Patents by Inventor Dean Campbell

Dean Campbell 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).

  • Rotor blade lead-lag hydraulic damper with centrifugal force compensating damping characteristics
    Patent number: 11697492
    Abstract: A piston assembly for a lead-lag damper for a blade mounted on a rotor of a helicopter includes a piston-rod that has an inside surface and a piston-head that extends radially outward therefrom. The piston-rod has two ports extending therethrough on opposing sides of the piston-head. A sleeve is positioned in the piston-rod and has two annular passages that communicate with the respective ports. A valve spool is disposed in and slidingly engages the sleeve. The valve spool has a channel which is in variable fluid communication with two passages. The piston assembly includes a biasing member that biases the valve spool axially away from it. The channel has an axial width configured to variably regulate fluid flow between the two ports to control dampening of the piston-rod in response to centrifugal forces applied to the valve spool.
    Type: Grant
    Filed: April 8, 2021
    Date of Patent: July 11, 2023
    Assignee: Roller Bearing Company of America, Inc.
    Inventors: Mark Alger, Randall Kohuth, Dean Campbell
  • ROTOR BLADE LEAD-LAG HYDRAULIC DAMPER WITH CENTRIFUGAL FORCE COMPENSATING DAMPING CHARACTERISTICS
    Publication number: 20210316850
    Abstract: A piston assembly for a lead-lag damper for a blade mounted on a rotor of a helicopter includes a piston-rod that has an inside surface and a piston-head that extends radially outward therefrom. The piston-rod has two ports extending therethrough on opposing sides of the piston-head. A sleeve is positioned in the piston-rod and has two annular passages that communicate with the respective ports. A valve spool is disposed in and slidingly engages the sleeve. The valve spool has a channel which is in variable fluid communication with two passages. The piston assembly includes a biasing member that biases the valve spool axially away from it. The channel has an axial width configured to variably regulate fluid flow between the two ports to control dampening of the piston-rod in response to centrifugal forces applied to the valve spool.
    Type: Application
    Filed: April 8, 2021
    Publication date: October 14, 2021
    Applicant: Roller Bearing Company of America, Inc.
    Inventors: Mark Alger, Randall Kohuth, Dean Campbell