FR2989768A1 - Beam for plates of heat exchanger e.g. supercharging air cooler, in air intake module for thermal engine of car, has bar located at exchange zone between two ends of stack of plates, so as to connect peripheral edge of plates - Google Patents

Abstract

The beam (7) has a stack of plates (10) for allowing heat exchange between a gas and a cooling fluid i.e. water added with glycol circulating in contact with the plates at an exchange zone (51). The plates include wings for guiding the gas, where the wings are situated at two opposite ends (81, 82) of the plates. A bar (100) extends between the plates, where the bar is located at the exchange zone between the two ends of the plates, so as to connect a peripheral edge (84) of the plates. A cover (25) maintains the stack of plates, where the bar is secured to the cover.

Description

Heat exchanger. The invention relates to a heat exchanger, in particular for a motor vehicle, such as for example an exchanger intended to be mounted in the engine compartment of the vehicle such as a charge air cooler (RAS) or a recirculation heat exchanger of the exhaust gases. engine exhaust, also called EGR exchanger (Exhaust Gas Recirculation Cooler or EGRC). In this field, it is known heat exchangers comprising a heat exchange bundle having a series of plates stacked parallel to one another above. The stack of plates is secured to a cover and inserted into a housing to which it is secured through the cover. The housing guides a fluid to cool through the bundle in which a cooling fluid circulates. The beam forms heat exchange surfaces, between which the fluid to be cooled and the cooling fluid circulate, in alternating layers, in fluid flow circuits. The plates are stacked together so that they are grouped in pairs of plates. Each pair of plates defines a portion of the coolant circuit, the fluid circuit to be cooled being defined between the adjacent plates belonging to two different pairs of plates. A problem encountered comes from the fact that the housing and the lid are subjected to mechanical stress when the heat exchanger operates.

The origin of these constraints comes on the one hand from the thermal expansion experienced by the housing when the fluid to be cooled passes through the beam at high temperatures. These thermal expansions of the housing will exert mechanical stress on the cover and cause deformation of the latter, which in turn will create a bending force on the beam.

On the other hand, the fluid to be cooled passes through the beam with a pressure that can vary enormously and in a very short period, which can cause significant variations in the mechanical stresses exerted in its passage circuit, that is to say between two plates adjacent two pairs of different plates. These mechanical stresses may then create a swelling of the beam, a deformation of the plates, the cover and / or the housing and a break in connections between the plates and / or between the plates and the cover. In some extreme operating conditions, one can go as far as expelling the lid. A first solution used is to solder the lid on the housing. Such a solution, however, requires the use of a metal case. In addition, the lid is no longer removable.

The invention aims to improve the situation. Thus, the invention relates to a bundle of heat exchanger plates, comprising a stack of plates intended to allow a heat exchange between a gas and cooling fluid flowing in contact with said plates at an exchange zone, said plates comprising securing means between them for guiding said gas and located at first and second ends opposite to each other, characterized in that the beam comprises at least one bar extending between the plates said one or more strips being located at the exchange zone, between the first and second ends, so as to connect a peripheral edge of the plates together. The invention thus makes it possible, thanks to the bar, to improve the mechanical strength of the beam and thus to reduce the amplitude of the deformation of the beam when the latter undergoes mechanical stresses. The bar or bars are arranged, for example, on the peripheral edge of the plates. They are arranged, in particular, parallel to the plate stack, that is to say transversely to the planes in which the plates extend and / or at an entire height of the beam. According to one aspect of the invention, the bar or bars are located at the middle of the peripheral edges.

