WO2019145556A1

WO2019145556A1 - Heat exchanger plate

Info

Publication number: WO2019145556A1
Application number: PCT/EP2019/052095
Authority: WO
Inventors: Gaël DURBECQ
Original assignee: Valeo Systemes Thermiques
Priority date: 2018-01-29
Filing date: 2019-01-29
Publication date: 2019-08-01
Also published as: FR3080174A1; FR3080174B1

Abstract

Heat exchanger (1) plate (2) comprising at least one hole (34), the hole (34) being surrounded by a collar (48), the collar (48) comprising a top (16), characterized in that a first plane (17) in which the top (16) of the collar (48) extends and a second plane (18) in which the hole (34) extends are separate. The invention is for use in the automotive field.

Description

HEAT EXCHANGER PLATE

The field of the present invention is that of heat exchangers, which are particularly intended to be provided on air conditioning loops of motor vehicles.

The heat exchangers provided on air conditioning loops of vehicles are arranged to allow the adjacent circulation, in two separate spaces , of two different fluids, such as to produce a heat exchange between the fluids without mixing them . A type of heat exchanger used, inter alia, in the automotive field is the plate exchanger, this exchanger being made up of a stack of plates brazed together and arranged to define the spaces in which the fluids circulate . These plates most frequently comprise a device for disrupting the flow of a fluid along one of the sides of the plate .

These plates are dimensioned to be in close contact with one another before the brazing step . However, due to the existence of manufacturing tolerance, the stack of the plates does not guarantee optimum contact between the plates, and therefore optimum brazing . This brazing fault causes leaks between the fluid circuits , or an insufficient mixture within a same circuit, which reduces the effectiveness of the heat exchanger or renders it unusable .

Therefore, the aim of the present invention is to overcome the disadvantages described above by designing a plate for a heat exchanger having plates arranged to provide optimum brazing therebetween .

Therefore, the object of the invention is a heat exchanger plate comprising at least one hole, the hole being surrounded by a collar, the collar comprising a top, a first plane in which the top of the collar extends and a second plane in which the hole extends being separate .

This arrangement makes it possible to ensure that the plates are properly in contact with one another, thus providing the sealing of the circuits of fluids circulating in the heat exchanger at the openings and the collars , and an optimum mixture of the fluids which circulates therein by guaranteeing perfect contact of the disrupting devices .

The plate according to the invention advantageously comprises any one of the following features at least, which are taken separately or in combination :

- the second plane, in which the hole extends , is the extension plane of the hole, i.e. passing through the hole, at equal distance from an upper side of the part of the plate defining the hole and from a lower side of the part of the plate which defines the hole . The first plane, in which the top of the collar extends, is the plane defined by all of the end points of the collar, i.e. the points of the collar that are furthest away from the plate, taken perpendicular to a general extension plane of the plate,

a distance between the first plane and the second plane, in a direction perpendicular to the second plane, is between 0.01 and 0.4 millimetres ,

- the plate comprises a device for disrupting a fluid that can flow along the plate . The disrupting device of the plate comprises a plurality of grooves , which are arranged in the shape of a "V" and the arms of which are parallel with one another . The disrupting device is arranged to disrupt the flow of a fluid that can flow along the plate, advantageously of two fluids which each flow on either side of the plate, the plate has a tub general shape and comprises a bottom surrounded by a closed and raised peripheral edge forming the tub, the disrupting device extending in the bottom of the plate . The peripheral edge is continuous , i.e. it forms only a single peripheral edge extending over the entire periphery of the bottom of the plate, a height of the disrupting device is less than a height of the collar. The height of the disrupting device is the dimension of the disrupting device measured in a vertical direction. The height of the disrupting device is measured between a third plane passing through two bases of grooves and a fourth plane passing through two crests of grooves, in a direction perpendicular to the third plane . The height of the collar is the dimension of the collar in a vertical direction . The height of the collar is measured between a plane defined by a lower side of the plate as far as the first plane, in which the top of the collar extends , in a direction perpendicular to the plane defined by the lower side of the plate,

