Abstract: Various methods and systems are provided for mixing and dispensing viscous materials for the creation of additive structures. As one example, during a mixing and dispensing operation with a mixing and dispensing head of a multi-dimensional printing apparatus, linear movement of a mixing rod positioned within a mixing chamber of the mixing and dispensing head, at least along a central axis of the mixing chamber, is adjusted based on an operating condition of the printing apparatus and dispensing of mixed liquids from the mixing and dispensing head is stopped by stopping one or more pumps fluidly coupled to the mixing chamber and linearly moving the mixing rod upward and away from a dispensing nozzle of the mixing and dispensing head.

Abstract: Various methods and systems are provided for mixing and dispensing viscous materials for the creation of additive structures. As one example, during a mixing and dispensing operation of a multi-dimensional printing apparatus, one or more liquids may flow into a mixing chamber via one or more material inlets arranged in a wall of the mixing chamber below a high pressure bearing of a mixing rod positioned within the mixing chamber; and movement of a mixing rod positioned within the mixing chamber is adjusted based on an operating condition of the printing apparatus.

Abstract: An accumulator for storing fluid that includes a shell that defines an interior volume of the accumulator. The shell includes at least one port for providing fluid to a fluid system. The accumulator also includes an accumulator shaft disposed in the interior volume and extending at least partially across the interior volume from a first interior surface of the shell along a longitudinal axis of the shell, e.g., a central axis. The accumulator includes a piston-plate disposed in the interior volume such that the piston-plate and a second interior surface of the shell define a chamber in the interior volume. The accumulator further includes a motor disposed in the interior volume. The accumulator is configured such that rotational movement of the motor translates to linear movement of the piston-plate along the accumulator shaft.

Abstract: A nozzle apparatus used for extruding a material includes an internal spindle that imparts motion into the extruding material, the internal spindle having a base; a multiple degree-of-freedom pivot at the base of the internal spindle, and a drive mechanism that controls the motion of the internal spindle. In one embodiment the material is a semi-solid metal or alloy. In another embodiment the material is a shear thinning mixture or material. In yet embodiment the material is a thixotropic mixture or material. The nozzle apparatus can be used for making a three-dimensional object with the steps of providing a material; providing a nozzle that extrudes the material, the nozzle having an internal spindle that imparts motion into the material; positioning the nozzle above a support structure; and moving the nozzle in a three-dimensional pattern while extruding the material through the nozzle onto the support structure or onto the material previously deposited.

Abstract: A dynamic mixer for mixing flowable media, which has a mixing chamber in a multipart housing is described. A plurality of inlets and an outlet of the mixing chamber are arranged on the housing, and a mixing shaft having a mixer section projects into the mixing chamber. The mixing shaft is mounted in a sliding bearing in the housing by means of a bearing section and passes through the housing with a drive section for coupling to a drive. To avoid dead spaces within the housing, the housing has a sealing hole for accommodating the drive section of the mixing shaft and a bearing hole for mounting the bearing section of the mixing shaft, where the sealing hole has a greater diameter than the bearing hole in order to accommodate a sealing means.

Abstract: An extruding device includes an extruder cylinder, a screw, and a rotary drive for the screw. To facilitate installation and removal of the assemblies of the extruding device, the screw end facing the rotary drive does not protrude during operation into bearings provided between the extruder cylinder and rotary drive, particularly not into a thrust bearing.

Abstract: A gear box for a reciprocating kneader. A primary rotational gear is attached to a gear box primary shaft and rotates in concert therewith. A secondary rotational gear is engaged with the primary rotation gear and rotates therewith. A secondary shaft is attached to the secondary rotational gear and rotates therewith. A primary oscillation gear is attached to the gear box primary shaft and rotates therewith. A secondary oscillation gear is rotationally engaged with the primary oscillation gear and rotates on the secondary shaft. An eccentric is coupled to the secondary oscillation gear and rotates in concert therewith. A yoke is engaged with the eccentric and oscillates on an axis perpendicular to the secondary shaft in response to the lobe. The gearbox secondary shaft moves along its axis in concert with yoke oscillation. A housing is pivotally attached to the yoke and pivotally attached to a casing at a casing.

