Information
-
Patent Grant
-
6478577
-
Patent Number
6,478,577
-
Date Filed
Thursday, August 24, 200024 years ago
-
Date Issued
Tuesday, November 12, 200222 years ago
-
Inventors
-
Original Assignees
-
Examiners
Agents
- Watts, Hoffmann, Fisher & Heinke Co.
-
CPC
-
US Classifications
Field of Search
US
- 431 286
- 431 353
- 431 354
- 239 434
- 239 552
- 239 559
- 239 560
- 239 561
- 239 567
- 239 548
- 239 556
- 239 558
-
International Classifications
-
Abstract
A burner nozzle includes a burner tube that extends along a central axis and has an inlet end portion for receiving combustible gas and air. The burner tube extends along the central axis from the inlet end portion to an outlet end portion for releasing a mixture of gas and air. A curved head with a plurality of openings and an imperforate portion is connected to the outlet end portion. The openings and imperforate portion of the curved head create a transverse flow of gas and air out of the curved head to produce a shaped flame. A burner assembly may include a combustion tube in which the burner nozzle is disposed and connected. The burner nozzle is used in a method of widening and shaping a flame.
Description
FIELD OF INVENTION
This invention relates to burners and, more specifically, to gas burners suitable for use in appliances and the like.
BACKGROUND OF THE INVENTION
Burners are used, for example, in apparatuses including furnaces and appliances such as clothes dryers. A principle component of burners is a nozzle typically in the form of a venturi tube. Combustible gas is fed into the nozzle and entrains air into the nozzle. The air and gas is mixed in the venturi and the mixture emerges from the outlet end. An igniter may be attached directly to the venturi tube in front of the outlet opening in alignment with a longitudinal axis along which the nozzle extends and ignites the mixture as it leaves the outlet, thereby creating flame which produces heat that is utilized by the apparatus.
In furnaces, a plurality of burner nozzles are typically arranged side-by-side and are designed for cross-ignition of the gas in adjacent nozzles. One conventional nozzle has two plenum chambers located at an outlet end of the venturi tube. Each plenum chamber has a thin outlet slit along its side edges. Flame released from the side outlet slits of one nozzle ignites gas from an adjacent nozzle.
Clothes dryer burners are horizontally fired into ducts of the dryer. The ducts shield the open flame and force the heated gases in the desired direction. The burner may include an attachment known as a flame spreader which is separately formed from the nozzle, mounted such as by welding to the nozzle and axially spaced from the outlet opening of the nozzle. One function of a flame spreader is to prevent upward lifting or curling of the flame as it travels horizontally. The flame spreaders are disposed in the flame and thus, are exposed to relatively high temperatures. This requires the flame spreaders to be fabricated from metals or coated with materials which can withstand this high temperature environment.
Conventional gas dryer burner nozzles typically produce flame having a length of, for example, about one foot. However, space is limited in the dryer. Long flame lengths may result in inefficient heat transfer between the flame and air inside the duct work, overheating of the duct work, or an increase in the cost of the dryer due to the use of enough duct work to accommodate the long flame. Heated gases from the horizontal flame are typically directed through a 90° elbow, generally vertically to another 90° elbow, through a screen and then into a rotatable drum in which clothes are dried.
Typical gas dryer burner nozzles can be difficult and relatively expensive to manufacture. Such burner nozzles are fabricated by a practice of forming a venturi tube from tubing and welding a stamped flame spreader to an end of the formed burner tube.
SUMMARY OF THE INVENTION
The present invention is directed to a burner nozzle for producing a shaped and/or shortened flame for efficient heat transfer. The burner is characterized by a curved head with an imperforate portion for shaping the flame. The burner is particularly well suited for use in clothes dryers where a flame that is spread out transverse to the direction of gas flow and that has a reduced length, is desired. A burner nozzle produced in accordance with the present invention reduces the fabrication costs and results in efficient heat transfer.
