Patents by Inventor Donald E. Knoth

Donald E. Knoth 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: 5472412
    Abstract: An articulated knee brace includes a pair of arms pivotally connected by corresponding pivot pins and gear segments supported by a set of hub plates having holes for receiving adjustable stop pins. The arms are attached by flexible and releasable bands to a person's limb on opposite sides of a joint, and one of the arms carries an adjustable hydraulic control unit. The unit includes a tubular housing enclosing a pair of axially spaced pistons rigidly connected by a shaft, and a curved link member connects the pistons to the hub plates eccentrically of the pivot axes. A set of manually rotatable valves are supported by the housing between the pistons and variably control the flow of hydraulic fluid through the valves and between the piston chambers in response to pivoting of the arms for selectively and independently adjusting the resistance to flexion and extension of the brace and limb.
    Type: Grant
    Filed: April 5, 1994
    Date of Patent: December 5, 1995
    Assignee: Mauch Laboratories, Inc.
    Inventor: Donald E. Knoth
  • Patent number: 5443521
    Abstract: A prosthetic leg has a pivotal knee joint and a hydraulic fluid control unit connected to provide variable forces which dampen flexion and extension of the knee and also bias the leg to its extended position. The unit includes an aluminum housing lined with an axially adjustable sleeve and control bushing defining a cylindrical operating chamber which receives a piston mounted on a tubular piston rod. The housing and operating chamber receive hydraulic fluid or oil which flows during movement of the piston through fluid control ports, channels and adjustable gaps defined by the sleeve and bushing for damping the movement of the rod. The piston rod encloses a preferably sealed gas pressurized flexible bladder which forms an oil accumulator during inward movement of the piston rod into a displacement chamber and also produces variable forces for moving the piston rod outwardly to its extended position.
    Type: Grant
    Filed: December 30, 1993
    Date of Patent: August 22, 1995
    Assignee: Mauch Laboratories, Inc.
    Inventors: Donald E. Knoth, William L. Phillips
  • Patent number: 5405409
    Abstract: A prosthetic leg has a pivotal knee joint and a hydraulic fluid control unit connected to provide variable forces which dampen flexion and extension of the knee and also bias the leg to its extended position. The unit includes an aluminum housing lined with an axially adjustable sleeve and control bushing defining a cylindrical operating chamber which receives a piston mounted on a tubular piston rod. The housing and operating chamber receive hydraulic fluid or oil which flows during movement of the piston through fluid control ports, channels and adjustable gaps defined by the sleeve and bushing for damping the movement of the rod. The piston rod encloses a gas filled flexible bladder which forms an oil accumulator during inward movement of the piston rod into a displacement chamber and also produces variable forces for moving the piston rod outwardly to its extended position.
    Type: Grant
    Filed: January 21, 1994
    Date of Patent: April 11, 1995
    Inventor: Donald E. Knoth
  • Patent number: 5049039
    Abstract: A radial piston and cylinder compressed gas motor is disclosed which is particularly suited for use where economical power sources are required. The motor includes a cylinder block having a plurality of radially extending cylinders open at their outer ends to radially extending passages and having exhaust ports open when associated pistons are adjacent their bottom dead center positions. Such passages extend to a valve system provided on the crank of the motor which functions to supply compressed gas to selected cylinders while connecting other cylinders together so that gas is exhausted from cylinders containing extending pistons to open exhaust ports in other cylinders. This minimizes back pressure to resist motor operation. The crank is formed of two generally cylindrical members and can be produced without eccentric machining or grinding operations.
    Type: Grant
    Filed: November 30, 1989
    Date of Patent: September 17, 1991
    Assignee: Pneumotor, Inc.
    Inventors: Donald E. Knoth, James W. Bradbury, Mark A. Nagy