Patent ID: 8381586
Filing Date: 2013-02-26
Classification: G01F

Abstract:
1. A water meter comprising: a rotating magnet having an axis of rotation; a measuring chamber comprising a ball socket with an opening coaxial with said magnet; a ball and disc disposed within said measuring chamber, said ball disposed within said ball socket and comprising a diametric bore with at least one open end; a unitary biaxial member comprising a drive shaft joined to a spindle having a longitudinal axis offset angularly from that of the drive shaft; wherein said spindle is disposed within said bore in said ball and free to rotate therein and said drive shaft extends from said ball through the opening in said ball socket to couple with said magnet, said opening constraining the drive shaft into coaxial alignment with said rotating magnet, such that the angular offset between the axis of the drive shaft and the axis of the spindle causes said spindle to trace a cone and said ball and disc to nutate in response to water flow through said measuring chamber, thereby translating said water flow into rotation of said drive shaft and magnet, and wherein said spindle is joined to said drive shaft by a cap, said cap being disposed within a cavity in said ball defined substantially by a small circle of said ball and is adapted to rotate therein.