.
[0003] FIG. 1 is a structural view showing a flow path of a
conventional dryer and FIG. 2 is a partially broken perspective
view of the conventional dryer.
[0004] Referring to FIGS. 1 and 2, the conventional dryer includes
a cabinet 2 which forms an external appearance of the dryer and
provided with an opening formed in front thereof and through which
laundries to be dried are put into the dryer, a drum 12 which is
rotatably mounted inside the cabinet 2 to accommodate the laundries
to be dried and has opened front and rear portions for allowing air
to pass therethrough, a heater 18 which is disposed inside the
cabinet 2 to heat the air sucked into the cabinet 2, an intake duct
20 which guides the heated air passed through the heater 18 to the
rear of the drum 12, an exhaust unit 22 which exhausts the air
polluted by drying the laundries to the outside of the cabinet 2, a
blower fan (not shown) which is installed in the exhaust unit 22,
and a motor (not shown) and a belt 40 which drive the drum 12 and
the blow fan to be rotated.
[0005] A lifter 11 is mounted on an inner peripheral surface of the
drum 12 to lift up and drop the laundries to be dried. Also. the
exhaust unit 22 includes a lint duct 25 which receives the air from
the drum 12 to filter foreign substances from the air by a filter
24 mounted therein, a fan housing 26 which communicates with the
lint duct 25 and houses the blower fan and an exhaust duct 27 which
communicates with the fan housing 26 at one end thereof and extends
to the outside of the cabinet 2 at the other end.
[0006] Operation of the conventional dryer having the above
described structure will be described.
[0007] First, by operating the dryer after putting the laundries to
be dried into the drum 12 and closing a door (not shown), the motor
is driven to rotate the drum 12 and the blower fan and the heater
18 is operated together. At this time, as the drum 12 is rotated,
the laundries to be dried in the drum 12 are lifted up and dropped
by the lifter 11. External air is sucked in the heater 18 by a
blowing force generated upon the rotation of the blower fan, heated
to air with high temperature and low humidity and then discharged
to the inside of the drum 12 through the intake duct 20. The air
with high temperature and low humidity supplied to the inside of
the drum 12 is brought into direct contact with the laundries to
dry the laundries and changed to air with low temperature and high
humidity. While drying the laundries, the air is moved toward the
front of the drum 12 and then exhausted to the outside of the dryer
through the exhaust duct 27.
[0008] In the conventional dryer, since a heater heated by electric
energy is installed inside a pipe communicated with the intake
duct, it takes much time to heat the heater and it is difficult to
reduce the time and cost taken for the drying operation as the high
price electric energy is used as a heat source. Therefore, it is
required to improve the problems.
SUMMARY OF THE INVENTION
[0009] Embodiments of the present invention are directed to a dryer
having a gas heater which can prevent incomplete combustion of
gas.
[0010] Also, embodiments of the present invention are directed to a
dryer having a gas heater which can use various kinds of the
gas.
[0011] In one embodiment, a dryer includes a nozzle communicated
with a gas pipe for supplying gas; a gas injection passage which is
provided in the nozzle and through which the gas is injected; and
an air intake passage provided in the nozzle so as to be
communicated with the gas injection passage, wherein a cross
section of the gas injection passage is smaller than a cross
section of the air intake passage.
[0012] A diameter of the gas injection passage is smaller than a
diameter of the air intake passage.
[0013] The dryer may further include a fastening part provided in
the nozzle to mount the nozzle. The length of the fastening part is
greater than the diameter of the air intake passage. The nozzle
includes a nozzle for a first gas and a nozzle for a second gas.
The nozzle for a first gas includes a nozzle for Liquefied
Petroleum Gas (LPG) and the nozzle for a second gas includes a
nozzle for Liquefied Natural Gas (LNG) and the diameter of the gas
injection passage of the LPG nozzle is smaller than the diameter of
the gas injection passage of the LNG nozzle. Also, the diameter of
the air intake passage of the LPG nozzle is smaller than the
diameter of the air intake passage of the LNG nozzle. In the LPG
nozzle, the diameter of the gas injection passage is 1.2 to 1.6 mm
and the diameter of the air intake passage is 1.8 to 2.2 mm. The
length of the fastening part is 3.8 to 4.2 mm. Also, in the LNG
nozzle, the diameter of the gas injection passage is 1.8 to 2.2 mm
and the diameter of the air intake passage is 2.8 to 3.2 mm. The
length of the fastening part is 3.8 to 4.2 mm.
