| JP2011220653 | BURNER FOR GAS COOKING STOVE, AND GAS COOKING STOVE |
| JP09159119 | GAS BURNER |
| JP2003279008 | BURNER |
PAESANI, Carlo (Via Direttissima del Conero 29, Camerano, I-60021, IT)
| C LA I MS 1. A gas burner with multiple flame rings, comprising an injector holder piece (2), a flame divider (4) having an outer portion (26) of overall annular shape and an inner portion (28) of overall circular shape, and means (6) for upperly closing said outer and inner portions, characterised in that: - said injector holder piece (2) carries, applied thereto, at least two injectors (20, 20') of substantially vertical axis positioned in a substantially diametrical plane of the burner, - said flame divider (4) comprises at least two substantially vertical conduits (46, 46') facing the two injectors (20, 20') of the injector holder (2) and opening upperly into a horizontal venturi effect chamber, bounded upperly by said closure means (6), - the region downstream of said horizontal vertical effect chamber is connected in a fluidic manner to the inner portion (28) of said flame divider (4), via two channels (36, 60). 2. A burner as claimed in claim 1, characterised in that applied to the injector holder 2 there are two injectors (20) positioned on the base of two upperly open and laterally closed cups (8) which with their lateral wall surround the vertical conduit (46) facing the corresponding injector (20). 3. A burner as claimed in one or more of the preceding claims, characterised in that the lateral wall of each cup (8) extends upperly in the form of a rim (16) beyond the sheet metal of the cooking hob (14) and receives, resting thereon, a corresponding profiled projection (22) jutting lowerly from the flame divider (4) and partially interrupted to form an aperture providing access to the interior of said cup for the primary air drawn in from above said cooking hob. 4. A burner as claimed in claim 3, characterised in that the flame divider (4) resting by its profiled projections (22) on the upper rim (16) of each cup (8) maintains said flame divider raised from the sheet metal of the cooking hob (14) by an amount sufficient to determine therebetween two passages for the secondary air feeding the inner portion (28) of said flame divider (4). 5. A b u rn e r a s cl a i m ed i n o n e o r m o re of th e p reced i n g cl a i m s , characterised in that the inner portion (28) of the flame divider (4) is of overall circular shape, the outer portion (26) being of overall annular shape comprising two widenings at which said horizontal venturi effect chambers are provided. 6. A burner as claimed in claim 5, characterised in that the outer portion (26) of the flame d ivider (4) presents an outer rim (30) extend ing along a circumference, and an inner rim (32) a certain part of which extends along a circumference internally concentric with the preceding circumference while the remaining part forms two re-entrant regions corresponding with the widenings of said outer portion. 7. A burner as claimed in claim 5, characterised in that the inner portion (28) of the flame divider (4) is bounded by a rim (34) which is of circular shape with the exception of parts connected to the outer rim (32) of the outer annular portion (26) of said flame divider. 8. A burner as claimed in claim 7, characterised in that the connection parts between the rim (34) of the inner portion (28) of the flame divider (4) and the outer rim (32) of its outer portion (26) define radial channels (36) providing fluidic connection between the radial venturi effect chambers and said inner portion (28). 9. A burner as claimed in claim 8, characterised in that said closure means (6) consist of a cover comprising an annular outer portion (52) for closing the outer annular portion (26) of the flame divider (4), a circular inner portion (54) for closing its circular inner portion (28), and two radial profiled portions (56) connecting together said outer portion (52) and said inner portion (54) and for upperly closing said radial channels (36). 10. A burner as claimed in one or more of the preceding claims, characterised by providing, in that portion of the injector holder (2) which connects the two cups (8) together, two channels (60) connecting each horizontal venturi effect chamber to the base of the inner portion (28) of said flame divider (4). 11. A burner as claimed in one or more of the preceding claims, characterised by applying, to the injector holder (2), three injectors (20, 20') positioned on the base of three cups (8, 8') and substantially aligned in the diametrical plane of the burner. 12. A burner as claimed in one or more of the preceding claims, characterised in that the cups (8, 8') are provided with access apertures for the primary air drawn in from above the cooking hob. |
The present invention relates to a gas burner with multiple flame rings.
