DOOR ASSEMBLY Russian patent published in 2007 - IPC E06B5/16 

FIELD: construction, particularly door assemblies for industrial and residential buildings, namely for passive door opening protection against free flame.

SUBSTANCE: door assembly comprises door frame and door leaf hinged to door frame. The door frame includes thin steel sheet shell connected with each other and heat-resistant insulation layer arranged between the shells. The door leaf has stiffening ribs made of steel profiles. Door frame is formed of two members and heat-resistant instillation layer arranged in-between. Door frame has two stiffening ribs fastened to end surface of inner door leaf shell through pads and separated from the shell by means of heat-resistant insulation layer. One rib extends along inner shell end from the side of pocket adapted for locking mechanism receiving. The second rib passes over inner shell end from the side of hinge used for door leaf connection. The heat-resistant insulation layer is formed of pressed basalt fiber panels fastened to surfaces of door leaf and door leaf members. The panels are composed of heat-resistant mastic and liquid glass taken in the ratio 1:1. Space defined by door leaf shells is filled with strips cut out of pressed basalt fiber panel having thickness equal to distance between the shells. Door frame members and door leaf shells are assembled with the use of steel rivets having pull-out pin.

EFFECT: increased fire-resistance.

2 dwg