Abstract: Extruder screw having a feed section, compression section and metering section. The compression section includes two transition portions with a barrier flighted portion disposed therebetween. The screw reduces the power consumption and stock temperature of thermoplastic material.

Abstract: This invention relates to a screw used in an equipment for molding thermoplastic resin, in which a mixing section is provided at a position adjacent a shearing section, and the pitch of a stress relaxation section is preset to the pitch, at which satisfactory kneading can be performed without giving high shearing to the resin. With this screw, even if high-speed extrusion molding is performed, the pressure of resin is not fluctuated, molded parts can avoid lowered material quality and outstanding molded parts can be provided.

Abstract: The present invention relates to a novel extruder screw and method for extruding low melt viscosity polymers which form an anisotropic melt phase. In a preferred embodiment, the method and apparatus according to the present invention employ a high rate of rotational speed of the extruder screw in combination with a relatively low compression ratio and a high volume rate of flow through a compression section in order to effectively extrude the low melt viscosity liquid crystalline polymers. The particular design of the screw is dictated by the unique rheology of the polymers which are difficult to effectively move along the helix of the screw due, in part, to the extremely low viscosity. Each dimension and each relative size of the various sections of the screw must be carefully controlled in order to effectively extrude the unique material.

Abstract: A synthetic resin worm press in which the thread height in an intake zone adjoining a feed opening zone is substantially smaller than the thread height in the feed opening zone, a frustoconical divergent transition piece is provided between the two zones at the core of the worm and longitudinal grooves are formed in the wall of the bore along these zones and are of progressively decreasing depth in the flow direction of the material.

Abstract: A rotor element for use in extrusion and compounding machinery that incorporates means for mixing a low viscosity or immiscible additive with high viscosity base stocks such as polymer melts. The rotor incorporates a combination of one or more helical flights with an array of mixing pins arranged in the cylindrical screw root.

Abstract: A single screw kneading extruder adapted for use with a viscous fluid such as molten plastics and including a first-stage kneading portion (2) and a second-stage kneading portion (4) aligned therewith. The first kneading portion (2) disperses a filler in polymer by a powerful shearing force and has kneading blades (12) on its rotor (10). The filler incorporated into the polymer by the first portion (2) is uniformly blended with and dispersed in the polymer by the second kneading portion (4) having cavities (23), (22) in its rotor (21) and stator (20), respectively.

Abstract: An injection device of an injection molding machine generally comprises a heating cylinder, a screw member disposed therein, and a drive system for driving the screw member. The heating cylinder is provided at its front end with a cylinder head comprising a first portion having an inner frustoconical configuration and being continuous to the front end of the heating cylinder and a second portion being continuous to the first portion and having an inner diameter smaller than that of the heating cylinder. The inner surfaces of the heating cylinder, the first and second portions of the cylinder head are connected linearly smoothly with each other.

Abstract: An extruder of the variety including a body having a cylindrical bore therethrough, and a shaft rotatably supported within the bore. The shaft includes at least a first helical flight means defining a main channel. The shaft is divided along its length into a feed section, an intermediate melt section, and at least one metering section. A portion is included in one of the sections which has a plurality of discrete grooves arranged in a discontinuous helix cut into the main channel. There is preferably a plurality of staggered rows of grooves within the main channel, the axis of each row being substantially parallel to the helical axis of the adjacent first helical flight means. The grooves are adapted to so receive the material forced through the extruder that the average shear force exerted against the material, and thus, the average temperature of the material, is reduced while the output of the material is maintained at a predetermined level.

Abstract: The discharge apparatus comprises an at least four-shaft screw pump having engaging shafts (1,2,3,4) which rotate in opposite directions in pairs. The viscous product to be processed is caught up over a large area and removed by the screws. A double shaft screw pump is connected downstream of the actual collection zone as a pressure build-up zone. The two center screws (2, 3) of the collection zone merge equiaxially into the screw shafts (2a, 3a) of the pressure build-up zone. The collection zone and the pressure build-up zone are combined into one constructional unit. At least one screw shaft is driven. The resulting high viscosity product strands (7) are caught up by the screws in the collection zone and are moved on into the pressure build-up zone. The double shaft screw pump is used for the build up of a high operational pressure and thus provides the prerequisite for the subsequent connection of further procedural stages.

