Patent ID: 7422519
Filing Date: 2008-09-09
Classification: F23J

Abstract:
1. A chimney flue damper comprising: a first rigid peripheral frame surrounding an open window area corresponding generally to that of an end of the flue; a cap for covering said open window area in fixed alignment with said first frame; a rotatable second frame interposed between said cap and said first frame said rotatable second frame rotating with respect to said first frame and said cap upon opening and closing; said spring means biasing said cap in a direction away from said first frame to a window open position, said cap being movable toward said first frame against said spring bias to overlie and thereby close said open window areas; means pivotally interconnecting said cap and said second frame; and means preventing rotation of said cap relative to said first frame when the cap is moved toward and away from said first frame during respectively closing and opening said damper.