PURPOSE: To prevent a pipe line between a parent pump and a quantitative coating pump from being damaged due to excessive pressure so as to reduce the running cost of a quantitative coating device, by forming an opening in the body of a cylindrical coating pump, and by arranging a variable internal volume type closed container connected thereto with a bellows type peripheral wall so as to surround the opening.

CONSTITUTION: Coating liquid fed from a supply tank 13 to a parent pump 14 is fed into the body 1 of a cylindrical quantitative coating device through a supply port 3 so that the coating liquid flowing through an opening 2 is pooled in a closed container 6 while it extends a lower stage bellows side peripheral wall 6a upward. When the quantity of the coating liquid becomes nearly full, a full quantity sensor 10 delivers a detection signal so that the parent pump 14 stops its operation. With the repetition of such operation the coating liquid pooled in the closed container 6 is fed stably always into a quantitative coating pump 4 at the lower end of the device body 1. The pressure in a pipe line between the parent pump 14 and the pump 4 is prevented from being excessive, due to intermittent operation of the parent pump 14 and variations in the volume of the closed container 6, and therefore, it is possible to prevent the pipe line from being damaged. Further, useless operation of the parent pump may be reduced thereby it is possible to reduce the running cost of the quantitative coating device.