Abstract: A screw- or worm-type degassing extrusion device wherein a pin region is provided to increase throughput of the mixture to be extruded, such increased throughput being maintained and utilized to provide an adequate pressure for, for example, a tool by locating the pin region immediately upstream of the degassing region and by increasing the diameter of the cylinder or barrel of the extrusion device in the degassing and discharge regions compared with its diameter in the pin region.

Abstract: A screw extruder and positive displacement wave pump assembly for plasticating or melting solid plastic material or the like, including an extruder screw member in an elongated cylindrical barrel having an upstream end and a downstream or discharge end, the screw being rotatably housed in portions of the barrel adjacent the upstream end. The screw has a helical thread of plural turns integral with the core of the screw having a minimum clearance to the barrel for feeding the plastic material along the screw from its feed end to its discharge end.

Abstract: An ice making apparatus including a machine for producing and harvesting a flake ice product and transferring said product to an ice extruding chamber in which the product is compressed into a hard column of ice that can be broken into ice chunks or "cubes" of predetermined length and be transported to a remotely located ice storage bin, dispenser or the like.

Abstract: A screw extruder and positive displacement pump assembly for plasticating or melting solid plastic material or the like, including an extruder screw member in an elongated cylindrical barrel having an upstream end and a downstream or discharge end, the screw being rotatably housed in portions of the barrel adjacent the upstream end. The screw has a helical thread of plural turns integral with the core of the screw having a minimum clearance to the barrel for feeding the plastic material along the screw from its feed end to its discharge end. A positive displacement Moineau type pump is located in the barrel near the outlet end having a stator member and a rotor member rotatable therein coupled to and driven by the screw, the stator and rotor members having confronting surfaces of developed helical contours providing helical threads of wide rounded form with a lesser number of threads on the rotor providing a series of pumping pockets which progress longitudinally through the pump section.

Abstract: A rotary extruder contains pump rings positioned at opposite ends of the rotor shaft to collect excess thermoplastic melt forced outwardly to the housing ends and to redirect this excess melt to the feed section of the extruder. Redirection of the melt is accomplished by helical grooves located on the inside surfaces of the pump rings having an axial component directed toward the center of the extruder to provide a conduit for the melt. The melt is also directed by a series of angular grooves positioned circumferentially about the rotor opposite the pump rings which rotationally and axially propel the melt as the extruder rotor rotates. The rotor shaft is supported by bearings at opposite ends of the shaft which are offset from the axial center of the bearing housing.

Abstract: An extruder, including a rotor and a barrel, having mixing or working zones therein in which the material being mixed or worked is transferred layer by layer from upstream grooves in the rotor to input grooves in the barrel, and from output grooves in the barrel, which grooves are interleaved with the input grooves, layer by layer back to downstream grooves in the rotor. The input and output grooves of the barrel are intercommunicated by means of corresponding channels each of which has a selectively radially movable throttling member positioned therein for varying the cross-sectional opening of the channel in which it is positioned and, thus, the amount of shearing action and work performed on the material passing through such channel.

Abstract: An extrusion apparatus having a barrel and a rotatable threaded screw coaxially positioned therein is disclosed. The apparatus includes an upstream inlet section having an opening therein for receiving material to be processed by the apparatus, a compression section downstream of the inlet section, and a mixing or plasticizing section downstream of the compression section. The interior surface of the barrel is provided with an undercut therein which intercommunicates the feed opening with the compression section and has a portion thereof which extends downstream in the compression section about the interior surface of the barrel with a continuously decreasing cross-sectional area. The undercut may be formed in a cylindrical insert carried within the barrel and, in an alternate embodiment, a second undercut cylindrical insert positioned about the first insert and rotatable relative thereto may be employed to vary the cross-sectional area of the undercut.

Abstract: An apparatus and method for extracting water from rubber is provided. The rubber is screw conveyed in a twin screw extruder and alternately compressed between the forward side of the screw conveying threads, the inner extruder chamber wall and the wedge-shaped screw shaft. Water is squeezed out of the compressed rubber particles and drained off. The extruder chamber wall preferably has longitudinal grooves to impede the revolving movement of the rubber particles and to further squeeze the water from the rubber particles.

