pitch circle

noun Machinery.

an imaginary circle within the profiles of the teeth of a gear, such that it rotates against a similar circle rotating at the same rate on a meshing gear.

Origin of pitch circle

First recorded in 1810–20

Also called pitch line.

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for pitch circle

Historical Examples of pitch circle

Let BB be part of the pitch-circle, and a the point where a tooth is to cross it.
Encyclopaedia Britannica, 11th Edition, Volume 17, Slice 8
Various
The distance, measured along the pitch-circle, from the face of one tooth to the face of the next, is called the pitch.
Encyclopaedia Britannica, 11th Edition, Volume 17, Slice 8
Various

British Dictionary definitions for pitch circle

pitch circle

noun

an imaginary circle passing through the teeth of a gearwheel, concentric with the gearwheel, and having a radius that would enable it to be in contact with a similar circle around a mating gearwheel

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012