Abstract: In combination a unique design of inflatable bladder screen tensioning device, a plurality of securing pins, and a plurality of cotters. The inflatable bladder is positioned between a first elongate plate and a second elongate plate such that as the bladder is inflated the first elongate plate and the second elongate plate are forced apart. A plurality of openings extend through the first elongate plate, the inflatable bladder and the second elongate plate. The securing pins are of such a length that they can extend transversely through a screen engaging clamp, a screen retaining frame and thereafter through the openings in the first elongate plate, the inflatable bladder and the second elongate plate. Each of the securing pins is comprised of a shaft having a first end and a second end. A head is positioned at the first end such that the head engages screen engaging clamp. A transverse opening is positioned at the second end.

Abstract: A vibratory screen for a vibratory screening machine consisting of a plate having a plurality of spaced openings therein, a coarse screen located in contiguous relationship to the plate, a fine screen on top of the coarse screen, a finer screen on top of the fine screen, and a topmost screen which is less fine than the finer screen and epoxy binding all of the foregoing screens to the plate at the borders of the openings. A vibratory screening machine having a tank for receiving a liquid-solid mixture, a plurality of screens of the foregoing type mounted to produce a sealed partition in the tank, an inlet conduit for supplying a liquid-solid mixture to the screens at a rate to maintain a head of the liquid-solid mixture above the screens, a vibratory motor attached to the tank to vibrate the tank, an outlet in the tank below the screens, and a liquid trap located at the outlet to thereby prevent air from entering the chamber in the tank below the screens and to draw a slight vacuum in the chamber.

Abstract: A vibrating screen apparatus includes a frame and a screen having a first end coupled to an anchor beam which is rigidly coupled to the frame. The apparatus also includes a tension control assembly coupled to a second end of the screen for tensioning the screen to substantially a predetermined tension. The tension control assembly is rotatably coupled to the frame spaced apart from the anchor beam. The tension control assembly changes the tension of the screen upon rotation of the tension control assembly relative to the frame about an axis of rotation. The apparatus further includes an adjusting mechanism for moving the tension plate in a direction normal to the axis of rotation of the tension plate to compensate for nonuniform tension of the screen.

Abstract: A reinforced screen rail is described which is useful for retaining a screen in a screendeck. The screen rail includes spaced apertures corresponding to apertures in the screen deck. A metal layer is secured along the length of the screen rail to increase its useful life.

Abstract: An assembly comprises a rectangular principal frame (12) of moulded plastics material and subdivided by crosspieces (14, 16) to form sub-areas (18). Each sub-area receives as a releasable snap-fit a plastics moulded insert (20) in the form of a sub-frame carrying one or more tensioned screen meshes (FIG. 1). A peripheral sealing gasket may seal the joint between each sub-area (18) and the insert (20).

Abstract: System for mounting screen and other panels in vibrating and other screening apparatus in which longitudinal channel members interposed between laterally adjoining panels and anchored to apertured longitudinal supports, have space normally upright flexible sides each yieldably flexing inwardly in response to pressing of a panel edge thereagainst for seating the edge in an external groove in the channel side, the channel side, the channel member containing a longitudinally coterminous cavity opening upwardly through a relatively restricted slot, and the panel edge being releasably lockable in the channel groove by a T-shaped lock member having a stem insertible in said cavity through the slot for forcing the flexed side to return to upright edge-locking position.

Abstract: A screen formed of a screen frame (10) with screen cloth elements (11) mounted after each other. The screen cloth elements (11) are fixed in the screen frame by snap lock (16, 17; 18). One part (16, 17) of the snap lock is integrally formed with the screen cloth element (11) and arranged adjacent one end thereof. The other part (18) of the snap lock is a thickened portion at the upper edge of a supporting element (19) in the screen frame (10). The opposite end of the screen cloth element rests on a projecting abutment surface (20) on the supporting element (19) and is clamped between this abutment surface and a projecting edge portion (22) of the preceding screen cloth element.

Abstract: A screening apparatus comprises an elongated support frame; a mobile, deformable sieve consisting of a sieve mat extending along the length of the support frame and having lateral edges; and a series of alternatingly immobile and mobile sieve mat carriers mounted on the support frame and extending transversely to the length of the support frame, the sieve mat being affixed to the carriers and the mobile carriers being movable with respect to the support frame in the direction of the length of the support frame, the lateral sieve mat edges extending transversely to the carriers and being raised to form rims for the sieve mat.

