Gas burner comprising a plurality of gas ejection end pieces

Abstract

The invention relates to a gas burner (5) for an industrial furnace (1), comprising: - gas (20) and air (31) supply circuits; - a first and a second ejection end piece (41, 51), connected to a respective end of a first and a second nozzle (40, 50), extending along a respective longitudinal axis (X1, X2), and having, respectively, a first through-hole (43), oriented parallel to the first longitudinal axis (X1), and a second through-hole (53), transverse to the second longitudinal axis (X2), wherein the gas supply circuit (20) supplies gas to the ejection end pieces and comprises a first and a second gas pipe (27a, 27b) in fluid communication therewith, wherein the air supply circuit (31) supplies the first and second nozzles, and wherein the first and second ejection end pieces (41, 51) each comprise an inner portion in the first or second nozzle, respectively, and an outer portion projecting therefrom.

Description

Gas burner comprising a plurality of gas ejection nozzles

[0001] The invention relates to the field of industrial gas burners, in particular for the production of terracotta construction products (bricks, tiles). The invention also relates to industrial ovens comprising such gas burners. Technological background

[0002] For example, we know of tunnel-type gas cooking ovens subdivided into several zones: a pre-oven, a preheating zone, a cooking stage, and a cooling zone.

[0003] In an example of a tunnel kiln, a range of three different types of burners is installed:- high power jet type burners (150kW-250kW), installed on the vertical walls of the kiln in the preheating zone;- medium power jet type burners (80kW-100kW), installed on the roof of the kiln, in places requiring a high concentration of power;- low power lance type burners (30kW-80kW), in areas where the atmosphere has a temperature above 750°C.

[0004] Jet burners are used on three power levels: "all (100%), little (idle) or nothing (off)", and operate by controlled ignition, while lance burners are used on two levels: "all or nothing", and operate by self-ignition.

[0005] The design of existing gas burners limits them to the exclusive use of natural gas and LPG. In addition, their operating mode is relatively limited.

[0006] In brick and tile firing kilns, a large majority of the power used is distributed by "lance" type burners. Their design does not allow for optimizing the control mode, and in particular does not allow for modulating the heating power and / or mixing.

[0007] The operator can adjust the lances in 3 ways: - by adjusting the quantity of gas injected into the furnace (gas pressure or diameter of the gas nozzles); - by adjusting the quantity of air injected into the lance (gas with air in variable quantity or pure gas); - by choosing the flame shape by installing a coaxial ejection nozzle (axial straight jet), or a so-called "gas stove" nozzle (short radial jet).

[0008] Manual adjustment must be carried out individually on each burner for each major change in product, range, or cooking rate (number of wagons of products cooked per given period). Burner shutdowns or tip changes are sometimes necessary when they are no longer suitable for new cooking processes.

[0009] Given the large number of burners installed in a tunnel kiln, this results in significant durations, downtimes and adjustment costs.

[0010] Furthermore, energy represents a significant portion of the manufacturing costs of clay building products. It is therefore also important to optimize the use of existing gas burners.

[0011] One idea behind the invention is to provide an economical and versatile gas burner and a cooking oven incorporating such a gas burner.

[0012] Another idea behind the invention is to make it easier to adjust gas burners.

[0013] Another idea behind the invention is to optimize the energy consumption of gas burners and reduce CO2 emissions linked to the use of fossil fuels.

[0014] Another idea behind the invention is to propose a gas burner that improves cooking homogeneity and mixing of gases across the cooking channel section.

[0015] Another idea behind the invention is also to reduce the length of the useful cooking stage.

[0016] According to one embodiment, the invention provides a gas burner intended for industrial furnaces, in particular furnaces for firing terracotta products, comprising:- a cooking gas supply circuit,- an air supply circuit,- a first nozzle, the first nozzle extending along a first longitudinal axis,- a second nozzle, distinct from the first nozzle, the second nozzle extending along a second longitudinal axis, distinct from the first longitudinal axis,- a first ejection nozzle, connected to one end of the first nozzle and having a first through-orifice at its distal end, said first through-orifice being oriented parallel to the first longitudinal axis; and- a second ejection nozzle, connected to one end of the second nozzle and having at least one second through-orifice oriented transversely to the second longitudinal axis,wherein the cooking gas supply circuit is configured to supply cooking gas to the first ejection nozzle and the second ejection nozzle, the cooking gas supply circuit comprising a first gas conduit in fluid communication with the first ejection nozzle, and a second gas conduit in fluid communication with the second ejection nozzle, wherein the air supply circuit is configured to supply air to the first nozzle and / or the second nozzle, wherein the first ejection nozzle comprises an inner portion retained within the first nozzle and an outer portion projecting from the first nozzle, wherein the second ejection nozzle comprises an inner portion retained within the second nozzle and an outer portion projecting from the second nozzle.,

