4-electrode conductivity sensor with zero external field
OwnerNeil L. Browninventor
Life of this patent
Estimating the term…
Abstract
A conductivity sensor configuration which has essentially no external electrical field so that the calibration of the sensor is not affected by the existence of nearby external objects or fouling on the exterior parts of the sensor. Additionally, the sensor is relatively insensitive to electrode fouling or electrode polarization. The sensor includes a tube through which the liquid to be measured flows. An inner electrode plate extends partially along the length of the tube dividing the central portion of the tube into two sections. Two inner electrodes are located on the inner wall, one on each side, and two outer electrodes are located on the inside of the tube opposite the inner electrodes.
Claims19
A conductivity sensor, comprising:
- a hollow tube made of an insulating material and being of uniform cross-section along at least a portion of its length and open at each end;
- a divider plate, made of an insulating material, shorter in length than the tube and located midway along the length of the tube, and which extends completely across the tube so as to divide the tube longitudinally into two equal halves on either side of the plate;
- two inner electrodes respectively located on either side of the divider plate and logitudinally positioned in the center of each side of the plate;
- two outer electrodes, each located inside the tube in one of said halves on the inside wall opposite an inner electrode;
- and
- terminal means for providing an electrical connection to each of the inner and outer electrodes.
A conductivity sensor, comprising:
- a hollow rectangular tube of uniform cross-section along its length, having top, bottom, and side walls, and being open on each end;
- a flat electrode plate shorter than the length of the tube, extending from the top wall to the bottom wall of the tube parallel to the side walls, and being located midway between the side walls and midway along the length of the tube;
- two outer electrodes, each comprising vertical stripe formed on the inside of a respective one of the side walls of the tube midway along its length;
- two inner electrodes, each comprising a vertical stripe formed on a respective one of the sides of the electrode plate midway along its length;
- and
- means for providing electrical connection to each of the electrodes.
A conductivity sensor, comprising:
- a hollow tube made of an insulating material, open at each end, and having its length as its largest dimension;
- a divider plate, made of an insulating material, shorter in length than the tube and located inside the tube and partway along the length of the tube so that the tube extends beyond the ends of the divider plate, the divider plate extending completely across the tube so as to divide the tube into two sections on either side of the plate;
- two inner electrodes respectively located on either side of the divider plate;
- two outer electrodes, each located on the inner wall of the tube, each electrode being positioned opposite and across from an inner electrode;
- and
- terminal means for providing an electrical connection to each of the inner and outer electrodes.
Dependencies are inferred from the claim text.