Abstract: A high speed stock thickener has a foraminous endless wire. The stock thickener is of the type in which an open mesh endless wire is trained over a pair of rolls and paper stock to be thickened is applied between the wire and the rolls and is carried on an inside surface of the wire for dewatering, particularly at the regions where the stock is carried between the wire and a roll. The improved wire is formed with a width greater than that of the rolls with a marginal edge of the wire extending beyond the face of the rolls. A guide belt is attached at each of the marginal edges of the wire and runs with a side wall in engagement with the end of the adjacent roll. The guide belts are attached to the wire by an adhesive bond between the backs of the belts and the adjacent wire surfaces, and by a continous thread which is sewn through each belt from the bottom of the belt and through the back thereof and into the wire.

Abstract: A vibratory conveying and separating apparatus and a clamping device therefor are disclosed. The apparatus includes a conveyor bed which supports processing screens which convey and separate material being processed. The bed is vibrated in a forward and upward direction at a predetermined forward and upward angle of inclination. At least one releasable clamping device engages between the conveyor bed and processing screen to provide a releasable clamping force against the screen for clamping it to the conveyor bed. The clamp is mounted or positioned to orient the releasable clamping force substantially parallel with the predetermined forward and upward angle of inclination.

Abstract: A wood particle screen particularly useful for separating fines from wood chips in which a bed of flexible foraminous material having holes therein sized to permit fines to pass therethrough is flexibly mounted for receiving a flow of wood chips and fines thereon. Beater rolls are disposed beneath the screening bed, each including a plurality of spaced beater bars so positioned as to contact the bottom of the screening bed as the bars rotate through the uppermost position of the rolls.

Abstract: A lock mechanism for use with a screen having a generally square or rectangular configuration and elongated hooks or flanges along two opposed side edges thereof, and rails which extend along and engage the hooks. The lock mechanism comprises at least one arm and a crank. The arm has an outer end coupled to a rail and an inner end pivotably connected to the crank. The crank is rotatable about an axis and it is pivotably connected to the arm on an axis which is spaced from the axis of rotation. Rotation of the crank in one direction causes the arm to be extended outwardly and stretch the screen; rotation of the crank in the other direction retracts the arm and relaxes the screen. A lock is provided between the arm and the crank to hold the arm extended, and a spring is preferably provided between the arm and the associated rail. Preferably a second arm, connected similarly to the first mentioned arm, connects the crank with the other rail.

Abstract: A mounting system for removably attaching elongated screen rails to upright side panels of a screen deck for screening crushed rock and gravel. A method for suspending a screen rail within the screen deck is disclosed which avoids the need to remove the screen rails when changing screens. In one embodiment, a plurality of anchors are secured to one side of each screen rail, and bolts are used to secure the rails to the side panels. The anchors each include an opening which is larger at the top than at the bottom to allow the head of the bolt to be readily and easily captured by the anchor. The mounting system is much easier to use and much more rapid than previous systems.

Abstract: Mounting system for substantially increasing the wear life of a screen panel which is adapted to be vibrated, utilizes elastomeric material, such as urethane, to isolate the vibrating mechanism from direct contact with the screen panel. An elastomeric wear strip is bonded to screen wires on the underside of the screen panel. A recessed channel formed in the bottom of the wear strip is adapted to engage an upper contact surface of a rigid vibrating bar member, while the side edges of the channel extend downwardly over the sides of the rigid vibrating bar member to prevent abrasive material which has passed through slots in the screen panel from entering the contact area between the recessed channel and the upper contact surface. The upper contact surface of the vibrating bar member is preferably covered with elastomeric material and crowned so as to cause the screen panel to become curved when its side edges are forced down by a pair of hold-down bars.

