Capping method and capping apparatus

A capping method for a capping head for retaining a cap and a motor for rotating the capping head and in which the cap retained by the capping head is rotated in a cap-closing direction and rotationally fastens the cap to a container with a predetermined cap-closing torque, characterized in that the capping method comprises the steps of:

• fastening the cap temporarily to the container by rotationally fastening the cap to the container with a first predetermined torque;
• fastening the cap finally to the container by rotationally fastening the cap to the container with a second predetermined torque which is different from the first predetermined torque;
• setting a point of transition from the temporary fastening step to the final fastening step as a measurement starting point of a rotational angle;
• measuring the rotational angle of the capping head from the measurement starting point until the completion of the final fastening step;
• and
• determining whether the rotational fastening is acceptable according to whether the rotational angle is within a predetermined range,
• wherein the cap is rotationally fastened with a lower torque in the temporary fastening step than in the final fastening step and the measurement point is at a point in time at which the rotational speed of the capping head becomes lower than a temporary fastening completion speed.