[0017] Thanks to these characteristics, the gas burner according to the invention makes it possible to offer at least two flame shapes in the same cooking cycle and without having to modify the ejection nozzle manually, namely a first flame shape extending axially from the first ejection nozzle, and a second flame shape extending radially, that is to say transversely to the general direction of extension of the first flame shape. Thus, it is possible with such a type of burner to alternate the flame shapes easily and without requiring manual adjustment by a user. In addition, this type of burner also makes it possible to limit the number of burners present in an oven and to optimize their usage time. The alternation between the flame shapes also has the advantage of being able to change the cooking work according to needs, in particular when implementing the same cooking process.This makes it possible to improve gas mixing, i.e. the mixing of cooking gas, air and hot gases resulting from combustion, in the oven and the homogeneity of cooking over a section of the cooking oven.

[0018] This improved cooking control offers other advantages. It allows for a reduction in the useful length of the cooking stage, if necessary. It also allows for a reduction in CO2 emissions linked to the use of fossil fuels.

[0019] Furthermore, advantageously, given its versatile structure, the gas burner according to the invention lends itself well to dimensioning for different types of gas: natural gas, biogas, LPG, syngas, hydrogen, or a mixture of several of these gases.

[0020] According to embodiments, such a gas burner may comprise one or more of the following features.

[0021] According to one embodiment, the second end piece comprises a plurality of second through holes. Optionally, these are distributed regularly around the periphery of the second end piece.

[0022] Such a plurality of second through orifices allows the gas burner to ensure gas expulsion over a significant part of its perimeter and therefore to provide good heat distribution and good thermal mixing in the oven in which the gas burner is installed.

[0023] Optionally, the second longitudinal axis is parallel to the first longitudinal axis.

[0024] Thus, the gas burner is of a most compact design.

[0025] According to one embodiment, the air supply circuit comprises a first air duct and a second air duct, the first air duct of the air supply circuit being in fluid communication with the first nozzle, and the second air duct of the air supply circuit being in fluid communication with the second nozzle.

[0026] Thus, the air supply circuit offers the possibility of varying the air flow selectively in the first nozzle and in the second nozzle according to requirements (flame shape, flame intensity, etc.).

[0027] According to one embodiment, the first gas conduit extends through the first nozzle, and the second gas conduit extends through the second nozzle.

[0028] Thus, the cooking gas supply circuit offers the possibility of varying the cooking gas flow selectively in the first nozzle and in the second nozzle according to requirements (flame shape, flame intensity, etc.).

[0029] According to one embodiment, at least one of the second ejection tip and the second nozzle comprises a first rotation restriction means allowing a determined angular positioning of the second ejection tip in the second nozzle.

[0030] Thus, the angular position of the second ejection nozzle and its at least one through-orifice can be guaranteed, thus ensuring control of the orientation of the flame, and therefore of the spatial distribution of the heat provided by the flame. Such control contributes to limiting cooking defects and cooking rejects.

[0031] According to one embodiment, the second ejection nozzle has substantially a flat outer face and an arcuate outer face, corresponding in shape to a flat inner face and an arcuate inner face that the second nozzle comprises, and in which the second ejection nozzle and the second nozzle are jointly configured to allow the second ejection nozzle to slide in the second nozzle.

[0032] This makes it easier to insert the second ejector nozzle when assembling the burner, as the angular positioning of the second nozzle is guaranteed in a simple manner, without the need for manual adjustment.

[0033] According to one embodiment, the second tip is aligned with the longitudinal axis of the second nozzle.

[0034] This makes it easier to slide the second tip into the second nozzle.

[0035] According to one embodiment, the gas burner comprises a common tube in which the first nozzle and the second nozzle extend, the outer walls of the first nozzle and the second nozzle preferably forming the outer walls of the common tube.

[0036] Thus, the very design of the gas burner allows the use of a single existing orifice through a cooking oven wall.

