Abstract: This invention relates to a plasticating screw suitable for use in an injection molding machine or an extruder. In the plasticating screw which is rotatable within a cylinder and has a mixing head (7) with plural groove portions (7a,7b) formed therein, recesses (2,3) in the shape of steps or slopes are formed on an outer peripheral surface (7d) of the mixing head (7) other than the groove portions (7a,7b) so that the recesses are in communication with the groove portions (7a,7b) located forward thereof as viewed in a direction of rotation.

Abstract: An extruder assembly has a gear box drivable by a motor, an output shaft having a main portion extending through the gear box and rotatable by operation of the motor and gear box, and an extruder housing located forwardly of the gear box. The output shaft has a further portion extending forwardly from the main portion and passing into the extruder housing and having a screw configuration therein for feeding plastic material through the housing when the output shaft is rotated. The main portion of the output shaft is axially slidable in the gear box, and the forwardly extending portion has a diameter not greater than the diameter of the main portion whereby the output shaft can be withdrawn from the housing and the gear box by rearward movement therethrough. A retainer is operable to retain the output shaft in an operative position for rotation to feed plastic material through the housing and also to permit the output shaft to be withdrawn by rearward movement when desired.

Abstract: An extruder screw having at least one raised part forming a thread projecg on a core intended to be rotatably mounted inside an extruder roll in which the raised part includes a crown wall and side walls intersecting with the crown wall, the intersections between each of the side walls and the crown wall forming edges intended to cut the material, the crown wall of said raised part being provided with a coating of at least two materials of different hardnesses placed side by side on the crown wall.

Abstract: A screw extruder (10) having a barrel (18) which has a bore (26) defining an inner surface (44) and one or more extruder screws (28), positioned within the bore (26). The extruder screw or screws (28) include a central shaft (34) and one or more screw flights (30). The extruder screw or screws (28) farther including one or more dispersive mixing elements (204), (234), (308), (406), (508), (558), which interact with the inner surface of the barrel (44) to form one or more progressively narrowing passages (46) through which material is forced into multiple regions of high elongational and shear stress (480, (120), (214), (310), (410), (510), (564).A second preferred embodiment is a screw extruder (10) having a barrel (18) having a bore (26) defining an inner surface (44) and one or more extruder screws (600), (701), positioned within the bore (26).

Abstract: A multichannel wave screw with a slush channel barrier section adapted to provide a consistent mixture of 50% solids and 50% melt to both channels of the double wave metering section. The screw includes a barrier flight having a relatively large initial clearance which allows solids to enter the newly formed slush channel. The barrier flight gradually decreases in clearance to a final barrier flight clearance which allows some dispersed solids to enter the slush channel. At the terminal end of the barrier section, the barrier flight abruptly increases its pitch, thereby abruptly narrowing the solids channel and therefore forcing solid material over the barrier flight and into the slush channel. In this manner, a uniform mixture of solid and melt is provided to the multi-channel wave metering section.

Abstract: A single flighted multi-screw conveying bushing that has only one helical screw element extending the length of the bushing. The bushing has a cross-section shape that has a segmented circular base and a lobe extending from the base. The lobe has a truncated crest that is sized to have a circumferential angle of from 15.degree. to 30.degree. and preferably from 22.degree. to 24.degree.. Also, a twin screw extruder having a pair of side by side drive shafts with at least two of the single flighted screw bushings mounted end to end on each shaft.

Abstract: A method for producing a high solids aqueous solution of poly(vinyl alcohol) in which substantially dry poly(vinyl alcohol) is first fed into a specially designed single screw extruder. Heated water is introduced through a separate entry port downstream of the feed end of the extruder. A temperature of 38 to 121.degree. C. and a back pressure of at least 20,786 kPa are applied to the extruder. The mixture of poly(vinyl alcohol) and water is conveyed through transition and metering sections of the single screw extruder to dispersive and distributive mixing sections to produce a high solids poly(vinyl alcohol) solution which is substantially free of gels. The high solids poly(vinyl alcohol) solution can be used directly in the production of products such as fibers and sheets.

