| 摘要 |
A door controlling device for opening and closing a door in a wall having a linkage connecting between the door and a wall and an arm pivotable about a pin. A drive member on the pin has a stand by position which does not interfere with the manual movement of the door. Rotation of the drive member in one direction rotates the arm around the pin to move the door to the open position and rotation of the drive member in the opposite direction rotates the arm around the pin to move the door to the closed position. |
