Patent Publication Number: US-10323886-B2

Title: Heat exchanger

Description:
The invention relates to a heat exchanger, in particular for a motor vehicle. 
     In this field, exchangers which are called charge air coolers are known, said exchangers permitting an exchange of heat between the charge air, designed to supply the engine of the vehicle, and a coolant. The exchangers comprise a heat exchange bundle consisting of a stack of plates, defining relative to one another alternate circulation channels for the charge air and for the coolant. It is important for such exchangers to be able to be arranged freely below the hood, in particular in the vicinity of the engine of the vehicle, in contrast to charge air exchangers which are cooled by a flow of external air and which have to be arranged on the front face of the vehicle or at least in the vicinity of an air inlet. 
     In such exchangers, the bundle is accommodated in a metal housing, collectors which enable the charge air to be guided at the inlet and outlet of the heat exchange bundle being attached thereto. 
     It has been proposed to attach the collectors to the housing by welding, said collectors being manufactured by casting. This solution, however, is not able to be easily mechanized. 
     It has also been proposed to braze collectors to the housing at the same time as the brazing of the remainder of the exchanger. In this case, the plates of the bundle have to be positioned in a stack accurately relative to the housing so as to permit a brazed connection which provides a good seal of the parts relative to one another. 
     To this end, it is possible to use positioning flanges for the plates attached to the housing but this makes the production of the exchanger relatively complex. 
     The object of the invention is to make improvements and to this end the invention proposes a heat exchanger, in particular for a motor vehicle, comprising a bundle for the exchange of heat between a first and a second fluid, and a housing, said bundle being accommodated in said housing, said exchanger further comprising at least one collector attached to said housing, said collector being configured to guide said first fluid between said bundle and an inlet or outlet of said exchanger, characterized in that said collector is configured to form an abutment for positioning the heat exchange bundle in the housing for assembling said collector to said housing. 
     Thus, according to the invention, a solution is proposed according to which the collectors permit said heat exchange bundle to be positioned in the housing without having to use added-on elements for positioning the bundle on the housing, which simplifies the structure of the assembly of the exchanger. 
     Advantageously, said collector comprises a wall which defines a chamber for the passage of the first fluid in the bundle, said wall being configured to form said abutment for positioning the heat exchange bundle in the housing for the assembly of said collector to said housing. 
     Thus the flow of fluid is prevented from being interrupted upstream and/or downstream of the bundle by the positioning abutments which could be located across the flow of fluid in the housing. 
     Advantageously, said bundle comprises plates for the circulation of the second fluid, said plates being stacked in a stacking direction in the housing, in particular vertically, and said abutment for positioning the heat exchange bundle in the housing being arranged therein so as to define a transverse position of the heat exchange bundle in the housing relative to the stacking direction of the plates, whilst permitting a freedom of movement in said stacking direction of the plates, when brazing the exchanger. 
     Advantageously, said positioning abutment consists of at least one deformation of said wall of the collector capable of retaining in position a part, in particular one or more corners of each of the plates, of the heat exchange bundle in the housing. 
     In particular, said abutment for positioning the heat exchange bundle in the housing comprises at least two said deformations of said wall of the collector, said deformations opposing one another relative to the plates of the heat exchange bundle. 
     Said deformation of the collector may be a fold in the wall of the collector, produced, for example, by stamping the wall of the collector and thus very simple to implement. 
     Said fold may be a lateral connecting edge of the collector to the housing, for example said edge forming with the housing a lateral cavity which is arranged so as to retain in position a part, in particular the corner(s), of each of the plates of the heat exchange bundle in the housing. 
     Advantageously, said lateral connecting edge of the collector is configured to cooperate with a lateral connecting edge of the housing to the collector, preferably along a planar connecting surface which promotes a brazed connection. 
     In particular, said edges of the collector and the housing are offset relative to one another so as to define a shoulder for positioning said bundle to form said lateral cavity which is arranged so as to retain a part in position, in particular the corner(s) of each of the plates of the heat exchange bundle in the housing. 
     More particularly, the depth of said edge of the collector is greater than that of said edge of the housing. The difference in depth of said edges constitutes, in particular, said shoulder for retaining in position the corner(s) of the plates of the bundle of the exchanger. 
     Advantageously, the plates of the heat exchange bundle are identical to one another, for example of rectangular shape, and the stacking thereof defines a parallelepiped, in particular a rectangle. 
     The heat exchanger may comprise said one collector forming the inlet collector of the exchanger and said further collector forming the outlet collector of the exchanger. Preferably, said collectors oppose one another relative to a central plane of the heat exchange bundle. In particular, said collectors together comprise four deformations of each of the collectors, each capable of retaining in position a corner of the heat exchange bundle in the housing. 
     The inlet collector and/or the outlet collector are configured so as to be connected, for example, to a conduit or hose for the circulation of the first fluid. 
     The exchanger may also form an air intake module in which the outlet collector is an air distributor which is configured to be attached to an engine cylinder head so as to distribute the air to the intake pipes of an engine cylinder head. 
     The invention may have the following complementary features, considered together or separately:
         said housing comprises a lower plate and/or an upper plate, at right angles to the stacking direction of the plates of the bundle, said lower and/or upper plates comprising an extension forming the wall of the collector,   the wall of the collector comprising said positioning abutment is a lateral wall connected to said upper and/or lower plates of the housing, in particular in the region of said extensions,   said bundle is attached to said collector by at least one of its corners.       

