| 摘要 |
<p>PURPOSE:To obtain excellent strength in the facing direction of the long sides and diagonal direction of the corners of a container having almost a square cross section without an increase in the number of ribs by a method wherein the rib having a trough-shaped cross section is provided around the body of the container and the bottom of the rib is formed in an arc-shape so that the bottom of the rib becomes deepest in the middle of each long side. CONSTITUTION:A container 1 has a cross section of an inequilateral octagon that is created from a square by cutting off its four corners at an angle of 45 deg.. A rib 3 having a trough-shaped cross section is provided around the middle of a body 2 of the container 1, and the bottom 20 of the rib 3 is formed in an arc-shape that is curved inward so that the bottom 20 is shallow at both ends 11 of each long side 10 and gradually deeper toward the middle 12 of the long side 10. Therefore, the cross section of the rib 3 continuously changes, forming a bridge. As a result, there is not a risk of losing its strength sharply with a remarkable change in the shape of the rib 3, so that an excellent strength can be obtained not only in the facing direction of the long sides 10 of the container 1 but also in the diagonal direction of th corners 16 of the container 1.</p> |