Abstract: A mixing and kneading machine (1) for continual compounding comprises a screw shaft (3) rotating in a casing (2) and simultaneously moving axially translationally. To sustainably enhance the efficiency of the machine as regards its material thruput per unit of time the screw shaft (3) comprises at least four groups of radial screw vanes (4a, 4b, 4c, 4d) evenly distributed circumferentially, each group consisting of a plurality of screw vanes in axial sequence. The outer diameter (Da) of the screw shaft ranges from 400 to 800 millimeters. The rotary speed of the screw shaft (3) ranges from 30 to 80 rpm. A mixing and kneading machine (1) engineered as such is particularly suitable for compounding an anodic mass in the production of electrodes—anodes—for the aluminum industry.

Abstract: A kneading apparatus for a thermoplastic resin, includes: a plasticizing cylinder which has a high pressure kneading zone and a pressure reduction zone; a screw in the plasticizing cylinder; a downstream side seal mechanism which shuts off communication between the high pressure kneading zone and the pressure reduction zone; and a pressure reduction zone pressure adjusting mechanism which is connected to the pressure reduction zone and which controls a pressure of the pressure reduction zone so that the pressure is not less than an atmospheric pressure and the pressure is not more than a maximum pressure of the high pressure kneading zone that is achieved when kneading a molten resin with a pressurized fluid, when the downstream side seal mechanism shuts off the communication between the high pressure kneading zone and the pressure reduction zone.

Abstract: In an agitation mixing apparatus 51 which includes: a casing 52 having a flow path 56 in which a fluid flows; an agitator 53 which is disposed inside the casing 52 and includes a shaft 57 and a vane 58 mounted around the shaft 57; and a drive source 59, connected to the shaft 57, for vibrating the agitator 53 in an axial direction, grooves 71 are provided on an inner wall surface of the casing 52 at predetermined intervals in the axial direction.

Abstract: A kneading apparatus for a thermoplastic resin, includes: a plasticizing cylinder which has a high pressure kneading zone and a pressure reduction zone; a screw in the plasticizing cylinder; a downstream side seal mechanism which shuts off communication between the high pressure kneading zone and the pressure reduction zone; and a pressure reduction zone pressure adjusting mechanism which is connected to the pressure reduction zone and which controls a pressure of the pressure reduction zone so that the pressure is not less than an atmospheric pressure and the pressure is not more than a maximum pressure of the high pressure kneading zone that is achieved when kneading a molten resin with a pressurized fluid, when the downstream side seal mechanism shuts off the communication between the high pressure kneading zone and the pressure reduction zone.

Abstract: The present invention relates to a method and to a device for injection molding plastic material, wherein the starting plastic material to be treated is first subjected to a pretreatment, wherein the plastic material is heated in a receiving container at a temperature below the melting temperature while constantly being mixed, and thereby at the same time is crystallized, dried and/or cleaned and/or the intrinsic viscosity thereof is increased. According to the invention, the plastic material pretreated in this way is transferred into a screw injection molding machine (10) having a screw (16) rotating in a housing (17) and being axially displaceable therein and/or acting as a piston, is plasticized in said screw, and molded into a molded part, for example a preform.

Abstract: A biological or chemical reactor (2) has an inner vessel (4) disposed within an outer vessel (6) and an annular space (16) defined therebetween in which fluid is to be contained. The fluid comprises reactants of a biological or chemical reaction. A reaction support (10a) is disposed in an opening in a wall of one of the vessels and is designed to support a structure such as a scaffold that receives fluid under pressure from the annular space. The reactor generates hydrodynamic pressure and shear stress in the fluid within the annular space, upon relative rotational movement between the vessels so as to drive the fluid through intersticies in the scaffold.

