Patents by Inventor Christopher C. Day

Christopher C. Day 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: 4877051
    Abstract: A fluid flow control apparatus including a fluid flow control valve, a fluid flow sensor, and a fluid flow control circuit receiving a signal from the fluid flow sensor and outputting a signal to the fluid flow control valve. The fluid flow control circuit including an actual control circuit which outputs a signal related to the comparison of an actual flow signal and a desired flow signal, a desired flow comparator circuit which outputs a signal based on the comparison of the desired flow signal with a desired flow threshold signal, and a summing circuit which receives the outputs and provides a control signal based on these outputs.
    Type: Grant
    Filed: November 28, 1988
    Date of Patent: October 31, 1989
    Assignee: MKS Instruments, Inc.
    Inventor: Christopher C. Day
  • Patent number: 4571547
    Abstract: Signals subject to amplitude variations, such as physiological signals, are detected when the amplitude thereof exceeds a threshold level, where the threshold level is made adaptive to both the amplitude and the rate of the signals so as to desensitize the detection process for artifacts, which occur sporadically, and to avoid the need for automatic gain control of the signals prior to detection.
    Type: Grant
    Filed: June 27, 1983
    Date of Patent: February 18, 1986
    Assignee: Clinical Data Inc.
    Inventor: Christopher C. Day
  • Patent number: 4187858
    Abstract: In apparatus such as a defibrillator having a CRT display of an ECG wave, and an alternative display of the firing time of the defibrillator pulse in relation to the ECG wave, the inclusion of method and apparatus for orienting the waveform to a synchronization indicator. In the preferred form, the display is a single, non-fade stationary complex of the ECG wave starting prior to the occurrence of the oriented "P" wave. The display is timed through combination of clocking pulses responsive to a wave detection apparatus and a recirculating memory which establishes an orienting marker. The clock pulsing includes a predetermined delay to initiation of display from the data recirculating memory such that the data display is coordinated in time to a fixed reference.
    Type: Grant
    Filed: April 17, 1978
    Date of Patent: February 12, 1980
    Assignee: American Optical Corporation
    Inventors: Christopher C. Day, Robert A. McEachern
  • Patent number: 4137907
    Abstract: Improved method and apparatus for identifying and quantizing a substantially periodic, steeply rising wavefront of a signal in the possible presence of low amplitude interference. A time derivative of at least the steep wavefront is obtained. The derivative is then integrated over a predetermined interval in each of successive repetitions of the steep wavefront, the interval being that during which the derivative exceeds a reference level. A threshold value is established, preferably dynamically, to verify or validate that when the derivative exceeds the reference level it indeed represents the steeply rising wavefront. The integrated derivative is recognized as the quantized value of the steeply rising wavefront only if such verification occurs. The invention is suited to oscillometric determination of systolic pressure in a patient, where measurement of signal amplitude is preferably achieved by integrating the time derivative of the systolic rise wavefront.
    Type: Grant
    Filed: December 27, 1976
    Date of Patent: February 6, 1979
    Assignee: American Optical Corporation
    Inventors: William D. Jansen, Jerry D. Haney, Christopher C. Day, Stephen A. Schneeberger