Abstract: A screen assembly, the process for its manufacture, the apparatus used in the process and an adhesive presenting a system and the final product for accurately tensioned bonded screens. The screens include a screen frame and screen cloth bonded thereto by adhesive using bisphenol F epoxy resin, amine adduct hardener, a substantial percentage of amorphous silica and small amounts of glycerin and fumed or precipitated silicon dioxide. Titanium dioxide may also be employed for color. A screen assembly apparatus includes a screen cloth tensioning frame and a platform positionable adjacent a tensioned screen cloth. The platform includes heating elements about the periphery of a sheet heater on a left table. The heating elements receive a screen frame which can be lifted into contact with a screen cloth in the tensioning frame. The sheet heater approaches the screen cloth itself. A thermal control cycle is presented which allows the screen frame to cool prior to the tensioned screen.

Abstract: In a sector-shaped screen segment for disk filters or thickeners with a folded screen for thickening fiber suspensions comprising a frame, two screen carriers and a screen resting on the outer sides of the screen carriers, manufacture is rendered simpler and less expensive by the frame and the screen carriers forming an integral molded part in which the screen is embedded in the molding process.

Abstract: This invention is concerned with an improved structure for the conventional vibro separator which features:A. A novel sereen assembly structure: An additional coarse screen (2-16 mesh) is employed for supporting purpose. It will be secured on a special designed screen frame in order to keep the screen surface in a flat manner. And then the main screen (fine mesh) can be put flatly on coarse screen. It is to be fastened by folding and pressing tight the outside edge into the position between the flanges of spacing frames without using any bolt on welding.B. A new designed ball tray assembly: A certain number of plastic rings are freely added in the ball tray as barriers to confine the tapping balls into certain groups in order to even distribute the tapping balls. And a simplified structure for ball tray assembling is designed with only putting the tray on the flange of lower spacing frame and to be held in position by the inner shoulder cutting space at the bottom of screen frame.C.

Abstract: An improved tensioning assembly for vibratory screens includes a rigid frame, at least one classifying screen in the frame, an anchor for anchoring one end of the screen, and a rotatable tensioning assembly at the other end of the screen for both anchoring the other end of the screen and tensioning the screen by rotation of the rotatable assembly. The anchor at the one end of the screen includes a plurality of threaded adjustment members spaced along the length of the anchor for flexing the anchor to selectively and incrementally further adjust the tension on the screen to compensate for tension variations across the width of the screen due to torque differentials in the rotatable tensioning assembly.

Abstract: A transmission fluid filter assembly in which the marginal peripheries of two sheet metal housing members are crimped into a plied peripheral structure which includes therein the abutting edge portions of a folded filter media sheet member along three of the four sides thereof. The plied peripheral structure is formed by bending a first marginal free edge portion of a first sheet metal member over a second marginal free edge portion of the second sheet metal member in compressing relation with respect to the abutting edge portions of the filter media sheet member. Therafter, the plied peripheral structure is angularly bent intermediate the bent-over outer edge and the free edge of the first marginal edge portion in a direction to form an included angle of 90.degree. between the exterior surface of an outer section and the exterior surface of an inner section of the first marginal edge portion.

Abstract: A method of tensioning screening material on a tension frame for use in a silk screen process including the steps of (1) squaring the material, (2) attaching the material to rotatable frame members along a portion of their length by adhesive (3) rotating the frame members until the appropriate tension is reached, and (4) securing the frame members in position. The fabric may be retensioned without removal. The frame includes four rotatable cylindrical elements including a plug at each end which has a plurality of radial bores for rotation by a spanner wrench.

Abstract: A basket 1 of vibratory screening apparatus comprises inflatable elastomeric member 3 positioned to overlie a part of a screen member 5, 7 mounted in the basket. Inflation of the inflatable elastomeric member 3 causes it to press against a screen frame 7 of the screen member, clamping it against a support 9, 29 of the basket 1. Preferably the inflatable elastomeric member 3 is deflatable and a reservoir 19 may be provided for vented inflation fluid. The screen member may be pre- or post-tensioned. The basket 1 may comprise supports 29 and inflatable elastomeric member 3 positioned to press against parts of the screen member remote from its periphery.

Abstract: The frame member for pressurized screening device includes an inflatable tube disposed along and outwardly of the peripheral wall of the frame. A screen is stretched over an opening in the frame and extends above the peripheral wall and the inflatable tube so that the inflatable tube can be brought into contact with the screen to impart tension to the screen. The inflatable tube is only inflatable in a direction transverse to the direction of the stretching of the screen and in such a manner as not to touch the holder member. A holder member is removably mounted on the screen attaching portion of the frame to sandwich the screen between the upper surface of the screen attaching portion and the lower surface of the holder member.

