A method and a device for ascertaining a fluid injection quantity of an injection system. The injection system includes a high-pressure pump, a high-pressure region that adjoins the high-pressure pump, a pressure sensor, and an injector that is fed from the high-pressure region. The method includes detecting a measurement signal using the pressure sensor and segmenting a first pressure profile from the measurement signal. The first pressure profile characterizes the pressure profile prior to a fluid injection using the injector. The method also includes segmenting a second pressure profile from the measurement signal. The second pressure profile characterizes the pressure profile after the fluid injection using the injector. The method also includes performing a core density estimation using the first pressure profile and the second pressure profile, ascertaining a pressure difference, and ascertaining the fluid injection quantity using the pressure difference.

A method includes receiving, by a processor of a dialysis machine, a dialysate flow rate, a bicarbonate setting value, a signal from a pressure sensor configured to measure a pressure within a container, and a signal indicating a state of a fill valve; determining, based on the signal received from the pressure sensor and the state of the fill valve, fill parameters; determining a volume of the container based on at least two of the fill parameters; determining a depletion time in which the concentrate will be depleted from the container based on the volume of the container, the dialysate flow rate, and the bicarbonate setting value; determining, based on the depletion time, an amount of time remaining before the concentrate will be depleted from the container; and causing the dialysis machine to indicate the amount of time remaining before the concentrate will be depleted from the container.

A method includes receiving, by a processor of a dialysis machine, a dialysate flow rate, a bicarbonate setting value, a signal from a pressure sensor configured to measure a pressure within a container, and a signal indicating a state of a fill valve; determining, based on the signal received from the pressure sensor and the state of the fill valve, fill parameters; determining a volume of the container based on at least two of the fill parameters; determining a depletion time in which the concentrate will be depleted from the container based on the volume of the container, the dialysate flow rate, and the bicarbonate setting value; determining, based on the depletion time, an amount of time remaining before the concentrate will be depleted from the container; and causing the dialysis machine to indicate the amount of time remaining before the concentrate will be depleted from the container.

A method and apparatus is disclosed for measuring the volume of fluid in a variable volume vessel.

A method and apparatus is disclosed for measuring the volume of fluid in a variable volume vessel.

A sensor includes a body member, a volume change body, and a detection member. The body member has a flat plate-like shape, a first end in a first direction being supported, and a storage space opening at at least one of both end faces in a thickness direction. The volume change body, whose volume changes depending on an amount of a target, is supported by the body member so that at least a part of the volume change body is stored in the storage space. The detection member is in contact with a second end in the first direction of the body member, and detects stress caused by the change in the volume of the volume change body.

A sensor includes a body member, a volume change body, and a detection member. The body member has a flat plate-like shape, a first end in a first direction being supported, and a storage space opening at at least one of both end faces in a thickness direction. The volume change body, whose volume changes depending on an amount of a target, is supported by the body member so that at least a part of the volume change body is stored in the storage space. The detection member is in contact with a second end in the first direction of the body member, and detects stress caused by the change in the volume of the volume change body.

Acoustic volume indicators for determining liquid or gas volume within a container comprise a contactor to vibrate a container wall, a detector to receive vibration data from the container wall, a processor to convert vibration data to frequency information and compare the frequency information to characteristic container frequency vs. volume data to obtain the measured volume, and an indicator for displaying the measured volume. The processor may comprise a microprocessor disposed within a housing having lights that each represent a particular volume. The microprocessor is calibrated to provide an output signal to a light that indicates the container volume. The processor may comprise a computer and computer program that converts the data to frequency information, analyzes the frequency information to identify a peak frequency, compares the peak frequency to the characteristic frequency vs. volume data to determine the measured volume, and displays the measured volume on a video monitor.

An acoustic volume sensing device is disclosed. The device includes a housing comprising a reference volume chamber and a variable volume chamber, the reference volume chamber and the variable volume chamber connected by a resonant port, a first MEMS microphone located in acoustic relation to the variable volume chamber, a second MEMS microphone located in acoustic relation to the reference volume chamber, a MEMS speaker located in acoustic relation to the reference volume chamber, and a circuit board in electric connection with the first and second MEMS microphones and the MEMS speaker.

An acoustic volume sensing device is disclosed. The device includes a housing comprising a reference volume chamber and a variable volume chamber, the reference volume chamber and the variable volume chamber connected by a resonant port, a first MEMS microphone located in acoustic relation to the variable volume chamber, a second MEMS microphone located in acoustic relation to the reference volume chamber, a MEMS speaker located in acoustic relation to the reference volume chamber, and a circuit board in electric connection with the first and second MEMS microphones and the MEMS speaker.