Patents by Inventor Lefteris N. Valsamis

Lefteris N. Valsamis has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5487602
    Abstract: Multi-screw, extrusion-compounding machines having co-rotating screw assemblies incorporating sets of modular mixing elements of non-symmetrical geometries with relatively large wing tip clearances. These sets of non-symmetrical modular mixing elements are removably mountable at any suitable axial locations along their respective rotationally-driven screw shafts for optimizing performance in relationship to particular plastic material and particular additives being compounded. The non-symmetrical geometries provide dynamic wedging pressurization for repeatedly propelling relatively large circumferential flows of the plastic material through large shear clearances. Due to the relatively large shear clearances, the plastic material is mixed at less elevated and more uniform temperatures than usually occurs with use of prior symmetrical kneading blocks or kneading discs. At less elevated temperatures most plastic materials exhibit increased viscosities.
    Type: Grant
    Filed: June 3, 1994
    Date of Patent: January 30, 1996
    Assignee: Farrel Corporation
    Inventors: Lefteris N. Valsamis, Eduardo L. Canedo, Jose M. Pereira, Douglas V. Poscich
  • Patent number: 4711581
    Abstract: A rotary processor has enclosed processing passages defined by channels in the rotor and a stationary coaxial closure. At least one processing passage is used as a stabilizing passage and another as a metering passage, whose volume and cross section are less than the stabilizing passage. A feed of plastic or polymeric material enters the stabilizing passage and may be subject to fluctuations or disturbances arising in external upstream equipment or within upstream stages of the processor itself. Substantially all material in the stabilizing passage is diverted through a first transfer passage to an entrance into the metering passage. An adjustable metering (throttling) element allows a controlled first flow of material to be carried downstream through an adjustable gap between this metering element and the bottom of the metering passage. This controlled first flow is discharged for providing material having uniform flow or at least a marked reduction in such fluctuations and disturbances.
    Type: Grant
    Filed: March 4, 1987
    Date of Patent: December 8, 1987
    Assignee: Farrel Corporation
    Inventors: Pradip S. Mehta, Lefteris N. Valsamis, Gary S. Donoian
  • Patent number: 4606646
    Abstract: Novel rotary processors and devolatilizing methods which provide extremely efficient devolatilization of materials, including viscous and visco-elastic materials and which involve a devolatilizing stage including a rotatable element carrying a plurality of annular channels and a stationary element providing a coaxial closure surface operationally arranged with the channels to provide enclosed processing passages. Each passage of the devolatilizing stage includes inlet means, outlet means and a channel blocking member all associated with the stationary element and arranged and adapted so that material fed to the inlet can be carried forward by the rotatable channel walls to the blocking member for discharge from the passage. The passages are interconnected by material to transfer grooves formed in the closure surface and operationally communicate with a vacuum source to provide a highly efficient devolatilizing stage.
    Type: Grant
    Filed: March 8, 1985
    Date of Patent: August 19, 1986
    Assignee: USM Corporation
    Inventors: Pradip S. Mehta, Lefteris N. Valsamis, Zehev Tadmor
  • Patent number: 4529478
    Abstract: Novel rotary processors which involve a devolatilizing stage including a rotatable element carrying a plurality of annular channels and a stationary element providing a coaxial closure surface operationally arranged with the channels to provide enclosed processing passages. Each passage of the devolatilizing stage includes inlet means, outlet means and a channel blocking member all associated with the stationary element and arranged and adapted so that material fed to the inlet can be carried forward by the rotatable channel walls to the blocking member for discharge from the passage. The passages are interconnected by material transfer grooves formed in the closure surface.The rotary processors of this invention include a novel vacuum system to evacuate the devolatilizing stage.
    Type: Grant
    Filed: September 14, 1983
    Date of Patent: July 16, 1985
    Assignee: USM Corporation
    Inventors: Pradip S. Mehta, Lefteris N. Valsamis
  • Patent number: 4529320
    Abstract: Novel rotary processors and devolatilizing methods which provide extremely efficient devolatilization of materials, including viscous and visco-elastic materials and which involve a devolatilizing stage including a rotatable element carrying a plurality of annular channels and a stationary element providing a coaxial closure surface operationally arranged with the channels to provide enclosed processing passages. Each passage of the devolatilizing stage includes inlet means, outlet means and a channel blocking member all associated with the stationary element and arranged and adapted so that material fed to the inlet can be carried forward by the rotatable channel walls to the blocking member for discharge from the passage. The passages are interconnected by material to transfer grooves formed in the closure surface and operationally communicate with a vacuum source to provide a highly efficient devolatilizing stage.
    Type: Grant
    Filed: September 14, 1983
    Date of Patent: July 16, 1985
    Assignee: USM Corporation
    Inventors: Pradip S. Mehta, Lefteris N. Valsamis, Zehev Tadmor
  • Patent number: 4527900
    Abstract: Novel rotary processors including sealing means to control leakage of pressure and/or material between processing passages which are maintained at significantly different pressure levels. The processors comprise a rotatable element carrying a plurality of annular channels and a stationary element providing a coaxial closure surface operationally arranged with the channels to provide enclosed processing passages. Each passage includes inlet means, outlet means and a channel blocking member all associated with the stationary element and arranged and adapted so that viscous material fed to the inlet can be carried forward by the rotatable channel walls to the blocking member for discharge from the passage. The passages are interconnected by material transfer grooves formed in the closure surface.