In general, the invention is a burner nozzle that includes a burner tube that extends along a central axis and has an inlet end portion for receiving combustible gas and air and an outlet end portion for releasing a mixture of the gas and air. A main gas flow passage extends along the central axis between the inlet end portion and the outlet end portion. A curved head that has a plurality of openings is connected to the outlet end portion. The curved head includes an imperforate portion that is disposed near the central axis. The plurality of openings and imperforate portion of the curved head create a transverse flow of the mixture of gas and air out of the curved head to produce a shaped flame that results in efficient heat transfer between the flame and air inside a heat-receiving member, such a duct, located downstream of the outlet end.
As to the specific features of the burner nozzle, the burner tube may include wing portions that extend laterally from the burner tube for attachment to the duct of a dryer. The curved head may comprise a curved portion defined by a portion of a sphere, a cylindrical portion that extends from said curved portion and a mounting flange that extends transversely from said cylindrical portion.
The curved head may be hemispherical in shape with round openings evenly spaced about the circumference of the curved head. The plurality of openings in the curved head may be arranged in two rows. The holes of the first row are circumferentially spaced around the head near a base of the head. The holes of the second row are circumferentially spaced around the head between the first row of openings and a tip of the burner located at the central axis. The openings of the first row near the base of the curved head may be larger than the openings of the second row that are between the first row and the tip. The head may also include a central opening at the tip, along the central axis.
A burner assembly may be formed by fastening the inventive burner nozzle in the interior of a combustion tube. The combustion tube may be comprised of two articles formed of stamped metal or a single rolled form. Preferably, in the case of a clothes dryer application, only a single burner nozzle is used in the burner assembly. The heat receiving member or duct comprises a passageway having a portion with a shape (e.g., circular) that corresponds to the elongated shape of the flame.
A portion of the mixture of gas and air may be passed through an opening in the head that encompasses the central axis. The diameter of the opening that encompasses the central axis can be varied to elongate or shorten the length of the flame.
A general method of producing a shaped flame from a burner nozzle comprises directing combustible gas and air into an inlet end portion of a burner tube that extends along a central axis. The gas and air are mixed in the burner tube. The gas and air are directed along the central axis toward and outlet end portion of the burner. A portion of the gas and air are diverted by an imperforate portion of a curved shaped head at the outlet end portion away from the central axis. The gas and air are passed through circumferentially spaced openings in the curved head. The mixture is ignited to produce a shaped flame. When the gas and air are passed through the circumferentially spaced openings, the head may direct a portion of the gas and air in a direction that is transverse to the central axis.
The present invention offers numerous advantages over prior gas dryer burners. The imperforate portion in conjunction with the openings in the curved head enable elongation of the flame transverse to the central axis of the burner nozzle. This results in a flame that has an ideal shape when used with duct work having a corresponding passageway (e.g., a circular duct). There is an efficient heat transfer between the elongated transverse flame and the air in the duct since there is less wasted space compared to the use of a burner that produces a flame with a small diameter in a duct that has a large diameter. Alternatively, or in addition to the flame shaping feature, the burner nozzle may produce a shortened flame having a length of, for example, about one half of conventional burner nozzles used in clothes dryers. In vertical firing applications there is a shorter distance between the end of the flame and the entry to the drum than in horizontal firing applications. Therefore, a flame that is too long may overheat the duct work, the screen or articles in the dryer.
