| 摘要 |
PURPOSE:To locally drain cooling water overflowing from a tank body without increasing the cost. CONSTITUTION:An overflow passage 3d is formed in a groove-like shape, in a cap 3 which blocks a filling port 1 of a tank body 2, being recessed outward of a cap body 3a from the inner surface of the latter. This overflow passage 3d is extended, radially of the cap 3, the cap body 3a to the outer peripheral wall 3b of the cap 3, being downward opened on the outside of the outer peripheral part 3b. Accordingly, when the cap 3 is fitted on the filling port 1, the overflow passage 3d on the cap body 3a side, is opened inward from the filling port 1, and the overflow passage 3d on the outer peripheral wall side is opened outside of the filling port 1. |
