Patents by Inventor Charles L. Davis

Charles L. Davis 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).

  • Publication number: 20160022151
    Abstract: Methods of obtaining physiological parameters of a body fluid compartment.
    Type: Application
    Filed: March 15, 2014
    Publication date: January 28, 2016
    Inventor: Charles L. DAVIS
  • Patent number: 7011631
    Abstract: Apparatus and methods for noninvasively measuring blood density and hematocrit in a human subject can include an appliance for applying pressure around a segment of a subject's limb or appendage that includes a pressure sensing means and encloses an array of impedance sensing devices applied to the subject's skin for independent fluid volume measurements. While applying pressure to the limb segment by the pressure appliance, measurements of blood pressure, blood pulse wave velocity, and limb segment impedance are recorded. The measurements are subsequently processed to yield changes of arterial blood volume during pulse wave passage. Then pressure, wave velocity, and derived volume data are combined to yield the density of the blood. Blood density is converted to hematocrit by means of a linear relationship between the two. Independent of the blood hematocrit, such apparatus and means may also be used to measure the density of enclosed fluid in other pulsed flow non-rigid wall vessel systems.
    Type: Grant
    Filed: January 20, 2004
    Date of Patent: March 14, 2006
    Assignee: Hemonix, Inc.
    Inventors: Charles L. Davis, Patrick D. Harrison, John E. Bronson
  • Publication number: 20040249292
    Abstract: Apparatus and methods for noninvasively measuring blood density and hematocrit in a human subject can include an appliance for applying pressure around a segment of a subject's limb or appendage that includes a pressure sensing means and encloses an array of impedance sensing devices applied to the subject's skin for independent fluid volume measurements. While applying pressure to the limb segment by the pressure appliance, measurements of blood pressure, blood pulse wave velocity, and limb segment impedance are recorded. The measurements are subsequently processed to yield changes of arterial blood volume during pulse wave passage. Then pressure, wave velocity, and derived volume data are combined to yield the density of the blood. Blood density is converted to hematocrit by means of a linear relationship between the two. Independent of the blood hematocrit, such apparatus and means may also be used to measure the density of enclosed fluid in other pulsed flow non-rigid wall vessel systems.
    Type: Application
    Filed: January 20, 2004
    Publication date: December 9, 2004
    Inventors: Charles L. Davis, Patrick D. Harrison, John E. Bronson
  • Patent number: 6749567
    Abstract: The present invention provides means and methods for noninvasively identifying the blood pressure characteristics in each of the seven types of vessels in the circulatory system, including the central venous pressure (CVP) through a single monitoring system using fluid depletion plethysmography. Known pressure is applied to a body region in increasing amounts to force blood volume from the body region in step-wise fashion through each vessel type. Blood volume depletion for each vessel type is measured by the increasing electrical impedance of the body part during depletion and is plotted against the increasing pressure data. The resulting series of slope changes within the plotted curve reveals the blood pressure for each vessel type. The data obtained may further be used to determine vessel wall compliance/tension as well as standard measurements such as pulse and large artery systolic and diastolic pressure.
    Type: Grant
    Filed: May 9, 2002
    Date of Patent: June 15, 2004
    Assignee: Hemonix, Inc.
    Inventors: Charles L. Davis, Patrick D. Harrison
  • Publication number: 20020188206
    Abstract: The present invention provides means and methods for noninvasively identifying the blood pressure characteristics in each of the seven types of vessels in the circulatory system, including the central venous pressure (CVP) through a single monitoring system using fluid depletion plethysmography. Known pressure is applied to a body region in increasing amounts to force blood volume from the body region in step-wise fashion through each vessel type. Blood volume depletion for each vessel type is measured by the increasing electrical impedance of the body part during depletion and is plotted against the increasing pressure data. The resulting series of slope changes within the plotted curve reveals the blood pressure for each vessel type. The data obtained may further be used to determine vessel wall compliance/tension as well as standard measurements such as pulse and large artery systolic and diastolic pressure.
