FR2659730A1 - Mixing device, especially for gas boilers - Google Patents

Abstract

The invention relates to a mixing device, especially for gas boilers. The subject of the invention is a mixing device, especially for gas boilers characterised in that it consists of a metal strip (1) fitted, on one side and/or the other, with lateral fins (2, 2') over its entire length, the strip being twisted in a helix about its axis (4), as is each fin (2, 2') about its own axis (3). Application in particular to gas boilers for heating or domestic hot water.

Description

TURBULATE: UR ESPECIALLY FOR A GAF BOILER
The present invention relates to a turbulator, in particular for a gas boiler producing hot water for heating only or for heating and domestic hot water.

 The principle of the turbulator is well known. I1 is a device arranged in the flow path of the burnt gases which are very hot, in order to evacuate part of their heat with their rejection. This device is intended to create turbulances in the gas flow to force them to better exchange calories with the walls of the ducts.

 Known systems generally consist of a metal ribbon pierced with cutouts alternately folded down on either side of the plane of the ribbon to form slowdown baffles. The ribbon is fixed in the flue gas duct.

 The object of the invention is to improve the heat exchanges between the gases and the wall of the duct.

 To this end, the subject of the invention is a turbulator, in particular for a gas boiler, characterized in that it consists of a metal strip provided with one side and / or the other with lateral fins, over its entire length, the ribbon being twisted in a helix along its axis, as well as each fin along its own axis.

 The device thus shaped fits into a cylinder and can be easily inserted into a flue gas evacuation duct and maintained by any suitable means. The helical shape of the turbulator forces the hot gases to "screw" into the exchange tubes and, by centrifugation, to better exchange with the internal wall of the tubes.

 Other characteristics and advantages will emerge from the description which follows of an embodiment of the device of the invention, description given by way of example only and with reference to the appended drawing in which the single figure represents a view in elevation. of a turbulator according to the invention.

 In this single figure, there is shown at 1 a thin metal strip or ribbon 1, for example made of stainless steel, provided on its two longitudinal sides with lateral indentations in the form of tongues or rectangular fins 2 with axis 3 perpendicular to the axis 4 of said ribbon 1.

 The two series of fins 2 are advantageously produced by cutting or stamping a thin flat strip, then the cut piece is twisted in a helix with an axis coincident with the axis 4 of the ribbon 1.

 By way of illustration, the single figure represents a band i twisted over a half-turn.

 In addition, each fin 2 is itself twisted in a helix as illustrated by the fin 2 'of the figure, the other fins not being, for the sake of simplification of the drawing, twisted.

 The pitch of the propeller formed by each fin 2, as well as the pitch of the propeller formed by the ribbon assembly 1 - fins 2, can vary within wide measures. They are also regular or not.

 The fins 2 have the same length L or not, same width 1 or not, and their spacing e, or not, can also vary.

 Finally, the ribbon i may have fins 2 on only one of its sides.

 Such a turbulator fits into a cylinder and can therefore be easily installed in a burnt gas conduit symbolized at 5 in the figure, with a vertical axis. It is sufficient to give the twisted assembly 1-2 a diameter slightly smaller than that of the conduit 5.

 The turbulator is for example held in the duct 5 by being simply retained at its upper end by two opposite tabs 6, of length greater than that of the fins, produced by cutting at the same time as them, and which come into abutment against the upper end of the conduit 5 as illustrated in the figure.

 Such a device makes it possible to progressively brake the burnt gases and much more effectively forces all of them to come and lick the internal wall of the conduit 5 so as to lose as quickly as possible a substantial part of their heat. It is indeed important, in order to have a good overall efficiency of the burner of a boiler, that the burnt gases exit at a temperature as low as possible in the anti-backdraft, while remaining at a temperature sufficient to avoid condensation of the water vapor contained in the combustion products evacuation pipe.

 The device of the invention can be adapted to any burner boiler evacuation ducts of any type, possibly adapting the retaining means (6) in place in the conduits.

 Finally, the invention is obviously not limited to the embodiment shown and described above, but on the contrary covers all variants thereof, in particular as regards the shape, dimensions and spatial distribution of the fins 2, and the pitch of the twists. produced on each fin and on the entire ribbon i along its axis 4.

Claims (3)

REVEDT CATIONS  1. Turbulator in particular for a gas boiler, characterized in that it consists of a metal strip (1) provided, on one side and / or the other, with lateral fins (2,2 ′), over its entire length, the ribbon being twisted in a helix along its axis (4), as well as each fin (2,2 ') along its own axis (3).  2. Turbulator according to claim 1, characterized in that the fins (2) have, before twisting, a rectangular shape and their length (L), width (1) and spacing (e) is variable or not.  3. Turbulator according to claim t or 2, characterized in that it is held in a duct (5) for evacuating combustion products while being suspended, at the upper end of the duct, using lateral tabs (6) or the like, obtained, like the fins (2,2 ′), by cutting. or stamping of the same thin plate, in particular of stainless steel and projecting outside the cylinder delimited by the twisted assembly (1-2).