EP0719982B1 - Gas burner for cooking top, cooking range or the like - Google Patents

Abstract

The burner comprises a head attached to a gas inlet, consisting of a base (1) and a cap (2) with a partition (10) between them, forming a first chamber (4) above it to let out the gas to provide the main flame (6), and a second chamber (11) with a peripheral outlet slit (13) for a pilot flame (8). The partition has a central aperture with a dropped rim (17) which slides over the central part of the base and engages with an annular recess (18) in it. The partition and/or base have a series of bosses (20) to ensure the correct size of the slit. The partition also has centering pins (21) for the cap.

Description

The main subject of the present invention is a improved gas burner to equip a table cooker, stove, or the like.

Cooktops or stoves are the most often equipped with several open flame burners.

Each burner generally includes a head connectable to a gas inlet pipe and consisting essentially of two removable parts, know a base covered by a hat for define a room from which the gas at the periphery of the head to provide a so-called main flame, capable of heating a container placed above the burner head.

Many of these burners operate on the principle of the piloted flame. More specifically, a pilot flame is produced under the main flame to ensure good combustion stabilization for all distributed gases, good flexibility in adjusting the power and good ignition of the main flame.

We could refer for example to the document FR-A-2 656 677 which describes a gas burner corresponding to the preamble of claim 1.

However, pilot flame gas burners currently known present a number disadvantages in the pilot flame. In effect, the flow of flame gas supply driver is most often defective due to gas leaks occurring at the interface of the parts stacked forming the burner head. This flow of uncontrolled gas in the supply of the pilot flame therefore has the effect of disturbing the combustion at the level of the main flame which located above the pilot flame.

Specifically, in gas burners currently known, the sealing of the burner head produced by the simple stacking of the parts which constitute it, basically know the base and the cap, is not perfect, and this due to flatness defects which still exist at the contact areas of these two pieces so that it occurs at this location leaks, i.e. a variable gas flow and random on the periphery of the burner. The flame pilot is therefore disturbed and, by way of Consequently, the main flame also.

Also, the object of the present invention is in particular to solve this problem by proposing a gas burner improved in that the flow of gas supplying the pilot flame will always be controlled and will confer so at this flame an optimal regularity and therefore likely to provide good stabilization at the main flame.

To this end, the invention relates to a gas burner perfect for hob, stove or analogous, and of the type comprising a head which is composed a base comprising a central part constituting the entry of the air-gas mixture in the head, from a hat and a spacer interposed between the base and the hat on the one hand define with the hat a first chamber from which gas can escape orifices formed at the periphery of the head between the spacer and the cap, to produce a flame main, and on the other hand define with the base a second bedroom communicating with the first chamber and from which gas can escape through a peripheral slot formed between the free edge of the spacer and the base to give birth to a pilot flame under the main flame, characterized in that said spacer comprises a center opening with dropped edge which is mounted at sliding on the central part of the base and which just fits into the bottom of an annular groove formed in the base around said central part so as to create the peripheral slit producing the pilot flame.

According to another characteristic of this burner, the spacer extends in its plane beyond the edge fallen above to form a crown supported on the central part of the base.

It will also be specified here that the spacer and / or the base are provided with bosses or the like opposite the aforementioned peripheral slot.

The spacer is also provided with centering pins of the hat on said spacer.

It should also be observed here that the base, the spacer and the cap constituting the head of the burner may have a circular shape or else a star shape with at least three branches.

But other features and advantages of the invention will appear better in the description detailed which follows and refers to the attached drawings, given only by way of example, and in which.

Figure 1 is a half view in axial section of a head gas burner according to the prior art.

Figure 2 is an axial sectional view of a burner to gas in accordance with the principles according to this invention.

Figure 3 is an exploded view and partially in section of the burner head shown in the figure 2.

Figure 4 is a half view in axial section of another embodiment of the burner according to this invention.

Figure 5 is a schematic perspective view of another form of burner head using the principles of the invention.