[0037] Advantageously, the common tube may be cylindrical in shape, preferably with a circular section.

[0038] It is thus possible to reuse the through-holes for installing gas burners in existing cooking ovens.

[0039] According to one embodiment, the first nozzle and the second nozzle are separated by a common wall, the common wall preferably being planar.

[0040] This makes the gas burner particularly compact.

[0041] According to one embodiment, the common wall comprises at least one air passage orifice, the at least one air passage orifice being configured to provide fluid communication between the first nozzle and the second nozzle.

[0042] This allows minimal air passage (leakage airflow) between the first nozzle and the second nozzle, and prevents cooking gas and / or a flame from flowing upstream into the unused nozzle, thereby protecting the gas burner body.

[0043] According to one embodiment, the position of a distal end of the first gas conduit is adjustable in a direction parallel to the first longitudinal axis relative to the first ejection nozzle, preferably between a first position and a second position in which, in the first position, an end orifice of the distal end of the first gas conduit opens into the first ejection nozzle, and, in the second position, the end orifice of the first gas conduit is located upstream of the first ejection nozzle.

[0044] It is thus possible to vary the incidence of the air flow surrounding the flame and to play on its shape and temperature.

[0045] According to one embodiment, a first distance is defined between a center of the first through-orifice and the distal end of the first nozzle in the direction of the first longitudinal axis, and a second distance is defined between a center of the at least one second through-orifice and the distal end of the first nozzle in the direction of the first longitudinal axis, the second distance being greater than the first distance

[0046] Thus, the second ejection nozzle expels the cooking gas radially beyond the first ejection nozzle, so that the first ejection nozzle does not hinder the expulsion of the gas opposite the second through-hole. This configuration therefore ensures the shape of the second flame.

[0047] According to one embodiment, the invention also provides a cooking oven comprising at least one gas burner as described above, and at least one oven wall provided with a through installation orifice, the oven wall delimiting a cooking chamber, the gas burner being installed through the oven wall in the through installation orifice, the first ejection nozzle and the second ejection nozzle being arranged projecting into the cooking chamber.

[0048] Such a cooking oven benefits from the versatility of use of the aforementioned gas burner.

[0049] Advantageously, the cooking oven comprises a plurality of gas burners and a plurality of installation through-holes corresponding to the number of gas burners of the plurality of burners, each gas burner being installed in a corresponding through-hole.

[0050] The baking oven can advantageously be a tunnel oven.

[0051] The invention also relates to a method of using a gas burner as described above, in which the method comprises the following steps: - opening the first gas duct to the circulation of a flow of cooking gas so as to supply the first ejection nozzle with cooking gas and to generate a flame at the first through-orifice, - closing the first gas duct, - opening the second gas duct to the circulation of a flow of cooking gas so as to supply the second ejection nozzle with cooking gas and to generate a flame at the second through-orifice, - closing the second gas duct.

[0052] According to a particular embodiment, in the aforementioned method of using the gas burner, the cycle of opening and closing the first gas duct and the cycle of opening and closing the second gas duct can be implemented one after the other, one before the other, or even combined sequentially each one or more times during the same cooking process.

[0053] The alternating use of these cycles contributes advantageously to the efficiency of the cooking process thanks to the alternating use of the first tip and the second tip.

[0054] According to a particular embodiment, in the method of using the gas burner, during the cycle of opening and closing the first gas duct, the first nozzle is supplied alternately: - by a leakage air flow of an absolute pressure higher than the absolute pressure in the cooking chamber at the gas burner, preferably a relative pressure less than or equal to 5 mbar, and more preferably greater than 0.1 mbar, and, - by a transport air flow of a relative pressure greater than or equal to 10 mbar, and preferably less than or equal to 0.5 bar.

[0055] Thus, the method of use allows even more versatile use of the gas burner by allowing the production of at least two types of axial flames, i.e. two cooking modes, with a transport air flow allowing the cooking gas to be conveyed or with only a leakage air flow allowing the cooking gas to be prevented from rising in the air duct.