the collar extends in a direction opposite the extension direction of the grooves of the disrupting device . The collar extends in the same direction or mainly the same direction as the peripheral edge of the plate,

the top of the collar has a rounded shape taken in a section perpendicular to a general extension plane of the plate and passing through the collar . Taken in the perpendicular section, the top of the collar has a "U" shape . According to an example, the collar, from the junction thereof with the plate as far as the hole by passing through the top thereof, only comprises one continuous side, without an edge,

the disrupting device extends from, i.e. from the point of, a lower side of the bottom of the plate, the disrupting device extends in a direction opposite the general extension direction of the peripheral edge . More specifically, at least one groove of the disrupting device extends in a direction opposite the general extension direction of the peripheral edge . Advantageously, all of the grooves of the disrupting device extend in a direction opposite the general extension direction of the peripheral edge,

the disrupting device and the collar consist of a single piece with the plate bearing them, i.e. the plate, the collar and the disrupting device are integral, the disrupting device and the collar being formed by deformations of a constituent sheet of the plate,

- the disrupting device is manufactured by punching or rolling,

the collar is arranged to deform in a direction perpendicular to a general plane of the plate . More particularly, it is the rounded shaping of the collar which allows it to roll over the bottom of the adjacent plate and therefore to deform in order to provide the required sealing,

- the collar is continuous completely around the hole that it surrounds, i.e. the height of the collar surrounding the hole is continuous over the entire length of the collar .

The invention also relates to a tube for circulation of a fluid comprising a first plate and a second plate, at least the first plate being a plate as described above, the second plate being fitted into the first plate, the top of the collar of the first plate being in contact with a bottom of the second plate .

The circulation tube according to the invention advantageously comprises at least any one of the following features , taken in isolation or in combination :

the contact between the top of the collar of the first plate and the bottom of the second plate occurs more specifically on a lower side of the bottom of the second plate,

a height of the collar of the first plate is greater than a height of the disrupting device of the second plate . The height of the collar of the first plate can thus be greater than the height of the disrupting device of the second plate by 0.01 millimetres to 0.05 millimetres,

a height of the collar of the second plate is greater than a height of the disrupting device of the first plate,

the disrupting device of the second plate is in contact with the bottom of the first plate,

- the disrupting device comprises a crest, the crest of the disrupting device of the first plate being in contact with the bottom of the second plate, the first plate and the second plate are brazed together . The interface between the collar of the first plate and the bottom of the second plate offers a deposit surface that is particularly suitable for a deposit of brazing flux, facilitating and improving the brazing of the plates with one another . The flux deposit is further improved by the interface between the rounded shape of the collar and the planar shape of the bottom of the plate,

the tubs of the plates are fitted into one another . The upper side of the first plate is facing the lower side of the second plate, the 1ower side of the first plate facing the upper side of a third plate, adjacent to the first plate and in which the first plate is fitted .

The invention also relates to a heat exchanger comprising a plurality of plates as described above, the plates being fitted into one another, at least a first pair of plates, comprising a first plate and a second plate, defining a first circulation circuit that can be taken by a first fluid and at least a second pair of plates, comprising the first plate and a third plate, defining a second circulation circuit that can be taken by a second fluid .

Advantageously, the invention relates to the use of such a heat exchanger as a condenser or a cooler for gas . Advantageously, the invention relates to the use of the heat exchanger wherein the first fluid is a heat-transfer liquid and the second fluid is a refrigerant. The heat exchanger is then a gas/liquid or liquid/liquid heat exchanger, depending on the state of the refrigerant during the journey thereof in the heat exchanger .

The invention finally relates to a refrigerant circuit comprising at least an expansion member, an evaporator, a compressor and a heat exchanger as is described above, which are crossed by a refrigerant and by a heat-transfer liquid .