[0014] Preferably, the nozzle has a shape of a polygonal prism and
the air intake passage is formed on a face which forms the
polygon.
[0015] The cross section of the gas injection passage is the
smallest of cross sections of the flow path of the gas injection
passage and the cross section of the air intake passage is the
smallest of cross sections of the flow path of the air intake
passage.
[0016] In another embodiment, a dryer includes a gas pipe for
supplying gas; a valve to which the gas pipe is connected; a nozzle
provided in the valve; a gas injection passage which is provided in
the nozzle and through which the gas is injected; an air intake
passage provided in the nozzle so as to be communicated with the
gas injection passage; and a fastening part provided in the nozzle
to mount the nozzle in the valve, wherein a diameter of the gas
injection passage is smaller than a diameter of the air intake
passage.
[0017] Preferably, the nozzle includes a nozzle for Liquefied
Petroleum Gas (LPG) and a nozzle for Liquefied Natural Gas (LNG)
which are detachably mounted in the valve. The diameter of the gas
injection passage of the LPG nozzle is smaller than the diameter of
the gas injection passage of the LNG nozzle. The diameter of the
air intake passage of the LPG nozzle is smaller than the diameter
of the air intake passage of the LNG nozzle.
[0018] Preferably, the diameter of the gas injection passage is the
smallest of diameters of the flow path of the gas injection passage
and the diameter of the air intake passage is the smallest of
diameters of the flow path of the air intake passage.
[0019] According to the dryer having a gas heater of the present
invention, since the structure of the nozzle for injecting the gas
is improved and thus incomplete combustion is prevented, it is
possible to reduce foreign substances produced upon the incomplete
combustion an d save the amount of the gas taken to drive the
dryer.
[0020] Also, according to the dryer having a gas heater of the
present invention, since the gas heater is provided instead of an
electric heater, it is possible to shorten the time for heating the
heater.
[0021] Also, according to the dryer having a gas heater of the
present invention, since various kinds of gas can be used as a fuel
and it is possible to achieve a caloric value required for the dry
by simply controlling the gas injection passage and the air intake
passage, it is possible to reduce the time and cost taken to
manufacture the dryer.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] FIG. 1 is a structural view showing a flow path of a
conventional dryer.
[0023] FIG. 2 is a partially broken perspective view of the
conventional dryer.
[0024] FIG. 3 is a structural view illustrating a dryer having a
gas heater in accordance with an embodiment of the present
invention.
[0025] FIG. 4 is an exploded perspective view illustrating a gas
heater of the dryer in accordance with an embodiment of the present
invention.
[0026] FIG. 5 is a perspective view illustrating a nozzle of the
gas heater of the dryer in accordance with an embodiment of the
present invention.
[0027] FIG. 6 is a longitudinal sectional view illustrating the
nozzle of the gas heater of the dryer in accordance with an
embodiment of the present invention.
[0028] FIG. 7 is a perspective view illustrating a flame holder of
the gas heater of the dryer in accordance with an embodiment of the
present invention.
[0029] FIG. 8 is a plan view illustrating an intake flow path of
the dryer having a gas heater in accordance with an embodiment of
the present invention.
[0030] FIG. 9 is a side sectional view illustrating a circulation
flow path of the dryer having a gas heater in accordance with an
embodiment of the present invention.
[0031] FIG. 10 is a plan view illustrating an exhaust flow path of
the dryer having a gas heater in accordance with an embodiment of
the present invention.
[0032] FIG. 11 is a graph showing content of carbon monoxide in
exhaust gas of the dryer having a nozzle and a flame holder for
LPG.
[0033] FIG. 12 is a graph showing content of carbon monoxide in
exhaust gas of the dryer having a nozzle and a flame holder for
LNG.
DESCRIPTION OF SPECIFIC EMBODIMENTS
[0034] Hereinafter, an exemplary embodiment of the present
invention will be described with reference to accompanying
drawings. For convenience of description, a dryer having a gas
heater will be described by way of example. It should be noted that
the drawings are not to precise scale and may be exaggerated in
thickness of lines or size of components for the purpose of
convenience and clarity only. Furthermore, terms used herein are
defined in consideration of functions in the present invention and
can be changed according to the custom or intention of users or
operators. Thus, definition of such terms should be determined
according to overall disclosures set forth herein.