Abstract: Base compositions for addition-crosslinking silicone compositions are continuously produced by, in a first stage, homogeneously mixing and kneading organopolysiloxanes and flowable prehydrophobized oxidic reinforcing fillers in a continuous kneading machine with kneading chambers arranged alongside one another. In a second, downstream, stage of the process, the compositions produced in the first stage are subjected to aftertreatment in a mixing apparatus in which the compositions have been subjected to a mixing procedure with introduction of shear force.

Abstract: A method of processing metal, metallic alloys, and metal matrix composites in a plastics injection molding machine is disclosed. The method includes the steps of providing a plastics injection molding machine having a screw. A step of removing the screw is included in the method. A step of replacing the screw with a modified screw configured and arranged for processing metals is also included. Alternatively, a step of removing the flights from the middle portion of the original screw shaft may be included.

Abstract: A gear box for a reciprocating kneader. A primary rotational gear is attached to a gear box primary shaft and rotates in concert therewith. A secondary rotational gear is engaged with the primary rotation gear and rotates therewith. A secondary shaft is attached to the secondary rotational gear and rotates therewith. A primary oscillation gear is attached to the gear box primary shaft and rotates therewith. A secondary oscillation gear is rotationally engaged with the primary oscillation gear and rotates on the secondary shaft. An eccentric is coupled to the secondary oscillation gear and rotates in concert therewith. A yoke is engaged with the eccentric and oscillates on an axis perpendicular to the secondary shaft in response to the lobe. The gearbox secondary shaft moves along its axis in concert with yoke oscillation. A housing is pivotally attached to the yoke and pivotally attached to a casing at a casing.

Abstract: A mixing and kneading machine (1) for continual compounding comprises a screw shaft (3) rotating in a casing 2 and simultaneously moving axially translationally. To sustainably enhance the efficiency of the machine as regards its material thruput per unit of time a screw shaft is proposed having the following geometric ratios: Da/Di=1.5 to 2.0, i.e. the ratio of screw shaft outer diameter Da to screw shaft inner diameter Di is 1.5 to 2.0, Da/H=4 to 6, i.e. the ratio of screw shaft outer diameter Da to stroke H is between 4 and 6, T/H=1.3 to 2.5, i.e. the ratio of pitch T to stroke H is between 1.3 and 2.5. The mixing and kneading machine (1) provided with such a screw shaft (3) is operated preferably at a rotational speed exceeding 500 rpm, particularly exceeding 800 rpm.

Abstract: The drive device (1) is intended for a machine for the plasticization and injection of synthetic material. It comprises a main drive (2) drivable in a first and a second direction of rotation and having a hollow shaft (6) rotatable about an axis of rotation (4). An axially bipartite inner reception region (7) having a first part region (8) and a second part region (9) is formed by the hollow shaft (6). Rotation transmission means (10, 14), arranged at least partially in the first part region (8), are provided for the transmission of a rotational movement of the hollow shaft (6) solely in a first direction of rotation to an extruder worm (16) rotatable about the axis of rotation (4).

Abstract: A mixer-extruder assembly may include a hollow cylindrical chamber and a hopper connected to the chamber. A piston drive shaft having a piston attached at one end may be rotatable about a drive shaft axis that is coaxial with the cylindrical chamber. The piston may have one or more mixer blades coupled thereto and rotatable therewith. The piston may be controllably rotated about the drive shaft axis, after input material received by the hopper is delivered into the chamber, causing the mixer blades to rotate and mix the input material with mixing fluid introduced into the chamber. The piston may also be slidably movable from an upper end of the chamber toward the outlet port of the chamber, so that the mixed input material is extruded through the output port of the chamber.

