EP3465060A1

EP3465060A1 - High efficiency heating device

Info

Publication number: EP3465060A1
Application number: EP17749513.2A
Authority: EP
Inventors: Orlando NIBOLI
Original assignee: Fondital SpA
Current assignee: Fondital SpA
Priority date: 2016-06-07
Filing date: 2017-06-07
Publication date: 2019-04-10
Also published as: EA037896B1; EA201892594A1; WO2017212415A1; CN109477702B; CN109477702A; ITUA20164170A1

Abstract

A high efficiency heating device (1) has a body (2) comprising an inner chamber (3) in which a heating liquid circulates; connections (16) communicating with the chamber (3) and extending from the body (2); and a front plate (4) having an outer face (9) facing in use the space to heat and defining a main front heat exchange surface (10) of the device (1); the chamber (3) is delimited by a pair of main walls (24, 25) facing each other and by a closed loop perimeter edge (7) connecting the main walls (24, 25); the chamber (3) has a ratio between surface and volume, expressed in dm2 and dm3, respectively, greater than or equal to 23.

Description

HIGH EFFICIENCY HEATING DEVICE

TECHNICAL FIELD

The present invention relates to a high efficiency heating device.

BACKGROUND ART

A common indoor heating system consists of radiators in which a heating liquid (typically hot water) circulates.

The radiators used in these systems may be made of various metal materials and are often formed of batteries of radiator elements which are manufactured separately and then joined together.

A typical radiator element has a substantially tubular body, provided with an inner chamber through which the water flows (water chamber) and with hydraulic connections for connection to other similar radiator elements and/or to a hydraulic circuit and arranged at the opposite ends of the element; two opposite partitions extend from the water chamber, along a centreline plane of the element, supporting, respectively, a front plate and a rear plate; a plurality of heat exchange fins extend from the tubular body.

It is generally believed that radiators comprising such elements are entirely satisfactory and have now reached the limits of their performance and can be improved no further, or at least only minimally, especially in terms of their specific power per unit of weight, i.e., the ratio between the thermal power emitted by the radiator element and transferred to the environment (measured according to specific standards, for instance EN 442), and the weight of the element (which is the fundamental parameter directly affecting production costs) .

The inventors of the invention in question have however ascertained that with the known solutions there is still significant room for improvement, particularly in terms of specific power and, generally, in terms of efficiency: the known radiators, even when characterised by good specific power, usually require a relatively high operating temperature (temperature of the water supplied to the radiator) .

On the other hand, it is widely acknowledged that a possible solution to the problem of increasing the power of a radiator is to increase the amount of water circulating in the radiator, i.e., to increase the volume of the water chamber. On the contrary, the inventors of the invention in question have discovered that the water used in the heat exchange is actually only the water that laps the walls of the water chamber, so that increasing the water content (i.e., the volume of the water chamber) does not necessarily lead to an increase in the thermal power.

DISCLOSURE OF INVENTION

One purpose of the present invention is therefore to provide a heating device, in particular made of aluminium, which can also be used instead of conventional radiators or radiator elements and which has high thermal efficiency.

The present invention thus relates to a heating device such as defined in its essential terms in the appended claim 1 and, in its secondary and preferred features, in the dependent claims.

The heating device according to the invention thus overcomes the technical problem of the limited power of the radiators known in the prior art. Compared to the conventional approach, in accordance with the invention the technical problem has been overcome by increasing the contact surface between the water (heating liquid) and metal (walls of the water chamber) but without limiting the space available for the convective motion of the air on the remaining part of the heating device and thus limiting the overall volume of the water chamber. The inventors of the invention in question have realised that to increase the power and general efficiency, the exchange of heat between the water and the metal must be improved, as the only water actually used in the heat exchange is the water that laps the walls of the water chamber.

According to the invention, it is therefore necessary to increase the exchange surface and instead reduce the amount of water, i.e., the volume of the water chamber, but without obstructing the convective motion of the water in the chamber.

