EP1802916A2

EP1802916A2 - Burner with diffuser resistant to high operating temperatures

Info

Publication number: EP1802916A2
Application number: EP05789535A
Authority: EP
Inventors: Giuseppe Fogliani; Massimo Gilioli; Massimo Dotti
Original assignee: Worgas Bruciatori SRL
Current assignee: Beckett Thermal Solutions SRL
Priority date: 2004-10-22
Filing date: 2005-10-10
Publication date: 2007-07-04
Anticipated expiration: 2025-10-10
Also published as: US20070298361A1; WO2006045426A2; ITMO20040277A1; EP1802916B1; WO2006045426A3; RU2006145638A; ATE543047T1

Abstract

A burner suppliable with a mixture of air and fuel, comprising a diffuser on which holes are made for the passage and subsequent combustion of said mixture, said diffuser being divided into a plurality of diffuser elements adjacent to one another, said diffuser elements are fixable to a support and distribution element provided with first coupling elements for coupling with said diffuser elements and with openings for distributing said mixture to said diffuser elements.

Description

Burner with diffuser resistrant to high operating temperatures.

The present invention relates to a burner with a diffuser resistant to high operating temperatures, in particular to a premix burner.

In the burners subject to high operating temperatures, such as for example the premix burners, the high thermal stresses can easily causes deformation and mechanical stresses on the diffuser of the burner, which may cause the diffuser to break. This drawback occurs with any form of diffuser of the burner, but has been shown to be particularly serious in burners with flat diffusers. In order to remedy the above drawback, it has been proposed to use special materials for making the diffuser of the burner, for example a metal mesh or a ceramic material. However, this results in a significant increase in the cost of the burner in the event of use of the metal mesh and significant fragility of the diffuser in the event of use of a. ceramic material. It has also been proposed to divide the diffuser of the burner to reduce mechanical- stresses arising from temperature variations during biαrner operation. Burners of this type are known from patent applications MO2003A000180 and MO2004A000031, in the name of the same applicant. In these patent applications bαrners are disclosed wherein the diffuser of the burner is divided into a plurality of diffuser elements that are adjacent to one another, that are free to expand in at least one direction.

The burners disclosed in the aforementioned patent applications satisfactorily sol~ve the problem of reducing the mechanical stresses gene.rated by the temperature variations to which the difffuser is subjected during operation of the burner and by temperature differences between the various zones of "the diffuser; nevertheless, said burners are complex to make and are relatively expensive. The present invention aims at providing burners of the aforementioned type with divided diffusers that are simpler and cheaper to make.

According to the present invention a burner is provi<ded that is suppliable with a mixture of air and fuel, comparising a burner body provided with a diffuser on which openings are made for the passage and subsequent combustion of said mixture, said diffuser being divided into a plurality of diffuser elements that are adjacent to one -a.noth.er, characterised in that said diffuser elements are fi>ced to a support and distribution element provided with first mechanical coupling means for coupling with said diffuser elements and with openings for distributing said mi-xture to said diffuser elements.

Owing to the invention, the construction and assembly of the burner is significantly simplified, inasmuch as a same element acts as a support for the diffuser elements .and as a distributor of the mixture to the diffuser elements and it is therefore no longer necessary to provide a dist xibuting element for each diffuser element. Furthermore, filing the diffuser elements to said support and distribution element is very simple and rapid to achieve, thus .reducing considerably burner assembly time.

Further advantages and features of the invention will be shown by the disclosure that follows that is given merely by way of non-limitative example with reference to the .attached drawings, in which:

Figure 1 is a view from above of a burner according to the invention, with a substantially flat diffuser;

Figure 2 is a view from above of a support element of the diffuser of the burner in Figure 1, that also acts as a distributing element of the mixture with which the biirner is supplied;

Figure 3 is a view from above of a diffuser element of a burner according to the invention; Figures 4 and 5 a:tre, respectively, a side view and a frontal view of the diffuser element of Figure 3;

Figure 6 is a perspective view of the diffuser element of

Figure 3 ;

