Grating in ceiling for ventilation air has several parallel T-section rods fitting in cutouts in U-section supporting rods and stems of T-sections are bent to go through curved parts of cutouts

摘要

The grating has an array of parallel T-section rods (2) held by U-section support rods (1). These rods have semicircular cutouts (10) in the sides (4) of the U-sections near the ends. There are cutouts in the bottom (3) of the U-sections, with narrow end portions extending up the sides. The tops of the T-section rods fit in the broad portions of the cutouts and the stem portions (7) fit in the narrow portions at the ends. The narrow portion at the end of each cutout is curved in the opposite direction, so that the stem of the T-section must be bent to pass through it, thus locking the rod in place.