Consequently, according to the invention the water chamber must be designed so that the ratio between surface and volume is greater than a minimum threshold.

Furthermore, this innovative approach enables the speed at which the water circulates to be increased and allows the flow regime to be changed from laminar to turbulent, thus further increasing the already greater thermal exchange surfaces.

The result is a particularly efficient heating device which, in particular, enables the heat from the heating liquid to be exploited to the full, and at the same time offers adequate resistance from a structural perspective.

Essentially, the device according to the invention is designed so that the water chamber has a large heat exchange surface but a relatively small volume: the volume occupied by the heating liquid (water) is thus reduced, but practically all of the water circulating in the chamber exchanges heat with the wall that delimits the chamber, thus increasing the overall heat exchange capacity. Moreover, the formation of areas in the chamber where the water remains at a high temperature and substantially releases no heat to the walls of the chamber is prevented, since the water is separated from the walls of the chamber by additional layers of water at a lower temperature.

In this way, the device according to the invention achieves a high level of efficiency, and can even operate with relatively low water temperatures.

Auxiliary heat exchange surfaces extend directly from the walls of the water chamber, and these too exploit all of the heat from the heating liquid.

The optional addition of auxiliary parts and components inside the chamber (such as turbulators or other elements to deflect or convey the water flow; ties to increase the mechanical strength, etc.) further improves efficiency, in that the presence of such additional elements also contributes to reduce the volume available for the water and increase the heat exchange surfaces available to the water . BRIEF DESCRIPTION OF THE DRAWINGS

Further characteristics and advantages of the present invention will become clear from the description of the following non-limiting embodiments thereof, with reference to the figures of the accompanying drawings, in which:

- Figure 1 is a perspective view of a first embodiment of a heating device according to the invention;

- Figure 2 is a side view of the device shown in Figure i;

- Figures 3 and 4 are two section views along the dashed lines III-III and IV-IV, respectively, of Figure 2;

- Figure 5 is a perspective view of a second embodiment of the heating device according to the invention;

- Figures 6 and 7 are, respectively, a longitudinal section view and a cross section view of the heating device of Figure 5.

BEST MODE FOR CARRYING OUT THE INVENTION

In Figures 1 and 2, denoted as a whole by reference numeral 1 is a heating device (for heating environments inside buildings) of the liquid circulation (for example, hot water) type.

The device 1 comprises a body 2 made of a heat conducting material, for example (but not necessarily) a metal material, in particular aluminium (said term also comprising aluminium alloys, i.e., alloys containing aluminium) and for example aluminium obtained by die-casting (i.e., made of aluminium or an alloy containing aluminium produced by means of a die-casting process) . It is understood that the body 2 may be made of another material, provided it is suitable for conducting heat (such as ceramic, polymeric, composite and other materials), and produced by means of other production processes (for example, by means of an extrusion process) .

Also with reference to Figures 3 and 4, the body 2 is a hollow body and is provided with an inner chamber 3 (water chamber) in which a heating liquid (for example, hot water) circulates when in use.

The body 2 comprises a front heat exchange plate 4 and a rear heat exchange plate 5, positioned at respective opposite ends of the body 2 (precisely, with reference to the normal position of use of the device 1, a front end and a rear end) and substantially facing one another and joined along respective peripheral edges 6 which together form a closed loop perimeter edge 7 of the chamber 3.

In the example shown in Figures 1-4, the plates 4, 5 have a substantially quadrangular shape (being for example substantially square or rectangular) , but it is understood that the plates 4, 5 may be of a different shape.

The front plate 4 has an inner face 8 facing the chamber 3 and wet by the heating liquid and which thus exchanges heat with the heating liquid in the chamber 3 (receiving heat from the heating liquid) ; and an outer face 9, opposite to the inner face 8 and defining a first heat exchange surface 10, in particular a main front heat exchange surface of the device 1, facing, when in use, the environment to be heated and which exchanges heat with the air in the environment in which the device 1 is installed (releasing heat into the air) , in addition to releasing heat into the environment by radiation.

