WO2013076567A2

WO2013076567A2 - Perfected heat exchanger and production method

Info

Publication number: WO2013076567A2
Application number: PCT/IB2012/002456
Authority: WO
Inventors: Bruno PILOSIO
Original assignee: Pilosio Bruno
Priority date: 2011-11-25
Filing date: 2012-11-22
Publication date: 2013-05-30
Also published as: WO2013076567A3; ITUD20110191A1

Abstract

A heat exchanger comprises a plurality of pipes (12) disposed substantially parallel to each other, fluidically connected and in which a beat-carrying fluid is made to pass, a plurality of heat exchange fins (11), and at least a head (14) through which end segments (12a, 12b) of said pipes (12) pass. Channels are made in said head (14), to connect said pipes and to define the passage of the heat-carrying fluid.

Description

"PERFECTED HEAT EXCHANGER AND PRODUCTION METHOD"

FIELD OF THE INVENTION

The present invention concerns heat exchangers, for example of the finned type, also known as exchanger batteries, which are used for different applications with both a cooling and heating function. A particular application of the present invention is for air conditioning systems in which the cooling gases used can reach working pressures of up to about 60 atmospheres.

BACKGROUND OF THE INVENTION

Finned type heat exchangers consist of a coil in which a hot or cold heat- carrying fluid flows.

The coil consists of a plurality of U-shaped pipes, the ends of which are connected to each other by means of a curved pipe, also U-shaped and called bent pipe.

A certain number of fins are solidly associated with the coil, transversely to the longitudinal extension of the pipes, with the function of increasing the heat exchange surface.

The fins, with a thickness comprised between 0.1 mm and 0.2 mm, are normally distanced from each other by collars made in a single body with the fins. The collars are obtained by molding and consist of hollow cylinders which rise up from the surface of the fins, and through which the pipes of the coil are made to pass.

The pipes are made solid with the fins by a chucking operation, thus increasing both the efficiency of the heat exchange and also the structural rigidity. After chucking, the pipes are connected to each other by the bent pipes to create the coil immersed in the pack of fins.

Every mechanical operation to make the exchangers (molding the fins, chucking and bending) must be lubricated.

Subsequently, once the fins have been associated with the pipes, the bent pipes are normally associated with each end of the U-shaped pipes, and connect two successive pipes with each other.

The bent pipes are inserted and positioned by hand at the free ends of the pipes before the welding process in which the hydraulic seal is achieved between the pipe and the bent pipe. The operation to position and subsequently weld the bent pipes requires a very long time, and this also entails a high cost of the product obtained.

Furthermore, the welding operation must be carried out by specialized personnel and it does not always guarantee the correct hydraulic seal of the coil. There are therefore frequent cases in which, for example following the testing of the heat exchanger, it is necessary to intervene again on the join zone in order to guarantee the correct hydraulic seal.

Another disadvantage of the known production process is that normally, and especially when molding the fins, lubricating oils are used that then have to be removed.

To reduce this disadvantage, over time the various whole lubricating oils, mineral or synthetic, have been replaced by products containing from 50 to 90% of evaporating solvent (so-called evaporating lubricants), in order to reduce the residue and hence to obtain sufficiently clean fins that do not have to be de- greased.

Technical solutions are known, for example from documents EP-A-0.421.955 and EP-A-0.228.330, which provide to eliminate the bent pipes and hence the welding operations, using a head into which the pipes are inserted. The head defines connection channels between two or more end segments of the pipes, so as to define a closed circuit in which the heat-carrying fluid circulates. The head described in these documents consists of a plurality of components that are reciprocally associated with each other. The end segments of the pipes are made solid with the head by gluing. These solutions of the above documents have the disadvantage that they require a large number of components to obtain the above- mentioned head. Furthermore, there are also problems connected to the fluid- dynamic seal of the head and leakages of the heat-carrying fluid in transit at high pressures in the heat exchanger.

The present invention proposes a series of purposes relating to the current state of the art.

