Patent ID: 8307877
Filing Date: 2012-11-13
Classification: E05F,E05Y

Abstract:
1. A two-sided fire door system comprising: a horizontal head track having a first end and a second end; a first door comprising a plurality of first interconnected panels suspended vertically from the head track by a first group of trolleys following a first lead trolley remote from the first end, the first group of trolleys being arranged for horizontal movement between the first end and a point remote from the first end; a second door comprising a plurality of second interconnected panels suspended vertically from the head track by a second group of trolleys following a second lead trolley remote from the second end, the second group of trolleys being arranged for horizontal movement between the second end and a point remote from the second end; an endless chain in an elongate loop having a first end looped around a drive sprocket, a second end looped around at least one idler sprocket, a first run extending between the ends of the loop on one side of the head track, the first lead trolley being fixed to the first run, and a second run extending between the ends of the loop on the other side of the head track, the second lead trolley being fixed to the second run; a drive motor arranged to drive the drive sprocket in a first rotational direction wherein the lead trolleys move toward each other to close the doors, and a second rotational direction wherein the lead trolleys move away from each other to open the doors; a brake for blocking rotation of the drive sprocket when the drive motor is not operating; and means for urging the lead trolley in one of the first and second directions when the motor is not operating and the brake is released, whereby the door either opens or closes automatically.