Oil cooler and production method

Abstract

The present invention uses a plurality of extruded tubes 8 to lead the oil from one oil cooler tank to the other oil cooler tank (one tank is the inlet tank of the oil cooler and the other one is the outlet tank of the oil cooler). In one application, the oil cooler tanks are identical. One tank functions as an inlet tank and the other tank functions as an outlet tank. Typically the ends of the tanks are threaded or equipped with some type of connector that allows the connection to the hydraulic lines leading the oil. The complete oil cooler is immersed in the cooling medium (the radiator coolant, typically a mixture of 50% water and 50% glycol). The heat of the oil is transferred through the tube walls to the cooling medium, so that the temperature of the oil leaving the oil cooler is significantly lower than the temperature of the oil flowing into the oil cooler.

What is claimed is:  
     
         1 . An oil cooler immersed in a cooling medium, the oil cooler comprising an oil inlet tank connected to an oil outlet tank by a plurality of substantially flat, pressure-resistant, seamless heat transfer tubes, the tubes connected to the tanks by brazing or other suitable process.  
     
     
         2 . The oil cooler of  claim 1  wherein the heat transfer tubes are aluminum extrusions with internal webs for pressure resistance.  
     
     
         3 . The oil cooler of  claim 1 , wherein multiple extruded tubes allow the oil to flow from the inlet port to the outlet port, thus the oil travel distance between the inlet and outlet ports is approximately the distance between said inlet and outlet tanks, while the heat exchange area is approximately equal to the heat exchange area of one tube multiplied by the number of tubes in the oil cooler.  
     
     
         4 . The oil cooler of  claim 1 , wherein the inlet and outlet tanks are approximately round, rectangular or any other suitable shape.  
     
     
         5 . The oil cooler of  claim 1 , wherein the extruded tubing is modified by dimples on one or both sides of the flat sides of tubing.  
     
     
         6 . The oil cooler of  claim 6 , wherein the dimples are round in shape.  
     
     
         7 . The oil cooler of  claim 6 , wherein the dimples are oval, rectangular or any other suitable shape.  
     
     
         8 . The oil cooler of  claim 6 , wherein the dimples are arranged in a linear fashion between the webs of said tubing.  
     
     
         9 . The oil cooler of  claim 6 , wherein the dimples are arranged in a zigzag fashion.  
     
     
         10 . The oil cooler of  claim 1 , wherein the extruded tubing is modified by convolutions formed by approximately 90 degree bends, or by convolutions of any other suitable angle or shape, in order to force the oil to repeatedly change its flow direction, thereby increasing turbulence and heat transfer.  
     
     
         11 . The oil cooler of  claim 1 , wherein turbulators are inserted in the passages of the extruded tubes to increase heat exchange, said turbulators consisting of bent wire, formed metal strips or any other bodies placed in the oilstream with the purpose of forcing the oil to repeatedly change direction and cause turbulence leading to an increase in heat transfer.  
     
     
         12 . The oil cooler of  claim 1 , wherein the cooling medium is the coolant contained in the inside of a radiator tank (water-cooled oil cooler).  
     
     
         13 . The oil cooler of  claim 1 , wherein the cooling medium is air (air-cooled oil cooler).  
     
     
         14 . The oil cooler of  claim 13 , wherein cooling fins are inserted between the tubes in order to increase the heat exchange area. In such a case the tubes may need to be banded together or otherwise held tightly together through brackets or other means in order to ensure tight contact between fins and tube surfaces, which is needed for efficient heat transfer.  
     
     
         15 . The oil cooler of  claim 1 , that can be used to cool automatic transmission fluid (transmission oil cooler).  
     
     
         16 . The oil cooler of  claim 1 , that can be used to cool engine oil (engine oil cooler).  
     
     
         17 . The oil cooler of  claim 1 , that can be used to cool steering oil, hydraulic fluid, and any other fluids requiring cooling in vehicles or other machinery.