Likewise, the rear plate 5 has an inner face 11 facing the chamber 3 and wet by the heating liquid and which thus exchanges heat with the heating liquid in the chamber 3 (receiving heat from the heating liquid) ; and an outer face 12, opposite to the inner face 11 and defining a second heat exchange surface 13, facing, when in use, a supporting wall W to which the device 1 is fixed by fastening members (of a type known and not illustrated here for the sake of simplicity) and which exchanges heat with the air in the environment in which the device 1 is installed (releasing heat into the air) .

The surface 10 defines a main front heat exchange surface of the device 1, facing the environment to be heated and opposite to the supporting wall W to which the device 1 is fixed.

The chamber 3 extends along a longitudinal axis A, vertical when in use, and a transverse axis B, horizontal when in use, defining, respectively, the height and width of the chamber 3; and along a third axis C, perpendicular to the longitudinal axis A and to the transverse axis B and defining the thickness of the chamber 3.

The chamber 3 is delimited at the front by the front plate 4 and precisely by the inner face 8 of the front plate

4 facing the chamber 3; and at the back by the rear plate 5 and precisely by the inner face 11 of the rear plate 5, facing the inner face 8 of the front plate 4.

The inner face 8 of the front plate 4 and the inner face 11 of the rear plate 5 face one another and are spaced apart so that the distance between them defines the thickness of the chamber 3.

The thickness of the chamber 3 is thus defined as the distance between the front plate 4 and the rear plate 5 and precisely between the inner face 8 of the front plate 4 and the inner face 11 of the rear plate 5.

The plates 4, 5 need not necessarily be plane and parallel as illustrated in Figures 1-4, but may have different shapes and be arranged differently: for example, one or both of the plates 4, 5 could be curved, corrugated, etc.; and/or the plates 4, 5 could slope towards one another.

The chamber 3 may also have a variable (different) thickness

(measured parallel to the axis C) along the longitudinal axis A and/or along the transverse axis B.

Preferably, as illustrated, the chamber 3 is a thin chamber, with a thickness that is smaller (in at least one or more parts of the chamber 3 if not throughout the chamber 3) with respect to the other dimensions (height and width) and with respect to at least one from between the height and the width.

In particular, in the embodiment that is illustrated (though not necessarily) the chamber 3 has a generally flattened shape and mainly extends along the longitudinal axis A, vertical when in use, and the transverse axis B, horizontal when in use, defining, respectively, the height and the width of the chamber 3; and the chamber 3 has a thickness, measured perpendicularly to the longitudinal axis A (vertical when in use) and to the transverse axis B (horizontal when in use), i.e., along the axis C (perpendicular to the longitudinal axis A and to the transverse axis B) which is smaller than the height and the width .

For example, the chamber 3 has a maximum thickness (thus considering the maximum thickness of the chamber 3, if the chamber 3 has a different thickness in different areas of the chamber 3) that is at least 20 times smaller, preferably 30 times smaller, more preferably at least 40 times smaller than each transverse dimension (measured in a direction perpendicular to the thickness), i.e. than the height and than the width, of the front plate 4. Thus, with reference to the normal position of use of the device 1 (meaning the position in which the front plate 4 is substantially vertical and facing the environment to be heated) , the chamber 3 has a height and a width each of which is at least 20 times greater, preferably at least 30 times greater and even more preferably at least 40 times greater than the thickness of the chamber 3.

In the example illustrated in Figures 1-4, the chamber 3 substantially extends on the entire front plate 4 with the exception of the peripheral edge 6 of the front plate 4 joined to the corresponding peripheral edge 6 of the rear plate 5.

In particular, the chamber 3 extends on at least 60% of the front plate 4: at least 60% of the surface of the inner face 8, facing the chamber 3, of the front plate 4 thus faces the chamber 3.

