US Patent 7427379 Liquid dispensing apparatus

A liquid dispensing apparatus comprises a liquid reservoir (32), an outlet port (6; 36) and driving means for forcing liquid (4) through the outlet port (6, 36). The driving means generates a pulse of gas which impinges upon the liquid (4) in the reservoir (32) so as to force liquid (4) through the outlet port (6, 36). Also disclosed is a cassette comprising a plurality of cartridges for dispensing liquid therefrom. Each cartridge comprises a liquid reservoir (32) and an outlet member (36) mounted so as to close an opening (34) in the liquid reservoir (32). The outlet member (36) provides an outlet port through which the liquid can be forced by a pulse of pressurised gas.