Abstract: A process for preparing organopolysiloxane compositions (A) having a viscosity measured at 25° C. of at least 500 Pa·s., wherein organopolysiloxanes (O) and fillers (F) are mixed and kneaded in a first process stage in a kneading cascade having at least two kneading chambers arranged in series adjacent one another, each containing kneading tools having parallel axes and capable of being driven in co-rotating or counter-rotating directions, the chambers connected to one another by means of openings through which material can pass in a direction transverse to the axes of the kneading tools, with the first kneading chamber having a feed opening and the last kneading chamber having a discharge opening, to give raw mixtures, and the raw mixtures are kneaded and degassed in a reciprocating kneader in a second process stage.

Abstract: A device for processing material by mixing and/or plasticization or agglomeration has a screw housing, in which at least two screws are situated adjacent to one another. The screw channels are engaged with one another. The screws are driven to rotate by at least one motor. The screws are supplied with the material through an intake opening of the screw housing and the processed material leaves the screw housing through at least one outlet opening. An apparatus is provided, which in operation of the device provides the gap which exists between adjacent screw channels of the screws alternately with a periodic enlargement or reduction, which is superimposed on the rotational movements of the two screws. In the method for material processing, the material, in addition to the compaction which is caused by the conveyance action of the screws, is subjected to periodic squeezing by the screws.

Abstract: The drive device (1) is intended for a machine for the plasticization and injection of synthetic material. It comprises a main drive (2) drivable in a first and a second direction of rotation and having a hollow shaft (6) rotatable about an axis of rotation (4). An axially bipartite inner reception region (7) having a first part region (8) and a second part region (9) is formed by the hollow shaft (6). Rotation transmission means (10, 14), arranged at least partially in the first part region (8), are provided for the transmission of a rotational movement of the hollow shaft (6) solely in a first direction of rotation to an extruder worm (16) rotatable about the axis of rotation (4).

Abstract: A method for dosing an additive in an injection-moulding unit, and an injection-moulding unit. The injection-moulding unit (1) comprises a screw (2) that comprises at least a feed zone (4). The injection-moulding unit (1) also comprises feed devices (7) that dose the plastic raw material into a space between the screw (2) and a cylinder through a feed opening (9) onto the feed zone (4) of the screw. The additive is fed to the feed zone (4) of the screw from the dosing channel (10) that opens into the space between the screw (2) and cylinder (3) in the flow direction of the plastic raw material.

Abstract: The present invention relates to a method for the continuous mixing of at least one polyol component and at least one isocyanate component and optionally additives to form a polyurethane reaction mixture in a stirrer mixer with an axially conveying stirrer.

Abstract: An injection molding screw for metal injection molding includes a first end, a second end, a longitudinal body with a first stage and a second stage extending axially along a length of the screw between the ends, a pressure retention device, and optionally, a screw tip. The pressure retention element minimizes loss of pressure in the second stage portion.

Abstract: A continuous process of preparing a heat-vulcanizable filled silicone composition, comprises mixing filler and high viscosity silicone polymer continuously in a first co-rotating intermeshing twin screw extruder; and compounding a filler and silicone polymer mixture from the first extruder in a second single shaft reciprocating extruder. Another continuous process of preparing a heat-vulcanizable filled silicone composition, comprises forming a premix? of filler and high viscosity silicone polymer; mixing the premix and additional high viscosity silicone polymer continuously in a co-rotating intermeshing twin screw extruder; and compounding a filler and silicone polymer mixture from the co-rotating intermeshing twin screw extruder in a second single shaft reciprocating extruder.

Abstract: An injection screw and barrel for small injection molding shots employs separate plunger and flight sections so that the plunger section may be arbitrarily reduced in diameter without adversely affecting the threaded portion of the flight section. Melt passes from the flight section to a metering area through a hollow bore in the plunger section.

Abstract: A system for delivering elastomeric media comprises a gear pump and a screw-type extruder which, viewed in the delivery direction of the pumping medium, is arranged in front of the gear pump and which comprises a screw and a screw casing. The screw casing has at least one conical part, and the screw has at least one tapering in the area of the conical part. For the controlled feeding of energy into the pumping medium, the screw is axially displaceable in the screw casing.

