FR2697320A1 - Extra-flat gas burner with safety system intended particularly for cooking appliances for domestic use. - Google Patents

Abstract

Burner characterized in that it essentially comprises a support bowl (2), a body (3) and a head (4) and incorporating an ignition plug (14) and a thermoelectric couple (15) flame detector as a device of security; the head (4) has two cavities which form with the body (3) the corresponding enclosures (20, 21) which house the ignition electrode and the sensitive tip of the thermoelectric couple, enclosures provided with particular flame orifices respectively for the ignition and for the controlled heating of this sensitive tip. The parts have centering, guiding and fixing elements for quick and easy assembly after each cleaning.

Description

"Extra-flat gas burner with safety system intended for

  especially born to domestic cooking appliances "

  The invention relates to an extra gas burner.

  safety device dish, intended particularly for cooking appliances for domestic use fitted with a spark plug and a thermoelectric couple as a safety device, comprising a support bowl, a body and a head, where the support bowl-10 constitutes the pre-mixing chamber below the work table of the cooker, where the body comprises a central organ which constitutes the draft of the pre-mixing and a horizontal part which diverges towards the outside the expansion chamber of the mixture, the head, constructed in a single circular piece, constitutes at the same time the cover of the burner and the flame distributor through an annular wall with two formations of outlet orifices at different heights, where the spark plug and the thermoelectric couple are fixed to the support bowl and whose active tips are housed in diametrically opposite cavities of the head. We know:

  a gas burner (Energietechnik 8 Jg.

  Heft 5, May 1958) with primary air intake above the work table of the cooking appliance between a burner body and a burner supplement; a gas burner (patent FR 2 062 094) which has two openings for accommodating a spark plug and a safety device in peripheral positions diametrically opposite to the spill shelter and

  external aggressions and including a pre-

  feeling the formation of two outlet openings at a different height, one corresponding to the main flame and the other being connected to the pilot flame chamber; a gas burner (Belgian patent 902 029) o the bowl support delimits a pre-mixing chamber open upwards and whose closed bottom houses the injector, fixed to the plate of the appliance

  cook and o an element or body that covers the sup-

  toilet bowl holder has a central tubular part which delimits right through a hole with a vertical axis

  which extends downward into said chamber; this burn-

  presents them with mounting difficulties after each

  cleaning the burner because the body part is for

  view of guide ribs, the user must first seek an approximate orientation of the body guide ribs to then normally make several attempts to fit the body with the

  corresponding grooves in the bowl holder.

  The extra-flat gas burner which is the subject of the present invention has been designed for the upper part of cooking appliances, in particular those for domestic use, which require a flame safety device and an ignition and market

  fast, its line allowing the construction of burners

  their calorific value preferably

  taken between 1 k W and 4 k W, its double gas inlet and its reduced thickness making it adaptable to all

types of devices.

  The invention is characterized in that the annular wall of the head has two outward cavities forming, with the body, the enclosures o are housed the active tips of the candle and of the thermoelectric couple and o the concave enclosure of the

  candle formed by a semi-shaped front wall

  circular is provided with a special opening for

  ignition, the concave shape of the thermoelectric couple

  that being formed by a straight front wall and two straight lateral closures diverging towards the outside, the front wall being provided with two contiguous orifices which, having a diameter larger than that of the pilot flame orifices, allow heating sensitive tip control

of the thermoelectric torque.

  We know that, on the market for gas cooking appliances and also for surface burners, there is an increasing demand for a reliable and durable flame safety device to prevent fuel gas leaks. unburned,

  device which, in addition to enabling rapid ignition

  gas and convenient, avoids waiting times during frequent start-up of burners in upper parts of cookers, waiting times caused

  by the delay in the response of thermo-devices

  current safety sensitive kitchen appliances

  ner. On the other hand, this constitutes a requirement of

  safety that these devices also work quickly

  dementia in the event of accidental flame extinction

  and close the inlet valve before it occurs

  getting an excessive buildup of gas on the table

  work from the top of the stove.

  Given the need for a reduced cost of the device

  for cooking appliances for domestic use

  which is preferred in devices of this type, the allu-

  mage of the burner by spark and the device for

  curity based on a thermoelectric couple as a

  flame presence detector The requirement to improve the two response times of the safety device compared to the times currently required and to increase their duration requires incorporating both the spark plug and the torque thermoelectric flame detector to the burner itself and away from

  any deterioration that may be caused to these devices

  spills from cleaning product spills

age and mechanical aggression.