In other words, the chamber 3 occupies at least 60% of the inner face 8 of the front plate 4, i.e., the chamber 3 has a contact surface with the inner face 8 of the front plate 4 (meaning the surface of the chamber 3 delimited on the inner face 8 of the front plate 4 from the perimeter edge 7 and thus excluding any spaces inside the chamber 3 occupied by internal elements such as spacers, ribs, structural reinforcements, flow conveyors, etc., which will be described later on) that is at least 60% of the overall surface of the inner face 8 of the front plate 4.

In other embodiments, the chamber 3 extends on at least 65%, or at least 70%, or at least 75%, or at least 80%, or at least 85%, or at least 90% of the surface of the inner face 8 of the front plate 4.

The body 2 is further provided with connections 16 extending from one or both of the plates 4, 5 and communicating with the chamber 3.

In the example in Figures 1-4, in particular, the connections 16 project from the rear plate 5 and precisely from the outer face 12 of the rear plate 5 and are substantially perpendicular to the rear plate 5 and to the outer face 12 of the rear plate 5.

In the example that is illustrated, the device 1 has four connections 16 positioned at respective corners of the chamber 3. It is nonetheless understood that the body 2 may be provided with a different number of connections 16, also arranged in other positions, not necessarily at the corners of the chamber 3. Preferably, but not necessarily, the connections 16 are positioned along the perimeter edge 7 of the chamber 3.

The connections 16 are defined by respective sleeves, for example but not necessarily substantially cylindrical (but the sleeves may also have a different shape) , and their purpose is to connect the device 1 to an external hydraulic circuit (not illustrated) and/or to connect the device 1 to other identical devices to define a modular system (as described later on in this document) .

The connections 16 that are not used to connect the device 1 to another identical device to define a modular system or to connect the device 1 to the external hydraulic circuit are closed by plugs (not illustrated) .

In general, the chamber 3 has at least one inlet 16a and one outlet 16b defined by respective connections 16.

In the example that is illustrated, the front plate 4 and the rear plate 5 are both substantially plane and parallel; it is understood that the front plate 4 and/or the rear plate 5, like their faces, may have a different shape, for example curved, corrugated, etc.

The outer face 9 of the front plate 4 is, for example, substantially smooth.

In the embodiment illustrated in Figures 1-4, the rear plate 5 supports a plurality of heat exchange fins 17 which extend outside the chamber 3 from the rear plate 5 and precisely from the outer face 12 of the rear plate 5.

In the non-limiting example that is illustrated, the fins 17 are substantially perpendicular to the outer face 12 of the rear plate 5 and parallel to one another and to the longitudinal axis A (vertical when in use) . It is understood that the fins 17 may be formed and arranged differently, i.e., the fins 17 may have a different shape, they may be oriented in a different way, arranged differently with respect to one another compared with that illustrated merely by way of example.

Preferably, as illustrated in Figures 1-4, all of the fins 17 extend directly from the chamber 3, since they are joined directly to a wet wall 18 of the chamber 3, in this case defined by the rear plate 5, so that all of the fins 17 are so-called "wet fins". All of the fins 17 have a root edge 19 joined to the wet wall 18 of the chamber 3, which comes directly into contact with the heating liquid.

The front plate 4 and the rear plate 5 comprise or constitute respective main walls 24, 25 of the chamber 3 with respective inner surfaces 26, 27 facing the chamber 3 and wet by the heating liquid contained in the chamber 3.

The term "main walls" refers to the walls of the chamber 3 (i.e., the walls that delimit the chamber 3 and come directly into contact with the heating liquid contained in the chamber 3) with a larger surface extension (area) than every other wall of the chamber 3.

