| 摘要 |
PROBLEM TO BE SOLVED: To prevent a cap from being warped and to easily unload gas and liquid from the cap to the outside by equipping the cap with a top wall and a plurality of side walls being extended downward from the top wall, and providing an opening at the corner part between the two adjacent side walls. SOLUTION: At a corner part 18 between two adjacent side walls 14 of a cap 10, stress for creating the cap 10 is centered. Especially, when the cap 10 is to be manufactured by metal drawing, the stress is centered at the corner part 18 and distortion tends to be generated at the corner part 18. Since an opening 20 is provided at the corner part 18, the centering of the stress at the corner part 18 is relaxed when creating the cap 10, distortion cannot be generated and the cap 10 cannot be warped, thus obtaining the cap 10 in an accurate shape. Then, while the cap 10 is fixed to the substrate, gas and liquid can be unloaded from the cap 10 to the outside through the opening 20. |
