EP1120603B1 - Gas burner with multiple flame rings - Google Patents

Abstract

A gas burner with multiple gas rings comprising: a burner body (6) mountable underneath a top plate, with a cut-out section, of an appliance and incorporating a first, upwardly directed gas injector (14) and a second gas injector (9) followed by a horizontal tubular Venturi (10) opening into a vertical well (12); an outer burner head (3) seated on the body (6) through the cut-out section and spaced at a distance above the plate and provided with an annular chamber (22) open above the well (12) and having one or two rows of orifices for flames (4,5); and an inner burner head (1) shaped so as to have a radial divergent (37) coaxially supplied by the first injector through a recess located at the center (31) of the head (3), ports being provided in the head (3) so that all the primary air and the secondary air needed to operate the multiple burner arrives from the top of the top plate of the appliance.

Description

The present invention relates to improvements brought to the sets formed by a plate of above a cooking appliance, especially for use household, and by a gas burner with multiple crowns of flames which is adapted to be mounted on said plate, according to the preamble of claim 1.

Such burners are used when high heating power is required and / or in conjunction with respective feeding devices in central and annular burners, when a modulation of the heating power, in location and in time, is required (Asian cuisine by example).

We already know in particular multiple burners flame crowns with a central burner at one ring of flames and an annular burner provided with a outer flame crown or two crowns of flames, respectively inner and outer.

However, these burners retain structures inappropriate to provide the desired security currently, in particular in prevention against extinguishing the flames, and also with regard to compactness, especially vertical.

The document FR 2 650 369 relates to a gas burner with several concentric heads. However, the layout of this known burner (vertical injectors, venturis defined by vertical parts, etc.) does not lead to optimal compactness that is required for a burner intended to equip a low cooktop thickness.

The object of the invention is therefore to propose a burner multiple flame crown gas of an improved type, whose structure is appropriate to confer a level modern security while still simple to manufacture with a number of component parts reduced to a minimum, and in addition with a relative vertical development reduced allowing its implementation as well on a conventional stove that on a plate of cooking.

For these purposes, a burner as mentioned in preamble, being arranged in accordance with the invention, characterized by the provisions of the characterized in claim 1.

Thanks to the structure adopted, we constitute a burner with multiple crowns of flames in which the all the primary air required for the operation of the first burner, central, and second burner, annular, is brought respectively to the vicinity of the first and second gas injectors by paths located exclusively above the top plate of the camera cooking; for this purpose, the primary air enters the annular space defined between the burner head outside and the top plate, through the recesses lateral support means of the burner head outside and enters the burner body where it is mixed with the gas jet coming out of the first injector feeding the central burner, while otherwise it passes from said annular space directly above, by a lateral opening provided for this purpose, towards the entrance to Convergent-divergent horizontal duct where it is mixed with the gas jet coming out of the second injector for the external burner feed.

Likewise, all of the secondary air that comes feed the flames comes from the top of the plate above ; this secondary air is made up partly by the ambient air surrounding the burners (crown of flames outer ring of the second burner, annular; crown of flames of the first burner, central), or partly by a fraction of the air penetrating into the annular space defined by the outer burner head and the plate of above, this fraction of air passing through aforementioned lights, between the two burners central and annular and feeding the flames of the crown inside the annular burner and, in part, the flames of the central burner.

The multi-crown burner is thus arranged of flame with structural provisions specific to provide an air supply, primary and secondary, leading to the prevention of a repercussion of the uses underlying parts of the cooking appliance on the flames, even at low speed, in other words to prevent a possible extinction of the flames, especially at low during a violent closing of the door of a underlying oven in particular.

In addition, the arrangement of the horizontal Venturi for feeding the external burner head and Venturi directed upwards and constituted, as indicated further, partly tubularly and partly radially horizontally, provides a burner of relatively low height suitable for mounting too well on a stove than on a hob.

