U.S. patent application number 12/876573 was filed with the patent office on 2011-03-10 for hot air heater.
Invention is credited to Keiichi Ito, Shigeru Suzuki, Hideki Watanabe.
Application Number | 20110057047 12/876573 |
Document ID | / |
Family ID | 43646947 |
Filed Date | 2011-03-10 |
United States Patent
Application |
20110057047 |
Kind Code |
A1 |
Watanabe; Hideki ; et
al. |
March 10, 2011 |
HOT AIR HEATER
Abstract
A hot air heater has a housing having formed therein an inlet
port for sucking room air and an outlet port. A circulation fan, a
burner, and a heat exchanger which causes to flow combustion gas
from the burner through an inside of the heat exchanger are housed
in the housing. The room air sucked by operation of the circulation
fan into the inlet port is heated by the heat exchanger for blowing
forward as hot air out of the outlet port. A supporting plate is
disposed to support the heat exchanger inside the housing. In order
to limit the temperature increase in the housing by heat
transmission through the supporting plate, and in order to improve
the thermal efficiency, the supporting plate is provided with
radiating fins. Preferably, the radiating fins are made up of
cut-and-raised pieces formed in the supporting plate.
Inventors: |
Watanabe; Hideki; (Aichi,
JP) ; Suzuki; Shigeru; (Aichi, JP) ; Ito;
Keiichi; (Aichi, JP) |
Family ID: |
43646947 |
Appl. No.: |
12/876573 |
Filed: |
September 7, 2010 |
Current U.S.
Class: |
237/55 ;
165/185 |
Current CPC
Class: |
F28F 1/24 20130101; F28F
1/12 20130101; F28F 2215/08 20130101; F24H 3/087 20130101; F24D
19/0082 20130101; F28F 9/0131 20130101 |
Class at
Publication: |
237/55 ;
165/185 |
International
Class: |
F24B 7/00 20060101
F24B007/00; F28F 7/00 20060101 F28F007/00 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 8, 2009 |
JP |
2009-206672 |
Claims
1. A hot air heater comprising: a housing having formed therein an
inlet port for sucking room air and an outlet port; and a
circulation fan, a burner, and a heat exchanger, all being housed
in the housing, the heat exchanger being arranged to cause
combustion gas from the burner to flow through an inside of the
heat exchanger so that the room air sucked by operating the
circulation fan into the inlet port is heated by the heat exchanger
for blowing forward as hot air out of the outlet port, wherein a
supporting plate is disposed to support the heat exchanger inside
the housing and wherein the supporting plate is provided with a
radiating fin.
2. The hot air heater according to claim 1, wherein the radiating
fin is disposed such that a plate surface of the fin obliquely
crosses the direction of flow of the air from the circulation
fan.
3. The hot air heater according to claim 1, wherein the radiating
fin is made up of a cut-and-raised piece formed in the supporting
plate.
4. The hot air heater according to claim 2, wherein the radiating
fin is made up of a cut-and-raised piece formed in the supporting
plate.
Description
[0001] This application claims priority under 35 U.S.C. .sctn.119
to Japanese Patent Application No. 2009-206672, filed Sep. 8, 2009,
which is incorporated by reference.
BACKGROUND
[0002] 1. Technical Field
[0003] The present invention relates to a hot air heater (or forced
flue heater) that heats the room air by combustion gas from a
burner through a heat exchanger.
[0004] 2. Related Art
[0005] As this kind of hot air heater, there is known one having
the following construction. Within a housing having formed therein
an inlet port for sucking room air and an outlet port, there are
housed a circulation fan, a burner, and a heat exchanger which is
arranged to cause to flow combustion gas (or flue gas) from the
burner through an inside of the heat exchanger. The air sucked from
the inlet port by the operation of the circulation fan is heated by
the heat exchanger and is blown out of the outlet port as hot air
(see, e.g., Patent Document 1).
[0006] Although not disclosed in Patent Document 1, this kind of
hot air heater is provided with a supporting plate for supporting
the heat exchanger inside the housing. The supporting plate is
ordinarily constituted by a simple plate member and is generally
fixed to the inside of the housing by means of screws.
[0007] It is, however, to be noted that the heat exchanger, when a
fuel is burned in the burner, will reach a relatively high
temperature. The heat from the heat exchanger will be transmitted
through the supporting plate to that part of the housing to which
the supporting plate is fixed by screwing, with the result that
such a part will reach a high temperature.
[0008] Patent Document 1: JP-A-2003-121004
SUMMARY
[0009] In view of the above problems, it is an advantage of the
invention to provide a hot air heater in which the temperature
increase in the housing by heat transmission through the supporting
plate can be limited and in which the thermal efficiency can be
improved.
