EP0860656A1

EP0860656A1 - Burner, in particular for hot air generators or the like

Info

Publication number: EP0860656A1
Application number: EP98102412A
Authority: EP
Inventors: Maurizio Giudice
Original assignee: Novimpianti Srl
Current assignee: Novimpianti Srl
Priority date: 1997-02-24
Filing date: 1998-02-12
Publication date: 1998-08-26
Also published as: IT1296212B1; ITPC970003A1

Abstract

The invention relates to a burner to be applied to hot air generators, in heating equipment using ventilated air, comprising a rounded main body (7), mounted on a support (5) that can be applied to the walls of a preferably cylindrical combustion chamber (1), said burner being provided with a connection (8) for gas feeding (9) and, on its end inside the combustion chamber, with a series of radial holes (10) disposed along a circle the axis of which corresponds with the axis of the combustion chamber and which provide jets directed to the outside.

At the inlet of the combustion chamber slanted wings (6) are provided, that give the inlet air flow a rotatory motion, so that the flame develops in contact with the inside walls of the combustion chamber (1), keeping them at a very high temperature and increasing the efficiency of the equipment.

Description

The present invention relates to a particular type of burner, which can be applied to hot air generators, in heating equipment using ventilated air or equivalent devices.

It is in particular a burner that allows the walls of the heat exchanger to reach a higher temperature as well as to be more compact, with the advantage of improving the thermic exchange between the combustion chamber and the zone in which the ventilated hot air is taken, that spreads out into the room to be heated.

It is known that the prior art in the field of heating is subdivided in different parts and it is based upon different techniques that can vary both upon the use of the equipment and, first of all, upon the feeding of the equipment itself.

Among the heat production devices which are most used nowadays, in particular in big rooms, there are the so called "heat pumps", i.e. devices apt to spread heat by way of ventilated air.

This equipment generally comprises one or more combustion chambers in which the burner is placed, and heat exchangers through which an airflow generated by a fan, passes.

The heated air comes out through outlet openings and spreads out into the room.

The burners of the known type, designed for this type of equipment, generally have a body comprising a series of nozzles through which the fuel - usually a gas - comes out.

The burner is placed in quite a big combustion chamber.

One of the main inconveniences of the above described equipment, is their low efficiency, since most of the hot smokes produced during the burning of the gas are exhausted, and for this reason most of the heating power of the equipment cannot be used to heat the ventilated air.

The cause of this is mainly the fact that the flame and the high temperature smokes that are produced by the burner can hardly lick for a long time the walls of the combustion chamber, because the flame develops far from the walls, and the most of the heat remains in the central part of the combustion chamber and is exhausted with the smokes.

In order to reach the required temperature of the external surface of the combustion chamber, (which is the zone licked by the ventilated air to be heated and which, for this reason, is provided with wings or the like that increase the exchange surface), it is often necessary to use high power burners and to burn an amount of fuel that is excessive if compared to the real efficiency of the heating system.

The aim of the present invention is to avoid or to reduce the inconveniences described above and in particular to propose a burner the main characteristic of which is to provide a high efficiency even when working in a very compact combustion chamber.

The main advantage of the invention consists in that the use of ventilated air equipment is provided, saving energy and obtaining a very high efficiency, since most of the heat produced is in contact with the exchanger walls and is kept as long as possible on said walls, before being exhausted.

The invention provides a burner that can be applied to a ventilated air heating equipment or the like, said burner comprising a rounded main body, mounted on a stirrup or a support that can be applied to the external surface of the walls of a combustion chamber, (preferably having a cylindrical shape), said burner being provided with a connection for gas feeding, while on the other side (the one inside the combustion chamber) it is provided with a series of radial holes disposed along a sector of a circle the axis of which corresponds with the axis of the combustion chamber.

Said holes are provided along the edge of the head and provide jets directed to the outside.

At the inlet of the combustion chamber some slanted wings are provided integral with the clamp, that give the inlet air flow a rotatory motion, so that the flame develops into contact with the inside walls of the combustion chamber, keeping them at a very high temperature and increasing the efficiency of the equipment.

The invention will be better understood reading the following description of a preferred embodiment shown as a not limiting example; in the annexed drawings:

Figure 1 is a schematic view from the underneath of a heating equipment according to the present invention, in its whole;
Figure 2 is a lateral schematic view of the same, showing the position of the burner with respect to the combustion chamber,
Figure 3 shows the schematic and perspective view of a possible embodiment of the combustion chamber; its contiguous parts improving the radiant surface in contact with the airflow;
Figure 4 is a schematic view of the combustion chamber and of the helicoidal heat flow;

With reference to the enclosed figures, n.1 indicates as a whole the combustion chamber - in which the burner 2 according to the present invention is placed - said chamber being placed in an equipment for the production of hot air which is directed to the rooms to be heated.