A first purpose is to eliminate the bent pipes and thus eliminate the time required for inserting them, and all that is connected with them. Consequently there is therefore another purpose to eliminate the weldings and, connected therewith, to eliminate the consumption of gas, free flames and connected fumes.

Another purpose of the present invention is to replace current pipes made of copper that make up the coil with less expensive pipes made of aluminum. Another purpose is to simplify the machines and equipment that are used to make finned batteries.

Another purpose of the present invention is to obtain a heat exchanger which is able to function even at high working pressures, preventing losses due to leakage of the cooling gas in transit.

It is therefore also a purpose of the present invention to obtain a heat exchanger which is economical and that can be made using a simple and quick method.

The Applicant has devised, tested and embodied the present invention to overcome the shortcomings of the state of the art and to obtain these and other purposes and advantages.

SUMMARY OF THE INVENTION

The present invention is set forth and characterized in the independent claims, while the dependent claims describe other characteristics of the invention or variants to the main inventive idea.

In accordance with the above purposes, a heat exchanger according to the invention comprises a plurality of pipes, disposed substantially parallel to each other, advantageously but not necessarily made of aluminum, into which a plurality of heat exchange fins are inserted, leaving suitable end segments of the pipes free and located outside the pack of fins.

The free segments of pipe are inserted into a head of the heat exchanger, advantageously made of plastic and/or metal material and in which a plurality of connection channels are made.

Each of the connection channels is configured to connect fluidically at least two end segments of the pipes to define, all in all, a fluid-dynamic circuit for the passage at high pressures of the heat-carrying fluid, that is, pressures from 20-30 kg/cm² and more, up to about 60 kg/cm².

According to one form of embodiment, the head comprises at least a connection element provided with a plurality of through holes through which the end segments of the pipes are inserted, and at least a covering panel associated with the connection element and in which the connection channels are made. According to a first solution, the through holes have a truncated cone shape for at least most of their height.

According to a variant, for a considerable part of their height, the through holes have a cylindrical glass type shape, that is, a shape at least partly cylindrical with two different diameters.

Between the connection element and the covering panel, a hydraulic seal element is interposed, which comprises a base from which a plurality of protruding elements extend, provided with a respective through hole and configured to be inserted into the holes of the connection element for the insertion of one of the end segments of a pipe. According to a preferential solution, at least part of the hydraulic seal element is made of a material that is deformable under pressure.

The connection element, the covering panel and the hydraulic seal element are reciprocally connected to obtain the head.

The particular configuration of the connection element and the hydraulic seal element allows to increase the fluid-dynamic seal effect compared with the state of the art.

In this case, in fact, the hydraulic seal element is subject during use to the action of the pressure of the heat-carrying fluid that thrusts it against the connection element.

The pressure action of the fluid is also translated into a compression action that allows to obtain a better seal on the perimeter surface of the end segments of the pipes; the compression also provides to constrain the pipes through interference to the head, preventing them from becoming detached therefrom.

According to a variant, the heat exchanger can be provided with two heads as described above, each of which is associated with the respective ends of the pipes.

According to another variant, at least one of either the connection element or the covering panel are obtained by injection in a mold.

It comes within the spirit of the invention to provide that at least one of the entrance and exit connections of the heat-carrying fluid in circulation is provided in the connection element and/or covering panel. It is obvious that the plastic material that makes up the connection element and/or the covering panel is chosen at least according to the temperatures of the fluid, liquid or gaseous, transiting in the coil.

According to a variant, at least the end segments of the pipes have a chemical or mechanical surface treatment, able to improve the anchorage and/or pipe- plastic seal in the connection element.