Abstract: An extruder screw, includes a head portion having a front end and having formed therein a temperature-control bore and a counterbore extending the bore to the front end for supply and drainage of a fluid. A locking screw has a screw thread, with a first section of the screw thread received in the bore and a second section of the screw thread extending in the counterbore and projecting out of the head portion. The extruder screw further includes a screw tip which threadably engages the second section of the screw thread to close off the extruder screw, and a sealing member which is received in a counterbore of the head portion, wherein the locking screw is so configured as to apply a substantial force against the sealing member when engaging the locking screw into the bore, to thereby effectively seal the bore.

Abstract: Polyvinyl alcohol is processed into fiber or pellets for further processing, or directly into water-soluble film, in a screw-and-barrel extruder, which has a slow temperature rise and a mild kneading action achieved by a non-stick coating applied to the screw.

Abstract: An apparatus for processing feed stock into a thixotropic state. The apparatus includes a barrel with first, second and nozzle sections. The first, second and nozzle sections are connected together and include surfaces that cooperatively defining a central passageway through the barrel. The first section is constructed of a first material, the second end section is constructed of a second material and the nozzle is constructed of a third material. The first material exhibits a greater resistance to thermal fatigue and thermal shock than the second material while the nozzle section includes a bushing which inhibits heat transfer to the die, precluding excessive molding pressures and cycle times. The apparatus also includes a preheater for preheating the feed stock before entry into the barrel, a thermal gradient monitoring system, a novel robust nozzle construction, and a two-stage embodiment of the apparatus.

Abstract: An extruder screw for use in a barrel of an extruder for forwarding thermoplastic polymer from a first end to a second end of the extruder. The extruder comprises a transition section and at least one flight extending substantially along the length of the screw. A dam is positioned at the point where the rapid melting of the solids starts to slow down and the rate of solid bed width decrease approaches zero. The dam provides the screw with a high output of extrudate and close control of the residence time of polymer particles as they are transported through the screw, resulting in an extrudate which is uniformly melted and which is substantially free of degradation products and/or entrapped air.

Abstract: In a screw-type extrusion machine comprising a composite casing which comprises casing sections fitted together in a longitudinal direction, the casing sections being tightly tautened relative to each other by a plurality of tie rods which extend parallel to each other in the longitudinal direction of the casing on the outside thereof, it is provided with a view to avoiding any over-stressing of the tie rods in the hot condition and to avoiding any leakage between the casing sections in the case of low temperatures and non-uniform temperature distribution, that the tie rods are loaded in the longitudinal direction by a pre-stressed spring system.

Abstract: A worm or screw conveyor for the thermal treatment of a bulk containing thermoplastics and which has an elongated housing along which the bulk material is conveyed by a worm or screw. The worm or screw has a certain peripheral diameter and is rotatable about the worm axis to displace the bulk material therealong and an infrared heater is located in the housing centrally of the peripheral diameter for directly exposing bulk material in the housing to infrared radiant energy to heat the bulk material.

Abstract: A single screw extruder of the type having a drive shaft coupled to the screw for rotational movement wherein the improvement comprises coupling the drive shaft to one end of the screw through a plurality of splines on the screw.

Abstract: An apparatus for processing feed stock into a thixotropic state. The apparatus includes a barrel with first, second and nozzle sections. The first, second and nozzle sections are connected together and include surfaces that cooperatively defining a central passageway through the barrel. The first section is constructed of a first material, the second end section is constructed of a second material and the nozzle is constructed of a third material. The first material exhibits a greater resistance to thermal fatigue and thermal shock than the second material while the nozzle section includes a bushing which inhibits heat transfer to the die, precluding excessive molding pressures and cycle times. The apparatus also includes a preheater for preheating the feed stock before entry into the barrel, a thermal gradient monitoring system, a novel robust nozzle construction, and a two-stage embodiment of the apparatus.

Abstract: A mixing apparatus suitable for mixing and conveying solid, particulate, polymeric materials, comprising a barrel that can be heated and cooled, at least two co-rotatable, self-wiping extruder screws located within the bore of the barrel, the screws being connected through a laterally flexible coupling to a drive means which can reverse the direction of rotation of the screws upon the occurrence of a predetermined event. The apparatus also comprises a closeable feed port and a closeable discharge port, both of which can be made gas-tight, the shafts of the screws being provided with seals capable of withstanding elevated gas pressures inside the barrel.

