FIELD OF THE INVENTION
[0001] The present invention relates to burner arrangements and in particular, but not exclusively,
to a fuel injection assembly for a gas burner in which a fuel is injected from a manifold
into the inlet of at least one associated burner element. The present invention also
relates to methods and materials used to produce such burner arrangements.
BACKGROUND TO THE INVENTION
[0002] Some prior art burners are built up from a series of blade elements spaced apart
in a parallel array. Many such prior art burners consist basically of a gas injector
through whom a fuel gas such as methane, butane or propane is injected in a pressurized
flow into a mixing tube. The tube often comprises a venturi and the flow of fuel gas
is arranged to draw into the venturi a predetermined flow of primary air. The primary
air mixes in the venturi with the fuel gas to form a fuel-air pre-mixture having a
predetermined fuel-air ratio and flows out of the venturi into a body or discharge
chamber of the blade element.
[0003] A typical blade element is formed from opposing halves of sheet metal stampings/pressings,
which define both the venturi tube and its associated distribution chamber. The distribution
chamber defines a discharge path for discharge of the fuel-air mixture and a burner
head/diffuser is used to cap the discharge path. The diffuser has a burner membrane
in which a series of slots or other passages are formed and through which the fuel-air
mixture is discharged and conducted towards a combustion zone on the flame side of
the burner membrane. The diffuser is typically formed by an operation such as folding,
rolling, pressing or stamping so that the burner membrane runs along the length of
the diffuser and is supported by sides of the diffuser which are adapted to be fitted
over and along an associated burner blade. The diffuser may be held in position by
for example clamping, clinching or crimping. Once the fuel-air mixture has been discharged
through the membrane passages, it is ignited by a pilot light or other ignition means.
[0004] To provide fuel, it is known to pipe a supply of gas into a chamber of a manifold
from a pressurized supply and the chamber may comprise a plenum chamber. Such manifolds
are often used to distribute the fuel supply between a plurality of fuel injectors,
each of which are mounted on the manifold and are adapted to supply a predetermined
stream of fuel gas out of the manifold in a predetermined direction. Each injector
injects this outflow of fuel into an inlet opening of a premix chamber/venturi tube
of an associated blade element, the fuel gas drawing in with it a supply of primary
air. The manifold may comprise, for example, a longitudinally extending cast, drawn
or rolled tube/duct having an axial line of holes in each of which is fitted an injector.
The spacing and alignment of the holes substantially matches the disposition of inlet
openings of associated burner blades.
[0005] These gas fuel injectors may be assembled from several parts about a threaded nozzle,
the nozzle being formed from for example copper or yellow brass and through which
is defined a narrow hole/injection channel for conducting gas out of the manifold
in a predetermined direction. The nozzle may include an integral hexagonal head or
separate flange nut and other components may include backing and/or locking flange
nuts with associated washers and seals. All of these features are used to mount the
nozzle on the manifold in a supposedly predetermined manner. One prior art proposal
of this general type can be found in FR2631105, in which a multi-blade premix gas
burner is disclosed.
[0006] With a large number of components making up each fuel injector assembly, the scope
for accumulative error in the tolerance stack and in assembly of this type of arrangement
is large and might result in inconsistent or irregular fuel supply between blades
or even between whole burners. In the case of a single element burner, these issues
may result in a wide spread between different burners. The result might be that fuel
gas is not always directed straight into the inlet opening and may be directed at
an angle, causing undesirable swirl and possibly uneven mixing resulting in lean and
rich portions in the fuel-air pre-mixture. In addition to angular inaccuracies, the
vertical and/or horizontal positioning of the injection channel with respect to the
centerline of the inlet opening should also be considered, as this may cause similar
errors to angular inaccuracy. Furthermore, as the fuel injectors may be independently
assembled, there is also the possibility that different types, forms or ratings of
injectors may be mixed on the same manifold with unequal injection between blade inlets
and consequent unequal output between blades. It is also often the case that a large
component count does not meet modern aspirations in designing for manufacture and
results in component and production costs which may rise with the number of parts
used and contribute to a potentially uncompetitive product.
