PURPOSE: To enable sealant to be evenly coated continuously to multiple screw thead parts by providing a coating part in continuation to the forward end of the turning part inserted with a spindle part and putting constituting elements such as drive part and coating part into a hermetically closed housing.

CONSTITUTION: When the work 1 stops in the specified position of the containing part I, the drive part A operates to advance a shaft 9, causing the truck part B to advance up to the wall surface 3 of the housing H. Thence, the spindle part E advances and when the coating part F goes into the screw thread part 1 of the work 1 through a through-hole 5, a turning brush body 44 detaches from a tapered part 31 and opens to make close contact with the screw thread part 2, thereby coating the sealant. Thence, the spindle part E is moved backward to reset the brush body 44 onto the tapered part 31 and further the spindle part E is retreated to impregnate and replenish the sealant to the brush body 44. When the work 1 having been coated falls downward, the next work 1 is stopped at the front face of the through- hole 5 of the containing part I to be ready for the next coating work.