Patents by Inventor Casper J. N. Rekers

Casper J. N. Rekers 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: 6251275
    Abstract: A membrane filtration module, comprising a housing, a semi-permeable membrane, which is accommodated in the housing and has a liquid side for the introduction of liquid to be filtered and a concentrate side opposite the liquid side, as well as a permeate chamber, which surrounds the membrane and is in communication with a permeate-discharge line for discharging permeate. According to the invention, the wall of the housing comprises one or more channels which are closed towards the liquid side and the concentrate side and are in communication with the permeate chamber. These channels act as a permeate discharge.
    Type: Grant
    Filed: March 3, 1998
    Date of Patent: June 26, 2001
    Assignee: X-Flow B.V.
    Inventor: Casper J. N. Rekers
  • Patent number: 5833854
    Abstract: The invention relates to a semipermeable composite membrane comprising a microporous substrate provided with a semipermeable microporous substrate membrane which is provided, on at least one side, with a water-permeable polymer layer, said polymer layer containing the interfacial-polymerization product of an amine-terminal dendrimer and a compound polymerizing therewith. According to the invention, the amine-terminal dendrimers used, are poly(alkylene imine) dendrimers. These dendrimers preferably have terminal primary and/or secondary amine groups. In particular, use is made of a 1,4-diaminobutane ?4!: (1-azabutylidene).sup.x-4 : propylamine or propyl-N-alkyl-amine, wherein x=4, 8, 16, 32 or 64. Expediently, the compound which polymerizes with the dendrimer is selected from the group consisting of a carboxylic acid or carboxylic acid derivative, a sulphonic acid or sulphonic acid derivative, and an isocyanate compound.
    Type: Grant
    Filed: December 17, 1996
    Date of Patent: November 10, 1998
    Assignee: Stork Friesland BV
    Inventors: Arie Zwijnenburg, Jan Willem De Rijk, Casper J. N. Rekers
  • Patent number: 5494577
    Abstract: An apparatus is described for treating polluted water. The apparatus comprises a supply system for polluted water; an activated-sludge reactor; one or more filter membrane modules; an air supply system and a discharge system for the treated water. The filter membrane modules comprise hollow membranes within a casing. Said filter membrane modules on one side adjoin the activated-sludge reactor and on the other side adjoin air distribution means. The activated-sludge reactor communicates, via a bypass line, with a sludge receiving container which adjoins the air distribution means. The apparatus functions in such a way that the water to be treated and air supplied are flowing in the same direction through the hollow membranes, the permeate flowing through the membranes towards the space between the casing and the membranes, where it is discharged via permeate discharge system.
    Type: Grant
    Filed: December 21, 1994
    Date of Patent: February 27, 1996
    Assignee: Stork Friesland B.V.
    Inventor: Casper J. N. Rekers
  • Patent number: 5382210
    Abstract: A rowing simulator which provides an oarsman with realistic resistance, motion, and feel. A curved frame supports and guides a freely sliding seat and a freely sliding energy dissipation unit. An oarsman, positioned on the seat, places his or her feet on a footrest that is part of the energy dissipating unit and pulls on a handle that simulates an oar. A chain connected to the handle causes a geared, resistance-producing flywheel to spin and a take-up device, having a series of pulleys and an elastic element, controls chain tension. During exercise, the independent seat and energy dissipating unit move apart and then together in a coordinated manner as a function of the stroke cycle of the oarsman. The curvature of the frame allows gravity to keep the oarsman in a central portion of the frame.
    Type: Grant
    Filed: November 13, 1992
    Date of Patent: January 17, 1995
    Inventor: Casper J. N. Rekers
  • Patent number: 5122273
    Abstract: A membrane for membrane filtration is disclosed, comprising a polymer matrix formed by coagulation with a liquid coagulant from a casting syrup, which polymer matrix is linked to hydrophilic groups belonging to a compound which has a hydrophilic chain section, is not coagulated by the liquid coagulant, is coupled on either side to a hydrophobic chain, is anchored in the polymer matrix by non-chemical bonding, and is composed of a compound which has a molecular weight of at least 2000 and can be used as a thickening agent.
    Type: Grant
    Filed: February 8, 1991
    Date of Patent: June 16, 1992
    Assignee: Stork Friesland B. V.
    Inventors: Casper J. N. Rekers, Gerrit J. Snijders, Arie Zwijnenburg, Dirk C. Weyenberg