[0056] According to a particular embodiment, in the method of using the gas burner, the air supply circuit comprising a first air duct and a second air duct, the first air duct being in fluid communication with the first nozzle, and the second air duct being in fluid communication with the second nozzle, the first nozzle and the second nozzle of the gas burner being separated by a common wall comprising at least one air passage orifice configured to provide fluid communication between the first nozzle and the second nozzle, during the opening and closing cycle of the first gas duct, the first nozzle is supplied with air alternately: - by the aforementioned leakage air flow, via the first air duct, and / or via both the second air duct and the at least one air passage orifice; or, - by the aforementioned transport air flow via the first air duct.

[0057] According to a particular embodiment, in the method of using the gas burner, during the opening and closing cycle of the first gas duct, the flow of cooking gas supplying the first ejection nozzle is alternately at a relative pressure greater than or equal to 1 bar, and at a relative pressure less than 1 bar, preferably less than 0.8 bar.

[0058] Thus, the method of use allows an even more versatile use of the gas burner by allowing the production of at least two types of axial flames, i.e. two cooking modes, by acting on the relative pressure of the gas flow passing through the first gas duct.

[0059] By playing, moreover, on both the air pressure and the gas pressure according to the aforementioned variants, at least four types of flame, that is to say four cooking modes, can be produced. Brief description of the figures

[0060] The invention will be better understood, and other objects, details, characteristics and advantages thereof will appear more clearly during the following description of several particular embodiments of the invention, given solely for illustrative and non-limiting purposes, with reference to the accompanying drawings.

[0061] The figure represents a schematic view of a cooking oven comprising a wall, and a gas burner mounted through the wall according to one embodiment;

[0062] is an enlargement of one end of the gas burner in a baking oven, showing in particular a first nozzle provided with a first ejection tip, and a second nozzle provided with a second ejection tip;

[0063] is a sectional view of the gas burner according to reference AA of the;

[0064] is an enlargement of a second ejector nozzle taken in isolation;

[0065] is a sectional view of the gas burner according to reference BB of the.

[0066] In this description, the terms "gas" and "cooking gas" are to be understood as designating a gas with a high calorific value, or a mixture of gases having such a high calorific value, and different from air, unless otherwise specified.

[0067] Lamontre an industrial firing oven 1, for example intended for firing terracotta products, not shown. The firing oven 1 may advantageously be a tunnel-type gas firing oven subdivided into several zones: a pre-oven, a preheating zone, a firing stage, and a cooling zone. The firing oven 1 comprises at least one wall 2, having at least one through-installation orifice 3. The wall 2 delimits a firing chamber 10. The wall 2 may be, without limitation, a vault wall, that is to say a ceiling wall, or a side or vertical wall of the firing oven 1. The wall 2 comprises for example a structural layer 201 and an insulating layer 202.The structural layer 201 serves as a support for the various elements of the cooking oven 1, while the insulating layer 202 makes it possible to maintain the heat in the cooking chamber 10 while protecting the metal parts of the cooking oven 1, such as the nozzles 40 and 50 described below, from the cooking heat.

[0068] The cooking oven 1 also has at least one gas burner 5.

[0069] As shown in particular in, the gas burner 5 is installed on the wall 2 through the installation through-orifice 3, so that the respective distal ends 42 and 52 of a first and a second ejection nozzle 41 and 51 that the gas burner 5 comprises are arranged projecting into the cooking chamber 10. Preferably, but not limitingly, the distal end 42 of the first ejection nozzle 41 projects by at least 10 mm into the cooking chamber 10 relative to the insulating layer 202, see. To simplify the reading of the, the insulating layer 202 is not shown there.

[0070] The description below and the accompanying set of figures describe by way of example a cooking oven 1 comprising an orifice 3 and a corresponding gas burner 5. However, the number of orifices and gas burners described is not limiting, and the cooking oven 1 may also comprise a plurality of orifices 3 and a plurality of corresponding gas burners 5. By way of non-limiting examples, the cooking oven 1 may comprise 60, 90, 120 gas burners 5, or any number appropriate to the use case, and as many corresponding orifices to accommodate them.

[0071] In the example illustrated in Figures 1 and 2, the gas burner 5 is fixed to the wall 2 by a fixing member 60. The fixing member 60 comprises a tubular section 61, receiving a tube 7, as described below, of the gas burner 5, and a plate 62, arranged against an outer face 4 of the wall 2.

[0072] The gas burner 5 comprises a cooking gas supply circuit 20, an air supply circuit 31. The gas burner 5 further comprises a first nozzle 40, a second nozzle 50, the first ejection tip 41 and the second ejection tip 51. The first nozzle 40 and the second nozzle 50 are preferably made of refractory metal. The first tip 41 and the second tip 51 are preferably made of ceramic.

