U.S. patent application number 12/108013 was filed with the patent office on 2008-10-30 for burner.
This patent application is currently assigned to Paloma Industries, Limited. Invention is credited to Hideo Chikazawa, Hiroshi Oda.
Application Number | 20080268394 12/108013 |
Document ID | / |
Family ID | 39522204 |
Filed Date | 2008-10-30 |
United States Patent
Application |
20080268394 |
Kind Code |
A1 |
Oda; Hiroshi ; et
al. |
October 30, 2008 |
BURNER
Abstract
A burner including a burner main body having a mixing pipe to
which a fuel gas and combustion air are supplied and a mixing
chamber provided at a top end on the downstream side of the mixing
pipe, and a burner head, which is provided at an upper part of the
burner main body. The burner head communicates with the mixing
chamber and ejects the mixed gas of the fuel gas and air mixed in
the mixing chamber. The burner head has a cylindrical shape and is
provided right above the mixing chamber of the burner main body.
The burner head has several first and second burner ports bored
around almost an entire periphery of a side face thereof. The
mixing pipe extends in a direction where the mixing pipe is crossed
with an axis line of the burner head at substantially right angles
to each other.
Inventors: |
Oda; Hiroshi; (Nagoya-shi,
JP) ; Chikazawa; Hideo; (Nagoya-shi, JP) |
Correspondence
Address: |
BURR & BROWN
PO BOX 7068
SYRACUSE
NY
13261-7068
US
|
Assignee: |
Paloma Industries, Limited
Nagoya-shi
JP
|
Family ID: |
39522204 |
Appl. No.: |
12/108013 |
Filed: |
April 23, 2008 |
Current U.S.
Class: |
431/354 |
Current CPC
Class: |
F23D 14/583 20130101;
F23D 14/065 20130101 |
Class at
Publication: |
431/354 |
International
Class: |
F23D 14/62 20060101
F23D014/62; F23D 14/04 20060101 F23D014/04 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 27, 2007 |
JP |
2007-119829 |
Claims
1. A burner comprising: a burner main body having a mixing pipe to
be supplied with a fuel gas and combustion air, and formed with a
mixing chamber at a top end on a downstream side of the mixing
pipe; and a burner head provided at an upper part of the burner
main body while communicating with the mixing chamber, and having
burner ports for ejecting the mixed gas of the fuel gas and
combustion air mixed in the mixing chamber, wherein the burner head
is in a cylindrical shape having a plurality of burner ports bored
around an almost whole periphery of a side face thereof, and
provided right above a mixing chamber of a burner main body; and
wherein the mixing pipe is provided to be directed in a direction
where the mixing pipe is crossed with an axis line of the burner
head at substantially right angles to each other.
2. The burner according to claim 1, wherein the burner ports
comprise a slit-shaped first burner port in the vertical direction
and a line of plural circular second burner ports arranged in
vertical direction, the slit-shaped first burner port and the line
of plural round second burner ports each being alternately arranged
in the peripheral direction and the vertical directions.
Description
BACKGROUND OF THE INVENTION
[0001] This application claims the entire benefit of Japanese
Patent Application Number 2007-119829 filed on Apr. 27, 2007, the
entirety of which is incorporated by reference.
[0002] 1. Field of the Invention
[0003] The present invention relates to a burner used for a gas
combustion appliance such as a hot water storage type water
heater.
[0004] 2. Description of the Background Art
[0005] A conventional burner includes a burner main body having a
mixing pipe to which fuel gas and combustion air are supplied, and
a mixing chamber at a top end on a downstream side of the mixing
pipe. Further, the burner includes a burner head at an upper part
of the burner main body while communicating with the mixing chamber
and including a burner port for ejecting a mixed gas of the fuel
gas and combustion air from the mixing chamber. For example, patent
document 1 describes that such a burner is used to heat hot and
cold water and the like in a gas combustion appliance such as a hot
water storage type water heater. The burner used in this patent
document 1 is a Bunsen burner in a combustion chamber arranged
below a hot water storage chamber, and includes a burner main body
facing a top end of a gas nozzle and having a throat part taking
combustion air in, and a burner head placed on the burner main body
and having intermittently burner ports therearound.
