Abstract: Apparatus for non-invasive measuring of the sound velocity of a fluid flowing in a tubing having a small internal diameter for the fluid passage as compared to the tubing wall thickness and having points of two different and known transverse length with a sensor mounted at each point and a delay line adjacent to the tubing at each point. Each sensor is connected to a circuit that provides ultrasonic energy signals that are transmitted through the tubing walls, the flowing fluid and the delay line to be reflected back to the sensor from which the round trip transit time of the signals is measured and the sound velocity calculated from the two measured round trip transit times and the differential between the known transverse lengths.
Abstract: Apparatus for determining the sound velocity of a liquid in a specimen having two walls between which the liquid is contained with one of the walls being deformable has a sensor including a transducer for transmitting ultrasonic energy signals between the specimen walls and apparatus for deforming the specimen wall by a known distance from a first to a second position relatively spaced from the transducer and an electronic circuit including a microprocessor for measuring first and second transit times of the signals through the liquid between the specimen walls for each of the specimen deformable wall first and second positions, and for calculating the sound velocity of the liquid based upon the known distance and the two measured transit times. Where blood is the liquid values of parameters such as glucose and hematocrit are obtained based on algorithms pre-programmed in the microprocessor.
Abstract: Apparatus and method for non-invasive measuring of the sound velocity of a fluid, such as a liquid, flowing in a tubing having points of two different and known transverse length has one sensor mounted at each point connected to a circuit that provides signals to each sensor that are returned to it after passing through the tubing wall and flowing fluid and reflection from the tubing internal wall opposing each sensor and from which the round trip transit time of the signals is measured and the sound velocity calculated from the two measured round trip transit times and the differential between the known transverse lengths. Flexible tubing is placed in the slot of a measuring head which deforms it to provide the two points at one location or the slot has two sections of different transverse length along its length with a point at each section.
Abstract: Apparatus for determining the sound velocity of a liquid in a specimen having two walls between which the liquid is contained with one of the walls being deformable has a sensor including a transducer for transmitting ultrasonic energy signals between the specimen walls and apparatus for deforming the specimen wall by a known distance from a first to a second position relatively spaced from the transducer and an electronic circuit including a microprocessor for measuring first and second transit times of the signals through the liquid between the specimen walls for each of the specimen deformable wall first and second positions, and for calculating the sound velocity of the liquid based upon the known distance and the two measured transit times. Where blood is the liquid values of parameters such as glucose and hematocrit are obtained based on algorithms pre-programmed in the microprocessor.
Abstract: Apparatus for non-invasive measuring of the sound velocity of a fluid flowing in a tubing having a small internal diameter for the fluid passage as compared to the tubing wall thickness and having points of two different and known transverse length with a sensor mounted at each point and a delay line adjacent to the tubing at each point. Each sensor is connected to a circuit that provides ultrasonic energy signals that are transmitted through the tubing walls, the flowing fluid and the delay line to be reflected back to the sensor from which the round trip transit time of the signals is measured and the sound velocity calculated from the two measured round trip transit times and the differential between the known transverse lengths.
Abstract: A method and apparatus for measuring the sound velocity of a flowing fluid includes a cartridge having a hollow interior through which the fluid flows formed by first and second chambers of different diameters that define first and second walls extending toward the cartridge longitudinal axis from which energy transmitted by a single sensor mounted in the cartridge is reflected back to the sensor. An electronic circuit includes a microprocessor that is programmed with the distance between the first and second walls and that measures the round-trip transit time of the signal energy transmitted to and reflected from each of the first and second walls and calculates the sound velocity of flowing fluid using the two measured round trip transit times and the programmed value of the fixed distance between the walls.