| 摘要 |
A control valve (5, 5') for connection units for flexible hoses is described, comprising a plurality of petals (segments or sectors) (6, 6'; 7, 7') rotatable between a position of complete opening and a position of complete closing. Said plurality of rotatable petals (6, 6'; 7, 7') consist of pairs of petals (6, 6'; 7, 7') with different shape and sizes, alternately arranged along the circumference of the connection unit. The petals (6, 6') of smaller size are controlled so as to close more slowly than those (7, 7') of larger size up to reach a contact position of the respective lateral edges. The upstream surface (57) of the petals (6, 6') of smaller size is provided with a pair of fins (59) laterally protruding from the above-mentioned surface so as to rest on the upstream surface (56) of the petals (7, 7') of larger size to oblige the latter to close before the petals (6, 6') of smaller size, whereas the upstream surface (56) of the petals (7, 7') of larger size is provided with a pair of projections (53) which, at the end of the closing movement of the petals (6, 6'; 7, 7'), are inserted in corresponding recesses (60) of the facing surface of the fins (49) for making a precise and stable coupling of the adjacent petals (6, 6'; 7, 7') in a tightly closed position. |