Figure 7 is a perspective view of a burner according to the invention, with a prismatic diffuser;

Figure 8 is an elevation view of the burner in Figure 7 ;

Figure 9 is a plan view of the burner in Figure 7;

Figure 10, is a perspective view of a further emboditnexit of a support and d±stribution element for a burner diffuser according to the invention;

Figure 11 is a perspective view of a burner diffuser made with the support and distribution element of Figure 10 ;

Figure 12 is a. perspective view of a still fuirther embodiment of a support and distribution element for a burner diffuser according to the invention;

Figure 13 is SL view from above of the support and distribution element in Figure 12;

Figure 14 is a perspective view of a burner diffuser made with the support and distribution element in Figure 12 ;

Figure 15 is a view from above of the burner diffuser in

Figure 14;

Figure 16 is a perspective view of another embodiment of a support and distribution element for a burner diffuser according to the invention;

Figure 17 is a perspective view of a burner diffuser made with the support and distribution element of Figure 16;

Figure 18 is a perspective view of a support frame for a burner diffuser according to the invention;

Figures 19-23 illustrate details of the frame in Figure 18.

Figure 24 is a perspective view of a burner diffuser f itted in the frame of Figure 18;

Figure 25 is a pa.xtial view from above of Figure 24;

Figure 26 is the section XXVI-XXVI of Figure 25;

Figure 27 is the section XXVII-XXVII of Figure 25;

Figure 28 is an enlarged detail of Figure 25; Figure 29 is the section XXIX-XXIX of Figure 25;

Figure 30 is a view from above of a further embodiment of burner diffuser according to the invention;

Figure 31 is a perspective view of the diffuser in Figure

30;

Figure 32 is a side view of the diffuser in Figure 30;

Figure 33 is an enlarged detail of Figure 32;

Figure 34 is a view from above of a further embodiment of a support and distribution element for a burner di±fuser according to the invention;

Figure 35 is a perspective view of the support and distribution element in Figure 34;

Figure 36 is the section XXXVI-XXXVI in Figure 34;

Figure 37 is the section XXXVII-XXXVII in Figure 34;

Figure 38 is a perspective view of a burner diffuserr made with the support and distribution element in Figure 34;

Figure 39 is a view from above of a burner diffuser according to the invention, which illustrates an alternative arrangement of the diffuser elements on a support and distribution element;

Figure 40 is a view like the one in Figure 39, that illustrates a further arrangement of the diffuser elements on a support and distribution element;

Figure 41 is a view like those in Figures 39 and 40, which illustrates a still further arrangement of the di±fuser elements on a support and distribution element

Figure 42 is a perspective view of a further embodiment: of a support and distribution element according to the invention;

Fig. 43 is a view according to arrow F of the suppo-trt and distribution element in Figure 42;

Figure 44 is a perspective view of a further embodiment of a support and distribution element according to the invention;

Figure 45 is a view according to arrow Fl of the suppoxt and distribution element in Figure 44;

Figure 46 is a perspective view of a further embodiment of a support and distribution element according to the invention, schematising the coupling to a wall of a heat exchanger, or of a combustion chamber;

Figure 47 is a perspective view of the support and distribution element in Figure 35, schematising tlie coupling to a wall of a heat exchanger, or of a combustion chamber. Figure 1 illustrates a first embodiment of a burner according to the invention wherein the diffuser 1 consists of a plurality of diffuser elements 2, shown irα detail in Figures 3 to 6, each of which has a substantially open box shape, with an upper face 3 intended to face the outside of the burner, two front faces 4, substantially perpendicular to the smaller sides of the upper face 3 and two side faces 5, 6, substantially perpendicular to the larger sides of the upper face 3. On the upper face 3 openings 7, 8, 9 are made for the exit of the mixture of air and fuel supplied to the burner. Said openings comprise rows of slits 7, for example two rows parallel to one another between which 3. plurality of holes 8 is arranged. At regular intervals along the rows of slits 7 and holes 8 further slits 9 can be arranged that extend over the entire width of said upper face 18. These further slits 9, in addition to acting as further openings for the passage of said mixture, enable said upper face 3 to absorb heat expansion without being subject to excessive mechanical stresses generated by said expansion. From each of the side faces 5, 6, appendages 10 protrucLe that are tilted towards the corresponding appendages 10 of the opposite side face, the function of which will b>e explained below.

