| 摘要 |
1525742 Measuring conductivity of fluids SED SYSTEMS Ltd 13 Aug 1975 [18 Oct 1974] 33665/75 Heading GIN A sensor for use to determine the conductivity of a fluid, e.g. milk to determine the onset of mastitis in a cow, comprises a tube 1 of electrically insulating material through which the fluid is passed in use; cylindrical electrodes 2, 3, 4 spaced axially of and about the tube, that 2 forming the first electrode of, and the pair 3, 4 forming the second electrode of, a capacitor of which the tube and milk therein is the dielectric, whereby an alternating current flow is electrostatically induced in the milk. A conductive shield cylinder 5 may be provided. An r.f. source 8 Fig. 2 energizes each conductor 7 in a time division sequence and the A.C. drawn in a respective conductor sensed by toroids, 11-14, indicates the milk conductivity in the corresponding tube. In an alternative embodiment, Fig. 4 (not shown) four tubes (16, 17, 18, 19) are provided for the four quarters of the cow, each tube having respective first (20-23) and second (24-5) electrodes. Conductors (26-29) connected to a respective first electrode are together passed through a toroid (30) the terminals of which are connected to a current detecting means. |