[0073] The cooking gas supply circuit 20 here comprises: a first conduit 27a, a second conduit 27b, a main supply conduit 21, a high-pressure gas conduit 22, a low-pressure gas conduit 23 and a connection conduit 24.

[0074] The main supply line 21 is provided with a filter 28. The main supply line 21 supplies cooking gas, on the one hand, to the high-pressure gas line 22 and to the low-pressure gas line 23.

[0075] The high pressure gas line 22 is connected in fluid communication to the first conduit 27a. The high pressure gas line 22 has a solenoid valve 30a.

[0076] The low-pressure gas line 23 is connected in fluid communication to the second conduit 27b. The low-pressure gas line 23 here has a regulator 29, or pressure reducer, for lowering the gas pressure at its outlet, as well as a solenoid valve 30b.

[0077] The connecting line 24 also connects in fluid communication the output of the regulator 29 to the first line 27a. The connecting line has a solenoid valve 30c.

[0078] Thus, the solenoid valves 30a, 30b and 30c make it possible to selectively supply the first conduit 27a with high pressure gas, the second conduit 27b with low pressure gas, and the first conduit 27a with low pressure gas.

[0079] The air supply circuit 31 comprises a first air duct 33, a second air duct 34, and a main supply duct 32. The main supply duct 32 supplies air to the first air duct 33 and the second air duct 34. Each of the first air duct 33 and the second air duct 34 is here provided with an automated valve 35 and a manual valve 36 making it possible to regulate the air flow passing through them at will.

[0080] Each automated valve 35 is preferably a fast-acting valve. Each automated valve 35 may be, for example, but not limited to, a solenoid valve, or a pneumatic valve.

[0081] The first air duct 33 is connected in fluid communication with the first nozzle 40. The second air duct 34 is connected in fluid communication with the second nozzle 50. The air supply circuit 31 is thus configured to supply air to the first nozzle 40 and the second nozzle 50.

[0082] Each of the automated valves 35 has at least one operating state, in which it allows a flow of transport air to pass through, and one leakage state, in which it allows a flow of leakage air to pass through. The flow of transport air allows the cooking gas to be conveyed, i.e. the respective flame to be given the desired shape. The flow of leakage air prevents the cooking gas and / or the flame from rising upstream into the corresponding unused nozzle and air duct, thereby protecting the gas burner 5.

[0083] As seen in Figures 1 and 2, the first nozzle 40 extends along a first longitudinal axis X1. The second nozzle 50 extends along a second longitudinal axis X2, distinct from the first longitudinal axis X1, in other words not coaxial with the first longitudinal axis X1. More specifically, in the embodiment shown, the second longitudinal axis X2 is parallel to the longitudinal axis X1.

[0084] The first nozzle 40 and the second nozzle 50 extend into the aforementioned cylindrical tube 7, which therefore forms a common tube. Preferably, as illustrated, the outer walls of the first nozzle 40 and the second nozzle 50 form the outer walls of the common tube 7. The first nozzle 40 and the second nozzle 50 are separated by a common wall 71, as illustrated in particular in FIGS. 3 and 5. Preferably, the common wall 71 is flat.

[0085] In a particular embodiment, illustrated in, the common wall 71 comprises at least one air passage orifice 72, preferably a plurality of air passage orifices 72. The air passage orifice(s) 72 is (are) configured to provide a fluid connection between the first nozzle 40 and the second nozzle 50. A minimal air passage (called leakage air flow) is thus permitted between the first nozzle 40 and the second nozzle 50, and makes it possible to prevent the cooking gas and / or the flame from rising upstream in the one of the two nozzles which is unused, thus protecting the gas burner 5.

[0086] When the first gas duct 27a is open to the circulation of a cooking gas flow, the first nozzle 40 can thus be selectively supplied: - by the aforementioned leakage air flow; - by a transport air flow.

[0087] The supply of the first nozzle 40 by the leak air flow is preferably, but not limited to, carried out via the first air duct 33. The automated valve 35 of the first air duct 34 is then open and in the leak state. In a variant not shown, a bypass duct of the automated valve 35, not shown, is for example provided. A manual valve or an automatic valve can then be provided on the bypass duct, to allow the passage of the leak air flow at the desired pressure. The automated valve 35 of the first air duct 34 is then preferably in the closed state.

