Flow meter

Abstract

Abstract 847,861. Flow-meters. BRITISH OXYGEN RESEARCH & DEVELOPMENT Ltd. Feb. 5, 1959 [Feb. 7, 1958], No. 4066/58. Class 40 (1). [Also in Groups XXVI and XXXIV] In a flow-meter of the type wherein a liquid flows through a working chamber and so causes cyclic movements of a flow-responsive member, the latter is made of polytetrafluoroethylene (or of a metal impregnated therewith) and is not connected mechanically with the recording equipment; the flowmeter is thus suitable for liquds having boiling-points substantially below atmospheric temperatures, e.g. liquid oxygen. In Fig. 1 the liquid enters at 11 and passes through an aperture 16 into the working chamber 13 where it acts on the radial diaphragm of a rotary piston 18 and causes the central pin 19 of the latter to travel in a circle around studs 23, 25 attached respectively to the bottom and top of the chamber. The piston itself is made of polytetrafluoroethylene, or of aluminium, brass or bronze impregnated therewith, and the central pin, which is of magnetized steel, is prevented from rubbing directly on the studs by providing the latter with an exterior lining 27 of polytetrafluoroethylene. An iron pin 29 projects through the top of the casing and forms the core of an inductance coil 30 so that a voltage pulse is induced in the coil once per revolution of the piston. This pulse is amplified, squared and fed to a unit (not shown) which measures the amount or rate of flow. In a modification (Figs. 2 and 3, not shown), the pick-up is by means of a mild steel pin sunk in the peripheral wall of the piston co-operating with a permanent magnet via a pin around which the coil is wound. The pulses can be generated photo-electrically or capacitatively instead of inductively.

Inventors

• 👤 Alfred Thomas Brand

Bibliographic Details