pitch circle

American  

noun

Machinery.

1. 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.

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pitch circle British  

noun

1. 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

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Etymology

Origin of pitch circle

First recorded in 1810–20

Example Sentences

See Examples For:

pitch circle

On the pitch circle p p, divisions 1, 2, 3, 4, &c., for the thickness of teeth and the width of the spaces are marked.

From Modern Machine-Shop Practice, Volumes I and II by Rose, Joshua

Thus, to strike the other curve of the tooth, mark off from a the thickness of the tooth on the pitch circle p p, producing the point h.

From Modern Machine-Shop Practice, Volumes I and II by Rose, Joshua

From a mark on the pitch circle, as at b, a radius equal to the pitch of the teeth, and the thickness of the tooth as a k.

From Modern Machine-Shop Practice, Volumes I and II by Rose, Joshua

The flank of each wheel is struck with a tracing point, thus attached to the pitch circle of the other wheel.

From Modern Machine-Shop Practice, Volumes I and II by Rose, Joshua

Then for the flanks place the slant edge of the odontograph coincident and parallel with e, and let its corners coincide with the pitch circle as shown.

From Modern Machine-Shop Practice, Volumes I and II by Rose, Joshua