[0007] It is clearly desirable to seek arrangements that reduce parts count, manufacturing
complexity, cost and the possibility of consequent accumulative error through tolerance
stacking and inconsistencies in assembly.
SUMMARY OF THE INVENTION
[0008] It is an object of the present invention to provide an improved burner arrangement.
It is a further object of the present invention to provide an improved fuel injection
assembly for a burner, which fuel injection assembly offers a reduced component count
and/or easier manufacturing and assembly techniques than some current arrangements
and consequently benefits from reduced manufacturing costs. It is also an object of
the present invention to provide improved methods and materials used to manufacture
such fuel injection and burner arrangements.
[0009] Accordingly, the present invention provides a fuel injection assembly for a gas burner,
said assembly comprising a manifold which is adapted to receive a gaseous fuel from
a fuel supply, characterized in that said manifold comprises a channel member and
an injector rail, said channel member defining a channel opening and said injector
rail covering said channel opening such that said channel member and said injector
rail define a chamber for receipt of said gaseous fuel, said injector rail being provided
with at least one injector comprising an injector outlet, said injector outlet perforating
said injector rail and said injector being adapted to supply said gaseous fuel outwardly
from said manifold in a predetermined direction. The injector rail is preferably sealingly
connected to the channel opening. The sealing connection may be provided by a seal
placed between the injector rail and the channel. The seal may be compressed by a
connection between the rail and the channel.
[0010] The outlet forms an aperture through which the gas is directed. The aperture may
be defined by a surrounding wall which is integral which the rail. For example, said
injector may comprise a raised profile that is formed integrally with said injector
rail and rises therefrom. Said injector may comprise an injector nozzle located in
the injector outlet. Said injector outlet may define a hollow portion accommodating
partially or fully said injector nozzle. The nozzle may be a forced fit into the injector
outlet.
[0011] Said injector rail may comprise a section of malleable sheet or plate material and
the or each said injector may be formed integrally therewith by deformation of said
material. Said injector rail may comprise a section of extruded, cast or molded material
and the or each said injector may be formed integrally therewith by at least one of
extrusion, casting, molding or machining. Said injector rail may comprise at least
one of aluminum or an alloy thereof, copper or an alloy thereof, a brass such as in
particular a yellow brass, or a stainless steel.
[0012] Said channel member may comprise a malleable sheet or plate material and said channel
member may be formed by deformation of said material. Said channel member may comprise
an extrusion, casting or molding formed, for example, from aluminum or an alloy thereof.
Said channel member may include abutment members adapted to locate said injector rail
across said channel opening, said abutment members comprising for example corrugations
or flanges disposed on opposing and preferably inwardly facing sides of said channel
member.
[0013] Said injector rail and said channel member may be held together by a mechanical connection,
for example by at least one of an adhesive bond, solder, braze, weld, fold, crimp,
clinch, rolled joint, rivet, clamp, screw or bolt. It is preferred if the injector
rail is sealingly connected to the channel member.
[0014] Said assembly may include a connection means adapted for making a connection between
said fuel injection assembly and a burner, a said connection preferably including
alignment in a predetermined relationship of the or each said fuel injector with an
associated inlet port of said burner.
[0015] The present invention also provides a gas burner including a fuel injection assembly
according to the invention, said burner comprising a burner element associated with
the or each said fuel injector, the or each said burner element defining an inlet
which is substantially aligned with its associated said fuel injector.
[0016] Said predetermined direction for the gas may be orientated substantially along a
centerline of said inlet and the or each said burner element may be adapted to draw
in a supply of primary air with said gaseous fuel so as to form in said burner element
a premix of gaseous fuel and primary air, the or each said inlet comprising for example
a venturi.
[0017] Said burner may comprise a multi-blade premix gas burner including an array of spaced
apart and substantially parallel blade elements, each said burner element comprising
a burner blade. Said burner may include a connection means adapted for connection
of said fuel injection assembly and the or each said burner element in a predetermined
relationship.
