Patent ID: 7473167
Filing Date: 2009-01-06
Classification: F24F

Abstract:
1. A security ventilation grating comprising: a. a perforated ventilation grating having an outer surface facing a room and an inner surface facing a ventilation duct; b. a body, said body having a base with a planar surface covering said inner surface of said ventilation grating and an outer wall extending into said ventilation duct from said base, said body further including a plurality of inner passageways extending from said base to said outer wall, each of said passageways having a first portion extending from said base in a first axial direction perpendicular to said base, and a second portion extending from said outer wall in a second axial direction to intersect said first portion within said body, said first and second axial directions being perpendicular with respect to each other; and, c. means to affix said body over said inner surface of said ventilation grating.