阅读说明：本技术 燃气燃烧器 (Gas burner ) 是由 马西莫·多拉 于 2020-03-30 设计创作，主要内容包括：一种用于炉灶面的燃气燃烧器(1),其包括：至少一个外部环形火焰扩散器(6a),其具有混合物的相应环形分配室(5)；用于所述燃料气体的至少一个第一流体入口(2a)；至少一个第一轴向文丘里混合器(3a),其配置成作为输入接收来自所述第一流体入口(2a)的所述气体和来自第一大气入口(4a)的一次空气；所述至少一个环形分配室(5)通过离开第一文丘里混合器(3a)的所述燃料混合物的分隔室(70)流体连接到所述第一文丘里混合器(3a),所述分隔室(70)流体连接到至少两个流体通道(71,72),其将所述第一文丘里混合器(3a)连接到所述外部环形火焰扩散器(6)的所述环形分配室(5)的相对于所述第一文丘里混合器(3a)相对布置的两个区域；以及至少一个点火装置(10),其用于点燃离开所述外部火焰扩散器(6a)的所述混合物,并且其中,考虑到在使用状态下的所述燃烧器(1)的平面图,所述外部环形火焰扩散器(6a)限定具有质心(G)的几何图形(F),并且其中正交于所述平面图并穿过所述质心(G)的轴线(A)在所述第一文丘里混合器(3a)的外部。(A gas burner (1) for a cooktop, comprising: at least one outer annular flame diffuser (6a) having a respective annular distribution chamber (5) of the mixture; at least one first fluid inlet (2a) for the fuel gas; at least one first axial venturi mixer (3a) configured to receive as inputs said gas from said first fluid inlet (2a) and primary air from a first atmospheric air inlet (4 a); said at least one annular distribution chamber (5) being fluidly connected to a first venturi mixer (3a) by a separation chamber (70) of the fuel mixture exiting said first venturi mixer (3a), said separation chamber (70) being fluidly connected to at least two fluid channels (71, 72) connecting said first venturi mixer (3a) to two regions of said annular distribution chamber (5) of said outer annular flame diffuser (6) arranged opposite with respect to said first venturi mixer (3 a); and at least one ignition device (10) for igniting the mixture exiting the outer flame diffuser (6a), and wherein the outer annular flame diffuser (6a) defines a geometric figure (F) having a centroid (G) taking into account a plan view of the burner (1) in use, and wherein an axis (a) orthogonal to the plan view and passing through the centroid (G) is external to the first venturi mixer (3 a).)

1. A gas burner (1) for a cooktop, comprising: at least one outer annular flame diffuser (6a) having a respective annular distribution chamber (5) of the mixture; at least one first fluid inlet (2a) for fuel gas; at least one first axial venturi mixer (3a) configured to receive as inputs the gas from the first fluid inlet (2a) and primary air from a first atmospheric air inlet (4a), the at least one annular distribution chamber (5) being connected to the first venturi mixer (3a) through a separation chamber (70) of the fuel mixture exiting the first venturi mixer (3a), the separation chamber (70) being fluidly connected to at least two fluid channels (71, 72), the at least two fluid channels (71, 72) connecting the first venturi mixer (3a) to two regions of the annular distribution chamber (5) of the outer annular flame diffuser (6a), the two regions being arranged opposite with respect to the first venturi mixer (3 a); and at least one ignition device (10) for igniting the mixture exiting the outer flame diffuser (6a), and wherein the outer annular flame diffuser (6a) defines a geometric figure (F) having a centroid (G) taking into account a plan view of the burner (1) in use, and wherein an axis (a) orthogonal to the plan view and passing through the centroid (G) is external to the first venturi mixer (3 a).

2. Burner (1) according to claim 1, wherein said fluid channel (71, 72) has an end opening (71a, 72a) for injecting said mixture in said at least one distribution chamber (5), said end opening (71a, 72a) of said fluid channel (71, 72) being arranged substantially symmetrically with respect to a plane comprising said axis (a).