Abstract: An injection screw and barrel for small injection molding shots employs separate plunger and flight sections so that the plunger section may be arbitrarily reduced in diameter without adversely affecting the threaded portion of the flight section. Melt passes from the flight section to a metering area through a hollow bore in the plunger section.

Abstract: The invention is an extruder temperature controller for an extruder barrel. The extruder temperature controller includes means for determining an actual screw speed and has means for storing a plurality of screw speeds. Each member of the plurality of stored screw speeds has a corresponding stored temperature reset value. The extruder temperature controller has a means for comparing and selecting that compares the actual screw speed to each of the plurality of stored screw speeds and selectes a default screw speed. The default screw speed has a smaller deviation from the actual screw speed than any other member of the compared, stored screw speeds. The controller further includes a means for generating a control output driver signal to the heat exchange means. The control output driver signal is the corresponding stored temperature reset value for the default screw speed.

Abstract: An electric injection molding machine comprises a barrel which holds a screw therein, a voice coil type linear motor which moves the screw in the axial direction thereof. The linear motor has a coil, a yoke extending along the coil, and a magnet movable relatively to the coil in the axial direction thereof. The injection molding machine comprises a coolant passage in the yoke and a cooling device for cooling the coil. Temperature related to the coil or a coolant is detected, and the coolant is control in accordance with the detected temperature.

Abstract: An apparatus for injection molding two compatible polymeric materials, in which two substantially coaxial extrusion screws are used to plasticize the two materials into a common accumulation space. The charge comprising multiple layers of material is then injected into a closed mold by means of forward axial motion of the outer screw with respect to its enclosing barrel. Once inside the mold, the first material forms a skin layer totally or partially surrounding the other material. In this way a part having a plurality of material properties may be produced in a single operation.

Abstract: The invention relates to a system for delivering elastomeric media, the system consisting of a gear pump (1) and a screw-type extruder (10) which, viewed in the delivery direction (6) of the pumping medium, is arranged in front of the gear pump (1) and which consists of a screw (11) and of a screw casing (12).

Abstract: A plasticizing apparatus used for a pre-plasticization-type injection molding machine is equipped with a screw drive section which comprises a rotational drive section supported in an axially moveable manner and adapted to rotate the screw; and an advancement/retraction drive section including a servomotor and a ball-screw mechanism for converting rotational motion of the servomotor to linear motion in order to axially move the rotational drive section. By virtue of the above-described structure, the screw disposed within the barrel is rotated by the rotational drive section of the screw drive section, so that the molding material within the barrel is plasticized (melted) and is then supplied to the injection apparatus. Further, the rotational drive section (screw) is advanced and retracted by the advancement/retraction section of the screw drive section, so that the resin passage of the barrel is opened and closed in accordance with the position of the screw.

Abstract: An extruder screw mechanism has a barrel that is heated by heating coils, an internal screw, and a cylindrical melt sleeve having a plurality of circumferentially spaced, axially extending, radial slots there through located between the external barrel and the internal screw. Another embodiment of the extruder has a barrel and an internal screw, with the internal screw having either a single central axial bore or a plurality of internal axial bores. The internal screw is provided with a plurality of external threads, with the threads each having a curved starting portion with a helix angle that has a finite value and gradually increases along an initial portion of the screw until the threads are substantially linear and parallel to the axis of the screw along the melting portion of the screw; a related embodiment has threadless portion separating the linear threads from the curved upstream threads.

Abstract: High levels of treated fumed silica, processing fluid and high molecular weight silicone polymer are continuously compounded into a homogeneous silica filled heat-vulcanizable silicone composition by forming a premix in a continuous annular layer mixer and continuously discharging the premix into a compounding apparatus for compounding to form the filled heat-vulcanizable silicone composition.

