Solution feeding apparatus and solution feeding method

摘要

The invention is directed to a solution feeding apparatus and a solution feeding method that are capable of feeding solution from a container until the container is completely empty while maintaining a precise feeding rate to the end of the feeding process. The solution feeding apparatus may include a solution-feeding pump connected via a tube to a container which hermetically contains a solution and is capable of changing its shape in accordance with the amount of its content is provided with a gas-liquid separation tank and a gas detection sensor. The gas-liquid separation tank serves to separate gas from solution and may be disposed in the portion of the apparatus between the container and the pump. The gas detection sensor may be disposed in the gas-liquid separation tank and serves to detect gas that has entered the solution channel. An air pump is operated in sync with the gas detection sensor so as to discharge gas out of the gas-liquid separation tank, thereby constantly maintaining gas in the solution channel at a given quantity. The apparatus is also provide with a solutions depletion sensor adapted to detect reduction of the pressure in the solution channel, which pressure reduction results from depletion of the solution in the container.