DOOR BLOCK Russian patent published in 2000 - IPC

FIELD: construction, in particular, door blocks. SUBSTANCE: door block has a metal door frame secured in the wall opening with a frame ledge confining the door opening with working surfaces chambered outside, door leaf hinge-joined to the door frame and having a trapeziform section in the horizontal plane, and a closing device fixing the door leaf in the position, in the which the end surfaces of the door leaf are pressed to the working surfaces of the frame ledge having the shape of the surfaces adjoining them. The working surfaces of the frame ledge have the shape of the are section of convex cylindrical surface. The end surfaces of the door leaf pressed to the working surfaces of the frame ledge have the shape of the are section of concave cylindrical surface. EFFECT: enhanced reliability of room locking at an attempt of breaking in. 6 cl, 5 dwg