Abstract: A lead portion 18 and a cap mounting portion 34 are provided at a lead end portion of a main shaft 10 of a liquid applicator. A projected portion 36 is formed on an outer circumferential surface of the cap mounting portion 34, A cap mountable to this main shaft is formed with lines of projection 30, 32 on inner circumferential surfaces of bottom and intermediate end portions thereof respectively. The projection 30 is movable over the projected portion 36, whereas the projection 32 is engageable with an outer circumferential surface 19 of the lead portion 18. The respective portions are positioned relative to one another such that the projection 32 is engageable with the outer circumferential surface 19 after the projection 30 moves over the projected portion 36. Accordingly, there can be prevented a loss of airtightness in the cap due to an incomplete cap mounting operation without impairing the facility to mount the cap to the main shaft.

Abstract: First, second, and third bottom stepped portions 18, 20, 22 are formed stepwise at a lead end portion of a casing 10 of a liquid applicator. First, second, third, and fourth lead stepped portions 32, 34, 36, 38 are formed stepwise at a bottom end portion of a lead portion 12 of the liquid applicator. Lead end faces 24, 26 of the second and third bottom stepped portions 20, 22 are adhered with bottom end faces 40, 42 of the second and third lead stepped portions 34, 36 by means of an ultrasonic adhesion in a state where the respective bottom stepped portions are brought into contact with the corresponding lead stepped portions. Accordingly, the adhered faces are prevented from coming apart at each adhered portion in the liquid applicator including lead and bottom side shafts which are coupled with each other by means of ultrasonic adhesion.