The front plate 4 and the rear plate 5 thus comprise or constitute the main walls 24, 25 of the chamber 3 and precisely a front wall 24 that, in use, faces the environment to be heated, and a rear wall 25 that, in use, faces the wall W of the environment to be heated. The inner faces 8, 11 of the plates 4, 5 define (or comprise) the inner surfaces 26, 27 of the main walls 24, 25.

The chamber 3 is delimited by the two main walls 24, 25, facing one another and defined in the embodiment illustrated in Figures 1-4 by the plates 4, 5; and by the perimeter edge 7 connecting the main walls 24, 25 to one another and has an extension (surface) that is smaller than each of the main walls 24, 25.

The chamber 3 has a generally flattened shape.

In particular, the chamber 3 has a ratio between surface and volume, expressed in dm2 and dm3, respectively, greater than or equal to 23; preferably, said ratio is greater than or equal to 33, or greater than or equal to 36, or greater than or equal to 40, or greater than or equal to 50.

Moreover, the chamber 3 has a surface of at least 2 dm2.

The chamber 3 has, in a cross section perpendicular to the longitudinal axis A, a ratio between width and depth greater than or equal to 20 and preferably greater than or equal to 30, more preferably greater than or equal to 40.

The width in a cross section of the chamber 3 is defined as the maximum distance, measured in the cross section parallel to the transverse axis B, between opposite portions of the edge 7; and the depth in a cross section of the chamber 3 is defined as the maximum distance, measured in the cross section parallel to the axis C, between the main walls 24, 25 and precisely between respective inner faces of the main walls 24, 25.

In the embodiment shown in Figures 1-4, the main walls

24, 25 are substantially parallel to the main front heat exchange surface 10 of the device 1.

The front plate 4 and the rear plate 5, comprising the main walls 24, 25 of the chamber 3 and the respective peripheral edges 6 shaped so as to couple with one another, are advantageously formed of respective monolithic pieces, made for example of aluminium obtained by means of a die- casting process; the two pieces that make up the two plates 4, 5 are then joined along the respective peripheral edges 6, so as to form a mechanical and fluid-tight joint.

Advantageously, the plates 4, 5 are joined by means of a thermo-electric melting process, performed by circulating current through respective contact portions of the pieces to be joined to cause the local melting thereof, without the contribution of welding material (as described in international patent application W02014 / 155295 ) .

The plates 4, 5 may, however, be joined in other ways, for example by means of mechanical joining methods (possibly with the interposition of sealing gaskets), gluing, other types of welding (not necessarily electromagnetic), etc. Advantageously, the fins 17 are made as an integral part of the plate 5 from which they project so as to form a monolithic piece therewith (i.e., the fins are not borne by or joined to the plate 5, but are made directly with the plate 5, for example during an extrusion or die-casting step) .

Inside the chamber 3 there are ties 33, i.e., projections that extend between the front plate 4 and the rear plate 5 (i.e., between the main walls 24, 25) and are integral with (firmly joined to or made as a single piece with) the inner face 8 of the front plate 4 and with the inner face 11 of the rear plate 5, i.e., with respective inner faces, facing the chamber 3, of the main walls 24, 25.

In the example that is illustrated, the ties 33 are made as a single piece with one of the plates 4, 5 and extend towards the opposite plate, to which they are joined, for example, by means of welding or thermo-melting when the plates 4, 5 are joined to one another to form the device 1, in particular by means of a local thermo-electric melting process on each tie 33 (but it is understood that the plates 4, 5, as already mentioned, may be joined to one another in other ways) ; in particular, the ties 33 are shaped as protuberances on the inner face 11 of the rear plate 5 (and are made for example by being die-cast with the plate 5) and are welded to the inner face 8 of the front plate 4. Alternatively, the ties 33 may be made separately and welded to the two plates 4, 5; or even made as integral parts of both of the plates 4, 5.

Essentially, depending on the technology used in the production of the body 2, the ties 33 may be defined directly as integral parts of both of the plates 4, 5; or as integral parts of one of the plates 4, 5 which are then joined (welded) to the other plate; or as separate components which are then joined (welded) to both of the plates 4, 5.

