GB426876A - Improvements in or relating to viscometers - Google Patents

Abstract

426,876. Viscosimeters. RHODIN, J. G. A., 16, Emerson Road, Ilford, Essex, and WESTMAN, Ltd., E. B., 39, Lombard Street, London. Oct. 11, 1933, No. 28093. [Class 106 (ii)] The fluid is caused to flow through a narrow channel one wall of which is movable in the direction of flow and being guided by a parallel motion mechanism through which a gravitational control is applied to measure the force exerted on the movable wall by the fluid flow. A vessel 1 closed by a cover 4 is surrounded by a water vessel 2 for maintaining the contents of the vessel 1 at a uniform temperature. Compressed air is supplied through a channel 3 in the cover and acts on the liquid in the vessel 5 suspended on flanges 6 to force the liquid through an orifice 10 in a diaphragm 9 closing the lower end of a depending tube 8. The liquid passes through the narrow annular channel between the inner walls of the tube 8 and a rod 11 which is suspended from a flexible cord 31 passing over a pulley 15 to a balance weight 16. The rod is also guided to move in a straight line by a parallel motion device. This comprises a weighted lever 25 pivoted on a knife edge B and a second weighted lever 26 pivoted at H the inner ends of the levers being connected by a pivoted link 27 which is connected to a pivoted parallel linkage C, D, E, F, of which the link 29 is pivoted at its mid point 0 to the rod 11. The parts are proportioned so that the point o is guided in a straight line. A needle 21 on the spindle of the pulley 15 indicates the viscosity. A dead weight ball safety valve 19 ensures the pressure of air being at constant value.