Patent ID: 6557430
Filing Date: 2003-05-06
Classification: G01N,G01P

Abstract:
A pole piece assembly for producing a region of space having a substantially constant magnetic force field, the assembly comprising:(a) a first pole piece having a substantially curved flux concentrating portion, the substantially curved flux portion comprising: (i) a first distal end having a curved portion, wherein the curved portion of the first distal end of the first pole piece comprises a radius; and (ii) a second distal end having a curved portion, wherein the curved portion of the second distal end of the first pole piece comprises an approximately hyperbolic function, and wherein the hyperbolic function comprises y(x)=9.544/x2âˆ’12.719, wherein x and y are Cartesian coordinates with the origin placed at the intersection of the plane of symmetry separating the pole pieces and a plane tangent to the radial portion of the distal ends of the pole pieces; (b) a second pole piece having a substantially curved flux concentrating portion, the substantially curved flux portion comprising: (i) a first distal end having a curved portion, wherein the curved portion of the first distal end of the second pole piece comprises a radius; and (ii) a second distal end having a curved portion, wherein the curved portion of the second distal end of the second pole piece comprises an approximately hyperbolic function, and wherein the hyperbolic function comprises y(x)=9.544/x2âˆ’12.719, wherein x and y are Cartesian coordinates with the origin placed at the intersection of the plane of symmetry separating the pole pieces and a plane tangent to the radial portion of the distal ends of the pole pieces; (c) wherein the first and second pole pieces are configured to form an inter-polar air gap wherein (i) the first distal end of the first pole piece is approximately opposite the first distal end of the second pole piece; and (ii) the second distal end of the second pole piece is approximately opposite the second distal end of the second pole piece; and (d) a device for producing a magnetic flux in flux communication with the first and second pole pieces.