Other features, details and advantages of the invention will emerge more clearly upon reading the description given hereafter in an indicative manner with reference to the drawings wherein :

- Figure l is a general view, in perspective, of a heat exchanger according to the invention,

- Figure 2a is a perspective view of a first plate according to the invention, Figure 2b being a perspective view of a second plate according to the invention,

- Figure 3 is a sectional view of a plate according to the invention, particularly illustrating the layout of a collar and of a disrupting device which are arranged on the plate, according to a plane OLV passing through the collar and visible in Figure 2 , and

- Figure 4 is a detail of a sectional view of a stack of two plates according to the invention, particularly the interaction between the top of a collar and an immediately adjacent plate .

It must firstly be noted that the figures disclose the invention in a detailed manner in order to implement the invention, wherein said figures can, of course, be used to better define the invention when required .

In the remainder of the description, the terms longitudinal, vertical or transversal , top, bottom, front and rear refer to the orientation of the heat exchanger according to the invention . The longitudinal direction corresponds to the main axis of the heat exchanger in which the largest dimension thereof extends . The vertical direction corresponds to the stacking direction of the plates making up the heat exchanger, the transversal direction being the direction perpendicular to the other two directions . The longitudinal, transversal and vertical directions are also visible in a trihedron L, V, T shown in the figures .

Figure 1 shows , in perspective, a heat exchange module 3 formed by the combination of a separation member 56 rigidly connected to a heat exchanger 1 according to the invention .

The heat exchanger l is a component of a refrigerant circuit which is provided on a vehicle, particularly a motor vehicle . According to the invention, the heat exchanger 1 implements an exchange of calories between a first fluid and a second fluid, the second fluid then being cooled by the first fluid . In such a configuration, the heat exchanger 1 is used as a condenser for a subcritical or supercritical refrigerant . The other circulating fluid is advantageously a heat-transfer liquid, such as a water/glycol mixture .

The heat exchanger 1 comprises a core 6 where the heat exchange between the first fluid and the second fluid takes place . The core 6 is generally formed by a stack of plates, superposed on one another along a stacking direction 7 of these plates 2. The core 6 particularly comprises a first wall 50 and a second wall 52 which define the core 6 along the stacking direction 7. The plurality of plates is laid out between the first wall 50 and the second wall 52 , which plurality of plates defines two separate circuits : a first circuit 4 arranged such as to be crossed by the first fluid and a second circuit 8 configured to be crossed by the second fluid .

The heat exchanger 1 furthermore comprises means for linking these circuits with firstly a circuit of the first fluid external to the heat exchanger 1 and secondly with a circuit of the second fluid external to the heat exchanger 1. The heat exchanger 1 thus comprises a first sleeve 68 via which the first fluid can enter the heat exchanger 1 and a second sleeve 70 via which the first fluid can exit the heat exchanger 1. This heat exchanger

1 further comprises a third sleeve 72 via which the second fluid can enter the core 6, and a fourth sleeve 74 via which the second fluid can exit the core 6. It will be noted that the core 6 comprises a first opening and a second opening through which the second fluid flows and which are in communication with a seat 57 fluidly inserted between the heat exchanger 1 and the separation member 56, the separation member being mechanically borne by the seat 57. The seat 57 is thus part of the heat exchange module 3.

The heat exchanger 1 comprises a first longitudinal end 40 and a second longitudinal end 42 , the first longitudinal end 40 being opposite the second longitudinal end 42 with respect to a central portion 43 of the heat exchanger .

The heat exchanger 1 according to the invention thus comprises a set of plates 2 stacked upon one another in order to form the circuits of the heat exchanger 1. An example of a plate 2 is illustrated in Figure 2. Two immediately adjacent plates 2 define a circulation tube where the first fluid or the second fluid can circulate . The circulation tubes arranged for the circulation of the first fluid, called the first circulation tube, alternate with the ducts arranged for the circulation of the second fluid, called the second circulation tube . Thus, a first plate 2a can be arranged for the circulation of the first fluid in conjunction with a second adjacent plate 2b, and can be arranged for the circulation of the second fluid in conjunction with a third adjacent plate 2c. A same plate 2 is thus lapped on one side by the first fluid and on the other by the second fluid .

