Patent ID: 8528795

Claim:
A dosing device for dispensing metered doses of liquid from a container, the device having an outlet passage leading to a front discharge opening past or around a control chamber, which is positioned behind the front discharge opening and has one or more rear control openings to admit a restricted flow of liquid from the container interior into the control chamber, the device further comprising an obturator movable in the control chamber and adapted to advance, during dispensing, under the influence of liquid flowing into the control chamber behind it through said one or more rear control opening, to a blocking position where it blocks the outlet passage to terminate the dose, the device comprising a rearwardly-extending tubular formation defining part of the outlet passage in front of the obturator, said tubular formation having an annular periphery which presents a rearwardly-directed seat, and said device further comprising an annular elastomeric element around the rear edge of said tubular formation, the tubular formation surrounding the outlet passage and being engageable by a blocking portion at the front of the obturator in the blocking position, said annular elastomeric element providing a resiliently deformable sealing material at least around an annular engagement region of the rearwardly-directed seat which engages the obturator in the blocking position.