[0006] Patent document 1: Japanese Unexamined Patent Publication
No. 2001-304691
SUMMARY OF THE INVENTION
[0007] From a viewpoint to suppress generating NOx (nitrogen oxide)
in a combustion gas, it is desirable that a burner is an
all-primary air burner taking in air which has more than the
theoretical equivalence required for combustion as primary air. In
the all-primary air burner, the highest temperature of a flame can
be decreased by all primary low-load combustion, and thus NOx
generation can be suppressed.
[0008] However, when an inner pressure of the burner is high, a
volume of primary air taken in becomes insufficient. Particularly,
when a burner port area is small like the burner disclosed in the
above-described patent document 1, an ejection speed of the mixing
air of primary air and air for combustion from the burner port
becomes high to increase fluid resistance. Since sufficient primary
air cannot be taken in due to increased inner pressure it becomes
necessary to compulsively supply combustion air using a fan. Thus,
downsizing of a burner cannot be made, which increases the
cost.
[0009] An object of the present invention is to provide a burner
capable of taking in sufficient primary air and mixing it with fuel
gas without using a fan, and being used as an all primary air
burner.
[0010] In order to achieve the above-described object, a first
aspect of the invention includes a burner head, wherein the burner
head is in a cylindrical shape having a plurality of burner ports
bored around an almost whole periphery of a side face of the burner
head, and is provided right above a mixing chamber of a burner main
body while a mixing pipe is directed in a direction where an axis
line of the mixing pipe crosses with an axis line of the burner
head at substantially right angles.
[0011] A second aspect of the invention includes, in addition to
the first aspect, the burner ports including a vertical slit-shaped
first burner port, and the line of plural round second burner ports
arranged vertically, each of which is alternately arranged in the
peripheral direction and the vertical directions, in order to
obtain suitable burner ports capable of having a necessary burner
port area and securing rigidity.
[0012] According to the first aspect of the invention, a sufficient
burner port area can be provided with the cylindrical burner head,
and the ejection speed of mixing gas from the burner ports
decreases to suppress fluid resistance. In addition, the mixing air
can be smoothly and uniformly supplied from the mixing chamber to
the burner head, and thus the whole height can be suppressed to be
small. Thus, the burner can be suitably used as an all-primary air
burner and a natural combustion type burner not using a fan, and
thus downsizing of the burner and reduction of cost can be
expected. Further, since a combustion surface becomes a side
surface, dropping materials from above are not accumulated on the
burner ports.
[0013] According to the second aspect of the invention, in addition
to the effect of the first aspect, while a necessary burner port
area is provided by the first burner ports, rigidity can be secured
by the second burner ports.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 are descriptive views of a burner, and FIG. 1A
illustrates a plane view, FIG. 1B illustrates a front view, and
FIG. 1C illustrates a right side face;
[0015] FIG. 2 is an enlarged cross sectional view taken along an
A-A line;
[0016] FIG. 3A is a cross sectional view taken along a B-B line,
and FIG. 3B is a cross sectional view taken along a C-C line;
[0017] FIG. 4A is a descriptive view of a caulking part between an
upper plate and a side plate, and FIG. 4B is a descriptive view of
a caulking part between a lower plate and a side plate;
[0018] FIG. 5 is a descriptive view to illustrate a lower portion
of a hot water storage type water heater; and
[0019] FIG. 6A is a descriptive view of a modified example of a
caulking part between the upper plate and the side plate, and FIG.
6B is a descriptive view of a modified example of a caulking part
between the lower plate and the side plate.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0020] Embodiments of the present invention will be described below
with reference to the drawings.
[0021] FIG. 1 are descriptive views of a burner, and FIG. 1A
illustrates a plane view, FIG. 1B illustrates a front view, and
FIG. 1C illustrates a right side face, respectively. A burner 1
includes a burner main body 2 on a lower side thereof, and a burner
head 3 placed on the burner main body 2. The burner main body 2
includes a cylindrical mixing pipe 4 at an end part thereof, having
a throat part 5 to which fuel gas and combustion air are supplied,
and a round shaped mixing chamber 6 continuously provided at a
downstream end of the mixing pipe 4. The burner main body 2 is
formed with a pair of upper and lower metal plates which are bonded
by caulking at a center thereof along the whole periphery. The
mixing chamber 6 has a space having a radius larger than that of
the mixing pipe 4, and is continuously provided to the mixing pipe
4 in such a way that an axis line of the mixing pipe 4 in the
horizontal direction is orthogonally crossed with an axis line of
the mixing chamber 6 in a vertical direction.
