| 摘要 |
<p>A safety device for motorized pedestrian access passage- ways, comprising a movement and supporting mechanism of an oscillating access shutter, which includes an electric motor (30) for activating the shutter, and a mechanical control system, which uses a series of levers (12, 13, 14, 14'), associated with respective elastic elements (22, 25), and a pushing element (31), suitable for allowing the automatic opening of the passageway, in the case of a lack of power supply, due, for example, to an electric black-out; in particular, the position in which the shutter almost completely closes the access passageway is an unstable equilibrium position, which is maintained thanks to the action of an electric motor (30), with an incorporated reducer, which contrasts the opening movement of the shutter, and the pushing element (31), which intervenes in the opening, when the shutter is positioned for completely closing the passageway.</p> |
