Abstract: A two-sided fire door system includes a horizontal head track having a first end and a second end; a first door including a plurality of interconnected panels suspended vertically from the head track by trolleys arranged for horizontal movement between the first end and a point remote from the first end; a second door including a plurality of interconnected panels suspended vertically from the head track by trolleys arranged for horizontal movement between the second end and a point remote from the second end; and an endless chain in an elongate loop having a first end looped around a drive sprocket and parallel first and second runs fixed to respective first and second lead trolleys. A drive motor rotates the drive sprocket in opposite rotational directions to open and close the doors, the motor being blocked against rotation when the motor is not operating. A suspended weight closes the doors automatically by means of a cable attached to one of the lead trolleys when the blocking is released.

Abstract: There is provided an active brake release device attached to the exterior of a door controller having a first electromagnet, in which a sliding portion can slide to activate a sliding bar when the first electromagnet is energized; a first and a second actuator, in which the first actuator is located to abut against the break release bar of the door controller, and a sliding pin of the first actuator is yieldingly biased in the anti-activation direction of the bar; and, the second actuator is limited by a limit means at a fixed position; a second electromagnet, which is used to release the second actuator when the second electromagnet is energized; and a circuit, which includes a limit-switch for switching on the first electromagnet upon resetting of the device and a capacitor which is used to temporarily supply power to the second electromagnet in an event of unexpected electricity failure.

Abstract: A system and a latch mechanism adapted to release a curtain for deployment along one side of a window to protect the latter against burglary. This system comprises a curtain, a latch mechanism releasably holding the curtain and including an actuation bellows, a window having a vacuum space continguous to one face thereof, a fluid line from the vacuum space to the bellows, and a vacuum pump connected to the vacuum space, whereby a loss of vacuum in the latter will expand the bellows and then triggers the latch mechanism and thus releases the curtain which deloys itself under gravity to shield the window. The latch mechanism comprises a latch finger rotatable about its longitudinal axis and including a latch pin portion pivoted at one end about a transverse axis to freely drop to a downwardly hanging released position upon appropriate rotation of the latch finger.

Abstract: An insulating system for reducing heat loss from a structure during one part of the day and for permitting light to enter the structure during another part of the day, this system comprising a roll mounted on the structure, a flexible sheet of material wound around the roll, structure supporting the roll immediate its length and engaging portions of the wound sheet, and means for unwinding the sheet from around the roll and deploying it in a plane and for rotating the roll to rewind the sheet therearound; and a system for detecting build-up of snow or ice.