[0022] Further, an internal pipe 7 is provided in the mixing pipe
4. As illustrated in FIGS. 2 and 3, the internal pipe 7 is a pipe
in which one end thereof is inserted in and held by the mixing pipe
4, and is formed with a pair of upper and lower metal plates which
are bonded by caulking at the center of left and right side edges
similar to the burner main body 2. The other end of the internal
pipe 7 is protruded in the mixing chamber 6 in its diameter
direction so as to be an extension pipe 8 to extend the mixing pipe
4. A protruded end of the extension pipe 8 is cut to be inclined so
as to have an upward opening 9. A chamfered part 10 is provided at
the bottom surface of the extension pipe 8 below the opening 9 for
stabilizing the extension pipe 8 and comes into contact with the
bottom surface of the mixing chamber 6.
[0023] On the other hand, the burner head 3 has cylindrical shape
comprises an upper plate 11, a lower plate 12, and a side plate 13.
The upper plate 11 and lower plate 12 have round shapes when viewed
from a plane side, and the side plate 13 surrounds along peripheral
edges of both the plates 11 and 12. As illustrated in FIGS. 4A and
4B, the burner head 3 is formed by folding back of the ends of
upper and lower plates 11 and 12 clipping the upper and lower ends
of the side plate 12 between them at peripheral edges of the upper
plate 11 and the lower plate 12 and by being caulking bonded. The
upper and lower ends of the side plate 13 are bent to be outwardly
enlarged. Further, ring-shaped ribs 14 and 14 having different
diameters are concentrically formed on the upper plate 11 for
absorbing deformation due to thermal stress.
[0024] Furthermore, as illustrated in FIG. 1D where the D part is
enlarged in FIG. 1A a long slit-shaped first burner port 15 and a
line of four circular second burner ports 16, 16, . . . are
provided on the side plate 13. The first burner port 15 is long in
a vertical direction and the second burner ports 16, 16, . . . are
lined up in the vertical upper and lower direction. The first
burner port 15 and the line of the second burner ports 16, 16, and
. . . are alternately arranged each other in a peripheral direction
and the upper and lower direction along an almost whole periphery
(only a part thereof is illustrated in FIG. 1D). The reasons of
together using the slit shape and round shape burner ports are to
have a burner port area by the slit-shaped first burner ports 15
and secure rigidity by the round second burner ports 16. Further,
at the lower plate 12, a round communication hole 17 is provided.
The communication hole 17 has an opening area almost equal to a
total opening area of the first burner ports 15 and the second
burner ports 16. A peripheral edge of the communication hole 17 is
caulking bonded with an upper part of the mixing chamber 6 in the
burner main body 2 to thereby co-axially position the burner head 3
right above the mixing chamber 6.
[0025] For example, the burner 1 having the above-described
constitution is used for a hot water storage type water heater 20
as illustrated in FIG. 5. This hot water storage type water heater
20 includes a hot water storage chamber 23 upper and lower sides of
which are closed with an upper mirror plate (which are not
illustrated) and a lower mirror plate 22, on the upper side of a
cylindrical main body 21. The hot water storage type water heater
20 includes a combustion chamber 24 below the hot water storage
chamber 23. The burner 1 is provided in the combustion chamber 24.
In addition, a water supplying pipe to supply water into the hot
water storage chamber 23 and a hot water supplying pipe to
externally take out hot water from the hot water storage chamber 23
(both pipes are not illustrated) are provided on the upper side of
the hot water storage chamber 23.
