| 摘要 |
<p>A collapsible helmet has curved sections of generally similar shape arranged in a fan-like manner and movable relative to one another in a circumferential direction with circular plates formed on the sections and stacked for relative pivotation of the sections. Inner and outer joint portions provided at opposite sides of the sections have first and second fasteners, the first restricting the circumferential displacement of the sections relative to one another, and the second restricting outward displacement of the adjacent sections when the helmet is erected. A cap overlying the circular plates biases them towards one another so as to releasably retain the sections in a spread condition and in a folded condition.</p> |
