The lengths of the links comply with the conditions: A͞C:A͞B=C͞P:B͞Q, A͞E:A͞D=E͞P:D͞Q and θ=α+β. Links 1 and 2 turn about fixed axis A which is the centre of inversion transformation. Links 3 and 5 are connected by turning pairs B and C to link 2 and by turning pairs Q and P to links 4 and 6. Links 4 and 6 are connected by turning pairs D and E to link 1. When point P or Q travels along any arbitrary curve, the other point describes a curve which is the inversion of the first curve. Hence, the mechanism accomplishes inversion transformations of the form A͞P×A͞Q=B͞Q×C͞P=A͞B×A͞C=D͞Q×E͞P-A͞D×A͞E=const.
$732$LW,GI$