In a first possible embodiment, which has the advantage of simplicity, the central well of the inner burner head is directed substantially vertically and the axis of the first injector is substantially vertical.

However, in another embodiment, interesting because it leads to a significant lengthening of the Venturi and therefore to a better efficiency of the air-gas mixture, it is expected that the central well of the burner head inside and the first injector that is substantially coaxial range of approximately 15 to 20 degrees to the vertical.

In an example of a job creation in household cooking appliances, it is expected that the gas burner has a single annular chamber in the outer burner head, which is lined bilaterally by passages of flames, and that the second burner, annular, has two crowns of flames, the burner being of the type with three crowns of flames.

In a structurally simple realization that allows the creation of a small number of be made in a foundry, the means of support of the external burner head are integral with said head external burner and are constituted in the form general of a skirt projecting below the below said head and a surrounding shoulder the central recess of the central region of said head burner. With the same concern, the annular chamber of the external burner head can be closed, top, by a removable annular cover placed on the side walls of the room.

Similarly, it is interesting, so that the first burner, central, equipped with a Venturi of length sufficient, that the central well of the burner head interior has a decreasing section towards from the top, thus forming a first section of Venturi, tubular, and that the upper surface of the head of internal burner surrounding the upper hole of the well central defines, together with a lid removable, the overlying, a radial annular divergent forming a second section of Venturi, radial annular.

In an interesting embodiment in this it allows an easy adaptation of the burner to the requirements commercial sales of cooking appliances, it is possible to make sure that the external burner head is surrounded below by an inclined peripheral skirt down and that said peripheral skirt is formed as a removable piece.

Moreover, in order not to multiply the accessories necessary for burner operation and to reduce so the overall cost of the burner, the burner has a thermocouple for detecting the presence of flames and / or electric ignition member and said thermocouple and / or ignition element are functionally associated with the central burner.

A burner arranged according to the invention presents, thanks to its structure, a great flexibility depending on the type of cooking appliance equip. On the one hand, the outer burner head can, depending on the case, be provided with a single crown of flames arranged either internally or externally or be provided with two crowns of flames indoor and outdoor. On the other hand, the burners central and external may, depending on the case, be connected to a common gas supply control, either be connected each to an individual order gas supply, which allows modulation flexible heating conditions in location and in the weather.

• la figure 1 est une vue d'ensemble, en perspective, d'un brûleur à triple couronne de flammes agencé conformément à l'invention ;
• la figure 2 est une vue en perspective analogue à celle de la figure 1 et montrant le même brûleur dans lequel les deux chapeaux ont été enlevés ;
     la figure 3 est une vue de dessus du brûleur montré à la figure 2 avec les deux chapeaux enlevés ;
• la figure 4 est une vue en perspective du seul corps de brûleur ;
• la figure 5 est une vue schématique du brûleur de la figure 1, en coupe selon la ligne V-V ;
• les figures 6 et 7 sont des vues schématiques de deux variantes de réalisation, respectivement, du brûleur de la figure 1, en coupe selon la ligne VI-VI ; et
• la figure 8 est une vue schématique partielle, en coupe, illustrant une variante de réalisation d'une partie du brûleur conforme à l'invention.

The invention will be better understood on reading the following detailed description of certain embodiments given solely by way of non-limiting examples. In this description, reference is made to the accompanying drawings in which:

• Figure 1 is an overall view, in perspective, of a burner triple flame crown arranged in accordance with the invention;
• Figure 2 is a perspective view similar to that of Figure 1 and showing the same burner in which the two caps were removed;
  Figure 3 is a top view of the burner shown in Figure 2 with the two caps removed;
• Figure 4 is a perspective view of the single burner body;
• Figure 5 is a schematic view of the burner of Figure 1, in section along the line VV;
• Figures 6 and 7 are schematic views of two embodiments, respectively, of the burner of Figure 1, in section along the line VI-VI; and
• Figure 8 is a partial schematic sectional view illustrating an alternative embodiment of a portion of the burner according to the invention.

