Heat exchanger and method for fabricating the same

Abstract

A heat exchanger comprises a base portion and a plurality of fins. The fins are disposed in parallel on the base portion. Each fin has an upper margin far away from the base portion. The distance between each upper margin and the base portion is substantially gradually reduced along a first direction. The upper margins sunken to form at least one groove. The groove extends along a second direction which intersects with the first direction. The structure of the heat exchanger can prevent cutting waste filling in the passages between fins and thus block of passages can be avoided.

What is claimed is: 
     
         1 . A method for fabricating a heat exchanger, comprising:
 providing a substrate, the substrate comprising a base portion and a processing portion on the base portion, a thickness of the processing portion being substantially gradually reduced along a first direction, at least one groove being formed on the processing portion, the at least one groove extending along a second direction which intersects with the first direction;   skiving a plurality of fins in parallel on the base portion, the plurality of fins extending along the first direction, the groove passing through each fin, each fin having an upper margin far away from the base portion, a distance between each upper margin and the bottom surface being substantially gradually reduced along the first direction; and   milling the plurality of fins along the first direction, the maximum distance between the upper margin and a bottom surface of the base portion being smaller than or equal to a preset value.   
     
     
         2 . The method according to  claim 1 , wherein the first direction is substantially perpendicular to the second direction. 
     
     
         3 . The method according to  claim 1 , wherein after the step of milling the plurality of fins along the first direction, the method further comprises:
 providing an upper casing, the upper casing having an accommodating space, a liquid input and a liquid output being connected to the accommodating space, and   assembling the upper casing to the base portion, setting the plurality of fins in the accommodating space, the liquid input and the liquid output being disposed at two opposite ends of the plurality of fins.   
     
     
         4 . The method according to  claim 3 , wherein the upper casing is assembled to the base portion by a solder. 
     
     
         5 . The method according to  claim 3 , wherein distance between the upper margin near the liquid input and the bottom surface is larger than distance between the upper margin near the liquid output and the bottom surface. 
     
     
         6 . The method according to  claim 5 , wherein the upper margin near the liquid input is substantially attached to the upper casing. 
     
     
         7 . The method according to  claim 1 , wherein the step of standing a plurality of fins in parallel on the base portion by milling and curving the processing portion further comprises:
 cutting the processing portion along a cutting direction which intersects with the upper surface an acute angle so as to form a fin; and   bending the fin to stand it on the base portion.   
     
     
         8 . The method according to  claim 1 , wherein upper margins of the plurality of fins form approximately a broken line. 
     
     
         9 . The method according to  claim 1 , wherein upper margins of the plurality of fins form approximately an oblique line. 
     
     
         10 . The method according to  claim 1 , wherein the substrate is fabricated by aluminum extrusion. 
     
     
         11 . A heat exchanger, comprising:
 a base portion having a bottom surface; and   a plurality of fins disposed on a side of the base portion far away from the bottom surface, each fin having an upper margin far away from the base portion, a distance between each upper margin and the bottom surface being substantially gradually reduced along a first direction, the upper margins sunken to form at least one groove, and the groove extending along a second direction which intersects with the first direction.   
     
     
         12 . The heat exchanger according to  claim 11 , wherein the first direction is substantially perpendicular to the second direction. 
     
     
         13 . The heat exchanger according to  claim 11 , further comprising an upper casing, the upper casing having an accommodating space, a liquid input a the liquid output being connected to the accommodating space, the upper casing being assembled to the base portion, the fins being set in the accommodating space, the liquid input and the liquid output being disposed at two opposite ends of the plurality of fins. 
     
     
         14 . The heat exchanger according to  claim 13 , wherein distance between the upper margin near the liquid input and the bottom surface is larger than distance between the upper margin near the liquid output and the bottom surface. 
     
     
         15 . The heat exchanger according to  claim 14 , wherein the upper margin near the liquid input is substantially attached to the upper casing. 
     
     
         16 . The heat exchanger according to  claim 11 , wherein upper margins of the plurality of fins form approximately a broken line. 
     
     
         17 . The heat exchanger according to  claim 11 , wherein the upper margins of the plurality of fins form approximately an oblique line.