Patents by Inventor Fred O. Bohls

Fred O. Bohls 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: 5935095
    Abstract: An external slot valve for controlling blood flow through the outlet of a shunt of a cardiopulmonary bypass pump wherein a valve seat having a knife edge is fixedly connected to the fixed plate of the bypass pump, and a valve head having a knife edge is pivotally connected to the fixed plate. The valve head is spring biased to the closed position against the valve seat to pinch the shunt extending therethrough. When in the open position, the knife edges provide a slot forming a large orifice for the blood to flow through the outlet of the shunt to diminish the work of the pump and reduce trauma to the blood.
    Type: Grant
    Filed: August 14, 1997
    Date of Patent: August 10, 1999
    Inventor: Fred O. Bohls
  • Patent number: 5823930
    Abstract: A cam controlled pulsatile flow pump for neonatal and biventricular cardiac support systems wherein cylindrical cams having various profiles designed for a particular patient are selectively mounted on the output shaft of a motor. A roller follower engages the cam and is operatively connected to a compression plate under which at least one compressible conduit containing the patient's blood extends. The stroke volume of blood contained in the conduit can also be controlled.
    Type: Grant
    Filed: February 13, 1996
    Date of Patent: October 20, 1998
    Inventors: Thomas M. Runge, Fred O. Bohls
  • Patent number: 5383839
    Abstract: External inlet and outlet pinch-type plate valves for controlling the blood flow through a compressible shunt of a cardiopulmonary bypass pump wherein the valves are not fixedly connected to the compression chamber or housing of the pump so that the distance between the inlet and outlet valves can be adjusted to thereby allow adjustment of stroke volume to fit the needs of the patient being treated.
    Type: Grant
    Filed: August 10, 1993
    Date of Patent: January 24, 1995
    Assignee: Thomas M. Runge
    Inventor: Fred O. Bohls
  • Patent number: 4553532
    Abstract: To decrease hemolysis and reduce the cost of single use disposable tubing used during surgery, valve elements pivotally suspended in the bypass pump compression chamber respond to gravity and variations in fluid pressure within the shunt and act entirely on the exterior of the shunt to cyclically control blood flow therethrough. Interior valves for the shunt tubing are entirely eliminated.
    Type: Grant
    Filed: July 18, 1983
    Date of Patent: November 19, 1985
    Assignee: Thomas M. Runge
    Inventor: Fred O. Bohls