Abstract: A juice extractor device comprises a juice extractor body having a horizontally disposed slightly conical internal bore and a rotary body mounted in said bore. The juice extractor body includes a material inlet port on the upper side of the base end of the extractor body, a juice discharge port along the lower side of the extractor body, and a residuum discharge port on the upper side of the outer end of the body, and each port communicates with the bore. The juice discharge port includes a filter whose inner surface has a curvature equal to that of the bore surface. The rotary body is disposed adjacent all the ports and comprises an outer circumferential surface which has a spiral compressing portion confronting the two discharge ports and a spiral blade confronting the inlet port. The spiral compressing portion comprises a spiral wing and a valley therealong. The spiral blade, which is continuous with the spiral wing, also comprises a valley therealong.

Abstract: The advantages of a twin-screw extruder, especially the good plasticizing and homogenizing effect, are to be retained in the present invention with a simultaneous, above-average degassing output of the extruder. This object is achieved by dividing the twin-screw extruder into two stages (a) the plasticizing and homogenizing stage with a high screw torque and (b) the degassing and discharging stage in which a large, free degassing volume is achieved by a reduction in the screw core, by an enlargement of the screw housing and by adapting the screw diameter to the respective housing diameters in the degassing and discharging stage.

Abstract: A double-worm press, especially an extrusion or plastifying press for thermoplastic materials and particularly high viscosity thermoplastics, has generally conical worms, at least the discharge zones of which are formed so that the material is treated generally adiabatically therein. For this purpose, the end of the discharge zone has a depth of the worm flight which is between 24 and 33% of the worm diameter, preferably between 26 and 30%, with the ratio of the depth of the flight (or height) to the diameter of the worm increasing progressively away from the discharge end, counter to the direction of feed of the material.

Abstract: Extruders are widely used to transform solid plastic materials into molten plastic materials. Because of the low thermal conductivity of plastic materials and the inefficient mixing of the plastic materials inside an extruder, the heat is not evenly distributed in the material being processed and some portion of the material emerges from the extruder with excessive heat. This invention discloses a new screw with a novel mixing section which promotes mixing of the hot, molten material with the cold, unmolten material inside the screw channel by its unique geometry, thereby improving the heat transfer from the hot, molten material to the cold, unmolten material and increasing the energy efficiency of the extruder.

Abstract: This invention pertains to a field of the art for producing crude oil from rice bran, and it relates to a pretreatment method for extracting crude oil from rice bran and an apparatus used therefor.The object of this invention is to obtain an extremely high-quality and light-colored crude oil from rice bran while eliminating any risk of environmental pollution in the pretreatment process for the extraction. In order to accomplish this object, as the pretreatment for extracting crude oil from rice bran, said rice bran is compressed in a screw extruder to break the cells in said rice bran and mold it into a form suited for the extraction of crude oil.

Abstract: An apparatus for continuous extrusion of a material including a hollow barrel with inner liner having a cylindrical chamber portion and an outwardly divergent, coaxial frusto-conical outlet chamber portion adjacent thereto so that reverse pressure developed by extrusion of the material results in sealing engagement of the frusto-conical screw and barrel portions thereby effectively preventing regurgitation of the material. A fluted screw is rotatably positioned coaxially within the barrel and liner, and has both cylindrical and outwardly divergent outer thread surface portions conforming to the inner surface of the cylindrical and the frusto-conical chamber portions, respectively, of the barrel and liner. Rotation of the screw forces the material to flow axially through the barrel along the threads of the screw toward the outlet chamber portion and through an extrusion die.

Abstract: An insulating coating of extruded polymer material is formed around a moving conductor wire; the extruder includes a decompression zone effective to arrest shear degradation of the polymer such that the melt index of the insulating polymer on the insulated wire is not more than 50% of the melt index of the solid, particulate polymer material before extrusion; the extruder includes valve means and intense mixing means which ensure that the polymer melts in a controlled manner whereby a uniform extrudate is formed.