3. Burner (1) according to claim 1 or 2, comprising at least one second fluid gas inlet (2b), said first fluid inlet (2a) being fluidly connected to said first venturi mixer (3a) and the second fluid gas inlet (2b) being connected to a second venturi mixer (3b), said second venturi mixer (3b) being arranged outside said axis (a) so as to surround said axis (a).

4. A burner according to claim 3, characterised in that said second venturi (3b) comprises at least one substantially vertically arranged portion (30 b).

5. Burner (1) according to claim 1 or 2, characterized by comprising at least one annular chamber (73) arranged outside said axis (a) so as to surround said axis (a) and fluidly connected to said fluid channels (71, 72).

6. Burner according to at least claim 5, characterized by comprising one or more internal flame diffusers (6b) provided with at least one respective distribution chamber (5'), said respective distribution chamber (5') being fluidly connectable to said distribution chamber (5) of said external flame diffuser (6a) by means of a duct, wherein said first venturi (3a) feeds said distribution chambers (5, 5') of both said at least one external flame diffuser (6a) and said internal flame diffuser (6 a).

7. A burner according to claim 6, characterized in that said duct connecting said respective distribution chamber (5') to said distribution chamber (5) of said outer flame diffuser (6a) comprises said annular chamber (73), said annular chamber (73) being fed by said fluid channels (71, 72) and being fluidly connected to said fluid channels (71, 72) so that a portion of the mixture flowing through said fluid channels (71, 72) is directed to said annular chamber (73).

8. Burner (1) according to any one of the preceding claims, comprising a housing (8) for a temperature sensor (9) arranged at said axis (A).

9. Burner (1) according to any one of the preceding claims, characterized in that said first venturi mixer (3a) has a substantially horizontal Axis (AV).

10. The burner (1) according to claim 9 when depending on claim 8, characterized in that said housing (8) is arranged so that there is at least one plane orthogonal to said orthogonal axis, so that said at least one plane intersects both said first venturi mixer (3a) and said housing (8).

11. Burner according to claim 9 or 10 when depending on claims 4 and 8, wherein said housing (8) is arranged substantially concentrically with said at least one portion (30b) of said second venturi mixer (3 b).

12. Burner according to claim 11, wherein said vertical portion (30b) is arranged around said orthogonal axis (a) so that said second venturi (3b) adapted to allow the passage of the mixture defines a space outside said orthogonal axis (a) and thus around said orthogonal axis (a).

13. Burner according to claim 12, wherein said portion of said second venturi (3b) comprises at least one outer wall (31b) and one inner wall (32b) arranged inside said inner wall (31b), said housing (8) being defined by the inner wall (32b) of said portion of said second venturi (3 b).

14. A burner according to claim 8 when depending on one or more of claims 5 to 7, characterized in that said housing (8) is defined by an inner wall of said annular chamber (73).

15. Burner (1) according to any of the preceding claims, characterized by a temperature sensor (9) arranged in the housing (8).

Technical Field

The present invention relates to the field of domestic gas burners, in particular gas burners for domestic cooktops.

Here and in the following, the term "domestic cooktop" refers to any external surface intended to house one or more atmospheric gas burners, whether belonging to a so-called built-in cooktop, a set of domestic cooking appliances or any other domestic cooking appliance.

Background

In the field of atmospheric gas burners for cooktops, the use of safety devices has long been known in order to determine the presence of a flame by means of a thermocouple connected to a special safety valve, and to determine the temperature reached by the burner by means of a temperature sensor also connected to, for example, a gas valve.

These temperature sensors or probes can be arranged at the flame diffuser of the burner in order to detect the temperature at the cooking vessel placed on the gas burner and generally have the purpose of preventing an excessive temperature rise, for example when there is no liquid in the cooking vessel, and/or to keep the temperature of the above-mentioned cooking vessel as constant as possible, essentially acting as a thermostat connected to the gas supply valve.

In particular, it is known to arrange a temperature probe within a gas burner for cooktops, so that it can be brought into contact with or otherwise placed adjacent to the bottom of a cooking container (such as a pan or wok), in order to detect the temperature of the cooking container and prevent the situation of excessive dry heat of the same cooking container when the sensor is connected to a shutter on, for example, an air supply control valve.

