Expressed as θ, the involute polar angle is the angle between a radius vector to a point, "P", on an involute curve and a radial line to the intersection, "A", of the curve with the base circle.1
Notes
1. "ANSI/AGMA 1012-G05", "Gear Nomenclature, Definition of Terms with Symbols".
Wikimedia Foundation. 2010.
Involute — In the differential geometry of curves, an involute of a smooth curve is another curve, obtained by attaching an imaginary taut string to the given curve and tracing its free end as it is wound onto that given curve; or in reverse, unwound. It is … Wikipedia
List of gear nomenclature — Gears have a wide range of unique terminology known as gear nomenclature. Many of the terms defined cite the same reference work.[1] Contents 1 Addendum 2 Addendum angle 3 Addendum circle … Wikipedia
Dual curve — Curves, dual to each other; see below for properties. In projective geometry, a dual curve of a given plane curve C is a curve in the dual projective plane consisting of the set of lines tangent to C. There is a map from a curve to its dual,… … Wikipedia
Logarithmic spiral — A logarithmic spiral, equiangular spiral or growth spiral is a special kind of spiral curve which often appears in nature. The logarithmic spiral was first described by Descartes and later extensively investigated by Jakob Bernoulli, who called… … Wikipedia
