Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
  • F23D—BURNERS
  • F23D14/00—Burners for combustion of a gas, e.g. of a gas stored under pressure as a liquid
  • F23D14/46—Details, e.g. noise reduction means
  • F23D14/72—Safety devices, e.g. operative in case of failure of gas supply
  • F23D14/725—Protection against flame failure by using flame detection devices
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
  • F23D—BURNERS
  • F23D14/00—Burners for combustion of a gas, e.g. of a gas stored under pressure as a liquid
  • F23D14/02—Premix gas burners, i.e. in which gaseous fuel is mixed with combustion air upstream of the combustion zone
  • F23D14/04—Premix gas burners, i.e. in which gaseous fuel is mixed with combustion air upstream of the combustion zone induction type, e.g. Bunsen burner
  • F23D14/06—Premix gas burners, i.e. in which gaseous fuel is mixed with combustion air upstream of the combustion zone induction type, e.g. Bunsen burner with radial outlets at the burner head
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F24—HEATING; RANGES; VENTILATING
  • F24C—DOMESTIC STOVES OR RANGES ; DETAILS OF DOMESTIC STOVES OR RANGES, OF GENERAL APPLICATION
  • F24C3/00—Stoves or ranges for gaseous fuels
  • F24C3/08—Arrangement or mounting of burners
  • F24C3/085—Arrangement or mounting of burners on ranges
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F24—HEATING; RANGES; VENTILATING
  • F24C—DOMESTIC STOVES OR RANGES ; DETAILS OF DOMESTIC STOVES OR RANGES, OF GENERAL APPLICATION
  • F24C3/00—Stoves or ranges for gaseous fuels
  • F24C3/10—Arrangement or mounting of ignition devices
  • F24C3/103—Arrangement or mounting of ignition devices of electric ignition devices
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
  • F23D—BURNERS
  • F23D2207/00—Ignition devices associated with burner

