Plug device for sealing liquid container

Abstract

A plug device for a liquid container is presented to enable cleaning of a flow passage of the liquid container as well as to eliminate the liquid being left in the flow passage during the operation of the liquid container, thus providing hygienic and safe operation of the container. The plug device consists of an outer plug member and an inner plug member which is detachably attached to the outer plug member. When the members are assembled, a flow passage is formed automatically to enable access to the liquid stored in the container. When a press button provided on the inner plug member is pressed down, the opening disposed at the bottom of a plunger device remains open, resulting in the interior space of the container being connected with the flow passage via the internal liquid passage. In this condition, the container can be tilted to dispense the liquid from the container. When the dispensation is completed, and the container is uprighted, the liquid in the flow passage is returned to the interior space of the container via a tapered surface formed on the inner plug member, thus leaving no liquid in the flow path. The plunger device is operated again to close off the opening, and thereby offering safe operation and enabling to maintain the quality of the liquid stored in the container, by removing a potential source of contamination from the residual liquid.