| 摘要 |
A fire door has a hinged cover 2 pivotably mounted in a duct section 6 and at least one operating mechanism for pivoting the cover. This mechanism has an operating rod 20 engaging in articulated manner on the cover and whose end remote from the cover is connected by means of a joint 24 to the outer end of a connecting rod 26. The rotary movement of connecting rod 26 is limited to limit positions by stop members 30, 32 located a few angular degrees beyond the two dead centres of the crank movement. This leads to a locking of the hinged cover 2 either in the completely open position or in the completely closed position, which is only released after overcoming the dead centre again. <IMAGE> |
