Self-closing fire door

A door comprising:

• a curtain including a plurality of interconnected relatively pivotal slats aligned in a single direction;
• a guide positioned on one side of said curtain for guiding said curtain for movement between a first or opened position and a second or closed position;
• an outer tube operatively connected to a first end of said curtain for winding said curtain thereabout for opening said curtain to said opened position and for unwinding said curtain for closing said curtain to said closed position;
• an inner shaft;
• a resilient tensioning means disposed between said outer tube and said inner shaft, a first portion of said resilient tensioning means being operatively connected to said outer tube and a second portion of said resilient tensioning means being operatively connected to said inner shaft, wherein the tension of said resilient tensioning means is maintained substantially constant irrespective of the degree of opening or closing of said curtain to thereby tightly wind said curtain around said outer tube;
• regulating means for regulating the speed of said curtain comprising a speed reduction mechanism having a high speed end and a low speed end, an input shaft connected to said high speed end of said speed reduction mechanism and an output shaft connected to said low speed end of said speed reduction mechanism, wherein said speed reduction mechanism is operable in a first direction and a reverse direction;
• a self-closing mechanism operatively connected to said curtain for moving said curtain to its closed position, said self-closing mechanism incorporating movable means for storing energy as said curtain is moved to its opened position, the stored energy acting through said movable means for urging said curtain to its closed position;
• connecting means for operatively connecting said output shaft to said self-closing mechanism and said inner shaft;
• a brake for preventing rotation of said output shaft thereby blocking movement of said self-closing mechanism;
• and
• releasing means for releasing said brake to free said output shaft for rotation thereby freeing said movable means for releasing the stored energy for urging the door to its closed position.

A door comprising:

• a curtain including a plurality of interconnected relatively pivotal slats aligned in a single direction;
• a guide positioned on one side of said curtain for guiding said curtain for movement between a first or opened position and a second or closed position;
• an elongated rotatable member operatively connected to a first end of said curtain for winding said curtain thereabout for opening said curtain to said opened position and for unwinding said curtain for closing said curtain to said closed position;
• regulating means for regulating the speed of said curtain comprising a speed reduction means for reducing a rotational speed, an input shaft connected to said speed reduction means, an output shaft connected to said speed reduction means, said speed reduction means for reducing the rotational speed of said output shaft relative to said input shaft, a governor mounted on said input shaft for limiting the rotational speed thereof thereby limiting the rotational speed of the said output shaft;
• a self-closing mechanism operatively connected to said curtain for moving said curtain to its closed position, said self-closing mechanism including an inner shaft, an outer tube and resilient tensioning means, wherein a first portion of said resilient tensioning means is operatively connected to said inner shaft and a second portion of said resilient tensioning means is operatively connected to said outer tube, wherein said outer tube is operatively connected to said output shaft and is operatively connected to said curtain, wherein said inner shaft is maintained in a fixed position, and wherein said resilient tensioning means is adapted for storing energy when said curtain is moved to its open position;
• a brake for preventing rotation of said output shaft thereby blocking movement of said self-closing mechanism;
• and
• releasing means for releasing said brake to free said output shaft for rotation, thereby enabling said movable means to release energy stored thereby and urge said curtain to its closed position.

A door comprising:

• flexible means movable between opened and closed positions for covering an opening, said flexible means having first and second ends and defining a surface dimensioned to cover said opening;
• first rotatable means, connected to said first end and defining an outer surface, for receiving said flexible means about said outer surface as said flexible means is moved from a closed to an opened position;
• second rotatable means, engageable with a surface portion of said flexible means disposed between said first and second ends, for causing said flexible means to move between said opened and closed positions;
• and
• means for synchronously rotating said first and second rotatable means, said first and second rotatable means being rotated about respective parallel axes by said rotating means;
• wherein said second rotatable means includes means for storing energy as said flexible means is moved to its opened position, said energy storing means being operable to urge said flexible means to its closed position using energy stored therein.

A mechanism for retracting a flexible door extendable across an opening and having first and second ends and a surface dimensioned to cover the opening, comprising:

• first rotatable means, connectable to the first end of said retractable door and defining an outer surface, for receiving said flexible door about said outer surface as said door is retracted from a closed to an opened position;
• second rotatable means, engageable with a surface portion of said retractable door between said first and second ends, for causing said curtain to move between said opened and closed positions in response to rotation thereof;
• and
• means for synchronously rotating said first and second rotatable means, said first and second rotatable means being rotated about first and second axes, respectively, by said rotating means;
• wherein said second rotatable means includes means for storing energy as said flexible door is moved to its opened position, said energy storing means being operable to urge said flexible door to its closed position using energy stored therein.