Abstract: The invention relates to a screening machine with a screening drum which rotates about its axis and has a screen made of elastic material. The characterizing feature of the invention is that the screening drum has at least one screening zone which has the shape of a cylinder or truncated cone and the length of which, in order to alternately stretch and relax the screen lining, can be changed in a vibrating manner in the axial or conveying direction.

Abstract: The invention relates to a method and apparatus for sorting out recycled paper pulp obtained from scrap material containing contaminants in the form of large pieces of foreign material such as plastics, adhesives, pieces of rope and the like.The invention avoids the need to disintegrate such large pieces of foreign material prior to their removal.The device of the invention comprises a drum (1) with an horizontal axis (2), an end wall (3) of the drum being fitted with a perforated plate (4) and an helical stirrer (5) having profiled blades rotating in a plane parallel to this plate at a short distance thereof, these blades having a transverse cross-section with a hydrodynamic profile adapted for generating a depression in front of the perforated plate, and a leading edge (6) forming a Bernouilli spiral with a constant angle of approximately 30.degree.

Abstract: The sorting apparatus contains a screen forming at least part of a circular-cylindrical surface and a rotor having a rotor shaft which is coaxially located at the lengthwise axis defined by the circular-cylindrical surface. The rotor possesses clearing blades and propelling blades arranged to follow or trail the clearing blades as seen in the rotary direction of the rotor. The clearing blades each comprise a front-positioned clearing edge which moves along the screen and a run-up surface which is inclined relative to a radial direction defined by the rotor. The run-up surface moves the fiber stock in a direction towards the rotor shaft and provides an open through-passage in the central region of the rotor. The propelling blades extend from the rotor shaft towards the screen and terminate at a distance from the surface defined by the screen.

Abstract: A rotor for a sorting apparatus for cleaning fibrous suspensions such as produced from the making of paper is described. The rotor is equipped with sorter blades which extend substantially parallel to the axis of rotation and are set at a desired angle relative to the direction of rotation of the rotor so as to create a hydrofoil effect. The sorter blades are mounted to one or more supporting walls shaped in a spiral form to provide spiral surfaces which are coaxial with the axis of rotation of the rotor and impart a conveying motion to the fibrous suspension. Upon rotation of the rotor in a fibrous suspension entanglements by impurities are avoided and the danger of the occurrence of a blockage of the strainer used in the sorter apparatus is reduced.

Abstract: A screen panel for vibratory screening machines can consist of at least one cast, injection-molded or vulcanized perforated plate of elastically flexible material, such as plastic or rubber. It has a multitude of screen openings (5) and crosspieces (2, 3, 4) surrounding them which are interconnected forming one piece and thus the perforated plate. A self-cleaning effect can be achieved with such a perforated plate in the area of each individual screen opening (5) by means of a relative movement of the edges of the screen openings in order to extend the self-cleaning effect to as large an area as possible of each individual screen opening (5). For this purpose, at least two of the crosspieces (2-4) surrounding the individual screen openings (5) have a differing bending resistance by means of differing cross-sections and/or reinforcements (8).

Abstract: A screening device having a screen deck composed of two screen frames (11, 27) provided with oblong, parallel screening elements (20, 28), the elements (20) of the first frame being arranged between the elements (28) of the second frame. The second frame (27) rests on the first frame (11). The frames are provided with guide and contact elements (22-26, 32) for guiding and retaining the second frame in a predetermined position on the first frame. The second frame (27) can, in order to free material particles which have jammed between the screening elements (20, 28), be raised freely relative to the first screen frame to a predetermined maximum height, the frames and their screening elements remaining parallel to one another. The frames can be resiliently supported for performing oscillating movements relative to a support frame (5) and relative to one another.

Abstract: A method and apparatus for screening pulp, or like suspensions, having a consistency of about 6-15 percent. The pulp is passed into a chamber having a flat plate screen, and the pulp is fluidized by rotation of a disk, with vanes, mounted adjacent the screen. The disk may be constructed to allow circulation of rejects within the chamber. The chamber may be in communication with a second chamber having a similar screen and disk arrangement, with the rejects outlet from the second chamber in communication with the suspension inlet to the first chamber.