The diffuser elements 2 are fitted next to one another on a support and distribution element 11, that may ha~ve the form of a flat quadrangular plate, as shown in Figures 1 and 2, but may also have a polygonal, circular oval shape and have a convex surface. In the plate 11 slits 12 are made that are arranged in rows that are substantially paral IeI to one another and are intended to be coupled with the appendages 10 of the diffuser elements 2 to fix the elements in position. The plate 11 is furthermore provided with groups of rows of holes 13, each group being arranged between two rows of slits 12, in such a way as to be level with a diffuser element 2 when the diffuser elements 2 are fitted to the plate 11. The groups of rows of holes 13 distribute the mixture of air and fuel delivered to the burner to the openings 7, 8, 9 of each diffuser element 2, guaranteeing a distribution of the flow of mixture to the aforementioned openings. The rows of slits 12 and the rows of holes 13 can be arranged parallel to a pair of opposite sides of the plate 11 or tilted in relation to the sides of the plate 11. The plate 11 performs both the function of support to the diffuser elements 2 and the function of distributor of the flow of mixture, which makes the burner structure more compact and makes assembly thereof very simple, it no longer being necessary to provide a separate d±stributor element for each diffuser element.

The plate 11, with the diffuser elements 2 that are fixed to it, constituting the diffuser 1 of the burner, can be fixed to a support frame, with a shape corresponding to the shape of the plate 11, which will be disclosed below. The diffuser elements 2 can be made of metal, ceramic material or of any other material resistant to the operating temperatures of the burner. The upper face 3 of the diffuser elements 2, rather than being provided with the openings 7, 8, 9, can be made of porous material with pore dimensions sufficient to ensure the passage of the mixture of air and fuel without excessive load losses.

Figures 7, 8 and 9 show a second embodiment of a burner according to the invention, in which the diffuser elements 2 are fixed to a support and distribution element 14 with a prismatic shape, which similarly to the plate 11 disclosed previously, also performs the function of distributor of the mixture of air and fuel delivered to the burner. Each face of the support and distribution element 14 is provided with two parallel rows of slits 12, intended to be coupled with the appendages of a diffuser element 2, to fix in position, the diffuser element 2 on the respective face of the support- element 14. Between the two rows of slits 13 parallel rows of holes 13 are arranged, to distribute the mixture to the openings made on the upper face of: the diffuser element 2. The burner is completed by an upper base and by a lower base that are not shown, in one of ΛΛ/hich a hole is made for^~ connecting a pipe supplying the mixture of air and fuel. The support and distribution element 14 may as an alternative have a cylindrical shape, in which the diffuser- elements 2 will preferably have a. slightly arched shape, in- such a way as to define as a whole a diffuser 1 with a_ substantially cylindrical shape.

In Figures 10 to 17 further versions of the support and distribution element in a burner according to the invention- are shown.

