An electrical tool assembly includes a battery-operated electrical tool, which has a housing and a charging terminal mounted in an insertion portion of the housing, and a charger, which has a receptacle fitting the contour of the insertion portion for the insertion of the insertion portion in a predetermined...http://www.google.de/patents/US7535197?utm_source=gb-gplus-sharePatent US7535197 - Rechargeable electrical tool and battery charger therefor
