In-line filter device for compressed air having mist filter and air collector

Claim 1

An in-line filter device connected in an air line through which compressed air flows, comprising: a partition member having an inlet passage open on a central part of a lower surface thereof, for introducing a flow of the compressed air, at least one intermediate passage formed through a thickness thereof between a central portion and a peripheral portion thereof, and an outlet passage open on a central part of an upper surface thereof, for delivering the compressed air; a lower housing which is closed at one of opposite ends thereof and open at the other end, said lower housing being fluid-tightly attached at said other end thereof to a lower portion of said partition member, and cooperating with said partition member to define a lower enclosed space whose lower part provides a sump for storing a liquid which is separated from the compressed air as a result of condensation or coalescence of vapor or liquid particles contained in the compressed air; first filter means disposed in a central portion of an upper part of said enclosed space, and including a sleeve and a first packing filling an interior of said sleeve, said first packing receiving the compressed air coalescing said vapor or liquid particles into said liquid; second filter means including an annular member disposed radially outwardly of said sleeve of said first filter means, and a second packing filling an interior of said annular member, said second packing receiving the compressed air from said lower part of said enclosed space and directing the compressed air into said at least one intermediate passage; draining means disposed in a bottom portion of said sump, for discharging said liquid from said sump to an outside of the in-line filter device; an upper housing which is closed at one of opposite ends thereof and open at the other end, said upper housing being fluid-tightly attached at said other end thereof to an upper portion of said partition member, and cooperating with said partition member to define an upper enclosed space which communicates with said lower enclosed space through said at least one intermediate passage; a mist filter having an annular porous structure and being disposed within said upper enclosed space so as to cause the compressed air from said at least one intermediate passage to flow through said annular porous structure in a direction from an outside to an inside of said porous structure, for separation of remaining vapor or liquid particles from the compressed air while the compressed air is flowing through said porous structure; and an air collector disposed inside said annular porous structure of said mist filter, and communicating with said outlet passage for delivering the compressed air after being filtered.