Sensor system for fluids

Patent metadata

Field	Value
Publication number	US-11898978-B2
Application number	US-202217951852-A
Country	US
Kind code	B2
Filing date	Sep 23, 2022
Priority date	Nov 8, 2021
Publication date	Feb 13, 2024
Grant date	Feb 13, 2024

Abstract

A sensor system, particularly for monitoring the mixing of at least two fluids and a method for monitoring the mixture of at least two liquids. The present invention provides a sensor system for fluids, comprising at least two level sensor which are arranged vertically one upon the other on and connected to an electronic circuit board, four electrodes of four conductivity sensors which are arranged horizontally next to each other at the bottom of and connected to the electronic circuit board; and a temperature sensor which is connected to the electronic circuit board; a connector for connecting the electronic circuit board to a controller; wherein the electronic circuit board is embedded in a hot melt compound which is surrounded by an injection molded housing.

First claim

What is claimed is:

1. A sensor system for fluids, comprising:
two level sensors which are arranged vertically one upon the other on and connected to an electronic circuit board;
four electrodes of four conductivity sensors which are arranged horizontally next to each other at the bottom of and connected to the electronic circuit board, wherein the four conductivity sensors are arranged below the lower level sensor;
a temperature sensor which is connected to the electronic circuit board; and
a connector for connecting the electronic circuit board to a controller;
wherein the electronic circuit board is embedded in a hot melt compound which is surrounded by an injection molded housing.

2. The system of claim 1 , wherein all sensors in the sensor system are made of a conductive plastic.

3. The system of claim 1 , wherein the two outer electrodes of the conductivity sensors apply a defined current and the two inner electrodes conductivity sensors measure the current for determining the conductivity of the fluid.

4. The system of claim 1 , wherein the at least two level sensors are optical sensors.

5. The system of claim 4 , wherein each tip of the at least two level sensors is made of a transparent material.

6. The system of claim 5 , wherein the tip of a level sensor is a prism.

7. The system of claim 1 , wherein the temperature sensor is located below the conductivity sensors.

8. The system of claim 1 , wherein the temperature sensor is thermally insulated from the injection molded housing.

9. A method for monitoring the mixture of fluids, comprising the steps of:
mixing at least two fluids in a container;
measuring conductivity, fluid level and temperature of the mixture with a sensor system for fluids, wherein the sensor system comprises:
at least two level sensors arranged vertically one upon the other and connected to an electronic circuit board;
four electrodes of the at least two level sensors arranged horizontally next to each other at the bottom of and connected to the electronic circuit board;
a temperature sensor connected to the electronic circuit board;
a connector for connecting the electronic circuit board to a controller,

wherein the electronic circuit board is embedded in a hot melt compound which is surrounded by an injection molded housing; and
determining whether the conductivity is in a pre-defined range.

10. The method of claim 9 , wherein a ratio of the at least two fluids is adjusted according to the determined conductivity if the measured conductivity is outside the pre-defined range.

Assignees

• Stratec Se

Inventors

• Burkart Michael
• Maier Ralf

Classifications

• G01N27/07 Primary

  Construction of measuring vessels; Electrodes therefor · CPC title

• G01N27/046

  provided with temperature compensation · CPC title

• G05D11/135 Primary

  by sensing at least one property of the mixture (G05D11/139 takes precedence) · CPC title

• B01F35/2133

  Electrical conductivity or dielectric constant of the mixture · CPC title

• B01F35/2112

  Level of material in a container or the position or shape of the upper surface of the material · CPC title