| 摘要 |
A press-out piston is movably displaceable through an axially extending container holding a flowable plastic substance for dispensing the substance as the piston is forced through the container. The radially outer circumference of the piston has an annular groove in which an elastically deformable sealing ring is positioned. The base of the groove is conically shaped about the axis of the container and diverges outwardly toward the rear end of the container. When the piston is pressed toward the front end of the container for dispensing the substance, the sealing ring is moved axially relative to the piston and is pressed radially outwardly against the inside surface of the container. As a result, the seal for the piston is dependent on the pressure directed against the substance for dispensing it out of the container. |