[0018] The present invention also provides a method of producing a fuel injection assembly
for a gas burner, the method including:
a) providing a channel member which defines a channel opening;
b) providing an injector rail which includes one or more fuel injectors, the or each
said injector including an injector outlet which perforates said injector rail; and
c) attaching said injector rail across said channel opening such that said channel
member and said injector rail form at least part of a manifold that defines a chamber
for receipt and distribution of a gaseous fuel.
[0019] The present invention also provides a method of producing a gas burner, preferably
a multi-blade gas burner, the method including:
a) providing one or more burner elements, the or each said burner element defining
an inlet opening adapted to receive injection of a gaseous fuel;
b) providing a fuel injection assembly according to the invention; and
c) aligning the or each fuel injector of said fuel injection assembly with a said
inlet opening, preferably substantially along a centerline thereof, in such a manner
as to draw a supply of primary air into said inlet opening along with injected said
gaseous fuel.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020]
Figure 1 is a schematic diagram in cross section through part of a burner including
a fuel injection assembly according to an embodiment of the present invention;
Figures 2a and 2b are sections through part of the fuel injection assembly of the
burner depicted in Figure 1 along the line A-A' prior to and after assembly respectively;
Figures 3a and 3b are sections through part of the fuel injection assembly of the
burner depicted in Figure 1 along the line B-B' prior to and after assembly respectively;
Figure 4 is a plan view over a fuel injector of the fuel injection assembly of the
burner depicted in Figure 1 along the line C-C';
Figure 5 is a schematic perspective view of an injector rail of the fuel injection
assembly depicted in Figure 1; and
Figure 6a and Figure 6b are sections through variations of a fuel injector rail of
Figures 1 to 5.
DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT
[0021] The present invention will now be described with reference to certain embodiments
and with reference to the above mentioned drawings. Such description is by way of
example only and the invention is not limited thereto.
[0022] Referring to the drawings, a multi-blade gas burner 10 comprises at least one 12a
and (as drawn) preferably a plurality of burner elements in the form of burner blades
(12a, 12b to 12n). The or each blade 12a-n defines an inlet opening 14 across the
mouth of a venturi tube 16, through which in use a fuel 18 is introduced from a fuel
injection assembly 20.
[0023] The fuel injection assembly 20 includes a fuel distribution manifold 22 that is assembled
from two major structural components, a channel member 24 and an injector rail 26.
The manifold 22 is closed at its opposing ends, either by integral end walls or by
plugs. In one embodiment such plugs are inserted and riveted, using the base material
of the manifold 22. At one end, the manifold 22 is provided with a gas supply means
in the form of a metered gas inlet G, that is adapted to supply into the manifold
22 a pressurized supply of a gaseous fuel and a suitable such fuel may comprise a
natural gas such as methane, butane or propane. The gas inlet G may instead be positioned
on another side of the manifold 22, as convenient for manufacture or gas supply.
[0024] The channel member 24 defines a longitudinally extending chamber 240 which is of
a length adapted to the number of blades 12a-n the manifold 22 must service and has
a longitudinal channel opening extending along it. The cross-sectional shape of the
channel member 24 and its internal volume may reflect the manufacturing technique
used to make it and/or may be adapted to achieve one or more particular functional
features, such as accumulation of fuel 18 or a predetermined geometry of fuel distribution.
The particular cross-sectional area shown in the Figures 2a to 3b by way of example
for the channel member 24 is a substantially "U" shaped channel open along one side,
although it will be appreciated that this may take many other forms, e.g. a circular
section. The channel member 24 includes integral abutment members, which are in the
form of flanges 30 and are adapted to support the injector rail 26 across the open
side of the channel member 24.
[0025] In one version, the channel member 24 is made from a malleable sheet or plate material
and its shape may be imparted by deformation of the material, e.g. using one or more
techniques such as folding, rolling, stamping, pressing or punching. Suitable materials
for the channel member 24 may include aluminum or some of its alloys. The properties
of a stainless steel, copper or an alloy thereof such as brass (and in particular
a yellow brass) may also be found useful, e.g. in a plastic deformation technique
such as molding or thermoforming.
