To reduce noise excepting during cleaning and save electricity consumption.

On cleaning operation, a number of revolution of pump 19 is raised to increase the flow amount of a solvent a valve 28 is opened to supply the solvent to a washing tank 10 through a bypath 27. While, during non- washing, the number of revolution of the pump 19 is slowed down to reduce the flow amount of the cleaning solvent and valve 28 is closed to flow the solvent to a chiller 25 and then return to a solvent tank 16. The refore, on washing a large amount of cleaning solvent is circulated, a high washing efficacy is obtained, and during the non-washing time, the solvent effectively purified by the filter 20 is assuredly cooled with a chiller 25.