DESCRIPTION OF THE DRAWINGS

These and other characteristics of the present invention will become apparent from the following description of a preferential form of embodiment, given as a non-restrictive example with reference to the attached drawings wherein:

- fig. 1 is a front view of the perfected heat exchanger with a single connection head according to the present invention;

- fig. 2 is a plan view of a part of the connection head in fig. 1 ;

- fig. 3 is a three-dimensional view of a part of the connection head in fig. 1 ; - fig. 4 is a section view from A to A in fig. 2 of a first variant for clamping pipes in a component of the connection head;

- fig. 5 is a section view of a second variant for clamping pipes in the connection head;

- fig. 6 is a section view of a first variant of fig. 4;

- fig. 7 is a section view of a second variant of fig. 4;

- fig. 8 is a section view of a third variant of fig. 4;

- fig. 9 is a section view of a fourth variant of fig. 4;

- fig. 10 is a section view of a fifth variant of fig. 4;

- fig. 11 is a section view of a variant of fig. 10;

- fig. 12 is a plan view of a first component of fig. 1 1 ;

- fig. 13 is a section view from B to B in fig. 12;

- fig. 14 is a perspective view of a second component of fig. 12;

- figs. 15 and 16 are section views of variants of fig. 11;

- fig. 17 is a plan view from below of the component in fig. 14;

- fig. 18 is a view of a variant of fig. 17;

- figs. 19 and 20 are schematic representations of an apparatus used to make the component in fig. 14;

- fig. 21 is a view of a variant in fig. 11. To facilitate comprehension, the same reference numbers have been used, where possible, to identify identical common elements in the drawings. It is understood that elements and characteristics of one form of embodiment can conveniently be incorporated into other forms of embodiment without further clarifications.

DESCRIPTION OF SOME FORMS OF EMBODIMENT

With reference to fig. 1, a heat exchanger according to the present invention is indicated in its entirety by the reference number 10.

The heat exchanger 10 comprises a head 14 made of plastic material, to which a plurality of U-shaped pipes 12 are connected. In the segments of pipe 12 longitudinal and parallel to each other a plurality of heat exchange fins 11 are applied in a a known manner.

Each of the pipes 12 ends at the upper part with a first end segment 12a and a second end segment 12b, parallel to the first, both of which are inserted into the head 14 as will be described hereafter.

The head 14 comprises a connection element 21 made of plastic material, with a substantially prismatic shape and provided with a plurality of cavities 30 made adjacent to each other, open toward the outside and in each of which a first hole 31 and a second hole 32 are respectively made, passing through the whole thickness (fig. 4).

In this form of embodiment, the first 31 and second holes 32 have substantially the same diameter as the pipes 12.

In the connection element 21, moreover, two through holes 33 are respectively made, with a diameter substantially equal to the diameter of the pipes 12, the functions of which will be described hereafter.

For each of the pipes 12 it is provided to insert the first end segment 12a into the second hole 32 of one of the cavities 30, while the second end segment 12b is inserted into a first hole 31 of another cavity 30 disposed adjacent to the previous one.

The pipes 12 disposed at the ends of the connection element 21 are inserted with the respective first 12a or second end segment 12b into the through holes 33, and will constitute respectively the entrance pipe segments and exit pipe segments for the heat-carrying fluid in transit. In the forms of embodiment shown in figs. 4, 5 and 6, the holes 31, 32 are each provided with respective flarings 35 which allow the pipes 12, when they are inserted into the holes 31, 32, to be suitably deformed, for example by a socketing operation, to define collars 18 of different shapes and sizes (fig. 4) which attach the end segments 12a, 12b of the pipe 12, at the same time creating a hydraulic seal. The hydraulic seal can also be obtained by means of resins or by the socketing operation itself, or by combining two or more of said methods.

For example, before the insertion of the pipes 12 into the holes 31, 32, it may be provided to spread glue both in the holes 31, 32 and also at least on the parts of the pipe 12 that will go into contact with the holes 31, 32, so as to block the movement of the pipes 12 with respect to the connection element 21 and guarantee the hermetic seal and the solidarity of the pipes 12 with the connection element 21.

The head 14 also comprises a panel 22 that is located above the connection element 21 to close the cavities 30 and thus define a plurality of connection channels 16.

