| 摘要 |
PURPOSE:To eliminate errors due to deflecting flows and to make the size compact, by using magnetic field generating devices which generate magnetic flux whose first order differential or quadratic differential becomes zero, and making the size of the hole in a casing smaller than the size of magnetic pole plates. CONSTITUTION:The magnetic field generating devices are mounted on the top part and the bottom part of a drum shaped main body casing 1 made of a ferromagnetic body. A measuring pipe 3 made of a nonmagnetic body is concentrically arranged in the main body casing and held and fixed by end plate parts 1d at both ends. A pair of electrodes 5 are mounted on the measuring pipe 3 in the direction of the axial line of the magnetic field generating devices 2 and in the direction of the pipe axis of the measuring pipe 3, at the positions of the axial lines of diameters which are crossed at a right angle each other. An exciting coil 4, which is inserted in the hole in each protruded part 1a of the main body casing 1, is excited by a square wave, a triangular wave, or DC. The magnetic flux, whose first order differential or quadratic differential is zero, is generated and applied to fluid. The relationship lP/lH is specified, where lH is the size of the hole in each protruded part 1a and lP is the size of each magnetic pole plate 2a in the direction perpendicular to the pipe axis of the measuring plate. |
