EP2839214A1

EP2839214A1 - Combustion systems for cooking equipment burners

Info

Publication number: EP2839214A1
Application number: EP12820850.1A
Authority: EP
Inventors: Marcos Raphael Da Silva; Henrique Cesar De Gaspari
Original assignee: Whirlpool SA
Current assignee: Whirlpool SA
Priority date: 2011-12-20
Filing date: 2012-12-18
Publication date: 2015-02-25
Also published as: MX2014007610A; US20150037741A1; WO2013106892A1; BRPI1105370A2

Abstract

The present invention refers to a combustion system applied in cooking equipments, which comprises technical features capable of enhancing heat exchange efficiency and capacity of cooking equipments through a turbulent combustion regime process. Preferably, the combustion system in accordance with the present invention comprises a fuel feed duct (1) connected to a cooking equipment burner (2) by means of an intermittent mechanism (3) for the purpose of releasing and blocking the fuel flow coming from said feed duct (1) such that an ignition element (4) causes a fuel turbulent combustion in said burner (2).

Description

"CO BUSTION SYSTEMS FOR COOKING EQUIPMENT BURNERS"

Field of the Invention

The present invention refers to a combustion system for cooking equipment burners, particularly for household stoves. More specifically, said combustion system, object of the present invention, comprises new features capable of increasing efficiency and capacity of heat exchange in cooking equipments by means of a turbulent regime of the process and combustion.

Background of the Invention

In accordance with the state of the art, it is common knowledge that cooking equipments are provided with a cooking table over which burners responsible for producing flame and heating the cooking utensils (pans, dishes, and the like) are distributed. In this regard, it can be observed that manufacturers of these types of equipment are constantly searching for developments and solutions, which will, in some way, lead to technical and functional benefits, mainly related to efficiency, safety and practicality.

Thus, aiming at achieving these results and results, several models of cooking equipments provided with burners comprising complementary devices and mechanisms which are capable of increasing safety or efficiency are known from the state of the art. For example, US Patent 6,322,352 refers to a gas combustion system provided with means for shutting off the gas supply upon failure in igniting a burner. As can be noted, said model known in the art only intends to improve safety of the cooking equipments by eliminating fuel leakage risks, wherein its functioning is conventional from the moment at which the burner is ignited. Therefore, it is important to point out that this state-of-the-art burner model does not lead to any improvement in the heat exchange efficiency.

Particularly, with regard to improvement in the efficiency of burners, reference should be made to US Patent 7,942,143 and JP 2005156087, which disclose burners provided with complementary devices and mechanisms intended to produce a flame and a heat flow with high heat capacity. More specifically, it should be noted that such models known in the art comprise a constructional arrangement of their components whose purpose is to provide barrier species disposed along the heat flow generated by the burner or in the flame vicinity. The objective of such models is to form an environment which allows for keeping the heat flow in the burner region, thereby trying to obtain heat efficiency in cooking equipments.

As can be inferred, such state-of-the-art models show a relatively complex configuration, requiring an arrangement comprising several complementary devices and mechanisms, which end up resulting in an increase in the costs of manufacturing and assembling of those cooking equipments.

Additionally, said cooking equipment models known in the art lead to a limitation related to fuel consumption once, in an attempt to obtain an improvement in heat exchange efficiency and capacity, they end up using means which would affect fuel consumption. Furthermore, such models require a continuous flame and, to this effect, there is an uninterrupted fuel flow for the proper functioning of the burners.

In a brief and concise form, it is verified that the current techniques of not disclose cooking equipments comprising a combustion system that would effectively reduce fuel consumption. And, such current techniques would also not provide an improvement in yield and efficiency in the heat exchange of burners.

By this way, it can be noted that, despite being functional up to now, these cooking equipments known in the art could be improved so as to increase the efficiency without significantly affecting manufacturing costs and assemblage due to a need for great adaptations and / or complex implementations.

Objects of the Invention

In view of the foregoing, one of the objects of the present invention is to provide a combustion system applied in cooking equipments, wherein said system is capable of simply and efficiently improving and / or minimizing the drawbacks and limitations concerning combustion systems already known in the art.

