| 摘要 |
The invention discloses a valve unit including a dispenser inlet ( 30,32 ) and a dispenser outlet ( 34 ). A metering chamber ( 40, 24 ) having a predetermined volume and two chamber openings ( 42, 42 ) is movably located inside the dispenser in a manner allowing at least one of the chamber openings to be moved between a first position where it is aligned with the dispenser inlet ( 32 ) and a second position where it is aligned with the dispenser outlet ( 43 ). Furthermore, a control member ( 26 ) is movably located inside the metering chamber between the chamber openings and is adapted to selectively close off the dispenser outlet. |
