Patents by Inventor Douglas D. Korthals

Douglas D. Korthals 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).

  • Convertible mower deck with mulch on demand actuator
    Patent number: 9750179
    Abstract: A convertible mower deck has a plurality of cutting chambers with a rotary cutting blade in each chamber and a side discharge opening from one of the cutting chambers, pivoting gates between the adjacent cutting chambers, and a pivoting side discharge door between a cutting chamber and the side discharge opening. Each of the gates and side discharge door are movable between a discharge or collection position and a mulching position. A mulch on demand actuator includes a switch in an operator station that causes a pivot control plate on a shaft to rotate and move linkages between the gates and door between the discharge or collection position and mulching position.
    Type: Grant
    Filed: May 8, 2013
    Date of Patent: September 5, 2017
    Assignee: DEERE & COMPANY
    Inventors: Douglas D. Korthals, Steven L. Dudzinski
  • CONVERTIBLE MOWER DECK WITH MULCH ON DEMAND ACTUATOR
    Publication number: 20140331634
    Abstract: A convertible mower deck has a plurality of cutting chambers with a rotary cutting blade in each chamber and a side discharge opening from one of the cutting chambers, pivoting gates between the adjacent cutting chambers, and a pivoting side discharge door between a cutting chamber and the side discharge opening. Each of the gates and side discharge door are movable between a discharge or collection position and a mulching position. A mulch on demand actuator includes a switch in an operator station that causes a pivot control plate on a shaft to rotate and move linkages between the gates and door between the discharge or collection position and mulching position.
    Type: Application
    Filed: May 8, 2013
    Publication date: November 13, 2014
    Applicant: Deere & Company
    Inventors: Douglas D. Korthals, Steven L. Dudzinski
  • Mowing machines with ergonomic hand control levers
    Patent number: 6868657
    Abstract: Hand control levers with ergonomic grip members. Such hand control levers are used on vehicles, preferably lever-operated mowing machines. The hand control levers can reduce anatomical stress, fatigue or discomfort experienced by users of such vehicles.
    Type: Grant
    Filed: May 15, 2002
    Date of Patent: March 22, 2005
    Assignee: Deere & Company
    Inventors: Brian E. Bauer, Ellis R. West, Douglas D. Korthals
  • Mowing machines with ergonomic hand control levers
    Publication number: 20030213219
    Abstract: The present invention relates to hand control levers with ergonomic grip members. Such hand control levers are used on vehicles, preferably lever-operated mowing machines. The hand control levers can reduce anatomical stress, fatigue or discomfort experienced by users of such vehicles.
    Type: Application
    Filed: May 15, 2002
    Publication date: November 20, 2003
    Inventors: Brian E. Bauer, Ellis R. West, Douglas D. Korthals