In the remainder of the description, the term plate

2 equally designates a first plate 2a, a second plate 2b or a third plate 2c.

As can be seen in Figure 2 , each plate 2 has the shape of a tub, i.e. it comprises a bottom 20 , surrounded by a peripheral edge 22. The bottom 20 of the plate 2 has a shape of a rectangle with rounded corners. The peripheral edge 22 surrounding the bottom 20 extends continuously entirely around the plate 2, without interruption .

The peripheral edge 22 comprises an inner side 24 and an outer side 26, the outer side 26 being opposite the inner side 24. The bottom 20 is defined by an upper side 30 and a lower side 32, the upper side 30 being the side from which the peripheral edge 22 rises, the lower side 32 being the side of the plate 2 opposite the upper side 30. The inner side 24 of the peripheral edge 22 is a continuation of the upper side 30 of the bottom 20 of the plate 2.

The peripheral edge 22 is flared, i.e. the perimeter of the part of the peripheral edge 22 in contact with the bottom 20 is less than the perimeter at the free part 28 thereof, the free part 28 being the part opposite the part in contact with the bottom 20

The plates 2 are stacked, one in the other, the upper side 30 of a first plate 2a facing the lower side 32 of a second adjacent plate 2b. Likewise, the lower side 32 of the first plate 2a faces the upper side 30 of a third plate 2c adjacent to the first plate 2a.

The plates 2 are manufactured by punching, stamping or rolling a strip of a material arranged to allow heat exchanges sufficient to permit the heat exchanger 1 to fulfil the function thereof . This can particularly be aluminium or an aluminium alloy .

The plates 2 comprise a disrupting device 100 for the flow of at least one of the fluids, and advantageously for the two fluids which can cross the heat exchanger . The plates 2 comprise a first transversal end 44 , a second transversal end 46 opposite the first transversal end 44 with respect to the disrupting device 100, a first longitudinal end 40 and a second longitudinal end 42 opposite the first longitudinal end 40 with respect to the disrupting device 100. Each plate 2 comprises at least one hole 34. In the example of the invention, the plates 2 include four holes 34, laid out at each of the corners of the plate 2. The plates thus include a first hole 34a, a second hole 34b, a third hole 34c and a fourth hole 34d. The holes 34 have a circular shape . The holes 34 are through-holes . These holes 34 are arranged to allow passage of the first fluid or of the second fluid .

The first hole 34a and the second hole 34b are arranged to allow the circulation of the first fluid . The third hole 34c and the fourth hole 34d are arranged to allow the circulation of the second fluid .

The plates 2 are differentiated into a first plate 2a, a second plate 2b and a third plate 2c.

On the first plate 2a, illustrated in Figure 2a, the first hole 34a is laid out at the corner of the first longitudinal end 40 and of the first transversal end 44. The second hole 34b is laid out at the corner of the second longitudinal end 42 and of the first transversal end 44. The first hole 34a and/or the second hole 34b are laid out at the end of a collar 48. The collar 48 comprises a top 16. The top 16 of the collar 48 is intended to be in contact with the lower side 32 of a second adjacent plate 2b. When the collar 48 is in contact with the lower side 32 of the second adjacent plate 2b, it prevents the circulation of the first fluid in the circulation tube intended for the second fluid .

The third hole 34c is laid out at the corner of the first longitudinal end 40 and of the second transversal end 46. The fourth hole 34d is laid out at the corner of the second longitudinal end 42 and of the second transversal end 46. The third hole 34c and/or the fourth hole 34d are arranged in the bottom 20 of the plate 2 , i.e. a plane in which the third hole 34c and/or the fourth hole 34d extends is merged with the plane in which the bottom 20 of the plate 2 extends .