Abstract: A screw extruder (10), including a barrel (18) having a bore (26) which defines an inner surface (24). At least one extruder screw (28) is positioned within the bore (26), each screw (28) further including a central shaft (34) and at least one screw flight (30). Each screw flight (30) further includes a front pushing face (36) and a rear face (38). The profile (40) of each front pushing face (36) acts with the inner surface (24) of the barrel (18) to form a progressively narrowing passage (46) through which material is forced into multiple regions of high elongational and shear stress (48) which act to break down agglomerates of material and thus dispersively mix the material.Also presented is a screw extruder (100) having a single screw (28) which includes dispersion disks (102) which are rotationally offset from one another and whose design is not constrained by interaction with a second disk, which provides improved distributive and dispersive mixing.

Abstract: An extruder for melting plastic granules which is designed as a two-stage system in an integrated structural unit with an extruder chamber having an extruder screw in a heatable housing, as well as with a drying chamber having a heated conveying screw with displacement elements which dry the plastic granules and axially convey them to the extruder chamber without compression. In a preferred embodiment, the conveying screw has a larger diameter than the extruder screw, and displacement elements of greater depth than the extruder screw.

Abstract: Angled scraper blades provided on the end of a screw shaft of an extruder provide thrust for propelling polymer toward the die opening of the extruder. The scraper blades help prevent trapping of polymer between the shaft and the die plate of the extruder, which trapping can lead to scorching, burning or break down of the polymer.

Abstract: An extruder for plasticating and extruding an extrudate, and an extrusion screw used with the extruder form the subject of this invention. The extruder screw includes an elongated root body and a thread portion helically wound about the root body and extending along the length. The screw having a low compression ratio, flight with a reduced helical angle, and a conical, tapered front end section where at least one-half flight of the thread has a pitch associated therewith which is different from the pitch of the remainder of the thread and where the diameter is less than the diameter of the remainder of the root body.

Abstract: An extruder device includes a rotor rotatably received in a housing and a tube secured to the rotor and having a helical screw formed in the outer portion. A screw member is engaged in the bore of the rotor and secured in the tube and rotated in concert with the tube and the rotor. The material to be extruded is supplied onto the tube and moved by the helical screw and then by the screw member. The helical screw includes a pitch greater than that of the screw member for allowing the helical screw of the tube to squeeze the material.

Abstract: A device to mix and extrude various ingredients including pastas, pastries, baked goods, hors d'oeuvres, and cookies. The device includes novel measuring, mixing and extrusion arrangements including: an automatic measuring cup; a way to continuously mix and extrude ingredients without intervening cleanings; a mixing and extrusion feed for handling different consistencies of ingredients; an integrated automatic cutter; motor cooling and extruded ingredient drying; as well as various safety devices.

Abstract: A kneader with a vent function, including a kneading extruder, which permits the continuous viscous flow of material to be kneaded even at a high speed rotation to prevent the generation of cuttings and exhibiting sufficient venting capability. The kneader includes a barrel having kneading chambers defined therein, a rotor rotatably inserted into the kneading chambers, and having a feed portion on an outer peripheral surface thereof. A vent port is in communication with the kneading chamber of the barrel at a position around the feed portion. The feed portion in a vent zone includes a screw tip having a material feed surface with an outwardly curved surface in section.

Abstract: This invention relates to extruders of the type which employ single screws that use chaotic mixing to generate substantially better distributive mixing. Such structures of this type, generally, stretch and fold material lines repeatedly such that interfacial areas between material elements increase exponentially and heat/mass transfers are greatly enhanced.