Abstract: An apparatus is disclosed for screening and separating wood chips or the like according to thickness. In the illustrated embodiment, the apparatus comprises two generally horizontal decks mounted one beneath the other, and with each deck having three screening sections disposed in a serial arrangement along its longitudinal length. Each screening section comprises an opening in the associated deck, a stationary grid composed of parallel rod elements disposed in the opening, and a movable grid which is also composed of a plurality of rod elements and which are disposed in alternating relation with the rod elements of the stationary grid. Further, the grids are arranged so that the gaps between the rod elements are parallel and of predetermined uniform separation throughout.

Abstract: A granulation recovery device comprising a vacuum head, a canister removably attached to said vacuum head and a membrane and a support therefor which act as an interface between the vacuum head and the canister. The canister also contains means for diverting a granulation mixture away from the interface during operation of the device while simultaneously separating granulation from the granulation mixture. In operation, the device is attached to an exterior source of granulation loss.

Abstract: This invention provides means to screen long, slender objects from a flowing fluid, and more particularly provides means to clear jammed objects therefrom. The screening means comprises a set of opposed, aligned, undulating surfaces, preferably formed as corrugated plates, located within a conduit, that can be moved apart to permit the removal of trapped debris. The plates are so mounted as to be transversely movable relative to the conduit, and are each movable relative to the adjacent plates so as to permit increasing the separation between adjacent plates when the plates are moved to outside of the conduit. The liquid screening means of this invention can usefully be included in a suction type dredging device, between the inlet nozzle and the pump.

Abstract: Screening apparatus for fractionating material suspensions has a screen gap which is defined by a rotatable member and a stationary member. One of these members is provided with at least one projection which extends into the screen gap to inhibit clogging of the gap with coarse suspension materials. Any coarse suspension materials stuck in the screen gap can be removed from the screen gap by a wiper element extending from the rotatable member and overlapping the screen gap.

Abstract: A separator system for separating grinding bodies and ground material in an agitator mill wherein stationary and moveable or oscillating separator members in a grinding chamber define a variable gap which narrows when a moveable separator member moves against the flow of ground material.

Abstract: An apparatus for screening fibrous stock. A rotor is rotatably mounted within an open ended, cylindrical screen which is mounted in a hollow housing. Fibrous stock is introduced into the housing and rotation of the rotor causes the portion of the fibrous stock that will pass through the screen to do so. Any fibrous stock that passes through the screen is discharged from the housing. The rotor includes a cylindrical body member having a plurality of blade members attached thereto and spaced substantially evenly about the circumference of the body member and radiating outwardly therefrom. Each blade member has a leading edge and a trailing edge with the leading edge spaced farther from the body member than the trailing edge.

Abstract: The stock slurry pulsing rotary foils in a cylindrical paper making machine screen comprise sets which are shorter than the screen and respectively extend from opposite ends of the screen and have their inner end portions alternating in circumferentially spaced but axially overlapping relation. Thereby, the frequency of the hydraulic pulses transmitted directly to the accepts outlet is increased, but the total amplitude of the foil pulses transmitted to the outlet pipe is reduced, and this is accomplished without significant change in horsepower for driving the foil means, as compared with an arrangement of half the total number of foils wherein each foil extends throughout the effective length of the screen.

Abstract: An apparatus for purifying paper pulp in the liquid state by screening. The apparatus comprising a cylindrical fixed screen disposed coaxially with a rotor within a housing. The rotor has longitudinal blades which, in section transverse to the rotor axis, have the general shape of an angle one side of the angle being substantially radial to the rotor and a second side inclined thereto. This apparatus is capable of both centripetal and centrifugal operation, and at concentrations of from 3 to 4%.

Abstract: A classifying apparatus for a suspension, especially for a pulp suspension, having a screen drum, means for feeding the suspension to one side of the screen drum, for removing thickened suspension from the same side of the screen drum and liquid from the opposite side of the screen drum, blades inclined in relation to their direction of rotation so that any one of the ends of the inclined blades is substantially on the same screen drum line parallel to the screen drum axis as the opposite end of some other blade and fitted to sweep at least one surface of the screen drum, and driving means for moving the blades in relation to the screen drum.

Abstract: A method and apparatus for use in separating oversize from on size particles in a mass of particulate materials passed rapidly through a screening device includes a sloping screen mesh having sizing openings dimensioned to be larger than the desired maximum on size particles intended to pass through the mesh. The screen mesh is supported at a relatively steep slope angle and the cosine of the angle of the slope multiplied times the mesh opening size is set up to be substantially equal to the desired maximum on size particles to be passed through the screen mesh. A particle rebound shield is spaced closely above the upper surface of the screen mesh for reflecting and directing particles that bounce off the screen mesh back towards the openings therein.