Referring first to Figure 1, we see a known gas burner head which consists of a base 1 closed by a cap 2 and comprising a part control unit 3 in the form of a portion of duct capable of to communicate with an entry (not shown) of the air-gas mixture to supply the defined chamber 4 by the base 1 and the cap 2.

The gas in chamber 4 will exit through orifices 5 formed in the periphery of the cap 2 which has generally a circular shape and this so give birth to an illustrated main flame schematically in 6. Hat 2, below the orifices 5, still has a plurality of other smaller orifices 7 through which the gas will pass for give birth to a pilot flame shown schematically at 8, and this after passing through a baffle 9 formed between the base 1 and the cap 2.

As is always the case in gas burners room 4 is simply the result of stacking of the parts constituted by the cap 2 and base 1, but most often there are faults of flatness P at the level of the zones or surfaces annulars in contact with the cap 2 and the base 1. In effect, the flatness of these areas or surfaces in contact is not sufficient, either because the tolerances of manufacturing do not allow it either because the more or less complex shape of the burner does not allow mechanical surfacing, or even because the deformations due to heat or aging cause flatness defects. So like materialized by the arrow F in Figure 1, it produces parasitic leaks in the areas of parts contact, these leaks adding to the flow of gas leaving through orifices 7 and disturbing by consequently the homogeneity of the pilot flame 8 and, by consequence, that of the main flame 6.

The present invention in particular overcomes these disadvantages in planning, as seen on Figures 2 and 3 a substantially flat spacer and circular 10 interposed between the base 1 and the cap 2.

This spacer 10 defines with the cap 2 a first bedroom, namely bedroom 4, capable of give birth to the main flame 6 as we will describe in detail later.

The spacer 10 also defines with the base 1, of the other side, a second chamber 11 for distributing the gas communicating with the first chamber 4 thanks to a plurality of calibrated orifices 12 formed in said spacer. This chamber 11 will allow a gas flow controlled likely to give rise to flame pilot 8, as will be described in detail later.

A slot 13, through which the gas from the second chamber 11 to produce the pilot flame 8, is created at the periphery of the burner head between the free edge of the spacer 10 and the base 1.

This peripheral slot 13 results from mounting by sliding and interlocking of the spacer 10 on the central part 3 of the base 1 which, as seen well on figure 2, is connected to a system venturi 14 upstream of which is provided a gas 15, so as to supply the chamber 4, and also the chamber 11 via calibrated orifices 12, with a suitable air-gas mixture.

More precisely, and as we can see better on the Figure 3, the spacer 10 has in its center a opening 16 with dropped edge 17.

This fallen edge 17 can be slidably mounted on the central part 3 of the base which has a shape of revolution ensuring the centering of the spacer 10, as can be seen in FIG. 2. In addition, the dropped edge 17 is housed in an annular groove 18 provided in the base 1 and externally concentric with the central part 3. Thus, as we includes, the fallen edge 17 of the central opening 16 in the spacer 10 will come to fit at the bottom of the groove 18, so as to create the peripheral slot 13 producing the pilot flame 8.

Although this is by no means compulsory but nevertheless preferable, the base 1 may include at its periphery, and opposite the spacer 10, a extra thickness 19 on which will be supported bosses or the like 20 provided on the underside of the spacer 10, as seen in Figures 2 and 3.

It is important to observe here that the leaks gas parasites that could theoretically occur between the central part of the base 1 in the form of portion of conduit and the fallen edge 17 are almost nonexistent, or at the very least reduced to this level, due to the very narrow passage and baffle formed by the insertion of the edge 17 of the opening 16 of the spacer 10 in the groove 18 of the base 1 around the central part 3. In any case, such parasitic leak, if it existed, would not certainly not likely to disturb the gas flow, coming from calibrated orifices 12, in the distribution 11, and therefore would certainly not be likely to disturb the pilot flame 8 and therefore the flame main 6.

It will also be observed here that the calibrated orifices 12 have a diameter greater than 2 mm so that allow their realization other than by recovery mechanical.