Abstract: The extruder screw drive has a first and a second motor, a screw mechanism connected to the first motor and to the extruder screw for translating it in the extrusion cylinder, and a slide mechanism connected to the second motor and to the extruder screw for rotating it in the extrusion cylinder. The screw mechanism and the slide mechanism are coaxial and partially fit into one another to provide an axially compact arrangement. The motors can be hollow shaft electric motors axially aligned together, and pressure regulated hydraulic axial force can be added to the extruder screw during plasticating as it retracts due to increased volume of plastic at an output end of the extrusion cylinder.

Abstract: A method for forming an article from recyclable plastic materials includes progressively heating thermoplastic solid particles simultaneously with mixing, melting and conveying the particles, prior to delivery of molten material to an extruder. The process is particularly suitable for the continuous extrusion of elongated members having a plurality of internal wall surfaces defining elongated cavities within the member. The apparatus embodying the present invention includes a heated mixer-conveyor that simultaneously heats, melts, mixes and conveys thermoplastic material from an inlet port at which the material is received in solid particulate form, to a discharge port at which the material is in a substantially liquid state. A die particularly adapted for the continuous extrusion of an elongated member having internal walls shaped by surfaces within the die cavity is also disclosed.

Abstract: An interchangeable injection screw for use in an injection molding machine is disclosed. It comprises: (a) an interchangeable feeding section, an interchangeable compression-and-melting section, an interchangeable metering-and-mixing section, and an interchangeable screw head, wherein the interchangeable feeding section, the interchangeable compression-and-melting section, the interchangeable metering-and-mixing section and the interchangeable screw head can severed from each other; (b) a splined shalt integrally formed with the interchangeable feeding section and extending in front thereof so as to sleevedly receive, in order from the feeding section, the compression-and-melting section and the interchangeable metering-and-mixing section; and (c) a screw means for affixing the interchangeable screw head to the splined shalt so as to form a complete injection screw.

Abstract: A method and mixer for mixing peat and sludge into a homogenous mass, in which method the peat and sludge is mixed by pressurizing the pre-mixed mass for some time, when the sludge is absorbed by and bound in the peat. The mixer in accordance with the invention includes a silo (1) and a screw conveyor (4) located beneath it, from which the mass is squeezed out through a nozzle (10).

Abstract: Assembly for the continuous plasticising and filtration of materials. The materials include polymers in the pasty, viscous, or molten state, visco-elastic products and proteoleaginous products. The assembly includes two modules, a plasticising module and a degassing and filtration module. A stator accommodates a floating screw and, in succession, a feed zone receiving the material to be plasticised, a homogenization zone, a degassing zone, a zone for the filtration of the non-molten material, and a zone for the outlet of the plasticised material. The portions of the stator which correspond to the various zones are provided with temperature regulating means, formed of a condenser, a heating device, and an annular chamber.

Abstract: An extruder in which the joint between the downstream, forward end portion of a cylinder and a gear pump is always kept tight, so that molten resin material is prevented from leaking out. As the main discharge port of a diverter valve is prevented from shifting from the inhalation port of the gear pump at the joint therebetween, the flow passage at the joint is always smooth without a spot where the molten resin material collects. The quality of resin products thus becomes stable.

Abstract: A screw of a screw-in-line type plasticizing device of an injection molding machine has a cylindrical main part and a spiral screw flight on the main part. A portion of the screw flight of the screw facing a resin supply port has a parallelogrammic axial sectional shape which is inclined towards the discharge end of the screw.

Abstract: In a thermoplastic material extrusion line having a melt extruder, a gear pump, and a die aligned with one another, the gear pump is supported on a hinged articulable arm for swinging movement into and out of operative disposition in alignment with the extruder to simplify realignment of the gear pump with the extruder and the die whenever it becomes necessary to remove the gear pump from the line for maintenance or service.

Abstract: A mixer of the type comprising an axle (2) such as a screw rotatably mounted within a trough (1) is characterized in that the rotatable axle (2) has at its periphery at least one opening comprising an injection point (21) or distribution point of at least one of the constituents of the mixture. The mixer is useful in the production of foundry molds.

Abstract: The invention is directed to a method and an arrangement for continuously producing a rubber base compound and a rubber end compound in a single stage for vehicle tires, drive belts, conveyor belts as well as for industrial rubber products. The rubber base compound and the rubber end compound are produced continuously in one and the same mixing arrangement which includes a twin-screw extruder.

