Draft International Standard
ISO/DIS 21771-1.2
Cylindrical involute gears and gear pairs — Part 1: Concepts and geometry
Reference number
ISO/DIS 21771-1.2
Edition 1
International Standard
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ISO/DIS 21771-1.2
This Draft International Standard is in the enquiry phase with ISO members.
Will replace ISO 21771:2007

ISO/DIS 21771-1.2

ISO/DIS 21771-1.2
CHF 129
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This document specifies the geometric concepts and parameters for cylindrical gears with involute helicoid tooth flanks. Flank modifications are included. The formulas in this document apply to all pressure angles. It also covers the concepts and parameters for involute cylindrical gear pairs with parallel or crossed axes, and a constant gear ratio. Gear and mating gear in these gear pairs have the same basic rack tooth profile.

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