In Figures 10 and 11 a support and distribution element 14a_ is shown that has an upper face IL5 in which a plurality off rows of slits 12 is made for frLxing diffuser elements 2; between pairs of rows of adjacent slits 12 rows of holes 13 are made for distributing to the respective diffuser element 2 the mixture of air and fuel sujpplied to the burner. Both, the rows of slits 12 and the rows of holes 13 are arranged parallel to a pair of opposite sides of said upper face 15. The support and distribution element 14a furthermore has two L-shaped side faces 16, 17 connected to a pair of opposite; sides of the upper face 15, to constitute two support feet for the support and distribution element, suitable for^~ example for facilitating the coupling with a support frame; and/or adjusting the height of the diffuser of the burner- inside a combustion chamber, by varying for example the; height H of the side faces 16_r 17. In the support and distribution element 14a the rows of slits 12 and the rows of holes 13 are arranged perpendicular to the pair of sides to which the side faces 16 and 17 are connected. In Figures 12 to 14 another version of a support and distribution. element 14b according to the inventi_on is shown, which differs from the support and distribution element 14a inasmuch as the rows of slits 12 and the rows of holes 13 are parallel to the pair of sides to wh±ch the side faces 16 and 17 are connected. A burner according to the invention can be made with a support and distribution element 14a, 14b, with the respective diffuser elements 2 fixed thereto (Figures 11 and 14, 15) , all fitted in a support frame. Alternatively, a burner according to the invention can be made with a plurality of support and distribution elements 14a, 14b that are placed near one another and fitted in a containing frame, with the respective diffuser elements 2 fixed to each support and distribution element 14a, 14b. In Figures 16 and 17 a still further -version of a support and distribution element 14c is shown that differs from the support and distribution elements 14a and 14b by the fact that it has a box structure with an L- shaped side face 16, 17, 18, 19 connected to each of the sicles of the upper face 15; rows of slits 12 and holes 13 are arranged parallel to a pair of opposite sides of the upper face 15 of the support and distribution element 14c.

The rows of slits 12 and the rows of tioles 13 made in the upper face 15 of the support and distribution elements 14a, 14b, 14c can also be arranged tilted in relation to the sides of said upper face 15.

The upper face 15 of the support and cListribution elements 14a, 14b, 14c, similarly to the plate 11, may be flat and quadrangular in shape, but also have a polygonal, circular, oval shape and have a convex surface.

Figures 18 to 23 show an embodiment of a support and containing frame 21, with which the support and distribution elements 11, 14a, 14b, 14c can be coupled, with the relative diffuser elements 2, to assemble a burner according to the invention.

The frame 21 is a composable frame 21, consisting of two pairs of frame elements 22, 22a; 23, 23a that are assemblable together. Each element 22, 22a of the first pair of frame elements consists of a substantially rectangular flat element 24 a longitudinal edge 25 of which is folded back into a squashed "S" shape, wd_th an upper part 25a having a height a and a lower part 25b having a height b<a. Each element 23, 23a of the second pair of frame elements also consists of a flat element 26, a longitudinal edge 27 of which is folded back into a non-scjuashed "S" shape, with an upper part 27a having a height c and a lower part 27b having a height d.

The height c of the upper part 27a off the longitudinal edge 27 is less than the height a of the upper part 25a of the longitudinal edge 25 and the height cL of the lower part 27b of the longitudinal edge 27 is greater than the height b of the lower part 25b of the longitudinal edge 25. The frame elements 22, 22a, 23, 23a are coupled together to form a quadrangular frame, as shown in Figure 18, by inserting the upper part 27a of eachi edge 27 of the frame elements 23, 23a inside the upper panrt 25a of each edge 25 of a corresponding frame element 22, 22a, whereas the lower part 25b of each edge 25 of the frame elements 22, 22a is inserted into the lower part 27b of a corresponding frame element 23, 23a, all as shown in Figure 19. The fixing of the frame elements 22, 22a, 23, 23a can be achieved by crushing the elements after they have been coupled together and can be reinforced by welding.

Figures 24 to 29 illustrate the assembly of a support and distribution plate according to the invention, for example a plate of the type shown in Figures 1 and 2.

Two opposite edges 11a of the plate 11 are inserted inside the upper parts 25a of the longituclinal edges 25, folded into the shape of a squashed "S", of the elements 23, 23a, of the frame 21, as shown in Figures 26 and 27, whereas the other two opposite edges lib of the plate 11 are inserted in upper parts 27a of the longitudinal edges 27, folded into the shape of a non-squashed "S", of the elements 22, 22a of the frame 21, as shown in the Figure 29.

When the frame elements are fixed together by crushing-, the edges lla, lib of the plate 11 remain immobilised -Ln the respective squashed frame elements.

The plate 11 shown in Figures 24 to 29 has a slightly convex shape, but the same assembly can be achieved with si flat plate 11, or with a plate 14a, 14b, 14c.