In high-power burners, or in any case in gas burners for cooktops equipped with at least one annular flame diffuser, and therefore in which there is a venturi mixer whose size is not necessarily small, the axis along which the venturi mixer extends must be far from the axis along which the temperature probe is positioned, due to the bulkiness, and the former cannot intersect the latter.

It should be noted that the term "annular" in this context generally means that the flame diffuser of the burner and the respective distribution chamber of the fuel mixture are arranged according to a closed line around a volume of atmosphere and preferably have only a circular shape, and therefore in this case the annular flame diffuser is substantially toroidal, but can also have an elliptical or rectangular shape or any other shape suitable for making a flame diffuser potentially allowing to obtain at least one ring of flames facing the central axis of the same burner.

It should also be noted that here and in the following, the term "venturi mixer" means a mixer comprising a venturi, i.e. equipped with a diverging portion, in which the fluid can be gradually expanded at least before a narrow section, which in turn can be before a gradually converging portion, in which the injector delivers a flow of pressurized fuel gas, so that primary air (primary air) is drawn upstream of the narrow section or converging portion (if any) and mixed with the fuel gas. The venturi may be of the axial type with horizontal or vertical symmetry (in other words comparable to a conventional longitudinally extending venturi), or of the radial type, as described in DE 3123751 a.

US2019/0017710a1 describes an atmospheric pressure gas burner for cooktops comprising an annular flame diffuser with a respective distribution chamber and an axial venturi mixer with a horizontal axis, and in which at the outer periphery of the flame diffuser there are temperature probes arranged along an axis parallel to the central symmetry axis of the burner. Due to its eccentric position with respect to the centre of the burner itself, the eccentric position of the temperature probe is not the most suitable for correctly detecting the temperature of the cooking vessel arranged on the burner.

In order to better detect the temperature of a cooking vessel placed on top of such a burner equipped with at least one annular diffuser, it is known to arrange a temperature probe in the central position of the burner, generally along the central symmetry axis (vertical symmetry axis) of the burner itself.

In this case, at least the respective venturi mixer feeding the annular flame diffuser must be arranged asymmetrically with respect to the central symmetry axis of the burner, so that its own longitudinal extension axis is distant from the central symmetry axis of the aforementioned burner and does not intersect the latter.

The CN107702100A patent describes a gas burner of the partially aerated type for cooktops, comprising an outer annular flame diffuser with two flame rings and a central annular flame diffuser with one flame ring, and equipped, within the volume enclosed by the central annular flame diffuser, with temperature probes arranged along the central (vertical) symmetry axis of the burner. The burner also comprises two substantially horizontally extending venturi mixers of the axial type, the symmetry axes of which are arranged at the sides of the vertical central symmetry axis of said burner and on a line substantially orthogonal to the vertical central symmetry axis of said burner. One of these venturi mixers feeds the distribution chamber of the outer annular flame diffuser with two flame rings, while the other feeds the distribution chamber of the central flame diffuser with one flame ring, the latter being concentric with the former.

CN107702100 provides that when the fuel mixture is fed from the outlet section of the respective venturi mixer (i.e. from this section at the end of the diverging portion) to the distribution chamber, the mixture flows directly into this distribution chamber of the flame diffuser.

This generally results in an uneven distribution of the fuel mixture in the annular flame diffuser and in a possible non-uniformity of the flame formed in the flame ring of the annular flame diffuser.

Disclosure of Invention

It is therefore an object of the present invention to provide a gas burner for domestic use, in particular an atmospheric pressure gas burner for cooktops, which allows the use of temperature probes without affecting the performance of the burner itself.

These and other objects are achieved by a household gas burner according to one or more of the appended claims.

In particular, the object of the invention is a gas burner according to claim 1. Preferred aspects are set out in the dependent claims.