More particularly, another object of the present invention is to provide a combustion system applied in cooking equipment burners, comprising technical and functional features which enhance burner heat exchange efficiency.

The combustion system, object of the present invention, also intends to improve the fuel combustion process as well as to increase efficiency, or also, promote fuel consumption economy.

Summary of the Invention

Therefore, in order to accomplish the above-mentioned objects and technical effects, the present invention refers to a combustion system for cooking equipment burners, wherein said system comprises a fuel feed duct connected to said burner, said elements being connected by means of at least an intermittent mechanism that releases and blocks injection of fuel flow in order to generate a turbulent combustion by means of at least one ignition element.

In a preferred embodiment, said intermittent mechanism is electronic and comprises at least one valve actuated by electric / electronic signals sent by an electronic controller capable of controlling the amount of gas and the respective time intervals at which fuel is injected into the burner.

Alternatively, in another embodiment of the present invention, said intermittent mechanism is mechanical and comprises at least one valve actuated by a lever whose end is disposed at the fuel feed channel outlet in order to release and block fuel (or an air-fuel mix) flow in the burner combustion chamber. Preferably, in this embodiment, said valve is attached to said lever by means of at least one return element capable of forcing the lever to be repositioned in the closed position.

In a further preferred embodiment of the present invention, said combustion chamber can comprise at least one auxiliary air or air-fuel inlet at any ratio.

It should be pointed out that the combustion system, in accordance with the present invention, can be applied in burners with closed or opened configuration, that is, with opened or closed chamber.

It should also be clarified that said ignition element can be of any type with the provision that it is capable of promoting a burst in the combustion chamber at a suitable time. Preferably, it can be electric / electronic or even a small pilot flame fed by a parallel duct which is also fed by a main feed duct.

Brief Description of the Drawings

Fig. 1 schematically shows a combustion system in accordance with the present invention;

Fig. 2 schematically shows a combustion system in accordance with a first preferred embodiment of the present invention;

Fig. 3 schematically shows a combustion system in accordance with a second preferred embodiment of the present invention.

Detailed Description of the Invention

According to the above-mentioned schematic figures, some examples of possible embodiments of the present invention will be described in more details below for only exemplary, non-limitative purposes, since the present combustion system can be built with different aesthetic and dimensional characteristics without, however, entertaining from the desired scope of protection.

The combustion system, object of the present invention, mainly aims at providing an intermittent fuel flow to provide for a pulsed combustion, such as a pulsating combustor. More specifically, the combustion system, in accordance with the present invention, comprises a fuel (or air-fuel mix) feed duct 1 connected to a cooking equipment burner 2, wherein an intermittent mechanism 3 is disposed between said parts in order to release or block fuel (or air-fuel) flow coming from said feed duct 1 such that an ignition element 4 causes the fuel combustion in said burner 2 when the flow is released by said intermittent mechanism 3.

As seen from Fig. 1, the combustion system of the present invention is applied in a burner 2 whose purpose is to heat a cooking utensil 5 positioned in a grill or tripod 6. This heating is carried out by a flame coming from a combustion chamber operating in conjunction with a mechanism that intermittently supplies fuel and / or air-fuel mix at any ratio to said combustion chamber in order to generate a turbulent combustion regime, this being capable of increasing heat exchange efficiency once, as can be observed, heat transfer rates are directly proportional to the temperature difference existing between the media.

In a preferred embodiment of the present invention, said combustion system comprises an electronic intermittent mechanism 3 ', which is constituted by a valve actuated by electric / electronic signals, such as an electromagnetic valve. In this embodiment, as illustrated in Fig. 2, said intermittent mechanism 3 'is connected to an electronic controller 7, through which it is possible to regulate the amount of gas and time intervals of injecting fuel in the burner 2.

Fig. 3 shows an alternative embodiment of the combustion system in accordance with the present invention and comprises a mechanical intermittent mechanism 3 ". In this embodiment, said intermittent mechanism 3" comprises a valve 8 actuated by means of a lever 9 capable of releasing and blocking the fuel flow in the combustion chamber 10 of burner 2, within which an ignition element 4 is disposed in order to promote pulsed combustion as the fuel is injected.