[0026] An exhaust pipe 25 is provided on the center of axle of hot
water storage chamber 23, and this exhaust pipe 25 penetrates the
hot water storage chamber 23 to be protruded toward the upper side
of the main body 21. Through the exhaust pipe 25, combustion gas
generated in the combustion chamber 24 is exhausted outside the
main body 21. A baffle plate (not illustrated) having a spiral
passage is provided inside the exhaust pipe 25.
[0027] The burner 1 is supported on a disc-shaped placing base 26
provided at a lower side of the combustion chamber 24 by a
supporting plate 27. The throat part 5 of the burner main body 2
faces a gas nozzle 28 whose top end protrudes into the combustion
chamber 24. The burner head 3 is positioned at a center of the
combustion chamber 24. The reference numeral "29" indicates a pilot
burner.
[0028] The burner 1 is supported by the supporting plate 27 so that
the burner head 3 is protruded into a space covered by a lower
mirror plate 22 and the side surface of the burner 1 faces the
whole periphery of the hot water storage chamber 23.
[0029] Plural air feed ports 30, 30, and . . . for air for
combustion are arranged at predetermined intervals in the
peripheral direction at the lower peripheral edge of the placing
base 26. By means of the air feed ports, an inside of the placing
base 26 is communicated with an external of the main body 21.
Inside the placing base 26, a partition plate 31 which separates
inside of the placing base 26 into upper and lower parts is
provided. The partition has an opening at a center thereof. On the
other hand, an air passage 32 is provided vertically on a gas
nozzle 28 side of the combustion chamber 24, where the air passage
32 partitions the inside space of the chamber combustion 24.
However, an upper space in the placing base 26 partitioned by the
partition plate 31 is kept communicated with the throat part 5 of
the burner main body 2. Thus, as indicated by an arrow, external
air passes through the opening of the partition plate 31 and
reaches to the air passage 32 after flowing into the placing base
26 from the air feed port 30. Then, the air goes up through the air
passage 32 and is introduced into the burner main body 2.
[0030] In the hot water storage type water heater 20, when an
ignition knob of a controller (not illustrated) provided at an
external of the main body 21 is operated, a gas flow passage to the
pilot burner 29 is opened and the pilot burner 29 is ignited. When
the ignition is detected by a thermocouple (not illustrated), an
electromagnetic valve of the gas flow path is opened and is kept
open. In such a condition, when the ignition knob is operated to
open a main gas flow passage, the fuel gas ejects from the gas
nozzle 28 to be supplied from the throat part 5 to the burner main
body 2. By the ejecting energy of the fuel gas, air outside of the
main body 21 is taken into the mixing pipe 4 of the burner main
body 2 from the air feed port 30 through the inside of the placing
base 26 and the air passage 32.
[0031] At this time, since the length from the throat part 5 to the
opening 9 is sufficiently kept by the extension pipe 8 protruding
inside the mixing chamber 6, the fuel gas and the air for
combustion are suitably mixed. In addition to this, the mixed gas
ejecting from the opening 9 collides with an inner surface of the
mixing chamber 6, and is divided into two directions. Then the
mixed gas reversely directs along the inner surface of the mixing
chamber 6. Thus, the flow of the gas promotes mixing of the fuel
gas and the combustion air more. Further, an eddy flow does not
occur at the both sides of the extension pipe 8.
[0032] When the mixing chamber 6 is filled with the mixed gas, the
mixed gas is led into the burner head 3 through the communication
hole 17, and ejects from respective first and second burner ports
15 and 16 for combustion. At this time, since ejecting speeds of
the mixed gases from the burner ports 15 and 16 are small, the
flame comes close to the burner ports 15 and 16. Thus, surface
combustion is carried out at an almost whole surface of the side
plate 13, and temperatures of the burner ports become 800.degree.
C. or more. Further, since the whole surface of the cylindrical
side face becomes a combusted surface, the influence of thermal
stress can be suppressed.
[0033] The high temperature combustion gas generated by burner
combustion goes up along a lower surface of the lower mirror plate
22, and passes through the central exhaust pipe 25 to be exhausted
to outside of the main body 21. By the movement of the combustion
gas, hot water in the hot water storage chamber 23 is heated by the
lower mirror plate 22 and the exhaust pipe 25.
