Patent ID: 7285934

Claim:
A combination of a power supply and a detachable electric implement, a housing, said housing defining a receiving chamber, and including a body shell and a circular cover shell, wherein the body shell has an elliptical body portion and a circular head portion dimensioned correspondingly to and for mounting the circular cover shell so as to close the receiving chamber, and wherein the circular head portion has a greater sectional dimension than that of the elliptical body portion; a power pack mounted in said receiving chamber inside said housing, said power pack having power terminal means exposed outside said housing; an electric implement, said electric implement having power terminal means connectable to the power terminal means of said power pack to obtain the necessary working electric power from said power pack; and an open and replaceable coupling pair including a first coupling means implemented on said housing and a second coupling means implemented on said electric implement and detachably coupled to the first coupling means for fastening to said first coupling means to secure said electric implement to said housing and for keeping the power terminal means of said electric implement in contact with the power terminal means of said power pack.