According to an exemplary embodiment of the invention, the bundle comprises two bars, said first and second bars, the first strip being disposed on a first peripheral edge of the plates and the second strip being disposed on a second peripheral edge of the plates opposite the first . The first bar is arranged, for example, in the middle of the first peripheral edge of the plates and / or the second bar is disposed, in particular, in the middle of the second peripheral edge of the plates. According to an alternative embodiment, the bundle comprises a cover for holding the stack of plates, the said strip or bars being secured to the said lid. According to one aspect of the invention, said bar is attached to said beam. By the term "reported" is meant the fact that it is added to the beam, that is to say that it does not come from material of one of the components of the beam. The bar or bars are, for example, brazed to the beam. According to an exemplary embodiment, at least one see all the plates of the stack comprise at least one tab secured to another plate of the stack, the bar or bars being formed by the or tabs. The tongue or tabs are, for example, from the material of said plates of the stack. According to an alternative embodiment of the invention, the plates are arranged in pairs, each pair of plates comprising a first and a second plate arranged facing each other, the tongue or tabs of the first plate being secured to the one or more tabs of the second plate. The invention also relates to a plate for heat exchanger beam as described above.

The invention thus relates to a plate for a heat exchanger bundle, intended to allow a heat exchange between a gas and a cooling fluid circulating in contact with the plate at an exchange zone, said plate comprising securing means intended to be attached to another plate of the exchanger and to guide said gas, said securing means being located at a first and a second end opposite to each other, characterized in that said plate comprises at least one tab located between said first and second ends, along a peripheral edge of said plate, at the exchange zone, said tongue being arranged to be secured to another plate of the exchanger. The fastening of the tongue or tongues to another of the plates thus makes it possible to improve the mechanical strength of the beam and thus to reduce the amplitude of the deformation of the beam when the latter undergoes mechanical stresses. According to one aspect of the invention, the tongue is substantially in the middle of the peripheral edge.

According to an alternative embodiment of the invention, said tongue extends transversely to a plane defined by said plate. According to an exemplary embodiment of the invention, said tongue and said securing means extend in the same direction so as to be subject to the same other plate of the exchanger. Alternatively, said tongue and said securing means extend in an opposite direction. According to one aspect of the invention, a first of said tabs originates at a first peripheral edge connecting the first and second ends and a second of said tabs originates at a second peripheral edge connecting the first and the second. ends and opposite the first peripheral edge. The invention also relates to a heat exchanger comprising a beam 30 as described above, and / or at least one plate as described above.

The invention also relates to an air intake module for a motor vehicle engine comprising an exchanger as described above.

Other characteristics, details and advantages of the invention will emerge more clearly on reading the description given below as an indication in relation to drawings in which: FIG. 1 is an exploded perspective view of an exchanger according to the invention, and - Figure 2 is a perspective view of two plates according to the invention. Figure 1 illustrates a heat exchanger 1 fitted here an air intake module for a motor vehicle engine. Said air intake module has an outlet 9 of the intake air towards the cylinder head of the engine. Said outlet 9 of the module divides the flow of intake air, here in four separate streams.

Said exchanger 1 allows a heat exchange between a first fluid, for example a cooling fluid and a second fluid, in particular a fluid to be cooled. This exchanger is able to transfer the calories present in the fluid to be cooled to the cooling fluid. It is here an air / water exchanger, that is to say that the fluid to be cooled is, for example, a flow of engine feed gas and the cooling fluid is, in particular, added water of glycol. The exchanger 1 comprises a housing 2 having a body 3 which takes, for example, a generally hollow parallelepiped shape. The hollow part of this body 3 forms a housing 4 accessible through an orifice 5 delimited by a flange 6. The housing 2 is here obtained by molding. It is, for example, thermoplastic material, thermoset material or aluminum. The exchanger 1 also comprises a beam 7 intended to be installed in the housing 2, in particular in the housing 4. This beam 7 is inserted by translation through the orifice 5. The beam 7 here comprises a stack of plates 10 determining between them alternating circuits for the cooling fluid and for the gas, a pair of plates 10 of the beam 7 being illustrated in more detail in FIG. 2.