The panel 22 can be made of various materials on condition that it keeps its hydraulic seal, and can be associated with the connection element 21 with suitable attachment means or by gluing.

According to a variant, it may be provided that the connection channels 16 are made wholly or partly in the covering panel 22.

In fig. 5, a toric ring 19 is provided in the holes 31 and/or 32, which allows to obtain in the pipe 12 an annular deformation 20 that axially clamps the pipe 12 and improves the hydraulic seal.

According to another form of embodiment (fig. 6), instead of providing a panel 22 for closing the cavities 30, each of the latter is closed hydraulically by a closing stopper 23.

According to other forms of embodiment (figs. 7 and 8), it may be provided that the end segments 12a, 12b of the pipes 12, once inserted into the respective holes 31, 32, protrude from the cavity 30 and are drowned with their protruding portion in a layer of glue or resin 37 which guarantees both the mechanical and also the hydraulic seal thereof. The holes 31, 32 and the cavity 30 therefore define a through hole into which the pipes 12 are inserted; the pipes 12 have two different diameters, that is, a glass-type conformation provided with a first cylindrical portion and a second cylindrical portion with a diameter smaller than the first portion.

In the form of embodiment in fig. 7, the pipes 12 are inserted with a slight interference into the respective holes 31, 32 so that a closed zone is defined for containing the layer of glue or resin 37.

In the form of embodiment in fig. 8, on the contrary, the holes 31, 32 have a bigger diameter than that of the pipes 12 and the cavity 30 is closed at the lower part with another closing panel 39 or a packing which contains the glue distributed in the cavity 30.

According to another form of embodiment (fig. 9), the holes 31, 32 have a bigger diameter than that of the pipes 12 and a packing 40 is inserted into them that surrounds the end segments 12a, 12b of the pipes and affects at least part of the cavity 30; it is also interposed between the connection element 21 and the fins 11. The packing 40 has both the function of making the pipes 12 solid with the connection element 21, and also that of guaranteeing the hydraulic seal of the heat-carrying fluid in transit in the connection channel 16.

To this purpose the packing 40 may be made solid with the connection element 21 with glues or resins and has portions protruding from the edges of the holes 31, 32.

According to another form of embodiment (fig. 10), the connection element 21 is provided with holes 31, 32 that end flared at the upper part, to accommodate the collar 18 of the end segments 12a and 12b of the pipes 12.

A hydraulic seal packing 42 is disposed above the connection element 21, shaped so as to have at least a flat base or surface that is disposed above the surface of the connection element 21, and a plurality of raised and protruding elements 43, in this case shaped like a truncated cone, and configured to be inserted into the flared portions of the holes 31, 32. The protruding elements 43 of the hydraulic seal packing 42 are axially holed to accommodate the pipes 12, so as to position inside them the end segments 12a, 12b of the pipes 12, in order to make them solid with the connection element 21 and to achieve the hydraulic seal at least on the side facing toward the fins 1 1.

An intermediate element 46 is disposed above the hydraulic seal packing 42, provided, near each of the protruding elements 43, with a protruding annular edge 47 which, when in place, surrounds the through hole made in the protruding element 43.

When in use, the intermediate element 46 is pressed against the connection element 21 so that the protruding annular edge 47 presses against the hydraulic seal packing 42, thus guaranteeing the seal.

The intermediate element 46 is also provided with a through cavity 130 which connects the first 31 and the second hole 32, so as to define the connection channel 16 when the panel 22 is put above the intermediate element 46.

Another hydraulic seal packing 49 is interposed between the panel 22 and the intermediate element 46.

According to a variant, it may be provided that the intermediate element 46 and the panel 22 are made in a single body; in this way the presence of the hydraulic seal packing 49 is not necessary.