Single control gas burners with multiple concentric flame rings are known, i.e. burners in which the gas feed is controlled by a single tap. These general ly com prise an injector holder cup, a flame d ivider resting on the injector holder cup and formed from two parts joined together to form an inner central portion and an outer annular portion, an annular cover which closes the annular portion of the flame divider, and a discoidal cover which closes the central portion of the flame divider.
Hence known gas burners with multiple concentric rings are formed from a total of five elements assembled together.
One of these known bu rners is descri bed for example in EP-B1 - 0797048.
An object of the invention is to provide a gas bu rner of m u ltipl e concentric ring type in which the number of components is reduced.
Another object of the invention is to provide a gas burner of multiple concentric ring type which is of limited overall height, such as to be able to be mounted on traditional built-in cooking hobs.
Another object of the invention is to provide a gas burner of multiple concentric ring type in wh ich the primary air is d rawn in from above the cooking hob, in order to prevent streaming, i.e. flame disturbance on sudden opening of the oven door or of a furniture item positioned below the cooking hob.
These and other objects wh ich will be apparent from the ensu ing description are attained accord ing to the invention by a gas bu rn er with multiple concentric rings as described in claim 1 . The present invention is further clarified hereinafter by means of some preferred embodiments thereof described with reference to the accompanying drawings, in which:
Figure 1 is an exploded perspective view of a first embodiment of the burner according to the invention, seen from above,
Figure 2 is an exploded perspective view thereof seen from below,
Figure 3 is a perspective view thereof in its assembled state, mounted on a cooking hob,
Figure 4 is a perspective view thereof shown in vertical section,
Figure 5 is a second embodiment thereof shown in the same view as Figure
4, and
Figure 6 shows a third embodiment thereof with three injectors.
As ca n be see n fro m t h e f ig u res , the burner of the invention comprises, in the embodiment shown in Figures 1 -4, three basic components consisting of the injector holder 2, the flame divider 4 and the cover 6.
The injector holder 2 is of essential ly elongated extension and is shaped to define two cups 8 connected together by two baffles 1 0. The two cups are closed lowerly and laterally and are open at their top, where the lateral wall is provided with an outwardly jutting flange 1 2 for resting against the underside of the sheet metal of a cooking hob 14, to which the burner is fixed by screws.
The lateral wall of each cup 8 extends upperly beyond the flange 12 to form a rim 1 6 emerg ing from the cooking hob 1 4 and acting as the support element for the flame divider 4.
The injector holder 2 also comprises a gas feed conduit 18; it extends horizontally below the base of the two cups 8, it is open at one end for gas entry and communicates with two injectors 20 screwed centrally to the base of the cups.
The flame divider 4 rests on the injector holder 2 such that two of its downwardly jutting profiled projections 22 rest on the upper rims 16 of the two cu ps 8. These profi l ed proj ections 22 do not extend along the enti re extension of the corresponding upper rims 1 6, but only along its two lateral portions and along its inner portion , such as to define between the flame divider 4 and the injector holder 2 two apertures for access of the primary air originating from above the cooking hob 14 into the two cups 8.
The flame divider 4 is centred about the injector holder 2 by projections 24, which extend downwards from the flame divider 2 and adhere via their outer vertical edge to the inner surface of the lateral wall of the two cups 8.
The flame divider 4 comprises an outer portion 26 of overall annular shape and an inner portion 28 of overall circular shape.
More particularly, the outer portion 26 presents an outer rim 30 which extends along a circumference, and an inner rim 32, of which a certain part extends along a circumference concentric with that of the outer rim 30, then it curves inwards to connect to the circular rim 34 of the inner portion 28. In this manner two substantially rad ial channels 36 are obtained provid ing flu idic connection between the inner circular portion 28 and the outer annular portion 26 of the flame divider 4. Hence these two portions are bounded by a single continuous rim, which comprises along its entire extension, with the exception of the parts relative to the two radial channels 26, a plurality of main ports 38 and secondary ports 40, which on the rim 30 form the outer ring of outwardly directed flames, on the rim 32 form the intermediate ring of inwardly directed flames, and on the rim 34 form the inner ring of outwardly directed flames.