On the second plate 2b, illustrated in Figure 2b, the first hole 34a is laid out at the corner of the first longitudinal end 40 and of the second transversal end 46. The second hole 34b is laid out at the corner of the second longitudinal end 42 and of the second transversal end 46. The first hole 34a and/or the second hole 34b are laid out at the end of a collar 48. The collar 48 is intended to be in contact with the lower side 32 of a first adjacent plate 2a. When the collar 48 is in contact with the lower side 32 of the first adjacent plate 2a, it prevents the circulation of the second fluid in the circulation tube intended for the first fluid .

The third hole 34c is laid out at the corner of the first longitudinal end 40 and of the first transversal end 44. The fourth hole 34d is laid out at the corner of the second longitudinal end 42 and of the first transversal end 44. The third hole 34c and/or the fourth hole 34d are arranged in the bottom 20 of the plate 2 , i.e. a plane in which the third hole 34c and/or the fourth hole 34d extends is merged with the plane in which the bottom 20 of the plate 2 extends .

The third plate 2c is arranged identically with respect to the second plate 2b.

Irrespective of the plate 2 in question, and seen in the plane OLV illustrated in Figure 2a, the collar 48 has a rounded shape, i.e. the collar 48 is bulged . This layout is more specifically illustrated in Figure 3. Thus, the top 16 of the collar is laid out as a continuation of the collar 48. In other words, there is no sharp edge between the top 16 and a base of the collar 48.

The collars 48 consist of a single piece with the plates 2 , i.e. they form a single block of material with the plate 2 in which they are formed . The collar 48 results from the method for manufacturing the plate 2 , and is , for example, punched at the same time as the other shapes provided on the plate 2.

In this layout , a first plane 17 in which the top 16 extends is separate from a second plane 18 in which the hole 34 extends . The second plane 18 in which the hole 34 extends passes through the hole 34 , between an upper side 30 of the part of the plate 2 surrounding the hole 34, and a lower side 32 of the part of the plate 2 surrounding the hole 34. The second plane 18 in which the hole 34 extends and the first plane 17 in which the top 16 extends are parallel or mainly parallel, taking into account the manufacturing tolerances .

The height 14 of the collar 48 is the dimension of the collar 48 in a vertical direction, i.e. the direction perpendicular to a plane OLT passing through the bottom 20 of the plate 2. The height 14 of the collar 48 is measured between a plane passing through a lower side 32 of the plate 2 as far as the first plane 17 in which the top 16 of the collar 48 extends, in a direction perpendicular to a plane in which the lower side 32 of the plate 2 predominantly falls .

The plates 2 comprise at least the disrupting device 100, illustrated in Figures 2 and 3, and arranged to disrupt the circulation of the fluid or of the fluids circulating along the plates 2. This disrupting device 100 consists , for example, of a single piece with the plates 2 , i.e. it forms a single block of material with the plate 2 in which it is formed . The disrupting device 100 results from the method for manufacturing the plate 2 , and is , for example, punched at the same time as the plate 2.

The disrupting device 100 extends between firstly the first hole 34a and the third hole 34c and secondly the second hole 34b and the fourth hole 34d, i.e. over the entirety of the portion of the plates 2 which extends between the first longitudinal end 40 and the second longitudinal end 42.

This disrupting device 100 has the shape of chevrons, i.e. a series of grooves 104 given a "V" profile, when observed in a plane perpendicular to the extension plane of the plate 2. The grooves 104 are more particularly visible in Figure 2. This chevron layout can be seen in Figure 2. The direction of the chevrons is alternated from one plate 2 to another . The grooves 104 are given a "U" profile, seen in a cutting plane perpendicular to the extension plane of the plate 2 and parallel to the longitudinal direction L . This "U" shaped profile thus defines a base 108 and a crest 110. This layout is more particularly visible in Figure 3. The deformation of the disrupting device 100 during the manufacturing process occurs in the direction facing away from the tub of the plate 2, i.e. the disrupting device extends from the lower side 32 of the plate 2. The direction of this deformation is the same for each plate 2. During the stacking of the plates 2, at least one portion of the bases 108 of the grooves 104 of a second plate 2b enters into contact with a portion of the crests 110 of a first plate 2a arranged beneath the second plate 2b.

