Abstract: In a hinged security window grating that cannot be opened from the outside but which is readily releasably from within by the lowering of a vertical locking bar that engages the closed grating. The release mechanism includes a tubular member attached to the building wall for slideably engaging the lower end of the locking bar. The tubular member and corresponding point on the locking bar have slots which are engaged by one end of a pivoted lever, the opposite end of which has a pedal which, when depressed, pivots the lever so that it withdraws from the slots to permit the locking bar to vertically drop to release its lock on the grating.

Abstract: Security gratings covering windows of buildings are quickly and reliably opened only from the interior of the building by hinging the grating at a first end and having at the second end short end bars that extend through holes to the interior of the building. A locking bar vertically slideable in bushing members attached to the interior wall has hook portions that extend out and engage the end bars to prevent the grating to be hinged open. The lower end of the locking bars is locked against vertical movement by a quick release pin that engages the locking bar and a fixture attached to the wall near the floor and out of reach of an intruder reaching in the window. To open the grating it is only necessary to pull the pin and vertically move the locking bar to release its hooks from the ends of the end bars.