| 摘要 |
<p>A cap-shaped cover for hollow-charge mines is adapted to form a hollow cavity adjacent to a portion of the mine. The cover, in its initial position, is in a folded, collapsed, introverted or the like closed condition and in its operational position, the cover is extended by a compression spring to assume a shell-like, hemispherical, or open configuration that defines the cavity. The cover includes at least one ventilating device for venting of the closed cover, a flexible body portion and the compression spring. The spring is formed of at least two separate, identical parts. These parts are arranged in the cover in such a way that the compression spring is symmetrical in all vertical section planes. The lead angle of a central turn section of each individual part of the compression spring, in the operational position of the compression spring, is 15 DEG -45 DEG , at least in the zone adjoining an outer turn section. Preferably, an inner turn section of the compression spring is held in a continuous groove of the covering member.</p> |
