Disclosed herein are a device and method designed for determining the liquid level in a container through measuring the pressure in the liquid by a pressure sensor located at the bottom of the container within a chamber designed to prevent solid particles dispersed in the liquid from reaching the sensor. Measuring the pressure of the liquid in the container can be based on an upper chamber located above a lower chamber, both adjacent chambers are located within a container. The upper chamber comprises tiny slots allowing the liquid in the container to enter the upper chamber and exert a weight on a diaphragm gasket functioning as a common-wall of the two adjacent chambers. The diaphragm gasket exerts pressure resulting from the liquid weight, on the lower chamber containing the pressure sensor designed to measure the pressure exerted on the lower chamber. In some embodiments, the device and method disclosed herein are used for measuring changes in the pressure at the bottom of the container, wherein the pressure changes are indicative of changes in the liquid level. In some embodiments, the measured pressure can be one or more pressure values measured in a continuously fashion by a one or more pressure sensors.

Pressure sensor systems for measuring a liquid pressure and deriving a liquid level from the measured pressure using gas pressure sensing devices. In one embodiment, liquid pressure results in compression or decompression of a trapped gas (as an example, air), wherein the gas pressure is detected by a gas pressure sensing device directly or a gas pressure sensing device that is protected inside a flexible pouch filled with a liquid. In another embodiment, a gas pressure sensing device is packaged in a flexible pouch filled with an inert liquid to protect the sensing device and circuit thereof from external contaminants while accurately transferring pressure from the liquid through a protective barrier. Application of such sensors in a wireless flood or a wireless liquid level measurement system is described as well.

The sensor device serves for detecting the absence or presence of a liquid (1) at the outlet (10a) of a feed line (10) through which there can be fed a feed substance which, when exiting from the outlet, has a pressure (p) in the feed line which has a course over time with a first characteristic in the absence of the liquid and has a course over time with a second characteristic in the presence of the liquid. The sensor device includes a sensing instrument (20-23) for sensing the pressure fluctuations in the feed line (10) and evaluator (30) which is designed to assign the sensed pressure fluctuations to the first or second characteristic and to generate a corresponding signal which indicates whether the liquid (1) is absent or present at the feed line outlet (10a).

The invention relates to a device (1) for determining a filling level of a liquid (F) in a container (B), comprising a submersible unit (2) having a pressure sensor unit (3) and a transmitter unit (14) configured as a radio transmitter unit, an ultrasonic transmitter unit or a light signal transmitter unit, and a float unit (5) having a further pressure sensor unit (6) and a further transmitter unit (15) configured as a radio transmitter unit, wherein the further pressure sensor unit (6) is arranged at or in a floating body (7) of the float unit (5) in such a manner that, if the float unit (5) is arranged in the liquid (F) for which the device (1) is intended to determine the filling level, the further pressure sensor unit (6) is arranged below the surface (O) of the liquid (F).

A triple bubbler system includes a first fluid probe, a second fluid probe, a third fluid probe, a gas source operably coupled to the first fluid probe, the second fluid probe, and the third fluid probe and configured to meter gas through the first fluid probe, the second fluid probe, and the third fluid probe to form bubbles at tips of each of the first fluid probe, the second fluid probe, and the third fluid probe, and a cover member disposed over the tips of the first, second, and third fluid probes and configured to at least partially prevent bubbles formed and escaping the tips of the first, second, and third fluid probes from interfering with other bubbles formed at each other tips. The bubbler system includes a thermocouple having a plurality of junctions disposed along an axis parallel to longitudinal axes of the first, second, and third fluid probes.

A car wash additive measuring system and method use a bubbler which provides a flow of pressurized gas through each bulk container. A pressure of each individual flow of pressurized gas is measured by a pressure transducer to output a signal indicative of the level of additive stored in the container. Flow rates of the respective flow of pressurized gas may be adjusted to accommodate particular additives.

A triple bubbler system includes a first fluid probe, a second fluid probe, a third fluid probe, an gas source operably coupled to the first fluid probe, the second fluid probe, and the third fluid probe and configured to meter gas through the first fluid probe, the second fluid probe, and the third fluid probe to form bubbles at tips of each of the first fluid probe, the second fluid probe, and the third fluid probe, and a cover member disposed over the tips of the first, second, and third fluid probes and configured to at least partially prevent bubbles formed and escaping the tips of the first, second, and third fluid probes from interfering with other bubbles formed at each other tips. The bubbler system includes a thermocouple having a plurality of junctions disposed along an axis parallel to longitudinal axes of the first, second, and third fluid probes.

A method for aspirating a first liquid medium from a sample container with a laboratory automation device, wherein the first liquid medium is above a second liquid medium, which has a higher density and/or viscosity as the first liquid medium comprises: detecting a surface position of a surface of the first liquid medium; calculating an estimated interface position of an interface between the first liquid medium and the second liquid medium from the surface position and calculating a safety position between the surface position and the estimated interface position by adding a safety offset to the estimated interface position; and lowering a pipette of the laboratory automation device into the sample container and aspirating the first liquid medium from the sample container with the pipette by generating an underpressure in the pipette until a pipette tip of the pipette reaches the safety position.

An assembly includes at least one container, an injection medium supply, at least one flow line extending from the injection medium supply to an interior portion of the at least one container; and a pressure transducer coupled to each of the at least one flow line.

Pressure sensor systems for measuring a liquid pressure and deriving a liquid level from the measured pressure using gas pressure sensing devices. In one embodiment, liquid pressure results in compression or decompression of a trapped gas (as an example, air), wherein the gas pressure is detected by a gas pressure sensing device directly or a gas pressure sensing device that is protected inside a flexible pouch filled with a liquid. In another embodiment, a gas pressure sensing device is packaged in a flexible pouch filled with an inert liquid to protect the sensing device and circuit thereof from external contaminants while accurately transferring pressure from the liquid through a protective barrier. Application of such sensors in a wireless flood or a wireless liquid level measurement system is described as well.