[0010] In order to solve the above-mentioned problems, this
invention is a hot air heater comprising: a housing having formed
therein an inlet port for sucking room air and an outlet port; a
circulation fan, a burner, and a heat exchanger, all being housed
in the housing. The heat exchanger is arranged to cause combustion
gas from the burner to flow through an inside of the heat exchanger
so that the room air sucked by operating the circulation fan into
the inlet port is heated by the heat exchanger for blowing forward
as hot air out of the outlet port. In the above-mentioned hot air
heater, a supporting plate is disposed to support the heat
exchanger inside the housing, and the supporting plate is provided
with a radiating fin.
[0011] According to the invention, the heat that is transmitted
from the heat exchanger to the supporting plate is radiated from
the radiating fin. The amount of heat to be transmitted to the
housing through the supporting plate is reduced and, consequently,
the temperature increase in the housing can be limited. At the same
time, since the air flowing around the supporting plate gets heated
by the heat radiation from the radiating fin, the thermal
efficiency is improved.
[0012] Preferably, the radiating fin is disposed such that a plate
surface of the fin obliquely crosses the direction of flow of the
air from the circulation fan. According to this arrangement, the
heat exchange between the radiating fin and the flow of the air is
performed efficiently. As a result, the reduction in the amount of
heat transfer to the housing and also the heating of the air can be
accelerated.
[0013] In this invention, preferably, the radiating fin is made up
of a cut-and-raised piece formed in the supporting plate. According
to this arrangement, unlike a case in which a radiating fin in the
form of a member separate from the supporting plate is fixed to the
supporting plate, the cost can be reduced by minimizing the number
of constituent parts. Further, the opening that is formed by the
cut-and-raised piece of the radiating fin contributes to the
reduction in the heat transfer area of the supporting plate.
Consequently, the amount of heat transfer to the housing can
further reduced.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The invention will now be described with reference to the
accompanying drawings in which:
[0015] FIG. 1 is a perspective view of a hot air heater according
to an embodiment of this invention;
[0016] FIG. 2 is a sectional side view of the hot air heater
according to the embodiment of this invention;
[0017] FIG. 3 is a sectional front view taken along the line
III-III in FIG. 2;
[0018] FIG. 4 is an enlarged plan view, partly shown in section, of
a main part taken along the line IV-IV in FIG. 3; and
[0019] FIG. 5 is a perspective view of a main part of the hot air
heater according to an embodiment of this invention.
DESCRIPTION OF EXEMPLARY EMBODIMENTS
[0020] With reference to FIGS. 1 through 3, reference numeral 1
denotes a housing of a hot air heater according to an embodiment of
this invention. The housing 1 is made up of: a main body
constituted by a rear plate part 11, a right-side side-plate part
12 and a left-side side-plate part 12, a top plate part 13, and a
bottom plate part 14; and a front panel 15 which covers the front
surface of the main body. There are formed, on an upper portion of
the rear plate part 11, an inlet port la for sucking the room air
and, on a lower part of the front panel 15, an outlet port lb.
[0021] On the top plate part 13 of the housing 1 there is provided
an operation panel 16. Further, on an outer surface of the rear
plate part 11 of the housing 1, there is disposed a guard frame 17
which encloses the piping space among a supply and exhaust duct
(not illustrated) which extends outdoors, an exhaust pipe 53, and a
combustion fan 6.
[0022] At an upper inside portion of the housing 1 there is housed
a circulation fan 2. The circulation fan 2 is disposed inside a fan
casing 21 which faces the inlet port 1a, and is constituted by an
oblong cross flow fan driven by a motor 22.
[0023] Inside the housing 1 there is defined an air passage 3 which
connects the fan casing 21 and the outlet port 1b together. The air
passage 3 is enclosed by: the rear plate part 11; a first lateral
partition plate 31 which is disposed on the inside of the left-side
side-plate part 12 (left as seen in FIG. 3); a second lateral
partition plate 32 which extends downward from the right end part,
as seen in FIG. 3, of the fan casing 21; a lower partition plate 33
which is disposed slightly below the lower end of the outlet port
1b; and a front partition plate 34 which extends downward from the
front edge of the fan casing 21.
[0024] Inside the housing 1 there is further housed a cylindrical
burner 4 which is supplied with a fuel gas through a gas valve unit
41 and a pipe 42 connected thereto, the burner 4 being housed in a
manner to pass through a lower part of the second lateral partition
plate 32. There is also housed a heat exchanger 5 which is
positioned inside the air passage 3 and which causes the combustion
gas (flue gas) of the burner 4 to flow through the inside. It is
thus so arranged that the room air sucked from the inlet port 1a by
operating the circulation fan 2 is heated by the heat exchanger 5
and is blown out of the outlet port 1b into the room as hot
air.
[0025] Inside the housing 1 there is also housed a combustion fan 6
which supplies the burner 4 with outside air as combustion air
through an air supply duct section of the supply and exhaust duct.