Figures 30 to 33 show another diffuser version 28, associable with a frame 21 like the one shown in Figxire 18 and/or a support and distribution plate 11, 14a, 14b, H4c. The diffuser 28 consists of a plurality of diffuser el ements 29 arranged parallel to one another and connected together along the longer sides by elastic-hinge connecting meains 30. The elastic-hinge connecting means 30 are used to absorb the heat expansion generated by the temperature variaticons to which the diffuser 28 is subjected during burner oper-ation, thus enabling a reduction of the mechanical stresses <iue to said heat expansion and an increase in the working 1 άfe of the diffuser 28.

The diffuser 28 may be provided with appendages simi Har to the appendages 10 of the previously disclosed dLffuser elements 2 for coupling with a support and distrLbution plate 11, 14a, 14b, 14c.

Figures 34 to 37 show a further embodiment of a support and distribution element 31 according to the invention, which has an upper face 32 in which a plurality of rows of slits 12 is made for fixing diffuser elements 31; between pa_irs of rows of adjacent slits 12 rows of holes 13 are made for distribution to the respective diffuser element 2 of the mixture of air and fuel supplied to the burner. Bo^~th the rows of slits 12 and the rows of holes 13 are arrranged parallel to a pair of opposite sides of said upper fa.ce 15. The support and distribution element 31 furthermore b_as two side faces 33, 34 connected to a pair of opposite sides of the upper face 32. The side faces 33, 34 are each prrovided with a recess 35, 36 that extends over the entire length of the respective side face 33, 34. The recesses 35, 36 are suitable for facilitating, for example, coupling with a support frame and/or enabling easy coupling of the siαpport and distribution element 31 with a combustion chamber: or a heat exchanger.

The upper face 32 of the support and distribution element 31, similarly to the plate 11 and to the upper face 15 of the support and distribution elements 14a, 14b, 14c, may be flat and quadrangular in shape but may also have a polygonal, circular, oval shape and have a convex surface. The diffuser elements 2 can be assembled on the suppozrt and distribution elements 11, 14a, 14b, 14c, 31, not only in configurations shown in Figures 1, 11, 14, 15, 17, 38, but also according to any other configuration. Certain non- limitative examples of other configurations of the di±fuser elements 2 are illustrated in Figures 39, 40 and 41. Figure 39 illustrates a support and distribution element 11, on which three groups of diffuser elements 31 are arranged. The diffuser elements 2 of each group are parallel to one another whereas the diffuser elements 2 of the central group are oriented in a direction substantially perpendicular to the diffuser elements 2 of the other two groups. Figure 40 illustrates a support and distribution element 11 on which two groups of diffuser elements 2 are arranged, that are separated by a space S free of diffuser elements. Figure 41 illustrates a support and distribution element 11, on which four groups of diffuser elements 2 are arranged tilted in relation to the sides of the support and distribution element and delimiting a central space SH free of diffusex elements 2.

The slits 12 and the holes 13 on the support and distribution element must be arranged in such a way as to correspond to the arrangement of the diffuser elements 31. As already" said, any other arrangement configuration of the diffuser elements 2 is possible, by distributing in a corresponding" manner the slits 12 and the holes 13, the configuration of the diffuser elements 2 thus being adaptable, jΞor example, to the features of the heat exchanger of a boiler in which a burner according to the invention is installed.

Figures 42 and 43 illustrate a further version of a support and distribution element 37, that has an irjpper face 38 in which a plurality of rows of slits 12 is "made for fixing diffuser elements 2; between pairs of adjacent rows of slits 12 rows of rioles 13 are made for the distribution to the respective dd-ffuser element 2 of the mixture of air and fuel supplied to the burner. Both the rows of sILits 12, and the rows of holes 13 are arranged parallel to a ;pair of opposite sides of said upper face 15. The support and distribution element 37 furthermore has two side faces 39, 40 connected to a pair of opposite sides of the upper face 38. The side faces 39, 40 are each provided with a pluraJLity of recesses 41 arranged on each of said side faces 39, -40. The recesses 41 are suitable for facilitating, for example, coupling with a support frame and/or enabling easy coupling of the support and distribution element 31 with a combust_Lon chamber or a heat exchanger.