[0034] On the other hand, radiation heat generated by combustion at
the side surface of the burner head 3 is radially radiated from the
burner head 3 as illustrated with wavy arrows. However, since the
whole side surface of the burner head 3 faces the hot water storage
chamber 23, the radiation heat is effectively transmitted to hot
water in the hot water storage chamber 23 to heat the hot
water.
[0035] Since the radiation heat is effectively transmitted to the
hot water storage chamber 23 as illustrated above, a temperature of
the air below the burner 1 in the combustion chamber 24 does not
become high. Thus, the combustion air from the air feed port 30 to
the throat part 5 can be suppressed to become high temperature.
Therefore, a volume of the combustion air is not expanded, and a
sufficient amount of primary air can be taken into the burner 1,
which leads to the reduction of NOx generation.
[0036] According to the burner 1 of the above-described embodiment,
the burner head 3 is in a cylindrical shape having a plurality of
first and second burner ports 15 and 16 bored at an almost whole
periphery of the side face thereof, and is provided right above the
mixing chamber 6 of the burner main body 2. On the other hand,
since the mixing pipe 4 is provided to direct to a direction where
the mixing pipe 4 is crossed with the axis line of the burner head
3 at substantially right angles to each other, the sufficient
burner port area can be secured, and the ejection speed of the
mixing gas from the first and second burner ports 15 and 16 is
decreased to suppress fluid resistance. In addition, the mixing air
can be smoothly and uniformly supplied from the mixing chamber 6 to
the burner head 3, and thus the size of the whole burner height can
be suppressed to be small. Thus, the burner can be suitably used as
an all primary air burner and a natural combustion type burner not
using a fan, and downsizing and reduction of cost can be expected.
Further, since a combustion surface becomes the side surface,
dropping materials from an upper side are not accumulated on the
first and second burner ports 15 and 16.
[0037] Particularly, since the burner port is configured that a
slit-shaped first burner port 15 in the vertical direction, and the
line of plural round second burner ports 16 arranged in the
vertical directions are alternately arranged each other in the
peripheral direction and the vertical directions, a preferable
burner port can be arranged, in which while a necessary burner port
area is provided by the first burner port 15, rigidity can be kept
by the second burner ports 16.
[0038] Further, as the extension pipe 8 protruding inside the
mixing chamber 6 is provided on the mixing pipe 4 of the burner
main body 2, a sufficient mixing distance inside the mixing chamber
can be secured. Further, since an eddy flow does not occur when the
mixing air flows into the mixing chamber 6 from the mixing pipe 4,
the required primary air can be taken in using ejecting energy of
the fuel gas. Further, the fuel gas and the air for combustion can
be favorably mixed in the mixing chamber 6. Furthermore, since the
protruded end of the extension pipe 8 is cut to be inclined so as
to have the upward opening 9, a preferable configuration in which
the more amount of primary air is taken can be obtained.
[0039] It should be noted that in the burner head, a burner port in
a burner head is not limited to the burner port in the
above-described embodiment. A size, a shape, an arrangement
pattern, and the like can be suitably changed. The structure of an
upper plate and a lower plate, and connecting configuration are not
limited to the above-described embodiment. For example, when
caulking parts between an upper or lower plate and a side plate are
bent in a V shape toward an opposite side of the upper or lower
plate as illustrated in FIG. 6, the strength is increased, and thus
warping under thermal conditions can be effectively prevented.
[0040] Additionally, in the above-described embodiment, the
protruded end of the extension pipe is cut to be inclined so as to
have the upward opening. However, contrary to this, the protruded
end may be cut to be inclined so as to have a downward opening, or
be cut in the vertical direction so as to have a sideways opening.
In these cases, the amount of primary air taken in is more
increased compared to a burner main body not having an extension
pipe.
[0041] Further, an extension pipe is not limited to the pipe using
an end part of an internal pipe. An extension pipe can be formed by
connecting only a portion corresponding to an opening edge of a
mixing pipe in a mixing chamber.
[0042] Furthermore, a burner of the present invention is not
limited to the above-described hot water storage type water heater,
and can be used as heating means in the other gas combustion
appliance such as a hot water supply appliance in which water
passing through the inside of the appliance is heated by a heat
exchanger.
* * * * *