Abstract: A package forming and sealing machine receiving articles confined within a conveyed tubular wrapper of sheet material, a rotor having sealing and cutting heads radially adjustable for changing the span between adjacent heads on the periphery of the rotor, there being a swingable jaw and a stationary jaw on each of the heads, a locking linkage to operate the swingable jaw, a rotary shaft to operate the linkage, and substantially continuously driven from a sprocket through a disengageable clutch operated by a trip arm and stationary stop cams also radially adjustable with respect to the rotor axis, a chain loop embracing revolving sprockets on the rotor to produce operation of the swingable sealing jaws.