| 摘要 |
The depth of thread in a roll-on closure is tested by determining the radial distance between the peak and valley defining a profile of the external surface of the threaded section. Apparatus for measuring the peak includes a first sensor broad enough to span the valley. Apparatus for measuring the valley includes a sensor able to fit into the valley. The container with the closure thereon is rotated to permit the latter sensor to enter to the full depth of the thread valley in case the point at which that sensor first encounters the surface of the closure is in a shallow end of the valley or not in the valley at all. If the second sensor moves far enough relative to the first sensor and in a radial direction with respect to the closure, the apparatus will respond to such relative movement as indicating that the closure has a predetermined thread depth. If the second sensor does not move far enough relative to the first sensor within a prescribed length of time or amount of rotation of a container, after the initiation of measurement of the closure on that container, the apparatus indicates that the thread depth of that closure is less than the predetermined value.
|