The ties 33 are distributed on the faces 8, 11 and their main function is to increase the mechanical strength of the device 1, in particular to improve its resistance to pressure. The ties 33 also contribute to making the device 1 fluid tight, in that they contribute to keeping the two plates 4, 5 joined together so as to prevent any leakage of liquid .

Since the ties 33 are inserted along the path of the heating liquid in the chamber 3, they also have a function of distributing the heating liquid in the chamber 3.

In general, advantageously but not necessarily, the chamber 3 houses between the two plates 4, 5 internal elements 34 (which may also include the ties 33) which act on the flow of the heating liquid circulating in the chamber 3, for example to define one or more paths in the chamber 3, to distribute the heating liquid in the chamber 3, to modify the motion of the heating liquid in the chamber 3, etc.

In particular, the elements 34 (or at least some of the elements 34) are shaped and arranged so as to aid the even distribution of the water in the chamber 3.

In the preferred embodiment illustrated in Figure 4, the elements 34 comprise, in addition to the ties 33, a first distributor 35a, positioned at a top end 36a of the chamber 3, and/or a second distributor 35b, positioned at a bottom end 36b of the chamber 3 (again with reference to the normal position of use of the device 1: the ends 36a, 36b are axially opposite ends with respect to the longitudinal axis A) .

The distributors 35a, 35b are defined by respective transverse walls, for example substantially parallel to the transverse axis B (or slanting with respect to the transverse axis B, or curved or even differently shaped) which extend between the inner face 8 of the front plate 4 and the inner face 11 of the rear plate 5 and between two lateral opposite sides of the chamber 3 and are provided with respective series of longitudinally spaced through apertures 37. The distributor 35a is positioned close to and below an inlet 16a, defined by one of the sleeves 16 and positioned at the top end 36a of the chamber 3. The distributor 35a is positioned close to and below an inlet 16a, defined by a first connection 16 positioned at the top end 36a of the chamber 3; and the distributor 35b is positioned close to and above at least one outlet 16b, defined by another connection 16 positioned at the bottom end 36b of the chamber 3.

In the preferred embodiment illustrated in Figure 4, the chamber 3 has an inlet 16a, defined by a first connection 16 positioned at a top end of the chamber 3; and two outlets 16b, defined by respective further connections 16 positioned at the bottom end of the chamber 3 and at respective opposite lateral ends of the chamber 3. In use, the heating liquid enters the chamber 3 through the inlet 16a and flows out through both of the outlets 16b, after being distributed substantially evenly inside the chamber thanks to the distributors 35a, 35b.

The chamber 3 may also house just one of the distributors 35a, 35b. The shape of the distributors 35a, 35b may also differ from that illustrated and described here purely by way of example.

The presence of the ties 33, and generally of the elements 34, and of any other auxiliary components inside the chamber 3, contributes to reduce the volume available for the water and to increase the heat exchange surfaces available for the water, further improving the efficiency of the device 1.

Figures 5-7, in which details similar or identical to those already described are denoted by the same reference numerals, show a second embodiment of the heating device 1 according to the invention.

Also in this embodiment the device 1 comprises a body 2 made of a heat conducting material (for example aluminium) provided with an inner chamber 3 (water chamber) through which, in use, the heating liquid (hot water) circulates.

In this case the body 2 is configured so as to be used in place of a conventional radiator element to form a battery of radiator elements arranged side by side.

The chamber 3 has a generally flattened shape and mainly extends along a longitudinal axis A, vertical when in use, and a transverse axis B, horizontal when in use, defining, respectively, the height and the width of the chamber 3.

The chamber 3 has a height and a width measured, respectively, along a longitudinal axis A (vertical when in use) and a transverse axis B (horizontal when in use) , and a thickness measured along an axis C (also horizontal when in use) perpendicular to the longitudinal axis A and to the transverse axis B.

