Patent ID: 6953196

Claim:
An adapter for prompt engagement with a shank of a screw driver with a handle comprising: a hollow interior tubular adapter having a rear end enabling said adapter to connect to a handle, a polygonal central bore in a front end thereof which has a reduced bottom, a concaved front outer periphery to define a shoulder thereunder, a plurality of conical through holes spacedly formed around a middle peripheral wall of said concaved front outer periphery for respectively disposing a plurality of steel balls therein, a conical spring disposed into said polygonal central bore having a large thick upper portion positioned at inner side of said conical through holes for preventing said steel balls from entering into said central bore and a small incompact lower portion fixed into the reduced bottom of said central bore, an annular sleeve with an annular convex on a middle inner periphery slidably wrapped on outer periphery of said adapter wherein said annular convex is biased by a circular spring on said shoulder and said annular convex has a sloped upper surface engageable with said steel balls, an annular cap fixed a to top of said adapter with a circular ring engaged therebetween and a receiving space defined between lower end of said annular cap and the sloped upper surface of said annular convex for receiving said steel balls; a polygonal shank of a screw driver insertable into said polygonal central bore having an annular groove in a middle outer periphery engageable with said steel balls.