In another form of embodiment (fig. 11), the head is indicated by the reference number 114 and comprises a connection body, or element 121 to which, in the same way as described above, the passage pipes 12 of a heat-carrying fluid are connected, a covering panel 122 disposed above and which obtains the fluid- dynamic connection between the first 12a and the second end segment 12b of the pipes 12, and a hydraulic seal panel 142 interposed between the connection body 121 and the panel 122.

Both the connection body 121 and the panel 122 are made of plastic material. In other forms of embodiment, the connection body 121 and the panel 122 are made of shaped metal sheet.

The connection body 121 is provided with a plurality of first holes 131 and second holes 132 made through through its thickness, and through which the first 12a and the second end segment 12b of the pipes 12 are respectively able to be inserted.

Each of the first holes 131 and the second holes 132 has at least one part, in this case the whole thickness, that is conical in shape, with a conicity diverging toward the panel 122, that is, with a more ample size toward the latter.

The connection body 121 also has a housing seating 160 in which the hydraulic seal panel 142 is accommodated. The hydraulic seal panel 142 comprises a flat portion 144 with a substantially rectangular shape and a plurality of pre-molded hydraulic seal elements 143 made in a single body with the flat portion 144.

The hydraulic seal elements 143 are disposed on the flat portion 144 in a position mating with said first 131 and second holes 132, to be inserted into them through profile association.

The hydraulic seal elements 143 have a truncated cone conformation and a conicity that narrows toward the outside, that is, diverging, with a bigger size toward the covering panel 122. Each hydraulic seal element 143 has a shape mating with that of the first 131 and second holes 132 of the connection element 121.

Each of the hydraulic seal elements 143 is provided with a through hole 161 into which the first 12a and the second end segments 12b of the pipes 12 are directly inserted.

It is advantageous to provide that the hydraulic seal panel 142 is made of a material that is at least partly elastic, for example deformable polymer material, due to the effect of the heat-carrying fluid that acts upon it. In some forms of embodiment, the deformation of the hydraulic seal elements 143 is in the elastic field. Some forms of embodiment provide that the deformation to which the hydraulic seal panel 142, and hence the hydraulic seal elements 143, is subjected is in any case within the elastic field, thus guaranteeing the sealing effect.

Some forms of embodiment provide that the first 12a and second end segments 12b are made solid with the head 1 14, not only due to the mechanical action of the hydraulic seal panel 142 but also by means of glues.

The flat portion 144 of the hydraulic seal panel 142, in the surface where the hydraulic seal elements 143 are made, is provided with a first ridge 162 that extends on the perimeter in correspondence with the peripheral edges of the hydraulic seal panel 142.

The first ridge 162 is configured to be inserted into a mating groove 163 made in the housing seating 160.

In other forms of embodiment, for example the one shown in fig. 13, the hydraulic seal panel 142 has a second ridge 164 made on the opposite surface to that on which the first ridge 162 is made. Like the first ridge 162, the second ridge 164 also extends on the perimeter in correspondence with the peripheral edges of the hydraulic seal panel 142.

In the form of embodiment shown in fig. 15, the hydraulic seal panel 142 is only provided with the second ridge 164.

Both the first 162 and the second ridge 164 allow to increase the sealing effect of the hydraulic seal panel 142, and during use they are kept compressed by closing the connection body 121 and the panel 122 under pressure.

The panel 122 comprises a plate 165 which, during use, is put to rest and compressed against the hydraulic seal panel 142 and the connection body 121. The plate 165 is provided with a plurality of holes 166 (figs. 11 and 14) with an elongated shape and in correspondence with which shells 167 are made that define in turn connection channels 1 16. In fact, both the holes 166 and the shells 167 are disposed in an organized form, that is, according to a configuration adapted to the pattern in which the first 131 and second holes 132 of the connection body 121 are made, and each of them provides to connect one of the first end segments 12a of one pipe 12 with one of the second end segments 12b of another pipe 12. In this way, when associated with the connection body 121, the panel 122 achieves the fluid-dynamic connection between the end segments of the pipes 12, achieving the fluid-dynamic circuit in which the heat-carrying fluid, for example a cooling gas, is made to flow.