Abstract: A clamping device for a screen member in vibratory screening apparatus comprises a frame member 1 on which is mounted an inflatable stocking 7. In use, the clamping device is inserted into the basket 21 of the screening apparatus so as to overlie the screen member, and the inflatable stocking 7 is expanded so as to press the screen member against a portion 17, 19, 31 of the basket 21 while the clamping device reacts against a further portion 17, 19, 33 of the basket 21. This pressure from the stocking 7 holds the screen member in place. Preferably the screen member has a screen 13 mounted in a frame 15 and the stocking 7 presses against this screen frame 15. The stocking 7 may press against the periphery of the screen member only or may press against other parts of the screen member as well.

Abstract: A rubber wear layer is molded to a metal sheet, which is relatively thin, in comparison with a side rail for tensioning a vibrating screen, then attached to the side rail, as above a flange which provides a connection with the screen. The rubber layer and sheet may be wider than the width desired for the rail, in which event the wear layer and sheet are trimmed to the desired width, as by shearing. The rubber layer may also have a width less than the sheet, so as to leave a lip along one edge. The aforesaid attachment is made by pins propelled by an explosive charge through the bonded layer, the sheet and the plate at spaced positions. A head of each pin abuts the sheet and the portion which extends past the plate is removed, as by grinding. The sheet may be additionally attached to the rail by spot welds at spaced psitions on the lip, which prevents the heat of welding from adversely affecting the rubber. The lip is placed on the plate opposite the flange which connects with the screen.

Abstract: An improved classifying apparatus and assembly for the tensioning of vibratory screens includes a rigid frame, a pair of classifying screens in the frame and means for tensioning the screens. The improvement in the means for tensioning the screens includes a stationary anchor at one end of the screens and elongate rotatable elements adjacent the other ends of the screens. Levers are mounted to the ends of the rotatable elements outside of the frame and a tensioning cable extends between the levers. A tensioning member is positioned in the cable which, when adjusted, rotates the rotatable elements to simultaneously and uniformly adjust the tension on the screens.

Abstract: A filtering screen is described comprising: a first filter mesh, a second filter mesh having a different mesh size from the first and overlying the first mesh, and an apertured support to which both of the meshes are bonded so as to maintain the two meshes in tension, the tension in one of the meshes being greater than that in the other. At least one other filter mesh may be bonded over the first two meshes. The support may comprise a plate of fiber reinforced material having apertures formed therein which are much greater in area than the openings in the filter mesh, or a sheet of metal in which apertures are formed and in which edge regions of each aperture are turned through approximately 90.degree. to extend normal to the plane of the sheet from the underside thereof to increase the rigidity of the sheet. The frame may alternatively be a honeycomb structure or an apertured metallic plate, the filter meshes being joined to the surface of the frame.

Abstract: A device for fastening a closed casing, such as a wire cloth, which should form the circumferential surface of a cylinder, such as a screening drum, has a supporting member with a circularly cylindrical outer surface which is intended to be inserted in the casing at one end thereof and has substantially the same circumference as the casing. The supporting member has a circumferential groove in its outer surface. A circumferential engagement element which is made of an elastic material is so mounted in the groove that its outer surface is located on substantially the same level as the outer surface of the supporting member. A mounting ring is disposed around the engagement element.

Abstract: A vibratory screening apparatus for removing suspended solids from liquid comprising a first mesh screen having openings with first and second dimensions for receiving the suspended solids thereon, a second mesh screen in superimposed abutment with the first screen and having openings with a third and fourth dimension perpendicular to the first screen openings, the third dimensions being larger than the first dimension and the fourth dimension being smaller than the second dimension of the first screen openings, and a vibratory source coupled to the abutting screens for vibrating the screens whereby the openings of the second screen effectively prevent suspended solids from becoming lodged in the openings of the first screen.

Abstract: The invention relates to a screen surfacing with exchangeable screen elements fastened juxtaposed, which are fastened on a load-bearing substructure. A plastic profile (2) which engages under the edges of at least two mutually adjacent screen elements (14, 15) is fastened on the load-bearing substructure (1) in the region in which two adjacent screen elements (14, 15) adjoin mutually. A second, upper profile (8) is fastened detachably over this plastic profile (2), and a screen element (14, 15) is retained and clamped between the first and second profile on each of two sides.

