PURPOSE: To perform uniform application, while making an application amount per unit surface constant, by detecting a relative velocity ratio between a nozzle and a workpiece to be coated, and ejecting an adhesive agent changeably in response to said value.

CONSTITUTION: A relative velocity ratio between a nozzle 1 and a workpiece W to be coated is detected by a mechanism 2 for detecting a velocity ratio. In response to said detected relative velocity ratio, an adhesive agent is changeably ejected by a variable ejection mechanism provided at an ejection mechanism 3. Hence, the application amount of the adhesive agent per unit length or area is made uniform, and the regular application of the adhesive agent is performed at all times.