[0035] FIG. 3 is a structural view illustrating a dryer having a
gas heater in accordance with an embodiment of the present
invention; FIG. 4 is an exploded perspective view illustrating a
gas heater of the dryer in accordance with an embodiment of the
present invention; FIG. 5 is a perspective view illustrating a
nozzle of the gas heater of the dryer in accordance with an
embodiment of the present invention; FIG. 6 is a longitudinal
sectional view illustrating the nozzle of the gas heater of the
dryer in accordance with an embodiment of the present invention;
and FIG. 7 is a perspective view illustrating a flame holder of the
gas heater of the dryer in accordance with an embodiment of the
present invention.
[0036] Referring to FIGS. 3 to 7, a dryer having a gas heater in
accordance with an embodiment of the present invention includes a
cabinet 50 which is provided with an opening and discharge port 54,
a drum 60 in which laundries to be dried is accommodated, a lifter
60a which is mounted on an inner wall of the drum 60 to rotate the
laundries to be dried, an intake duct 70 which guides air to the
inside of the drum 60, a gas heater 100 installed in the intake
duct 70, an exhaust fan 82 (refer to FIG. 10) which is provided
between the drum 60 and the discharge port 54, an exhaust duct 80
which is provided between the exhaust fan 82 and the discharge port
54 and a driving motor 90 (refer to FIG. 10) which is connected
with a rotation shaft of the exhaust fan 82.
[0037] When power is applied to the driving motor 90, the exhaust
fan 82 is rotated to circulate air and the air flowed in the inside
of the cabinet 50 is heated while passing the gas heater 100 and
supplied to the inside of the drum 60 along the intake duct 70 to
dry or sterilize the laundries to be dried. After that, the air is
flowed along the exhaust duct 80 and exhausted to an outside
through the discharge port 54 of the cabinet 50.
[0038] The drum 60 is formed in a cylindrical shape with opened
front and rear portions. The front portion of the drum 60
corresponds to the opening of the cabinet 50 and the rear portion
is rotatably mounted to a support panel 62 which is formed with a
through hole part 62a. The intake duct 70 is installed in the
through hole part 62a. Also, a front panel 64 is installed between
the front end portion of the drum 60 and the opening of the cabinet
50 and is formed with an exhaust hole 64a at a lower end portion
thereof. A connection duct 84 extended toward the exhaust fan 82 is
installed in the exhaust hole 64a, and a housing (not shown) for
rotatably housing the exhaust fan 82 therein is installed between
the connection duct 84 and the exhaust duct 80.
[0039] The intake duct 70 is extended from the gas heater 100 to
the through hole part 62a. Therefore, the air flowed in form the
inside of the cabinet 50 is heated while passing through the heater
100 and moved to the upper side of the cabinet 50 along the intake
duct 70 to be flowed into the drum 60. At this time, a contact area
between the hot air and the laundries to be dried is increased as
the drum connected with the driving motor 90 by a belt (not
shown).
[0040] The heater 100 includes a gas pipe 130 for supplying the gas
to the inside of the cabinet 50, a valve 150 to which the gas pipe
130 is connected, a nozzle 140 provided in the valve 150, a mixing
pipe 120 placed corresponding to the nozzle 140 to mix the gas and
the air, an ignition plug 170 placed mounted in an outside of the
mixing pipe 120 to generate sparks, a guide duct 110 placed at the
outside of the mixing pipe 120 to guide the heated air, a bracket
160 which is provided on an inner wall of the cabinet 50 and on
which the gas pipe 130, the mixing pipe 120 and the guide duct 110
are mounted and a flame holder 180 placed between the mixing pipe
120 and the guide duct 110 to prevent that a flame produced by the
ignition plug 170 becomes larger than a predetermined size.