Abstract: A vibratory screen structure which is rectangular in plan employing pretensioned screen panels and a pneumatic tube seal beneath the panels. Restraining members are positioned on two sides of the screen panels to hold the screen frames in position on the pneumatic tubes when sealed. The remaining sides are unrestrained and bow under the pressure of the pneumatic tubes to create a crown in each screen panel.

Abstract: The method and apparatus for separating materials includes a feed splitting assembly (27) which evenly divides the materials to be separated into equal parts for inputs to a like plurality of screen assemblies (16, 17, 18). These inputs are evenly distributed across the width of some of the screen assemblies (17, 18) by manifolds (44, 51). One of the screen assemblies (16) can receive the input directly through an aperture (40) in the feed splitting assembly (27). The material not passing through the screen assemblies (16, 17, 18) is collected at one location and the material passing therethrough is transmitted to a common discharge spout (55).

Abstract: A vibratory screen separator has cylindrical cleaner elements engaging the lower surface of a horizontal screen with the cleaner elements having a center of gravity offset from their longitudinal axis so that vibration imparted to a supporting perforated surface effects enhanced movement of the cleaner elements. Screen clamp means are pivotally mounted to swing to an external position with respect to a floating tub assembly in which the screen is positioned to permit removal of the screen and a subsequent removal for repair or replacement of a unitary vibrator unit mounted in a housing extending axially below the screen.

Abstract: A screening basket has one or more screen decks and has upright side walls integrated with cross beams. A side beam, at approximately the center of gravity of the basket, is integrated with each of the side walls as well as with the cross beams to provide a unitary, rugged basket capable of vibratory movement on a support frame. A pair of cross shafts extend transversely of the screening basket and project beyond the side walls. These shafts are journaled in the side beams and have one projecting end geared together for opposite rotation. These projecting ends carry eccentric weights of different mass to provide an oval vibratory stroke of the screening basket upon rotation of the shafts. Adjusting mechanism is provided to adjust the relative position of the weights on the shafts to vary the angle of stroke. These weights are arranged to receive auxiliary weights to vary the amplitude of vibratory stroke as well as the shape of the stroke.

Abstract: Method and apparatus for printing a design with a stencil screen including a resilient membrane formed by reversely-bent portions in the screen between a desired pattern defined by a paint-pervious opening in the screen and edge portions of the screen. The reversely-bent portions of the screen are filled with an elastomeric material and extend beyond the bent portions of the screen. A coating of an elastomeric material may be applied to the outside areas of the reversely-bent portions of the screen and adhered to the elastomeric material in the pocket of the screen by permeating the screen openings.

Abstract: A flat sieve, or a part thereof, has a flat body of elastic material with a rectangular (or square) frame spanned by a plate of lesser depth with a multiplicity of throughgoing parallel slots and intervening rows of shorter slots interrupted by solid transverse webs which are integral with crossbars intersecting only the lower portions of the longer, throughgoing slots. The length of the shorter slots may be about one-tenth that of the longer slots.

Abstract: Vibratory screening apparatus wherein a filtrating cradle incorporating screens is vibrated on a machine base, and wherein a bottom screen (56) in said cradle (12) can be withdrawn between an upper support (64) on said cradle and an intermediate support (54) on a bottom screen frame (52), which frame is also withdrawable from the machine on a lower support (62) on the cradle, hydraulic expander means (60) being provided to act on the lower support so that, in the inserted position of the bottom screen frame, the opposed sides of the bottom screen can be clamped between the upper and intermediate supports, locking the bottom screen and its support in position.

Abstract: The invention provides a screening arrangement including a screen deck constituted by a non-stretchable, flexible screen cloth material defining a feed end and a discharge end. The feed end and discharge end are secured to mounting formations associated with a frame and the association is such that in use the screen deck may be reciprocated between a taut state and a slack state. The screen deck is located at an angle to the horizontal sloping downwardly from the feed end to the discharge end. The arrangement of the present invention has a high resistance against blinding of the screen deck.

