Magnetic smoke and fire shield

A magnetic smoke and fire shield for controlling the flow of fluid through a conduit, comprising

• (a) a frame member adapted for mounting across said conduit, said frame member containing an opening;
• (b) a closure member connected with said frame member for movement between open and close positions relative to said frame opening, at least one of same frame and closure members being at least partially formed of a ferromagnetic material;
• (c) releasable retaining means including a fusible link and a hook member connected with said fusible link for maintaining said closure member in the open position relative to said frame member, said fusible link being meltable at a predetermined temperature to automatically move said closure member to the closed position, and said hook member being manually releasable from said fusible link to manually move said closure member to the closed position;
• (d) manual release actuating means including a length of fire and heat resistance material for manually releasing said hook member from said fusible link;
• and
• (e) magnetic sealing means mounted on the other of said frame and closure members operable upon release of said retaining means for maintaining said closure member in a closed sealed position relative to said frame opening.