[0041] When the valve 150 is opened and the gas is supplied to the
mixing pipe 120 along the gas pipe 130, the gas is mixed with the
air inside the cabinet 50 to be injected to the outside of the
mixing pipe 120 and the flame is then produced by the sparks
generated in the ignition plug 170. Size and production position of
the flame are controlled by the flame holder 180, so that the flame
is placed inside the guide duct 110. The air flowed in along the
guide duct 110 is changed to a hot wind with a high temperature
while passing through the flame and then injected to the laundries
to be dried.
[0042] The mixing pipe 120 is formed with a mixing part 124 at one
side thereof to allow the air inside the cabinet to be flowed
therein. Since the mixing part 124 includes an opening which is
larger diameter than that of the nozzle 140, the gas injected from
the nozzle 140 and air flowed in are mixed with each other in the
mixing part 124. The mixing part 124 is formed in such a manner
that an end of the mixing part 120 is extended and has a hollow
cylindrical shape with an opening formed at the end thereof
corresponding to the nozzle 140.
[0043] The nozzle 140 is communicated with the gas pipe 130 and
detachably mounted on the valve 150. The nozzle 140 includes a gas
injection passage 142 along which the gas is injected, air intake
passages 144 communicated with the gas injection passage 142 to
allow the air to be flowed into the gas injection passage 142 and
fastening part 146 for mounting the nozzle 140 to the valve 150.
When the valve 150 is opened and the gas is supplied to the mixing
pipe 120 along the gas pipe 130, the gas is supplied to the mixing
pipe 120 through the gas injection passage 142. At this time, the
air is flowed in the gas injection passage 142 and the gas and the
air are thus mixed with each other.
[0044] A cross section a of the gas injection passage 142 is formed
smaller than a cross section b of the air intake passage 144. The
cross section a of the gas injection passage 142 refers to the
smallest of cross sections of the flow path of the gas injection
passage 142 and the cross section b of the air intake passage 144
refers to the smallest of cross sections of the flow path of the
air intake passage 144.
[0045] In the present embodiment, the cross sections of the gas
injection passage 142 and the air intake passage 144 are described
to have substantially a circular shape by way of an example. That
is to say, in the present embodiment, a diameter a of the gas
injection passage 142 is formed smaller than a diameter b of the
air intake passage 144. Also, a length c of the fastening part 146
is formed greater than the diameter b of the air intake passage
144. Herein, The diameter a of the gas injection passage 142 refers
to the smallest of diameters of the flow path of the gas injection
passage 142 and flow velocity of the gas is increased while passing
the section with such small diameter.
[0046] From the result of measuring shape, color and an amount of
carbon monoxide (CO) due incomplete combustion caused by the
nozzles 140 having various structures while controlling the
diameter a of the gas injection passage 142, the diameter b of the
air intake passage 144 and the length c of the fastening part 146,
it could be appreciated that the incomplete combustion is prevented
when the nozzle 140 has the shape as above described and the flame
produced by the combustion of the gas is close to a blue flame.
[0047] The nozzle 140 includes a nozzle 140a for a first gas and a
nozzle 140b for a second gas. In the present embodiment, the nozzle
140a for a first gas is a nozzle 140a for Liquefied Petroleum Gas
(LPG) and nozzle 140b for a second gas is a nozzle 140b for
Liquefied Natural Gas (LNG). Referring to FIG. 6, the diameter a of
the gas injection passage 142a of the LPG nozzle 140a is formed
smaller than the diameter a' of the gas injection passage 142b of
the LNG nozzle 140b and the diameter b of the air intake passage
144a of the LPG nozzle 140a is formed smaller than the diameter b'
of the air intake passage 144b of the LNG nozzle 140b. The reason
that the diameters of the LNG nozzle 140b is greater than the
diameters of the LPG nozzle 140a is because a more amount of the
LNG should be supplied compared to the LPG as a caloric value of
the LNG is smaller than a caloric value of the LPG.
[0048] Table 1 below shows the result of inspecting generation of a
red flame while supplying gas with the LPG nozzle 140a so that the
caloric value is 5,040 Kcal/h, and Table 2 shows the result of
measuring the generation of the red flame and noise (dB) while
varying the diameter b of the air intake passage 144a in a state
that the diameter a of the gas injection passage 142a is fixed to
1.4 mm and the length c of the fastening part 146a is fixed to 4.0
mm.
TABLE-US-00001 TABLE 1 Generation of red flame a b C 1.sup.st
2.sup.nd 3.sup.rd 1.0 1.8~2.2 3.8~4.2 .largecircle. .largecircle.
