One type of tamper-indicating closure includes a shell having a cylindrical skirt with one or more internal thread segments for threading the closure shell onto a container finish. A tamper band is frangibly connected to the edge of the skirt, and a stop flange extends radially inwardly and axially upwardly to engage an external bead on the container finish. When the closure initially is unthreaded from the container finish, the stop flange prevents axial movement of the tamper band, so that the tamper band is separated from the closure skirt to indicate that the package has been opened. Closures of this type are exemplified by U.S. Pat. Nos. 4,613,052, 5,197,620, 5,650,113, 6,053,344 and 6,224,802.
Tamper-indicating closures of the subject type can be made by compression molding or injection molding. In either type of molding process, the stop flange that extends from the tamper band is oriented axially outwardly of the closure as molded to facilitate molding and stripping of the closure from the mold. The stop flange must be inverted, from the axially outward orientation as molded to an axially inward orientation for use, prior to placement of the closure on a container finish. U.S. Pat. Nos. 4,653,657 and 4,721,218 illustrate a technique for stop flange inversion wherein a roller is engaged with the stop flange and the closer is rotated so that the stop flange progressively is inverted as a function of rotation of the closure. U.S. Pat. Nos. 5,090,788 and 5,443,171 illustrate another technique for stop flange inversion in which the edge of the stop flange is engaged by the shoulder of a plunger or mandrel to fold the stop flange bodily inwardly in a single operation. Although the techniques disclosed in the noted patents are generally successful in implementation, problems can be encountered particularly with closures having a fairly large diameter, in which the stop flange may not be inverted properly employing the noted techniques. A general object of the present disclosure is to provide an apparatus and method for inverting the stop flange on a tamper-indicating closure which address this problem in the art.
The present disclosure embodies a number of aspects that can be implemented separately from or in combination with each other.
An apparatus for inverting the stop flange on a tamper-indicating closure, from an axially outwardly oriented position as molded to an axially inwardly oriented position for use, in accordance with one aspect of the present disclosure, includes a support base for supporting the closure such that the stop flange as molded is spaced from and oriented away from the support base. A pedestal is movably carried by the support base at a position spaced from the support base. A locator ring is carried by the pedestal and movable with the pedestal to engage the stop flange on a closure carried by the support base and to bend the stop flange radially inwardly. An inversion ring moves through the locator ring to engage and invert the stop flange that is bent radially inwardly by the locator ring. The support base preferably is movable toward the locator ring and the inversion ring, such that the stop flange on the closure supported on the support base engages the locator ring and the inversion ring in sequence. The locator ring preferably has a surface that engages and rounds the closure prior to inversion of the stop flange.
An apparatus for inverting the stop flange on a tamper-indicating closure, in accordance with another aspect of the present disclosure, includes a support base for supporting the closure such that the stop flange as molded is spaced from and oriented away from the support base. A thread pilot is spaced from and opposed to the support base. A circumferentially continuous locator ring surrounds the thread pilot, and a circumferentially continuous inversion ring is disposed between the locator ring and the thread pilot. The support base is movable toward the thread pilot, the locator ring and the inversion ring first to engage the thread pilot and clamp the closure on the support base, then to engage the locator ring preliminarily to bend the stop flange radially inwardly, and then to engage the inversion ring further and finally to bend the stop flange to an axially inward orientation for use.
A method of inverting a stop flange on a tamper-indicating closure in accordance with a further aspect of the disclosure includes engaging the stop flange with a circumferentially continuous locator ring to bend the entire stop flange to a radially inward orientation, and then engaging the stop flange with a circumferentially continuous inversion ring further to bend the stop flange to an axially inward orientation for use.