The chamber is again delimited by a pair of opposite main walls 24, 25, facing one another, and by a perimeter edge 7, which connects the main walls 24, 25 to one another and has a surface that is smaller than each of the main walls 24, 25.

Also according to this embodiment, the chamber 3 has a generally flattened shape, as described above.

Moreover, the chamber 3 has a surface of at least 2 dm2.

The chamber 3 has, in a cross section perpendicular to the longitudinal axis A, a ratio between width and depth (again measured as the maximum distances in the cross section between opposite portions of the edge 7 and, respectively, between the main walls 24, 25) greater than or equal to 20 and preferably greater than or equal to 30, more preferably greater than or equal to 40.

Also according to this embodiment, the chamber 3 mainly extends in height and width, respectively, along the longitudinal axis A and the transverse axis B; and has a thickness, measured along the axis C perpendicular to the longitudinal axis A and to the transverse axis B, that is significantly less than the height and the width.

The thickness of the chamber 3 is again defined as the distance between the main walls 24, 25 (thus measured along the axis C) and precisely between respective inner surfaces 26, 27 of the main walls 24, 25.

But now the main walls 24, 25 are substantially perpendicular to the main front heat exchange surface 10 of the device 1 (and not, as in the embodiment described with reference to Figures 1-4, substantially parallel to the surface 10) .

In other words, with reference to the normal position of use of the device 1, the main walls 24, 25 define respective lateral sides of the device 1.

The surface 10 consists of an outer face 9 of a front plate 4 which protrudes from the perimeter edge 7 of the chamber 3.

In particular, the plate 4 is joined to a front portion

28a of the perimeter edge 7 of the chamber 3.

In the example shown in Figure 7, the plate 4 is joined to the edge 7 by a longitudinal seam 29 (parallel to the longitudinal axis A) and extends on opposite sides of the seam 29.

Optionally, the body 2 also comprises a rear plate 5, which extends from a rear portion 28b of the perimeter edge 7 of the chamber 3.

The plate 5, like the plate 4, is also for example joined to the edge 7 by a longitudinal seam 29 (parallel to the longitudinal axis A) .

Preferably, the plate 4 and/or the plate 5 are completely or at least partly in direct contact with the heating liquid contained in the chamber 3, i.e., they have at least respective wall portions that delimit the chamber 3, forming respective portions of the edge 7 of the chamber 3. In this way, the plate 4 and/or the plate 5 are also so- called "wet fins".

In addition to the plates 4, 5, the device 1 comprises further heat exchange surfaces defined by a plurality of heat exchange fins 17 which extend outside the chamber 3 from the main walls 24, 25.

In the non-limiting example that is illustrated, the fins 17 are substantially perpendicular to the main walls 24, 25 and parallel to one another and to the longitudinal axis A (vertical when in use) . It is understood that the fins 17 may be formed and arranged differently.

Preferably, also in this case all of the fins 17 extend directly from the chamber 3, since they are joined directly to wet walls 18 of the chamber 3, in this case defined by said main walls 24, 25 of the chamber 3, so that all of the fins 17 are "wet fins".

The connections 16 are arranged in pairs at respective opposite longitudinal ends (positioned along the longitudinal axis A) , respectively, in use, a top end and a bottom end of the body 2.

The connections 16 extend from both of the walls 24, 25 and are substantially perpendicular to the walls 24, 25; the connections 16 positioned at a same longitudinal end are aligned with one another parallel to the axis C.

Also in the embodiment illustrated in Figures 5-7, the body 2 is advantageously (but not necessarily) formed by two monolithic pieces, each comprising one of the main walls 24, 25 and a respective peripheral edge 6.

The peripheral edges 6 are shaped so as to couple with one another to form the perimeter edge 7 of the chamber 3.

The pieces that comprise the main walls 24, 25 and the respective peripheral edges 6 are made for example of aluminium obtained by die-casting and joined, advantageously by means of the thermo-electric melting process described previously, along the respective peripheral edges 6, so as to form a mechanical and fluid- tight joint .