.largecircle. 1.2 1.8~2.2 3.8~4.2 X X X 1.4 1.8~2.2 3.8~4.2 X X X
1.6 1.8~2.2 3.8~4.2 X X X
TABLE-US-00002 TABLE 2 Generation of red flame a b c 1.sup.st
2.sup.nd 3.sup.rd Noise (dB) 1.4 1.0 4.0 .largecircle.
.largecircle. .largecircle. 35 1.5 .largecircle. .largecircle. X 35
2.0 X X X 37 2.5 X X X 40 3.0 X X X 43
[0049] As can be appreciated from Tables 1 and 2, in the case of
the NPG nozzle 140a, it is preferable that the diameter a of the
gas injection passage 142a is 1.2 to 1.6 mm, the diameter b of the
air intake passage 144a is 1.8 to 2.2 mm and the length c of the
fastening part 146a is 3.8 to 4.2 mm. When considering the noise,
the optimum flame is produced preferably when the diameter a of the
gas injection passage 142a is 1.4 mm, the diameter b of the air
intake passage 144a is 2.0 mm and the length c of the fastening
part 146a is 4 mm.
[0050] Table 3 below shows the result of inspecting generation of
the red flame while supplying gas with the LNG nozzle 140b so that
the caloric value is 5,040 Kcal/h, and Table 4 shows the result of
measuring the generation of the red flame and noise (dB) while
varying the diameter b' of the air intake passage 144b in a state
that the diameter a' of the gas injection passage 142b is fixed to
2.0 mm and the length c' of the fastening part 146b is fixed to 3.0
mm.
TABLE-US-00003 TABLE 3 Generation of red flame a{grave over ( )}
b{grave over ( )} c{grave over ( )} 1.sup.st 2.sup.nd 3.sup.rd 1.6
2.8~3.2 3.8~4.2 .largecircle. .largecircle. .largecircle. 1.8
2.8~3.2 3.8~4.2 X X X 2.0 2.8~3.2 3.8~4.2 X X X 2.2 2.8~3.2 3.8~4.2
X X X
TABLE-US-00004 TABLE 4 Generation of red flame a{grave over ( )}
b{grave over ( )} c{grave over ( )} 1.sup.st 2.sup.nd 3.sup.rd
Noise (dB) 2.0 2.0 4.0 .largecircle. .largecircle. .largecircle. 37
2.5 .largecircle. X X 38 3.0 X X X 40 3.5 X X X 45 4.0 X X X 50
[0051] As can be appreciated from Tables 3 and 4, in the case of
the LNG nozzle 140b, it is preferable that the diameter a' of the
gas injection passage 142b is 1.8 to 2.2 mm, the diameter b' of the
air intake passage 144b is 2.8 to 3.2 mm and the length c' of the
fastening part 146b is 3.8 to 4.2 mm. When considering the noise,
the optimum flame is produced preferably when the diameter a' of
the gas injection passage 142b is 2.0 mm, the diameter b' of the
air intake passage 144b is 3.0 mm and the length c' of the
fastening part 146b is 4 mm.
[0052] In a case of manufacturing the LPG nozzle 140a and the LNG
nozzle 140b so as to produce the optimum flame, the LPG nozzle 140a
supplies the gas of about 3.5 L/min and the LNG nozzle 14b supplies
the gas of about 8.0 L/min, thereby capable of generating the
caloric value of about 5,040 Kcal/h.
[0053] The nozzle 140 has a shape of a polygonal prism and each
face forming the polygon is formed with the air intake passage 144.
When the air intake passage 144 is formed on the face of the
polygon, processing of the air intake passage 144 can be
facilitated and a shape error generated upon the processing as
compared with a nozzle of which air intake passage is formed on
edge of the polygon. Particularly, it is preferable that the
sectional shape of the nozzle 140 is formed in a hexagon and the
air intake passage 144 is formed on each face forming the hexagon.
By forming the nozzle in the structure as described above, the
optimum flame can be produced. This structural characteristic is
also determined, as the structure capable of producing the optimum
flame, from the results of a plurality of experiments performed by
varying the sectional shape of the nozzle 140 and varying the
number of the air intake passage 144.
