| 摘要 |
<p>A liquid delivery device (10) for delivering a nutritive liquid (13) to a subject comprises a reservoir (12) for the nutritive liquid connected, in use, to a gas generator (11) for supplying a gas to the reservoir (12) to drive the liquid (13) therefrom. The generator (11) comprises first and second compartments (16, 17), each containing a reactant (19, 20), the compartments (16, 17) being interconnected in a manner which permits the flow, in use, of a reactant (19) from the first compartment (16) to contact the other reactant (20), the reactants in the form of citric acid solution (19) and powdered sodium bicarbonate (20) reacting on contact to generate a gas, wherein an increase in gas pressure within the generator (11) reduces the rate of flow reactant (19) from the first compartment (16), thereby controlling the rate of gas generation by feedback and in turn the rate of liquid delivery. Delivery of liquid from the device (10) can be stopped by clamping a tube (14) leading from the reservoir (12), and the resultant increase in pressure in the reservoir (12) and in the gas generator (11) cuts off the flow of reactant (19) from the first compartment (16) and thereby stops the reaction. Only when the tube (14) is unclamped and there is a resultant decrease in pressure within the reservoir (12) does the flow of reactant recommence. Thus, delivery can be interrupted for periods of 20-30 hours and subsequently recommenced with full effectiveness.</p> |
