Air filter housing for filtering suspended substances

Claim 1

An air filter housing having a turnbuckle, a pressure frame, a filter element mounted on said frame located within said housing, the filter element being designed for the purification of air of toxic or radioactive dust or gases, said housing having frame-like contact pressure surface against which said element is made to bear by means of said turnbuckle which includes a spindle, said spindle lying parallel to said surface beneath said filter and being rotatable about its longitudinal axis, said spindle having oppositely oriented threads at its respective ends, a threaded nut in threaded engagement with each of said respective threads capable of movement toward and away from one another during rotation of said spindle, a crank connected to said spindle for rotation thereof, said spindle being located centrally of the opposite side walls of said filter element, a tongue element for each said nut, each said tongue element being mounted on said housing and having portions of each thereof lying adjacent opposite sides of each said nut for preventing rotation thereof, each said portion of each said tongue element having a horizontal elongated opening therein, a guide element for each said tongue element, each said guide element being mounted on said frame and each having a cheek lying adjacent each said tongue element portion, each said cheek having a sloping elongated opening therein, said openings of one of said guide elements sloping toward said filter and toward the openings of the other one of said guide elements, each of said nuts being rectangular in cross-section and having a transverse opening therein, and a guide bolt in engagement with said transverse opening and extending through said elongated openings of said tongue element portion and of said cheek lying at each said side of each said nut whereby, upon rotation of said crank for moving said nuts away from one another, said filter is moved into engagement with said surface as said tongue elements move along their respective openings.