Patent ID: 7229594

Claim:
A device for dispensing small quantities of at least one liquid, comprising: a reservoir ( 32 ; 61 ) that constitutes a supply of liquid (L) to be dispensed; a gas supply duct ( 10 ; 15 ; 32 ; 62 ) connectable to a gas supply (G), arranged to selectively supply a gas pressure; a capillary duct ( 20 ) having open first and second ends ( 20 a , 20 b ), the capillary duct being adapted to be filled with liquid (L) to be dispensed, and to eject said liquid; a wall that forms a bottom wall of the reservoir ( 32 ; 61 ), the capillary duct ( 20 ) extending through the thickness of said wall whereby the reservoir is integrated with the liquid-dispensing capillary duct; and a movable member ( 50 ; 15 , 20 , 42 ) movably mounted in the device above said bottom wall of the reservoir ( 32 ; 61 ) between a first position defining a filling configuration and a second position defining a liquid separation and ejection configuration, wherein: (a) in the filling configuration the movable member ( 50 ; 15 , 20 , 42 ) allows access of liquid in the reservoir to the top part of the wall into which the capillary duct ( 20 ) opens whereby liquid from the reservoir ( 32 ; 61 ) is in contact with an end ( 20 a ) of the capillary duct ( 20 ) to fill the capillary duct with liquid; and (b) in the liquid separation and ejection configuration: the movable member ( 50 ; 15 , 20 , 42 ) blocks access of liquid in the reservoir ( 32 ; 61 ) to a top part of the wall into which the capillary ( 20 ) duct opens, so liquid remaining in the reservoir ( 32 ; 61 ) is separated from liquid that fills the capillary_duct ( 20 ) to form a discrete quantity (V) of liquid filling the capillary duct out of contact with the remaining liquid (L) of the reservoir; the capillary_duct, filled with said discrete quantity (V) of liquid has its first end ( 20 a ) in contact with the gas supply and its second end ( 20 b ) directly or indirectly in contact with the, atmosphere; and said discrete quantity (V) of liquid is ejectable from the second end ( 20 b ) of the capillary duct by the application of gas pressure to the first end ( 20 a ) of the capillary duct when the gas supply duct is connected to said ˜as supply (G), the integrated reservoir ( 32 ; 61 ) being dimensioned to contain a quantity of liquid (L) that can be dispensed as multiple discrete quantities (V), a diameter or cross-dimension of the integrated reservoir ( 32 ; 61 ) being greater than the diameter of the capillary duct ( 20 ) which extends through the thickness of said wail; and the device being so arranged that the ejected quantities each correspond precisely to the discrete quantity (V) that fills the capillary duct ( 20 ) in the liquid separation and ejection configuration.