Security articulation for door, gate or window - has quadrant shaped channel cut out of frame riser into which fits curved edge of door to prevent catching of finger

摘要

At the hinge the raiser of the fixed door frame has a quarter circle cut from it, while the riser of the door edge at this side has a three quarter circle section. The circle radii are the same so that one fits snugly into the other, the centre of the circle lying on the extension of the inside face of the fixed frame riser so that the leaf can swing through 180 degs. Rods placed vertically in the circle centre and extending up and down through the door leaf into the fixed frame act as hinges or pivots.