Safety screw closure

US3944102A · kind A · utility

Inventor

• Hermann Grau · Mutlangen, DE

Key dates

• Filing date: Mar 30, 1973
• Grant date: Mar 16, 1976
• Expiry date: Mar 30, 1993

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B65D50/041
• WIPO field: Handling
• WIPO sector: Mechanical engineering

Abstract

A safety screw closure for use with a container having an inner screw cap on to the bottom edge of which an elastically expandable securing ring is attached by at least one rupturable bridge member. An outer cap is mounted on the inner cap and slidable axially between a first position remote from the inner cap and second position. A spring is located between the caps to normally urge the outer cap into the first position. The caps are provided with at least one set of cooperating coupling means which are in cooperation in any axial position of the outer cap when the closure is screwed on to the container whereas they are ineffective when rotating the outer cap in the opposite direction and when the outer cap is ints first position in which it is not depressed against the spring. The outer cap being dimensioned so that when in the first position it extends above the securing ring. The container has a threaded neck for receiving said inner cap and a shoulder having an inclinedslide surface adapted to expand the securing ring when said closure is threaded thereon.