Other embodiments of the invention are contemplated to provide particular features and structural variance of the basic elements. The specific embodiments referred to, as well as possible variations in the various features and advantages of the invention, will become better understood from the accompanying drawings together with the detailed description that follows.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1
is a perspective view of a gas burner nozzle constructed in accordance with the present invention;
FIG. 2
is a front elevational view of the gas burner nozzle shown in
FIG. 1
;
FIG. 3
is a top plan view of a burner nozzle constructed in accordance with the present invention;
FIG. 4
is a cross-sectional view as seen along the plane represented by line
4
—
4
in
FIG. 3
; and,
FIG. 5
is a perspective view of a gas burner assembly constructed in accordance with one of the embodiments of the present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Referring now to the drawings and to
FIG. 1
, in particular, one embodiment of a burner nozzle constructed in accordance with the present invention is designated generally by the reference numeral
10
. The burner nozzle
10
includes a burner tube
18
that extends along a central axis C. The burner nozzle
10
has an inlet end portion
20
for receiving combustible gas and air and an outlet end portion
22
for releasing a mixture of the gas and air. A main gas flow passageway
26
extends along the central axis between the inlet end portion
20
and the outlet end portion
22
. A heat receiving member (not shown), such as a duct leading to a drum of a clothes dryer is disposed downstream of the outlet end portion
22
relative to a direction of flow of the mixture of gas and air. A curved head
30
is connected to the outlet end portion
47
of the tube
18
. The curved head has a plurality of openings
32
spaced around its circumference
34
near a base
35
of the curved head
30
and an imperforate portion
36
that extends from the plurality of openings
32
nearly to a tip
64
of the curved head
30
. The imperforate portion
36
creates a transverse flow of the mixture of gas and air out of the plurality of openings
32
to produce a shaped flame. In the exemplary embodiment, the curved head includes an optional central hole
37
. The size of the central hole
37
dictates flame length and width. Referring to
FIG. 4
, the curved head also includes a mounting flange
39
that extends around the base
35
of the curved head
30
.
Referring to
FIGS. 1 and 3
, a gas supply opening
38
at the inlet end portion
20
of the burner tube
18
is sized so that the burner tube may be connected in a conventional manner to a gas valve (not shown). The term “gas” is used herein in reference to a combustible fuel in gaseous form. It will be appreciated that any suitable gaseous combustible fuel may be used. For example, natural gas, propane, butane, and other gas mixtures may be suitable gaseous fuels. Air supply openings
40
are formed at the inlet end portion of the burner tube. Those skilled in the art would appreciate, in view of this disclosure, that the size of the air supply openings may be adjusted as desired to be fixed upon fabrication or may be variable using a shutter, depending upon the air flow requirements of the particular application. As the gas flows by the air supply openings it entrains the air into the burner tube.
Referring to
FIGS. 1 and 3
, the main passageway
26
has a shape that forms a venturi in a well known manner. The burner tube
18
includes a first transition
42
, where the diameter of the gas supply opening is gradually reduced to the inner diameter
44
(shown in
FIG. 3
) of the burner tube
18
. The main gas flow passageway
26
extends from the first transition
42
to a second transition
46
, where the inner diameter of the burner tube
18
gradually increases to the large inner diameter
48
(shown in
FIG. 4
) of the outlet portion
47
of the burner tube. Referring to
FIG. 4
, a head mounting portion
49
is defined around the circumference of the outlet portion
47
of the burner tube. The head mounting portion
49
defines a narrow cavity
51
in the outlet portion
47
that has a diameter that is larger than the diameter
48
of the rest of the burner tube
18
. The cavity
51
of the head mounting portion
49
is sized to accept the mounting flange
39
of the head
30
.
The burner tube
18
may be fabricated from two sheet metal halves
50
a,
50
b
or from one single sheet. In the preferred embodiment, the two halves
50
a,
50
b
are mirror images of one another. The wing-shaped members
52
a,
52
b
are preferably formed integrally with and flank the burner tube
18
. This facilitates cost effective fabrication since the same die is used to fabricate each sheet metal half. The first step is to size each sheet metal half for the appropriate height and width. The air supply openings in the inlet end portion are formed in each sheet metal half. The sheet is then stamped and die configured to form integral “half sections”, each containing the features of the burner tube
18
. The two sheet metal halves are then joined together and form a gas tight seam.
Referring to
FIGS. 1
,
2
and
4
, the burner tube
18
may be formed from two stamped sheet metal halves
50
a,
50
b.
