| 摘要 |
<p>The present invention relates to a device making it possible, in the event of an accident, to open or to close a gate valve (1) the gate (3) of which moves in translation and is usually activated by a motor (6). The device according to the invention comprises a linkage system (7) including an enclosure (8) containing a ring (19) clamped tightly around the ends (20 and 21) of the operating shaft (4) and of the driveshaft (5). In normal operation a shear pin (22) secures the ring to the shafts (4, 5). In the event of the motor being unobtainable, under the action of the pressure of a fluid introduced via an orifice (30), the pin (22) breaks and the ring comes to bear on a stop (29) situated below the said ring and borne by the operating shaft (4) of the gate valve in order to act as a piston and close the gate (3) thereof. When the ring is not clamped directly around the ends of the two shafts, but the latter, penetrating one another, are clamped together in a connecting assembly supported by the said ring and when the operating shaft has a second stop situated above the ring, it is also possible to open the gate when the motor is unavailable. The device according to the invention makes it possible to retain use of the motor (6) under normal circumstances. <IMAGE></p> |