Abstract: An extruder for oilseed products, grain mash, and other materials includes an elongated screw rotatably disposed in a bore formed in a tubular housing. The screw is characterized by a plurality of separate threads of progressively decreasing pitch toward a discharge end of the screw. The separate threads are spaced apart and thread portions of constant pitch include gaps to provide clearance for radially inwardly projecting pins disposed in the housing and projecting into the material flow path for mixing the material to prevent solidification thereof and clogging of the extruder. The screw shaft includes spaced apart annular collars which comprise backflow dams for the material being conveyed through the extruder. The tubular extruder housing is of modular construction and is adapted to be used with various combinations of tubular inserts and a plurality of stacked annular rings forming the extruder bore.

Abstract: A high output extruder screw which produces throughputs at lower temperatures and lower specific energy input. The screw has a feed section, a first short transition section, a first metering section, a second short transition section and a second metering section wherein the screw diameter increases from the feed section to the second metering section. There is also provided a method for extruding specific ethylene polymers.

Abstract: An automatic dough-processing apparatus which includes a vertical assembly constituted by a tubular processing chamber whose upper end communicates with a metering tube of enlarged diameter to which flour is supplied. Coaxially mounted within the assembly is a rotating shaft having a main screw section of uniform diameter operating within the chamber and a conical valve section operating within the tube. Slidable within the metering tube is a ring which surrounds the valve section to define an annular valve orifice, the ring being axially shiftable by an adjusting element to set the size of the orifice. The flour admitted into the chamber by the metering tube is hurled by the main screw section against the inner wall of the chamber to create a thin flour film thereon which is bombarded by the solution to form a paste, the paste being then kneaded.

Abstract: Method and apparatus are disclosed for the low energy melting, extrusion and pumping of material comprising feeding, metering, melting and mixing of such materials in an extruder having a melter screw and subsequently passing the resultant extrudate, through breaker plate and adapter means, to and through a rotary gear pump and, in turn, to a die member.

Abstract: The present invention provides an apparatus for texturizing protein products; the apparatus includes a screw conveyor through which a protein dough containing a heat coagulable protein is passed with the conveyor having an internal conveying section changing in configuration such that the dough is stretched during passage through the conveyor, while being heated to a temperature above the heat coagulation temperature of the protein to provide a meat-like fiber structure wherein the fibers are aligned.

Abstract: A continuous foam production system is disclosed wherein a molten thermoplastic resin is mixed with volatile blowing agent at elevated pressure to form an extrusion mass. A helical screw extruder means is adapted to extrude the molten resin with volatile blowing agent into a low pressure foaming zone to form a foam sheet, tube or other shape. An improved fluid handling system includes storage means for holding at least one of a plurality of disparate volatile liquids under pressure sufficient to maintain a normally gaseous blowing agent in liquified state and cooling means for receiving a pressurized first stream of liquified thermally-gaseous blowing agent and cooling below its autogenous temperature. A pump operatively connected between the cooling means and extruder means increases pressure of the first stream higher than the elevated pressure of the extruder, where it may be combined with a pressurized stream of second liquid blowing agent.

Abstract: A novel extruder screw having at least three segments wherein the pitch remains constant in each segment and changes abruptly from one segment to the following segment and wherein the pitch ratio divided by the depth ratio is greater than 2/3.

Abstract: Method and apparatus in which a selected coating is applied to specific surfaces within a plasticating extruder to change the coefficient of friction between the solids being conveyed in the extruder and the specific surfaces in such a way as to improve solids conveying and thereby increase the production effectiveness of the extruder.

Abstract: Apparatus for kneading compounded resinous material includes a cylinder within which there is sequentially arranged a preheating feed zone, a plasticizing kneading zone, a degassing zone and a measuring zone. A screw is rotatably positioned within the cylinder and extends through all of the afore-mentioned zones. The portion of the screw within the plasticizing kneading zone has a plurality of continuous helical flights each of which is given a front wall facing in the direction of screw rotation substantially perpendicular thereto. A rear portion of each flight defines a groove with the next adjacent flight such that the diameter of the screw between flights progressively decreases in the direction opposite to screw rotation. A plurality of axially extending recesses are formed on the interior surface of the cylinder which extend at least through the preheating feed zone and the plasticizing kneading zone.

Abstract: Methods and apparatus for marbleizing molded parts produced by screw extruder machines. Liquid colorant is advantageously injected at a comparatively high pressure into a melt containing portion of the machine between the screw and its housing, where the melt is either completely molten or more than fifty percent molten.