The sheet metal halves
50
a,
50
b
each include wings
52
a,
52
b
that are spot welded or mechanically fastened together to form the burner tube
18
. In one embodiment, BTM Company's Tog-L-Loc sheetmetal joining system is used to fasten the sheetmetal halves
50
a,
50
b
together to form the burner tube
18
. The wings
52
a,
52
b
are formed integrally with the burner tube and extend outwardly from the main gas flow passageway
26
. The wings
52
a,
52
b
may be used to mount the burner nozzle
10
to an optional outer combustion tube
12
, as shown in FIG.
5
. Although the sheet metal halves can be constructed to form a cavity in each of the wings
52
a,
52
b
that has an opening near the head for a portion of the mixture of gas and air to exit, none of the mixture of gas and air is permitted to exit through the wings
52
a,
52
b
in the exemplary embodiment.
Referring to
FIG. 4
, the curved head
30
of the exemplary embodiment includes a hemispherical portion
54
, a cylindrical portion
56
that extends from the hemispherical portion, and a mounting flange
39
that extends transversely from the cylindrical portion
56
around the circumference of the cylindrical portion
56
. The outer diameter of the cylindrical portion
56
is sized to fit within the inner diameter
48
of the outlet end portion
22
of the burner tube
18
. The curved head
30
is installed in a sheet metal half
50
a
of the burner tube
18
, with a portion of the mounting flange
39
of the head
30
disposed in the cavity
51
in the tube sheet metal half
50
a.
The mounting cavity
51
in the second sheet metal tube half
50
b
is placed over the exposed portion of the mounting flange
39
. The first and second sheet metal halves
50
a,
50
b
are then secured together to capture the mounting flange
39
in the mounting cavity
51
between the first and second halves. In the exemplary embodiment, the cylindrical portion
56
of the head
30
is disposed within the burner tube
18
and the hemispherical portion
54
of the head
30
extends out of the burner tube
18
.
The hemispherical portion
54
of the head
30
includes a plurality of openings
32
about the circumference
34
of the head
30
near the base
35
of the head. Referring to
FIGS. 1 and 3
, the plurality of openings
32
is comprised of a row
60
of large round openings
61
, evenly spaced around the head
30
near the base
35
of the head
30
and a row
62
of smaller round openings
63
evenly spaced around the head
30
between the row
60
of large openings
61
and a tip
64
of the head
30
. In the exemplary embodiment, each of the openings
32
of the curved head
30
are round. The round openings
32
in the head are created by punching appropriately shaped holes in a flat piece of stock that become substantially round when the flat piece of stock is formed into a curved head. The punched openings become round as the flat piece of stock is formed into a curved head. It should also be readily apparent to those skilled in the art that the openings
32
can be drilled in the curved head
30
after the flat piece of stock is formed into a curved head.
The imperforate portion
36
of the head is defined by the area of the hemispherical portion
54
of the curved head
30
between the row
62
of small round openings
63
and the central hole
37
in the tip
64
of the head (shown by dotted lines in
FIG. 2
) or from the row
62
up to and including the tip
64
at axis C, if no hole
37
is used. The imperforate portion
36
inhibits a portion of the mixture of gas and air from exiting the burner nozzle along the central axis C and directs a portion of the mixture of gas and air out the plurality of openings
32
in a direction transverse to the central axis C of the burner nozzle
10
to produce a shaped flame. The shape of the flame can be modified by modifying the size of the central hole
37
. Increasing the size of the central hole
37
increases the length of the flame and decreases the diameter of the flame. Decreasing the size of the central hole
37
decreases the length of the flame and increases the diameter of the flame. The central hole
37
can be eliminated to produce a short flame that has a wide diameter. The size, shape and pattern of the plurality of holes
32
about the circumference
34
of the head can also be adjusted to adjust the shape of the flame produced by the burner. For example, the holes of the second row can be larger than the holes of the first row or the plurality of holes
32
can be arranged in a non-circular pattern.
