ES1214916U - Sequential adjustment system for household cooking tops equipped with multiple injector burners - Google Patents

Abstract

The object of the present invention is a special atmospheric burner (1) comprising a plurality of contiguous flame generation zones (FLn), a plurality of ejectors (EJ.n) adapted to the mixing of combustion air and fuel gas that serve said plurality of flame generation zones (FLn) and a plurality of injectors (INJ.n), each injector (INJ.n) placed at the inlet of the corresponding ejector (EJ.n), for the supply of said fuel gas in said ejectors (EJ.n). Said plurality of injectors (INJ.n), each adapted to serve a specific and dedicated flame generation zone (FLn) of said special burner (1) are fed in series from a single supply line (4) of said fuel gas and are activated by means of at least one control line (3; 3.1... 3.n) connected to a push-button panel (2; 20.n) comprising at least one button (20. n) capable of being pressed according to a specific sequence and/or ignition mode of said flame generation zones (FLn) of said special burner (1). Of said plurality of contiguous flame generation zones (FLn) there are identified a main flame zone (FL1), fed first, equipped with an igniter device (IGN) and a relevant flame detector (FD) and further one or more flame generation zones (FLn) feedable and activatable in sequence one after the other. Each pair of flame generation zones (FLn), including the main one (FL1), fed in sequence, are adjacent to each other in such a manner that, after the activation of said main flame zone (FL1), none may be powered and activated without there being at least one contiguous flame generation zone (FLn) already ignited.

Description

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DESCRIPTION

Sequential adjustment system for domestic gas countertops equipped with a plurality of burners with injector.

The present invention relates to a power adjustment system intended for atmospheric gas burners comprising a plurality of injectors for countertops, in particular for domestic countertops.

Atmospheric burner means a burner in which the air-gas mixture is obtained by the effect of the pressure of the gas supply that uses the principle of the Venturi ejector tube and without the help of fans.

Ejectors are extremely simple, economical and reliable devices and, for this reason, are used to mix fuel gas and air in countertop burners. Substantially, all domestic gas countertops currently on the market use atmospheric burners.

In the Venturi ejector tube (hereinafter referred to as "ejector"), the pressure energy of a motor fluid available in the nozzle disposed at the entrance of a Venturi tube is transformed into kinetic energy; the high-speed jet that exits the nozzle induces and draws a flow of induced fluid at a lower pressure; both flows are conducted inside the Venturi slot in which part of the pressure is mixed and recovered; then the mixing continues in a divergence section (which is the Venturi diffuser) in which the additional kinetic energy is recovered in the form of a static pressure. At the outlet of the diffuser, the combustible gas and combustion air are substantially completely mixed.

The most widespread, more traditional and universally accepted technical solution for the realization of a gas burner of a countertop is the one that contemplates the "vertical Venturi" (hereinafter identified with the abbreviation STD); however, in recent years alternative solutions have been developed to that of the STD, in particular burners comprising a horizontal Venturi or of a "linear" configuration, which is referred to herein as "LIN".

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Said configuration comprises a Venturi with a completely linear development arranged horizontally and parallel to the countertop (on the contrary, in the STD burners the STD diffuser is radial). The linear diffuser leads to an additional mixing chamber that occupies the internal volume of the burner in which the production of the primary air and the combustible gas continues to be produced. Figure 2c represents a comparison between the two types in section.

The thermal power setting of the LIN burner or the STD is generally carried out by means of a manual rotary valve designed to adjust the flow rate of the combustible gas (hereinafter simply referred to as the "adjustment valve") arranged upstream of the Venturi ejector; By continuously reducing the supply pressure to the ejector without steps, a continuous adjustment without steps of said thermal power is obtained between a minimum power and 100% of the nominal power.

Each adjustment valve of each of the burners is keyed and sealed, as is known, in the "ramp tube" (also called "collector") of the gas supply circuit of a countertop, and generally also has a valve safety, connected directly to the thermocouple (flame sensor) that keeps it in the open position when the flame is on and returns to its "normally closed" position when it goes out (see Figure 1).

In ignition of the burner, an external mechanical action (usually the pressure prior to the rotation of the burner control knob) forces the safety valve to switch from its "normally closed" position to the open position.

While the linear displacement safety valves have special sealing elements (seals), the adjustment valves ("taps") are shutter valves whose tightness is guaranteed by the presence of lubricating grease in the gap between the rotating interior and the seat, said elements being generally made by stripping bare brass or aluminum chips; They are not suitable to serve as a safety device.

It has been known for years that there are burners equipped with more than one ejector (also called "special burners" or "poly-injectors") that separately feed more than one "flame generation zone" (hereinafter referred to as,

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for the convenience of the description, "flame zone"), for example, a plurality of concentric flame crowns.

Such "special burners" are actually multiple burners that comprise "n" injectors (usually n = 2 or 3, more rarely 4) that frequently comprise so many "special valves" that they can feed separately or simultaneously, in a continuous or continuous manner. discontinuous, all injectors of an individual burner.

Each crown of flame of the special burner generally requires a dedicated gas supply line that goes from the corresponding special valve to the injector and, at least in some cases, from a corresponding lighter (and associated flame sensor) with clear drawbacks in with regard to structural complexity and global dimensions.

Even the adjustment of the thermal power of these special burners is complex and delicate.

It can be assumed, for example, to have to manage an STD multi-burner comprising two concentric crowns of flames (a centripetal interior and a centrifugal exterior), each fed separately by its own Venturi ejector and adjusted by an individual special adjustment valve that the user can operate by means of a control knob: when the control knob is turned from the OFF position, the innermost crown is enabled and its thermal power is adjusted continuously without stepping from its maximum ( that is, the crown burns at full power) to its minimum, when a small unstable angular sector is reached, followed by an enabling of the outer crown and the concomitant shutdown of the first. Continuing to turn the knob, a progressive reduction in the thermal power of the outer crown is observed until a second unstable angular sector is reached; insisting with the rotation the two concentric flame crowns are enabled simultaneously with the possibility of continuous adjustment without staggering from 100% of the nominal power to 0%.

The modulation curve resulting from said typical management of a special burner is, in portions, continuous and strongly non-linear, as can be clearly seen in the figure

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3a, in which the abscissa represents the angle of rotation of the control of the special valve, while the ordinates indicate the corresponding thermal power of the burner; the three operating areas of the special burner should be noted.

Such power modulability can be overabundant compared to practical needs, being sufficient, as well as in electric countertops, a discrete adjustment with a sufficient number of "increments" (see Figure 3b), while its implementation may result, particularly for less experienced users, not intuitive and not always easy and immediate to understand.

For these burners, it is also intended to increase safety against fuel gas leaks that occur in the event of accidental and sudden extinguishing of the flame or its malfunction.

Patents US 3,694,137 and / or FR.2,800,848 represent burners comprising a plurality of injectors that separately feed more than one "flame generation zone", and although they can be used in sectors other than those of said treated, in particular in the field of space heating and hot water production boilers. The burners described therein are not suitable for use in the field of countertops due to their structural and constructive complexity and / or for their operation and management mode.

The main objective of the present invention is to provide a "special" atmospheric burner suitable for use in countertops, in particular domestic, which eliminates, at least partially, the above-mentioned drawbacks.