    Type: Grant
    Filed: September 14, 1983
    Date of Patent: July 9, 1985
    Assignee: USM Corporation
    Inventors: Pradip S. Mehta, Lefteris N. Valsamis
  • Patent number: 4421412
    Abstract: Novel and improved processes and apparatus for processing particulate materials which can be converted to the liquid state. Essentially, the process and apparatus involve feeding a particulate material to an annular processing passage for melting and controlled processing. The annular processing passage is provided by a rotatable element carrying at least one processing channel, and a stationary element which provides a complementary, coaxial surface arranged with the channel to provide the enclosed processing passage. Also associated with the stationary element are an inlet for feeding material to the passage, an outlet for discharging material, a material collecting end wall surface for the passage and a member or members extending into the processing channel providing a material restraining surface between the inlet and outlet and occupying a predetermined portion of the melt pool space between the end wall and the restraining surface.
    Type: Grant
    Filed: November 24, 1982
    Date of Patent: December 20, 1983
    Assignee: USM Corporation
    Inventors: Peter Hold, Zehev Tadmor, Lefteris N. Valsamis
  • Patent number: 4411532
    Abstract: A novel, improved rotary processor comprising a rotatable element carrying a plurality of processing channels and a stationary element having a coaxial closure surface operationally arranged with the channels to provide a plurality of enclosed processing passages. The plurality of passages provide interconnected processing stages including a first processing stage and a second processing stage having inboard and outboard sections separated by a third processing stage.
    Type: Grant
    Filed: January 4, 1982
    Date of Patent: October 25, 1983
    Assignee: USM Corporation
    Inventors: Lefteris N. Valsamis, Jan-Chin Yang, Gary S. Donoian
  • Patent number: 4402616
    Abstract: A multi-stage rotary processor particularly useful for processing plastic and polymeric materials. The multi-stage rotary processor includes a rotatable element carrying a plurality of processing channels and a stationary element providing a coaxial closure surface cooperatively arranged with the channels to provide a plurality of enclosed processing passages. Also associated with the stationary element are inlets, outlets and blocking members for each passage and arranged so that material fed to the passage can be dragged forward by the channel walls, and collected at the blocking member for discharge from a passage(s) of one stage to a passage of another. The geometry of the passage receiving material is selected to provide optimum processing efficiency, resulting in a processing rate capability for that passage greater than the rate at which material is supplied to the passage.
    Type: Grant
    Filed: January 4, 1982
    Date of Patent: September 6, 1983
    Assignee: USM Corporation
    Inventors: Lefteris N. Valsamis, Gary S. Donoian
  • Patent number: 4389119
    Abstract: Novel, improved rotary processors which include a rotatable element carrying a plurality of annular channels and a stationary element providing a coaxial, closure surface operationally arranged with the channels to provide enclosed processing passages. The so-formed plurality of processing passages provide a highly efficient processing stage particularly for melting polymer material. Each processing passage of the processing stage includes inlet means, outlet means and a channel member associated with the stationary element and arranged and adapted so that material fed to the inlet can be carried forward by the rotatable channel walls to the blocking member for discharge from the passage.In rotary processors of this invention the clearance between the rotary surface carrying the channels and the stationary coaxial closure surface is relatively wide and permits substantial amounts of material to be interchanged between passages of the processing stage.
    Type: Grant
    Filed: January 4, 1982
    Date of Patent: June 21, 1983
    Assignee: USM Corporation
    Inventors: Lefteris N. Valsamis, Zehev Tadmor
  • Patent number: 4255059
    Abstract: Improved means for aligning processing members at various positions in processing passages of rotary processors. Essentially, the alignment means (or alignment elements) comprise a non-rotatable member positioned in the processing passage and shaped to at least partially interfere with flow of material in the passage. The shaped member is designed to perform certain processing functions on material in the passage such as blocking, collecting, mixing, spreading, restraining etc. The member is positioned so as to be non-rotative with the passage but is flexibly supported so as to "float" axially in the passage and is self-centering in the passage by hydrodynamic action.
    Type: Grant
    Filed: December 20, 1978
    Date of Patent: March 10, 1981
    Assignee: USM Corporation
    Inventors: Peter Hold, Zehev Tadmor, Lefteris N. Valsamis
  • Patent number: 4213709
    Abstract: A multi-stage rotary processor particularly useful as a pump for viscous materials. The multi-stage rotary processor includes a rotatable element having a surface carrying at least one primary processing channel connected to at least one further processing channel and a stationary element providing a complementary coaxial surface arranged with the channels to form enclosed primary and further processing passages. The stationary element also has associated with it an inlet for at least the primary processing passage, outlets for the passages and members extending into each channel for blocking material fed to the processing passages so that liquid material in contact with the rotating channel walls can be dragged forward in each channel. In the primary processing passage the dragged forward material is transferred to the further processing passage for discharge at a uniform pressure and rate.
    Type: Grant
    Filed: December 1, 1978
    Date of Patent: July 22, 1980
    Assignee: USM Corporation
    Inventor: Lefteris N. Valsamis