The stack of plates 10 is thus intended to allow a heat exchange between the cooling fluid and the gas flowing in contact with the plates 10, in particular at an exchange zone 51. Each plate 10 is in the same way intended to allow a heat exchange between the cooling fluid and the gas, especially at the exchange zone 51. The beam 7 is here of generally parallelepipedal shape and has an inlet face and an opposite exit face 17 gas. The body 3 has two lateral faces 11, 12, connected by a bottom 13 and two longitudinal faces 14, 15, said input 14 and 15 connecting the side faces. The longitudinal faces 14, 15 each comprise a frame defining an opening. The gas is thus intended to enter the exchanger 1 through the opening defined by the frame of the longitudinal inlet face 14 before passing through the beam 7 and out of the exchanger 1 through the opening defined by the frame of the longitudinal output face 15. The gas then leaves the intake module via its outlet 9 as seen above. A cover 25 of the bundle 7 is secured to the stack at an upper plate of the stack. The cover 25 is intended to be secured to the housing 2. It comprises a wall 26 arranged to close the orifice 5 through which the bundle 7 is introduced into the housing 2. The wall 26 is, in particular, substantially planar and here has a periphery 27, plane, configured to allow a removable attachment of the cover 25 on the housing 2. The periphery 27 comprises for this, in particular, fixing means to the housing 2, for example openings 21, in particular provided at the ears 20 It is thus possible to screw or rivet the cover 25 to the housing 2 and to separate it from the housing 2 without destroying the cover 25 and / or the housing 2. The beam 7 and the cover 25 are, in particular, made of aluminum or aluminum alloy. The wall 26 comprises a first face intended to be directed towards the inside of the casing 2 and a second face 29, opposite to the first and intended to be directed towards the outside of the casing 2. The exchanger 1 comprises tubings of inlet and / or outlet 18, 19, of the cooling fluid, communicating with orifices (not visible) provided in the cover 25 and allowing the cooling fluid to enter and / or exit the beam 7. FIG. a pair of plates 10 of the beam of the invention. The plates 10 include, for example, a first end 81 and a second end (referenced 82 in Figure 2) opposite the first end 81. They include, in particular, a first peripheral edge 83 and a second peripheral edge 84 opposite the first peripheral edge 83. The first peripheral edge 83 is located here on the side of the input face of the beam 7 and the second peripheral edge 84 is located here on the side of the exit face 17 of the beam 7. The first and the second ends 81, 82 are longitudinal ends of the plates. The plates 10 have, for example, the general shape of an elongated rectangle having two long sides and two short sides. The first and second ends 81, 82 correspond here to the small sides of the rectangle and the first and the second peripheral edges 83, 84 correspond to the long sides of the rectangle. The plates 10 are joined together, in particular at the first and the second ends 81, 82. Each plate 10 comprises for this purpose fastening means 90 arranged to join to another plate 10 of the beam to form a pair of plates 10. These securing means 90 take the form of wings, extending, in particular, transversely to a bottom 31 of the plates. The securing means 90 are located at the first and second ends 81, 82 of the plates 10. They are, in particular, intended to guide the gas in the beam, that is to say to guide it between two plates 10 of the same pair of plate. In other words, two plates 10 of the same pair of plates determine between them the circuit 22 for the gas. The bottom 31 of the plates 10 is substantially flat and surrounded by a peripheral edge 32 terminated by a flat portion 34, allowing the brazing of the plates together. The cooling fluid circuit 23 is defined, on the one hand, by the peripheral edge 32 and, on the other hand, by one or more edges 60, for example made of material from the bottom 31 of the plate. The circuits 23 for the circulation of the cooling fluid are here provided between two plates 10 vis-à-vis belonging to two pairs of adjacent plates. Two pairs of adjacent plates are joined to each other by their flats 34 and / or their edges 60. In this way, the circuits of two adjacent plates 10 belonging to two pairs of different plates 10 combine to constitute a circulation channel of the fluid of cooling.

The top plate of the plate stack 10 may be intended to be assembled with the cover 25 to define a coolant circulation channel.

Each plate comprises two stamped pockets 38, one of the pockets having an inlet 40 of the cooling fluid circulating circuit 23 and the other of the pockets having an outlet 42 of the circulation circuit 23 for circulating the cooling fluid.