Abstract: A plasticizing apparatus (10) including a barrel (12) having a bore (14) therethrough. An auger (24) and a rotor (30) are positioned in the bore, each extending from opposed ends (16, 18) of the barrel (12) and having ends (26, 34) that are substantially flush. The auger (24) conveys particulate plastic material along the bore (14), the plastic being frictionally melted before passing the auger discharge end (26). The rotor (30) is provided to uniformly heat the melted plastic. Auger (24) and rotor (30) each are associated with independent means for rotating (28, 32) and means for controlling the speed of rotation (50, 52). The speed of rotation of the auger (24) controls the flow rate of plastic through the bore, and the speed of rotation of the rotor (30) controls the temperature of the melted plastic.

Abstract: A machine for processing solid and viscous plastic materials includes a screw element having a shearing flight and a scraping flight. Upon rotation of the screw, the shearing flight shears the plastic material and the scraping flight guides the material to the shearing flight. Preferably, the screw includes a plurality of threads which extend from one end of the screw to the other, and which include a plurality of shearing and scraping flights.

Abstract: An extruder for processing plastic material has a housing with a longitudinal bore in which an extruder screw is coaxially fitted for rotation around an axis of the screw to advance plastic material through the bore by threads on the screw. A plurality of throttling plungers are slidably supported in rectangular slots in the housing perpendicular to the axis of the screw. The throttling plungers define an inner throttling surface facing an outer thread-free region of the screw to form an annular throttle gap therewith. In order to avoid uncontrolled changes in the throttling system, the throttling surfaces are not concentric with the outer surface of the screw, so that the throttle gap has a width which varies progressively and symmetrically around the screw.

Abstract: A dough mixer has a dough material feeding inlet and a dough discharging outlet at upper and lower portions of a housing, in which a mixing member is disposed. The dough mixer further includes at least one metal shutter member for opening and closing the dough material feeding inlet and the dough discharging outlet, and a guide rail member contacting of the at least one of metal shutter member for guiding motion of the shutter member through an established motion path, the guide rail member being formed of a synthetic resin. The at least one shutter member for removing a dough material in the motion path of the shutter expels compressed air at its tip.

Abstract: An arrangement for mixing and/or kneading of viscous, plastic, powder or grain materials, comprises a housing provided with a housing opening, a screw shaft driveably arranged in the housing opening and having a torque transmitting shaft and a plurality of screw elements arranged one behind the other on the shaft, a wedge connecting the screw elements with the shaft and having a substantially rectangular cross-section with two long sides and two short sides.

Abstract: An extrusion apparatus 10 for extruding thermoplastic materials comprises a hollow cylindrical barrel 12 having a preferably smooth inner cylindrical wall 14. An extrusion screw 16 is mounted for rotation about an axis 18 within hollow barrel 12. The extrusion screw 16 has a major diameter, a minor diameter defining a minor circumferential surface (MCS) of the screw 16, and material pushing threads that are spaced axially and have a normal height `h` extending outwardly from the MCS of the screw into rotatable contact with the inner cylindrical wall 14 of the barrel 12.

Abstract: Method and apparatus for the electromagnetic dynamic plasticating of polymer materials includes a magnetic moving body which is supported both axially and radially by a magnetic levitation gap. The magnetic body is rotated in non-steady state vibration within an electromagnetic winding and cooperates with a stationary body to form a processing space for the polymer material.

Abstract: An apparatus for manufacturing an optical disk substrate having a foreign-substances index of not more than 1.times.10.sup.5 .mu.m.sup.2 /g, an optical information-storage medium wherein the substrate has an information-recording layer, includes a cylinder with a liner and a screw coated with TiC and TiN.

Abstract: A dynamic mixing system and method intensively mixes thermoplastic melt with other ingredients and entrains gas as a blowing agent in a thermoplastic melt so as to provide a foamed thermoplastic extrudate. The dynamic mixing system includes a plurality of mixing balls disposed circumferentially about the surface of a cylindrically shaped spindle which is rotatably disposed within a barrel, such that upon rotation of the spindle the mixing balls rotate in a planetary manner so as to intensively mix a flow of thermoplastic melt, for example, to entrain a blowing agent in the melt.