More particularly, the main objective of the present invention is to provide a sequential adjustment system of the thermal power of a "special" domestic burner comprising a plurality of injectors adapted to increase the security against the involuntary access of the combustible gas to the burner.

Another objective of the present invention is to provide a simplification and reduction of the overall dimensions of the supply and control line of the burners of a countertop, preferably "special burners".

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Another objective of the present invention is to achieve the above objectives by means of innovative pneumatic or electronic or electromechanical controls.

Another objective of the present invention is to control and manage the ignition of the plurality of flame zones of the special burner by means of a single lighter and flame sensor.

Other features and advantages of the present invention will be better explained by the following description of an atmospheric countertop burner according to the main claims, articulated in possible variants according to the dependent claims and which are represented, by a non-limiting example, with the help of Tables of the attached drawings, in which:

- Figure 1 schematically represents a conventional physical arrangement of a countertop and a safety valve according to the prior art.

- Figure 2a represents, in a graphic legend, arrows that symbolize the air-gas mixtures of different titles and the inlet flow used as an example, with no intention of providing quantitative data, in other figures;

- Figures 2b and 2c schematically represent, respectively, a typical Venturi ejector according to the prior art for an atmospheric burner and a comparison between a burner comprising a horizontal Venturi configuration and a burner comprising a vertical Venturi configuration;

- Figures 3a and 3b represent, respectively, the modulation curves of the thermal power of a conventional burner and of a "special burner" according to the present invention;

- Figures 4a, 4b, 4c, 4d, 4e, 4f and 4g schematically represent a "special burner" and the relevant power and control system according to the different variants of the present invention;

- Figure 5 represents the view of ignition and modulation of the thermal power of the "special burner" of Figure 4a;

- Figure 6 represents an ignition and modulation view of the thermal power of the "special burner" of Figure 4c;

- Figure 7 represents the view of ignition and modulation of the thermal power of the "special burner" of Figure 4d;

- Figures 8.1-8.4 represent, in multiple views in section, an element of the "special burner" control line of the present invention;

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Figures 9.1 and 9.2 represent, in a sectional view and according to a possible variant, a power button and modulation of the thermal power of the "special burner" of the present invention;

Figure 10 represents a countertop that contemplates a plurality of "special burners" according to a first variant of the present invention;

Figure 11 represents a countertop that contemplates a plurality of "special burners" according to a second variant of the present invention;

Figure 12 depicts a countertop that contemplates a plurality of "special burners" according to another variant of the present invention;

Figure 13 depicts a countertop that contemplates a plurality of "special burners" according to another variant of the present invention;

Figure 14 represents a countertop that contemplates a plurality of "special burners" according to a last variant of the present invention.

The following references are described in Figure 1:

 301

 RAMP TUBE 342 CUP 230 GRILLE

 312

 ADJUSTMENT VALVE 212 BODY (RADIAL VENTURI) 120 CONTROL CONTROLS

 332

 GAS PIPES 217 DISTRIBUTED FROM THE FLAME (LOOSE) 147 LIGHTING CONTROL UNIT

 320

 INJECTOR 220 CAP 160 LIGHTER

 303

 GAS 100 GASKET INTAKE BOARD

Unless otherwise specified, any possible spatial reference in this report such as the terms vertical / horizontal or lower / upper refers to the position in which the elements are arranged in the attached figures, while spatial terms such as prior / next, upstream / downstream, should be understood with reference to the direction of circulation of the membrane flow.

In Fig. 2a, some arrows are drawn, each symbolizing a mixture flow of a different speed and title. These arrows are used in many of the figures

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following to exemplify, without any intention of providing quantitative indications, the substantial state of the air, gas and mixture thereof at different points upstream, downstream and inside the burners represented.

In order to highlight some features instead of others, not necessarily what is described in the attached drawings is perfectly to scale.

Also, the figures represent only the substantial elements for the purposes of the present invention.

In the attached figures (see, for example, figure 4a) of the domestic atmospheric burner 1 of the present invention are shown: the cup 14 which defines in its interior the fuel air-gas mixing chamber, a plurality "n" of zones of adjacent flame generation FLn, each one served by its own ejector "Venturi" EJ.n adapted to the mixture mentioned above and at the entrance of the same, the corresponding INJ.n injectors for the supply of fuel gas are positioned.

Each ejector "Venturi" EJ.n comprises, as is known (see for example Figure 2b), a first convergence section 10 (or simply the "convergent") in which the fuel gas pressure energy available in the injector INJ.n is transformed into kinetic energy and in which a flow of combustion air is carried by said high-speed jet of combustible gas; a slot 11 in which the combustible gas and combustion air are mixed recovering part of the pressure energy; a final divergence section 12 (also called "diffuser 12" Venturi) continuing said mixing along it and in which an additional kinetic energy is recovered in the form of static pressure.

Although in the attached figures the ejectors EJ.n are represented of the STD type (that is, as already anticipated, they comprise a "vertical Venturi") nothing prevents them, for the purposes of the present invention, from being of the type LIN, which comprises a "horizontal Venturi", or in any case arranged around the burner body.

Likewise, although it is not explicitly represented, the flame zones FLn fed by said ejectors EJ.n can comprise, without distinction, a plurality of concentric crowns of flames or present other shapes as long as they are contiguous, each of

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them to all of the following (for example, without any attempt at limitation, four concentric crowns or contiguous "slot groups" FL1, FL2, FL3, FL4).

At least in a flame zone FLn, hereinafter referred to as the main FL1, a known ignition device IGN (also called "lighter IGN") is provided, for example of the piezoelectric type.

These contiguous FLn flame zones are adjacent to each other, so that none (except, as will be noted, the main FL1) can be fed and activated by its own dedicated ejector EJ.n without at least one flame zone already existing. adjacent FLn on.

In this way, the pilot flame functionality that keeps the flame on and systematically propagates it to all slots of a traditional STD and / or LIN burner is proposed again.

Ensuring the continuity of the FLn flame zones also avoids the need to use a plurality of FD flame sensors, one for each FLn flame zone.

For the special burner 1 of the present invention, therefore, only a flame sensor FD is provided in the flame zone FL1, herein referred to as "main", already equipped, as noted, with the IGN lighter .

For the sake of simplicity of the description, said flame sensor will hereafter referred to as "FD flame detector".

The thermal power of a special burner 1 of these characteristics (also called "poly-injector burner 1") is exclusively a function of the number of flame zones FLn active simultaneously.

In other words, the burner 1 operates at the minimum power Pmin when only the main flame zone FL1 is activated, while reaching its maximum power Pmax when all its flame zones FLn are simultaneously enabled.

It is clear that, in the event that all EJ.n ejectors are identical to each other, the

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Modulation ratio Y of the special burner 1 (equal, as is known, to the ratio between its maximum and minimum power) will be equal to the total number of flame zones FLn. Obviously, for the purposes of the present invention, nothing prevents providing ejectors EJ.n even different from each other.

The reference number 2 also denotes a panel of push buttons, comprising at least one button 20.n intended for the activation of said special burner 1 and for its modulation as regards the power.

As will be seen, said push button panel 2 can be of the electromechanical, or electronic or pneumatic type and is connected to the injectors INJ.n of the special burner 1 by at least one control line 3, 3.n.

