Abstract: A capping head including a housing assembly including a magnetic clutch interconnecting a drive spindle and a quill for applying a closure to a container. The magnetic clutch consists of opposed rings of magnets and one of the rings is disposed in a piston ring assembly that is quickly and easily adjustable relative to the other to vary the torque limit of the clutch. A simple yet efficient clamping assembly is employed to facilitate ready adjustment and retention of the movable piston ring.

Abstract: A method of forming either a metal or plastic pilferproof closure is disclosed. The closure has an end wall and an annular sidewall depending therefrom. For a metal closure, an annular ring is rolled in the sidewall so that it protrudes outwardly therefrom. The sidewall is scored adjacent to the annular ring to form a plurality of fracturable bridges which divide the sidewall into upper and lower portions. The annular ring is then compressed so as to form an annular bead which at least partially covers the bridges. The upper portion is susceptible to being deformed about the threaded neck of a container while the lower portion is adapted to be at least partially turned inward and into engagement with an annular shoulder formed on the container below its threaded neck. The annular bead serves to protect the fingers of a person who is removing the closure from coming in contact with the sharp edges of the broken bridges.