U.S. patent application number 10/350147 was filed with the patent office on 2004-07-15 for hot air heater and method of operating same.
This patent application is currently assigned to INTERNATIONAL THERMAL INVESTMENTS, LTD.. Invention is credited to Robinson, Edgar C..
Application Number | 20040134481 10/350147 |
Document ID | / |
Family ID | 32660906 |
Filed Date | 2004-07-15 |
United States Patent
Application |
20040134481 |
Kind Code |
A1 |
Robinson, Edgar C. |
July 15, 2004 |
Hot air heater and method of operating same
Abstract
A hot air heater having a burner tube surrounding a combustion
area. The combustion gases travel from the burner tube through
first and second circumferential and concentric annuluses
surrounding the burner tube. Cool ambient air used for heating is
blown over the outside surfaces of the annuluses and heat from the
combustion gases is transferred to the ambient air used for heating
by way of the surfaces of the jackets defining the annuluses.
Inventors: |
Robinson, Edgar C.;
(Vancouver, CA) |
Correspondence
Address: |
John Russell Uren, P. Eng.
Suite 202
1590 Bellevue Avenue
West Vancouver
V7V 1A7
CA
|
Assignee: |
INTERNATIONAL THERMAL INVESTMENTS,
LTD.
|
Family ID: |
32660906 |
Appl. No.: |
10/350147 |
Filed: |
January 22, 2003 |
Current U.S.
Class: |
126/110D ;
126/114 |
Current CPC
Class: |
F24H 3/065 20130101 |
Class at
Publication: |
126/110.00D ;
126/114 |
International
Class: |
F24H 003/02 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 14, 2003 |
CA |
2,416,234 |
Claims
I claim:
1. Method of heating cool air, said method comprising inletting
combustion air used for combustion within a burner, combusting said
air with a fuel to produce hot combustion gases within a combustion
area, passing said combustion gas from said combustion area into a
first and second jacket surrounding said combustion area, each of
said first and second jackets being defined by surfaces and heating
cool ambient air passing over said surfaces of said first and
second jackets.
2. Method as in claim 1 wherein said combustion gases are passed
through an exhaust communication port between said first and second
jackets.
3. Method as in claim 2 and further comprising passing said cool
ambient air over the outsides of said first and second jackets by a
fan.
4. Method as in claim 3 and further comprising exhausting said
combustion gases following passage through said second jacket.
5. Method as in claim 4 wherein said cool ambient air is heated as
said ambient air moves over said surfaces within a heater annulus
surrounding said jackets.
6. Method as in claim 5 wherein said first and second jackets are
formed to be concentric with said combustion area.
7. A hot air heater comprising a combustion area for combustion of
air and fuel, a first jacket surrounding said combustion area for
allowing combustion gases to circulate therethrough, a second
jacket outside said first jacket to allow said combustion gases to
circulate therethrough and a combustion gas outlet to allow said
combustion gases to exhaust from said hot air heater following
passage through said first and second jackets.
8. A hot air heater as in claim 7 wherein said combustion area is
within a burner tube.
9. A hot air heater as in claim 8 wherein said first and second
jackets are concentric with said burner tube.
10. A hot air heater as in claim 9 and further comprising an
exhaust communication port between said first and second
jackets.
11. A hot air heater as in claim 10 and further comprising an
exhaust port to exhaust said combustion gases from said second
jacket.
12. A hot air heater as in claim 11 and further comprising a source
of cool air for heating said cool air by said combustion gases.
13. A hot air heater as in claim 12 wherein said first and second
jackets are defined by surfaces and further comprising a fan to
blow said cool air over said surfaces of said first and second
jackets.
14. A hot air heater as in claim 13 wherein said cool air is heated
within a heater annulus and further comprising an outlet for said
heated ambient air from said heater annulus.
Description
[0001] This invention relates to a diesel powered heater and, more
particularly, to a diesel powered heater used for heating ambient
air by utilising an increased surface area for heat transfer.
