Electric power distributor for use in motor vehicle

摘要

An electric power distributor mountable on a motor vehicle for distributing power from a power source installed in the motor vehicle to a plurality of electric load units equipped in the vehicle has a plurality of semiconductor operative elements (14) which are incorporated in a power supply circuit from the power source to the electric load units; a control circuit board (18) incorporated with a control circuit for controlling an operation of the semiconductor operative elements; a housing (22) for encasing the semiconductor operative elements (14) and the control circuit board therein; and a heat releasing member (24) provided on an outer surface of the housing to release heat transferred from the semiconductor operative elements outside of the housing. The control circuit board is arranged at such a position as to be mounted over the semiconductor operative elements from a side of the housing opposite to the mounted side of the heat releasing member with respect to the semiconductor operative elements, and is formed with a heat transfer layer on a side of the control circuit board as opposed to the semiconductor operative elements. The heat transfer layer and the heat releasing member (24) are connected by a heat transfer member.