[0054] The flame holder 180 is installed in the mixing pipe 120 so
as to be disposed between the mixing pipe 120 and the guide duct
110. A mixture of the air and the gas forms a vortex by the flame
holder 180 and the mixture is thus burned in the vicinity of flame
holder 180. The flame holder 180 includes a body 182 formed with a
through hole part 182a through which the mixture supplied through
the mixing pipe 120 is injected, and a plurality of supports 184
which are extended from the body 182 to be connected with an end
portion of the mixing pipe 120. Herein, the body 182 is formed in a
ring shape, in which the through hole part 182a is formed in the
middle of the ring and a plurality of the wings 186 is formed at
the periphery of the ring. The wings 186 are provided in plural in
a radial direction on the periphery of the body 182, and a pair of
the supports 184 is extended from the wings which oppose to each
other. Herein, the wing 186 is bended towards the mixing pipe 120
with a predetermined angle.
[0055] The mixture injected to the outside of the mixing pipe 120
is ignited by the sparks generated by the ignition plug 170. Since
the mixture are spread by the body 182 and the wings 186 of the
flame holder 180, the flame produced is not formed long along the
guide duct 110 but is gathered in the vicinity of the flame holder
180. Since the flame is gathered in the middle of the inside of the
guide duct 110 by the aforementioned operation, it is possible to
prevent the mixing pipe 120 or the intake duct 70 is deformed or
damaged by the flame. Herein, the support 184 includes a mounting
part 184a fastened to the mixing pipe 120 and a fixing part 184b
which connects the mounting part 184a and the body 182, and a width
of the fixing part 184b is narrower than a width of the mounting
part 184a. Therefore, the contact area between the mixture and the
fixing part 184b is reduced and it is thus possible to prevent that
the mixture injected from the mixing pipe 120 is flowed back after
collided with the support 184. By the aforementioned operation, it
is possible to prevent the backflow of the flame in which the
mixture injected from the mixing pipe 120 is burned while being
flowed back to the mixing pipe 120 after collided with the support
184. Also, since the fixing part 184b of the support 184 has
smaller thickness than the mounting part 184a, it is possible to
effectively prevent the backflow of the flame.
[0056] The through hole part 182a has a large diameter d as
compared with a distance e between the wing 186 and the mixing pipe
120 (refer to FIGS. 7 and 8). Specifically, the diameter d of the
through hole part 182a is 9.8 to 10.2 and the distance e between
the wing 186 and the mixing pipe 120 is 8.8 to 9.2. When the
diameter d of the through hole part 182a and the distance e between
the wing 186 and the mixing pipe 120 were as aforementioned, the
flame had such a shape that the flame is clustered around the body
182 and a blue flame was also formed. This structure prevents that
the flame is formed long inside the guide duct 110 and the red
flame is produced, thereby capable of preventing the incomplete
combustion of the gas. The diameter d of the through hole part 182a
and the distance e between the wing 186 and the mixing pipe 120 as
described above are the values determined by experiments performed
plural times.
[0057] Hereinafter, operation of the dryer having a gas heater in
accordance with an embodiment of the present invention will be
described.
[0058] FIG. 8 is a plan view illustrating an intake flow path of
the dryer having a gas heater in accordance with an embodiment of
the present invention; FIG. 9 is a side sectional view illustrating
a circulation flow path of the dryer having a gas heater in
accordance with an embodiment of the present invention; and FIG. 10
is a plan view illustrating an exhaust flow path of the dryer
having a gas heater in accordance with an embodiment of the present
invention.
[0059] Referring to FIGS. 5 to 7 and FIGS. 8 to 10, when a user
manipulates an operation button (not shown), the power is applied
to the driving motor 90 to rotate the exhaust fan 82 and the drum
60. By the driving of the exhaust fan 82, the air flowed in the
inside of the cabinet 50 is moved to an upside of the cabinet 50
along the intake duct 70 vertically formed on a rear face of the
cabinet 50. At this time, as the valve 150 of the heater 100 is
opened and the gas is supplied along the gas pipe 130, the gas
passed through the valve 150 passes through the nozzle 140 to be
injected to the inside of the mixing pipe 120 and then primarily
mixed with the air flowed in through the nozzle 140 and secondarily
mixed with the air flowed in through the space between the mixing
pipe 120 and the nozzle 140. Herein, gas/air ratio of the mixture
is determined by the shape of the nozzle 140, or the structural
characteristics of the nozzle 140 such as the diameter a of the gas
injection passage 142, the diameter b of the air intake passage 144
and the length c of the fastening part 146, and the incomplete
combustion can be prevented when these structural parts has the
dimensions as described above. Of course, though the distance
between the nozzle 140 and the mixing pipe 120 is a factor that
determines the gas/air ratio of the mixture, in the present
invention, the distance between the nozzle 140 and the mixing pipe
120 is considered to be the same as that conventionally used and
thus not be described specifically.