[0026] In the particular case illustrated in Figures 2a to 3b, each flange 30 is formed
integrally as a corrugation or fold, each opposing a counterpart 30 and disposed towards
and/or along the region of an outer limit of each side of the channel member 24. Beyond
each flange 30 in this version, there remain strips of the sides of the channel member
24 that will be referred to here for convenience as retention strips 32. During assembly
of the manifold 22, the retention strips 32 are bent over the injector rail 26 to
hold it in position sealed against the flanges 30, being bent over in the direction
of the arrows in Figures 2a and 3a so as to form the assembly illustrated in Figures
2b and 3b respectively. Similar retention/joining techniques that might prove useful
include crimping, clinching, rolling or folding. In this version, it is preferable
for the abutment members 30 to face inwards on opposing sides of the channel member
24, such that the injector rail 26 substantially closes off the chamber 240 along
the open side of the channel member 24. The injector rail 26 is preferably stiffer
than the channel member 24 and the outer edges of the injector rail 26 provide purchase
for the retention operation without the rail 26 collapsing or creasing. Once assembled,
the injector rail 26 and channel member 24 may then form a substantially box type
or log profile for the manifold 22, defining the chamber 240 which may comprise a
plenum chamber.
[0027] In a second version, the channel member 24 may be formed using a technique such as
extrusion, molding or casting, e.g. die-casting. In this case the flanges 30 may be
formed integrally with the sides of the channel member 24 as part of the casting itself.
A rigid channel member 24 may not lend itself to bending over strips of its material
and the above described arrangement of holding an injector rail 26 in place using
bent over retaining strips 32 may therefore prove unworkable for some channel member
materials. The injector rail 26 could instead be held sealed in place using a variety
of other mechanical connections, many of which could also be used or adapted for channel
members 24 other than cast versions and used in variations to the first version. Useful
techniques may include, for example, an adhesive bond, soldering, brazing or welding.
In the alternative, or in addition, one or more fixings may be used such as rivets,
clamps, screws or bolts.
[0028] Optionally, an additional seal 34 such as a gasket or a sealing compound/paste may
be used to aid sealing between the channel member 24 and the injector rail 26. This
may be found useful in particular in cases where a compressive force is used to hold
the injector rail 26 in place. Such sealing 34 may in addition or in the alternative
include an adhesive agent. The seal 34 may be disposed between the injector rail 26
and the abutment members, in particular in the event that the abutment members comprise
flanges 30 that are continuous along the length of the channel member 24. A rubber
seal or cork-rubber seal may be used, although special attention needs to be given
to temperature resistance of the chosen material because maximum temperature can rise
to 200 °C.
[0029] Turning now to the injector rail 26, in each version this component supports one
or more integrated fuel injectors 28 disposed along the injector rail 28, one fuel
injector 28 each for the or each burner blade 12a-n to be supplied. In a first version
the injector rail 26 is made from a strip of malleable sheet or plate material and
in each case its length reflects the number of fuel injectors 28 to be supported and
the associated length of channel opening along the channel member 24. The or each
fuel injector 28 is formed on the injector rail 26 and comprises a fuel injector gas
outlet. The gas outlet may be formed as an at least partially hollow raised profile
by deformation of the strip material, using for example one or more techniques such
as stamping, pressing or punching. Suitable materials for the injector rail 26 may
include aluminum or some of its alloys for either casting or in a plastic deformation
technique. The properties of a stainless steel, copper or an alloy thereof such as
brass (and in particular a yellow brass) may also be found useful, e.g. in a plastic
deformation technique such as molding or thermoforming.
[0030] Each injector 28 includes an injector opening or outlet in the form of an injection
passage 36 adapted to allow in use a supply of gaseous fuel 18 to pass outwardly from
the manifold 22 and away from the injector rail 26 in a predetermined direction. The
fuel exits under its own pressure and, when directed by the injector 28 into an inlet/venturi
16 of an associated burner element, can be considered to be injected into that element.
