Electric safety plugs and sockets

Claim 1

An electrical device for effecting connections between electric lines each having at least two conductors, said device comprising at least one male plug and one female socket mutually dimensioned to be coupled together; said plug and socket each comprising a body of insulating material through which the conductors extend; the body of the male plug comprising a sleeve with a hollow core having an internal wall; at least two contacts connected to the conductors extending into said plug and carried by said wall; the body of said female socket comprising an external tubular casing having an internal diameter substantially equal to the external diameter of the sleeve of the male plug to permit the introduction of said sleeve into said tubular casing; said body of the female socket further comprising a cylindrical mandrel disposed axially inside said casing and having a diameter substantially equal to the internal diameter of the sleeve of the male plug to fit in said sleeve; said wall of the sleeve of the male plug having slots; said contacts carried by the wall being retractively carried in the slots; elastic means in said slots and causing the contacts to project naturally from said wall into said hollow core; the mandrel of said female socket having on its surface at least two recesses; contacts respectively connected to the conductors and located within said recesses and completely within the outer surface of said mandrel whereby coupling of said plug and socket causes the male contacts to be biased into engagement with the female contacts located inside said recesses.