Referring first to Figure 1, the gas burner of the invention comprises a burner head interior 1, which is in a central position, having a ring of peripheral flames (flames 2) and at least one outer burner head 3, which is annular and remotely surrounds the central burner head 1, possessing at least one ring of flames, inner and / or outside. In the example shown in the set Figures, outer burner head, annular, 3 has two crowns of flame, one inner (flame passages 4) and the outer one (passages of flames 5).

The burner further comprises a burner body 6 partially visible in Figures 1 and 2 and shown separately in FIG. 3. This burner body 6 presents here a relatively elongated shape, substantially in correspondence with the diameter of the burner head outside 3 which overcomes said body.

The burner body 6 is arranged to be fixed, by fixing means 7, under the top plate a cooking appliance, such as a stove, which top plate P is visible on the sectional drawings Figures 5, 6 and 7.

At one end of the burner body 6 is a first gas inlet 8, connectable to a gas supply via control means (no shown) which are preferably his own.

As can be seen in Figure 5, the gas supply 8 is in communication with a gas injector 9 located coaxially facing one end of a conduit 10 first converge, then diverge and form Venturi tubular, which extends substantially over the largest part of the length of the burner body 6, i.e. the diameter of the outer burner head 3. Between the gas injector 9 and the duct 10 is a light 11 primary air intake. At its end terminal, the conduit 10 is in connection with a well substantially vertical 12 bringing the air-gas mixture into annular outer burner head 3.

As seen more easily in Figures 4 and 6, the burner body has a second gas inlet 13 distinct from the first arrival 8 above, and arranged, here on the side of the body 6. The gas inlet 13 is connectable to a gas supply via means of control (not shown) which preferably are his own and are distinct from the power control means of the first gas supply 8.

The gas inlet 13 is in communication with a gas injector 14 which is directed upwards: at the 6, the axis of the injector 14 is substantially vertical and substantially coaxial with the burner heads inside 1 and outside 3.

As best seen in Figure 4, the body of burner 5 supports necessary accessories to safe operation of the burner, and in particular at least a thermocouple Th and at least one ignition member electric Aℓ.

The outer burner head 3 rests, through a cutout 30 made in the top plate P, on the burner body 6 via means of support. For this purpose, we can predict, as we see better in FIGS. 4 and 6, that the burner body 6 has a support flange 16 globally circular centrally located and coaxially to the vertical injector 14. This flange 16 forms with the central bottom of the burner body 6 a kind of tank, having the injector 14 in its center and the means of support of the external burner head arranged laterally. In the example illustrated, the means of support are secured to the underside of the burner head 3 and are constituted in the form of a skirt 17 protruding downward by forming an outwardly peripheral shoulder 18 bearing on the top of the collar 16 above. This skirt 17 is made either of continuous way with lights, so discontinuous (as illustrated in Figure 6) in order to constitute passages 20 for primary air like this will appear later.

Note further that the lower edge of the skirt 17 is shaped to cooperate with projections 19 provided in the bottom of the tank, so as to block in rotating the outer burner head 3 on the body of burner 6 and to serve simultaneously to position them mutually angularly correct.

As can be seen in Figures 4 and 5, the part of the outer burner head 3 surrounding the central region provided with the projecting skirt 17 overlooks the top plate P being held at a distance above of it, so that the top plate P and the face bottom of the burner head 3 define between them an annular space 21, of irregular shape with respect to the general conformation of the burner. The passages 20 above communicate with this space 21.

The outer burner head 3 has a annular chamber 22 located in the vicinity of the periphery external of this head. The chamber 22 is formed by a channel defined by a bottom 23 and two side walls concentric 24, 25 and by a lid or hat ring 26 capping said channel. In at least one of 24, 25 are formed notches forming passages of flames. In the example shown, both walls 24, 25 are provided with respective notches 4, 5, so that the outer burner head has a double crown of flames.