The two rims bounding the radial channels 36 also present secondary apertu res 42 , th e pu rpose of wh ich is to tra nsm it the fla mes from th e intermediate ring to the inner ring.
In addition, in the outer portion 26 of the flame divider 4, two channels 43 are positioned provided with two small ports 44 for inter-ignition between the flames of the outer ring and those of the intermediate ring and inner ring.
The flame divider 4 also comprises two vertical conduits 46 which at their lower end face the two injectors 20 and open upperly at projections 48 wh ich lowerly define two venture effect chambers bounded upperly by the cover 6, which rests on the flame divider 4 at four centring pegs 50 provided therein.
When the flame d ivider 4 rests via its profiled projections 22 on the upper rims 16 of the two cups 8, it is maintained spaced from the sheet metal of the cooking hob 14 by a distance such as to determine passages therewith for the secondary air intended for the inner portion 28 of the flame divider.
The cover 6 is formed in one piece and comprises an annular outer portion 52, a discoidal inner portion 54 and two profiled rad ial connection portions 56.
The burner of this embodiment operates in the following manner:
The gas entering from the conduit 18 leaves from the injectors 20 and enters the two vertical cond u its 46 of the flame d ivider 4, to entra in the primary air drawn in from above the cooking hob 1 4 through the apertures defined by the outer part of the profiled projection 22 of each cup 8 and the overlying flame divider, in accordance with the path indicated by the arrows 58 in Figure 4.
The flow of gas and primary air wh ich begins to m ix in each of the vertical conduits 46 completes its mixing in the corresponding radial venturi chamber defined lowerly by the surface of the projection 48 and upperly by the cover 6.
The m ixtu re obta ined i n th is man ner then propagates along the annular portion 26 of the flame divider 4 to feed the two rings of outer and intermediate flames thereof, then further propagates along the two rad ial conduits 36 to feed the central ring of flames of the inner portion 28.
From the aforegoing it is apparent that the burner of the invention is much more advantageous than traditional multi-flame ring burners, and in particular:
- it is formed from only three pieces, hence as the flame divider is of one- p iece d ie-cast construction without machining, it is of simple and economical manufacture,
- the cover, even though intended for a three flame ring burner, is also formed in one piece, again making the burner manufacture simple and economical,
- because of the use of radial venturi mixing chambers, it is of small vertical height and easily installed in normal cooking hobs. The fact of having two mixing chambers means that a power can be developed wh ich is much higher than traditional burners with a single radial venturi mixing chamber,
- finally, as the primary air is drawn in from above the cooking hob, it is virtually insensitive to streaming. In the embodiment illustrated in Figure 5, the gas/primary air mixture of the burner of the invention generated by the two radial venturi chambers is conveyed into the inner central portion 28 of the flame divider 4 not through rad ial ch an nels bou nded by the fla me d ivider and the cover, as i n the preceding embodiment, but by two radial channels 60 bounded by the flame divider 4 and the injector holder 2. For th is purpose the injector holder 2 is provided, in the connection portion between the two cups 8, with two radial channels 60 which connect the two radial venturi mixing chambers to the inner portion 28 of the flame d ivider 4, wh ich is also provided with baffles 62 for upperly closing said channels 60.
In th is embodiment the cover 6, the purpose of which is no longer to upperly bound the radial channels connecting the two mixing chambers to the inner portion 28 of the flame divider 4, can be formed in two separate parts, of which the outer part is of approximately annular shape and the inner part is of discoidal shape.
Th e em bod i m ent shown i n F ig u re 6 d iffers from the preced i ng embodiments by the addition, to the two cups 8 provided on their base with corresponding injectors, of a third central cup 8' provided on its base with a third injector 20', also communicating with the same gas feed conduit 18.
In this case the inner portion 28 of the flame divider 4 communicates with the cup 8' via its own vertical conduit 46', through which the gas/primary air mixture is fed.
The flame divider 4 rests only partly on the underlying injector holder 2, such as to define access apertures for the primary air originating from above the cooking hob.