According to an aspect of the invention, a gas burner for a cooktop comprises: at least one outer annular flame diffuser having a respective annular distribution chamber of the mixture; at least one first fluid inlet for fuel gas; at least one first axial venturi mixer configured to receive as inputs the gas from the first fluid inlet and primary air from a first atmospheric air inlet. The annular distribution chamber is fluidly connected to the first venturi mixer by a compartment of the fuel mixture exiting the first venturi mixer. The separation chamber is fluidly connected to at least two fluid passages connecting the first venturi mixer to two regions of the annular distribution chamber of the outer annular flame diffuser, which are oppositely arranged with respect to the first venturi mixer. The burner also includes at least one ignition device to ignite the mixture exiting the flame diffuser. Furthermore, considering the plan view of the burner in use, the external flame diffuser defines a geometry having a centroid and an axis orthogonal to the plan view and passing through said centroid is external to the first venturi mixer.

The "eccentric" positioning of the first venturi mixer allows elements such as sensors, in particular temperature sensors, to be arranged at the centre of the burner without interfering with the first venturi mixer itself.

Furthermore, thanks to the separation chamber and the fluid passage, the distribution of the mixture to the distribution chamber (or chambers) occurs in a uniform manner, even if the first mixer is arranged "off-centre" with respect to the burner itself.

It should be noted that the duct allowing the entry of primary air may be obtained (at least partially) in the burner or in the cooktop to which the burner is intended to be coupled.

It is further known to provide not only burners configured to draw primary air from the environment above the cooktop, but also burners configured to draw primary air from the environment below the cooktop.

Embodiments of the invention are provided for two solutions, namely a burner that draws primary air from above the cooktop and a burner that draws primary air from below the cooktop.

Flame diffusers are also known as "outer" and "annular". The definition of "annular" has been discussed previously.

The term "outer" means that if the burner has more than one flame diffuser, the field technician will clearly understand that the outer flame diffuser is the larger flame diffuser that surrounds the other flame diffusers. In the case of a single flame diffuser, the flame diffuser acts as an external flame diffuser.

According to an aspect of the invention, the fluid channel, which is normally arranged downstream of the venturi mixer, has an end opening to inject the mixture into the distribution chamber, when considering the direction of feed of the mixture under normal conditions of use of the burner. The end openings are arranged substantially symmetrically with respect to a plane comprising the above-mentioned orthogonal axis. Typically, not only the end opening, but also the end portion of the fluid channel (i.e. the portion of the fluid channel equipped with such an end opening) is symmetrical with respect to the plane.

Typically, the outer flame diffuser has a substantially circular perimeter in plan view.

The first venturi mixer is arranged with a substantially horizontal axis, wherein "substantially" means that the axis of the first venturi mixer is typically an inclined axis at an angle of less than 40 degrees, typically less than 30 degrees, with respect to the horizontal plane, taking into account the conditions of use of the burner.

Thus, the orthogonal axis is located at the center of the circumference defined by the outer flame diffuser.

Thus, the axis of the first venturi mixer (projected on a plan view of the burner in use) is placed at the chord of the circumference, i.e. at a straight line intersecting the circumference without passing through its centre.

According to an aspect of the invention, the burner comprises at least two fluid gas inlets. The first fluid inlet is fluidly connected to the first axial venturi mixer, typically to feed an external flame diffuser. The second fluid gas inlet is connected to a second venturi mixer, also generally axial, preferably for feeding a second flame diffuser. The second venturi mixer is arranged outside the orthogonal axis so as to surround the orthogonal axis.

According to a different possible aspect, the burner comprises an annular chamber arranged outside the orthogonal axis so as to surround the orthogonal axis and fluidly connected to the fluid passage. In these embodiments, there may be a single venturi mixer (i.e., the first-mentioned venturi mixer) to feed several flame diffusers.

In particular, according to another aspect of the invention, the burner comprises one or more internal or central flame diffusers equipped with at least one respective distribution chamber which can be fluidly connected to the distribution chamber of said external flame diffuser by means of a duct. Advantageously, said first venturi feeds the distribution chamber of said at least one outer flame diffuser and of said one or more inner flame diffusers.

Also, the duct connecting the respective distribution chamber of the one or more inner flame diffusers to the distribution chamber of the outer flame diffuser comprises the annular chamber, wherein the annular chamber is fed by and fluidly connected to the fluid channel such that part of the mixture flowing through the fluid channel is directed to the annular chamber (73).

As mentioned above, the first axial venturi mixer is arranged such that its axis is substantially horizontal.

