Eccentricity
The variation of the outer diameter of a shaft surface when referenced to the true geometric centreline of the shaft. Often described as Out-of-roundness.
Conic
The ratio of the length of the radius vector through a point on the conic to the distance of the point from the directrix.
Ellipse
The eccentricity e of an ellipse can be computed by the formula:
where: a is the semimajor axis and b is the semiminor axis.
Ellipse Linear Eccentricity
The ratio of the distance between the center and focus of an ellipse to its semimajor axis.
See also: Eccentricity Ratio, Ellipse, Off Centre, Runout.
Subjects: Mechanical Engineering