Patents by Inventor Robert G. Andrus

Robert G. Andrus 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: 6192900
    Abstract: A method of cleaning precleaning the header of a used dialyzer is provided. The method includes providing a precleaner header selectively coupled to a dialyzer header cap. The precleaner header includes a needle having an inlet in fluid communication with a source of cleaning fluid and an outlet in fluid communication with the header cap. An incoming source of cleaning fluid is introduced into the needle at a pressure above ambient pressure and an incoming source of air is introduced at a pressure above ambient pressure into the incoming cleaning fluid stream. The cleaning fluid containing air is discharged into the dialyzer header and cleans the dialyzer header by circulating therewith in. A waste stream is generated and drained from the dialyzer header through the precleaner header.
    Type: Grant
    Filed: December 13, 1999
    Date of Patent: February 27, 2001
    Assignee: Minntech Corporation
    Inventors: Kevin R. Arnal, Robert G. Andrus, David A. Luhring, Jeffrey C. Toy
  • Patent number: 6050278
    Abstract: A dialyzer precleaning system for coupling a source of fluid to a used dialyzer. The precleaning system includes a precleaner header that includes a housing with a needle receiving channel and a connected waste discharge channel, a needle with a plurality of fluid discharge perforations is received within the needle assembly receiving channel, and a coupling arm for attaching the precleaner header to a dialyzer header cap. The needle protrudes into the dialyzer header so that fluid may be discharged through the inside of the needle out the fluid discharge perforations into the dialyzer header. Waste fluid from the dialyzer header is discharged back into the needle assembly receiving channel along the outside the needle into a fluidly connected waste discharge channel and out a waste discharge outlet. The needle may also rotate and retract.
    Type: Grant
    Filed: August 6, 1999
    Date of Patent: April 18, 2000
    Assignee: Minntech Corporation
    Inventors: Kevin R. Arnal, Robert G. Andrus, David A. Luhring, Jeffrey C. Toy
  • Patent number: 5762798
    Abstract: An asymmetrical, microporous, hollow fiber membrane is made from a polymeric dope mixture of polysulfone and polyvinyl pyrrolidone dissolved in an aprotic solvent. The physical morphology of the hollow fiber membrane, i.e., the asymmetric microporous wall, is rapidly formed by passing the polymeric dope mixture through an outer annular orifice of a tube-in-orifice spinneret while simultaneously passing a precipitating solution through the central tube of the spinneret. The emerging hollow fiber travels substantially downward for about 0.01-10 m before submersion into a quenching bath. The asymmetrical, microporous, hollow fiber membrane is biocompatible and suitable for use in, for example, dialysis, hemodialysis, ultrafiltration, and water filtration applications.
    Type: Grant
    Filed: May 6, 1993
    Date of Patent: June 9, 1998
    Assignee: Minntech Corporation
    Inventors: Randal M. Wenthold, Robert T. Hall, II, Robert G. Andrus, Paul D. Brinda, Louis C. Cosentino, Robert F. Reggin, Daniel T. Pigott
  • Patent number: 5683584
    Abstract: An asymmetric, microporous hollow fiber membrane comprising a polyimide is disclosed. The hollow fiber membrane is chemically inert to aqueous solutions and/or blood, is immediately rewettable after repeated steam and chemical sterilizations, has superior clearance, sieving, and water permeability characteristics and is usable over a wide range of applications such as dialysis and water filtration. Also disclosed is the process for manufacturing the polyimide hollow fiber membrane.
    Type: Grant
    Filed: May 18, 1995
    Date of Patent: November 4, 1997
    Assignee: Minntech Corporation
    Inventors: Randal M. Wenthold, Robert T. Hall, II, Robert G. Andrus, Louis C. Cosentino
  • Patent number: 5605627
    Abstract: A dialysate filter including asymmetric, microporous, hollow fiber membranes incorporating a polyimide. The dialysate filter connects to the dialysis machine immediately before the dialyzer ensuring complete filtration of the dialysate, easy visual inspection, quick installation and removal, and easy disinfection of the filter.
    Type: Grant
    Filed: April 7, 1995
    Date of Patent: February 25, 1997
    Assignee: Minntech Corporation
    Inventors: Daniel B. Carlsen, Robert G. Andrus, Robert T. Hall, II
  • Patent number: RE36914
    Abstract: A dialysate filter including asymmetric, microporous, hollow fiber membranes incorporating a polyimide. The dialysate filter connects to the dialysis machine immediately before the dialyzer ensuring complete filtration of the dialysate, easy visual inspection, quick installation and removal, and easy disinfection of the filter.
    Type: Grant
    Filed: February 16, 1999
    Date of Patent: October 17, 2000
    Inventors: Daniel B. Carlsen, Robert G. Andrus, Robert T. Hall, II