1. Field of the Invention
This invention relates to closures for dispensing contents from a container and, more particularly, to such closures having a lid which plugs the dispensing opening when not in use and which is biased open to prevent interference with dispensing of product during use.
2. Background Information
A common type of closure for dispensing liquid, granular or viscous product from a container includes a base which screws onto the container neck and has a dispensing opening smaller than the container opening in an end wall. In order to plug the dispensing opening between uses, a stopper is provided on a lid which is hinged to pivot between a closed position with the stopper plugging the dispenser opening and an open position with the stopper removed. The lid may be a separate piece pivotally mounted on the base by a hinge. More often, the lid is connected to a support piece by an integral hinge with the support piece secured to the base. The entire closure can be molded as a single piece with the support piece tied to the base by another integral hinge or hinges, or the support piece and lid can be molded separately from the base. In either case, the support piece is fixed in place on the base by a snap connection. Typically, the snap connection is made by a pin with an enlarged head which projects through and is captured in an opening through the end wall, by nipples (sometimes hollow) which engage a recess, or by friction fit of a projection into a slot.
As the container is tilted or even inverted in order to dispense the product, various arrangements are provided to prevent interference of the pivoted lid with product flow. In some such closures, a portion of a skirt on the lid is engaged to hold the lid open. In other such closures, tabs extending in the plane of the lid bear against the end wall of the base or engage recesses in the base as the lid rotates over center.
In designing such closures, consideration must be given to ease of manufacture assembly and use, reliability and, of course, cost. There is room for improvement in all of these areas.