Each groove 104 is defined by a height 12 illustrated in Figure 3. The height 12 of a groove 104 is the dimension of the groove 104 in a vertical direction, i.e. the direction perpendicular to the plane OLT passing through the bottom 20 of the plate 2. The height 12 of a groove 104 is determined between a third plane passing through two bases 108 and a fourth plane passing through two crests 110, and is measured in a direction perpendicular to the third plane .

The height 12 of the grooves 104 is less than the height 14 of the collars 48. More particularly, the height 12 of the grooves 104 is 0.02 millimetres less than the height 14 of the collars 48. It will be understood that the difference is given in this case by way of example . This difference allows, when fitting a second plate 2b into a first plate 2a, the top 16 of the collar 48 of the first plate 2a to be in contact with the bottom 20 of the second plate 2b, thus guaranteeing a deformation of the collar .

The direction of the chevrons is alternated from one plate 2 to another . Thus, the point of the "V" of the grooves 104 of a first plate 2a is directed toward the first longitudinal end 40 , whereas the point of the "V" of the grooves 104 of a second plate 2b immediately adjacent to the first plate 2a is directed toward the second longitudinal end 42. The point of the "V" of the grooves 104 of a third plate 2c immediately adjacent to the first plate 2a is directed toward the second longitudinal end 42.

The grooves 104 are continuous over the entire length thereof, i.e. the height 12 thereof is constant from the first transversal end 44 of the plate 2 to the second transversal end 46 of the plate, with the exception of the ends of the grooves 104.

The deformation of the disrupting device 100 during the manufacturing process occurs in the direction facing away from the tub of the plate 2 , i.e. the disrupting device 100 extends from the lower side 32 of the plate 2. The direction of this deformation is the same for each plate 2. During the stacking of the plates 2 , at least one portion of the bases 108 of the grooves 104 of the first plate 2a enters into contact with a portion of the bottom 20 of the second plate 2b arranged beneath the first plate 2a in question . More particularly, a point of contact occurs between the base 108 of the second plate 2b and the crest 110 of the first plate 2a, between two grooves 104 of the first plate 2a.

A circulation tube comprises a plurality of points of contact . The crest 110 of each groove 104 of a first plate 2a has several points of contact with the base 108 of several grooves 104 of a second plate 2b. Likewise, the base 108 of each groove 104 of the second plate 2b has several points of contact with the crest 110 of several grooves 104 of the first plate 2a.

The base 108 of the grooves 104 of the second plate 2b is in contact with the bottom 20 of the first plate 2a. Contact takes place between the lower side of the base 108 of the second plate 2b and the upper side 30 of the bottom 20 of the first plate 2a, on the part of the upper side 30 between two grooves 104 of the first plate 2a. This contact is repeated over the entire length of the groove 104 of the second plate 2b, such that the base 108 of the groove 104 of the second plate 2b is in contact with the upper side 30 of the bottom 20 of the first plate 2a between a plurality of grooves 104 of the first plate 2a.

This contact, once the plates 2 have been brazed together, forms a bridge joining the two constituent adjacent plates of the circulation tube. Such a bridge disrupts the flow of the fluid between the two plates 2.

The first fluid is a heat-transfer liquid or a mixture between one or more heat-transfer liquids and one or more other fluids , the heat-transfer liquid or liquids being selected from the authorized heat-transfer liquids and suited to the use made thereof . The heat-transfer liquid or liquids are particularly water, deionized water, a mixture of glycol and of water or a dielectric liquid such as fluorocarbons .

The second fluid is a refrigerant or a mixture of one or more refrigerants and one or more other fluids, the refrigerant or refrigerants being selected from the authorized refrigerants and suited to the use made thereof . The refrigerant or refrigerants are particularly from the family of hydrochiorofluorocarbons (HCFC ) , or of hydrofluorocarbons (HFC) . The refrigerant can particularly be R134a or 1234YF . The refrigerant can also be carbon dioxide known by the acronym R744.

