Metallic cooling fin for a heat exchanger, especially for a motor vehicle

Abstract

A metallic cooling fin for a motor vehicle heat exchanger has a central part having at least one set of fixed inclined lamellae, of selected form and spaced apart by apertures, the dimensions of which are predetermined to enable a fluid to pass between the lamellae. The lamellae in a common set are distributed in at least two groups, with the respective inclinations of the lamellae varying from one group to the other.

What is claimed is:  
     
         1 . A metallic cooling fin for a heat exchanger, having a central part formed with at least one set of inclined fixed lamellae of selected form, the said central part defining apertures of selected dimensions separating the said lamellae from each other whereby to enable a fluid to pass between the lamellae, wherein the lamellae of a said set are distributed in at least two groups each consisting of at least one lamella, each lamella defining an angle of inclination, the respective angles of inclination of the lamellae in the said set varying as between the said groups, each group having an order number, the order number increasing with the angle of inclination of the lamellae in the respective group.  
     
     
         2 . A fin according to  claim 1 , wherein two adjacent lamellae of different inclinations constitute part, respectively, of two said groups of lamellae having successive order numbers.  
     
     
         3 . A fin according to  claim 1 , defining a plurality of ranks of lamellae, the lamellae in the first and last ranks, in a said set of lamellae, being part of a first said group of lamellae having the lowest order number.  
     
     
         4 . A fin according to  claim 1 , having at least one said set of lamellae consisting of a plurality of groups of lamellae including a first group and a second group having a first inclination and a second inclination respectively, the said set of lamellae defining a median plane of symmetry.  
     
     
         5 . A fin according to  claim 3 , further including, upstream of the said lamella of the first rank, a fixed upstream auxiliary lamella having dimensions at least equal to those of the lamellae in the set, the upstream auxiliary lamella and the said lamella of the first rank defining an aperture of selected form between them.  
     
     
         6 . A fin according to  claim 3 , further including, downstream of the said lamella of the last rank, a fixed downstream auxiliary lamella having dimensions at least equal to those of the lamellae in the said set, the downstream auxiliary lamella and the said lamella of the last rank defining an aperture of selected form between them.  
     
     
         7 . A fin according to  claim 1 , having at least two successive said sets of lamellae comprising an upstream set and a downstream set, with the downstream auxiliary lamella of one said set and the upstream auxiliary lamella of an adjacent said set joining said one set and an adjacent set together.  
     
     
         8 . A fin according to  claim 5 , wherein the auxiliary lamellae define an inclination which is at most equal to that of the lamellae in the first group of the set.  
     
     
         9 . A fin according to  claim 8 , wherein the inclination of the auxiliary lamellae is less than that of the lamellae in the first group by an amount in the approximate range 1° and 20°.  
     
     
         10 . A fin according to  claim 7 , wherein the adjacent sets of lamellae have the same groups of lamellae.  
     
     
         11 . A fin according to  claim 10 , wherein the said groups having the same order number in two said sets of adjacent lamellae have opposite orientations.  
     
     
         12 . A fin according to  claim 7 , wherein the sets of adjacent lamellae have different groups of lamellae.  
     
     
         13 . A fin according to  claim 1 , wherein the lamellae define inclinations in the approximate range 15° to 35°.  
     
     
         14 . A fin according to  claim 3 , wherein the lamellae in the first said group define an inclination smaller, by a value in the approximate range 1° to 20° than that defined by the lamellae in the group having the highest order number.  
     
     
         15 . A fin according to  claim 1 , made of a material comprising aluminium.  
     
     
         16 . A fin according to  claim 1 , of copper.