More particularly, according to the present invention, an individual control line 3 adapted to service all the injectors INJ.n of the burner 1 (see Figures 4c, 4d, 4e, 4f) or, alternatively, so many control lines can be provided 3, 3.1 ... 3.n dedicated as said INJ.n injectors (that is, one for each INJ.n injector) as shown in Figure 4a or 4b.

Said at least one control line 3.n can be connected directly to at least one button 20.n of said push button panel 2 or, according to some variants (of the electrical type), to an electrical control circuit CMD which can receive specific control signals from the same push button panel 2 (said CMD circuit being able, as will be observed, also receive signals from the FD flame detector and send second signals to the IGN lighter and to a burner valve 1, to the which will be called "security SV").

Hereinafter, the push button panel 2 and the at least one control line 3 of injectors INJ.n will be called the "control system" of the burner 1.

The different types of architectures of said control system 2 will be briefly named with the description of some of the preferred and functional embodiments thereof.

While said push button panel 2 is shown in the attached figures of the type

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comprising at least one mechanical push button, nothing prevents providing, without any exhaustive attempt, rotary or linear potentiometers or any other type of control known to the manufacturers and designers of countertops.

Also, according to the present invention, an individual gas supply line 4 (also referred to as "adduction line 4") serves the entire plurality of injectors INJ.n of the special burner 1, arranged in series with each other.

Said supply line 4 is disconnected by a known and conventional safety valve SV against gas leaks produced in the event of accidental and sudden shutdown of the flame or malfunction of the burner 1.

As clearly shown in the accompanying figures, said safety valve SV is disposed upstream of the plurality of injectors INJ.n of the special burner 1.

Even if it is well known to the person skilled in the art, it is useful to specify that said safety valve SV (eg an electric actuator) is piloted by the push button panel 2 of the burner 1 to switch from a configuration of "normally closed" to one of "open", suitable for the passage of combustible gas, and which is maintained as such while the flame detector FD mentioned above detects at least one zone of active flame FLn. The absence of such a signal will, on the contrary, determine the closure of said safety valve SV and the subsequent disconnection of the supply line 4, thereby interrupting the supply of combustible gas to the special burner 1.

Suitable and known wiring 50, 51 respectively connect the safety valve SV and the flame detector FD to the push button panel 2 while a cable 52 controls the ignition of the IGN lighter.

According to another important aspect of the present invention, each injector INJ.n of the burner 1 is equipped with a special sealing device 6 (see in particular Figure 8), "normally closed", although it can allow or prevent, when operated, the outlet of the gases towards the corresponding ejector EJ.n for the activation of the associated flame zone FLn, although at the same time it ensures its passage to the next INJ.n injector (with respect to the direction of gas travel along only a line of

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4) supply.

Said shutters 6 are interlocked with the flame detector FD.

Although in the figures attached herein, said sealing device 6 and injector INJ.n are represented as strongly integrated with each other to form a single valve body, nothing prevents them from being also physically and logically separated elements.

According to the present invention, each INJ.n injector, in addition to feeding the corresponding EJ.n ejector, also acts as a gas shut-off valve that provides additional security against gas leakage to the external environment of the home with the burner 1 turned off. or in the case of accidental flame shutdown. As already anticipated, the linear shutters in the closed position ensure an intrinsically better seal of the corresponding conventional adjustment taps.

Even in the event of failure of the safety valve SV, inadvertent or unwanted access of gas to the burner 1 is prevented by the presence of the shutter device 6, normally closed, on board each injector INJ.n.

The electromechanical or pneumatic actuators 7 guide the switching of the sealing device 6 from its natural configuration of the injector INJ.n from closed to that of open and vice versa.

Without any intention of completeness, the suitable electric actuators 7 can be of the type (in the attached figures shown only schematically) comprising a coil substantially wound around the sealing device 6 and can convert the electrical signal generated and transmitted thereto by the push button panel 2 by means of the at least one control line 3 mentioned above (in this case, therefore, of the electric type), in an electromagnetic field that causes a linear displacement thereof.

Obviously, nothing prevents the possibility of providing, alternatively, pneumatic actuators 7 that use pressurized or pressureless air as an energy conveyor and can displace said sealing device 6 by means of a pressure (or

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reality, as will be observed, the vacuum) generated by acting on at least one button 20.n of the push button panel 2 which, therefore, behaves like an authentic volumetric pump.

In both cases, as will be observed, the presence of a stationary spring element of said actuator 7 allows, when the electric or pneumatic impulse generated through the push button panel 2 ceases, the return of the sealing device 6 to its rest position coinciding with that of "normally closed".

In the description, reference will be made to the possible configurations of said actuators 7 and sealing device 6 of each injector INJ.n.

The essence of the present invention has already been described, constituting a special burner 1 comprising a plurality of injectors INJ.n:

- fed in series from a single fuel gas supply line 4

- each of them adapted to service a specific and dedicated FLn flame area of the special burner 1

- their activation, necessary to allow the sequential ignition of said flame zones FLn and a modulation of the thermal power of said same special burner 1, is assigned at least to a control line 3 connected to a push button panel 2 which It comprises at least one button 20.n which can be pressed according to an ignition sequence and / or suitable and specific mode.

The special burner 1 of the present invention also incorporates a double level (or system) of safety against gas leakage in the case of incomplete ignition of the same or accidental shutdown of the flame secured, on the one hand, by the valve of safety SV arranged along said fuel gas supply line 4 upstream of said same plurality of injectors INJ.n, and, on the other hand, for each of the same injectors INJ.n which, by means of their respective sealing devices 6 , act, as noted, as shut-off gate valves, said safety valve SV and shutter devices 6 being able to close instantly (or remain closed) in the absence of a flame signal detected by at least one FD flame detector of the special burner 1.

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At this point, the typical ignition sequence of a special burner 1 will be described as described above.

When the special burner 1 is lit (by pressing the relevant ignition button), when acting on the push button panel 2, the safety valve SV "normally closed" of the fuel gas supply line 4 is forced to open, The shutter device 6 of the first INJ.1 injector is retracted, opening the gas access to the corresponding ejector EJ.1, and the IGN lighter for ignition of the flame in the main flame zone FL1 is activated.

Once combustion starts in the main flame zone FL1, the flame detector FD creates an electrical voltage (which, as is known, is a function of the local temperature reached) that maintains both the safety valve SV and the injector INJ .1 in the open position.

Therefore, the main flame zone FL1 remains lit and the special burner 1, as anticipated, is at its minimum thermal power.

Conversely, if the user stops the ignition procedure before the flame has stabilized, the absence of a flame signal detected by the aforementioned FD detector causes the simultaneous and instantaneous closure of the safety valve SV and the INJ injector. 1, double inhibiting the passage of gas to the burner 1.

The adjustment of the thermal power level of the special burner 1 of the present invention goes through the successive and incremental enablement of the other ejectors EJ. through the opening of the sealing devices 6 of the corresponding INJ.n injectors and in such a way that each pair of FLn flame zones fed consecutively are adjacent to each other (see the "increments" modulation curve in Figure 3b).