    Type: Application
    Filed: May 9, 2002
    Publication date: December 12, 2002
    Inventors: Charles L. Davis, Patrick D. Harrison
  • Patent number: 5692513
    Abstract: Noninvasive-blood-pressure (NIBP) monitoring apparatus is disclosed which is usable to perform either oscillometric or auscultatory NIBP. The apparatus includes relatively adjustable, noninflatable, pressure-information-providing (PIP) structure usable to apply NIBP-useful pressure to such limb adjacent such vessel. Also included is pressure-changer structure associated with the PIP structure, and operable to adjust the same to a beginning NIBP-useful pressure, and to subsequent NIBP-useful pressures, with such adjustment effecting the availability of pressure information that can be sensed by such sensor structure. The apparatus is preferably constructed for oscillometric NIBP monitoring and includes a reaction band removably fittable on and circumscribingly about the limb of such living subject. The preferred construction is for portable, self-contained, ambulatory usage.
    Type: Grant
    Filed: September 30, 1994
    Date of Patent: December 2, 1997
    Assignee: Protocol Systems, Inc.
    Inventors: Charles L. Davis, John R. Marshall
  • Patent number: 5544661
    Abstract: A patient monitoring system which includes a portable device and a central station. The portable device includes an ECG and a photo-plethysmograph connected to the patient; arrhythmia analysis apparatus; an expert system for determining if a pre-established critical parameter set has been exceeded; and a wireless wide area communication device for automatically contacting the central station via a public cellular phone network when the critical parameter set has been exceeded. When the central station is contacted, the patient's ECG waveforms, measurements, and trends, are sent to the central monitoring station and a two way voice channel between the patient and the central station is automatically opened.
    Type: Grant
    Filed: January 13, 1994
    Date of Patent: August 13, 1996
    Assignee: Charles L. Davis
    Inventors: Charles L. Davis, Paul V. Long
  • Patent number: 5351694
    Abstract: Noninvasive-blood-pressure (NIBP) monitoring apparatus is disclosed which is usable to perform either oscillometric or auscultatory NIBP. The apparatus includes relatively adjustable, noninflatable, pressure-information-providing (PIP) structure usable to apply NIBP-useful pressure to such limb adjacent such vessel. Also included is pressure-changer structure associated with the PIP structure, and operable to adjust the same to a beginning NIBP-useful pressure, and to subsequent NIBP-useful pressures, with such adjustment effecting the availability of pressure information that can be sensed by such sensor structure. The apparatus is preferably constructed for oscillometric NIBP monitoring and includes a reaction band removably fittable on and circumscribingly about the limb of such living subject. The preferred construction is for portable, self-contained, ambulatory usage.
    Type: Grant
    Filed: November 16, 1992
    Date of Patent: October 4, 1994
    Assignee: Protocol Systems, Inc.
    Inventors: Charles L. Davis, John R. Marshall
  • Patent number: 5209615
    Abstract: An improved support mechanism for supporting a boring bar at spaced locations along its length within a workpiece during a boring operation, the present support mechanism being particularly adaptable for precision in-line boring of the cam shaft bores associated with overhead cam cylinder heads such as the Ford Escort overhead cylinder head presently in use and being specifically directed to centrally supporting the boring bar intermediate the respective opposite end portions of the cylinder head or other workpiece, the present support mechanism including a first annular member slidably positionable on the boring bar at an intermediate location along its length, the annular member being constructed to enable the boring bar to rotate freely therein, a second member slidably positionable within any one of the lifter bores associated with the particular cylinder head or other workpiece to be re-bored, the second member including a locking mechanism for locking the second member within any one of the lifter bores
    Type: Grant
    Filed: April 14, 1992
    Date of Patent: May 11, 1993
    Assignee: Sunnen Products Company
    Inventor: Charles L. Davis
  • Patent number: 5077488
    Abstract: A digital circuit both provides multiphasic timing signals and regulates the operating voltage of a non-ideal power source. In one embodiment, a delay line is provided whose delay characteristics vary inversely with operating voltage. Control gates are connected to selected outputs of the delay line to receive at differing times a control signal propagated through the delay line. In a preferred embodiment the control gates generate output signals the duration of which are determined by the delay characteristics of the delay line (and thus by the level of the operating voltage), such that the output signal duration increases in response to increases in operating voltage. The output signals activate current sinks or loads which increase the current drain on the non-ideal power source, thereby depressing its voltage.