As it still appears clearly in Figures 2 and 3, the upper face of the spacer 10, facing of cap 2, is provided with pins 21 for centering said hat on said spacer.

As for hat 2, it has on the underside, and as known per se, a crown of slots 22 of so as to form, by pressing on the spacer 10, as much orifices for the passage of the air-gas mixture producing the main flame 6.

It will be observed in this regard that the cap 2 can perfectly, without departing from the scope of the invention, to be whether or not integral with the spacer 10. Also, in this order of ideas, the crown of slots 22 could be provided on the periphery of the upper face of spacer 10, instead of being provided on the underside hat 2 as seen in Figure 3.

The embodiment of the burner illustrated by the Figure 4 differs from that described above, only in that the spacer 10 extends next its plan, and in the direction of opening 16, beyond the fallen edge 17. Thus, the projecting annular part of the spacer 10 will somehow form a crown 23 able to bear on the annular face upper 3a of the central part 3 of the base 1. On therefore understands that in this case, we limit even more the stray gas leakage effect, if any exists, from the first bedroom 4 to the second room 11, and this by the fact that the chicane effect at the fallen edge 17 and the groove 18 is further increased by the presence of contact between the face upper 3a of the central part 3 of the base 1 and the crown 23 of the spacer 10. Since it there will therefore be no parasitic entry of gas into the distribution chamber 11, outside the supply in gas via the calibrated orifices 12, and this all the more more than the contact area of elements 23 and 3a is orthogonal to the arrival of the air-gas mixture by the central part 3 of the base 1, it is permissible to say that if, by impossible, there was a slight overpressure in chamber 11 which could disturb the pilot flame 8, a return of gas in the current gas reaching the burner head, could be carried out as indicated by the arrow G on the figure 4.

In the above description, the base 1, the spacer 10 and the cap 2 constituting the head of burner have a substantially circular shape, but, as we can see in figure 5, we could perfectly apply the invention to a head of three star burner branches 24. This means that each of the above elements constituting the burner head would have the form of a three-pointed star.

It would even be possible to provide a number of branches greater than three.

We therefore produced according to the invention a gas burner whose combustion quality is perfect due to in particular the quality of the stabilizing pilot flame the main flame.

Of course, the invention is by no means limited to described and illustrated embodiments which have not been given as an example.

This is how the shape of the burner head can be other than those described and represented, in depending on the application.

Claims (4)

1. Sophisticated gas burner for cooking top, cooker or similar, of a type including a head composed of a base (1), having a central part (3) that constitutes the entry of the air and gas mixture in the head, a cap (2) and a crosspiece (10) interposed between the base (1) and the cap (2) that on the one hand defines with the head (2) a first chamber (4) from which the gas can escape through orifices formed on the periphery of the head between the crosspiece (10) and the cap (2) in order to produce a principal flame (6), and on the other hand to define with the base (4) a second chamber (11) that communicates with the first chamber (4), and from which the gas may escape from a peripheral slot (13) formed between the free edge of the crosspiece (10) and the base (1) in order to produce a pilot flame (8) under the principal flame (6), characterised by the fact that the said crosspiece (10) includes a central opening (16) with a flanged edge (17) that is mounted with a sliding motion on the central part (3) of the base (1) and that fits together in the bottom of a ring shaped groove (18) put into the base (1) around the said central part (3) in such a way as to create the peripheral slot (13) that produces the pilot flame (8).
2. Gas burner according to claim 1, characterised by the fact that the aforementioned crosspiece (10) continues on its plane beyond the aforementioned edge to form a crown (23) that is built on the central part (3) of the base (1).
3. Gas burner according to claims 1 or 2, characterised by the fact that the crosspiece (10) and / or the base (1) are equipped with bosses or similar (20), opposite the aforementioned peripheral slot (13).
4. Gas burner according to claims 1 to 3, characterised by the fact that the aforementioned crosspiece (10) is provided with centring pins (21) of the cap (2) on the aforementioned crosspiece.

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