Patent ID: 8881455

Claim:
An automatically closed fire protection louver device installed on an outer surface of a wall or outside of a window, the louver device comprising: a control unit including a main body formed in a shape of a hollow cylindrical tube having a front end hollow and a rear end hollow, which are hollows, respectively formed at a front end and a rear end, in which a lower portion of the main body is open to form a fuse room connected to the front end hollow, and a plurality of control pins is formed at an upper part of the main body in a row, a fuse inserted in the fuse room and broken by heat at a predetermined temperature, a front side fixing rod inserted in the front end hollow, having a rear end tightly attached to the fuse and a front end exposed to outside of the front end hollow, a spring inserted in the rear end hollow, and a rear side fixing rod inserted in the rear end hollow, having a front end tightly attached to the spring in a state of maintaining a compressive force of the spring and a rear end exposed to outside of the rear end hollow; a plurality of blades, each blade formed substantially planar with an oval cross-section when cut perpendicular to the longitudinal axis of said blade, in which each of the blades has a blade rotation axis protruded at both ends, and a blade lower portion is rested or hinge-coupled in a space between the control pins; and an exterior frame configured of a front side plate formed with a front side fixing rod insertion hole at a center so that a front end of the front side fixing rod may be inserted and fixed in the front side fixing rod insertion hole, a rear side plate formed with a rear side fixing rod insertion hole at a center so that a rear end of the rear side fixing rod may be inserted and fixed in the rear side fixing rod insertion hole, and two side plates respectively formed with a plurality of blade rotation axis insertion holes at regular intervals in a row so that the blade rotation axis may be inserted and rotated, in which both ends of each side plate are installed to be respectively attached to an end of the front side plate and an end of the rear side plate, in which if heat is applied to the fuse when a fire breaks out, the fuse is broken, and the main body moves forward by the spring so that the blade lower portion rested or hinge-coupled in a space between the control pins may move together with the main body, and thus the plurality of blades are rotated and closed.