Patent GB-376253-A (GB)
Title: Improvements in viscosimeters
IPC: G01N11/08
Filed: 1931-03-23
Abstract: 376,253. Testing and measuring viscosity of liquid. ALBERSHEIM, W. J., 175, Riverside Drive, and KONHEIM, H. S., 454, Fort Washington Avenue, both in New York, U.S.A. March 23, 1931, No. 8927. Convention date, March 22, 1930. [Class 106 (ii).] Comprises apparatus wherein the liquid to be tested passes successively through two orifices the resistance to flow through one orifice being primarily dependent upon the kinetic effect for thin liquids but upon a combined friction and kinetic effect for thicker liquids, the resistance through the other orifice being dependent substantially on friction only for both thin and thick liquids. The casing is formed in two halves 11, 12 bolted together. The top half 11 is provided with a valve casing 20 screwed in order to enable adjustment of the seating 21 relative to the valve 30. A T-piece 22 connects with an inlet pipe 26 and is provided with a screw cap 23 and a screen 27. Inside the casing is mounted a bellows 31 joined in an airtight manner to the upper casing. The bottom plate 33 of the bellows is provided with a screwed stud 34 to receive the valve stem 36, a lock nut 37 being provided. Adjustment of the valve opening may be made by screwing the valve stem in and out of the nut 34 or by moving the valve housing 20. In addition a further adjustment may be effected by making the valve stem in two parts screwed together shim pieces 38 being inserted between the parts. Screw plugs 40, 41 are provided inside and outside of the bellows so that gauges may be fitted at these places if desired. The plate 33 is provided with an orifice 50. A spring 60 may be adjusted by a screw 62 to reinforce the elasticity of the bellows. A jet 70 of the interior curved shape shown is fitted to the lower part of the casing, and a gauge 71 communicates with the space outside the bellows. The liquid to be tested enters through the pipe 26 and extends the bellows downwards, controlling by means of the valve 30 the flow. It flows out from the bellows through the orifice 50 and creates a pressure outside of the bellows tending to counteract the pressure inside. By suitable proportioning of parts, a constant speed of flow is maintained through the orifice 50. The pressure reactions due to the jet 70 on liquid supplied at constant speed is proportional to the viscosity and may be measured by the gauge 71. In order to make use of pressure gauges which are sufficiently sensitive at the lower pressure ranges effective also for the higher range it is necessary to make the orifice 50 of a certain length. The gauge is fitted with " low " and " high " limit contacts 74, 75 which are wired up to a lamp 77 and battery 78 in such a manner that the lamp lights and remains lighted if the pointer 73 engages either contact 74, 75. A contact 92 in this circuit engages the plate 33 and breaks contact when the needle returns to zero on the apparatus being placed out of use. In a modification, the bellows is replaced by a diaphragm provided with a projection engaging a ball valve, the valve stem 36 being dispensed with. In a further modification, the bellows and top plate are retained and a pipe connected to the top plate communicates with the interior of the bellows, the pipe being provided with an orifice corresponding to the orifice 50 and with an orifice 70, the gauge being connected to the space between the orifices.