In an embodiment with two venturi mixers, the second venturi mixer is preferably arranged such that at least a portion thereof is arranged substantially vertically (i.e. at an angle of more than 70 °) in the situation of use.

According to one aspect, the burner comprises a housing for the temperature sensor or probe arranged at the orthogonal axis. Preferably, the temperature sensor is arranged in the housing. This embodiment can be used in the case of a burner with a single venturi mixer and with two venturi mixers.

According to a possible aspect, the housing is arranged so that there is at least one such plane: which is orthogonal to the orthogonal axis (i.e. a plane which is generally horizontal when the burner is in use) and which is capable of intersecting both the first venturi mixer having a substantially horizontal axis and the housing.

According to a particular aspect of the invention, the housing is arranged substantially concentrically with the at least a portion of the second venturi mixer.

This configuration offers the advantage of reducing the number of components constituting the burner, since the sensor inside the casing no longer needs to be protected by a special shield having only this specific function or made on the cover, but the casing for the temperature sensor is obtained with the wall of a portion of the second mixer. Preferably, the vertical portion is arranged around the orthogonal axis such that the second venturi adapted to allow passage of the mixture defines a space outside the orthogonal axis, thereby surrounding the orthogonal axis. In particular, said portion of the second venturi comprises at least one outer wall and one inner wall arranged inside said inner wall; the housing is defined by an inner wall of the portion of the second venturi.

On the other hand, in the case of a single venturi mixer, the housing is defined by the inner wall of the annular chamber.

Such a configuration offers the advantage of reducing the number of components constituting the burner, as in the case of two different venturi mixers, since the sensor inside the housing no longer needs to be protected by a special shield having only this specific function or made on the cover, but the housing for the temperature sensor is obtained with the walls of the mixing chamber for the burner with a single venturi mixer.

In all cases, a temperature sensor is arranged in the housing.

Drawings

Exemplary and non-limiting embodiments of the invention will be described hereinafter with reference to the accompanying drawings, in which:

fig. 1 is a perspective view of a burner according to an embodiment of the invention;

FIG. 2 is a perspective view similar to FIG. 1, with the flame diffuser removed;

figure 3A is a bottom view of the burner of figure 1;

FIG. 3B is a schematic plan view of the burner of FIG. 1, with the position of the first venturi mixer highlighted and oriented to rotate so as to be comparable to that shown in FIG. 3A;

figure 4 is a bottom perspective view of the burner of figure 1;

FIG. 5 is a cross-sectional view of a burner according to an embodiment alternative to that of FIG. 1, in which the position of the second gas inlet has been changed;

FIG. 6 is a perspective view of a burner according to an embodiment alternative to that of FIG. 1, in which the primary air inlet has been modified;

figures 7A and 7B are perspective views of an alternative embodiment of the invention, equipped with a single venturi mixer.

Detailed Description

The domestic gas burner 1 comprises at least one first fluid gas inlet 2a (hereinafter also referred to as "first inlet 2 a") which supplies gas to a first axial venturi mixer 3A (hereinafter also referred to as "first venturi 3A"), as can be seen for example in fig. 3A-5.

The burner 1 and/or a cooking top (not shown in detail) on which the burner 1 is mounted are configured to form an inlet 4a for primary air (hereinafter also referred to as "first air inlet 4 a") in order to form a mixture within the first venturi 3 a. In the embodiment shown, the first air inlet 4a is formed on the burner 1.

In particular, there are possible embodiments of sucking primary air from above the cooktop, such as the embodiments shown in fig. 1-4, and possible embodiments of sucking primary air from below the cooktop, such as the embodiment shown in fig. 6.

The first venturi 3a preferably has a substantially horizontal axis AV, i.e. an inclined axis AV at an angle of less than 40 °, typically less than 30 °, with respect to the horizontal plane (taking into account the normal use conditions of the burner).

