Over-center self-adjusting equalizing cap chuck

A cap chuck comprising:

• a housing having an outer peripheral surface and an inner annular periphery, an external face adapted for operative attachment to a capping machine, and an internal face having a work piece receiving central area and an annular area bordering said inner annular periphery;
• a plurality of engagement jaws disposed along said annular area, each engagement jaw having a central portion, a first side portion, and a second side portion,
• said central portion having a cavity that accommodates a fastener therein to connect said engagement jaw to said housing and to establish a pivot point of said engagement jaw supporting limited axial rotational movement of said engagement jaw between a first axial position and a second axial position,
• said first side portion having
• a bias spring at a surface proximal of said inner annular periphery of said housing that pre-disposes said engagement jaw to said first axial position,
• an upper beveled area at least partially traversing an extension finger at a surface distal of said inner annular periphery of said housing, which, in use, serves as an actuator countering said bias spring when first contacted by a work piece;
• said second side portion having a surface proximal of said inner annular periphery which, in use, is initially disposed by said bias spring to abut said inner annular periphery but upon said upper beveled area being actuated by said work piece moves away from said inner annular periphery,
• said extension finger, in torque use, being capable of contacting an outer periphery of said work piece to apply gripping pressure in a direction toward a center-point of said work piece receiving central area of said internal face, and
• each of said engagement jaws being independent of each other and exerting separate points of pressure upon a work piece until said pressure thereon is equalized.