Abstract: There is provided an injection apparatus comprised of a heating cylinder which is closed by a front end member having a nozzle. The apparatus is further comprised of a plasticating screw in the heating cylinder in a freely rotating and reciprocating manner, and a plunger connected to the front end of the screw. The plunger has a conical front end in which flow channels are formed. The front end member has a measuring chamber formed therein at an internal central location thereof. The measuring chamber has a predetermined length and an internal diameter which is reduced by 8 to 15% with respect to an internal diameter of the heating cylinder. The diameter of the injection plunger is set almost equal to the diameter of the measuring chamber, whereby the injection plunger is inserted into the measuring chamber in a freely reciprocating manner.

Abstract: A motor-driven injection molding machine comprises an injection device which includes a heating cylinder for heating resin powder therein to melt the resin powder into molten resin and a screw disposed in the heading cylinder for feeding the molten resin in the heating cylinder forward to meter the molten resin. A controller positions, in response to a position detected signal detected by a position detector, the screw at a metering position using an injection servomotor on and immediately after completion of the plasticization and metering process. In addition, the controller rotates, in response to a pressure detected signal detected by a load cell, the screw in the opposite direction using a screw-rotation servomotor on and immediately after the completion of said plasticization and metering process to carry out depressurization of the molten resin in the heating cylinder that is metered ahead of the screw.

Abstract: A plasticizing apparatus used for a pre-plasticization-type injection molding machine is equipped with a screw drive section which comprises a rotational drive section supported in an axially moveable manner and adapted to rotate the screw; and an advancement/retraction drive section including a servomotor and a ball-screw mechanism for converting rotational motion of the servomotor to linear motion in order to axially move the rotational drive section. By virtue of the above-described structure, the screw disposed within the barrel is rotated by the rotational drive section of the screw drive section, so that the molding material within the barrel is plasticized (melted) and is then supplied to the injection apparatus. Further, the rotational drive section (screw) is advanced and retracted by the advancement/retraction section of the screw drive section, so that the resin passage of the barrel is opened and closed in accordance with the position of the screw.

Abstract: The present invention is applicable to an injection molding machine comprising an injection device having a servo motor for use in rotating a screw and a controller for controlling the servo motor. The controller has a rotation speed N previously set therein as a set value for the screw rotation in a metering process. The controller rotates the screw at an acceleration A1 until the rotation speed of the screw reaches a value NK (where NK<N). After that the controller carries out a control operation to rotate the screw at an acceleration A2 until the rotation speed of the screw reaches the value N. The acceleration A2 is higher than the acceleration A1.

Abstract: A mixing and kneading device comprises a mixing and kneading shaft mounted in a housing and driven to a rotating as well as to a reciprocating movement. For sealing the housing, there is provided a sealing assembly located between the housing and the mixing and kneading shaft. The sealing assembly includes a supporting assembly arranged between the housing and the mixing and kneading shaft and provided with first and second sealing means. The supporting assembly is locked against rotation, but coupled to the mixing and kneading shaft to perform therewith its reciprocating movement. The first sealing means serves for rotatively seal the mixing and kneading shaft and is located between the mixing and kneading shaft and the supporting assembly. The second sealing means provides for a translative sealing of the mixing and kneading shaft and is located between the supporting assembly and the housing.

Abstract: An extruder-mixer has a plurality of rotor rings provided on the downstream end of a motor driven extruder shaft mounted for rotation in a conventional heated barrel or stator. The rings comprise a plurality of spaced driven rotor rings spaced apart from each other and a plurality of non-driven but rotatable floating rings interleaved between each pair of driven rotor rings. Both rings have parallel upstream and downstream faces between which polymer flow passageways extend so that the polymer melt moves downstream first through one type of ring followed by movement through the other type of ring and the viscosity of the melt causes the rotatable floating rings to be rotated by the driven rings at a slower speed than the driven rings so that shearing force on the melt effects mixing of the melt.