Abstract: A vibrating screen used for the fine screening of solids from a slurry containing solids includes a base, a screen box having feed end and discharge end with said screen box being resiliently supported on the base, and a drive for vibrating said screen in a generally longitudinal direction. The screen includes at least two overlying layers of relatively fine mesh screen cloth. A tensioning device is connected to one end of the screen cloth for tensioning the screen cloth in a direction parallel to the direction of motion of the screen cloth.

Abstract: Apparatus for supporting screen (12) in a screening machine (10) that will permit long-life of the screen even when subjected to heat and vibration. The screen or wire cloth edge is folded over (30) and fastened or joined (42, 44, 46), with a metal rod (32) inserted down through the foldover space (34). Spring clips (40) or other adjustable tensioning devices attach the steel rod (32) to the screening machine frame (50), thus placing the screen (12) in tension.

Abstract: A plurality of truss-like supports are secured, as by welding, and in spaced relationship, to the underside of a screen cloth. The supported screen cloth is then removably secured in position in a vibrating frame to form therewith a vibrating screen. Each truss-like support includes a support rod formed of wire rod of predetermined diameter disposed with a major portion thereof spaced from and substantially parallel to the plane of the screen cloth, and with end portions thereof merging into the plane of the end pieces of selected wire rods forming the screen cloth and being welded thereto. A spacer wire, formed from wire rod of a diameter less than that of the support rod and to an approximate sinusoidal configuration, is disposed so that the upper tips, formed by the sine configuration, are welded to the bottom surface of the screen cloth and so that the lower such tips are welded to the upper surface of the support rod.

Abstract: An improved screen separator which employs orbital motion for the positive removal of solids from liquids, such as drilling mud. A tensioned screen is mounted horizontally at it peripheral edges between parallel side members of a framework. A cushion rail mounted between the side members carries a resilient screen cushion in tight engagement with the screen. The unique screen cushion has an elongated body with a longitudinal slot receiving the lower edge of the cushion rail. The body has diverging sides which terminate at flared lips at each edge of the concave bottom side of the body. The body produces a downward bow in the screen and the bottom side surface conforms precisely to the the bowed screen. As a result, abrasive solids can not be trapped between the screen cushion and the screen. In addition, the body has diverging sides which divert solids from the screen cushion laterally onto the adjacent screen for separation from the liquid being purified.

Abstract: A material separating device (10) includes a frame member (13) which carries a plurality of vertically arranged support members (19-23). Each of the support members (19-23) includes a plurality of support rods (19A-D, 20A-D, 21A-D, 22A-D, 23A-D). Screen elements (24-28) are stretched by adjustable tensioning devices (30) over each of the support members (19-23) to form screen panels (24a-e, 25a-e, 26a-e, 27a-e, 28a-e) between the support rods (19A-D, 20A-D, 21A-D, 22A-D, 23A-D). Each successive screen panel (24a-e, 25a-e, 26a-e, 27a-e, 28a-e) is inclined at a greater angle than the preceding screen panel (24a-e, 25a-e, 26a-e, 27a-e, 28a-e) so that material being separated moves progressively faster as it traverses each screen element (24-28).

Abstract: Apparatus for separating solid materials from mixtures having solid materials therein, including a wire mesh screen the two opposing edges of which are retained by elongated rigid retainer assemblies against which oppositely directed forces may be applied for placing the screen in tension. Each of the rigid retainer assemblies may comprise: a first rigid retainer member having an elongated flat base portion from one edge of which upwardly projects a curved rib portion providing an elongated arcuate convex surface; a second rigid retainer member having an elongated base portion from one edge of which upwardly projects a curved rib portion providing an elongated arcuate concave surface; and a third rigid retainer member including a flat elongated base portion from one edge of which upwardly projects a rib portion for disposition between the elongated arcuate convex surface of the first retainer member and the elongated arcuate concave surface of the second retainer member.

Abstract: An apparatus for separating curd fines from whey including a closed housing having an inlet to receive whey that contains a substantial portion of curd fines. The whey is introduced onto an inclined delivery trough and is discharged from the lower end of the trough onto a stationary inclined screen which is inclined in the opposite direction from the delivery trough. In passing from the delivery trough to the screen the whey passes through a slot which distributes the whey in a thin layer over the screen. In flowing down the screen a portion of the whey drains through the screen and is collected in a whey bin, while the remaining portion of the whey and fines, in the form of a slurry, is collected in a separate bin and can be returned to the cheese making vat.