    Type: Grant
    Filed: March 3, 1989
    Date of Patent: December 31, 1991
    Assignee: Abbott Laboratories
    Inventor: Charles L. Davis
  • Patent number: 5001417
    Abstract: Apparatus for measuring electrolyute concentrations in fluid samples. The apparatus includes an ion selective electrode having a plurality of ion selective detection sites. Each site has an affinity for a preselected electrolyte of interest and generates a potential having a magnitude related to the concentration of the corresponding electrolyte in the sample. A voltage to optical transducer circuit is provided to convert the voltage differentials to optical signals having intensity related to the concentration of the electrolytes in a first embodiment, a digital code related to the concentration of the electrolytes in a second embodiment, and an optical absorption or density value related to the concentration of the electrolytes in a third embodiment. The optical signals are suitable for detection by conventional optical detector apparatus of assay instruments and may be processed using conventional two point linear interpolation techniques to determine the concentrations of the preselected electrolytes.
    Type: Grant
    Filed: May 25, 1988
    Date of Patent: March 19, 1991
    Assignee: Abbott Laboratories
    Inventors: John G. Pumphery, Benton A. Durley, III, Paul E. Garrett, Edward G. Pumphrey, Charles L. Davis, Frederic L. Clark, Lawrence Spritzer
  • Patent number: 4981631
    Abstract: This invention relates to a process for making a lightweight article which involves the steps of: (1) feeding a thermoplastic resin composition into an extruder, wherein the thermoplastic resin composition contains (a) from about 94 to about 99 weight percent polyethylene terephthalate, and (b) from about 1 to about 6 weight percent of at least one polyolefin; (2) mixing an inert gas into the thermoplastic resin composition in the extruder while the thermoplastic resin composition is in the molten state; (3) extruding the thermoplastic resin composition containing the inert gas through a sheet forming die to produce a substantially amorphous cellular sheet which contains a sufficient amount of inert gas cells to provide the cellular sheet with a density which is within the range of about 0.4 to about 1.25; and (4) thermoforming the cellular sheet in a heated mold to produce the lightweight article. Dual-ovenable trays and other types of food containers can be made utilizing the process of this invention.
    Type: Grant
    Filed: March 31, 1989
    Date of Patent: January 1, 1991
    Assignee: The Goodyear Tire & Rubber Company
    Inventors: Tak M. Cheung, Charles L. Davis, Jack E. Prince
  • Patent number: 4952076
    Abstract: A film squeeze damper for a thrust bearing includes a plurality of curved beam segments each having a fluid chamber adjacent the support housing and mounted end to end to surround the thrust bearing. Side mounted nibs transmit the thrust load from a radial dependent member of the outer race to the support housing through each segment. This permits unrestrained radial damping of vibratory energy occasioned by the unbalance in the supported shaft. A mechanical stop is provided by the design to limit radial deflection of the segment during a high rotor unbalance.
    Type: Grant
    Filed: July 21, 1989
    Date of Patent: August 28, 1990
    Assignee: United Technologies Corporation
    Inventors: Walter H. Wiley, III, Charles D. Aaron, Jr., Russell L. Carlson, Charles L. Davis, III, Ronald A. Marmol
  • Patent number: 4949710
    Abstract: For use in performing non-invasive blood-pressure measurement (NIBP), an artifact rejection method for predicting expected data values from acquired data, and for adjusting previously acquired data based on the relationship of actually measured data values to their corresponding predicted values. The method is practiced in a system comprising an inflatable, occluding cuff, a pump and a valve coupled to the cuff, and monitoring apparatus coupled to the cuff adapted to measure cuff pressure and recurring blood-pressure pulsations occurring in the cuff that are caused by each heart contraction occurring in a measurement cycle. Cuff pressure is raised to a level above the patient's systolic pressure, and progressively reduced in a stepwise fashion to an ending cuff pressure. A fixed number of pulsations are measured and processed at a first and second cuff-pressure step, and a generally lesser number of pulsations are measured and processed at a third and subsequent cuff-pressure steps.
    Type: Grant
    Filed: October 6, 1988
    Date of Patent: August 21, 1990
    Assignee: Protocol Systems, Inc.
