Atmospheric gas burner with sequential and superminimum device

Abstract

Atmospheric gas burner, for use in oven cooking chambers, and comprising an hollow and prolonged body provided with a first portion able of lodging a main burner and a second portion able of lodging a secondary burner (mini-burner) said two portions being hermetically separated by a wall placed inside said hollow body; on the outer surface of said hollow body a third assembly of cross-lighting ports is placed, wherein said cross-lighting ports extend in correspondence both of said first portion and on said second portion, and preferably are alined each other, a deflecting element is placed outside said hollow prolonged body, which is close and in front of said cross-lighting ports, an is also able of allowing the flame propagation among said cross-lighting holes, and between a fraction of these and said secondary holes. Said deflecting element is placed and extended in such a way not to cover either said main holes and said secondary holes

Description

This invention deals with a gas atmospheric burner with sequential operating and superminimum device which can be usable in particular for cooking ovens for domestic and professional use and, at the same time, for defrosting systems on frozen or deep-frozen food. It consists of a known main burner (1) formed by a Venturi duct (10) and an air-gas mixing chamber (2) supplying the burner by two rows of main ports (3) arranged at 180° laterally and a group of ports (4) arranged at 180° that are used for supplying the mini burner (6) which is the main matter of this invention. Cross-lighting ports (11), placed under the stabilisation deflector (12), specially shown in FIGS. 1 and 3, are used to transmit the flames automatically from the main burner to the mini burner and they light at the same time the main ports (3) and the group of ports (4). At the opposite side of main burner inlet there is the inlet for mini burner consisting of a Venturi duct (7) with an air-gas mixing chamber (13) supplying the mini burner which can be of suitable dimensions depending on cap displacement (8). Defrosting flames (Fs) supplied by ports (4) are used to obtain temperatures suitable for frozen or deep-frozen food defrosting (from 40° to 90°). Main flames (Fp), produced by main ports (3) are instead used for normal food cooking (from 120° to 300°). The thermocouple (9) positioned at an adequate distance from mini burner controls the presence of the flame and transmit the signal to a control unit operating on the temperature system set by the user.

There are several types of atmospheric gas burners, designed and produced for oven cooking. But these burners aren't usable for defrosting systems on frozen or deep-frozen food because they are not equipped with the superminimun device. We know other appliances suitable to defrosting purposes as electric microwave ovens.

However these appliances have two difficulties: they operate by electric power with high costs and their cooking compartments volumes are very little. We remember that the volume of the oven in a domestic range is about 5 times greater than a standard microwave oven volume. Therefore benefits with this new invention are evident and for everybody using the oven of cooking ranges.

The purpose of this invention is to cook and defrost by mean of an only gas burner with sequential system at very low temperatures and this can be achieved by the particular and specific design allowing to supply two burners in a perfectly stoichiometric ratio using all kinds of gas mixtures, getting high performances and efficiencies with the same dimensions, with a “range” of temperatures from 40° to 300° and also keeping constant the temperatures values that have been set previously.

For a full understanding of features and benefits that could be obtained by this new gas burner, being itself the object of this invention, the same burner, just as a non limiting example and in a specific form, is represented here in succession and in details according to the following drawings where:

FIG. 1 shows a longitudinal and partially sectioned side view of the gas burner according to the invention,

FIG. 2 shows a perspective of a partially sectioned view of the gas burner of FIG. 1,

FIG. 3 shows a view corresponding to the one of FIG. 1, but with a main component of the gas burner disassembled from the main body of it.

In these figures common details and parts are reported with the same references.

Basically, the purpose of the atmospheric gas burner with sequential operating and superminimum device is to be particularly usable for cooking ovens for household and commercial use; this burner consists basically of a main burner (1) with a mixing chamber (2) supplying a Venturi duct (10) by an air-gas combustible mixture which feeds the main ports (3) creating flames (Fp) and cross-lighting holes (11) serving to transmit the flame from the main burner to the mini burner and vice versa.