The whole of this arrangement is also well visible in Figures 2 and 3.

As shown in FIGS. 2 and 6, the bottom 23 has an opening 27 opposite the well substantially vertical 11 above.

As can be seen in FIGS. 1, 2 and 6 in particular, the annular cap 26 is guided, when it is put in place, and retained in position by positioning fingers 28 secured to the outer burner head 3.

As shown in Figures 3 and 5, the head of external burner 3 is arranged so that between a central region which will be discussed later and the annular chamber 22, it has lights 29 which open this intermediate annular zone, for the purpose to allow a circulation of air as it will appear further.

Finally, the central region 31 of the burner head outside 3 has a substantially vertical recess 32, coaxial with the axis of the injector 14.

The central burner head 1 is supported peripherally on an annular shoulder 33 practiced in the outer burner head 3. Its central region, protruding downwards, is engaged in the recess 32 mentioned above of the external burner head and presents a central well 34 coaxial with the axis of the injector 14. The well 34 has a decreasing section upwards and forms a converge.

The peripheral wall 35 of the burner head central 1 is pierced with indentations 2 forming passages of flames. A cap or cover 36 rests on the wall 35.

The facing faces of the cover 36 and the central region of the central burner head 1 which surrounds the hole in well 34 deviate substantially from one another radially outward, forming a divergent annular radial 37. The whole converge tubular 34 and the radial annular divergent 37 constitutes a Venturi.

In Figure 7 is shown a variant of embodiment of the arrangement shown in FIG. which the central well 34 and the injector 14, coaxial, are no longer vertical but inclined at an angle of 15 to 20 ° from the vertical. This arrangement is preferred vertical axis assembly of Figure 6, due to the elongation provided for well 34: although low, this elongation is sufficient to improve the performance of the burner central 1.

Finally, note that the external burner head 3 is, as is often the case for burners with gas, bottom lined by an annular skirt device 38 inclined downward. This skirt can be integral part of the burner head 3 as visible particularly in Figures 5, 6 and 7, or may be a annular piece 39 removably attached to the head of burner 3: this annular piece 39 can be set place with appropriate shoulders as shown, in partial sectional representation, in FIG. In addition, it becomes easy to conform and / or decorate this annular piece of diverse way to satisfy for example, business requirements.

The structural arrangements that have just been described lead to a multiple gas burner wreaths of flames in which all of the air, primary and secondary, necessary for its operation it is provided by the top of the top plate P, this which avoids the disadvantages (possibility of blowing flames) inherent to partial or total primary air from below the P-plate.

In the figures in section 5, 6 and 7, there is shown schematized by the full arrows F the path followed by the primary air which, since the annular space 21, reaches at the entrance of the duct 10 (FIG. 5) and simultaneously, through the openings 20, reaches the level of the injector 14 (Figures 6 and 7).

As for the secondary air that must reach the feet of the flames, its paths are shown schematically by the arrows in dashes f. It comes partly from the outside of the burner (arrows f ₁ ) for the ring of external flames, and a fraction of the air coming from the annular space 21 and going up through the lights 29 (arrows f ₂ ) and outside air coming from above (arrows f ₃ ) for the two rings of internal flames vis-à-vis.

Finally, note that to simplify the structure of the burner and reduce its cost, only one thermocouple Th and / or a single electrical ignition member Aℓ which are then associated operation only burner central.