Abstract: A mechanism for screening a stock slurry for a paper making machine including a cylindrically shaped tubular screen with a stock supply at one end and a discharge at the opposite end for rejected stock and an annular receiving chamber outwardly of the screen for material which passes the screen and rotating axially extending foils within the screen, each foil having a rib projecting radially inwardly and extending in a helical direction at an angle to the foil to move the stock from the supply end of the screen to the discharge end.

Abstract: A method of screening paper fiber stock incorporating a screen member having generally circular perforations and a rotor supporting vanes movable in the supply chamber, the rotor vanes are spaced from the screen member by a substantial distance (3/16"-1/2") to establish a tubular layer of stock of corresponding radial thickness adjacent the screen member, the rotor is operated at high speed to develop strong hydraulic shear forces in the tubular layer of stock causing tangential orientation of predominantly two-dimensional contaminant particles, and ribs on the inlet side of the screen member cause the stock to be continuously recirculated in the supply chamber to prevent undue increase in the consistency of the stock in the tubular layer, thereby enabling the screen to operate effectively at high capacity and high stock consistencies.

Abstract: This is a new hydrofoil structure. The hydrofoil has a radial outer surface having a circumferentially curved portion conforming to and closely spaced from the inside surface of the screen plate. The hydrofoil's radial outer surface also has a flat surface radially inward from the curved portion.The radial outer surface of the hydrofoil is constructed to convey along the flat surface any particles or knots which get in the space between the flat surface and the inner surface of the screen plate.

Abstract: In a screening machine of the type having a perforated cylinder through which the material being screened is passed and a rotor for maintaining the cylinder perforations open, failure of the cylinder due to torsional forces imposed on it by rotation of the rotor is prevented by providing several beam-like cantilevers which extend longitudinally of the cylinder and resist the twisting, torsional forces imposed on the cylinder during screening operations. Intermediate reenforcing rings, which are designed to withstand radially directed loads imposed on the cylinder, are restrained against movement longitudinally of the cylinder by means of clips which are welded to the cantilevers on opposite sides of each of the rings. The cantilevers, therefore, also serve as an area on the cylinder to which the clips can be welded, eliminating the necessity of making welds at undesirable locations near perforated portions of the cylinder.

Abstract: Screening apparatus for paper fiber stock and other fiber suspension is especially designed to handle relatively suspension containing stringy material. A perforate screen cylinder forms the outer wall of the supply chamber for the stock to be screened, and a rotor operates in the supply chamber and includes vanes which travel in spaced relation with the inner wall of the screen cylinder. These vanes are supported on the rotor hub by imperforate arms of substantial axial extent which act as propeller blades to maintain a high rate of circulation of the stock within the supply chamber and also to direct the stock toward the reject collecting chamber from which stock is continuously discharged at a high volumetric rate approaching or equal to the rate of discharge of accepted stock. Helical ribs on the inner surface of the screen cylinder aid in channeling the flow of reject-containing stock toward the reject outlet.

Abstract: A negatively pressurized rotating hollow foil pulse device having a curved leading surface, a V-shaped trailing surface and one or more openings in the trailing surface is placed in close proximity to a pulp screen for removing oversized pulp reject material. A rotating disc seal separates a reject compartment from the material to be screened.

Abstract: A shuffle feed sizing structure wherein articles are progressed from valley to valley over a shuffle feed mechanism and as they progress the article advancing face of the shuffle feed member provides a sizing opening of a given width so that the articles small enough to fall through the opening are discharged downwardly beneath the shuffle feed at this point. Various widths of sizing opening are provided between the faces of the shuffle feed as required and the largest articles are discharged over the end. Means are also provided for ejecting articles from a sizing opening if they tend to become wedge or if they remain in front of the sizing opening but are too large to pass through the opening.

Abstract: A continuous digester in which liquor is drained, at various levels, through a screen into a compartment formed by half rings attached to the interior of the digester. The compartment is provided with rotating vanes, which backwash the screen by pulsing liquid therethrough. The digester includes a lower cone, provided with an impeller and compartment for introducing and circulating liquor for "cold blow" of product.