BACKGROUND OF THE INVENTION
[0002] In our U.S. Pat. No. 6,085,738, the contents of which are
incorporated herein by reference, there is disclosed a burner using
diesel fuel which utilises an atomising nozzle and which is
operable to heat hot water which hot water is used for heating the
living areas of a boat, recreational vehicle or the like. The hot
water is circulated through the burner and thence may be directed
to a heat exchanger or used directly in radiators for allowing the
heat to emanate by radiation in the living environment. The burner
there described in sold under the trademark HURRICANE (Trademark)
by International Thermal Research of Richmond, British Columbia,
Canada.
[0003] The use of hot water for living environment heating is, of
course, known and attractive because of the absence of hot air and
a more uniform temperature achieved over time. However, hot water
heating also requires hardware including radiators and associated
plumbing components to allow the hot water to circulate within the
heating system without leaks. This entails costs. In many
applications, it is not particularly desirable to incur such costs
and hot water heating may be supplemented or replaced with hot air
heated by the burner.
[0004] In order to heat the air being passed over the burner and
then to distribute the heated air to a living environment in a hot
air heater, it is necessary to transfer the heat generated by the
burner to the cooler ambient air passing over the heated combustion
chamber without commingling the ambient air with the air used for
combustion. This is so because the combustion air contains carbon
monoxide and other byproducts which are harmful if ingested. Thus,
heat transfer efficiency between the combustion air and the ambient
air is a principal consideration.
[0005] In a known hot air heater, the cool ambient air used for
heating passes over the outside of the combustion chamber. A
plurality of fins are constructed which extend into the combustion
chamber through the cylinder surrounding the combustion area, which
fins are exposed on the outside to the cool ambient air passing
thereover. The objective, of course, is to transfer the heat
produced within the combustion chamber to the air passing over the
fins outside the combustion chamber. The use of the fins increases
the surface area which is exposed to both the combustion air and to
the ambient air to be heated. Thus, heat transfer is improved
between the combustion chamber and the cool ambient air using for
heating the living areas. Fins are costly to produce and much
material is used in their construction. Their efficiency, while
good, is not particularly high. These characteristics are
disadvantageous.
SUMMARY OF THE INVENTION
[0006] According to one aspect of the invention, there is provided
a method of heating cool air, said method comprising inletting
combustion air used for combustion within a burner, combusting said
air with a fuel to produce hot combustion gases within a combustion
area, passing said combustion gas from said combustion area into a
first and second jacket surrounding said combustion area, each of
said first and second jackets being defined by surfaces and heating
cool ambient air passing over said surfaces of said first and
second jackets.
[0007] According to a further aspect of the invention, there is
provided a hot air heater comprising a combustion area for
combustion of air and fuel, a first jacket surrounding said
combustion area for allowing combustion gases to circulate
therethrough, a second jacket outside said first jacket to allow
said combustion gases to circulate therethrough and a combustion
gas outlet to allow said combustion gases to exhaust from said hot
air heater following passage through said first and second
jackets.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0008] Specific embodiments of the invention will now be described,
by way of example only, with the use of drawings in which:
[0009] FIG. 1 is a diagrammatic and partial cross-sectional view of
a hot air heater according to the invention and illustrating the
combustion gas jackets surrounding the burner assembly; and
[0010] FIG. 2 is an end view of the hot air heater of FIG. 1.
DESCRIPTION OF SPECIFIC EMBODIMENT
[0011] Referring now to the drawings, a hot air heater according to
the invention is generally illustrated at 100 in FIG. 1. It
comprises a burner generally illustrated at 101 which burner is of
the air aspirated type and which utilises air under pressure to
draw fuel into the nozzle 104 and in respect of which the flame 102
combusts the air and fuel within a burner tube 103 which burner
tube 103 has an open end 110 opposed to the end of the burner tube
103 holding the nozzle 104. Such a burner is described in greater
detail in our aforementioned U.S. Pat. No. 6,085,738 and associated
U.S. Pat. No. 5,391,075, the latter of which the contents are also
incorporated herein by reference.
