Patent ID: 7507297
Filing Date: 2009-03-24
Classification: B08B,Y10S

Abstract:
1. A cleaning method for removing adhering substances that adhere to at least a surface of a recess structure of a component that has the recess structure, the method comprising: accommodating the component to which the adhering substances adhere, in a cleaning bath; sequentially introducing a cleaning medium into the cleaning bath from a plurality of nozzles arranged radially on a cylindrical side surface of the cleaning bath so as to generate convection in the cleaning bath, the cleaning medium including carbon dioxide and water; changing a state of the cleaning medium alternately between a liquid state and a gaseous state by changing at least one of a temperature and a pressure of the cleaning medium so as to cause convection of a liquefied gas of the cleaning medium; and after said changing of the state of the cleaning medium alternately between the liquid state and the gaseous state, changing the cleaning medium in the gaseous state into a supercritical state to carry out the cleaning of the surface of the recess structure, wherein the component having the recess structure is a structure formed by a press molding or cutting method, wherein the adhering substances comprise organic matter including lubricating oil, and particle matter including swarf which has been pressed into the surface of the recess structure, and wherein the cleaning is carried out by utilizing a physical energy caused by a change in a surface tension of the cleaning medium accompanying a change in density and a change in viscosity of the cleaning medium, or a physical energy accompanying a change of state of the cleaning medium alternately between the liquid state and the gaseous state by the changing of the at least one of the temperature and the pressure.