A method of manufacturing the heat exchanger 1 will now be described . This method example is given as a nonlimiting example, and alternative methods can be used to produce the heat exchanger 1 as described above .

The various plates 2 defining the heat exchanger 1 are stacked . A first plate 2a is laid out alternately with a second plate 2b, the stacking of these alternating plates 2 being between the first wall 50 and the second wall 52.

As disclosed above, when fitting a second plate 2b into a first plate 2a, the top 16 of the collars 48 of the first plate 2a is in contact with the bottom 20 of the second plate 2b. The plates 2 are then compressed, the collars 48 of the plates 2 deforming in a direction parallel to the stacking direction of the plates 2. More specifically, the collars 48 of a plate 2 deform in a direction orientated toward the bottom 20 of the plate 2. It is the rounded shaping of the collars 48 of the various plates 2 which allow this deformation . The collars 48 of a plate will thus roll against the bottom of the adjacent plate and deform. This deformation continues until the bases 108 of the grooves 104 of the second plate 2b are in contact with the crests 110 of the grooves 104 of the first plate 2a. Thus, the rounded shaping of the collars no longer represents a limitation to the contact between the bases 108 of the grooves 104 of the second plate 2b in contact with the crests 110 of the grooves 104 of the first plate 2a.

The first sleeve 68, the second sleeve 70 , the third sleeve 72 and the fourth sleeve 74 are then laid out .

All of the pieces laid out in the previous step are then brazed together, using a method of brazing by placing in an oven . A brazing flux is deposited on the pieces to be brazed, the brazing flux forming a deposit 60 at the interface between a collar 48 of a first plate 2a and a lower side 32 of a second plate 2b. The interface between the collar 48 and the lower side 32 , as well as the deposit 60 of brazing flux, are illustrated in Figure 4. The interface between the collar 48 and the lower side 32 of the plate 2 , due to the shape thereof, facilitates the deposit 60 of brazing flux . More specifically, the rounded shape of the collar 48 , in conjunction with the lower side 32 of plate 2 , creates a space allowing a larger and more stable deposit of brazing flux . The brazing flux is particularly deposited in two deposits 60 , a first deposit 60a and a second deposit 60b . The first deposit 60a occurs between the top 16 of the collar 48 of the first plate 2a, the lower side 32 of the second plate 2b and a space 61 between the two plates 2 where a fluid can flow . The second deposit 60b occurs between the top 16 of the collar 48 of the first plate 2a, the lower side 32 of the second plate 2b and the hole 34 of the two plates 2.

This brazing step will rigidly connect the various types of plates 2 together. The combination of the deformation of the collars 48 and the deposit 60 of brazing flux allows effective brazing, which guarantees sealing of the heat exchanger 1 via the contact between the top 16 of the collars 48 of a plate and the lower side 32 of the bottom of the adjacent plate, and an effective mixture of the fluids which circulates there via the contact between the base 108 of the grooves 104 and the bottom 20. The heat exchanger 1 is then connected to the loops of the various fluids .

The resulting heat exchanger 1 can operate according to the following example . This is not a limiting example, and other operations can be envisaged . These operations include the possibility of arranging the circuits such as to circulate the fluids therein using several passes .

The first fluid enters the heat exchanger 1 via the first sleeve 68. The first fluid circulates in the first circuit 4 toward the second sleeve 70 in a single pass . The circulation of the first fluid is disrupted by the disrupting devices 100. The first fluid is then evacuated out of the second sleeve 70 toward a loop for heat treatment of the first fluid . Along the entirety of this loop, the first fluid is in the liquid state and it exchanges calories with the second fluid .