Although it has already been mentioned above, that is, said modulation of the thermal power of the special burner 1 is subjected to the contiguity of its flame zones FLn, meaning that a flame zone FLn cannot be fed and activated by its own dedicated ejector EJ.n without having at least one adjacent flame zone already lit; that is, the flame zone FL2 can only be enabled after activation of the adjacent main flame zone FL1, and so on for flame zones FL3,

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Fl_4 following the special burner 1.

Similar considerations are also valid in the case of a reduction in the thermal power of the burner 1, that is, in the case that it is necessary to proceed with the sequential and progressive shutdown of one or more of its FLn flame zones.

Therefore, summarizing what has been described up to this point, of the special burner 1, have been identified:

- a FL1 main flame zone equipped with IGN lighter and relevant flame detector FD and fed by at least one corresponding INJ.1 injector

- others one or more FLn flame zones, each of them fed by at least one respective INJ.n injector.

in which:

- said main flame zone FL1 is fed first

- said one or more additional flame zones FLn are fed and activated sequentially one after the previous one

- each pair of FLn flame zones, including the main one, that are fed sequentially are adjacent to each other.

Figure 4a represents in greater detail a first version of the control system of the special burner 1.

Said control system provides an electromechanical push button panel 2 comprising a number of push buttons 20.n 20.1 ... 20.4 equal to that of the activatable flame zones FLn in which said number of zones is less than or equal to the number of INJ.n injectors of the special burner 1.

More particularly, each push button 20.n is connected via an own control line 3, 3.1 ... 3.4 to the corresponding INJ.n injector or to as many groups of IJN.n injectors, therefore, as many control lines 3 are provided as of flame zones; each of them is equipped with at least one INJ.n injector of the special burner to be managed.

Therefore, each button 20.n of the push button panel 2 can enable the zone

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of corresponding FLn flame according to the sequence described above in general terms, simply using the known switching means for the electrical signals.

At least one of said push buttons 20.n of the push button panel 2 is also connected to the corresponding INJ.n injector (or, as will be understood, to the corresponding INJ.n "injector group), as anticipated, also to the igniter IGN and flame detector FD of the special burner 1 and to the safety valve SV of the gas supply line 4.

Said button 20.n is 20.1, adapted to enable the main flame zone FLi of the burner 1, in which said zone FL1 is the one that is expected to light first.

Therefore, a press of it will give the opening order of said safety valve SV and of at least one main injector INJ.1 and the simultaneous activation of the IGN lighter that can "ignite" (by means of the known spark produced in this way) the intended air-fuel mixture for said main flame zone FL1.

Once the ignition of the burner has occurred and has stabilized, repeated and sequential pressing of the other push buttons 20.n of the push button panel 2 will cause the progressive activation of the adjacent FLn flame zones and the consequent increase in the thermal power of the same burner 1.

On the contrary, the shutdown of a previously activated flame zone FLn and the corresponding reduction in the power of the burner 1 is achieved by pressing any ignition button 20.n of a flame area FLn not immediately adjacent to the one to be deactivated.

For example, the shutdown of the second FL flame zone of the special burner 1 (previously activated by button 20.2) will be achieved by pressing button 20.4 dedicated to enabling the fourth and last FL4 flame zone (see the position of the representation of a user "hand" at point (iv) of figure 5).

The pre-operation logic represents just one example of the countless possibilities offered by the proposed adjustment system and can be safely implemented with common electromechanical devices already available to a person skilled in the art.

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Even for the electronic variant of Figure 4b, each injector 12.n is controlled by a special and dedicated control line 3; 3.1 ... 3.4 ... 3.n.

However, according to the present constructive variant, said control lines 3.n are connected directly to an electrical control circuit CMD which can:

- receive signals from the push button panel 2 and the flame detector FD via cables 53, 51, respectively

- send control signals to the IGN lighter and the safety valve SV of the fuel gas supply line 4 to the burner 1 via the wiring 52, 50.

More particularly, according to said variant, the push button panel 2 may comprise a pair of buttons 20.n symbolically represented in Figure 4b by a first key (+) 20.1 and by a second key (-) 20.2 connected to said circuit of CMD electrical control; with a first press of the (+) 20.1 key, therefore, the activation of the main flame zone FL1 will occur while each subsequent press will cause the activation of contiguous areas until the desired thermal power for the special burner has been reached one.

It will be called CMD electrical control circuit to recognize if the pulse exerted on said button (+) 20.1 corresponds to that for the first ignition of the special burner 1 or to which it is to increase its power depending on whether it is received or not the flame signal from the flame detector FD.

On the contrary, with each press of the (-) key 20.2 the CMD electrical control circuit will manage the sequential shutdown of the FLn flame zones already activated until the minimum thermal power of the burner 1 or its final shutdown has been reached.

In the ignition and power modulation versions of a special burner 1 mentioned above there is, as has been observed, always a single one-to-one connection between each button 20.n of the push button panel 2 and the shutter device 6 of each INJ.n injector: as observed, in effect, each button 20.n of the push button panel 2 is connected to the corresponding INJ.n injector through individual and separate control lines 3.n.

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This makes the assembly of a plurality of special burners 1 on a countertop rather complex and expensive.

Therefore, in order to solve this problem, a simplified variant of the control system of the special burner 1, shown in Figure 4c, has been proposed.

According to said variant, the actuators 7 that move the sealing devices 6 of each INJ.n injector are all connected in series with each other by a single control line 3, in the present example of the pneumatic type (exactly like the INJ.n injectors that they comprise their own dedicated gas supply line 4).

Accordingly, according to said variant, all the shutter devices 6 of each INJ.n injector work at the same pneumatic pressure, depending on the subsequent presses exerted on the push button panel 2 of the special burner 1.

As is also clearly shown in Figure 6, according to the present variant, said push button panel 2 may comprise at least one button 20.1 called "ignition", adapted to activate the IGN lighter and to allow switching of the valve SV security from its "normally closed" position to the "open" position (thereby activating the main flame zone FL1) and at least one button 20.2, called "selection", which behaves, as anticipated , as a volumetric "compression" pump adapted to discreetly increase the pressure of the control line 3 at each repeated pulsation thereof, so that the adjacent FLn flame zones of the flame will be sequentially activated in the ways to be described. special burner 1.

On the other hand, pressing and holding down said selection button 20.2 opens a discharge orifice that allows the escape of air from the control line 3, quickly and interactively reducing the pressure of the same with the consequences will describe below.

According to said variant, another safety discharge device comprises a "normally open" DV discharge solenoid valve, in communication with the external environment of the home, which can be piloted by means of the ignition button 20.1 and held in

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a closed position by the flame detector FD.

In the absence of a flame in the main flame zone FL1 or in the event of an accidental shutdown thereof, said discharge solenoid valve returns to its normally open position by discharging the compressed air and causing the closure of all sealing devices 6 of INJ injectors to which control line 3 serves; this consequently ensures an additional level of safety for the special burner 1.

At this point, a first possible architecture for the INJ.n injectors and the relevant shutter devices 6 of the pneumatic control type, represented with multiple views in Figure 8 will be described in greater detail and precision.

