Method and apparatus for cooling of electrical devices

Electrical devices such as motors and generators create heat as they operate. This can lead to lower performance and life. Therefore, it is important to provide cooling for such devices. This is particularly true in heavy duty applications such as earthmoving or other industries. Methods and apparatus are disclosed to provide cooling that involves the circulation of two fluids in defined pathways. Heat within a case or other enclosure for an electrical device is transferred to one fluid. Heat from the one fluid is subsequently transferred to the other fluid. In one example, this heat transfer may occur across fins for increased effectiveness. It is also preferred that the flow of fluid beclosed loop so that contaminants are not introduced into the electrical device. By providing the heat transfer out of the electrical device as described, cooling is enhanced that can lead to longer lived and better performing devices.