Claims (9)

1. An assembly constituted with a top plate (P) of a cooking appliance, in particular for domestic use, and with a gas burner with multiple gas rings designed to be mounted on said top plate, which burner comprises a first, central burner having a ring for peripheral flames and at least a second, annular burner surrounding the central burner at a distance therefrom, having a least one flame ring, said burner comprising:

   a burner body (6) designed to be fixed to the top plate (P), on the bottom thereof, and comprising:

   a first gas inlet (13) and, communicating therewith, a first gas injector (14), the axis of which is upwardly directed,

   a second gas inlet (8) and, communicating therewith, a second gas injector (9) disposed facing a convergent-divergent pipe (10) forming a Venturi;

   an outer burner head (3) supported, by support means (17, 18) inserted in a cut-out section (30) of said top plate (P), by said burner body, said burner head (3) comprising:

   a chamber (22) provided with passages for flames (4; 5) at least around one side and having an opening (27) in its base (23),

   a central region (31) having a central, vertical recess (32), and

   ports (29) disposed between said chamber (22) and said central region (31),

   said support means (17, 18) for the outer burner head (3) being designed so that said burner head (3) is disposed above and at a distance from the top plate (P), forming in conjunction therewith an annular space (21) surrounding said central region, said support means (17, 18) having lateral recesses (29) providing a communication between said central recess (32) of the central region and said annular space (21);

   an inner burner head (1) designed to be centrally supported by said outer burner head (3) facing said central recess (32) of the central region (31), said inner burner head (1) having a central well (34) coaxially aligned with the axis of said first gas injector (14),

   characterized in that the second gas injector (9) has a substantially horizontal axis and the convergent-divergent pipe (10) forming a Venturi extends across at least the greater part of the transverse extension of the burner body (6), said pipe (10) communicating, at its end opposite the second injector (9), with a substantially vertical well (12) open at the top, and in that the chamber (22) is substantially annular and the opening (27) provided in its base (23) is disposed facing said substantially vertical well (12) of the burner body, whereby it is provided a multiple ring burner wherein all the primary air (F) needed to operate the first, central burner and the second, annular burner is delivered respectively to the first and second gas injectors exclusively from above the top plate (P) whilst the secondary air (8) needed for the multiple gas rings is also delivered to the base of the flames exclusively from above the top plate (P).
2. Gas burner as claimed in claim 1, characterised in that the central well (34) of the inner burner head (1) is directed substantially vertically and in that the axis of the first injector (14) is substantially vertical.
3. Gas burner as claimed in claim 1, characterised in that the central well (34) of the inner gas burner and the first injector (14) substantially coaxial therewith are inclined at approximately 15 to 20° relative to the vertical.
4. Gas burner as claimed in any one of the preceding claims, characterised in that it has a single annular chamber (22) in the outer burner head (3) which is provided bilaterally with passages for flames (4, 5) and in that the second, annular burner has two gas rings, the burner being of the type with three gas rings.
5. Gas burner as claimed in any one of the preceding claims, characterised in that the support means (17, 18) of the outer burner head are integral with said outer burner head (3) and are provided in the general form of a skirt (17) projecting down below the bottom of said head (3) and a shoulder (18) surrounding the central recess (32) of the central region of said burner head (3).
6. Gas burner as claimed in any one of the preceding claims, characterised in that the annular chamber (22) of the outer burner head (3) is closed at the top by a removable annular cover (26) placed on the lateral walls (24, 25) of the chamber (22).
7. Gas burner as claimed in any one of the preceding claims, characterised in that the central well (34) of the inner burner head (1) has a section decreasing in the upward direction, thereby forming a first, tubular Venturi section, and in that the upper surface of the inner burner head surrounding the top orifice of the central well (34) defines, in conjunction with a removable cover (36) surmounting it, a radial, annular divergent (37) forming a second, radial annular Venturi section.
8. Gas burner as claimed in any one of the preceding claims, characterised in that the outer burner head (3) is surrounded at the bottom by a downwardly inclined, peripheral skirt (38) and in that said peripheral skirt is provided as a removable part (39).
9. Gas burner as claimed in any one of the preceding claims, characterised in that it has a thermocouple (Th) for detecting the presence of flames and/or an electric ignition member (Al) and in that said thermocouple and/or said ignition member co-operate with the central burner.

Images