The shells 1 7 can be made protruding with respect to the plate 165 (fig. 14), or may be completely incorporated in its thickness (figs. 15 and 16).

In this latter case, the plate 165 is provided with the connection channels 1 16 made completely in its thickness.

Some forms of embodiment (figs. 1 1 and 14) provide that the connection channels 116 have an arched conformation. This conformation allows to considerably reduce the skin friction of the heat-carrying fluid in transit, thus increasing the heat exchange efficiency of the heat exchanger 10.

In its contact surface with the hydraulic seal panel 142, the plate 165 is provided with a first protuberance 168 (figs. 1 1, 17 and 18) conformed as a frame and which extends near the perimeter edges of the plate 165.

In particular, the first protuberance 168 during use is disposed so as to act directly on the hydraulic seal panel 142, exerting upon it a compression action and preventing the occurrence of leakages of heat-carrying fluid between the connection body 121 and the panel 122.

With reference to fig. 15, the first protuberance 168 is suitable to act externally with respect to the second ridge 164 and in fig. 16 the first protuberance 168 is configured to act in correspondence with the first ridge 162 so as to compress it inside the groove 163.

According to another form of embodiment (figs. 1 1, 15, 16 and 18), in its contact surface with the hydraulic seal panel 142, the plate 165 is provided with a plurality of second protuberances 169, each of which extends on the outside and on the perimeter of the corresponding hole 166 of the plate 165. The second protuberances 169 also exert on the hydraulic seal panel 142 an action of compression to increase the effect of fluid-dynamic seal.

The second protuberances 169 are also each disposed in correspondence with one of the hydraulic seal elements 143 to exert upon it an action of compression. In this case, given the truncated cone conformation of the first holes 131, second holes 132 and hydraulic seal elements 143, the action of compression exerted by the second protuberances 169 compresses the hydraulic seal elements 143 against the holes 131, 132. The first 12a and second end segments 12b are therefore compressed by the hydraulic seal elements 143, thus achieving both a hydraulic seal action and also a mechanical seal between the pipes 12 and the hydraulic seal panel 142.

The panel 122 is also provided with entrance holes 170 (fig. 14) and exit holes 171, through which the delivery and exit segments of the pipes 12 are made to pass. It is quite obvious that the forms of embodiment described above concerning the first 131 and second holes 132 also apply equally to the entrance holes 170 and exit holes 171 of the panel 122.

The panel 122 and the connection body 121 are associated under pressure with each other by interposing the hydraulic seal panel 142 by means of attachment means 172 (fig. 1 1).

The attachment means 172 can comprise a C-shaped brace 173 (in fig. 1 1 the attachment means are disposed on the left) which acts along the edges of the panel 122 and the connection body 121, or a snap-in connection element 174 present in the panel 122, or respectively in the connection body 121, and suitable to be inserted in a seating 175 made in the connection body 121 or respectively in the panel 122 (in fig. 1 1 the attachment means are disposed on the right). It is quite obvious that, in other forms of embodiment, other types of attachment means may be provided, such as for example attachment with threaded means, rivets, pins or other means chosen also depending on the working pressures that can be reached.

In some forms of embodiment (figs. 12, 14, 17 and 18) the panel 122, the hydraulic seal panel 142 and the connection body 121 are provided on the perimeter with a plurality of attachment holes 176 through which rivets, screws or other attachment means can be inserted to increase the sealing action of the attachment means 172.

Both the hydraulic seal panel 142 and the panel 122 are made of suitable polymer material, compatible with the type of heat-carrying fluid, or cooling gas, which is made to circulate through the heat exchanger 10.

In order to make the heat exchanger panel 142, the panel 122 and the connection body 121, a mold and a counter-mold are used, into which the polymer material is injected.

Some forms of embodiment provide to use a modular type mold, that is, with modules that are removed or added according to the number of pipes that make up the heat exchanger 10.

