Fire damper assembly for sealed penetrations

Claim 1

A plural fire damper assembly adapted for sealed mounting in a penetration through a fire resistant wall, the assembly blocking passage of fire through said penetration and including vibration protection, said plural fire damper assembly comprising: A. a plurality of fire dampers, each having a four sided, rectangular, sheet metal frame that is open front and back to define a circumferentially surrounded passageway for normal passage of air therethrough, there being a plurality of blades within the frame arranged to close the passageway to passage of air and fire therethrough upon melting of a link under heat of fire, each damper having a height and width and requiring expansion spaces along its height and width to accommodate thermal expansion of its components and insure complete closing of the passageway by the blades in the heat of a fire; B. a first outer frame for each fire damper, each first outer frame having four sheet metal sides formed in a rectangular arrangement that is open front and back to define a circumferentially surrounded passageway therethrough, each said first outer frame having a height accommodating the height and required height expansion space of its respective fire damper and having a width accommodating the width and required width expansion space of its respective fire damper, each fire damper being installed in the passageway of its respective first outer frame with the four sides of the fire damper being juxtaposed the four sides of the first outer frame and the passageways therethrough being aligned with one another; C. first retainer means secured to each of said first outer frames for retaining each fire damper within its respective first outer frame while blocking the passage of air and fire through the expansion spaces between the fire damper and first outer frame and accommodating expansion of each fire damper into said expansion spaces under heat of a fire; D. first resilient spacer means located in said height and width expansion spaces between each said fire damper and first outer frame for limiting movement of said fire damper in said outer frame otherwise induced by vibration while accommodating thermal expansion of said fire damper into said expansion spaces; E. said first outer frames being joined together to form a joined structure having said fire dampers in side by side rectangular arrangement, said joined structure having a height and a width and requiring expansion spaces along its height and width to accommodate thermal expansion of its components and insure complete closing of each fire damper passageway by the blades in the heat of a fire; F. a second outer frame having sheet metal sides formed in a rectangular arrangement that is open front and back to define a circumferentially surrounded passageway therethrough, said second outer frame being adapted to be sealed in the penetration and having a height accommodating the height and required height expansion space of said joined structure and having a width accommodating the width and required width expansion space of said joined structure, the joined structure being installed in the passageway of the second outer frame with the sides of the joined structure juxtaposed the sides of the second outer frame and the passageways therethrougn being aligned with one another, G. second retainer means secured to said second outer frame for retaining said joined structure within the second outer frame while blocking the passage of air and fire through the expansion spaces between the joined structure and the second outer frame and accommodating expansion of the joined structure into said expansion spaces under heat of fire; and H. second resilient spacer means located in said height and width expansion spaces between said joined structure and said second outer frame for limiting movement of said joined structure in said second outer frame otherwise induced by vibration while accommodating thermal expansion of said joined structure into said expansion spaces.