  The burner which is the subject of the invention, constructed in three compact basic parts, one

  lower part or support bowl, an inter-

  medial or body and an upper part or head, sa-

  meets the market requirements mentioned above by incorporating a spark plug for ignition and a special thermoelectric couple as a safety device

  flame detector with diametrically op-

  posed and giving the head and body a configu-

  ration such that two peripheral enclosures are formed

  where the active points of these devices are housed

  where they are protected by the cover of

  the head, two speakers o are supplied from

  particular flames of different flames and appro-

  required for different ignition and detection, a first closed enclosure associated with ignition, which has a crest on the internal face of the head

  coaxial with the candle to form a closing path

  ture of the electric arc which ignites the gas and a

  second enclosure, open and associated with the thermal couple

  moelectric, opened by a channel made in the peripheral edge of the body for greater access of

  cold air outside to speed up cooling

  softening of the sensitive tip of the thermoelectric couple

  if the flame goes out For a

  limited heating of the thermoelectric couple, preferably

  Between 5500 C and 6500 C, there are two contiguous outlet orifices in the distributor, the flames of which rub alongside the sensitive tip of this device, an upper temperature limit imposed by the life limit and a lower limit necessary for the maintenance of the safety valve in the open valve The construction of the burner with only the three fundamental parts mentioned above and the appropriate arrangement of the structural guide and fixing elements in each of them as will be described in detail below, offer for the burner which

  is the object of the present invention the additional advantage

  compared to burners known to be easy

  and quick to assemble after cleaning.

  The support bowl has the necessary means

  for fixing it by means of screws to the cooking appliance and remains below the work table

  through the openings from which more

  internal radial ribs with upper edges

  The higher steps, the more

  closer to the center of the room, allow the user to

  ger to center the body directly on the bowl-

  support by being guided in its orientation through the openings for passage of the spark plug and of the thermoelectric couple and an additional guide orifice

  arranged in the flat part, the body resting

  following stably on the surface of the lowest rungs of the ribs and fixing by interlocking a guide pin which emerges from one of the ribs

  of the support bowl in said guide hole.

  By means of two semi-circular notches

  90 fitted in the lower edge of its wall

  vertical ripherique one on each side of the cavity associated with the thermoelectric couple, the head fits

  precisely with the body by superimposing these

  sizes on two elongated projections of the body and the body with the same semi-circular profile, interlocking which is easily carried out at the first attempt thanks to the prior orientation provided by the cavities of the vertical wall of the head associated with the candle and the

thermoelectric couple.

  According to another of the characteristics of the invention, provision has been made for the enclosure associated with the ignition in the periphery of the burner, which houses the spark plug, to form in the burner between the head and the

  body but so as not to affect the main flame

  cipal; to this end, the cavity is semi-circular and has only been arranged in the thinnest part of

  the annular wall distributing the pilot flame

  leuse For the ignition of the gas, it was arranged according to this configuration that the spark springs between

  the electrode and the outer edge of a horizontal section

  zontale which delimits the enclosure from above, section of the annular wall of the enlarged head above

this enclosure.

  The perforation arranged in the body for

  the passage of the candle is located at such a distance

  the central axis it reaches the peripheral projecting edge of the body to the point of creating an air opening in the enclosure while conditioning the jump of the spark towards the edge in question in the head of the burner.

  The enclosure associated with the flame detector

  which houses the thermoelectric couple, is formed in

  the burner offered by means of a semi-cavity

  circular arranged throughout the annular wall of

  the head, which therefore affects the two flames, the main

  pale and that of pilot light, a thinning of the e-

  intermediate thickness being however provided for fa-

  promote combustion while allowing cooling

  thermoelectric torque faster after extinction, as happened with the walls

  thick of the embodiment described above.

  For positioning the body on the cu-

  support plate and to separate the two parts and thus create the space necessary for the entry of primary air, provision has also been made to replace the internal radial ribs, as mentioned above, of having on the horizontal peripheral platform of the support bowl, four axial projecting fins, one per quadrant, the

  fuel mixture thus being released from ob-

stacles for its cleaning.

  The invention will be explained by the description

  tion using the drawings in which: Figure 1 shows the entire burner mounted in a vertical section through the diameter which

  unites the spark plug and thermocouple housings

  electric, FIG. 2 is a top plan view of the burner body, FIG. 3 is a top plan view of the burner support bowl,

  Figure 4 is a section of the bowl-

  support along the plane AA of FIG. 3, showing the detail of the fitting with the body, FIG. 5 is a plan view of the burner head showing the sectioned peripheral profile, FIG. 6 shows a section of the following head the plane BB of FIG. 5, FIG. 7 shows the assembly of the burner mounted, in a vertical section similar to that

  of Figure 1, but according to an alternative embodiment

  tion which includes the variants mentioned above,

  Figure 7b is a vertical section through

  tial of the burner which passes through the flame detector, FIG. 8 shows the body of the burner in a vertical section which passes through the thermoelectric couple,

  Figure 8b is a vertical section through

  tielle of the body showing the perforation for the bou-

  gie, figure 9 shows the profile of the burner head, figure 10 is a horizontal section of

  the head at the orifices of the main flame

  the, Figure 11 is a horizontal section of

  the head at the pilot flame orifices

  Figure 12 shows the burner bowl seen from above, Figure 13 is a vertical section of the support bowl which passes through the fixing hole of

  the candle and by a separating fin.