Abstract: An injection molding apparatus is disclosed which includes a screw having a multichannel wave screw section. In the wave screw section, a helical passage defined by a radially extending helical screw flight is divided into a pair of flow channels by a radially extending helical barrier. The helical barrier is radially shorter than the helical conveying flight and the effective outer width thereof is axially narrower than the helical conveying flight. Each flow channel is provided with an undulating base surface that defines a plurality of wave cycles. The base surface varies in a radial direction between a valley portion and a crest portion for the wave cycle and a wave cycle is defined as extending between consecutive crest portions. The crest portions of one flow channel are helically displaced from the crest portions of the adjacent flow channel.

Abstract: A device for feeding or pressing plastics material to an extruder includes a conically shaped housing with its apex directed downwardly and with a similarly conically shaped feeding member within the housing. The outer surface of the feeding member is parallel to and spaced inwardly from the inner surface of the housing. A screw blade is secured to and extends helically around the outer surface of the feed member. A partition wall divides the interior of the housing into an upper storage chamber and a lower material conveying chamber. The partition wall is constructed to provide variable openings for admitting material from the storage chamber into the conveying chamber.

Abstract: An extruder having a multichannel wave screw is disclosed wherein at least one portion of the screw is provided with a helical passage that is divided into a pair of parallel flow channels. The helical passage is defined by a helical conveying land which extends radially outwardly to a first diameter from the screw root, which defines the bottom surface of the helical passage. To divide the helical passage into the pair of flow channels, a helical barrier land extends radially outwardly to a second diameter which is less than the first diameter. Each flow channel is further characterized by the existence of an undulating screw root which defines a plurality of waves, each with a crest and a valley. The crests of one flow channel are helically displaced relative to the crests of the adjacent flow channel.

Abstract: An injection molding screw for use in processing heat sensitive polymeric materials and a process for plasticating such materials. The screw has an inlet end, a discharge end, means for mounting a backflow valve on the discharge end, and at least one section which applies high shear and high compression to the polymeric material and controls the material flow rate. A flighted screw section is disposed between the high shear and high compression section and the discharge end; that screw section includes means for decompressing the polymeric material and pumping it to the discharge end of the screw in the decompressed state at a rate at least equal to the pumping rate of the zone of high shear and high compression.

Abstract: An apparatus for the mixing of materials such as synthetic polymers and their additives. The apparatus comprises a casing which surrounds a cylindrical rotor. A series of groove rings are axially arranged in succession in the casing and have end surfaces placing the rings in abutting axial engagement with one another. These end surfaces of each groove ring may be integral therewith or may be provided by separate spacer rings. The grooves formed on the peripheral working surfaces of the groove rings are circumferentially separated by shearing lands and are limited in an axial direction by said end surfaces, said shearing lands and end surfaces defining said grooves as a series of individual closed chambers.

Abstract: An injection molding screw for use in processing heat sensitive polymeric materials and a process for plasticating such materials. The screw has an inlet end, a discharge end, means for mounting a backflow valve on the discharge end, and at least one section which applies high shear and high compression to the polymeric material and controls the material flow rate. A flighted screw section is disposed between the high shear and high compression section and the discharge end; that screw section includes means for decompressing the polymeric material and pumping it to the discharge end of the screw in the decompressed state at a rate at least equal to the pumping rate of the zone of high shear and high compression.

Abstract: A method of and apparatus for melting a thermoplastic material in order to obtain an at least nearly homogeneous molten mass, according to which a granular or similar material is melted while it is being transported e.g. by a screw conveyor through a space between a housing of circular cross section and a body rotating in the housing. The transfer of heat to the granular or similar material takes place over at least an axial section of the space between the above mentioned housing and the rotatable body. This space is divided into alternating inlet and discharge channels by first ridges fixedly connected to the rotating body over the above mentioned distance and extending along the inside surface of the housing so as to at least nearly block the passage of molten material, and by second ridges respectively arranged between the first ridges and extending at least substantially parallel to the first ridges while being fixedly connected to the rotating body.