[0088] In another embodiment, the supply of the first nozzle 40 by the leakage air flow can be carried out via both the second air duct 34 and the at least one air passage orifice 72, the automated valve 35 of the second air duct 34 being open. The automated valve 35 of the first air duct 33 is then preferably closed.

[0089] The supply of the first nozzle 40 by the transport air flow can be carried out via the first air duct 33, the automated valve 35 of the first air duct 33 being open.

[0090] The first ejection tip 41 is connected to one end of the first nozzle 40. The first ejection tip 41 has a first through-orifice 43 at its distal end 42. Said first through-orifice 43 is oriented parallel to the first longitudinal axis X1. With such a configuration, the first ejection tip 41 makes it possible to produce a flame of general orientation along the first longitudinal axis X1, called for example a “longitudinal” or “axial” flame.

[0091] As illustrated in, an inner portion 410 of the first ejection tip 41 is configured to be retained inside the first nozzle 40. An outer portion 411 of the first ejection tip 41 is configured to protrude from the first nozzle 40. For this purpose, a stop 412, here in the form of a lug, is formed at the junction between the inner 410 and outer 411 portions of the first ejection tip 41. The stop 412 comes into contact with an end wall 440 of the first nozzle 40.

[0092] In variants not shown, the shape of the stop 412 is different. The stop may, for example, be in the form of a semicircular crown, a plurality of fingers, etc.

[0093] The second ejection tip 51 is connected to one end of the second nozzle 50. The second ejection tip 51 has at least one second through-orifice 53 at its distal end 52, oriented transversely to the second longitudinal axis X2. With such a configuration, the second ejection tip 51 makes it possible to produce a flame with a general orientation transverse to the second longitudinal axis X2, called for example a “radial” flame. In a variant not illustrated, the second ejection tip 51 may comprise a plurality of second through-orifices 53: two, three, or more. The plurality of second through-orifices 53 may then, without limitation, be distributed regularly around the periphery of the second ejection tip 51.

[0094] As illustrated in Figures 2 and 4, an internal portion 510 of the second ejection tip 51 is configured to be retained inside the second nozzle 50. An external portion 511 of the second ejection tip 51 is configured to protrude from the second nozzle 50. For this purpose, a stop 512, here in the form of a lug, visible in, is formed at the junction between the internal 510 and external 511 portions of the second ejection tip 51. In the example illustrated, the stop 512 comes into contact with an end wall 540 of the second nozzle 50, here common with the aforementioned end wall 440 of the first nozzle 40.

[0095] In variants not shown, the shape of the stop 512 is different. The stop 512 may for example be in the form of a semi-circular crown, a plurality of fingers, etc.

[0096] An outer section of the second ejection nozzle 51 may be provided to match in shape an inner section of the second nozzle 50. The outer section of the second ejection nozzle 51 and the inner section of the second nozzle 50 may then be jointly configured to limit, preferably prevent, rotation of the second ejection nozzle 51 about its own longitudinal axis.

[0097] For this purpose, at least one of the second ejection tip 51 and the second nozzle 50 comprises a first rotation restriction means 55, 65 allowing a determined angular positioning of the second ejection tip 51 in the second nozzle 50.

[0098] In the illustrated embodiment, the second ejection nozzle 51 has substantially a flat outer face 55 and an arcuate outer face 56, see Figures 4 and 5. The flat outer face 55 and the arcuate outer face 56 are here in shape correspondence with a flat inner face 65 and an arcuate inner face 66 that the second nozzle 50 comprises. The second ejection nozzle 51 and the second nozzle 50 are jointly configured to allow the second ejection nozzle 51 to slide in the second nozzle 50.

[0099] Optionally, by analogy with the second ejection nozzle 51 and as illustrated in, the first ejection nozzle 41 here has substantially a flat outer face 45 and an arcuate outer face 46. The flat outer face 45 and the arcuate outer face 46 are then in shape correspondence with a flat inner face and an arcuate inner face that the first nozzle 40 comprises. The first ejection nozzle 41 and the first nozzle 40 are then jointly configured to allow the first ejection nozzle 41 to slide in the first nozzle 40.

