Patents by Inventor Richard D. Primdahl

Richard D. Primdahl 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: 5888381
    Abstract: A faucet mounted water filtration system with a filter life monitor includes a filter housing with a flexible cap which deflects upon introduction of water into the housing. The deflection of the cap closes a switch on an electrical circuit which counts the time the water is flowing through the housing. Once a predetermined amount of time accumulates, the circuit generates a message to inform the user that the filter needs replacement. The invention further includes a selector switch on the electrical circuit for signaling the circuit to count one of two predetermined amounts of time prior to generating a message.
    Type: Grant
    Filed: May 16, 1997
    Date of Patent: March 30, 1999
    Assignee: United States Filter Corporation
    Inventors: Richard D. Primdahl, Dale A. Squier, John Zabinski
  • Patent number: 5833849
    Abstract: A spout-mounted water filter assembly suitable for use with a shallow sink having a short necked spout. The water filter assembly includes a water filter unit and an extension pipe which provides additional vertical clearance between the base of the sink and the outlet of the filter unit. The extension pipe may further be dimensioned to provide additional clearance relative to an inner edge of the sink in order to prevent interference between the water filter unit and the sink. The water filter assembly of the present invention is versatile and may be configured in a variety of orientations to fit a variety of sink/faucet combinations.
    Type: Grant
    Filed: April 28, 1997
    Date of Patent: November 10, 1998
    Assignee: Everpure, Inc.
    Inventor: Richard D. Primdahl
  • Patent number: 5055086
    Abstract: A coin sorter having a rotatable disc includes a brake mechanism for stopping rotation of the disc in response to a predetermined number of counted coins. The disc is driven through a gear train by an electric motor. The brake mechanism includes a first brake mechanism coupled to the motor for stopping rotation thereof, a second brake mechanism coupled to the coin disc for stopping rotation thereof, and a control mechanism for operating the brake mechanisms in a synchronous manner so as to avoid any shock loads upon the gear train due to existence of torque differentials on either ends thereof. The brake mechanisms are adapted to have substantially identical stopping times and are operated in such a manner as to be energized in a substantially instantaneous manner when the braking sequence is initiated.
    Type: Grant
    Filed: February 5, 1990
    Date of Patent: October 8, 1991
    Assignee: Cummins-Allison Corporation
    Inventors: Donald E. Raterman, Richard D. Primdahl, Richard A. Mazur
  • Patent number: 4921463
    Abstract: A coin sorter having a rotatable disc includes a brake mechanism for stopping rotation of the disc in response to a predetermined number of counted coins. The disc is driven through a gear train by an electric motor. The brake mechanism includes an electromagnetic actuating assembly and an armature mounted on the shaft of a motor. Upon energization of the actuating assembly, the armature is drawn into contact with the actuating assembly to provide a braking pressure which halts rotation of the motor and the disc.
    Type: Grant
    Filed: October 27, 1987
    Date of Patent: May 1, 1990
    Assignee: Cummins-Allison Corporation
    Inventors: Richard D. Primdahl, Donald E. Raterman
  • Patent number: 4526204
    Abstract: A two lever, three function control apparatus for hydraulic control valves wherein a first control lever end is connected by a first cable to a first hydraulic valve operator, a link perpendicular to the first cable interconnects the first control lever and one leg of a bellcrank rotatable about on axis parallel to the first control lever. A second leg of the bellcrank disposed at right angles to the first leg is connected to a second cable parallel to the first cable which in turn connects to a second hydraulic operator. Fore-and-aft movement of the first control lever actuate only the first cable and hydraulic valve and transverse movement of the first control lever actuates only the second cable and hydraulic valve. To physically differentiate between the two function, the second bellcrank leg is twice the length of the first leg and a detent mechanism acting on the bellcrank hub is also provided. A second control lever is connected by a third cable to a third hydraulic control valve operator.
    Type: Grant
    Filed: May 17, 1982
    Date of Patent: July 2, 1985
    Assignee: Dresser Industries, Inc.
    Inventor: Richard D. Primdahl
  • Patent number: RE34934
    Abstract: A coin sorter having a rotatable disc includes a brake mechanism for stopping rotation of the disc in response to a predetermined number of counted coins. The disc is driven through a gear train by an electric motor. The brake mechanism includes a first brake mechanism coupled to the motor for stopping rotation thereof, a second brake mechanism coupled to the coin disc for stopping rotation thereof, and a control mechanism for operating the brake mechanisms in a synchronous manner so as to avoid any shock loads upon the gear train due to existence of torque differentials on either ends thereof. The brake mechanisms are adapted to have substantially identical stopping times and are operated in such a manner as to be energized in a substantially instantaneous manner when the braking sequence is initiated.
    Type: Grant
    Filed: October 6, 1993
    Date of Patent: May 9, 1995
    Inventors: Donald E. Raterman, Richard A. Mazur, Richard D. Primdahl