[0060] When the mixture of the air and gas is injected through the
mixing pipe 120 and the flame is produced by the ignition plug 170.
Since the injected mixture collides with the flame to form a
vortex, the flame is laterally spread in the vicinity of the flame
holder 180. At this time, since the fixing part 184b of the support
184 has thinner thickness than the thickness of the mounting part
184a, the support 184 of the flame holder 180 can prevent the
mixture moving toward the support 184 is collided with the support
184 and the body 182 and then flowed back. Since the flame is
spread in the vicinity of the body 182 of the flame holder 180 and
is prevented from being flowed back to the mixing pipe 120 along
the support 184, it is possible to prevent the incomplete
combustion. Also, since this flame is gathered in a middle of the
guide duct 110 by the flame holder 180, it is possible to prevent
the deformation or damage of the mixing pipe 120 and the intake
duct 70. This is because it is possible to prevent that the flame
is formed long inside the guide duct 110 as the mixture is spread
by the body 182 and the wing 186 of the flame holder 180 and it is
thus possible that the flame is produced at a position close to the
intake duct 70.
[0061] The air flowed in the inside of the intake duct 70 along the
guide duct 110 is heated to dry air with a high temperature while
being brought into contact with the flame. After that, the air
flowed in the inside of the drum 60 through the through hole part
62a is swirled and brought into contact with the laundries to be
dried to perform the dry operation.
[0062] The front panel 64 placed between an inner wall of the
cabinet 50 and the opening of the drum 60 is formed with an exhaust
hole 64a. The air is exhausted to the outside of the drum 60
through the exhaust hole 64a, flowed to the housing 86 of the
exhaust fan 82 through the connection duct 84 communicated with the
exhaust hole 64a, then move from the housing 86 along the exhaust
duct 80 and finally exhausted to the outside of the cabinet 50
through the discharge port 54.
[0063] FIG. 11 is a graph showing content of carbon monoxide in
exhaust gas of the dryer having a nozzle and a flame holder for LPG
and FIG. 12 is a graph showing content of carbon monoxide in
exhaust gas of the dryer having a nozzle and a flame holder for
LNG.
[0064] Referring to FIGS. 5 to 7, 11 and 12, the dimensions of the
nozzle 140 and the flame holder 180 as described above are
determined as the optimum dimensions in an experiment, in which
shape and color of the flame and carbon content in the exhaust gas
according to structural variation of the nozzle 140 and the flame
holder 180, performed on August, 2007 by New Energy Laboratory in
department of mechanical engineering of Incheon University
according to a request of present assignee.
[0065] In addition, the nozzle 140 and the flame holder 180
manufactured with the above described dimensions were installed in
the dryer to be subject to a safety inspection. Particularly, with
respect to the content of carbon monoxide in the exhaust gas, the
content of the carbon monoxide was detected by less than 6 ppm in a
dryer with the LPG nozzle 140a and by less than 7 ppm in a dryer
with the LNG nozzle 140b. Therefore, it can be appreciated that the
incomplete combustion is prevented.
[0066] Although the present invention has been described with
reference to the embodiments shown in the drawings, it should be
understood that these embodiments are provided for illustrative
purpose and that various equivalent modifications and alterations
will be apparent to those skilled in the art without departing from
the scope and spirit of this invention. In addition, although the
present invention has been described with reference to the dryer as
specifically described herein, it should be noted that the dryer
has been illustrated by way of example, and that the gas heater of
the present invention may be applied to other product such as a
washing machine, without being limited to the dryer in its
application. Therefore, the scope and spirit of the invention is
limited only by the claims set forth herein as follows.
* * * * *