Referring to
FIG. 5
, the burner
10
of the present invention may optionally be connected to an outer combustion tube
12
to form a burner assembly
16
. The outer combustion tube
12
surrounds an interior region
14
in which a burner nozzle
10
is disposed. The burner assembly
16
, as shown in
FIG. 5
, is suitable for use with both horizontal and vertical flow of the mixture of gas and air. The burner nozzle
10
of invention is designed to be used in vertical and horizontal firing where the combustion tube
12
and duct (not shown) have a circular shape. A short combustion tube and duct having a large diameter is accommodated by a burner tube having a small central hole
37
or no central hole, since the flame produced is short and wide. A longer combustion tube and duct having a smaller diameter is accommodated by a burner tube having a larger central hole, since the flame produced is longer and narrower.
When a combustion tube
12
is used, it may be formed of galvanized or aluminized steel. The curved head
30
may be formed of any suitable material, such as aluminized or stainless steel. The combustion tube
12
is preferably formed of two articles of stamped metal, which simplifies and reduces the cost of manufacture.
Referring to
FIGS. 1-4
, regarding operation of the burner, to produce a shaped flame from the burner nozzle, combustible gas is fed into the gas opening
38
of the burner tube
18
from a gas valve (not shown) in a manner known to those skilled in the art. Air is entrained by the gas into the burner tube through the air supply openings
40
. The flow of gas and air is directed into the burner tube
18
that extends along the central axis C. The air and gas is mixed in the burner tube venturi and is directed along the central axis C toward the outlet end portion
47
of the burner tube
18
. The mixture of gas and air reaches the curved head
30
of the burner nozzle
10
and a portion of the mixture is diverted by the imperforate portion
36
of the curved head away from the central axis C. A portion of the gas and air passes through the central opening
37
and the remainder of the gas and air mixture is passed through the plurality of openings
32
in a direction transverse to the central axis C. The mixture of gas and air is then ignited to produce a shaped flame, such as that shown in FIG.
4
.
Referring to
FIG. 4
, the shape of the flame
80
formed by the burner nozzle of the exemplary embodiment is relatively short and wide. A portion of the mixture of gas and air exits the plurality of openings
32
transverse to the central axis C and is ignited to produce a wide flame portion
82
. The shape of the wide portion
82
resembles petals of a flower that extend from a center of the flower. A central flame portion
84
is produced by igniting the portion of the mixture of gas and air that exits the burner nozzle
10
through the central hole
37
. The length and width of the flame
80
can be adjusted by varying the size of the central hole
37
. The length of the flame is increased and the width of the flame is reduced by increasing the size of the central hole. The flame
80
is shortened and the width of the flame is increased by reducing the size of the central hole
37
.
Although the invention has been described in its preferred form with a certain degree of particularity, it will be understood that the present disclosure of the preferred embodiments has been made only by way of example and that various changes may be resorted to without departing from the true spirit and scope of the invention as hereafter claimed.
Claims
- 1. A burner nozzle for producing a shaped flame for efficient heat transfer, comprising:a burner tube that extends along a central axis, including an inlet end portion for receiving combustible gas and air and an outlet end portion for releasing a mixture of said gas and said air, said outlet end portion includes a head mounting recess; and a curved head in communication with said outlet end portion, said curved head including a transversely extending mounting flange, said mounting flange being constrained within said head mounting recess, said head having a plurality of openings and an imperforate portion surrounding said central axis, said plurality of openings comprise a first row of openings circumferetially spaced about a circumference of said head and a second row of openings circumferentially spaced about said circumference of said head between said first row of openings and a tip of said burner located at said central axis wherein said openings and said imperforate portion create a transverse flow of said mixture out of said head to produce a shaped flame.
- 2. A burner nozzle for producing a shaped flame for efficient heat transfer, comprising:a burner tube that extends along a central axis, including an inlet end portion for receiving combustible gas and air and an outlet end portion for releasing a mixture of said gas and said air, said outlet end portion includes a head mounting recess; and a curved head in communication with said outlet end portion, said curved head including a transversely extending mounting flange, said mounting flange being constrained within said head mounting recess, said head having a plurality of openings, a central opening that encompasses said central axis, and an imperforate portion surrounding said central axis, wherein said imperforate portion is defined by an area between said central opening and said plurality of opening, said plurality of openings and said imperforate portion create a transverse flow of said mixture out of said head to produce a shaped flame.