The pockets 38 are here pierced with a passage 50 of the cooling fluid oriented perpendicular to the bottom 31 of the plates and are intended to come into contact with the pockets 38 of an adjacent plate 10 to form respectively an inlet manifold 43 and an outlet manifold 44 for the cooling fluid. The pockets 38 thus allow the cooling fluid to circulate between all the plates of the bundle. The inlet manifold 43 opens, for example, into the inlet pipe 18 through the inlet port of the cover 25 and / or the outlet manifold 44 opens, for example, into the outlet pipe 19 by the outlet port of the lid 25.

Thus, the cooling fluid enters the beam 7 through the inlet pipe 18 and is distributed between the plates 10 in the cooling fluid circulation circuits 23 by the inlet manifold 43. It flows into the circuits 23 of circulation of cooling fluid from their inputs 40 to their outputs 42 where it enters the outlet manifold 44. It then leaves the exchanger 1 through the outlet pipe 19. The pockets 38 are located along the same small side of the plates 10 located on the left in Figure 2, that is to say near the first longitudinal end 81 of the plates 10. The pockets 38 of a pair of plates 10 between them determine the height of circulation circuits 22 for the gas. The heat exchange zone 51 facilitating the exchange of heat between the cooling fluid and the gas extends between the pockets 38 and the second longitudinal end 82 of the plates. The zone where the pockets 38, that is to say the area near the first longitudinal end of the plates 10, is located, said zone stamped, is an area likely to allow the second fluid to bypass the exchange zone of heat. It may be obscured by a screen, not shown.

Each plate 10 comprises for example corrugations 52 arranged in the circuits 23 for circulating the cooling fluid. These corrugations 52 extend between the pockets 38 constituting the inlet manifold 43 and the outlet manifold 44 of the cooling fluid and the second end 82 of the plates 10. The corrugations 52 are, for example, derived from bottom material 31. plates 10, in particular by stamping the plates 10. The circulation circuit 23 for circulating the cooling fluid defined by the plates 10 makes it possible to guide the cooling fluid in a number n of successive passes, here two, in which the fluid circulates between the 40 and the output 42 of said circuit. Two adjacent passes are separated, for example, by the border 60 of the plates 10.

The passes are arranged parallel to each other in the direction of longitudinal extension of the plates 10. They may be provided in series one after the other.

The circulation of the gas in the gas circulation circuits 22 is effected in a direction generally perpendicular to that of the flow of the cooling fluid, that is to say from the inlet face of the beam 7 towards its exit face 17.

The exchanger may also include secondary exchange surfaces, for example corrugated disturbers reported between the plates 10 in the gas circulation circuits 22. These disruptors make it possible to disturb the flow of the gas so as to improve the heat exchange between the two fluids.

According to the invention, the beam 7 comprises at least one strip 100 extending between the plates 10, the strip or bars 10 being situated at the level of the exchange zone 51, between the first and second ends 81, 82, so as to connect the peripheral edge 83, 84 of the plates 10 between them. In the example illustrated in Figure 1, the bar 100 connects the second peripheral edges 84 of the plates 10 between them. The bar or strips 100 connect them, for example, at a middle portion of the beam 7, for example substantially in the middle of the first and / or second peripheral edge 83, 84. The beam 7 may comprise one or more bars 100 on the first peripheral edge 83 and / or one or more bars 100 on the second peripheral edge 84. According to one particular example of the invention, the bundle 7 comprises a bar 100 in the middle of the first peripheral edge 83 and a bar 100 at the middle of the second peripheral edge 84. The bar or bars 100 are here secured to the cover 25, in particular at the first face of the cover 25. It should be noted in FIG. 1 that the bar 100 is arranged, in particular, parallel to the stack of plates 10 and for example a whole height of the beam 7. It is thus arranged perpendicularly to the plates 10.