Figures 44 and 45 illustrate a further embodiment of a support and distribution element 42 according to the invention tlxat differs from the support aind distribution element 37 sliown in Figures 42 and 43 due to the fact that the side faces 39, 40 are provided with a plurality of protrusions 43, having the same function as the recesses 41 made on tlxe side faces 39, 40 of tine support and distribution element 37.

Figure 46 shows a further embodiment of a support and distribution element 44 according to the iiwention, similar to the support and distribution element 31 shown in Figure 35, from wh±ch it differs due to the fact that the side faces 33, 34= are each provided with respective protrusions 45, 46 that extend along the entire length of the respective side face 33, 34 and which perform the same function as the recesses 35, 36 made in the side faces of the s^~upport and distribution element 31.

Figure 46 furthermore schematically illustrates the fixing of the support and distribution element 44 to a heat exchanger or to a combustion chamber. Fixing occurs by coupling one of the protrusions 45, 46 with a corresponding recess 48 made in a respective wall 47 of the heat exchanger or of the combustion chamber.

Figure 47 illustrates the fixing of a support and distribution element 31 to a heat exchanger or to a combustion chamber. In this case, fixing occurs b^y means of coupling of one of the recesses 35, 36 with a corrresponding protriαsion 49 made in a corresponding wall 47 of the heat exchanger or of the combustion chamber.

Similarly, with reference to the versions of the support and distribution element illustrated in Figures 42 to 45, fixing of tlαe support and distribution element 37, 42 to a heat exchanger or to a combustion chamber occurs by coupling of the recesses 41 or protrusions 43 with corrresponding protriαsions or recesses made on the walls of the heat exchanger or of the combustion chamber.

In tlαe practical embodiment, the materials, the dimensions and the constructional details may be different from those indicated but be technically equivalent without thereby falling outside the legal scope of the present invention.

Claims

1. Burner suppliable with a mizxture of air and fuel., comprising a diffuser (1; Ia) on which holes are made for the passage and subsequent combusti_on of said mixture, said diffuser (1; Ia) being divided into a plurality of diffuser elements (2) that are adjacent to one another, characterised in that said diffuser elements (2) are fixable to a supporrt and distribution element (11; 14; 14a; 14b; 14c, 3JL) provided with first coupling means (12) for coupling with said diffuser (2) elements and opening (13) for distributing said mixture to said diffuser elements (2) .

2. Burner according to claim 1 , wherein said diffuser elements (2) are provided with second coupling means (1O) suitable for coupling with said first coupling means (12) .

3. Burner according to claim 1, or 2, wherein said first coupling means comprises further openings (12) made in said support and distribution element (11; 14; 14a; 14b; 14c; 31) .

4. Burner according to claim 3, wherein said second coupling means comprises appendages (10) of said diffuser elements (2) , suitable for coupling with said further openings (12) .

5. Burner according to claim 3, o_r 4, wherein said further openings (12) are arranged in rows, in pairs that aare parallel to one another.

6. Burner according to claim 5, wherein each pair of rows of said further openings (12) is pztrovided for coupling with the appendages (10) of a diffuser element (2) .

7. Burner according to any one o± claims 3 to 6, wherein said further openings (12) have the shape of slits.

rnsnogo „„*_«

8. Burner according to any one of claims 5 to 7, wherein said openings (13) for distributing said mixture are arranged between said pairs of rows of saicL further openings (12) .

9. Burner according to claim 8, wherein said openings (13) are arranged in rows parallel to the rows of said further openings (12) .

10. Burner according to any preceding claim, wherein said support and distribution element (11) has the shape of a quadrangular plate.

11. Burner according to any preceding claim, wherein said support and distribution element has the shape of a circular, polygonal or oval plate.