The first venturi 3a communicates with one or more distribution chambers 5, said distribution chambers 5 being adapted to distribute the gas-air mixture to an external flame diffuser 6a, which external flame diffuser 6a is configured in a manner known in the art to allow the outflow of the gas mixture adapted to be burnt. The distribution chamber 5 is delimited by a flame diffuser 6a, i.e. it is formed in the space on top delimited by the flame diffuser 6 a. One or more internal flame diffusers 6b may also be provided in a known manner. These inner flame diffusers 6b generally have respective distribution chambers 5', the respective distribution chambers 5' being fluidly connectable to the distribution chamber 5 of the outer flame diffuser 6a by means of pipes. The outer flame diffuser 6a defines a geometric pattern F, typically a circumference, in plan view.

The geometry F is shown in detail in fig. 3B. It should be noted that for ease of viewing, the plan view in fig. 3B has been oriented and rotated so as to be comparable to the orientation of the elements shown in fig. 3A, which shows a bottom view of the burner 1.

The geometry F shows a centre of mass G, which does not intersect the first venturi 3A, i.e. the axis a is outside the first venturi 3A, taking into account an orthogonal axis a (hereinafter also referred to as "axis a") passing through the centre of mass G (i.e. orthogonal to the views of fig. 3A and 3B).

In a simplified manner, considering a plan view or in any case a horizontal plane of the burner 1 in the condition of use, the centroid G (representing the projection of the axis a on this view or horizontal plane) is external to the projection of the first venturi 3a on this view or horizontal plane, as schematically illustrated in fig. 3B.

The first venturi 3a has at least two fluid passages 71, 72 for supplying a gas-air mixture to the distribution chamber 5. The fluid channels 71, 72 are arranged opposite to the first venturi 31, i.e. the first venturi 3a is substantially interposed between the fluid channels 71, 72.

Both fluid channels 71, 72 have end openings 71a, 72a allowing the mixture to enter the distribution chamber 5.

The end openings 71a, 72a are preferably symmetrical with respect to a plane P (schematically shown in fig. 5) comprising the axis a.

The end openings 71a, 72a are arranged at the ends of the end portions 71b, 72b of the respective fluid channels 71, 72. Preferably, the end portions 71b, 72b are also symmetrical with respect to the same plane P.

According to the invention, the first venturi 3a terminates in a compartment 70, the compartment 70 being connected to two fluid passages 71, 72. It should be noted that in the first production step, the compartment 70 is formed open to the outside environment for ease of production. Then, a covering element 70b is applied to the compartment 70 in order to allow the mixture to flow towards the fluid channels 71, 72, thereby preventing the mixture from being dispersed in the environment.

According to a possible aspect of the invention, the compartment 70 is configured to initially divert the flow away from the first venturi 3a in a substantially radial direction.

Generally, the compartment 70 is connected to an initial portion 71c of the first fluid duct 71 (as shown in the figures, in turn connected directly or indirectly to a respective end portion 71b of the respective duct 71), and to an end portion 72b of a second fluid duct 72 of the aforementioned fluid ducts 71, 72.

According to a preferred aspect, as in the embodiment shown in the figures, the burner 1 comprises at least one second venturi mixer 3b (hereinafter also referred to as "second venturi 3 b"). The second venturi 3b is again typically an axial venturi mixer.

The second venturi 3b generally has at least one portion 30b arranged substantially vertically (generally at the end portion of the second venturi) in view of the conditions of use.

The vertical portion 30b is arranged around the axis a so that the second venturi 3b, adapted to allow the passage of the mixture, defines a space outside the axis a, thus surrounding the axis a.

The second venturi 3b therefore generally has at least one outer wall 31b and one inner wall 32b disposed inside the inner wall. Thus, the second venturi 3b is generally annular or frame-shaped in cross-section.

Thus, there is a second gas inlet 2b on the burner 1 to supply gas to the second venturi 3 b. Similarly, the burner 1 is configured to allow the primary air to enter the second venturi 3b through an air inlet 4b formed on the burner 1 and/or on the cooktop to which the burner 1 is intended to be coupled.

The second venturi 3b can be directly connected to the respective distribution chamber 5', even if embodiments are not excluded in which there is a duct between the second venturi and the respective distribution chamber 5'.

The position of the first venturi 3a and the second venturi 3b, and in particular the position of the first inlet 2a and the second inlet 2b, can be chosen as desired.