- 3. A burner nozzle for producing a shaped flame for efficient heat transfer, comprising:a burner tube that extends along a central axis, including an inlet end portion for receiving combustible gas and air and an outlet end portion for releasing a mixture of said gas and air, said outlet end portion includes a head mounting recess; and a hemispherical head having a transversely extending mounting flange constrained within said head mounting recess to connect said head to said tube, said hemispherical head having a plurality of openings and an imperforate portion surrounding said central axis, said openings being circumferentially spaced about a circumference of said hemispherical head to create a transverse flow of said mixture out of said head to produce a shaped flame.
- 4. The burner nozzle of claim 3 wherein said openings are circular.
- 5. The burner nozzle of claim 3 comprising a central opening that encompasses said central axis, wherein said imperforate portion is defined by an area between said central opening and said plurality of openings.
- 6. A method of producing a shaped flame from a burner nozzle, comprising the steps of:directing combustible gas and air into an inlet end portion of a burner tube that extends along a central axis; mixing said gas and said air in said burner tube to create a mixture of gas and air; directing said gas and said air along the central axis toward an outlet end portion of said burner tube having a head mounting recess; deflecting a portion of said gas and said air by contact with an imperforate portion of a head having a hemispherical shaped portion and a mounting flange that is constrained within said head mounting recess to divert a portion of said gas and said air away from said central axis; passing said gas and said air through circumferentially spaced openings in said head; and igniting said mixture to produce a shaped flame.
- 7. The method of claim 6 wherein said step of passing said gas and said air through said head directs a portion of said gas and said air in a direction that is transverse to said central axis.
- 8. A burner nozzle for producing a shaped flame for efficient heat transfer, comprising:a burner tube that extends along a central axis, including an inlet end portion for receiving combustible gas and air and an outlet end portion for releasing a mixture of said gas and said air; wing portions extending laterally from said burner tube; and a curved head in communication with said outlet end portion, said curved head having a plurality of openings and an imperforate portion surrounding said central axis, wherein said openings and said imperforate portion create a transverse flow of said mixture out of said head to produce a shaped flame.
- 9. The burner nozzle of claim 8 wherein said head comprises a curved portion and a cylindrical portion, said head being curved from a tip of said head to said cylindrical portion.
- 10. A burner nozzle for producing a shaped flame for efficient heat transfer, comprising:a burner tube that extends along a central axis, including an inlet end portion for receiving combustible gas and air and an outlet end portion for releasing a mixture of said gas and said air; and a curved head including a curved portion defined by a portion of a sphere, a cylindrical portion extending from said curved portion and a mounting flange extending transversely from said curved portion said mounting flange being connected to said outlet end portion to connect said curved head to said burner tube, said curved head having a plurality of openings and an imperforate portion surrounding said central axis, wherein said openings and said imperforate portion create a transverse flow of said mixture out of said head to produce a shaped flame.
- 11. The burner nozzle of claim 10 wherein said head is curved from a tip of said head to said cylindrical portion.
- 12. A burner nozzle for producing a shaped flame for efficient heat transfer, comprising:a burner tube that extends along a central axis, including an inlet end portion for receiving combustible gas and air and an outlet end portion for releasing a mixture of said gas and air; and a hemispherical head in communication with said outlet end portion, said hemispherical head having a plurality of openings and an imperforate portion surrounding said central axis, said openings comprise a first row of openings evenly spaced about the circumference of said head and a second row of smaller openings evenly spaced about the circumference of said head between said first row of openings and a tip of said burner located at said central axis to create a transverse flow of said mixture out of said head to produce a shaped flame.
- 13. A burner nozzle for producing a shaped flame for efficient heat transfer, comprising:a burner tube that extends along a central axis, including an inlet end portion for receiving combustible gas and air and an outlet end portion for releasing a mixture of said gas and air; and a hemispherical head comprising a hemispherical portion, a cylindrical portion extending from said hemispherical portion and a mounting flange extending transversely from said cylindrical portion connected to said outlet end portion to connect said head to said tube, said head having a plurality of openings and an imperforate portion surrounding said central axis, said openings being circumferentially spaced about a circumference of said hemispherical head to create a transverse flow of said mixture out of said head to produce a shaped flame.