Definitions

• Gas burner in particular for a culinary appliance, and methods for mounting and using it.
• the present invention relates to a gas burner for a culinary appliance such as a stove or a hob.
• the present invention also relates to a method for mounting and using a gas burner for a culinary appliance.
• Each of these two types comprises a gas m ector opening into a mixing chamber in which the gas is first mixed with air, called “primary air”. This mixture then passes through a venturi which leads it to flame orifices. At the exit of these the mixture undergoes combustion thanks to the addition of a second quantity of air, called “secondary air"
• the two types of burners mentioned above are distinguished by the method of supplying the primary air in the mixing chamber.
• a first type known from the journal ENERGIETECHNIK, 3 l ⁇ me ferment, n ° 5, May 1958, page 230 the primary air is taken above the hob, through an annular interval between the hob and the free edge of a peripheral skirt of the burner superstructure.
• the tank is generally closed. Closing the tank has advantages, in particular with regard to certain flame stability standards in the event of a "gust of wind" in the region situated below the hob.
• These burners provide unsatisfactory primary ventilation, since the path of primary air from the annular interval and bypassing the base of the venturi path, presents high pressure drops.
• these burners are subject to r_sque ⁇ extinguishing flames when a flooding of the hob closes the annular gap and / or reaches the mixing chamber from the top of the hob, by the same route as the primary air.
• the second type of burners known from FR-A-1 197 178 (SAUTER), have a mixing chamber open laterally, making it possible to take the primary air in the region of the appliance located below the hob
• These burners have poor resistance to gusts of wind which may occur below the hob, for example in the event of the sudden closing or opening of an access door to the volume located under the hob. cooking.
• the object of the invention is thus to propose a gas burner having great flexibility of use from the point of view of its mounting, and / or of the quality of its combustion even for different kinds of gas, and / or its security .
• the gas burner comprising a tank, a gas m ector opening along an axis of the tank, primary air inlet means in the tank, a superstructure placed above the tank and defining a venturi having an open orifice opposite the in ector, the venturi leading to flame orifices distributed annularly, is characterized in that the primary air intake means comprise a main path converging towards the axis of the tank from at least one inlet means arranged in a ring around the periphery of the tank, and a complementary path comprising at least one complementary opening made through the wall of the tank
• the burner according to the invention ensures a very strong ventilation primary therefore excellent combustion quality, in particular with regard to standards on the maximum level of carbon monoxide.
• the burner is surprisingly effective against the risks of flame extinction. It is in particular surprising to note that the presence of the two journeys, instead of adding up the risks presented by each of the two journeys, on the contrary has the virtue of eliminating them. Thus, if the main path is blocked, the complementary path still provides some primary ventilation.
• the path through the tank is only a complementary path, ensuring an air flow for example about five times lower than the main path, its passage section is small and does not allow gusts of wind to reach the mixing chamber.
• the secondary path constitutes an orifice for discharging substances liable to accidentally reach the mixing chamber via the primary path. This security is notably ensured when, in accordance with an optional feature of the invention, the complementary path emerges at a low point of the mixing chamber.
• the additional path is arranged to provide, if the main path is blocked, primary ventilation just sufficient to meet the standards relating to maximum levels of carbon monoxide in the combustion gases produced by the burner flame.
• the section of the complementary path is as small as possible so that all of the above advantages are optimally obtained. It has been found, according to another feature of the invention, that the complementary path should preferably be arranged to provide primary aeration corresponding to approximately 10% of the stoichiometric value necessary for liquefied petroleum gas, which is the combustible more difficult. This 10% is added to the 50% that the main path of the primary air is able to provide.
• the burner therefore totals a primary aeration corresponding to 60% of the stoichiometric aeration This is remarkable and then allows, thanks to the secondary aeration, combustion producing very low carbon monoxide levels, located very below the standards currently in force.
• the primary air path extending between the primary air intake means and the tank can be achieved with a very reduced pressure drop by
• the axial part of the venturi, leading to the neck and to the diverging part oriented radially, can be considerably shortened without degrading the operation of the venturi. It is thus able to achieve a path
• the method for associating a gas burner with a hob comprising a wall which is terminated by a peripheral upe and which limits the upper side of a space 0 adjacent to the hob, this space communicating with a mixing chamber formed in a tank provided with a gas in ector, process in which the burner tank is associated around an opening in the hob, is characterized in that puts the free edge 5 of the upe substantially in contact with the hob and establishes a communication between the mixing chamber and the region under the cooktop outside the tank.
• the method of using a gas burner comprising a tank defining inside a mixing chamber into which opens a gas injector, and a superstructure comprising a wall which is terminated by a upe peripheral and which limits the upper side of a primary air path opening into the tank, the superstructure being capable of stable positioning relative to the tank, this burner being adapted to be associated with a hob so that the free edge of the skirt is at a certain distance from an upper face of the table to form a primary air inlet between the free edge of the skirt and the table, is characterized in that, depending on the use, on the contrary the free edge of the upe in contact with the table along a line which surrounds air passages provided through the table radially outside the tank, so that the air path p rimaire is supplied with primary air from under the table, through said passages