More particularly, of said injector INJ.n are represented: a nozzle 80 and a gas compartment 81 connected to the fuel gas supply line 4 while from said device 6 a pneumatic chamber 60 is represented in fluid communication with the line of pneumatic control 3 above and the "pin" shutter 61 which can be moved from a "normally closed" position to a "open" position (and vice versa) of the nozzle 80 by, for example, the pneumatic actuator 7 above.

Said actuator 7 may comprise a pneumatic piston 70 and a mechanically adjustable stationary spring element 71 comprising an adjustable preload intended to keep its piston in a "normally closed" position, for example by means of a threaded bushing 72 or a screw.

According to a possible variant, said piston 70 may alternatively constitute a known bistable piston.

Sealing elements 62 keep the pneumatic chamber 60 and the gas compartment 81 strictly separated.

The pneumatic chamber 60, adjacent to the gas compartment 81 of the injector INJ.n, is in overpressure in relation to the outside environment such that the emission of combustible gas to the outside (for example, on the countertop) in the counter is avoided. case of damage / or wear of the sealing elements 62.

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Accordingly, by properly managing the pressure level inside the pneumatic chamber 60, the pressure gradient between the combustible gas and the fluid (generally compressed air) of the pneumatic control line 3 on the air element can be systematically limited or eliminated. sealed 62. This materializes by ensuring an operating pressure of the pneumatic control line of the shutters 6 in the vicinity of the fuel gas supply pressure, for example by means of two non-return valves (not shown): one in series with the device of leakage of the pneumatic control line 3, preferably coinciding with the previous DV discharge valve; the other at the outlet of the air inlets 26.

By adjusting the opening of said non-return valves to the fuel gas supply pressure and properly adjusting the preloads of the previous stationary spring element 71 of each actuator 7:

- with the special burner 1 on (for example, by simultaneously pressing the power buttons 20.1 and selection 20.2), each subsequent press of the selection button 20.2 will correspond to a discrete increase in the pressure in the control line 3 to the minimum level necessary for the opening of the first closed shutter in the sequence of the shutter devices 6 of each injector INJ.n

- with the special burner 1 lit by pressing the selection button 20.2 fully (which, as can be seen, works as a volumetric pump), a pressure reduction can be obtained in the different sealing devices 6 of the INJ injectors. they close one by one sequentially until the minimum pressure of the pneumatic control line is reached (in fact, the same as that of the gas supply). With the special burner 1 turned off, therefore, the pressure gradient between the pneumatic chamber 60 and the gas compartment 81 is canceled and thus the risk of gas leakage to the outdoor environment of the home.

The overpressure generated in the pneumatic chamber 60 intended to keep the special burner 1 on would lead, in case of damage of the sealing element 62, to an air leak to the gas compartment 81, however without particular problems, since it would automatically reduce the pressure of the pneumatic control line 3 inducing the sequential and simultaneous closure of the shutters 6 of the injectors INJ.n.

In the case where the minimum pressure of the pneumatic control line is equal to the

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Atmospheric, in case of damage of the sealing element 62 of the injector INJ.n, a leakage of the combustible gas would occur inside said pneumatic line 3; this does not constitute any danger since said pneumatic line 3 has a very small interior volume, is water tight and a very small amount of combustible gas leaks.

With the burner 1 off, SV is, as can be seen, in the "closed" position and the gas that has possibly leaked in the control line 3 circulates away through the discharge valve DV or remains confined along it line if said DV valve is equipped with the above-mentioned non-return valve adjusted to the gas pressure.

However, the sealing devices 6 of the plurality of INJ.n injectors are, as observed, in the "normally closed" position thereby preventing the flow of fuel gas into the respective INJ.n injectors; therefore, said ignition and power modulation system of a special burner 1 is intrinsically safe.

An ignition (or shutdown) and thermal power adjustment view of a special burner 1 according to said variant is shown in Figure 6 and provides, by a non-limiting example, the following steps: once the special burner 1 is it is activated at its minimum thermal power (that is, the only main zone FL1 is enabled; see (i) and (ii) in figure 6), a subsequent succession of pulsations will correspond to the ignition of the flame zone Immediately contiguous FL2 (see (iii) in Figure 6); a possible subsequent and long press on the same selection button 20.2 will lead, on the contrary, to the deactivation of the last flame zone FLn activated (in this case the second flame zone FL2) and a consequent reduction of its power level (see (iv) in Figure 6).

If said special burner 1 was already at the minimum power (only the FL1 area is lit), said long press of the selection button 20.2 will cause its final shutdown.

Alternatively, the pneumatic control system intended for ignition of the special burner 1 of the present invention may also be of the "vacuum type"; therefore, figure 9 represents the related button 20.n.

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According to said variant, the at least one button 20.n of the push button panel 2 consists of a tubular body comprising an outer lining 21 fixed to a support (for example, to the aesthetic face of the countertop P) comprising, in turn, a connection channel 22 to the pneumatic control line 3 and an associated non-return valve VNR1.

A movable key 23 can move vertically, when pressed, inside said fixed lining 21 so that it opens, for the reasons that will be clarified below, said "normally closed" valve VNR1.

Once key 23 is stopped, an inner pre-compressed spring element 28 can return said valve VNR1 to the "normally closed" position.

Between the bottom 230 of said key 23 and that of said outer lining 21 there is a sealed chamber 24 for the pneumatic control line 3, said chamber 24 varying its volume according to the above-mentioned vertical displacement of the key 23 of the button 20.n.

By partially pressing the key 23 (as a partial press, an insufficient pulsation is understood to move the button to the bottom), inside this collecting chamber 24, a vacuum is generated that opens the non-return valve VNR1 and draws air of the pneumatic line 3 (which is depressurized); Then releasing the same key 23, said non-return valve VNR1 will immediately close by means of the pre-compressed recovery spring element 27, said recovery spring 27 being able to re-compress the collecting chamber 24 until the opening of a VRN2 discharge valve arranged at the bottom. 230 of it.

Said sequence can be repeated to continue increasing the vacuum of the control line 3.

By pressing key 23 to the bottom, the alignment of the lateral grooves 25 of the outer lining 21 with so many air intakes 26 of said sealed chamber 24 is obtained in such a way that it allows the ambient air to penetrate the pneumatic control line 3 by turning it to compress; this corresponds to the closure of the shutter devices 6 of the injectors INJ.n served by said control line 3.

It should be noted that the at least one button 20.n intended for the pneumatic system of

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"Compression" described above and shown in Figure 8 may be constructively identical to that of "vacuum" except for the reversal of the operating direction of the two valves VNR1 and VNR2.

A particular application of said pneumatic vacuum control is shown in Figure 4f, and according to it the activation of the special burner 1 is managed by an individual button 20.n which can act on a micro switch MT of an electromechanical control group SWT , properly connected and / or wired to the IGN lighter, to the DV discharge and safety valve SV that can intercept the fuel gas supply line 4.

According to said version, starting from the special burner 1 in the OFF configuration, with a first partial press on button 20.n exerted for a predetermined period of time (preferably a few seconds), said electromechanical group SWT is responsible, by means of specific signals along suitable dedicated connection wiring, of the closing of the discharge valve DV, simultaneously opening the safety valve SV and enabling the IGN lighter intended for ignition of the main flame zone FL1.

