SCREW STOPPER FOR PLASTIC VESSELS Russian patent published in 2001 - IPC

FIELD: seals. SUBSTANCE: proposed screw stopper for plastic vessels has cap with side wall provided with thread on inner surface, bottom, safety tear-off ring connected with cap through weakened section, and seal. Screw stopper is provided with vertically installed threaded bushing and intake check valve. Cap is made in form of chuck enclosed from outside by ring clamp. Intake check valve is formed by cap bottom in which hole is made either aligned with hole of threaded bushing connected with cap or with disk located inside cap. Disk is connected with threaded bushing installed in hole made in cap bottom. Disk is provided with hole registered with hole in threaded bushing and with seal adjoining the cap bottom or disk. Seal is made in form of gasket made of elastic material and provided with at least one hole or one notch for subsequent cutting of hole. This hole is displaced relative to hole made in cap bottom or relative to hole made in disk. EFFECT: enlarged operating capabilities. 10 cl, 4 dwg