Abstract: A screw adapted for plasticizing a fiber-reinforced thermoplastic resin wherein screw lead (distance of the resin advancement in the direction of the axis per 1 revolution of the screw when it is postulated that the screw channel is 100% filled with the resin) of the screw in its compression section decreases in the direction toward the forward end of the screw. A plasticizing apparatus wherein such screw is mounted. A method for molding a fiber-reinforced thermoplastic resin by using such an apparatus. A molded article produced by such molding method. In the present invention, shear force of sufficient level can be obtained to avoid the formation of clumps while breakage of the reinforcing fibers is avoided to leave long fibers in the molded article. The resulting molded article has excellent mechanical properties, and such article is quite useful as a material for use in automobile parts and other parts.

Abstract: An apparatus and method for continuously reducing the viscosity of molten moldable polymeric material uses shear vibration under extensional flow to cause disentanglement. One or more station treatment cavities are defined by a gap composed of two closely separated surfaces in relative motion with each other at given speed and/or submitted to relative oscillations, with given frequency and amplitude to produce a shear deformation on the molten moldable material and a controlled variation of the gap dimension. The surface have a contour profile of ribs and/or bumps and/or grooves over which the molten moldable material can flow and/or can be dragged and/or is being pushed through and/or pumped through. The treatment cavities have an inlet through which the molten moldable material can pass into, and an outlet through which it can exit each treatment cavity.

Abstract: An extrusion system is provided with a screen changer between in-line screw sections. An in-line seal diverts high pressure, high temperature foamable material toward the screen changer. The seal may have reverse flights to provide a visco-dynamic seal. The screw sections and the seal may be located in a common barrel housing. The screw sections and the seal may be integrally rotated as a single in-line unit. A device including an injection valve may be attached to the upstream screw section to introduce a foaming agent into the material being extruded.

Abstract: An injection molding machine includes an injection molding cylinder with a material supply at one end and an injection nozzle at the other end and a material conveyance unit attached to a drive and movable in the injection molding cylinder. The injection molding machine also includes a vibration element for inducing a flow of melt within the injection molding cylinder for homogenizing the melt.

Abstract: A method for controlling a screw injecting apparatus having a heating cylinder and a screw slidably and rotatably received in the heating cylinder and designed to carry out a plasticizing-metering phase in which a predetermined amount of a molten material is accumulated forwardly of the screw by plasticizing and kneading a raw molding material via the screw and the heating cylinder, a waiting phase in which the screw is held inactive for a period between completion of the metering and subsequent injection of the molten material, and an injecting phase in which the molten material is injected. The method comprises the step of causing the apparatus to vibrate the molten material at a predetermined low frequency axially of the screw during the plasticizing-metering phase. By vibrating the molten material at a low frequency during the relatively long plasticizing-metering phase, the viscosity of the molten material can be reduced.

Abstract: An injection molding unit is provided with a carrier block and an injection bridge, movable towards and away from the carrier block for a relative movement of a feeding means relative to a receiving body. An injection motor drives a plurality of spindle drives for generation of this injection movement. The injection bridge has a sparing or recess, in which the injection motor is placed.

Abstract: A method of mixing first and second molding components in a non-intermeshing twin screw compounder having a discharge opening wherein the first component is added around a first of the two rotating screws at a point remote from the discharge opening, the second component is added around the first screw nearer the discharge opening, vacuum is applied to the mixing components nearer the discharge opening, rotation of the two screws is stopped, and the second screw is axially moved toward the discharge opening to eject mixed components from the compounder and into a female mold.

Abstract: A plasticizing unit having a plasticizing screw, an injection piston connected to the screw, a quill connected to the piston, and hydraulic cavity formed by the piston and a quill end face. Hydraulic fluid is transferred to the hydraulic cavity to move the piston and screw away from the quill. The screw and piston are subsequently moved towards the quill to displace hydraulic fluid out of the hydraulic cavity and cause back pressure. The back pressure is counteracted by acting on the back of the quill.