Although not illustrated for the sake of simplicity, also in the embodiments illustrated in Figures 5-7 the chamber 3 may house ties 33, arranged between the main walls 24, 25 and firmly joined to both of the inner surfaces 26, 27 of the main walls 24, 25; and/ or other internal elements which act on the flow of the heating liquid circulating in the chamber 3 and are shaped and/or arranged so as to aid an even distribution of the heating liquid in the chamber 3.

Lastly, it is understood that further modifications and variations can be made to the heating device described and illustrated herein without departing from the scope of the invention as set forth in the appended claims .

Claims

1. A high efficiency heating device (1) , having a body

(2) comprising an inner chamber (3) extending along a longitudinal axis (A) , substantially vertical in use, and in which a heating liquid circulates; connections (16) communicating with the chamber (3) and extending from the body (2) ; and a front plate (4) having an outer face (9) facing in use the space to heat and defining a main front heat exchange surface (10) of the device (1) ; the chamber (3) being delimited by a pair of main walls (24, 25) facing each other and by a perimeter edge (7) connecting the main walls (24, 25) ; the device (1) being characterized in that the chamber (3) has a ratio between surface and volume, expressed in dm2 and dm3, respectively, greater than or equal to 23.

2. A device according to claim 1, wherein the chamber

(3) has a ratio between surface and volume, expressed in dm2 and dm3, respectively, greater than or equal to 33 or greater than or equal to 36 and preferably greater than or equal to 40 and more preferably greater than or equal to 50.

3. A device according to claim 1 or 2, wherein the chamber (3) has a surface of at least 2 dm2.

4. A device according to one of the preceding claims, wherein the chamber (3) has, in a cross section perpendicular to the longitudinal axis (A) , a ratio between width and depth greater than or equal to 20 and preferably greater than or equal to 30, more preferably greater than or equal to 40.

5. A device according to one of claims 1 to 4, wherein the main walls (24, 25) of the chamber (3) are substantially parallel to the main front heat exchange surface (10) of the device (1) .

6. A device according to claim 5, wherein one of said main walls (24, 25) of the chamber (3) is a front wall (24) , facing in use the space to heat, of the chamber (3) ; and the front plate (4) comprises or consists of said front wall (24) of the chamber (3) .

7. A device according to one of claims 1 to 4, wherein the main walls (24, 25) are perpendicular to the main front heat exchange surface (10) of the device (1) .

8. A device according to claim 7, wherein the main walls (24,

25) define respective lateral sides of the chamber (3) , perpendicular to the front plate (4) .

9. A device according to one of the preceding claims, wherein the body (2) supports heat exchange fins (17) which project from the body (2) outside the chamber (3) .

10. A device according to one of the preceding claims, wherein the body (2) is formed by two monolithic pieces joined along respective peripheral edges (6), each piece comprising one of the main walls (24, 25) of the chamber (3) .

11. A device according to one of the preceding claims, wherein inside the chamber (3) there are ties (33) which extend between the opposite main walls (24, 25) of the chamber (3) and are integral with respective inner surfaces (26, 27) of both of said main walls (24, 25) .

12. A device according to claim 11, wherein the ties (33) are integrally joined to the main walls (24, 25) of the chamber (3) , being made in one piece or welded and/or melted with said main walls (24, 25) .

13. A device according to one of the preceding claims, wherein the chamber (3) houses between the two plates (4, 5) internal elements (34) which act on the flow of the heating liquid circulating in the chamber (3) and are shaped and/or arranged so as to aid an even distribution of the heating liquid in the chamber (3) .

14. A device according to claim 13, wherein the elements (34) comprise a first distributor (35a) , positioned at a top end (36a) of the chamber (3), and/or a second distributor (35b), positioned at a bottom end (36b) of the chamber (3) .