| 摘要 |
A closure having an inner closure part carrying an internal screw thread for screw threaded engagement with an external screw thread on the neck of a container. The closure includes an outer closure part at least partially enclosing the inner closure part. Co-operating retaining projections are provided on the inner and outer closure parts for retaining the inner closure part within the outer closure part, and permitting limited axial movement of the inner closure part within the outer closure part. First and second sets of castellations are provided on the inner and outer closure parts, respectively. The second set of castellations inter-engage the first set of castellations to permit a bidirectional torque to be transmitted from the outer closure part to the inner closure part when the outer closure part is rotated in a screwing-down direction. The set of castellations on one or both of the inner and outer closure parts are chamfered or rounded such that the height of the castellations decreases from the center of the castellations to the radially outer part of the castellations, whereby accidental engagement of the sets of castellations is substantially avoided when a bending moment is applied between the inner and outer closure parts. |