When said button 20.n is released, the same electromechanical group SWT cuts the signal to the IGN lighter as well as to said DV discharge valves and SV safety valves.

If the ignition of the special burner 1 has occurred, the above-mentioned FD flame detector will keep the discharge valve DV in the "closed" configuration and the safety valve SV in the "open" position; if not, the safety valve SV closes immediately, interrupting, as can be seen, the circulation of gas to the burner 1, while the discharge valve DV opens to restore the pressure along the pneumatic control line 3 of the INJ.n injectors preventing gas leaks.

It is not necessary to stop in the modulation of the thermal power of the special burner 1 (sequential ignition / shutdown of the adjacent flame zones FLn), since it is totally similar to what has been observed and described up to this point.

On the other hand, it is necessary to specify that the activation of the IGN lighter preferably occurs with a preset delay time in relation to the pulse in the

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button, thus avoiding unnecessary ignitions thereof also during the modulation of the thermal power of the special burner 1 of the present invention.

The same optimization and simplification of the control line of the injectors INJ.n of the special burner 1 of the present invention, as anticipated, can also be obtained by providing sealing devices 6 electrically and / or electronically managed.

According to said variant schematically represented in Figure 4e, the actuators 7 of each shutter 6 are preferably:

- known actuators of the electrical type comprising, as discussed, excitation coils of the associated electromagnets, electrically connected in parallel with each other, and sized to accept a predetermined range of voltage values

- connected in series with each other and powered by the same power line 3 (for example, single-line type).

An electrical control circuit CMD, connected to the push button panel 2, transforms each press on button 20.1 and / or 20.2 into a voltage signal that increases or decreases discreetly, obtaining a modulation of the thermal power of the special burner 1 (see steps (i), (ii), (iii), (iv) of Figure 7), similar to what is achievable with the pneumatic system described above.

The simultaneous pressure of the two buttons 20.1, 20.2 with the burner 1 off determines, on the other hand, the ignition (more particularly, the activation of the main flame zone FL1, as shown in (i) of Figure 7).

More particularly, the opening or closing of each INJ.n injector can be obtained by providing different alternative solutions.

For example, in case of different electric actuators 7 for each INJ injector, it will be enough to size the coil of its coil differently to obtain the activation of the shutter 6 relevant only to the suitable level of the voltage signal from the CMD electrical control circuit .

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Obviously, the same result can be obtained by providing identical electric actuators for all shutters 6 of the INJ.n injector but stationary spring elements sized differently to obtain activation of the shutter device 6 associated only with a suitable level of the electrical signal (for example, voltage or intensity) from said electrical control circuit CMD; more particularly, as said level of the voltage signal generated by pressing the button increases, all the electric actuators 7 will sequentially exceed the antagonistic force of the associated stationary spring element by activating the shutter 6.

Conversely, for the reduction of the power of the special burner 1, with each step of reduction of the control signal managed by the CMD control card, each stationary spring element will exceed the electromagnetic force of the respective electric actuator 7, closing in this way the shutter device 6 on which they rest.

Obviously, a combination of the two solutions mentioned above is also possible.

According to another alternative, electric actuators 7 and stationary spring elements all identical to each other can be provided. In such a case, the sequential opening or closing (more particularly the "activation") of the shutter is obtained simply by adjusting the preloads of its stationary spring elements at different values.

Finally, the possibility of using more advanced electric actuators 7 such as, for example, linear or similar stepper motors can be provided; in this case, the control line 3 would function as an effective data BUS, the master being the push button panel 2 and the associated CMD electrical control circuit (which functions as an effective electronic card that can perform calculations) and the slaves they are the actuators 7 of the shutters 6 of the injectors INJ.n that would interconnect with each other.

This entails additional advantages relative to mutual diagnosis and, ultimately, to higher levels of safety and reliability of the whole.

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Finally, Figure 4g represents a final variant of the control and adjustment system of a special burner 1.

Said variant provides an electrical control circuit CMD of the special burner 1 connected, on the one hand, to a push button panel 2 comprising a single button 20 and, therefore, can function as a power and selection button and, on the other side, to the individual electrical control line 3 of the injectors INJ.n.

In this case, a short press of said button 20 will correspond to a reduction in power (or shutdown of burner 1 if it is the only main flame zone FL1 active), while a long press corresponds to an increase in said power. It will be the CMD electrical control circuit that will recognize whether or not a long press of the button corresponds to the first ignition (that of the main flame zone FL1) depending on the reception or non-reception of the flame signal sent by the detector. call FD, to which it is connected.

In the event of a long press with the burner 1 in the OFF position, the CMD electric control circuit opens the safety valve SV that feeds the burner 1 with combustible gas, enables the IGN lighter, to which it is connected, and sends the signal to open the injector INJ.1 installed upstream of the main flame zone FL1 by said electrical control line 3.

As already covered for the pneumatic case, when the button 20 is released, if the ignition has been successful, the signal generated and coming from the flame detector FD will keep the safety valve SV open; otherwise, the CMD electric control circuit will close said safety valve SV and the injector INJ.1 of the main flame zone FL1.

At this point, countertop management logics that integrate a plurality of said special burners 1 and the associated ignition and modulation systems described above can be described.

In the following examples, reference will always be made, without any intention of limitation, to the electrical / electronic variants of the control and adjustment system intended for the special burners 1 with the understanding that everything that will be said can be extended

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also to pneumatic versions.

By way of example only, Figure 10 represents a countertop P comprising four special burners 1 of the type described, each comprising, in turn, four INJ injectors that feed, as observed, a equal number of flame zones FLn. The countertop represented has three levels of security; a first safety level (called "base level") is protected by a general safety solenoid valve SSV ("normally closed") that can disconnect the general line L destined for the supply of fuel gas (represented in figure 10 by the gray line thick and from it, downstream of the same SSV valve, a plurality of gas supply lines 4 is connected, one for each individual burner 1, shown in the figure with "dotted line") when no special burner 1 is lit . A second safety level is represented by the safety valves SV (as can also be seen "normally closed") supplied with each burner 1 and adapted to interrupt the fuel supply line of the individual burner 1 (dotted line of Figure 10 ) in the absence of the confirmation signal from your FD flame detector; a third level of safety guaranteed by the shutters 6 of each INJ.n injector connected in series through an individual control line 3 (see the dotted and dotted line of figure 10), the electrical control circuit CMD that transmits a closing signal when the flame detector FD detects the accidental shutdown of the flame or when the burner 1 goes out.

Said redundancy can be advantageously used to make simplified versions of the countertop P that always comprise at least two levels of security. Even in the absence of the general safety valve SSV, safety against leaks of combustible gas in the absence of flame would be guaranteed by at least the safety valve SV of each special burner 1 and by each shutter of the plurality of INJ injectors. n that feeds him.

Another simplified variant, shown in Figure 11, is provided by the absence of the safety valve SV of the special special burner 1. Even in this case, a basic level of safety is still guaranteed by means of the general safety valve SSV and a second level of safety is guaranteed by the shutters 6 of the injectors INJ.n of each special burner 1. In this case, all Flame detectors FD of the plurality of special burners 1 of the countertop P are connected directly,

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by means of the cables 55, to the general safety valve SSV, thus being able to return to the "normally closed" position already in the case of an accidental shutdown of the flame of one of said burners 1 of the worktop P.