The combustion fan 6 is constituted by a centrifugal fan which is
driven by a motor 62 and which is disposed inside a fan casing 61
that is fixed to the rear plate part 11 of the housing 1. In
addition, a humidification water reservoir 7 to be filled with
water is disposed below the lower partition plate 33. It is thus so
arranged that the hot air is supplied with steam through an opening
33a formed through the lower partition plate 33. That lower end
part 15a of the front panel 15 which lies below the outlet port 1b
is arranged to be detachable so that the humidification water
reservoir 7 can be taken out of position for refilling it with
water.
[0026] The heat exchanger 5 is provided with: a combustion tube 51
which extends leftward as seen in FIG. 3 from the burner 4; a
bellows-type of heat exchange tube 52 which is laterally disposed
above the combustion tube 51; and an exhaust pipe 53 which is
laterally disposed between the combustion tube 51 and the heat
exchange tube 52. The left end of the combustion tube 51, which
corresponds to the downstream end thereof, and the left end of the
heat exchange tube 52, which corresponds to an upstream end
thereof, are brought into fluid flow communication with each other
through a box 54. Also, the right end of the heat exchange tube 52,
which corresponds to the downstream end thereof, and the right end
of the exhaust pipe 53, which corresponds to the upstream end
thereof, are brought into fluid flow communication with each other
through a box 55. It is thus so arranged that the combustion gas
(flue gas) flows through the combustion tube 51, the box 54, the
heat exchange tube 52, and the box 55 into the exhaust pipe 53. The
downstream end of the exhaust pipe 53 is projected out of the rear
surface of the housing 1 through the rear plate part 11 and is
connected to an exhaust duct part of the supply and exhaust
duct.
[0027] The heat exchanger 5 is supported by a supporting plate 8
inside the housing 1. As shown in FIGS. 4 and 5, this supporting
plate 8 has: a front plate part 81 which is fixed with screws 81a
to a fixing part 31a formed by cutting and raising the first
lateral partition plate 31; and a side plate part 82 which is bent
rearward from laterally inner edge part of the front plate part 81
and which is fixed with screws 82a to the outside surface of the
box 54 of the heat exchanger 5. On a laterally outward edge part of
the front plate part 81, there is formed, by bending, a flange part
83 which is intended to close the openings that were formed as a
result of cutting and raising of the fixing part 31a of the first
lateral partition plate 31. On a rear edge part of the side plate
part 82, there is formed, by bending, a flange part 84 which comes
into abutment with the rear plate part 11 of the housing 1. The
flange part 84 is engaged with a hook part 11a provided in the rear
plate part 11 at an engaging hole 84a that is formed in the flange
part 84.
[0028] With the above-mentioned arrangement as it is, the heat from
the heat exchanger 5 will be transmitted through the supporting
plate 8 to the first lateral partition plate 31 or to the rear
plate part 11, with the result that the housing 1 rises in
temperature.
[0029] As a solution, in this embodiment, there are disposed a
plurality of radiating fins 85 in the front plate part 81 and in
the side plate part 82, respectively, of the supporting plate 8.
According to this arrangement, the heat transmitted from the heat
exchanger 5 to the supporting plate 8 is radiated from the
radiating fins 85. The amount of heat to be transmitted to the
housing 1 through the supporting plate 8 is reduced and,
consequently, the temperature rise in the housing 1 can be limited.
At the same time, the air that flows around the supporting plate 8
is heated by radiation from the radiating fins 85. In other words,
the supporting plate 8 functions efficiently as a heat exchange
member, and the thermal efficiency also improves.
[0030] Each of the radiating fins 85 is disposed in a manner such
that the plate surface thereof obliquely crosses the direction of
flow of the air from the circulation fan 2 (i.e., crosses the
vertical direction at an inclination). Therefore, the heat exchange
takes place efficiently between the radiating fins 85 and the air
flow, with the result that the reduction in the amount of heat
transfer to the housing 1 and also the heating of the air can be
accelerated.
[0031] Alternatively, it may be considered to form the radiating
fins 85 in a plate member that is separate from the supporting
plate 8 and then to fix the radiating fins 85 to the supporting
plate 8 by means of welding, and the like. This solution, however,
brings about an increase in the number of parts and a higher
cost.
[0032] As a solution, in this embodiment, the radiating fins 85 are
constituted by cut-and-raised pieces that are formed in the
supporting plate 8. According to this arrangement, the radiating
fins made of separate members are not required, and the cost can be
reduced. In addition, the heat transmitting area of the supporting
plate 8 is narrowed due to the presence of the holes 85a that are
formed as a result of cutting-and-raising of the radiating fins 85.
Therefore, the amount of heat transmission to the housing 1 is
further reduced, and the temperature rise in the housing 1 can more
effectively be limited.
[0033] A description has so far been made of an embodiment of this
invention. This invention is, however, not limited to the
above-mentioned embodiment. For example, although in the
above-mentioned embodiment, the outdoor air is supplied to the
burner 4 as combustion air, it is also possible to supply the
indoor air to the burner 4 as combustion air.
* * * * *