Abstract: A compression head for a machine for continuously densifying vegetable matter, wherein radial or virtually radial bars are included in the front face of the disc of the head and are made of a material presenting a coefficient of friction greater than that of the material of which the disc is made. The outer face of the bars is shaped so that the conventional ribs on the front face of the disc are continuous through the bars.

Abstract: This invention relates to a mixing device for a feed screw for melting and conveying plasticated material of the type which rotates about a longitudinal axis in a barrel of an apparatus for melting and conveying plasticated material. The feed screw includes consecutive feed, transition, and metering sections, and further includes at least one helical main channel for conveying material in a downstream direction. The mixing device includes a cylinder having a clearance from the inside of the barrel, which cylinder rotates with the feed screw about said axis within the barrel. The outer surface of the cylinder is provided with at least one continuous mixing channel which extends over the surface of the cylinder, the channel being disposed in alternate upstream and downstream directions wherein material conveyed in the mixing channel is caused to alternately reverse its direction while proceeding through the mixing channel.

Abstract: A mixer having an elongate barrel with an interior wall defining a mixing chamber, at least a pair of shafts extending axially within the barrel driven in the same direction of rotation and at the same speed of rotation, and mixing elements on each of the shafts. Radially opposite paddles are on each of the shafts, each comprising hub portions and wing portions radially spaced from the hub portions. The wing portions extend axially to overlie the hub portions and each wing portion has a radially inner surface generating the configuration of the radially inner surface of a wing portion on the radially adjacent paddle and further has a radially outer surface generating hub portions of the radially adjacent paddle, and the wall of the chamber.

Abstract: In a copending application Ser. No. 298,065 filed Aug. 31, 1981 modular mixing apparatus has been disclosed combined with a barrel and main power driven extruder screw and the mixing apparatus is necessarily required to be at the same speed as the main power driven extruder screw and operates through a common barrel member.In the present invention improved modular mixing apparatus has been constructed and arranged to operate with independent drive means for rotation in a separate stationary sleeve member and extruded material leaving the main extruder screw and barrel is introduced into the mixing module. The mixing apparatus may, in this form, be driven at variable speeds which are independent of the speed of the main extruder screw.The improved modular mixing apparatus of this invention also includes a newly devised shearing lug module.

Abstract: An extrusion apparatus for the production of mixtures of molten synthetic material includes a gear pump which is provided in the flow of molten material. The gear pump comprises a housing and two meshing gear pump wheels. The line joining the centers of the two wheels extends at right angles to the central longitudinal axis of the hollow cylinder. Outlet and inlet openings are formed in the cylinder of the extrusion apparatus which lead directly into the gear pump housing into regions which are, respectively, upstream and downstream of the gear wheels. The major surfaces of the gear wheels are disposed horizontally relative to the central longitudinal axis of the hollow cylinder.

Abstract: A helically moving fluid body leaving an extruder screw and brought into contact with rotating shearing means, undergoes laminar displacement, is then guided through a stationary sleeve along undulating linear paths of travel of relatively short axial length, and thereafter undergoes further laminar displacement and discharges into a die.During movement of the fluid mixture along the undulating linear paths of travel subdivision and blending of substantially all of the material in the fluid body, which is not in a fluid state, takes place. Thereupon the blended mixture is advanced to a die member at a desired fluidity and temperature in response to die requirements. Heating of the barrel is significantly reduced and energy conservation of an appreciable nature is achieved.In carrying out mixing as noted above there is employed a modular mixing apparatus constructed with multiple processing means suitable for shearing, kneading, flow diverting, dispersing, blending and the like.

Abstract: A process for the continuous glycolytic cleavage of polyurethane plastics waste in multi-shaft screw machines by the addition of optionally preheated diols, at a degradation temperature of 250.degree. C., while maintaining a pressure at least such that the polyurethane-diol mixture is in the liquid phase, by the discharge of the glycolysate mixture after short residence times of from 2 to 30 minutes in the reaction screw, and by rapid cooling of the glycolysate mixture.