As illustrated on FIG. 1, the burner group consists of two opposite gas inlets, the former inlet supplying the main burner the latter inlet supplying the little burner or mini burner. The whole assembly is easily producible by common machine tools and industrial processing lines. However burner group will be synthetically described for a full understanding of the whole burner assembly and operating. As FIG. 1 shows, burner assembly (1) consists of a Venturi duct (10) whose external end, the one with minor diameter, is supplied with a suitable air/gas mixture produced and admitted by an opportune group (2) called “mixing chamber”; anyway its construction and operating, though they are well-known, will be herein described for clarity. According to fig.1, it is clear that the mixing chamber (2) consists of an injector (not shown here) installed at its extremity. This injector is arranged in a coaxial way as to the Venturi duct (10) and inside the air-gas mixing chamber. When the injector is supplied with gas, it emits by the outlet hole, in the direction of Venturi duct (10), a relative gas jet which, as it's well-known, drags a suitable rate of air called “primary air” and mixes with the air creating a combustible air-gas mixture: by the opposite extremity of Venturi duct (10), the extremity having the bigger diameter, the air-gas mixture pours out supplying the main burner intended for cooking and cross-lighting holes (11) which, in case of defrosting mode, light ports (4) igniting defrosting flames (Fs).

At the opposite extremity of the main burner (1) there is the air-gas mixing chamber (13) where the injector (not shown) is placed at the extremity; the injector let the mixture flow coaxial as regards the duct (7) getting into the chamber of the mini burner and supplying the flames intended for defrosting (Fs). In FIG. 1 a flame detector device is shown (9); it works by a temperature control system and puts in operation the main burner (1) or the defrosting burner according to the temperature set by the user, or the two burners together.

FIG. 2 shows a simplified sectional and perspective view of defrosting burner.

In conclusion, this sequential burner, object of our invention, allows not only to avoid the above mentioned inconveniences of common defrosting appliances, but also to get considerable benefits.

In fact this burner allows to get a large range of temperatures inside the oven varying from 40° to 300°, able to cook every kind of food as vegetables, sweets etc . . . , or to defrost at very low temperatures vegetables, white meat, etc. . . . To this day this versatility is unavailable in the market. In reality by mean of an only burner and two gas inlets we can get either cooking mode or defrosting mode.

Of course different changes could be introduced to this burner, object of our invention, without leaving this described domain and, according to enclosed drawings, the following claims and then the domain of our private industrial patent.

Claims

1. Atmospheric gas burner, particularly for the use in the cooking chambers of household or commercial (catering) cooking ovens, and comprising at least an hollow and prolonged body, characterized in to that said hollow prolonged body comprises a first portion able of lodging a main burner (1) and a second portion able of lodging a secondary burner (mini-burner) (6), said two portions being hermetically separated by a wall (8) placed inside said hollow body.

2. Atmospheric gas burner according to claim 1, characterized in that on the outer surface of said hollow body

a first assembly with main holes (3), associated to said first portion, said main holes being able of allowing the emission of respective gas jets related to said main burner (1), and

a second assembly with secondary holes (4), associated to said second portion, said secondary holes being able of allowing the emission of respective gas jets related to said secondary burner (6), are placed.

3. Atmospheric gas burner according to claim 1, characterized in that said main and secondary burners (1, 6) are associated, on their opposite sides of said hollow prolonged body,

to two respective mixing chambers (2, 13) able of supply with two respective gas flows,

respective Venturi ducts (10, 7), which penetrate into said respectively main burner (1) and said secondary burner (6).

4. Atmospheric gas burner according to claim 3, characterized in that said Venturi duct (7), associated to said secondary burner (6), is implemented through a conduit which is substantially outside of said hollow prolonged body.

5. Atmospheric gas burner according claim 2, characterized in that:

said main holes (3) are placed successively along two straight lines which stretch parallel each other on two opposite sides of said first portion,

said secondary holes (4) are placed successively along two straight lines which stretch parallel each other on two opposite sides of said second portion.

6. Atmospheric burner according to claim 1, characterized in that

on the outer surface of said hollow body a third assembly of cross-lighting ports (11) is placed,

said cross-lighting ports extend in correspondence both of said first portion and on said second portion, and preferably are lined each other,

a deflecting element (12) is placed outside said hollow prolonged body, and which is close and in front of said cross-lighting ports,

a gap is implemented between said deflecting element and the surface of said prolonged hollow body, whose thickness is able of allowing the flame propagation among said cross-lighting holes, and between a fraction of these and said secondary holes (4).

7. Atmospheric burner according to claim 6, characterized in that said deflector (12) is placed and extended in such a way not to cover either said main holes (3) and said secondary holes (4).

8. Atmospheric burner according to claim 1, characterized in that it is provided with a temperature sensor (9) lodged inside said second portion.

9. Cooking oven comprising a cooking chamber and a gas burner contained or associated to said cooking chamber, characterized in that said gas burner is carried out according to claim 1.

10. Cooking oven according to claim 9, characterized in that it is provided with control means able of allowing the gas selectively and independently flowing both to the main burner (1) and to the secondary burner (mini-burner) (6).