Automatic lid applying apparatus heretofore have been used to screw a threaded lid onto a threaded neck of a container to close the container after it has been filled. In a known lid applying apparatus, a lid is collected by a lid applying head that suspends the lid in a substantially horizontal plane. The lid is lowered onto the neck of the container to meet the lid and then the lid is rotated relative to the container thereby to screw the lid onto the neck.
A problem of cross-threading can arise if the lid is not placed on the neck so that the threads of the lid are in alignment with those of the neck. If the threads are cross-threaded, the subsequent forced application of the lid to the neck can result in the threads becoming damaged. This may lead to subsequent problems such a leakage.
U.S. Published Application No. 2004/0216430A proposes to solve the cross-threading problem by placing a lid (more specifically a cap) on the neck of a container and then rotating the lid relative to the neck in an opening direction. After such reverse rotation, the lid would be rotated in a closing direction. The rotation of the lid in the opening direction purportedly would correct any misalignment. That is, the threads presumably would settle into correct alignment prior to the application of the lid onto the neck of the container. This solution, however, requires the lid applying apparatus to be configured with a mechanism that can rotate the lid first in an opening direction and then in a closing direction, thereby increasing the complexity of the apparatus and the dwell time in the apparatus.
USPTO Backgrounds
USPTO Backgrounds