[0100] With the configuration described above, the cooking gas supply circuit 20 is configured to supply cooking gas to the first ejection nozzle 41 and the second ejection nozzle 51. For this purpose, the aforementioned first gas conduit 27a is connected in fluid communication with the first ejection nozzle 41. The second gas conduit 27b is connected in fluid communication with the second ejection nozzle 51.

[0101] Structurally, the first gas conduit 27a is arranged to extend through the first nozzle 40, as shown in. The second gas conduit 27b is arranged to extend through the second nozzle 50.

[0102] In the embodiment illustrated in figures 1 and 2, the position of a distal end 48, referenced in, of the first gas conduit 27a is adjustable parallel to the first longitudinal axis X1 relative to the first ejection nozzle 41. Preferably, this adjustment is possible between a first position J and a second position K in which:- in the first position J, an end orifice 47a of the distal end 48 of the first gas conduit 27a opens into the first ejection nozzle 41, and- in the second position K, the end orifice 47a of the first gas conduit 27a is located upstream of the first ejection nozzle 41.

[0103] Positions J and K are illustrated by way of non-limiting example in.

[0104] Here, an end orifice 47b of the second gas conduit 27b preferably, but not limited to, opens into the second ejection nozzle 51.

[0105] Furthermore, as illustrated in, a first distance H1 is defined between a center of the first through-orifice 43 and the distal end 44 of the first nozzle 40 in the direction of the first longitudinal axis X1. A second distance H2 is defined between a center of the at least one second through-orifice 53 and the distal end 44 of the first nozzle 40 in the direction of the first longitudinal axis X1. The second distance H2 is greater than the first distance H1.

[0106] The cooking oven 1 and its gas burner 5 as described above can be used to allow, during the same cooking process:

[0107] - an opening of the first gas duct 27a to the circulation of a flow of cooking gas so as to supply the first ejection nozzle 41 with cooking gas and to generate a flame at the first through-orifice 43,- a closing of the first gas duct 27a,- an opening of the second gas duct 27b to the circulation of a flow of cooking gas so as to supply the second ejection nozzle 51 with cooking gas and to generate a flame at the second through-orifice 53,- a closing of the second gas duct 27b.

[0108] The cycle of opening and closing the first gas duct 27a and the cycle of opening and closing the second gas duct 27b can be implemented one after the other, one before the other, or even combined each one or more times during the same cooking process.

[0109] The first flame form flame may be the aforementioned axial flame, while the second flame form flame may be the radial flame.

[0110] In order to implement the baking oven 1 and / or the gas burner 5 described above, the baking oven 1 and / or the gas burner 5 may comprise a programmable controller 6, see. Here, for reasons of readability, the programmable controller 6 is illustrated as being connected exclusively to the solenoid valve 30b. It should be understood that the programmable controller 6 may just as well also be connected to the solenoid valves 30a and 30c, as well as to the regulator 29 and to the automated valves 35.

[0111] The programmable controller 6 can advantageously be configured to work in pulses. In such pulse work, the opening / closing cycles of the solenoid valves 30a, 30b and 30c and the automated valves 35 can be very fast. The pulses, i.e. the time during which a solenoid valve 30a, 30b or 30c, or an automated valve 35 remains open, can be set to each last between 1 millisecond and a few seconds, for example 10, 7 or 5 seconds. Such pulse work makes it possible to sequence the use of the solenoid valves 30a, 30b and 30c and the automated valves 35, which allows the gas burner 5 to improve the mixing in the baking oven 1.

[0112] Although the invention has been described in connection with several particular embodiments, it is obvious that it is in no way limited thereto and that it includes all technical equivalents of the means described as well as their combinations if these fall within the scope of the invention.

[0113] The use of the verb "comprise", "comprise" or "include" and its conjugated forms does not exclude the presence of other elements or other steps than those set out in a claim.

[0114] In the claims, any reference sign in parentheses cannot be interpreted as a limitation of the claim.