• a burner of a structure hitherto known for supplying primary air from above the hob becomes usable for making a burner supplied from below the hob, with a large passage section
• the third object of the invention more particularly states that the same burner can be mounted in two different ways, that is to say either in the conventional way with primary air intake from above the table or else new way, also included in the second object, with intake of primary air through passages made in the hob
• FIG. 1 is a view, partially in axial section, of a burner according to the invention
• - - Figure 2 is a partial view of the burner according to Figure 1, in section along the plane II, -
• FIG. 3 is a view similar to Figure 1, but with partial section in another axial half-plane;
• FIG. 4 is a view, in axial section and in perspective, of the burner of FIG. 3, illustrating the disassembly of the spark plug, -
• FIG. 5 is a view of a detail in section along V-V of Figure 3, -
• FIG. 6 is a view of a detail along VI-VI of Figure 4.
• FIG. 7 is a half view of the burner, in section along another axial plane, -
• FIG. 8 is a partial perspective view illustrating the disassembly of the flame detector of Figure 7;
• FIG. 9 is a sectional view along IX-IX of Figure 1
• - Figure 10 is a detail in axial section, on an enlarged scale, of the connection of the burner with a gas pipe, - and
• FIG. 11 is a half-section view illustrating the assembly and use methods according to the invention.
• the gas burner comprises a tank 1 of generally frustoconical shape.
• the open upper edge of the tank has a peripheral flange 2 intended to be fixed against the underside of a hob 3, by means of screws 4.
• the hob 3 has an axial opening 5 with respect to which is centered 1 open end of the tank 1.
• the bottom of the tank 1 carries a fuel gas injector 6 mounted so as to release the combustible gas in a jet extending upwards along the vertical axis 8 of the tank 1 and the opening 5.
• the interior of the tank 1 constitutes a mixing chamber 9 in which the gas 7 is intended to mix with combustion air called "primary" air, taken from the atmosphere
• a main path of primary air 11 is arranged between the upper face of the hob 3 and the lower face of a wall 12 which belongs to an upper body 17 of the burner.
• the wall 12 is terminated, radially outward, by a skirt 13 oriented obliquely downward, therefore towards the upper face of the hob 3
• the free edge 14 of the upe 13 and the upper face of the hob 3 define between them an annular inlet interval for the main primary air over the entire periphery of the burner.
• the upper body 17 belongs to a superstructure 16 of the burner. This further comprises a cover 18 covering the upper body 17.
• the upper body 17 comprises a central hole defined by a collar 19 projecting towards the mixing chamber 9 along the axis 8 and intended to conduct the mixture of gas and d primary air in a radial venturi defined between an upper face of the upper body 17 and a substantially planar lower face of the cover 18
• the radial venturi comprises, from the upper end of the collar 19, opposite the injector 6, a neck 21 of the venturi and a divergent 22 extending radially outward from the neck 21
• the divergent forms for the mixture a passage section which grows very rapidly, thanks to the cumulative increase in diameter, and in the distance between the upper face 23 of the upper body 17 and the lower face of the cover 18.
• the divergent 22 opens into an annular pressure relief chamber 24 which is separated from the main path 11 by the wall 12 Rad ial outside, the pressure recovery chamber 24 is limited by a side wall 26, the upper edge is crenellated and supports the cover 18.
• the slots form flame orifices 27, bounded above by the cover 18.
• the plane 28 containing the free edge 14 of the skirt 13 extends between the injector 6 and the free edge 29 of the collar 19 I the same applies to the plane of the upper face of the hob 3 in the substantially flat region which defines the main path 11
• the collar 19 does not protrude downward relative to a radial plane (substantially the plane 28) containing the main path il.
• the latter can therefore be substantially rectilinear until it must change direction to enter the collar 19. This is obtained without increasing the total height of the burner, by simply reducing the length of the collar 19, relative to the embodiments classics.
• the mixing chamber 9 is further supplied by a complementary primary air path 31 comprising a complementary opening 32 formed through the wall of the tank
• the complementary opening 32 extends through a boss 33 of the outer face of the tank 1, and opens into the mixing chamber 9 at a low point of the tank, near the injector 6.
• the opening 32 Parallel to its axis, the opening 32 has a certain length, giving the flow d air passing through it with a certain directivity, and making this air flow relatively insensitive to undesirable flows which may exist near the external walls of the tank 1 Thanks to the advantageous arrangement which has just been described for the complementary opening 32 , the complementary path 31 is almost rectilinear and parallel to the gas flow 7 entering the collar 19.
• one or more openings 32 of small section ensure a substantial flow with reduced pressure drop Thanks to the venturi effect, the gas jet 7 carries with it up to the pressure relief chamber 24 and flame orifices 27 the primary air arriving via the main and tra j 11 and via the complementary path 31. It has been found advantageous according to the invention that the main path 11 provides ventilation corresponding to approximately 50% of the stoichiometric value and that the complementary path 31 provides ventilation corresponding to 10% of the stoichiometric value for liquefied petroleum gas.
• the path 31 Even if the hob 3 is strongly flooded to the point of closing the opening between the hob 3 and the free edge 14 of the skirt 13, sufficient primary ventilation is still ensured by the path 31.
• the contribution equal to 10% of the stoichiometric value, normally provided by the complementary path 31, was chosen so that the path 31 barely ensures combustion in compliance with the standards on carbon monoxide emissions when, in the event of an operating incident, the path main 11 is inoperative. It is preferred according to the invention not to increase the primary air supply capacities via the complementary path 31, since it is also desired to minimize the risks of a gust of wind around the outside face of the tank 1 coming to disturb combustion in passing through the complementary path such as 31.
• FIG. 2 illustrates that it is possible, if desired, to have more than one complementary opening 32, which can then be of smaller section.
• the superstructure is positioned on the tank 1 by centering feet 34, allowing the main path 11 to pass between them.