     Said exchanger is made, for example, of aluminum and/or aluminum alloy. It is possible to braze the collector to said housing in a single operation, said brazing advantageously being performed in a single operation or a single step when the heat exchanger is brazed, said exchanger having been previously assembled so that said bundle is positioned in said housing by said collector(s) using said positioning abutment. It could also be considered that the invention also relates to such a method for manufacturing a heat exchanger. 
    
    
     
       Further features and advantages of the invention will appear more clearly from reading the following description of embodiments of the invention provided by way of illustrative example, with reference to the accompanying drawings, in which: 
         FIG. 1  is a partial exploded perspective view illustrating an embodiment of a heat exchanger according to the invention, and 
         FIG. 2  is cross-sectional view along the line II-II of a part of the heat exchanger of  FIG. 1 . 
     
    
    
     Identical reference numerals are used to denote identical or similar elements. 
     As illustrated in  FIG. 1 , the invention relates to a heat exchanger  1 , in particular for a motor vehicle, comprising a bundle  3  for the exchange of heat between a first fluid A (along the arrow) and a second fluid L (along the arrow) and a housing  5 , said bundle  3  being accommodated therein. Said exchanger  1  further comprises at least one collector  7  attached to said housing  5 , for example an air inlet A collector  7  fixed to said housing as illustrated in the present case and an air outlet collector (not shown) which may be symmetrical to the inlet collector  7  relative to a central plane P of the bundle  3  or the heat exchanger. Said exchanger is produced, for example, in aluminum and/or aluminum alloy. 
     Said first fluid A may be charge air of the engine of the vehicle. Said second fluid L may be a coolant. 
     The housing  5  has in this case two parallel, substantially rectangular upper  11  and lower  13  faces, provided with a substantially trapezoidal extension  11   a ,  13   a . The extensions  11   a  and  13   a  of said upper and lower faces beyond the section or projection of the bundle  3  respectively constitute the upper and lower faces of the collector  7 . The housing further comprises two rectangular lateral walls  15 , opposing one another and connecting said upper  11  and lower  13  faces. It is noteworthy that as a variant (not shown) one wall thereof may constitute a collecting plate for the bundle connected to two respective inlet and outlet lateral collecting tanks for the second fluid. The housing thus comprises two faces which remain open, said faces opposing one another and called the first and second free faces  17 . 
     The inlet collector  7  for the first fluid is connected to the first free face  17  of the housing by an edge  17   a  of said housing, in this case said extensions  11   a  and  13   a  of said upper  11  and lower  13  faces are applied against a corresponding flat edge  18  of a cover  30  of the collector. The housing  5  is connected to the outlet collector (not shown) in the region of its second free face. Thus the first fluid A passes through the heat exchange bundle  3  guided by the housing  5 , on both sides from the inlet collector  7  to the outlet collector, entering and leaving the exchanger via connecting tubes  19  to conduits or hoses for the circulation of fluid, by means of respective inlet and outlet orifices  21 . 
     Each of the upper and lower faces  11 ,  13 , and lateral wall  15  of the housing consists in this case of a plate, said plates being attached to one another by their edge, in particular by brazing, to form said housing. 
     Circuits for the circulation of the first fluid A are provided in the heat exchange bundle  3  via agitators  32 , only the agitators of an upper and lower part of the bundle having been shown. More specifically, in the example, the bundle  3  is formed of parallel plates  23  stacked in a stacking direction D, said plates permitting the circulation of the first and the second fluids A, L so as to ensure an exchange of heat between said fluids. 
     The plates  23  are grouped into pairs and together define a circuit for the circulation of the second fluid L. An upper plate and a lower plate of one and the same pair of plates  23  complement one another to form a conduit for the circulation of the second fluid L. The plates  23  of one and the same pair comprise two opposing projections (not shown) permitting the second fluid L to pass into the conduit formed by said pair of plates, said projections of one pair of plates being connected to the projections of the pairs of adjacent plates. Said housing comprises an inlet conduit  25  and an outlet conduit  27  for the second fluid L, located on one side of the housing, said conduit inlet  25  and outlet conduit  27  conduits discharging opposite cavities for the circulation of the second fluid L formed by said projections. The circuits for the circulation of the first fluid A are defined by the plates  23  of two pairs of adjacent plates. 