Description of an example

  A preferred embodiment of the gas burner 1

  which is mentioned above and as it is my-

  very vertical section in Figure 1 includes essen-

  tial a support bowl 2, a body 3 and a head 4 with the incorporation of a spark plug 14

  and a thermoelectric torque 15 for safety.

  The support bowl 2 shown in the figures

  gures 3 and 4 constitutes the primary gas-air pre-mixing chamber 5 and supports the body in a guided manner It is structurally provided with several

  internal radial ribs 37 of uniform thickness

  angularly distributed form which start from the internal face of the side wall 38 and have a limited radial length to allow the housing of the hollow central member 7 of the body which protrudes above the surface 6 for fixing the support-bowl; this

  the latter has a rung on its upper edge

  nement in height, where the high rungs 39, closer to the central axis of the part, allow a first centering of the body on the support bowl and the lower rungs 40, which occupy most of the radial length rib,

  allow a stable support of the body while separating it

  rant of the tray of the upper part of the kitchen

  nière to delimit the space 41 of entry of the external primary air in the burner At least one of the radial ribs 39 of the bowl-support present

  on the lower rung a magnification 42 with circular section

  strip centered with the axis of the rib and with a diameter slightly greater than the thickness of the rib, which extends above its edge, this extension constituting a stud 43 mm which is entirely housed

  in the corresponding guide hole 34 of the body.

  The support bowl 2 has on its bottom

  two gas inlet conduits prepared for the con-

  connection of the piping of the cooking appliance,

  inlet lines converging on the prior passage 45 of the injector, a first conduit 46 with vertical axis

  intended for the connection of gas in the appliances

  and a second duct 47 with axis slightly inclined upwards with the side socket intended

with extra-flat stoves.

  The body 3 with a surface of revolution as indicated in FIGS. 1 and 2 comprises a hollow central member 7 which constitutes the drawing of the pre-mixture and a part 8 in the form of a disc whose periphery has a projecting edge 29 upwards. triangular section with the internal side cut out, edge o a channel 30 has been made by emptying the arc portion

  facing the hole 31 for passage of the thermo-torque

  electric to create an opening for the entry of outside air into the enclosure 21 which houses the tip of the thermoelectric couple The body is characterized

  by two reliefs 33 on the upper face, one of each

  side of the couple enclosure opening channel

  thermoelectric, these reliefs being elongated, dry-

  semicircular upwards and starting from the internal face of the peripheral projecting edge 29, they

  allow the nesting of the head; the body presented

  the arrangement of the guide hole 34 on its

  flat part for its nesting on the bowl-

support.

  The head 4 constructed in a single circular piece

  ring, according to Figures 5 and 6, constitutes at the same time the cover 10 which forms, with the body, the expansion chamber 9 of the burner and the flame distributor through a vertical annular wall 11

  provided with two formations of cor- rect outlet openings

  corresponding to the main flame 28 and the flame of

  pilot light 24, annular wall II which has two ca-

  turned outwards and form, with the body 3, the corresponding enclosures 20, 21 where the

  active tips 16, 17 of the spark plug and of the torque

  moelectric, cavities including internal partitions

  have special exit ports

  required for each of the devices The partition 22 of the cavity 28 corresponding to the candle having a shape

  semi-circular is provided with a single outlet orifice

  tie 23 and at an intermediate height between the two he orifice formations; the internal partition 25 of the cavity corresponding to the thermoelectric couple being straight, it is provided with two contiguous orifices 26 with a diameter larger than the orifices of the pilot flame which are situated at an intermediate height between the two formations of orifices; The dividers

  side 28 of the cavity associated with the thermo-torque

  electric are straight and diverging outwards

  to facilitate the cooling of the thermo-torque

  electric The two notches 35 with semi-profile

  circular arranged in the lower edge of the pa-

  ring king 11 lie one on each side of the

  cavity 22 associated with the thermoelectric couple.

  Another substantial characteristic of

  the head, it is a ridge 35 downwards with a truncated profile

  conical, under the cover of enclosure 20 of the

  spark plug and coaxial with respect to this device 14.