More particularly, it should be mentioned that said lever 9 moves between a closed position and an opened position by virtue of the pressure variation within said combustion chamber 10. In other words, at the moment the burst caused by said ignition element 4 occurs the internai pressure is elevated thus causing said lever 9 to move to a closed position and at the same time a valve 8 is actuated at the moment in which the pressure inside the combustion chamber 10 becomes equalized, said lever 9 moving to the opened position, thus restarting the intermittent process of releasing and blocking the fuels by the feed duct 1.

Preferably, said valve is interconnected to lever 9 through a return element 12, such as a spring. Said return element 12 is responsible for forcing said lever 9 to return to a closed position when the pressure is being equalized within the combustion chamber.

The combustion system, in accordance with the present invention, can be applied in burners comprised of opened or closed combustion chambers, that is, with or without shield or flame diffuser before the grill or tripod.

Additionally, it should also be observed that said ignition element 4 can be of any type with the same provision that is capable of causing an intermittent burning at the time the fuel flow is released. Preferably, said ignition element is electric / electronic or, alternatively, it can be a small pilot flame fed by a parallel duct 11, as illustrated in Fig. 3.

Further, it is important to mention that the present combustion system preferably and advantageously consists of only two work stages, that is, totally closed and totally opened, this being due to the fact that, in accordance with the objects of the present invention, there is no direct interest in obtaining two intermediate work stages, that is, variation of the flame between low values and high values because under these conditions there would be periods of constant and non-turbulent functioning regimes. Logically, such a configuration is merely preferential, which does not give rise to any type of restriction to the desired scope of protection.

It is also clarified that the combustion system of the present invention does not lead to any alteration in a user's routine as far as handling of cooking utensils is concerned. This is because the user will merely continue on performing the desired burner so that the system will automatically conduct an intermittent procedure of opening and blocking injection of the fuel as indicated above.

Finally, attention should be drawn to the fact that the above description is only intended to describe, in an exemplary mode, some preferred embodiments of the combustion system for cooking equipment burners, in accordance with the present invention. Hence, as well acquainted by those skilled in the art, there can be a number of modifications, variations and constructional combinations of the elements which will exert the same function in the same way to achieve the same results, which are within the scope of protection, as limited by the appended claims.

Claims

1. Combustion system for cooking equipment burners, including a fuel feed duct (1) connected to a burner (2), said system being CHARACTERIZED in that it comprises: at least one combustion chamber (10) cooperating with an intermittent mechanism (3) for intermittently feeding fuel, air or an air / fuel mix into said combustion chamber (10); and at least one ignition element (4) cooperating with said intermittent mechanism (3).

2. Combustion system, in accordance with claim 1, CHARACTERIZED in that said intermittent mechanism (3 ') is electronic and comprises at least one valve acted by electric / electronic signals, such as an electromagnetic valve.

3. Combustion system, in accordance with claim 2, CHARACTERIZED in that said intermittent mechanism (3 ') is connected to at least one electronic controller (7) that controls fuel and / or air-fuel mix flow as well as the time interval of injecting fuel into said burner (2).

4. Combustion system, in accordance with claim 1, CHARACTERIZED in that said intermittent mechanism (3 ") is mechanical and comprises at least one valve (8) actuated by a lever (9) to release and block the fuel and / or air-fuel mix flow in the combustion chamber (10) of said burner (2).

5. Combustion system, in accordance with claim 4, CHARACTERIZED in that said valve (8) is interconnected to lever (9) through at least one return element (12).

6. Combustion system, in accordance with claim 1, CHARACTERIZED in that said combustion chamber (10) comprises at least one auxiliary air or air-fuel inlet at any ratio.

7. Combustion system, in accordance with claim 1, CHARACTERIZED in that said combustion chamber of burner (2) can be opened or closed.

8. Combustion system, in accordance with claim 1, CHARACTERIZED in that said ignition element (4) is electric / electronic or a small pilot flame fed by a parallel duct (1 1).