12. Burner according to claim 10, or 11, wherein said plate is flat.

13. Burner according to claim 10, or 11, wherein said plate is convex.

14. Burner according to claim 10, as appended to claim 9, wherein said rows of openings (13) and sai-d rows of further openings (12) are arranged parallel to a pair of opposite sides of said plate (11) .

15. Burner according to claim 10, as appended to claim 9, wherein said rows of openings (13) and sad_d rows of further openings (12) are arranged tilted in relation to the sides of said plate (11) .

16. Burner according to any one of claims 1 to 9, wherein said support and distribution element (14) has a tubular, cylindrical or prismatic shape.

17. Burner according to any one of claiLms 1 to 9, wherein said support and distribution element (14a; 14b) comprises an upper face (15) and two "L"-shaped s±de faces (16, 17), connected to a pair of opposite sides of the upper face (15), to act as two support feet.

18. Burner according to claim 17, whe-trein in said upper face (15) a plurality of rows of said further openings (12) is made, between pairs of rows of said further openings (12) rows of said openings (13) being made, both the rows of further openings (12) and the rows of openings (13) being arranged parallel to a pair of opposite sides of said upper face (15) .

19. Burner according to claim 17, wheitrein in said upper face (15) a plurality of rows of said further openings (12) is made, between pairs of rows of said further openings (12) rows of said openings (13) being made, both the rows of further openings (12) and the rows of openings (13) being arranged tilted in relation to the sides of said upper face (15) .

20. Burner according to any one of claims 1 to 9, wherein said support and distribution element (14c) comprises an upper face (15) and four "L"-shaped side faces (16, 17, 18, 19) , each of which is connected to a respective side of the upper face (15) .

21. Burner according to claim 20, whearein in said upper face (15) a plurality of rows of said fu.xth.er openings (12) is made, between pairs of rows of said fixrther openings (12) rows of said openings (13) being made, both the rows of further openings (12) and the rows of openings (13) being arranged parallel to a pair of sides opposite said upper face (15) .

22. Burner according to claim 20, wherein in said upper face (15) a plurality of rows of said fαirther openings (12) is made, between pairs of rows of said further openings (12) rows of said openings (13) being made, both the rows of fiarther openings (12) , and the rows of openings (13) being arranged tilted in relation to the sides of said upper face (15) .

23. Burner according to any one of claims 1 to 9, wherein said support and distribution element (31; 37; 42; 44) comprises an upper face (32; 38) and two side faces (33, 34; 39, 40) connected to a pair of opposite sides of the upper face (32; 38), each of said side faces (33, 34; 39, 40) being provided with connecting means (35, 36; 41; 43; 45, 46) suitable for allowing the connection of said support and distribution element (31; 37; 42; 44) to a heat exchanger or to a combustion chamber.

24. Burner according to claim 23, whe-trein said connecting means comprises at least a recess (35, 36; 41) obtained in each of said side faces (33, 34; 40) .

25. Burner according to claim 24, wherein said at least a recess (35, 36) substantially extends over the entire length of the respective side face (33, 34) .

26. Burner according to claim 23, whe-trein said connecting means comprises at least a protrusion (-43; 45, 46) obtained in each of said side faces (39; 33, 34) .

27. Burner according to claim 26, wherein said at least a protrusion (45, 46) substantially extends over the entire length of the respective side face (33, 34)

28. Burner according to any one of claims 23 to 27, wtierein in said upper face (32; 38) a plurality of rows of: said further openings (12) is made, between pairs of rows of said further openings (12) rows of said openings (13) being made, both the rows of further openings (12) and the rows of openings (13) being arranged parallel to a pair of opposite sides of said upper face (32; 38) .

29. Burner according to any one of claims 23 to 27, wlierein in said upper face (32; 38) a plurality of rows off said further openings (12) is made, between pairs of rows o± said further openings (12) rows of said openings (13) being made, both the rows of further openings (12) and the rows of openings (13) being arranged tilted in relation to the sides of said upper face (32; 38) .

30. Burner according to any preceding claim, furthermore comprising a composable support and containing frame (21) with which said support and distribution elements are couplable (11, 14a, 14b, 14c) .