In this embodiment, the bar 100 is of substantially parallelepipedal shape. It comprises a face in contact with the peripheral edges of the plates. The strip 100 is here in contact with and secured to all the plates 10 of the stack. It is understood that the arrangement and the shape of the bar 100 5 can be modified, such as, for example, be arranged in "V". According to the embodiment illustrated in Figure 1, the bar 100 is related to the beam 7. The bar is then, for example, brazed to the beam.

According to a variant of the invention illustrated in FIG. 2, at least one plate 10 of the stack comprises at least one tongue 101 secured to another plate 10 of the stack. All the plates 10 of the stack comprise, for example one or more tabs 101. Here, the two plates 10 of the illustrated plate pair 10, said first and second plates 10, comprise a tongue 101. The tabs 101 are, for example, joined together. The bar 100 is in this case formed by the stacking of the tabs 101.

The tongue 101 is located between the first and second ends 81, 82 of the plate 10, along one of the peripheral edges of the plate 10 here the first peripheral edge 83 of the plate 10. It is at the level of the exchange zone 51, and is arranged to be secured to another plate 10 of the exchanger.

The tongue 101 is, for example, made from the material of the plates 10 of the stack. The plates 10 include, in particular, a tongue 101 at the first peripheral edge 83 and / or a tongue 101 at the second peripheral edge 84. The tongues 101 then take birth at the first and / or second peripheral edges 83, 84 plates. They are located, for example, in the middle of the first peripheral edge 83 and / or the second peripheral edge 84. The tongue 101 extends transversely to a plane defined by said plate 10, in particular transversely to the bottom 31 of the plate 10 It has a longitudinal extension much smaller than the longitudinal extension of the plate 10, in particular ten times smaller. Note here that the tongue 101 and the securing means 90 extend in the same direction so as to be subject to the same other plate 10 of the exchanger. In particular, the tongue 101 is substantially of the same dimension as the wings in their direction of extension transverse to the bottom 31 of the plates 10. The plates 10 of the same pair of plates 10 are thus joined together by their means of fastening 90 and their tabs 101. 20 25 30

Claims (9)

REVENDICATIONS1. A bundle (7) of heat exchanger plates (10), comprising a stack of plates (10) for enabling heat exchange between a gas and cooling fluid flowing in contact with said plates (10) at a an exchange zone, said plates (10) comprising securing means (90) between them for guiding said gas and located at a first and a second end (81, 82) opposite one another , characterized in that the beam (7) comprises at least one bar (100) extending between the plates (10), the said bar (s) (100) being situated at the level of the exchange zone (51), between the first and second ends (81, 82) to connect a peripheral edge (83, 84) of the plates (10) to one another. 2. Beam (7) according to claim 1, wherein the one or more strips (100) are located at the middle of the peripheral edges (83, 84). 3. Harness (7) according to claim 1 or 2, wherein the beam (7) comprises two bars (100), said first and second bars (100), the first bar (100) being disposed on a first peripheral edge ( 83) of the plates (10) and the second bar (100) being disposed on a second peripheral edge (84) of the plates (10) opposite to the first. 4. Beam (7) according to any one of the preceding claims, wherein the beam (7) comprises a cover (25) for holding the stack of plates (10), the said bar (s) (100) being secured said cover (25). 5. A harness (7) according to any one of the preceding claims, wherein said bar (100) is attached to said beam (7). 30 6. Beam (7) according to any one of claims 1 to 4, wherein at least one plate (10) of the stack comprises at least one tongue (101) secured to another plate (10) of the stack and wherein the at least one bar (100) is formed by the at least one tongue (101). A harness (7) according to claim 6, wherein the plates (10) are arranged in pairs, each pair of plates (10) comprising first and second plates (10) arranged opposite each other, the the tongues (101) of the first plate (10) being secured to the tongue or tabs (101) of the second plate (10). 8. heat exchanger (1) comprising a beam (7) according to any one of claims 1 to 7. 9. Air intake module for a motor vehicle engine, characterized in that it comprises an exchanger (1) according to claim 8.