Abstract: In a resin moulding screw provided with helical flight and valley, the bottom surface of valley is divided into a plurality of portions along a dividing line, and the divided portions are alternately displaced in the radial direction to form wavy contours. Barriers are provided to cross the dividing line to form dams which prevent intercommunication of the valleys at the bottom of the screw groove to prevent decrease of the thrust pressure along the flight for efficiently blending and melting solid and molten resins.

Abstract: This invention provides in a continuously operating device having a mixing section comprising opposite-handed helical threads in each of the two relatively rotatable components which threads vary in cross-sectional area in complementary fashion so as to produce a layer-by-layer material transfer and shear working between the said components, that the said opposite handed helical threads in said mixing section complement one another substantially also in respect to their helix-angles to the extent that if one helix angle is between 0.degree.and 45.degree. the other is between 45.degree. and 90.degree., to bring about, viewed with respect to the shear-plane-area, a subdivision sufficient for the mixing and compounding requirement.

Abstract: Thermoplastic granules mixed with a blowing agent are processed in a barrel unit which encloses a rotating screw which mixes, works and plasticizes the mixture so that at the leading end of the barrel it is in a molten condition suitable for extrusion or injection molding. The screw has two compression stages with an intermediate decompression stage therebetween. At a location corresponding to the decompression stage of the screw the barrel has a vent therein which permits the escape of moisture vapors and other unwanted volatiles in the mixture. At the vent zone the forward faces of the screw flights are undercut to minimize the discharge of mixture through the vent.

Abstract: Methods and apparatus for marbleizing molded parts produced by screw extruder machines. Liquid colorant is advantageously injected at a comparatively high pressure into a melt containing portion of the machine between the screw and its housing, where the melt is either completely molten or more than fifty percent molten.

Abstract: A method and apparatus are provided for the extrusion of a thermoplastic material in modified form in which the thermoplastic material is introduced into the barrel of a screw extruder, and is heated and forced through the barrel: the material is passed through valve means which together with the temperature of the material is effective to produce a melt transition in the material at a predetermined point and to thoroughly mix the material; subsequently, the material is forced into a low pressure zone in the barrel where a modifying agent is introduced into the material; the resultant mass is forced out of the low pressure zone, and is passed through a mixing means effective to intensify the dispersion of the modifying agent in the mass, the mass is extruded and the extruded material collected.

Abstract: In accordance with the present invention an extruder screw having a helical conveying land is provided with a helical barrier land therewithin to form a pair of parallel helical flow channels. Each flow channel includes repeating wave cycles. Each wave cycle is of varying depth, having alternating wave crests and valleys. The wave cycles of the adjacent channels are helically offset so that a wave crest of one channel lies opposite a valley in the adjacent channel. The barrier land is undercut in a manner which facilitates the flow of melt thereacross from one channel to the other, while restricting the flow thereacross of unmelted solids. Solids thus tend to pass through a restriction formed by the wave crest while the melt travels across the barrier flight into the adjacent channel, thereby minimizing the formation of pressure pulses in the extrudate flow. The clearance above the barrier flight is small, and the width of the barrier flight is very narrow so as to impart little energy input i.e.

Abstract: A cohesive, non-flowable, plastic mass which is difficult to handle in bulk form is subjected to removal from a container and guided flow into a screw conveyor, compression in the conveyor, and controlled heat input and withdrawal while transported by the conveyor to facilitate ultimate extrusion.

Abstract: A method and apparatus for feeding an additive, such as glass fibers, fillers, etc., to a plastic resin in an extruder is disclosed. The additive is fed by means of a screw type feeder into the barrel of a plastics extruder or reciprocating screw plastifier at a location where the resin is molten and the resin pressure is low.

Abstract: A plasticizing and melting apparatus for granular synthetic plastic material has a heatable cylinder one end of which has an inlet opening for reception of granular material from an adjustable feeding unit which includes a shaker. The cylinder surrounds a rotary feed screw having a material advancing section in the region of the inlet opening, a first material densifying section immediately downstream of the advancing section, a collar which defines with the cylinder a narrow annular shearing gap immediately downstream of the first densifying section, a pressure relaxing section immediately downstream of the collar, and a second densifying section immediately downstream of the pressure relaxing section. The cylinder has one or more gas evacuating apertures which connect the interior of the cylinder with the atmosphere in the region surrounding the pressure relaxing section.