EP1355110A1

EP1355110A1 - Burner arrangements

Info

Publication number: EP1355110A1
Application number: EP02076529A
Authority: EP
Inventors: designation of the inventor has not yet been filed The
Original assignee: Furigas Assen BV
Current assignee: Furigas Assen BV
Priority date: 2002-04-18
Filing date: 2002-04-18
Publication date: 2003-10-22

Abstract

A fuel injection assembly for a gas burner is disclosed, the assembly comprising a manifold 22 which is adapted to receive a gaseous fuel from a fuel supply G. The manifold 22 comprises a channel member 24 and an injector rail 26, the channel member 24 defining a channel opening and the injector rail 26 covering that channel opening such that the channel member 24 and the injector rail 26 define a chamber 240 for receipt of the gaseous fuel. The injector rail 26 is provided with at least one injector 28 comprising an injector gas outlet, the or each injector gas outlet perforating the injector rail 26 and the injector 28 being adapted to supply the gaseous fuel outwardly from the manifold 22 in a predetermined direction. The gas outlet may be in the form of a raised section formed integrally in the injector rail.

Description

FIELD OF THE INVENTION

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

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.
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.
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.
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.
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.
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

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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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

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

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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.

Claims

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.
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.
An assembly according claim 1 or claim 2, wherein said injector comprises an injector nozzle located in said injector outlet.
An assembly according to claim 3, wherein said injector defines a hollow portion accommodating partially or fully said injector nozzle.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.