With reference to fig. 19, an injection molding apparatus is shown, used to make the panel 122, and indicated in its entirety by the reference number 180. It is quite obvious that a similar apparatus can be provided with suitable modifications to make the connection body 121 and the hydraulic seal panel 142. The apparatus 180 comprises a box-like mold 181 and a counter-mold 182 suitable to be inserted into the mold.

The mold 181 is provided with an injection cavity 189, in this case rectangular, and which during use is closed at the top by the counter-mold 182. The counter-mold 182 (figs. 19 and 20) comprises a plate 183 provided with a plurality of through holes 184 suitable to allow the attachment, for example by means of threaded connection means, of a plurality of shaped masses.

In particular, first shaped masses 185 are provided which reproduce in negative the shape of the connection channels 116, second shaped masses 186 which reproduce in negative the shape of the entrance holes 170 and exit holes 171 of the panel 122, third shaped masses 187 which reproduce in negative the attachment holes 176 of the panel 122, and fourth shaped masses 188 which define spacer elements between the mold 181 and the counter-mold 182.

The shaped masses 185, 186, 187 and 188 are associated to the plate 183 according to the pattern defined by the particular requirements of the application.

In order to reduce the complexity of the operations to assemble the counter- mold 182, it is possible to provide suitable masks suitable to keep the shaped masses 185, 186, 187 and 188 in position during their attachment.

It is clear that modifications and/or additions of parts may be made to the heat exchanger 10 as described heretofore, without departing from the field and scope of the present invention.

For example it may be provided that, instead of using U-shaped pipes 12, the pipes can be substantially rectilinear and have their respective ends that connect to a corresponding connection element 21, 121 and panel 22, 122 of the above type to achieve a head 14, 114 as described above.

Furthermore, in another form of embodiment (fig. 21), it may be provided that the hydraulic seal elements 143 are independent from the flat portion 144 of the hydraulic seal panel 142. In other words, a plurality of hydraulic seal elements 143 are provided, each of which is inserted into a respective first or second hole 131, 132.

Each of the hydraulic seal elements 143 has a truncated cone shape (in this case shown on the right in fig. 21), and is provided with an axial hole 161 into which during use an end segment 12a, 12b of the pipes 12 is inserted.

According to a variant, shown on the left in fig. 21, the hydraulic seal elements 143 are cylindrical in shape, provided with two diameters, that is, they have a first cylindrical part 145 with a smaller diameter than a second cylindrical part 146 which is associated in a single body with the first cylindrical part 145. In this case too, the hydraulic seal element 143 is provided with an axial hole 161 for the insertion, during use, of end segments of the pipes 12. The holes 131, 132 of the connection element 121, configured to accommodate the hydraulic seal elements 143, have a conformation mating with the latter. In other words, each of the hydraulic seal elements 143 is suitable to be positioned, through profile association, in the holes 131, 132. For this form of embodiment too it is possible to provide the same conformations of the panel 122 and the connection element 121 which were described above for the other forms of embodiment.

It is also clear that, although the present invention has been described with reference to some specific examples, a person of skill in the art shall certainly be able to achieve many other equivalent forms of heat exchanger 10, having the characteristics as set forth in the claims and hence all coming within the field of protection defined thereby.

Claims

1. Heat exchanger comprising a plurality of pipes (12) and at least a head (14; 1 14) into which end segments (12a, 12b) of the pipes (12) are inserted and a plurality of connection channels (16; 116) are made, each of which is configured to fluidically connect at least two of said end segments (12a, 12b) of the pipes (12) so as to define all in all a fluid-dynamic circuit for the passage of a heat- carrying fluid, characterized in that said head (14; 1 14) comprises:

- a connection element (21; 121) provided with a plurality of holes (31, 32; 131, 132), shaped at least partly like a truncated cone, or at least partly cylindrical provided with two diameters, in which the end segments (12a, 12b) of said pipes (12) are disposed,

- a covering panel (22; 122) in which said connection channels (16; 1 16) are made,

- pre -molded hydraulic seal elements (143), suitable to be positioned through profile association in said holes (31, 32; 131, 132) present in the connection element (21; 121) and through which the end segments (12a, 12b) of said pipes (12) are disposed.