  According to the variant shown

  in FIGS. 7 and 7b, the burner 50 comprising the same

  my three fundamental parts of the burner described above, the one represented by FIGS. 1 to 6,

  i.e. a head 70, a body 60 and a bowl-

  support 90, and having the same configuration as regards their essential characteristics,

  the enclosure 51 of the candle 54 and the enclosure 52 of the neck

  full thermoelectric disposed between the head 70 and the body 60, so as not to affect the uniformity of

  the main flame over the extent of its cir-

  circular and located opposite one another in embrace-

  sant an arc lower than the quadrant so that the spark plug and the thermoelectric couple are alternately

  visible or not visible to the user.

  With regard to the burner head, according to FIGS. 9 to 11, the enclosure 51 associated with the spark plug 54 (FIG. 7) does not affect the formation of the orifices 73 of the main flame because the semi-circular cavity 80 is formed only in the thin part 74 of the annular wall 83; in the opening of the enclosure to the outside, there is a perforation 61 (FIG. 8) coaxial with

  the cavity formed in the body, with the dimensions cons-

  ideally wide for the passage of the candle, so as to affect the projecting edge 67 of the

  body and that spark 55 can optional-

be seen by the user.

  For the ignition of the gas, it has been arranged that the spark 55 directly ignites the gas which occupies the ignition chamber 51 and that from here the flame spreads to the gas housed in the intermediate 57 for distribution of the pilot flame According to FIG. 10, a magnification 79 of the thickness of the annular wall 8 above the cavity 80 which houses the electrode, allows a horizontal section delimiting the enclosure 51 and providing, in addition, an edge 82

  protruding blocking the way with spark.

  The enclosure 52 associated with the thermoelectric couple

  stick 56 (Figure 7 b) is formed by a cavity 81 se-

  semicircular created on both sides 71, 74 of the annular wall 83 and therefore affects the two formations 73, 75 of flame orifices, but the average thickness has

  been thinned to favor the cooling of the

  full thermoelectric; around orifices 77, 78 at a

  level of the wall, for heating the thermo-torque

  electrical, we maintain a large wall thickness

equal for both.

  The thermoelectric couple 56 crosses the body through a perforation 65 adjusted to its diameter, the center of which is also distant from the center of the burner.

  as the perforation 61 for the candle.

  For centering and supporting the body 60 (fi-

  gure 8) on the support bowl (FIGS. 12 and 13) and the separation between the two parts which give rise to the inlet space for the primary air, the horizontal peripheral platform 95 of the support bowl, four fins 91, 93 projecting axially, the chamber 98 for mixing gas and air in the support bowl being thus cleared of any obstacle for its cleaning In a complementary manner, for centering the body and at a distance from the center of the burner equal to that of the fins 93, care has been taken

  a face 66 slightly inclined on the circular portion

  the surface of the lower surface of the disc 69 of the body.

  The angular positioning of the body relative to the support bowl is obtained by virtue of the fact that one of the four fins with a non-planar profile is different from the three.

  others, is provided with a protuberance 92 which fits

  te under a relief 68 formed radially on the surface

  horizontal plane of disc 69 of the body.

  To obtain a more regular gas-air mixture

  link in the expansion chamber 56, on the inner duct of the cylindrical central member 62 of the body, a staggered diameter has been arranged which increases the turbulence of the mixture as its

section is reduced.

Claims (8)

