Abstract: A capping machine includes a gripper having a pair of gripping arms provided on an outer peripheral portion of a rotating body and configured to grip a cylindrical portion of a vessel, an opening and closing device configured to open and close the gripping arms, and a capping head liftably and rotatably provided on the rotating body. The gripping arms are arranged symmetrically with respect to a radius of the rotating body. The gripper has a protrusion for preventing the vessel from rotating on a vessel gripping surface of the gripping arms. The gripping arms have outer and inner gripping surfaces which are connected in a V shape. The protrusion is formed only on the inner gripping surface of a right gripping arm. A cap held by the capping head is screwed onto the vessel while sticking the protrusion into the cylindrical portion.

Abstract: A chuck for a capping machine includes a plurality of chuck members, a biasing member configured to bias the plurality of chuck members radially inward, an abutting portion configured to abut against a top face of a cap, and a plurality of chuck jaws provided on an inner surface of each of the plurality of chuck members to engage knurls of the cap. Each of the plurality of chuck jaws includes a leading flank and a trailing flank. An angle of the trailing flank with respect to an outer circumference of the cap is less than an angle of the leading flank with respect to the outer circumference of the cap.

Abstract: A chuck for a capping machine includes a plurality of chuck members, a biasing member configured to bias the plurality of chuck members radially inward, an abutting portion configured to abut against a top face of a cap, and a plurality of chuck jaws provided on an inner surface of each of the plurality of chuck members to engage knurls of the cap. Each of the plurality of chuck jaws includes a leading flank and a trailing flank. An angle of the trailing flank with respect to an outer circumference of the cap is less than an angle of the leading flank with respect to the outer circumference of the cap.

Abstract: A capping machine includes a gripper having a pair of gripping arms provided on an outer peripheral portion of a rotating body and configured to grip a cylindrical portion of a vessel, an opening and closing device configured to open and close the gripping arms, and a capping head liftably and rotatably provided on the rotating body. The gripping arms are arranged symmetrically with respect to a radius of the rotating body. The gripper has a protrusion for preventing the vessel from rotating on a vessel gripping surface of the gripping arms. The gripping arms have outer and inner gripping surfaces which are connected in a V shape. The protrusion is formed only on the inner gripping surface of a right gripping arm. A cap held by the capping head is screwed onto the vessel while sticking the protrusion into the cylindrical portion.