Cap having expandable guarantee strip

US5248050A · kind A · utility

Assignee

• Crown Cork · CH

Inventors

• Herwig Janousch · Bad Säckingen, DE
• Michael Kirchgessner · Egringen, DE
• Franz T. Bartl · Allschwil, CH

Key dates

• Filing date: Jun 24, 1992
• Grant date: Sep 28, 1993
• Expiry date: Jun 24, 2012

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B65D2401/35
• WIPO field: Handling
• WIPO sector: Mechanical engineering

Abstract

A tamper-evident screw cap for a bottle is disclosed. A guarantee strip on the cap possesses a predetermined breakage point at which the guarantee strip is able to be separated though its entire width. The predetermined breakage point most preferably comprises at least two ribs. Preferably, a window-shaped stress relief aperture is arranged near the predetermined breakage point to improve the expandability of the guarantee strip when the cap is being screwed on for the first time. In this instance, the stress relief aperture prevents the forces caused by the circumferential expansion of the guarantee strip from breaking the predetermined breakage point. When screwing the cap off for the first time, a flow of forces is created in the guarantee strip such that the stress relief openings are no longer effective and the guarantee strip fulfills its function by tearing or otherwise separating to indicate that the cap has been removed.