• the base of the feet 34 rests on the edge of the tank 1.
• the hob 3 forms, around the opening 5, a dome 37 of smaller diameter than the free edge 14 of the skirt 13, so as to reveal, radially outside the dome, the annular interval of entry of the main path 11 of the primary air.
• FIGS. 3, 4 and 5 illustrate an aspect of the invention relating to the mounting of a spark plug 41.
• the active end 42 of the spark plug 41 is positioned in a generally semicircular cell 43 defined by the external face of the side wall 26 of the superstructure.
• One of the flame orifices 27 is located at the bottom (radially inside) of this cell 43, as shown in FIGS. 3, 4 and 5.
• the top of the cell is closed by the cover 18. This cell which opens radially towards outside, protects the spark plug and in particular its active end 42 with regard to food deposits, but has the drawback of making it more difficult to supply secondary air for ignition.
• the replacement of the candle is complex and often requires, according to the prior art, a large disassembly of the burner, making the operation difficult for the user of the culinary appliance.
• the candle is removable from above the hob.
• the body of the candle extends through an ear 44 of the peripheral flange 2 of the tank 1.
• the candle 41 has a lateral fixing plate 46 which is placed on the upper face of the ear 44 and can be screwed to the ear 44 by means of a screw 47. The plate 46 extends towards the axis 8 of the burner.
• connection lug 49 connected to a high voltage supply wire 48.
• the assembly comprising the spark plug 41 and the adjacent end of the wire 48 can be pulled over the hob 3, this after moving away from the superstructure 16, as shown in FIG. 4.
• the wire 48 there it is possible to disconnect the wire 48, replace the spark plug 41 with an identical new spark plug, reconnect the wire 48 on the connection lug 49 and then reassemble the spark plug 41 using the screw 47.
• the periphery of the opening 5 of the hob 3 forms a notch 52 into which the upper face of the ear 44 fits.
• the body 45 of the spark plug extends upward through the path 11 of the primary air and through an opening 53 made in the wall 12.
• the active end 42 of the spark plug protrudes thus in the cell 43 forming a flame zone for the ignition flame.
• the opening 53 is large enough to provide around the body 45 of the spark plug a substantial clearance forming a path 54 for secondary air which is taken in the path 11 and ends in the cavity 43 at the outlet of the orifice flame 27 associated with this cell. The ignition of the burner is thus favored by an increase in secondary air.
• Figures 7 to 9 relate to another aspect of the invention relating to the mounting of a flame detector intended to control the cutting of the gas supply when the heating resulting from the presence of the flame disappears.
• FR-A-2 660 309 describes how such a detector can be produced by means of a thermocouple.
• the temperature-sensitive solder 61 forming the upper free end of the thermocouple 64, is placed substantially midway between the axes of two flame orifices 27 disposed at the bottom of a cell 62 formed by the outer face of the wall.
• lateral 26 of the superstructure FR-A-2 660 309 also describes other possible arrangements, also compatible with the present aspect of the invention, with in particular a single flame orifice influencing the welding 61 of the thermocouple
• thermocouple comprises approximately in the middle of its height a connection tab 63.
• the thermocouple 64 is fixed to the burner in a particularly simple manner by pinching the proximal part 66 of the tab 63 between the face bottom of the hob 3 and an ear 67 of the flange 2 of the tank 1.
• the ear 67 has on its upper face a recess 68 to accommodate the thickness of the proximal part 66, and a hole 69 for the passage from the bottom of the thermocouple downwards
• the hob 3 has a hole 71 to allow the top of the thermocouple to extend upward through the primary air path 11 This cools the cold junction (not visible in the figures) of the thermocouple
• the thermocouple then extends through an opening 72 formed in the wall 12 separating the path 11 on the one hand and the volume of the cell 62 on the other hand
• the opening 72 is dimensioned ée so as to present a considerable clearance around the thermocouple 64 so that a secondary air flow, taken from the primary air path it, passes through this clearance in the cell 62 and promotes the maintenance of the flames 73 licking the thermocouple hot solder 61 FIG.
• the tank 1 is made so as to comprise, when molded, a connection 83 allowing the pipe to be fixed to gas 81 to the tank 1 in a position where this pipe communicates with the injector 6 via a conduit 82 also coming from molding (see also Figure 1)
• the fitting 83 forms an enlargement at the open end of the conduit 82. This enlargement is defined by a threaded cylindrical interior surface 84 terminated internally by a convex conical shoulder 86.
• the thread 84 is intended to receive a clamping sleeve 87 externally threaded and having at its end turned towards the convex conical shoulder 86 a conical face corresponding concave 88.
• the pipe 81 has at its end a flare or conical flange 89 intended to be clamped between the faces 86 and 88 cited above.
• the flange 89 comprises, from the tubular part of the pipe 81, a part 91 extending conically towards the outside, followed by an end flange 92 folded against the inner face of the part 91
• the end flange 89 has an elasticity axial due to the more or less complete folding of the rim 92 against the part 91.
• FIG. 11 shows the methods according to the invention.
• a burner which may be strictly identical to that or those described hitherto, and therefore capable of being mounted as has been hitherto relative to the hob 3, can also be mounted on a hob.
• the burner described is capable, by simple difference of the shape of the hob, of operating as a burner taking at least a substantial part of its primary air above the hob or on the contrary by burner taking primary air only under the hob

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• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Gas Burners (AREA)

Priority Applications (4)

Applications Claiming Priority (1)

Publications (1)

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ID=9488917

Family Applications (1)

Country Status (4)

Cited By (8)

Citations (4)

• 1996
  • 1996-09-19 EP EP96932620A patent/EP0932797B1/de not_active Expired - Lifetime
  • 1996-09-19 PT PT96932620T patent/PT932797E/pt unknown
  • 1996-09-19 WO PCT/FR1996/001466 patent/WO1998012475A1/fr active IP Right Grant
  • 1996-09-19 ES ES96932620T patent/ES2210390T3/es not_active Expired - Lifetime

Patent Citations (4)

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