Abstract: Aqueous non-self-emulsifying polymer dispersions having small particles and a long shelf life and based on highly viscous reaction resins are prepared without the addition of solvents, by means of an intensively dispersing screw apparatus, by a continuous process in which the preparation of the polymer dispersion is carried out in an intensive shear zone of the screw apparatus, the water/reaction resin ratio in this intensive shear zone corresponding to the phase inversion point or being close to it, and the specific energy supply is 0.01-0.15 kWh/kg, the residence time is 0.1-60 sec and the shear gradient is 2,000-20,000 sec.sup.-1.

Abstract: A fast cycle plasticator/injector unit for plastic molding machines having a screw type plasticating extruder for feeding thermoplastic material through a sealed fluid flow path to an accumulator which periodically feeds the thermoplastic material through a sealed fluid flow path to an injector that comprises a cylinder with an inlet and an outlet port and a powered piston valve element disposed for reciprocating axial and rotary motion within said cylinder and having a fluid flow channel along a portion of its length in cooperative structural relationship with said inlet port to provide an open fluid flow channel between the inlet port and the charge chamber of said cylinder when the piston is in a first rotational orientation and to block fluid flow from the inlet port to the cylinder when the piston is in a second rotational orientation.

Abstract: A process for producing thermoplastic resin products where granulated or particulate vulcanized rubber is sprayed by a heated heavy paraffin distillate composition to form a first intermediate mixture composition. The first intermediate mixture composition is passed through a heating chamber on a conveyor and combined with particulate thermoplastic scrap material in an approximating weight percentage of 30% thermoplastic material to 70% first intermediate mixture material. The combination forms a second intermediate mixture composition which is masticated in a masticator and extruded through a single screw feed mechanism for pelletizing and producing thermoplastic resin products which are useful for molding.

Abstract: A non-return valve for an injection molding machine is provided which includes a conventional tip member threaded into the end of a plasticating screw and carrying therewith an annular valve seat member. An annular check ring receives the tip member. Tang protuberances axially extend from the check ring to rotably engage the retainer end of the tip member. This causes the check ring to couple with the tip member during screw rotation to minimize valve wear while permitting the check ring to axially move relative to the tip member for effecting valve closure by pressure differentials in the normal manner. A ramp surface is provided on the tang protuberances which engages a drive surface on the retainer end of the tip/stud member upon reverse rotation of the screw through a predetermined rotational angle or for a set time to positively close the valve prior to injection.

Abstract: A blender for plastic materials weighs a charge of virgin plastic pellets as they are added to a hopper, similarly weighs plastics regrind material as it is added to the hopper, calculates the weight of color material (or other additive) on the basis of the actual virgin material weight and the desired color percentage, calculates from the weight of color material and a calibration of a volumetric feeder the volumetric amount of color material needed and then dispenses the calculated volume of color material. The apparatus is hybrid, using weight ratio measuring devices for the primary components and a volumetric feeder for dispensing the additives.

Abstract: There is provided an injection molding apparatus of the screw in-line type which has a screw having the following structural features and is used for injection-molding a high-nitryl resin.(1) A compression ratio is set to a value of 1.8 to 2.5.(2) Ratios of the lengths of the feed section, the compression section, and the metering section are set to[1 to 1.5]:[1.8 to 2.8]:[1].(3) A depth T (unit:mm) of groove of the metering section in relation to an inner diameter D (unit:mm) of the cylinder is set toT.gtoreq.0.057D-0.2.(4) A radius of curvature R (unit:mm) of the arc surface of the rear side corner portion which is formed between a screw shaft and a flight in relation to the inner diameter D (unit:mm) of the cylinder is set toR.gtoreq.0.36D+2.0.

Abstract: The extrusion screw for thermoplastic material comprises a helical thread, having a trapezoidal profile with a flat crest and inclined flanks, the pitch and the width or the root of which remains constant, while the inside diameter of the screw increases from the entry of the screw in the direction of the exit.