[0012] A first jacket 111 surrounds the burner tube 103. First
jacket 111 defines a first annulus 112 surrounding the burner tube
103 with an outlet for the combustion gases to allow the combustion
gases to enter a second jacket 113 which second jacket 112 defines
a second annulus 114 to allow the circulation of gases entering
from the first annulus 112. An exhaust gas communication port 120
extends between the first and second annuluses 112, 114 to allow
the exhaust or combustion gases to pass from the first annulus 112
within first jacket 111 to second annulus 114 within second jacket
113. An exhaust port 122 communicating with second annulus 114
provides venting for the hot combustion or exhaust gases following
their circulation through second annulus 114.
[0013] A plurality of vanes 123 conveniently extend partially
around the inside circumference of the first burner jacket 111. The
vanes 123 provide a swirling passageway for the combustion gases as
they travel from the burner tube 103 into and through the first
jacket 111.
[0014] A heater annulus 131 is formed to surround the burner 101
and first and second jackets 111, 113. The heater annulus 131 is
intended to provide a passageway for ambient and cool air inletted
to the heater 100. A fan, diagrammatically illustrated at 124,
blows cool ambient air over the circumferences of the first and
second jackets 111, 114 and which air is traveling within the
heater annulus 131 to an outlet 130 provided in the heater annulus
131. The heated ambient air then is ducted or otherwise conveyed to
the areas of the vessel or vehicle where it is used for heating
purposes as is usual.
OPERATION
[0015] In operation, the burner 101 commences operation by way of
manual initiation or, if a thermostat (not illustrated) is intended
to automatically initiate the operation of burner 101, by way of
such thermostat falling below a desired temperature as the user may
select. Air is provided under pressure to the burner 101 and such
air is used to draw in the necessary fuel. An igniter 105 ignites
the mixed air and fuel and combustion is initiated with the
resulting combustion flame 102.
[0016] The resulting combustion gases travel out the open end of
burner tube 103 and into first annulus 112 defined by the outside
of the burner tube 103 and the inside of first jacket 111, thence
to exhaust gas communication port 120 and into second annulus 114
and eventually to exhaust port 122 where the combustion gases are
normally ducted to the atmosphere.
[0017] During the travel of the exhaust gases through first and
second annuluses 112, 114, the gases heat the inside and outside
circumferences or surfaces of each jacket 111, 113. This surface
area provides a substantial heat transfer area for transferring
heat received from the combustion gases and passed to the
circumferences of each jacket 111, 112 to the ambient cool air
blown over the surfaces as will be explained.
[0018] Fan 124 commences operation when manually initiated or,
again, under the control of a thermostat or other temperature
initiation or timing device. Fan 124 has inletted cool air from the
ambient surroundings and such air is blown over the outside
circumference of first jacket 111 and over the inside and outside
circumferences of second jacket 113 as it travels within heater
annulus 131. The heat produced by the exhaust gases is thereby
transferred from the circumferential surfaces of the first and
second jackets 111, 113, respectively to the cool ambient air which
air, now heated, leaves by way of outlet port 130 and which air is
used for heating purposes as may be desired.
[0019] Additional heat transfer area may conveniently be provided
by providing fins which extend from the two annuluses 112, 114
though the circumferences of the jackets 111, 113, if desired.
However, it is presently thought the addition of such fins may be
unnecessary given the satisfactory heat transfer efficiency
obtained with the invention as described.
[0020] Many modifications will readily occur to those skilled in
the art to which the invention relates and the specific embodiments
described herein should be taken as illustrative of the invention
only and not as limiting its scope as defined in accordance with
the accompanying claims.
* * * * *