- 14. The burner nozzle of claim 13 wherein said mounting flange is captured by a mounting cavity in said burner tube.
- 15. A burner assembly for producing a shaped flame for efficient heat transfer, comprising:a combustion tube surrounding an interior region; a burner nozzle disposed in said interior region and connected to said combustion tube, said burner nozzle comprising a burner tube that extends along a central axis, including an inlet end portion for receiving combustible gas and air and an outlet end portion for releasing a mixture of said gas and said air; and a curved head in communication with said outlet end portion, said curved head having a plurality of circumferential openings, a central opening that encompasses said central axis, and an imperforate portion surrounding said central axis, wherein said imperforate portion is defined by an area between said central opening and said plurality of openings, said circumferential openings create a transverse flow of said mixture out of said head to produce a shaped flame.
- 16. A burner assembly for producing a shaped flame for efficient heat transfer, comprising:a combustion tube surrounding an interior region; a burner nozzle disposed in said interior region and connected to said combustion tube, said burner nozzle comprising a burner tube that extends along a central axis and a wing portion, said burner tube including an inlet end portion for receiving combustible gas and air and an outlet end portion for releasing a mixture of said gas and said air, said mixture of gas and air is prevented from exiting through said wing portion; and a curved head in communication with said outlet end portion, said curved head having a plurality of openings and an imperforate portion surrounding said central axis, said openings create a transverse flow of said mixture out of said head to produce a shaped flame.
- 17. A method of producing a shaped flame from a burner nozzle, comprising the steps of:directing combustible gas and air into an inlet end portion of a burner tube that extends along a central axis; mixing said gas and said air in said burner tube; directing said gas and said air along the central axis toward an outlet end portion of said burner tube; deflecting a first portion of said gas and said air by contact with an imperforate portion of a curved shaped head at said outlet end portion to divert a portion of said gas and said air away from said central axis; passing a second portion of said mixture of gas and air through a central opening in said curved head that encompasses said central axis to elongate a shaped flame; passing a third portion of said gas and said air through circumferentially spaced openings in said curved head; and igniting said mixture to produce said shaped flame.
- 18. A method of producing a shaped flame from a burner nozzle, comprising the steps of:selecting a curved shaped head from a series of curved shaped heads for use in said burner nozzle, said series of heads having central openings with varying diameters to thereby adjust a length of a shaped flame based on the diameter of the central opening of said selected head; directing combustible gas and air into an inlet end portion of a burner tube that extends along a central axis; mixing said gas and said air in said burner tube; directing said gas and said air along the central axis toward an outlet end portion of said burner tube; deflecting a portion of said gas and said air by contact with an imperforate portion of a curved shaped head at said outlet end portion to divert a portion of said gas and said air away from said central axis; passing said gas and said air through circumferentially spaced openings in said curved head; and igniting said mixture to produce said shaped flame.
- 19. A burner nozzle for producing a shaped flame, comprising:a burner tube that extends along a central axis, including an inlet end portion for receiving combustible gas and air and an outlet end portion for releasing a mixture of said gas and air; and a curved head comprising a curved portion, a cylindrical portion extending from said curved portion and a mounting flange extending transversely from said cylindrical portion connected to said outlet end portion to connect said head to said burner tube.
- 20. The burner nozzle of claim 19 wherein said burner tube includes a head mounting recess that defines a cavity that accepts said mounting flange.
- 21. The burner nozzle of claim 19 wherein said burner tube includes a first transition where the inlet end of the burner tube is reduced to an inner diameter of the burner tube and a second transition where the inner diameter is increased to the outlet end portion.
US Referenced Citations (22)
Foreign Referenced Citations (2)
Number |
Date |
Country |
142759 |
May 1920 |
GB |
374590 |
Jun 1932 |
GB |