Abstract: A helically moving fluid body leaving an extruder screw and brought into contact with rotating shearing means, undergoes laminar displacement, is then guided through a stationary sleeve along undulating linear paths of travel of relatively short axial length, and thereafter undergoes further laminar displacement and discharges into a die.During movement of the fluid mixture along the undulating linear paths of travel subdivision and blending of substantially all of the material in the fluid body, which is not in a fluid state, takes place. Thereupon the blended mixture is advanced to a die member at a desired fluidity and temperature in response to die requirements. Heating of the barrel is significantly reduced and energy conservation of an appreciable nature is achieved.In carrying out mixing as noted above there is employed a modular mixing apparatus constructed with multiple processing means suitable for shearing, kneading, flow diverting, dispersing, blending and the like.

Abstract: A continuous kneader comprising a rotary screw shaft and rotatable within a cylinder for transporting a fluid axially thereof, rotary disks mounted on the shaft and each formed on each side surface thereof with radial projections and recesses arranged alternately, and fixed disks provided on the cylinder and arranged on the opposite sides of each rotary disk coaxially therewith as opposed thereto. Each of the fixed disks is formed on each side surface thereof with radial projections and recesses arranged alternately. The boundary between and defining each projection and the recess adjacent thereto on at least one of the rotary disk and the fixed disk is inclined from the radial direction so that the material supplied from a space between the shaft and the inner surface of the cylinder to the space between the rotary disk and the fixed disk is passed over the rotary disk outer periphery toward the axis of the shaft into the space between the rotary disk and the fixed disk immediately adjacent thereto.

Abstract: Apparatus located at the output end of a screw extruder comprising a mandrel to rotate with said screw and a jacket coaxial with the mandrel and rotatable in an opposite direction of rotation to the mandrel at a speed which is steplessly adjustable. Sealing lips co-operating with abrasion rings are preferably provided on relatively moving surfaces of the jacket and stationary housings and temperature adjustment means can be provided in the jacket and the mandrel.

Abstract: An apparatus for hydrolytic degradation of plastics in which plastic material is deposited into a tubular housing via a feed hopper. An elongated screw shaft has a first section in the form of a high pitch screw thread disposed below the feed hopper to receive and advance the material to a second section. The second section of the screw shaft is in the form of a lower pitch thread for compressing the plastic material and transferring it to a longer, third section in the form of kneading discs, from which material passes through an outlet nozzle section to a cyclone separator where trapped gases and liquid may be withdrawn. The tubular housing is vented upstream of the feed hopper and a water inlet pipe is disposed adjacent to the second section of the screw shaft, downstream of the feed hopper. The outlet nozzle section is provided with pressure measuring and regulating means and a liquid level measuring and regulating device.

Abstract: An extrusion apparatus and method for producing foamed resin coatings on a wire. A foaming agent and molten resin are poured into a supply portion of an extruding screw and cylinder apparatus. The screw in the supply portion is tapered in the down stream direction. The screw and cylinder apparatus portion adjacent to the supply portion is arranged to blend the resin and foaming agent and has a lower coefficient of extrusion than the supply portion. The metering portion of the screw and cylinder apparatus is adjacent and down stream of the blend portion and has a higher coefficient of extrusion than the blend portion.

Abstract: A vented injection molding machine adapted to handle a wide variety of synthetic resinous materials without predrying is disclosed. The molding machine includes a two-stage screw rotatably and reciprocably mounted within a barrel. The barrel includes a pair of ends, a feed opening at one end and a vent opening intermediate the pair of ends. A first stage of the screw essentially completes material plastication. The first stage has a protruding helical screw flight with a first pitch and includes a feed section communicating with the feed opening, a transition section, and a pumping section. A second stage of the screw includes a deep flighted vent section which communicates with the vent opening and the first stage pumping section, a short transition section and a relatively short second pumping section. The second stage also includes a protruding helical screw flight having a second pitch which is greater than the first pitch of the first stage.

Abstract: A continuous kneader includes a screw shaft rotatable within a cylinder, and rotatable disks fixedly mounted on the shaft for rotation therewith. Stationary disks are arranged in face-to-face opposed relation to the rotatable disks. Each of the opposed surfaces of the disks is formed with alternating ridges and furrows. The material is passed between the opposed disk surfaces while being subjected alternately to compressive and shearing forces. Grooves are formed in the inner peripheral surface of the stationary disk and a screw section is carried on the adjacent outer peripheral surface of the drive shaft to promote the axial advance of the material through the device.