The distinction between accidental shutdown and voluntary shutdown of each special burner 1 is guaranteed by the CMD electrical control circuit depending on the reception or not of the flame signal by the respective flame detectors to which, as noted, it is is connected

Figure 12 represents another variant, according to the same safety function that constitutes the closure of the injectors INJ.n in the case of accidental shutdown of the flame, instead of being assigned to the CMD electrical control circuit, it is attributed to relays Special safety devices K (for example, double entry, one of which is timed), normally open, one for each special burner 1. In this version, the safety function of disabling the INJ injectors in the event of accidental shutdown of the flame (the signal from the flame detector FD is missing) has been attributed to special safety relays normally open K (i) (for example of the semiconductor type). Each relay is connected in series with the control line 3 of its INJ.n injectors in such a way that it disconnects in case of absence of the flame; while the flame signal from said FD detector can keep it in the closed position. To allow the first ignition, the CMD group will provide a first signal (for example a voltage) to the control line 3 of the burner injectors of the Lk level just below the minimum activation level of the INJ.1 injector (which will be called L1). The signal level Lk must be able to close K (i) but not be sufficient to open the first injector of the series. The device K (i) can be equipped with a timing such that, after a few seconds from the first reception of the signal Lk, K (i) can be kept closed only by the flame detector signal FD and, in the absence thereof , returns to the open position forcing the user to repeat the procedure of the first ignition. In this way, overlaps between the burner power level control signal (L1 <L2 <L3 <L4) and the ignition signal Lk (where Lk <L1) are avoided.

Likewise, nothing prevents providing another constructive variant (see Figure 13) comprising an SFT safety functional group that is assigned the task of constantly receiving the flame signals from the FD flame detectors of each special burner 1 of the countertop P and compare them with the status information of

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ignition of said burners 1 from the CMD electronic control card.

According to said variant, in the case of an accidental shutdown of the special burner 1, the safety functional group SFT will order the closing of the general safety valve SSV.

By means of the data line 56 that connects it to the CMD electronic control circuit, the SFT safety functional group can also force the general safety valve SSV to go to the "open" configuration in the case of the first ignition of the burner 1 ( that is, as has been repeatedly stated, of its main flame zone FL1). Finally, said data line 56 allows the electrical control circuit CMD to receive information about the presence of flame and close, by means of the associated control lines 3 of the shutters, all the injectors INJ.n in the case of shutdown accidental or failure of burner ignition 1.

Finally, Figure 14 represents a final constructive variant of a worktop P comprising:

- a single gas supply line 4, downstream of the general safety valve SSV, which connects all the injectors INJ.n of all the special burners 1, feeding them successively (by way of non-limiting example, starting from the injector INJ. 1 of the special burner 1 indicated as BRN1, to the injector INJ. 4 of the special burner 4 of the countertop P indicated as BRN4)

- a single continuous control line 3 which, from the CMD electronic control circuit, joins in a sequence all the special burners 1 of the same countertop P (instead of having as many dedicated control lines as burners 1 of the countertop P , as in the constructive examples of Figures 10 to 13), said individual control line 3 serving, as is observed, to all INJ.n injectors of each burner. Said control line 3 is a BUS that connects all the electric actuators 7 that are of the bistable (or similar) type that are interlocked and directed by the CMD device.

It is clear that in the practical embodiment of the present invention numerous modifications and other variants can be provided, all of which comprise the same inventive concept. All of the various elements and details described

previously they can also be replaced by technically equivalent elements.

For example, in the case of very large FLn flame zones, the term INJ.n can be understood to be also a group of INJ.n injectors, all of which provide service to the same FLn flame zone, it being understood that said group of injectors INJ.n is piloted as an individual injector INJ.n.

With the control and management system of a special burner 1 of the present invention the stated objectives are achieved, in particular the possibility of a discrete and intuitive adjustment 10 of the thermal power (shown in Figure 3b) thereof which can be understood easily and immediately even users with little experience. The presence of a single fuel gas supply line 4 destined for the special burner 1 and, for the variants that provide it, of a single electric / electromechanical or pneumatic control line 3, destined for all INJ injectors thereof, It also allows considerable constructive simplification of the countertops that incorporate said special burners 1 with undoubted advantages, even from an economic point of view. Finally, the use of INJ.n injectors that integrate an associated sealing device 6, normally closed with the burner off or in case of accidental flame shutdown, ensures an additional level of safety against leaks 20 and leaks of combustible gas .

Claims (25)