Claims

Gas burner intended for industrial ovens (1), in particular ovens for cooking terracotta products, comprising:- a cooking gas supply circuit (20),- an air supply circuit (31),- a first nozzle (40), the first nozzle (40) extending along a first longitudinal axis (X1),- a second nozzle (50), distinct from the first nozzle (40), the second nozzle (50) extending along a second longitudinal axis (X2), distinct from the first longitudinal axis (X1),- a first ejection nozzle (41), connected to one end of the first nozzle (40) and having a first through-orifice (43) at its distal end (42), said first through-orifice (43) being oriented parallel to the first longitudinal axis (X1); and- a second ejection nozzle (51), connected to one end of the second nozzle (50) and having at least one second through-orifice (53) oriented transversely to the second longitudinal axis (X2),wherein the cooking gas supply circuit (20) is configured to supply cooking gas to the first ejection nozzle (41) and the second ejection nozzle (51), the cooking gas supply circuit (20) comprising a first gas conduit (27a) in fluid communication with the first ejection nozzle (41), and a second gas conduit (27b) in fluid communication with the second ejection nozzle (51), wherein the air supply circuit (31) is configured to supply air to the first nozzle (40) and / or the second nozzle (50), wherein the first ejection nozzle (41) comprises an inner portion retained inside the first nozzle (40) and an outer portion projecting from the first nozzle (40), wherein the second ejection nozzle (51) comprises an inner portion retained inside the second nozzle (50) and an external portion projecting from the second nozzle (50)., A gas burner according to claim 1, wherein the air supply circuit (31) comprises a first air duct (33) and a second air duct (34), the first air duct of the air supply circuit (31) being in fluid communication with the first nozzle (40), and the second air duct of the air supply circuit (31) being in fluid communication with the second nozzle (50). A gas burner according to claim 1 or claim 2, wherein the first gas conduit (27a) extends through the first nozzle (40), and the second gas conduit (27b) extends through the second nozzle (50). Gas burner according to one of the preceding claims, wherein at least one of the second ejection nozzle (51) and the second nozzle (50) comprises a first rotation restriction means (55, 65) allowing a determined angular positioning of the second ejection nozzle (51) in the second nozzle (50). Gas burner according to the preceding claim, in which the second ejection nozzle (51) has substantially a flat outer face (55) and an arcuate outer face (56), in shape matching a flat inner face (65) and an arcuate inner face (66) that the second nozzle (50) comprises, and in which the second ejection nozzle (51) and the second nozzle (50) are jointly configured to allow sliding of the second ejection nozzle (51) in the second nozzle (50). Gas burner according to one of the preceding claims, wherein the gas burner comprises a common tube (7) in which the first nozzle (40) and the second nozzle (50) extend, the outer walls of the first nozzle (40) and the second nozzle (50) preferably forming the outer walls of the common tube (7). Gas burner according to one of the preceding claims, wherein the first nozzle (40) and the second nozzle (50) are separated by a common wall (71), the common wall (71) preferably being planar. Gas burner according to one of the preceding claims, wherein the position of a distal end (48) of the first gas duct (27a) is adjustable in a direction parallel to the first longitudinal axis (X1) relative to the first ejection nozzle (41), preferably between a first position (J) and a second position (K) in which, in the first position (J), an end orifice (47a) of the distal end (48) of the first gas duct (27a) opens into the first ejection nozzle (41), and, in the second position (K), the end orifice (47a) of the first gas duct (27a) is located upstream of the first ejection nozzle (41). Gas burner according to one of the preceding claims, wherein a first distance (H1) is defined between a center of the first through-orifice (43) and the distal end (44) of the first nozzle (40) in the direction of the first longitudinal axis (X1), and a second distance (H2) is defined between a center of the at least one second through-orifice (53) and the distal end (44) of the first nozzle (40) in the direction of the first longitudinal axis (X1), the second distance (H2) being greater than the first distance (H1). Cooking oven (1) comprising at least one gas burner (5) according to one of the preceding claims, and at least one oven wall (2) provided with an installation through-hole (3), the oven wall (2) delimiting a cooking chamber (10), the gas burner (5) being installed through the oven wall (2) in the installation through-hole (3), the first ejection nozzle (41) and the second ejection nozzle (51) being arranged projecting into the cooking chamber (10). Method for using a gas burner (5) according to one of claims 1 to 9 wherein the method comprises the following steps: - opening the first gas duct (27a) to the circulation of a flow of cooking gas so as to supply the first ejection nozzle (41) with cooking gas and to generate a flame at the first through-orifice (43), - closing the first gas duct (27a), - opening the second gas duct (27b) to the circulation of a flow of cooking gas so as to supply the second ejection nozzle (51) with cooking gas and to generate a flame at the second through-orifice (53), - closing the second gas duct (27b).

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