Patent GB-241684-A (GB)
Title: Improvements in or relating to electrical apparatus for the measurement of the leveland flow of liquids
IPC: G01F23/24
Filed: 1924-09-23
Abstract: 241,684. Shotter, G. F. Sept. 23, 1924. Indicators, electric.-Relates to apparatus for indicating or recording the level or flow of liquids of the type described in Specification 17044/11, [Class 40 (i), Electric signalling systems &c.], wherein the height of the liquid between electrodes determines the resistance in an indicating circuit and compensating electrodes are provided for neutralizing the effect of polarization &c. The invention resides in improvements in the main and compensating electrodes. Figs. 1 and 2 show the, arrangement of the main electrodes. A tubular member 1 of triangular cross-section is formed of insulating material such as glazed earthenware and carries at each end cathodes 32 formed of metal gauze supported in frames 33. Each frame is mounted at the bottom on a block 35 supported on a bracket 37 and at the top on a bar 34 which is secured by pivoted locking members 36 on a frame 11. A frame 11 is provided at each end for supporting the tubular member. and the frames are attached to rods 15 which support the apparatus in the liquid. Midway of its length, the tube 1 has an anode 25 of metal gauze which is inserted into the tube through a slot in the top. Between the anode and the cathodes, a number of shields 3 of insulating material are arranged in order that the relationship between the height of liquid within the tube 1 and the flow of liquid over a notch may follow a straight line law. The shields are adapted to Interlock by means of pins 4. The shape of the shields is dependent upon the shapes of the notch and tubular member. The electrodes have apertures corresponding in position and shape to the shields. Fig. 4 shows one form of compensating apparatus. A metal gauze electrode, which comprises two or three separate parts 54, is supported at the edges of circular members 41, 42 of insulating material, such as glazed earthenware. Each part 54 is connected electrically by a ring 59 which is connected to a terminal 63. The other electrode comprises metal gauze 64 supported in a grooved bobbin 65 which is carried by a rod 68 and is inserted, through the tubular extension 44 of the member 42. This electrode is positioned correctly by a V-shaped projection 67. The members 41, 42 are supported from a ring 48 by rods 49, 52 which may be adjusted to vary the distance between the members. Fig. 6 shows a modified form of compensating apparatus. A cylindrical member 76 of glazed earthenware has a wire gauze anode 78 and wire gauze cathodes 79 which are inserted through tubular extensions 77, 80, 81. The electrodes may be formed of platinized copper, nickel or ferro-nickel gauze or platinum or platinized wire wound on frames. In use the main electrodes are included in a circuit, which provides the deflecting force of the indicator and the compensating electrodes are connected in the controlling circuit. Guard wiring may be applied to the apparatus for preventing the measurement of leakage currents. The Provisional Specification states that the tubular member is supported by a bearer having a V-shaped groove extending along the bottom of the member; the circular members 41, 42, Fig. 4, are supported by clamps comprising rings; the cathodes of the apparatus shown in Fig. 6 may be adjustably mounted and that of the tubular member of the main electrode systems is in two or more parts which are jointed, a leakage path of known dimensions is provided and the leakage current is compensated in the indicator. Specification 163,739, [Class 106 (iv), Indicating &c.], also is referred to.