Abstract: A feeder/transporter having a ported hollow cylindrical vacuum housing and an internal complimentary shaped control valve. The housing is mounted for rotation about an axis located so as to position a sheet receiving outer surface of the housing for movement in a path from adjacent to a tray for supporting a stack of sheets toward a remote location to which the sheets are to be fed. The control valve is non-rotatably supported on the axis of the housing, and is mounted for reciprocable movement along the axis to control the opening and closing of ports in the housing. The control valve has an opening extending for a portion of its circumference with a series of port-blocking tabs extending into the opening.

Abstract: Method and apparatus for producing duplex copies. First and second unfixed images are transferred to opposite sides of a copy sheet before fixing of either image to the copy sheet. The first and second unfixed images may be electroscopic images sequentially formed on a photoconductor by electrophotographic techniques. The first unfixed electroscopic image is transferred from the photoconductor to a first side of a copy sheet, the sheet is inverted while the first image thereon remains unfixed, the second unfixed electroscopic image is transferred to the second side of the copy sheet, the copy sheet with the first and second unfixed images thereon is then transported to a fixing station.