Heat exchanger with a mixing chamber

Abstract

A heat exchanger, in particular for a motor vehicle, comprises a collector box and at least one longitudinal row of multi-channel flat tubes through which a first fluid can flow. The collector box is made up of stacked plates including: a header plate with at least one row of mounting slots receiving an end portion of each tube, a distribution plate comprising at least one row of distribution slots, a cover plate comprising at least one row of collecting apertures which connect at least some of the distribution slots to a manifold, at least one collecting aperture being arranged between two adjacent distribution slots. Said collecting aperture is arranged in a main recess provided in the bottom face of the cover plate.

1 . Heat exchanger, in particular for a motor vehicle, comprising a collector box and at least one longitudinal row of multi-channel flat tube portions through which a first fluid such as a refrigerant fluid can flow and around which a second fluid such as air can flow, said tube portions being flat along a transverse direction and being connected to the bottom face of the collector box, wherein the collector box is made up of stacked plates including:
 a distribution plate comprising at least one row of distribution slots which distribute the first fluid in the collector box,   a cover plate comprising at least one row of collecting apertures which connect at least some of the distribution slots to a manifold, at least one collecting aperture being arranged between two adjacent distribution slots in order to connect jointly said two adjacent distribution slots to the manifold,   characterized in that said collecting aperture is arranged in a main recess provided in the bottom face of the cover plate in order to form with the upper face of the distribution plate a mixing chamber for the first fluid, said mixing chamber extending at least partially above said two adjacent distribution slots.   
     
     
         2 . Heat exchanger according to  claim 1 , characterized in that said collector box includes a header plate with at least one row of mounting slots receiving an end portion of each tube portion, said distribution plate being arranged between said header plate and said cover plate. 
     
     
         3 . Heat exchanger according to  claim 1  or  2 , characterized in that said collecting aperture is of oblong shape along an axis parallel to the distribution slots. 
     
     
         4 . Heat exchanger ( 10 ) according to any of the preceding claims, characterized in that said main recess ( 50 ) is of oblong shape along the manifold axis. 
     
     
         5 . Heat exchanger according to anyone of the preceding claims, characterized in that said manifold is made of one piece with said cover plate. 
     
     
         6 . Heat exchanger according to  claim 5 , characterized in that said main recess ( 50 ) is stamped in the bottom face of the cover plate such as to form a bump on the inner surface of the manifold which generates a section reduction in the manifold. 
     
     
         7 . Heat exchanger according to anyone of the preceding claims, characterized in that it comprises two rows of tubes and in that it comprises an inlet manifold and an outlet manifold. 
     
     
         8 . Heat exchanger according to anyone of the preceding claims, characterized in that the portion of the distribution plate which faces said collecting aperture is provided with an additional recess for enlarging said mixing chamber towards the distribution plate. 
     
     
         9 . Heat exchanger according to  claim 8 , characterized in that said additional recess is delimited transversally by two lateral surfaces which are facing each other, said lateral surfaces defining an increasing flow section towards each of the two adjacent distribution slots. 
     
     
         10 . Method for manufacturing a heat exchanger according to anyone of  claims 1  to  9 , comprising the steps of:
 extruding the cover plate, 
 forming the main recesses in the bottom face of the cover plate by stamping process, 
 piercing the collecting apertures in the main recesses.