Abstract: A drum type screening machine has a centrifuging rotor within it. A perforated retaining element is carried by the shaft between a feed inlet and an entry region of the drum. Use of the retaining element prolongs the screen life so much that tension adjustment become necessary. Provision is made for this to be done from outside of the machine. The screening drum has a pair of rings which support the screening cloth and which are held apart at an adjustable distance by tensioning bars. One ring is supported within an end member of the machine housing and the other on support means within the housing. Each bar is externally threaded, e.g. by way of an extension sleeve that is axially fast with the bar. The sleeve is engaged by an internally threaded nut which is axially fast with the end member of the machine. The sleeve extends through that nut and through the end member to the outside of the machine.

Abstract: A plurality of weighted springy arms are formed integral with, and so as to extend laterally, to one or both sides of, a resilient mounting strip that is disposed beneath, and in contact with, the lower surface of the screen deck of a vibrating screen. The intended vibrating action of the vibrating screen induces an oscillating movement of the weighted springy arms to effect a rapping action of the weighted ends of the arms against the undersurface of the screen deck to loosen material which may have lodged in or plugged the screen openings and to unclog same.The resilient strips disposed on the extreme sides of the screen need only have weighted springy arms on the side thereof towards the central portion of the screen deck if space on the other side of the strip does not permit proper disposition and action of such an arm; while the strips disposed in the central section of the vibrating screen have arms extending from both sides of the resilient strip.

Abstract: A change device for sieves used for filtering plastic materials. The change device comprises a sieve holder having a bore for the throughflowing material and a slot extending transversely thereto, in which there are sealingly retained in work position sieve supports or carriers containing sieves. By means of a work cylinder it is possible, without interrupting the transport of the material which is being processed, to eject and replace the contaminated sieve by a new sieve. The rapid change device is particularly suitable for installation in an extruder for fabricating rubber hoses for automobile tires, the installation of such rapid change device advantageously being accomplished between the extruder and the injection head.

Abstract: A rail construction for mounting and tensioning an electrically heated screen on and between a pair of longitudinally extending, spaced frame members. The rail preferably is formed as an aluminum extrusion having a relatively large metal mass in cross section. The rail has a modified channel shape in cross section with an upper curved flange, a lower angled flange and an intervening projection. The upper curved flange is enclosed with electrical insulation and is adapted to engage a vertical wall of one of the frame members when mounted thereon. The lower angled flange has a hook shape complementary to a hook shape formed on the edge of the screen cloth. The intervening projection forms a wedge-shaped channel in combination with the lower hook-shaped flange of the rail. The wedge-shaped channel has an angled surface against which a complementary wedge-shaped clamping bar clamps the hooked screen edge.

Abstract: An improved sorting apparatus for sorting sand, rock, gravel and other fragmented material utilizes a wire screen panel having a plurality of sorting zones with the apertures of each zone having a different cross-sectional area. A multiplicity of equally spaced, parallel, serpentinely crimped, longitudinal wires extend from receiving end to discharge end of the panel and are rigidly retained by attachment shrouds at the ends, permitting the longitudinal wires to be tensioned and sagging of the wires avoided by gradually tightening and straightening the longitudinal wires. Mounting means is provided to mount the panel in most commercially available vibrating screen boxes and includes a stationary angle iron mountable at one end of the screen box to retain an attachment shroud at an end of the panel and further includes a plurality of clamping devices adjacent the remaining end of the screen box and engaging an attachment shroud at the remaining end of the panel.

Abstract: A screen tensioning assembly for vibratory, particulate material-screening apparatus of the type including a frame having spaced, parallel, upstanding side panels connected by spaced, horizontal screen support members, and two, extended area apertured screens supported on the support members and extending substantially between the side panels for separating finer from coarser material. An up-turned hook portion is formed at one side of each of the screens. Each of the screens is tensioned by a clamping member having opposite ends with one end normally engaging the respective hook portion and the other end engaging the respective side panel. Each clamping member has a pivot member secured thereto adjacent its other end, extending through an aperture in the respective side panel, and having a portion engaging the respective side panel so that the clamping member may be pivoted upwardly from the respective screen to a stored position thereby to disengage the one end thereof from the respective hook portion.