     The plates  23  here have the general shape of an elongated rectangle having a length slightly less than that of the upper and lower faces  11 ,  13  of the housing and having a width equal to that of the lateral walls  15  of the housing (see also  FIG. 2 ). The stacking of the plates  23  forms a rectangular parallelepiped. 
     Said bundle  3  is attached to the assembly consisting of the housing  5  and collectors  7 , in particular, by brazing. More specifically, each of the covers  30  of the collectors  7  comprises a lateral wall  29  connected to the lateral walls  15  of the housing along a lateral edge  29   a  of the wall  29  of the collector joining an edge  15   a  of the wall  15  of the housing. 
     As will appear more clearly from  FIG. 2 , said edges of the collector and housing  29   a ,  15   a  form a shoulder or a lateral cavity  31  shaped as a right angle or corner, the apex thereof being defined by a line parallel to the stacking direction of the plates  23 . In this manner, an abutment  9  is defined, said abutment being capable of retaining in position in the housing, with a small amount of clearance, one or more corners  23   a  of each of the stacked plates  23  of the heat exchange bundle. 
     The depth I of said edge  29   a  of the collector is greater than the depth I′ of said edge  15   a  of the housing. The difference in depth I, I′ of said edges  29   a ,  15   a  constitutes said shoulder or cavity  31  for retaining in position the corner(s)  23   a  of each of the stacked plates  23 . Said edges  29   a ,  15   a  are produced here by stamping the walls  29 ,  15  of the collector and the housing, which as already mentioned are made of metal, for example, in particular aluminum and/or aluminum alloy. 
     Said lateral edge  29   a  of the wall of the collector cooperates with the lateral edge  15   a  of the housing due to a connection produced along a flat connecting surface, surface to surface. In total four shoulders or cavities  31  are formed, two per collector, to receive the four corners of each of the plates and by extension the four edges of the rectangular parallelepiped consisting of the stack of plates. 
     As mentioned above, each of the collectors  7  may be brazed to said housing  5 , at the same time as the brazing of the housing  5  and the bundle  3 , in particular the different stacked plates  23  which constitute said bundle. Thus, it is possible to braze said housing  5 , bundle  3  and collectors simultaneously in one operation. 
     Generally, according to the invention, the collector  7  is configured so as to form an abutment  9  for positioning the heat exchange bundle  3  on the housing  5 , for assembling said collector to said housing. By this is understood that the assembly of the collector on the housing positions the bundle in said housing. In the case of a manufacture of the exchanger by brazing, such a positioning takes place before brazing the parts together. This has the purpose of ensuring the quality of the brazing whilst providing the prior positioning of the parts. In particular, such an assembly takes place before the exchanger is moved into a brazing furnace. 
     Such an assembly before brazing may be obtained by crimping the walls  29 ,  15  of the collector and the housing, in this case using the teeth  34  of the housing cooperating with the clips  36  of the collector ( FIG. 1 ). 
     It is noteworthy that, due to the cavities or shoulders  31 , the plates  23  are positioned in a stack accurately relative to the housing (transversely to the vertical stacking direction of the plates, in vertical alignment) so as to be maintained horizontally in the housing whilst permitting a freedom of movement in the vertical direction for connecting the plates to one another by brazing. 
     It is also noteworthy that the abutment formed by the invention does not occupy, or only occupies to a small extent, the surface for the passage of the first fluid through the bundle. In this manner, an interruption to the flow of said first fluid and the reduction of the heat exchange surfaces are prevented. 
     Moreover, this design of the collector formed with wall extensions of the housing and a single cover  30  facilitates the punching of said cover  30  whilst permitting, in a single forming operation, to obtain simultaneously said deformations for positioning the bundle in the housing and the connecting edges for brazing to the housing. 
     According to a variant, not illustrated, the heat exchanger may also form an air intake module in which the outlet collector is an air distributor which is configured so as to be attached to an engine cylinder head in order to distribute the air to the inlet pipes of the cylinder head. The first fluid then circulates through the inlet collector, the exchanger and the air distributor. 
     The various features, described above, of the different elements of the exchanger may be combined together or provided separately from one another, if appropriate.