The injection passage 36 may be defined directly in the tip of the or each injector
28, by for example punching or machining, either before or after the injector profile
is formed. The size of the injection passage 36 and the geometry of the injector 28
dictate the rate and orientation at which fuel 18 is conducted outwardly, which in
use will be towards its associated venturi 16. In the specific example illustrated
in Figures 1, 3a and 3b, the injector profile is similar in cross-section to a bell.
An alternative profile may use a substantially conical or frustro-conical raised profile
so as to produce a more pointed fuel injector 28. It is preferable in each embodiment
not to mix different shapes of injector 28 on the same injector rail 28, so as to
maintain equal flow of fuel gas and/or primary air into the or each venturi 16.
[0031] Optionally, the raised profile and/or injector opening of the or each fuel injector
28 may further be adapted to accommodate an injector nozzle located therein, e.g.
in the form of an insert 28a which defines an injection passage 36a and is at least
partially substantially complementary in external shape to that of at least a portion
of the inside of the raised profile of the injector 28. To this end, the raised profile
may serve to hold the nozzle 28a located in its opening, and the nozzle may be fitted
from the inside and may protrude from the tip of the hollow profile. The nozzle may
be a forced fit into the injector outlet. The injection passage 36a of the injection
nozzle 28a may be considered as an injector opening or gas outlet that complements
or replaces the use of the injector opening in an embodiment comprising a simple hollow
profile. At least some and possibly all directionality, swirl or other forms of fuel
distribution may then be imparted by the profile of the injection passage 36a defined
through the nozzle. Such an insert 28a may be pressed in and may be made of for example
copper or yellow brass. It may prove preferable to chamfer, countersink or otherwise
profile the injection passage 36a at its inner and/or outer end, e.g. to aid gas flow
or to achieve a particular fuel injection pattern. The size of the injector openings
36, 36a can be varied between injector rails 26 to provide different volumetric flow
rates of fuel gas between different manifolds 22, so as to enable the production of
differently rated burners using several common parts. In common with all other embodiments
the outer shape of the injector 28, e.g. bell or cone, may be used to affect, direct
or tune the flow of primary air 38 into the or each venturi 16.
[0032] In a second version, an injector rail 260 may be formed as a casting, molding or
extrusion, for example from aluminum or one of its alloys. In this case, the gas outlet
is formed integrally with the injector rail. For example, a raised profile of the
or each fuel injector 280a, 280b is formed integrally with the injector rail 260 by
at least one of casting, molding, extrusion and machining and no separate nozzle need
be contemplated. Such an arrangement is disclosed with particular reference for the
moment to Figures 6a and 6b, in which the or each injector outlet may be completed
by machining. For instance an opening may be formed at least in part by machining,
e.g. by facing off an injector profile at its tip and cutting an injection passage
360 through to create the or each injector opening. The injectors of Figures 6a and
6b differ only in their outer profile, comprising a bell shape 280a and a frustro-conical
shape 280b respectively. In any case and in similar fashion to the optional inserts
of the hollow fuel injector 28 versions, it may prove preferable to chamfer, countersink
or otherwise profile the injection passage 360 of any cast, molded or extruded version
at its inner and/or outer end, e.g. to aid laminar flow or to achieve a particular
fuel injection gas flow pattern. This configuration may also be achievable without
machining by using a technique such as die-casting or injection molding. In similar
fashion to the hollow fuel injector versions 28, with or without optional inserts
28a, it will be appreciated that the outer profiles of the bell/cone shaped cast-on
fuel injectors 280a, 280b can be used to achieve differing effects on the flow of
primary air 38 into one or more associated venturis 16.
