Abstract: First divided booths 2 and 3 are moved to coating positions 2 to form a coating booth and an article to be coated carried by a carrying device is coated in the coating booth. Second divided booths 5 and 6 are retracted to cleaning positions C and cleaning booths 8 and 9 are moved from retracted positions T to operating positions S5 and S6 to cover the openings of the divided booths 5 and 6, and then cleaning is performed in this state. After the cleaning is completed, the cleaning booths 8 and 9 are returned to the retracted positions T, and the second divided booths 5 and 6 are moved to the coating positions P to form a second coating booth. After the coating by the first divided booths 2 and 3 is completed, the first divided booths 2 and 3 are retracted from the coating positions e to the cleaning positions C, the cleaning booths 8 and 9 are moved from the retracted positions T to the operating positions S2 and S3, and the cleaning is performed to ready for a next color change.

Abstract: In an electrostatic powder spray gun, a cylindrical air curtain is formed toward the front side of a gun main body by supplying compressed air to an air chamber formed between the outer peripheral surface of a cover member and an outer cylinder so as to eject the air from an air blowing opening. Owing to the air curtain, powder particles move toward an object to be coated without the risk of scattering to an ion trap electrode.

Abstract: A pair of measuring electrodes (63, 64; 73, 74) are provided along the circumferential portion of a cylindrical measuring tube (62; 72) made of an insulating material. The flow rate of powder passing through the measuring tube is measured as a change in the electrostatic capacity between the pair of measuring electrodes.