R E V E N D I C A T I 0 N S   1) Extra-flat gas burner with safety device, particularly intended for appliances with   cooking for domestic use equipped with a candle   lighting and a thermoelectric couple as a safety device, comprising a support bowl (2), a body (3) and a head (4), o the support bowl   constitutes the pre-mixing chamber (5) au-   below the cooker working table, where the body (3) comprises a central member (7) which constitutes   the drawing of the premix and a part (8) hori-   outwardly divergent zontally forms the chamber (9) for expanding the mixture, where the head (4), constructed in a single circular piece, constitutes at the same time the cover (10) of the burner and the flame distributor through an annular wall (11) with two   formation of outlet openings at different heights   annuities, where the spark plug (14) and the thermoelectric couple   that (15) are fixed to the support bowl and whose active points (16, 17) are housed in diametrically opposite cavities of the head, characterized in that the annular wall (11) of the head has two cavities ( 18, 19) outwards forming, with the body (3), the enclosures (20, 21) o are housed   the active tips of the spark plug and the thermo-torque   electric and o the concave enclosure (20) of the spark plug   formed by a semi-shaped front partition (22)   circular is provided with a special opening for   ignition, the concave shape of the thermoelectric couple   that being formed by a straight front partition (25) and two straight and divergent lateral closions (28)   outwards, the front partition (25) being for   view of two contiguous orifices (26) which, having a diameter   meter larger than that of the pilot flame orifices, allow controlled heating of the   sensitive tip (17) of the thermoelectric torque.   2) Extra-flat gas burner with safety device according to claim 1, including the body (3)   has a projecting edge (29) on the periphery,   characterized by the fact that this edge has a channel (30) hollowed out in the portion of arc opposite to the orifice (31) of the thermoelectric couple which allows more large outside air access.   3) Extra-flat gas burner with safety device according to claim 1, characterized in that the body (3) has two projections (33)   elongated on the upper side which allow the   limping of the head and the fact that said body   (3) is provided with an orifice (34) allowing it to be guided   ge and its posterior nesting on the bowl- support (2).   4) Extra-flat gas burner with safety device according to claim 1, characterized in that the head has, under the cover of the enclosure (20) associated with the spark plug, a crest (35) downwards, coaxial with respect to said spark plug (14) to form the electric ignition arc and by the fact that, on the lower edge of the annular wall (11), two semicircular recesses (35) have been arranged for nesting with the body.   ) Extra-flat gas burner with   safety according to claim 1, where the bowl   support (2) is structurally provided with several   internal radial ribs (37) distributed angularly   lairement, characterized in that these ribs (37) protrude above the fixing surface of this support-bowl and that their upper edges have a stepped profile on their upper edge, with   a high step (39), facilitating prior centering   ble of the body on the support bowl and a low rung (40) allowing the final stable support of the body and its separation from the tray of the stove delimiting   the inlet (41) of the primary outside air into the burner   their. 6) Extra-flat gas burner with   safety according to claims 1 to 5, characterized   by the fact that at least one of the radial ribs of the support bowl present on the upper edge of   the rib a boss (42) of thick cross-section   cular centered relative to the axis of the rib, which appears above its edge like a tenon   (43) to fit entirely in the guide hole dage (34) corresponding to the body.   7) Extra-flat gas burner with safety device according to claim 1, characterized in that the support bowl (2) has, on its bottom, two gas inlet conduits intended for the   connection of each of the different cooking appliances   ner, which converge on the prior passage (45) to the premixing chamber, a first conduit (46)   with vertical axis and a second conduit (47) with light axis-   inclined upwards with the side grip.   8) Extra-flat gas burner with safety device according to claim 1, characterized in that, in a variant of the embodiment of   the invention, the cavities (80, 81) which form the   belts (51, 52) for the spark plug and for the thermoelectric couple flame detector between the head (70) and the body (60) are semicircular, the enclosure (51) corresponding to the ignition only   by means of the thinnest part (74) or distributed   flame of the pilot flame of the wall (83) annu-   air opening to the outside through a perforation   tion (61) coaxial peripheral arranged in the body (60) for the passage of the candle (54), perforation at   considerably large dimensions compared to that   the latter, which affects the peripheral protruding edge (67) of the body (60), so that the spark (55) is visible   from the outside of the burner, and the enclosure (52) cor-   responding to the detection of the flame formed by the two parts (71, 74) of the annular wall (83), the two enclosures being angularly separated one of the other by less than a quadrant.   9) Extra-flat gas burner with safety device according to claim 8, characterized in that the ignition chamber (51) is delimited, above the spark plug, by a horizontal section of the wall (83 ) annular which has been magnified above the enclosure (51), magnification (79) which provides an edge (82) projecting to the periphery through which closes the path of the spark (55) of the spark plug during ignition.   ) Extra-flat gas burner with safety device according to claim 8, characterized in that the flame detection enclosure (52) is formed by cavities (81) arranged in the two parts (71, 74) of the annular flame-distributing wall, cavities with an irregular wall thickness which is determined by the flame orifices (77, 78)   individuals heating the thermoelectric couple.   11) Extra-flat gas burner with   safety according to claims 1 and 8, where the   body (60) has a cylindrical central member conducting the fuel mixture, characterized in that the inner duct of the cylindrical central member (62) of the body has a staggered diameter. 12) Extra-flat gas burner with   safety according to claims 1 and 8, where the   body (60) is located on the support bowl (90) with   an intermediate space for the entry of primary air   re and o inside the support bowl (90) cons-   titues the fuel mixing chamber, characterized by the fact that, for centering and supporting the body, four fins (91, 93) have been arranged on the peripheral platform (95) axial projections at a height determined by this space and, for its angular positioning, one of these fins (93) is provided with a protuberance (92) which fits under   a relief (68) of the disc (69) of the body (60).