For example, in a possible embodiment as shown in fig. 1-4 and 6, the inlets 2a, 2b may be substantially orthogonal to each other.

In a possible variant, such as the embodiment shown in fig. 5, the inlets may be arranged close together, for example at an angle of less than 40 degrees to each other.

According to a possible embodiment of the invention, for example similar to the one shown in fig. 7A and 7B, the first venturi 3a can feed the distribution chambers 5, 5' of two different flame diffusers, so that the second venturi 3B is not present.

In particular, a central annular chamber 73 ("annular" has the previously discussed meaning) may be provided, arranged substantially vertically about the orthogonal axis a. The annular chamber 73 is therefore substantially identical to the vertical portion of the second venturi 3b described in the previous embodiment. Unlike the latter, however, this annular chamber 73 is not connected to its own gas inlet, but is fed by fluid channels 71, 72 similar to those described in the previous embodiments. In particular, the annular chamber 73 is fluidly connected to both fluid passages 71, 72 such that a portion of the mixture passing through these passages is directed to the annular chamber 73.

Typically, a first conduit 73a connects the annular chamber 73 to the first fluid passage 71, and a second, different conduit 73b connects the annular chamber 73 to the second fluid passage. Preferably, the conduits 73a, 73b are not directly connected to each other. In addition, according to a preferred aspect, the ducts 73a, 73b are symmetrical with respect to the same plane of symmetry P of the end openings 71a, 72a of the fluid channels 71, 72.

The mixture leaving the first venturi 3a is then deflected by the compartment 70 and then enters the fluid passages 71, 72. From here, a portion of the mixture is fed to the outer flame diffuser 6a, while a portion of the mixture is fed to the annular chamber 73, and from there on to the flame diffuser 6B (not shown in fig. 7A and 7B, but similar to the flame diffuser 6B shown in fig. 1, for example).

The burner 1 according to the invention (burner with two venturi ducts 3a and 3b of the first embodiment and burner with only one venturi duct 3a of the second embodiment) is also equipped with a housing 8 for a temperature sensor or probe 9.

The housing 8 is arranged at an axis a, i.e. the axis a extends through the housing 8.

According to a preferred aspect, the housing 8 is obtained concentrically with the second venturi 3b, or in any case is surrounded by the second venturi 3 b. In particular, according to a possible aspect, the housing 8 is defined by an inner wall 32B of the portion 30B of the second venturi 3B, or by an annular chamber 73 in an embodiment equipped with a single venturi (for example fig. 7A and 7B).

The housing 8 is arranged substantially parallel, preferably coaxial, to the a-axis.

Preferably, a portion of the housing 8 is located laterally of the first venturi 3 a. In other words, the housing 8 is rather deep, so that a portion of the housing 8 is arranged transversely to the first venturi 3 a. Thus, there is at least one plane orthogonal to the axis a, which plane intersects both the housing 8 and the first venturi 3 a.

In a known manner, the burner 1 also has an ignition device 10, the ignition device 10 comprising, for example, an ignition spark plug and a thermocouple, the ignition device 10 being adapted to allow the burner 1 to be ignited, i.e. to form a flame at the outer flame diffuser 6 a.

From the above description, the use of the burner 1 is clear to the field technician. In short, primary air (shown with small dashes in fig. 5) and gas (shown with large dashes in fig. 5) enter the first venturi 3a to form a mixture (shown with dot-dash lines). The mixture is then directed to one or more fluid passages 71, 72 (e.g., through the compartment 70) to reach the dispensing chamber 5. From here, the mixture flows out of the outer flame diffuser 6a and is ignited by the ignition device 10.

In this embodiment, in the case of the internal flame diffuser 6b, the mixture reaches the annular chamber 73 through ducts 73a, 73b, the ducts 73a, 73b being directly connected to the fluid passages 71 and 72. Next, the second distributor chamber 5' supplies the mixture to the internal flame diffuser 6 b.

Although not shown in fig. 5, in order not to unduly complicate the drawing, if the second venturi 3b is present, gas and air are also injected into the second venturi 3b so as to form a mixture which is conveyed by the second venturi 3b to the distribution chamber 5' flowing through the portion 30b of the second venturi 3 b.