    Inventors: Thomas J. Dorsett, Charles L. Davis
  • Patent number: 4941201
    Abstract: An electronic data storage, transmission and retrieval apparatus and method wherein a combination power and data signal is received by a preferably portable and miniature data storage means which in turn modulates the combination signal in acordance with available data signals. Substantially simultaneous and bi-directional data communication can be achieved between a data link means and a data storage means without physical contact between the devices.
    Type: Grant
    Filed: April 4, 1989
    Date of Patent: July 10, 1990
    Assignee: Abbott Laboratories
    Inventor: Charles L. Davis
  • Patent number: 4889133
    Abstract: A microprocessor-controlled, oscillometric method for determining a patient's systolic, diastolic, and mean arterial pressure, practiced in a system comprising an inflatable, occluding cuff, a pump and a valve coupled to the cuff, and monitoring apparatus coupled to the cuff adapted to measure cuff pressure and recurring blood-pressure pulsations occurring in the cuff that are caused by each heart contraction occurring in a measurement cycle. Cuff pressure is raised to a level above the patinet's systolic pressure, and progressively reduced in a stepwise fashion to an ending cuff pressure. A fixed number of pulsations are measured and processed at a first and second cuff-pressure step, and a generally lesser number of oscillations are measured and processed at a third and subsequent cuff-pressure steps. The method includes a first artifact rejection technique used to check for false data relative to the formation of each blood-pressure pulsation.
    Type: Grant
    Filed: May 25, 1988
    Date of Patent: December 26, 1989
    Assignee: Protocol Systems, Inc.
    Inventors: Craig H. Nelson, Thomas J. Dorsett, Charles L. Davis
  • Patent number: 4796302
    Abstract: A finger and thumb protector is provided and consists of a pair of sheaths pivotly hinged towards each other. The sheaths have depressions on inner sides thereof to grip a nail thus allowing a person to hammer the nail with the sheaths cushioning the blows from the hammer.
    Type: Grant
    Filed: November 2, 1987
    Date of Patent: January 10, 1989
    Inventors: Charles L. Davis, George Spector
  • Patent number: 4771429
    Abstract: A circuit is disclosed which combines the functions of a cyclic redundancy check code (CRCC) generator and a pseudo-random number generator in such a way that common elements are shared rather than duplicated. A 16-stage shift register and two linear feedback paths are included for the CRCC and pseudo-random number generators. A control section of the circuit controls the mode of operation of the circuit according to the state of a mode control signal. A signal on a clear line resets the shift register or initializes it with a selected value depending on the state of the mode control signal. The mode control signal also controls the input of data on a data line and the output of generated CRC and pseudo-random access codes on output lines.
    Type: Grant
    Filed: September 18, 1986
    Date of Patent: September 13, 1988
    Assignee: Abbott Laboratories
    Inventors: Charles L. Davis, Jerry R. Sanders, James A. Rench
  • Patent number: 4747181
    Abstract: A door retainer for removably mounting on the folding steps of a recreational vehicle to prevent the door from opening, which door retainer is characterized by a flat step plate designed to fit on the top step of the folding steps and provided with a downwardly-extending rear plate for engaging the rear edge of the top step. A post is upward-standing from the step plate in close proximity to the door, in order to prevent the door from opening when the step plate and the rear plate are installed on the steps in functional position. A latch bracket projects downwardly from fixed attachment to the step plate and a tab slot is provided in the rear plate opposite the latch bracket for receiving a tab located on one end of a keeper plate. The opposite end of the keeper plate is fitted with a keeper bracket for engaging the latch bracket on the step plate and receiving the hasp of a padlock to secure the step plate and the rear plate in functional configuration on the folding steps of the recreational vehicle.
    Type: Grant
    Filed: June 18, 1987
    Date of Patent: May 31, 1988
    Inventor: Charles L. Davis
  • Patent number: 4700841
    Abstract: A method and configuration for packing flexible, flat packages in a carton for easy removal includes stacking the packages in a stack which has a height that is less than its length or width, placing the stack in a plastic bag within the carton on edge so that the stack fits loosely between the sides of the carton, and rotating the plastic bag and stack so that the packages lay flat in the carton and the neck of the plastic bag wraps around the stack.
    Type: Grant
    Filed: April 4, 1986
    Date of Patent: October 20, 1987
    Assignee: Kimberly-Clark Corporation
    Inventors: Lonnie W. Padgett, Jr., Charles L. Davis