Cooling arrangement for a power inverter

Abstract

A power inverter has a housing enclosing inverter electronics including power transistors electrically coupled to a DC voltage input for supplying an AC voltage output. The inverter electronics are mounted on a circuit board that is fastened to the housing and the housing has a housing wall with air vents. A heat sink including cooling fins forming air channels is mounted on the circuit board and the power transistors have a heat transfer relationship with the heat sink. A fan is mounted in a further housing wall. The heat sink is disposed so that an air stream is created through the air channels of the heat sink and between the air vents and the fan for dissipating heat generated by the power transistors.

What is claimed is:  
     
         1 . In a power inverter having a housing enclosing inverter electronics including power transistors electrically coupled to a DC voltage input for supplying an AC voltage output, wherein the inverter electronics are mounted on a circuit board that is fastened to the housing and the housing has a housing wall with air vents for admitting air into the housing, the improvement comprising: 
 a heat sink including cooling fins forming air channels, the heat sink being mounted on the circuit board and the power transistors being fastened to the heat sink; and    a fan mounted in a further housing wall opposite the housing wall with the air vents and being operative for blowing air out of the housing;    wherein the heat sink is disposed between the air vents and the cooling fan so that a cross flowing air stream is created from the air vents through the air channels of the heat sink and out of the housing through the fan for dissipating heat generated by the power transistors.