31. Burner according to claim 30, wherein said frame (21) comprises a first pair of frame elements (22, 22a) and a second pair of frame elements (23, 23a) that are assemHolable together to constitute said frame (21) .

32. Burner according to claim 31, wherein each element: (22, 22a) of said first pair of frame elements consists of a. flat substantially rectangular element (24) a longitudinal edge of which (25) is folded into a squashed "S" shape.

33. Burner according to claim 32, wherein said longitudinal edge (25) comprises an upper part (25a) and a lower part

(25b) , said upper part (25a) having a height (a) greater than the height (b) of said lower part (25b) .

34. Burner according to any one of claims 31 to 33, wherein each element (23, 23a) of said second pair of frame elements consists of a flat substantially rectangular element (26) a longitudinal edge (27) of whicra is folded into an "S" shape.

35. Burner according to claim 34, wherein said longitudinal edge (27) comprises an upper part (27a) and a lower part

(27b) , said upper part (27a) heaving a height (c) lower than the height (a) of said upper part (25a) of the longitudinal edge (25) of each frame element (22, 22a) of said first pair of frame elements, said lower part (27b) having a height (d) greater than the height (b) of said lower part (25b) of each frame element (22, 22a) of said first pair of frame elements.

36. Support and containing frame (21) for a burner, characterised in that it comprises a first pair of frame elements (22, 22a) and a secorxd pair of frame elements (23, 23a) that are assemblable together to constitute said frame (21) .

37. Frame according to claim 36, wherein each element (22, 22a) of said first pair of frame elements consists of a substantially rectangular flat element (24) a longitudinal edge (25) of which is folded back into a squashed "S" shape.

38. Frame according to claim 37, wherein said longitudinal edge (25) comprises an upper part (25a) and a lower part

39. Frame according to any one of claims 36, to 38, wherein each element (23, 23a) of said secorxd pair of frame elements consists of a substantially rectangular flat element (24) a longitudinal edge (25) of which is folded back into a non- squashed "S" shape

40. Frame according to claim 39, wlherein said longitudinal edge (27) comprises an upper part (27a) and a lower part

(27b) , said upper part (27a) having a height (c) lower than the height (a) of said upper part ( 25a) of the longitudinal edge (25) of each frame element (22, 22a) of said first pair of frame elements, said lower part (27b) having a height (d) greater than the height (b) of said lower part (25b) of each frame element (22, 22a) of saicL first pair of frame elements.

41. Burner suppliable with a mixture of air and fuel, comprising a diffuser (28) on which, holes are made for the passage and the subsequent combustion of said mixture, said diffuser (1; Ia) being divided into a plurality of diffuser elements (29) adjacent to one another, characterised in that said diffuser elements (29) are connected together by elastic hinge connecting means (30) .

42. Burner according to claim 41, wherein said diffuser (28) is provided with coupling means suitable for enabling coupling of said diffuser (28) with a support and distribution element (11, 14, 14a, _L4b, 14c, 31, 37, 42, 44) according to any one of claims 1 to 29.

43. Burner according to claim 42, wherein said coupling means comprises appendages of said, diffuser (28) suitable for coupling with said further openi-ngs (12) of said support and distribution element (11, 14 14a., 14b, 14c, 31, 37, 42, 44) .

44. Burner according to any one of claims 1 to 35, or from 41 to 43, wherein said diffuser elements (2) are made of metal material.

45. Burner according to any one of claims 1 to 35, or from 41 to 43, wherein said diffuser elements (2) are made of ceramic material.

46. Burner according to any one of claims 1 to 35, or from 41 to 43, wherein said diffuser elements (2) are made of material with great resistance to the burner's operating temperatures.

47. Burner according to any one of claims 1 to 35, or from 41 to 46, wherein at least the upper face (3) of said diffuser elements (2) is made of porous material.

48. Burner according to any one of claims 1 to 35, or from 41 to 47, wherein said diffuser elements (2) are arranged on said support and distribution element (11, 14, 14a, 14b, 14c, 31) according to any arrangement configuration.