2. Heat exchanger as in claim 1, characterized in that said hydraulic seal elements (143) have a larger size toward said covering panel (122).

3. Exchanger as in claim 1 or 2, characterized in that at least some of said hydraulic seal elements (143) are deformable due to the effect of the pressure of the heat-carrying fluid.

4. Exchanger as in claim 3, characterized in that said deformation is in the elastic field.

5. Exchanger as in any claim hereinbefore, characterized in that said hydraulic seal elements (143) are associated with a flat portion (144) to define a hydraulic seal panel (142) interposed between said connection element (121) and said covering panel (122), each of said hydraulic seal elements (143) being provided with a through hole (161) for the insertion of an end segment (12a, 12b) of said pipe (12).

6. Exchanger as in claim 5, characterized in that said flat portion (144) is provided with at least a ridge (162, 164) which extends on the perimeter near its peripheral edge.

7. Heat exchanger as in claim 6, characterized in that at least one of either said connection element (121) and said covering panel (122) is provided with a groove (163) configured to accommodate said ridge (162).

8. Exchanger as in any claim hereinbefore, characterized in that said covering panel (122) comprises a plate (165) provided with a plurality of holes (166), and a plurality of shells (167) made in correspondence with said holes (166), in a single body with said plate (165), and defining with said holes (166) said connection channels (116) with an arched shape.

9. Heat exchanger as in any claim hereinbefore, characterized in that said covering panel (122) is provided with a first protuberance (168) conformed as a frame and which extends near its perimeter edges.

10. Heat exchanger as in any claim hereinbefore, characterized in that said covering panel (122) is provided with a plurality of second protuberances (169) each of which extends on the perimeter of one of said connection channels (116) and is configured to compress said hydraulic seal elements (143) toward said holes (131, 132) of the connection element (121).

1 1. Heat exchanger as in any claim hereinbefore, characterized in that it comprises attachment means (172) configured to put under compression said hydraulic seal elements (143) between said covering panel (122) and said connection body (121).

12. Exchanger as in any claim hereinbefore, characterized in that said covering panel (122) and said connection element (121) are made of polymer material.

13. Hydraulic seal element shaped like a truncated cone and provided with an axial hole (161) suitable to accommodate a pipe (12) of a heat exchanger (10) as in any claim hereinbefore.

14. Hydraulic seal element with a cylindrical shape having at least two diameters and provided with an axial hole (161) suitable to accommodate a pipe (12) of a heat exchanger (10) as in any claim from 1 to 13.

15. Hydraulic seal element as in claim 13 or 14, characterized in that it is made of an at least partly elastic material.

16. Hydraulic seal panel having a plurality of hydraulic seal elements (143) as in any claim from 13 to 15, associated with a flat portion (144) and disposed in an organized form.

17. Hydraulic seal panel as in claim 16, characterized in that said flat portion (144) is provided with at least a ridge (162, 164) that extends on the perimeter near its peripheral edge.

18. Covering panel provided with a plurality of connection channels (1 16) suitable to reciprocally connect at least two pipes (12) of a heat exchanger (10) as in any claim hereinbefore.

19. Covering panel as in claim 18, characterized in that it comprises a plate (165) provided with a plurality of holes (166), and a plurality of shells (167) made in correspondence with said holes (166), in a single body with said plate (165), and defining with said holes (166) said connection channels (116) with an arched shape.

20. Connection element provided with a plurality of holes (31, 32; 131, 132) shaped at least partly like a truncated cone or at least partly cylindrical and provided with two diameters, suitable to accommodate hydraulic seal elements (143) as in any of claims 13 or 14 and through which end segments (12a, 12b) of pipes (12) of a heat exchanger (10) as in any claim from 1 to 13 are inserted.