[0033] In use, fuel gas 18 exits the manifold 22 through the or each injector 28, 280a,
280b, i.e. through either an injector opening in the form of an injection channel
36, 360a, 360b defined in the raised profile/injector 28, 280a, 280b or through an
injection channel 36a in an inserted nozzle 28a as the case may be. The fuel gas 18
exits the manifold 22 under its own pressure and is directed by the injector 28, 280a,
280b towards the venturis 16 of associated burner blades 12a-n. The fuel gas 18 can
thus be considered to be injected into the entrance of the venturi tubes 16, substantially
along a centerline C/L, and thereby draws in primary air 38 from the atmosphere. The
fuel 18 and primary air 38 are mixed to a predetermined ratio during their passage
through the venturi tube 16 and a typical fuel-air mixture 18, 38 has 60 to 80% primary
air. The fuel-air mixture 18, 38 passes further into the blade 12a-n and is accumulated
in a discharge chamber from which it exits under its own pressure through a burner
membrane/diffuser (none illustrated) capping the blade elements (12a, 12b to 12n)
in question. After discharge from the or each diffuser, secondary air and ignition
are applied to the fuel-air pre-mixture 18, 38.
[0034] The fuel injection assembly 20 and the burner elements 12a-n include connection means
which are adapted to align and stake in place the manifold 22 such that each fuel
injector's out flow of fuel gas is injected into its associated venturi 16 in a predetermined
direction. This direction is preferably substantially along a centerline C/L of the
venturi opening 14, such that the draft of primary air 38 is drawn into the venturi
16 distributed evenly around the injected fuel 18 and homogenous mixing is thereby
better facilitated. The alignment and staking is preferably also controlled in terms
of vertical and horizontal positioning of fuel injectors 28, 280a, 280b for similar
reasoning to their angular alignment. A good alignment between the manifold 22 and
the or each blade 12a-n provides for maximum intake of primary air. This in turn means
that the amount of gas used can be maximized, such that the capacity per burner bar/blade
is as high as possible in combination with good results for combustion efficiency.
The way this is implemented according to the alignment and staking of the present
invention leads to a reduction in the number of parts used compared with some known
arrangements and to an associated decrease in the overall tolerances of the assembly.
Furthermore, the staking of the blades to the manifold results in a direct link between
these two critical components without using several other parts for the connection
as is done in some known multi-blade burners.
[0035] It will be appreciated that the manner in which a fuel-air mixture 18, 38 is discharged
or otherwise used after introduction into a venturi 16 or discharge chamber 24 is
not an essential feature of the present invention and that it may therefore be discharged
and used in ways other than the one specifically described.
[0036] According to the present invention, the component count, manufacturing complexity,
time and costs of providing a burner 10 are reduced, which is achieved by integrating
the or all the injectors 28; 280a; 280b into an injector rail 26; 260 of the manifold
22. If multiple injectors 28; 280a; 280b are used, the present invention can ensure
that they are all of substantially identical dimensions and can guarantee that all
injectors 28; 280a; 280b are of the same type, form and rating. The angular, vertical
and horizontal alignment of the manifold 22 and therefore the injectors 28; 280a;
280b with the venturis 16 may become a function of the manufacturing tooling and less
so of the assembly operation. This lends itself to a reduction in the tolerance stack
and variability during assembly of the burner 10, with consequent improvements in
directionality and distribution of injected fuel, better pre-mixing with primary air
38 and ultimately to improved combustion efficiency.
[0037] While the present invention has been particularly shown and described with respect
to a preferred embodiment, it will be understood by those skilled in the art that
changes in form and detail may be made without departing from the scope and spirit
of the invention. For example, the present invention has been described with reference
to a specific example comprising a multi-blade burner, although it will be appreciated
that a single blade version is equally possible by simple modification to the multi-blade
embodiment. In this event, only a single blade or other configuration of burner element
is provided and only one fuel injector is formed on the injector rail.
1. A fuel injection assembly for a gas burner, said assembly comprising a manifold which
is adapted to receive a gaseous fuel from a fuel supply, characterized in that said manifold comprises a channel member and an injector rail, said channel member
defining a channel opening and said injector rail covering said channel opening such
that said channel member and said injector rail define a chamber for receipt of said
gaseous fuel, said injector rail being provided with at least one injector comprising
an injector outlet, said injector outlet perforating said injector rail and said injector
being adapted to supply said gaseous fuel outwardly from said manifold in a predetermined
direction.
