GB984941A - Rotary fluid-flow measuring devices - Google Patents

Abstract

984,941. Rotary meters. GLACIER METAL CO. Ltd. Feb. 14, 1964 [Feb. 16, 1963], No. 6376/63. Heading F1F. A rotary fluid flow meter of the kind having a rotor rotatable by the fluid being measured and mechanism that counts and if necessary integrates the number of revolutions, comprises a rotor 4, Fig. 1, having a weight equal to the weight of the volume of fluid it displaces such that its effective weight is reduced to zero with consequently no load transmitted to the bearing pins 5. Further, the rotor comprises two spaced rows of helical blades 6 with the space between the rows communicating through radial passages 10 with diametrically opposite passages 9a connected to a common inlet (or outlet) 7a and the spaces outside and adjacent the rows communicating through spaced radial passages 11, Fig. 3, with another pair of diametrically opposite passages 9b connected to a common outlet (or inlet) 7b so that in whichever direction flow takes place, the flow is divided into two equal and opposite flows through the meter to cancel out any fluid thrusts acting on the rotor. The rotor is made of light-weight material, e.g., transparent acrylic resin having a specific gravity of 1À2, suitably hollowed out such that its centre of gravity and centre of buoyancy are coincident on the rotor axis and on a central dividing plane of the rotor with its weight equal to the weight of the volume of fluid, e.g., petrol, displaced. With lighter or heavier fluids the rotor cavity may be adjusted accordingly. The body of the meter is also made of translucent material, e.g., acrylic resin and the rotor fitted with an opaque mask 14 so that a source of light 12, Fig. 5 projects a beam of light through the body and roter, interrupted twice per revolution by the mask 14, on to a photoelectric cell 13, to measure rate of flow or mass flow of the fluid in known manner.