Abstract: A vertical screen device for a separator is disclosed. The screening device comprises a vertical cylindrical screen with a feed screw housed within the screen and cooperating with the screen. The feed screw is caused to rotate while the screen is held stationary. The improvements of the invention are provided by having the feed screw make an angle with the surface of the screen over at least a portion of its length. Further, the feed screw is made up partially of a radially inwardly non-yielding portion, and a radially outwardly aligned elastic portion.

Abstract: Vertical screening device (1) having at least one cylinder screen (2) and connectible with its lower end portion (8) to a similar screening device or a drive unit and, with its upper end portion (7), to a similar screening device or a distributor device. The screening device is adapted, together with the other devices connected to it, to be imparted a movement of rotation. The invention is charaterized in that the screening device (1) comprises a bearing device (3) for supporting a feed screw (4) cooperating with the cylinder screen (2). The bearing device (3) is disposed within the cylinder screen (2) and fixedly connected thereto. The feed screw (4) is connected through a link (5) extending outside the periphery of the cylinder screen (2), to a fixed point (6) provided outside the screening device (1) for holding the feed screw (4) stationary.

Abstract: The vertical cylinder screen in a cleaning machine is adapted to be given a rotary motion at oscillating angular velocity. This is obtained with this invention in that the cylinder screen is adapted to be given an oscillatory motion by means of a driven eccentric unit coupled to it and a rotary motion in that the eccentric unit is mounted on a carrier therefor which is adapted to rotate about the center shaft of the cylinder screen.