2. An assembly according to claim 1, wherein said injector outlet comprises a raised
profile that is formed integrally with said injector rail and rises therefrom.
3. An assembly according claim 1 or claim 2, wherein said injector comprises an injector
nozzle located in said injector outlet.
4. An assembly according to claim 3, wherein said injector defines a hollow portion accommodating
partially or fully said injector nozzle.
5. An assembly according to any preceding claim, wherein said injector rail comprises
a section of malleable sheet or plate material and the or each said injector is formed
integrally therewith by deformation of said material.
6. An assembly according to any one of claims 1 to 4, wherein said injector rail comprises
a section of extruded, cast or molded material and the or each said injector is formed
integrally therewith by at least one of extrusion, casting, molding or machining.
7. An assembly according to any preceding claim, wherein said injector rail comprises
at least one of aluminum or an alloy thereof, copper or an alloy thereof, a brass
such as in particular a yellow brass or a stainless steel.
8. An assembly according to any preceding claim, wherein said channel member comprises
a malleable sheet or plate material and said channel member is formed by deformation
of said material.
9. An assembly according to any one of claims 1 to 7, wherein said channel member comprises
an extrusion, casting or molding formed, for example, from aluminum or an alloy thereof.
10. An assembly according to any preceding claim, said channel member including abutment
members adapted to locate said injector rail across said channel opening, said abutment
members comprising for example corrugations or flanges disposed on opposing and preferably
inwardly facing sides of said channel member.
11. An assembly according to any preceding claim, wherein said injector rail and said
channel member are held together by a mechanical connection, for example by at least
one of an adhesive bond, solder, braze, weld, fold, crimp, clinch, rolled joint, rivet,
clamp, screw or bolt.
12. An assembly according to any preceding claim, wherein said assembly includes connection
means adapted for making a connection between said fuel injection assembly and a burner,
a said connection preferably including alignment in a predetermined relationship of
the or each said fuel injector with an associated inlet port of said burner.
13. A gas burner including a fuel injection assembly according to any preceding claim,
said burner comprising a burner element associated with the or each said fuel injector,
the or each said burner element defining an inlet which is substantially aligned with
its associated said fuel injector.
14. A gas burner according to claim 13, wherein said predetermined direction is orientated
substantially along a centerline of said inlet and wherein the or each said burner
element is adapted to draw in a supply of primary air with said gaseous fuel so as
to form in said burner element a premix of gaseous fuel and primary air, the or each
said inlet comprising for example a venturi.
15. A gas burner according to claim 13 or claim 14, wherein said burner comprises a multi-blade
premix gas burner including an array of spaced apart and substantially parallel blade
elements, each said burner element comprising a burner blade.
16. A gas burner according to any one of claims 13 to 15, wherein said burner includes
connection means adapted for connection of said fuel injection assembly and the or
each said burner element in a predetermined relationship.
17. A method of producing a fuel injection assembly for a gas burner, the method including:
a) providing a channel member which defines a channel opening;
b) providing an injector rail which includes one or more fuel injectors, the or each
said injector including an injector outlet which perforates said injector rail; and
c) attaching said injector rail across said channel opening such that said channel
member and said injector rail form at least part of a manifold which defines a chamber
for receipt and distribution of a gaseous fuel.
18. A method of producing a gas burner, preferably a multi-blade gas burner, the method
including:
a) providing one or more burner elements, the or each said burner element defining
an inlet opening adapted to receive injection of a gaseous fuel;
b) providing a fuel injection assembly according to any one of claims 1 to 12; and
c) aligning the or each fuel injector of said fuel injection assembly with a said
inlet opening, preferably substantially along a centerline thereof, in such a manner
as to draw a supply of primary air into said inlet opening along with injected said
gaseous fuel.