5 10 fifteen twenty 25 30 35 1. Special atmospheric burner (1) intended for a worktop (P) comprising: - a plurality of contiguous flame generation zones (FLn), - a plurality of ejectors (EJ.n) adapted for the mixture of combustion air and combustible gas, said ejectors (EJ.n) serving said plurality of flame generation zones (FLn) - a plurality of injectors (INJ.n) intended for the supply of said fuel gas in said ejectors (EJ.n), each injector (INJ.n) being arranged at the corresponding ejector inlet (EJ.n), of said plurality of contiguous flame generation zones (FLn) are identified: - a main flame zone (FL1) equipped with a lighter device (IGN) and a relevant flame detector (FD) and fed by the corresponding injector (INJ.n) of said plurality of injectors (INJ.n), feeding on first said said main flame zone (FL1) - one or more additional flame generation zones (FLn), each of them fed by a respective injector (INJ.n) of said plurality of injectors (INJ.1), said one or more generation zones being able to be fed and activated additional flame (FLn) sequentially one after the other each pair of flame generation zones (FLn), including the main one (FL1), which are fed sequentially, being adjacent to each other such that, upon activation of said main flame zone (FL1), none can be energized and activated without there being at least one contiguous flame generation zone (FLn) already lit. characterized because said injectors (INJ.n), each adapted to service a dedicated and specific flame generation zone (FLn) of said special burner (1): - they are connected and fed in series along an individual supply line (4) of said combustible gas 5 10 fifteen twenty 25 30 35 - they are activated by means of an individual control line (3) adapted to serve all the injectors (INJ.n) of said plurality of injectors (INJ.n) and are connected to a push button panel (2; 20.n) , said panel of push buttons (2) comprising at least one button (20.n) which can be pressed according to a specific sequence and / or ignition mode of said flame generating zones (FLn) of said special burner (1) and because said individual control line (3; 3.1 ... 3.n) is connected to an electrical control circuit (CMD): - adapted to receive signals from at least said push button panel (2) and said flame detector (FD) by means of the respective cables (53, 51) - to send control signals to said lighter device (IGN) and to a safety valve (SV) arranged along said individual supply line (4) upstream of said plurality of injectors (INJ.n) by means of the respective wiring (52, 50). 2. Special burner (1) according to any of the preceding claims, characterized in that it comprises a double safety system against fuel gas leaks in the event of incomplete ignition or accidental failure thereof comprising at least: - said safety valve (SV) "normally closed", said safety valve (SV) being controlled by said push button panel (2) to switch to an "open configuration" suitable for the passage of said combustible gas to said plurality of injectors (INJ.n) - a "normally closed" sealing device (6) of each of said plurality of injectors (INJ.n) that can allow or prevent, when operated, the exit of said combustible gas towards a corresponding ejector (EJ.n) intended for the activation of the associated flame generation zone (FLn), although at the same time assuring its passage to the next injector (INJ.n), consequently acting each of said plurality of injectors (INJ.n) also as a Closing valve. 3. Special burner (1) according to the preceding claim, characterized in that 5 10 fifteen twenty 25 30 35 said safety valve (SV) and said shutter device (6) of each of said plurality of injectors (INJ.n) are interlocked with said flame detector (FD), said safety valve (SV) and said shutter device being able to (6) return to the "normally closed" configuration in the absence of a flame signal detected by the same flame detector (FD). 4. Special burner (1) according to any of the preceding claims, characterized in that said shutter device (6) of each injector (INJ.n) of said plurality of injectors (INJ.n) is controlled by a corresponding actuator (7) when switching from said "normally closed" to "open" configuration thereof, by returning a stationary spring element (71) of said actuator (7) to said sealing device (6) to its "normally closed" position when the impulse generated by said push button panel (2) ceases. 5. Special burner (1) according to the preceding claim, characterized in that said actuator (7) is an electromechanical actuator, said actuator (7) comprising a coil wound substantially around said sealing device (6) of each injector (INJ.n) of said plurality of injectors (INJ.n) and being able to convert the electrical signal transmitted to it by said push button panel (2) by said individual control line (3) in an electromagnetic field that causes a linear displacement thereof. 6. Special burner (1) according to the preceding claim, characterized in that said electromechanical actuators (7) of each of said sealing devices (6) of said injectors (INJ.n) are all different from each other, thus dimensioning the winding of the coil of each of said electromechanical actuators (7 ) differently to obtain the activation of the relevant shutter device (6) only at the appropriate level of the voltage signal from said electrical control circuit (CMD). 7. Special burner (1) according to claim 5, characterized in that 5 10 fifteen twenty 25 30 35 said electromagnetic actuators (7) of each of said sealing devices (6) of said injectors (INJ.n) are all identical to each other, the stationary spring elements (71) of each of said actuators (7) being differently sized to obtain the activation of the relevant shutter device (6), only at the suitable level of the voltage signal from said electrical control circuit (CMD). 8. Special burner (1) according to claim 5, characterized in that said electromechanical actuators (7) of each of said sealing devices (6) of said injectors (INJ.n) and said relevant stationary spring elements (71) are all identical to each other, obtaining the sequential activation of said sealing devices ( 6) adjusting the preloads of said stationary spring elements in different values. 9. Special burner (1) according to claim 5, characterized in that said actuators (7) of each of said shutter devices (6) of said injectors (INJ.n) may comprise stepper motors, or the like, said individual control line (3) being a data BUS, in the that the master is said push button panel (2) and the relevant electrical control circuit (CMD) and the slaves are said actuators (7). 10. Special burner (1) according to any of the preceding claims, characterized in that said sealing device (6) and the corresponding injector (INJ.n) form a single valve body. 11. Special burner (1) according to any of the preceding claims except 10, characterized because said sealing device (6) and the corresponding injector (INJ.n) are logically and physically separated elements. 12. Special burner (1) according to any of the preceding claims, 3. 4 5 10 fifteen twenty 25 30 35 characterized because said flame generation zones (FLn) may comprise a plurality of concentric flame crowns or have other shapes as long as each of them is contiguous to all of the following. 13. Special burner (1) according to any of the preceding claims, characterized in that The ejectors (EJ.n) are ejectors of the "Venturi vertical" STD or "Horizontal Venturi" type LIN. 14. Special burner (1) according to any of the preceding claims, characterized in that said push button panel (2) can be electromechanical or electronic. 15. Special burner (1) according to claim 14, characterized in that said push button panel (2) is an electronic push button panel comprising a pair of buttons (20; 20.1, 20.2), said push button panel (2) controlling each injector (INJ.n) of said special burner ( 1) by means of said individual electrical control line (3), said individual electrical control line (3) being connected to said electrical control circuit (CMD) which can transform any pressure in said pair of buttons (20; 20.1, 20.2) into a voltage signal that increases or decreases discreetly and in such a way that it sequentially activates said injectors (INJ.n) of said plurality of injectors (INJ.n). 16. Special burner (1) according to claim 14, characterized in that said push button panel (2) comprises a single button (20) that can function as an ignition button and select button, said single button (20) being connected to said electronic control circuit (CMD), in turn connected to said injectors (INJ.n) by said individual control line (3), a short press of said single button (20) corresponding to a reduction of the thermal power of said special burner (1) while a long press corresponds to an increase of said thermal power, said electronic control circuit (CMD) being the type that can recognize if said 35 5 10 fifteen twenty 25 30 35 Long press will or will not correspond to the first ignition of said special burner (1) depending on whether or not the flame signal sent from said flame detector (FD) is received. 17. Special burner (1) according to any of the preceding claims, characterized in that it comprises a single flame detector (FD) and a single lighter (IGN). 18. Countertop (P) comprising two or more special burners (1) according to claims 1 to 17, characterized in that it comprises at least two levels of safety against fuel gas leaks. 19. Worktop (P) according to the preceding claim, characterized in that said at least two levels of security include: - the safety valve (SV) supplied with each special burner (1) of said worktop (P) and adapted to interrupt the fuel gas supply line (4) to the individual burner (1) - the sealing device (6) to close each injector (INJ.n) of each burner special (1). 20. Countertop (P) according to claim 18, characterized in that said at least two levels of security include: - the general safety valve (SSV) that can interrupt the general gas supply line (L) to said special burners (1) - the sealing device (6) to close each injector (INJ.n) of each special burner (1) 21. Countertop (P) according to the preceding claim, characterized in that the flame detectors (FD) of each special burner (1) of said countertop (P) are 36 5 10 fifteen twenty 25 30 35 connect directly to said general safety valve (SSV), said general safety valve (SSV) being able to return to the "normally closed" position in the event that the flame of at least one of said special burners is extinguished (1 ) of said countertop (P). 22. Countertop (P) according to claim 18, characterized in that said at least two levels of safety against leaks of combustible gas comprise three levels of security, said three levels of security constituting: - a safety valve (SSV) that can interrupt the fuel gas supply line (L) to said special burners (1) - a safety valve (SV) supplied with each special burner (1) of said countertop (P) and adapted to interrupt the fuel gas supply line (4) to the individual burner (1) - the sealing device (6) to close each injector (INJ.n) of each special burner (1). 23. Countertop (P) according to claims 18 to 22, characterized in that The closure of said injectors (INJ.n) in the event that the flame goes out accidentally is assigned to an electronic control circuit (CMD). 24. Countertop (P) according to claims 18 to 22, characterized in that The closure of said injectors (INJ.n) in the event that the flame goes out accidentally is assigned to "normally open" timed relays (K), one for each special burner (1) of said countertop (P). 25. Countertop (P) according to claim 18, characterized in that it comprises - an individual gas supply line (4), which can connect all the injectors (INJ.n) of all said two or more special burners (1) of said countertop (P), feeding them in succession 37 - an individual control line (3) that can join in a sequence all two or more special burners (1) of said countertop (P), said individual control line (3) serving all said injectors (INJ.n ) of each of said two or more burners (1). 5