Patents by Inventor Thomas F. Christensen

Thomas F. Christensen 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: 7891477
    Abstract: A clutch assembly for an agricultural work vehicle having a piston slidably disposed within a chamber having a first portion and a second portion. The piston is positionable between a first position and a second position in response to a fluid pressure within the first portion of the chamber to actuate a clutch mechanism. A sealing ring is associated with the piston to substantially prevent flow of fluid between the first portion and the second portion when the piston is in the first position. A bleed assembly is configured to permit flow of fluid between the first portion and the second portion when the piston is in the first position. The bleed assembly allows sufficient flow to substantially prevent unintentional engagement of the clutch mechanism.
    Type: Grant
    Filed: March 23, 2007
    Date of Patent: February 22, 2011
    Assignee: CNH America LLC
    Inventors: Thomas F. Christensen, Richard A. Miller, Benjamin L. McCash
  • Publication number: 20080093195
    Abstract: A clutch assembly for an agricultural work vehicle having a piston slidably disposed within a chamber having a first portion and a second portion. The piston is positionable between a first position and a second position in response to a fluid pressure within the first portion of the chamber to actuate a clutch mechanism. A sealing ring is associated with the piston to substantially prevent flow of fluid between the first portion and the second portion when the piston is in the first position. A bleed assembly is configured to permit flow of fluid between the first portion and the second portion when the piston is in the first position. The bleed assembly allows sufficient flow to substantially prevent unintentional engagement of the clutch mechanism.
    Type: Application
    Filed: March 23, 2007
    Publication date: April 24, 2008
    Applicant: CNH America LLC
    Inventors: Thomas F. Christensen, Richard A. Miller, Benjamin L. McCash
  • Patent number: 5791447
    Abstract: A clutch structure is provided that automatically compensates for manufacturing or part-to-part tolerance variations in new clutches and that continuously compensates for wear of interleaved clutch plates throughout the life of the clutch. The clutch includes an actuator, preferably a fluid piston, that compresses the clutch plates to engage the clutch and transmit power between two rotating elements. An adjustment ring, fitted to an actuating ring, is contacted by a portion of the piston and is displaced against the force of a biasing spring during engagement of the clutch. Abutment members limit movement of the actuating ring, permitting the piston to displace the adjustment ring unidirectionally on the actuating ring during full engagement of the clutch. Upon disengagement of the clutch, the biasing spring urges the actuating ring, and with it the adjustment ring, back to its disengaged position. The adjustment ring thereby urges the piston to a reference disengaged position.
    Type: Grant
    Filed: August 21, 1996
    Date of Patent: August 11, 1998
    Assignee: Case Corporation
    Inventors: Anthony J. Lamela, Thomas F. Christensen
  • Patent number: 5186284
    Abstract: A fail safe self-adjusting brake is disclosed in which a service piston selectively actuates brake discs to contact shaft discs and apply braking to the shaft. The service piston is hydraulically actuated. Should there be a system failure an emergency piston forces the service piston to brake shaft rotation. The service and emergency pistons are uniquely mounted such that they are properly guided within the brake housing. In a further feature of the present invention, the location of the brake discs relative to the shaft discs is adjustable to vary the amount of movement necessary to cause braking. This adjustment allows the brake discs to move relative to the housing to accommodate wear on the brake or shaft discs. A gage is mounted within the housing to monitor the amount of adjustment of the brake discs, and thus to give an indication of the wear on those discs.
    Type: Grant
    Filed: May 31, 1991
    Date of Patent: February 16, 1993
    Assignee: Case Corporation
    Inventors: Anthony J. Lamela, Thomas F. Christensen, David T. Rach