The second fluid enters the heat exchanger 1 via the third sleeve 72. The second fluid can be in the gas state . The second fluid circulates in the second circuit 8 and transfers the calories thereof to the first fluid which circulates in the first circuit 4. This transfer of calories results in the second fluid being cooled, and the second fluid changes from the gas state to a gas- liquid two-phase state and then to a liquid state . The flow of the second fluid is disrupted by the disrupting devices 100 present in the second circuit 8. The second fluid passes through the separation member 56 before reaching the fourth sleeve 74 and being evacuated.

The description above clearly explains how the invention makes it possible to achieve the objectives set thereby and particularly to propose a heat exchanger plate arranged to facilitate and improve the contact between two plates .

Of course, various modifications can be made by a person skilled in the art to the plate, to the circulation tube or to the heat exchanger which have been described above by way of nonlimiting example, once a plate having a hole surrounded by a collar is used, the first plane in which a top of the collar extends being separate from the second plane in which the hole extends .

In any case, the invention cannot be limited to the embodiment specifically described in this document, and covers, in particular, all equivalent means and any technically effective combination of these means .

Claims

1. Heat exchanger (1) plate (2) comprising at least one hole (34), the hole (34) being surrounded by a collar

(48), the collar (48) comprising a top (16), characterized in that a first plane ( 17 ) in which the top (16) of the collar (48 ) extends and a second plane (18) in which the hole ( 34 ) extends are separate .

2. Plate (2 ) according to the preceding claim, comprising a device (100) for disrupting a fluid that can flow along the plate (2) .

3. Plate (2 ) according to the preceding claim, which has a tub general shape and comprising a bottom (20 ) surrounded by a closed and raised peripheral edge (22 ) forming the tub, the disrupting device (100) extending from the bottom (20) of the plate (2) .

4. Plate (2 ) according to any one of Claims 2 or 3, wherein a height ( 12 ) of the disrupting device ( 100 ) is less than a height ( 14 ) of the collar ( 48 ) .

5. Plate (2 ) according to any one of the preceding claims, wherein the disrupting device (100) comprises at least one groove (104) , the collar ( 48 ) extending in a direction opposite the extension direction of the groove (104) .

6. Plate (2 ) according to any one of the preceding claims, wherein the top (16) of the collar (48) has a rounded shape taken in a section perpendicular to a general extension plane of the plate (2) and passing through the collar ( 48 ) .

7. Plate (2) according to any one of Claims 2 to 6, wherein the disrupting device (100) and the collar (48) consist of a single piece with the plate (2) .

8. Plate (2) according to any one of the preceding claims, wherein the collar ( 48 ) is arranged to deform in a direction perpendicular to a general plane of the plate (2 ) .

9. Tube for circulation of a fluid comprising a first plate (2a) and a second plate (2b) , at least the first plate (2a) being in accordance with any one of the preceding claims, the second plate (2b) being fitted into the first plate (2a) , and the top (16) of the collar ( 48 ) of the first plate (2a) is in contact with a bottom (20) of the second plate ( 2b) .

10. Circulation tube according to the preceding claim, wherein a height (14 ) of the collar ( 48 ) of the first plate (2 ) is greater than a height (12) of the disrupting device (100) of the second plate (2) .

11. Heat exchanger (1) comprising a plurality of plates (2 ) according to any one of Claims 1 to 10 , the plates (2 ) being fitted into one another, at least a first pair of plates (2), comprising a first plate (2a) and a second plate (2b) , defining a first circulation circuit that can be taken by a first fluid and at least a second pair of plates (2), comprising the first plate (2a) and a third plate (2c) , defining a second circulation circuit that can be taken by a second fluid .

12. Use of a heat exchanger (1) according to the preceding claim as a condenser or a cooler for gas .

13. Use of a heat exchanger (1) according to Claim 11, wherein the first fluid is a heat-transfer liquid and the second fluid is a refrigerant. 14. Refrigerant circuit comprising at least one expansion member, an evaporator, a compressor and a heat exchanger (1) according to Claim 11 , which are crossed by a refrigerant and by a heat-transfer liquid .