Patents Assigned to Leistritz Extrusionstechnik GmbH
  • Patent number: 10948393
    Abstract: A rheometer for determining and/or monitoring the flow behavior of viscous fluids, in particular plastic melts and plastic solutions, includes a housing, in which at least one substantially rectilinear channel is formed between an inlet opening and an outlet opening, the channel having a rectangular cross section, and a plurality of pressure measuring devices which are arranged along the channel, wherein the channel is provided over its length with a cyclically narrowing and widening cross section.
    Type: Grant
    Filed: February 1, 2017
    Date of Patent: March 16, 2021
    Assignee: LEISTRITZ EXTRUSIONSTECHNIK GMBH
    Inventor: Jürgen Miethlinger
  • Patent number: 10508980
    Abstract: The invention relates to a measuring nozzle for determining the extensional viscosity of polymer melts during their processing, comprising a flow channel which has a rectangular cross-section and which has a transitional section (3) between an inlet section (1) and an outlet section (2) with respective constant cross-section, which transitional section tapers hyperbolically in the flow direction (8) between two mutually opposite channel walls (6 and 7).
    Type: Grant
    Filed: June 7, 2016
    Date of Patent: December 17, 2019
    Assignee: Leistritz Extrusionstechnik GmbH
    Inventors: Jürgen Miethlinger, Bernhard Löw-Baselli, Hans Jürgen Luger
  • Publication number: 20180231445
    Abstract: The invention relates to a measuring nozzle for determining the extensional viscosity of polymer melts during their processing, comprising a flow channel which has a rectangular cross-section and which has a transitional section (3) between an inlet section (1) and an outlet section (2) with respective constant cross-section, which transitional section tapers hyperbolically in the flow direction (8) between two mutually opposite channel walls (6 and 7).
    Type: Application
    Filed: June 7, 2016
    Publication date: August 16, 2018
    Applicant: Leistritz Extrusionstechnik GmbH
    Inventors: Jürgen Miethlinger, Bernhard Löw-Baselli, Hans Jürgen Luger
  • Patent number: 9891619
    Abstract: A device for checking the construction of an extruder screw having a shaft and screw elements that are to be pushed or have been pushed one after the other onto the shaft in a defined sequence. Each screw element has an element-specific external geometry. A recording device being provided for determining information concerning the sequence of the screw elements that are to be pushed on or have been pushed on and for comparing the information determined with target information, which directly or indirectly describes the target sequence.
    Type: Grant
    Filed: November 24, 2014
    Date of Patent: February 13, 2018
    Assignee: LEISTRITZ EXTRUSIONSTECHNIK GMBH
    Inventors: Frank Rechter, Sven Wolf
  • Patent number: 9302419
    Abstract: An extruder having an operative unit composed of a cylinder and at least two screw shafts which are rotatably accommodated therein, a gear unit having at least two output shafts, wherein each output shaft, via a connecting element, is connected in a rotationally fixed manner to one screw shaft, a motor which drives the gear unit and is coupled to the gear unit via a clutch, and a controller installation, wherein each connecting element or each output shaft is assigned a separate measuring installation for determining the applied torque, wherein the measuring installations communicate with the controller installation which, depending on the individual determined torques, controls the clutch which is implemented as a switchable clutch, wherein the controller installation is configured for opening the clutch both when a determined torque exceeds a torque limit value and also when the difference between the two determined torques exceeds a limit value.
    Type: Grant
    Filed: August 7, 2014
    Date of Patent: April 5, 2016
    Assignee: LEISTRITZ EXTRUSIONSTECHNIK GMBH
    Inventors: Frank Rechter, Sven Wolf
  • Patent number: 8523021
    Abstract: A feeding device, particularly for feeding powdered materials into a device processing the same, in particular an extruder, the feeding device including a housing with a receiving region for receiving the material, which is movable laterally over at least one flexible wall, which is movable by at least one moving mechanical element acting thereon, wherein the element is movable along the wall. The wall exterior has bumps, is moved via the element, and/or the element is non-round in its motion.
    Type: Grant
    Filed: April 23, 2010
    Date of Patent: September 3, 2013
    Assignee: Leistritz Extrusionstechnik GmbH
    Inventors: Wolfgang Walter, Robert Rein
  • Publication number: 20120037665
    Abstract: A feeding device, particularly for feeding powdered materials into a device processing the same, in particular an extruder, the feeding device including a housing with a receiving region for receiving the material, which is movable laterally over at least one flexible wall, which is movable by at least one moving mechanical element acting thereon, wherein the element is movable along the wall. The wall exterior has bumps, is moved via the element, and/or the element is non-round in its motion.
    Type: Application
    Filed: April 23, 2010
    Publication date: February 16, 2012
    Applicant: LEISTRITZ EXTRUSIONSTECHNIK GMBH
    Inventors: Wolfgang Walter, Robert Rein
  • Patent number: 7954991
    Abstract: The present invention is directed to a materials extrusion device including a screw extruder with a plunger feeder. It includes a screw extruder having a main housing, a materials advancing screw, a screw drive mechanism, a feed port for inputting materials to be extruded and an extrusion outlet port. It also includes a plunger feeder having an elongated, upwardly biased (non-horizontal) plunger housing, e.g., a cylinder, with a plunger. A plunger drive mechanism is connected to the plunger to move the plunger upwardly and downwardly within the plunger housing, and there is a feed outlet at an upper end of the plunger housing, the feed outlet being connected to the screw extruder feed port.
    Type: Grant
    Filed: November 9, 2007
    Date of Patent: June 7, 2011
    Assignee: Leistritz Extrusionstechnik GmbH
    Inventors: Charles Martin, Elliott Gilbert