Combustion chamber 1 is preferably cylindrical and has a bottom wall 3, which is opposite to the inlet zone 4, this last being opened for the intake of the comburent airflow.

In correspondence of the inlet 4 a grid is mounted outside the burner by means of a diametral clamp 5, said grid being provided with a series of radial inclined wings 6, preferably integral with the clamp.

The body 7 of the burner 2 is fastened to the clamp 5, said body being cilindrical shaped or "pear-shaped" and being mounted on the clamp itself.

The outer part of the burner 2 is provided with a connection 8 for a gas-feeding pipe 9.

At the opposite side, i.e. near the edge of the head, the burner 7 is provided with a series of radial holes 10, which are designed so as to form a series of outside directed jets.

Two

bars

11 and 12 are also fastened to the clamp 5 and are directed towards the inner part of the burner; the first one provides an electrode 13 for the gas ignition, while a rod 14 is mounted on the end of the second one, said rod being provided with a temperature sensor.

It could be noted that the slanted wings 6 are disposed in such a way to compel the sucked comburent air to rotate, in order to lick the inner wall of the burner with a helicoidal flow; moreover the arrangement of the holes 10 is such that the flame develops not near to the body of the burner but right in contact with the wall of the chamber.

In this way the flame and the high temperature smokes develop in contact with the combustion chamber walls and lick the walls thanks to the helicoidal airflow given by the wings 6.

The outside wall of the combustion chamber can in this way reach high temperatures with a better thermal efficiency of the equipment.

Figure 4 highlights how both the direction of the flame produced by the burner and the path the hot air which is sucked through the slanted wings 6, keep the heat in contact with the inner wall of the combustion chamber; an outlet duct 15 is provided in the bottom wall 3.

Figure 3 shows, in its whole, a possible embodiment of a heating apparatus comprising the burner according to the invention, which can be used in an equipment for hot air production.

The combustion chamber is connected to an outlet pipe 15 directed to a radiant equipment comprising an intermediate chamber 16 and a series of pipes 17 that branch off from the said chamber and are directed into a second chamber 18.

From chamber 18 the exhaust smokes, which have already delivered their heat power, are expelled by means of equipment of a known type, not shown.

Both the combustion chamber and the radiant equipment in its whole are placed in a housing through which the ventilated air for room heating passes.

It is then clear the saving of energy allowed by the apparatus described above, as well as its high efficiency, since most of the heat produced is directed and kept on the exchange walls, and the heat remains as much as possible on said walls before being dispersed outside.

Said burner, which can be applied to ventilated air diffusion heating equipment or the like, has been described according to a preferred embodiment, but several different solutions could be provided; they will be technically the same as the shown one, and the will be considered within the scope of the present invention as defined by the appended claims.

Claims

Burner in particular for heat generators, characterised by the fact of providing means apt to direct the gas along a number of radial nozzles (10) directed towards the walls of the combustion chamber (1), and means (6) which give the comburent air a helicoidal motion along said chamber.
Burner in accordance with claim 1, characterised by the fact of providing a rounded body (7), in particular a cylindrical shaped body or a "pear-shaped" one placed within the combustion chamber (1) and provided with nozzles (10) apt to direct the gas radially towards the outside, and a number of slanted wings (6) at the inlet of the comburent air, so as to give the air a rotatory helicoidal motion along the walls of said combustion chamber.
Burner for heating generators in accordance with the preceding claims, characterised by the fact of providing a cylindrical shaped combustion chamber (1), means (6) apt to direct comburent air along the walls of said chamber and means (10) apt to direct the gas jet radially against the walls of said chamber.
Burner in accordance to the preceding claims, characterised by the fact of providing, at the inlet of the combustion chamber (1), a grid made of a series of slanted wings (6), an electrode (13) and a temperature sensor (14).
Burner in particular for hot air generators in accordance with the preceding claims, characterised by the fact of comprising a round-shaped body (7) mounted on a support (5) that can be fastened to the combustion chamber (1), said burner being provided at one side with a connection (8) for the gas feeding (9) and, on the other side - towards the inner part of the combustion - with a series of radial holes (10) disposed along a circle, a series of slanted wings (6) being provided at the inlet of the combustion chamber, to give the inlet air flow a rotatory motion.
Burner in accordance to the preceding claim, characterised by the fact that the axis of said circle corresponds with the axis of the combustion chamber.
Burner in accordance to the preceding claim, characterised by the fact that said nozzles (10) are provided near the edge of the head (7) and provide a series of jets directed towards the outside.
Heat generator comprising a burner in accordance with any of the preceding claims.