Abstract In dry copying machines utilizing particulate toner a particle conveying system including a plurality of pneumatic ducts and a blower with a vacuum-type pickup device attached to an inlet of the blower and positioned to remove loose particles from the copies as they egress from the copying machine, a centrifugal separator positioned in the pneumatic system to receive the air and particles from the vacuum pickup device and separate the particles from the bulk of the air, a particle settling chamber having baffles therein attached to the copying machine and receiving separated particles from the separator so as to return them to active use in the copying machine and further having an outlet duct attached to the blower to reduce the pressure therein slightly below atmospheric, and a filter assembly attached to the air outlet of the separator so that air leaving the separator is filtered prior to being returned to the atmosphere. The filter assembly is constructed from an extruded plastic housing having two side walls and a joining wall connected to provide a U-shaped cross section and a pleated filter element connected to the sidewalls opposite the joining wall and end walls formed of plastic while in its formable state and subsequently hardened to provide sealing engagement with the ends of said housing and pleated filter.
A filter assembly comprising: a. an elongated housing having two opposed side walls with inner surfaces and a wall joining said side walls, said housing having a generally U-shaped cross section; b. an aperture through said joining wall forming a gas flow passage for said filter assembly; c. a pleated filter element of gas permeable filter material extending between said two opposed side walls, having a full pleat at each end thereof positioned against said inner surface of the adjoining side wall; d. said housing having clips affixed thereto, said clips having extended ends spaced from said inner surfaces of said side walls to receive there-between in securing engagement said full pleats; and e. end walls affixed to said housing and said pleated filter element and sealing the ends of said housing and pleated filter element against the passage of gas therethrough so that all gas passing through said filter assembly passes through said pleated filter element.
Claim 2
Dependent Claim
157 words
A filter assembly comprising: a. an elongated housing having two opposed side walls with inner surfaces and a wall joining said side walls, said housing having a generally U-shaped cross section; b. an aperture through said joining wall forming a gas flow passage for said filter assembly; c. a pleated filter element of gas permeable filter material extending between said two opposed side walls, having a full pleat at each end thereof positioned against said inner surface of the adjoining side wall; d. said housing having clips affixed thereto, said clips having extended ends spaced from said inner surfaces of said side walls to receive there-between in securing engagement said full pleats; and e. end walls affixed to said housing and said pleated filter element and sealing the ends of said housing and pleated filter element against the passage of gas therethrough so that all gas passing through said filter assembly passes through said pleated filter element.
Claim 3
Dependent Claim
57 words
A filter assembly as set forth in claim 1 wherein the end walls include plastic material formed into walls sealingly engaged with opposite ends of said housing and said pleated filter element while in a formable state and subsequently hardened to maintain said end walls fixedly and sealingly engaged with said housing and said pleated filter element.