PURPOSE: To provide a controlling device for flow rate of coating material constituted for preventing the variation of flow rate when the operation is changed over to a fluid of different viscosity.
CONSTITUTION: A coating material fed from a color change valve unit 1 is passed through a coating material tube 11 and fed to a coating material gun 16 through a flow rate control valve 2 and a vibtating mechanical flowmeter 3 and sprayed therefrom. At the time of color change, a preceding coating material remaining in the coating gun 16 is purged by thinner and air by means of changeover of the color change valve unit 1. The one round transfer gain of a flow rate control system is retained constant even if a control circuit 4 is changed over to the coating material or a thinner of different viscosity to prevent the flow rate variation caused by the sudden action of the flow rate control valve 2.
NISHIMURA MAKOTO
KIKUTA SATOSHI
SAWAMOTO KOJI
