Abstract: A screw capping head for use in a rotary capping machine includes a housing defining a longitudinal axis, a spindle rotatably carried by the housing, a first ring of magnets fixed within the housing, and a second ring of magnets coupled to the spindle for rotation with the spindle. The second ring of magnets is movable, without the use of tools, in the longitudinal direction with respect to both the spindle and the first ring of magnets to achieve a plurality of nested positions with respect to the first ring of magnets. The first and second rings of magnets define a magnetic torque coupling between the housing and the spindle, the strength of the torque coupling varying in a substantially linear relationship to the nested positions of the first and second rings of magnets.

Abstract: A screw capping head for use in a rotary capping machine includes a housing defining a longitudinal axis, a spindle rotatably carried by the housing, a first ring of magnets fixed within the housing, and a second ring of magnets coupled to the spindle for rotation with the spindle. The second ring of magnets is movable, without the use of tools, in the longitudinal direction with respect to both the spindle and the first ring of magnets to achieve a plurality of nested positions with respect to the first ring of magnets. The first and second rings of magnets define a magnetic torque coupling between the housing and the spindle, the strength of the torque coupling varying in a substantially linear relationship to the nested positions of the first and second rings of magnets.