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BS 2519-2:1976



The latest, up-to-date edition.

Glossary for gears Notation

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Cooperating organizations
0 Introduction
1 Scope and field of application
2 Principal symbols and additional suffixes or signs
Recapitulative index of letters and signs used in this
International Standard
1 Principal symbols
2 Additional suffixes or signs
3 Basic italic letters
4 Suffixes and signs

Symbols for geometrical data for use in gear notation.

This International Standard specifies symbols for geometrical data for use in gear notation. It consists essentially of two parts:

  • on the one hand, the principal symbol, composed either of a single basic letter, or of a basic letter and suffix or sign which are generally inseparable for the given term (see Table 1);
  • on the other hand, additional suffixes or signs which may be added if necessary to the principal symbols, in order to imply a particular qualification of the given term (see Table 2).

The Annex gives lists classified in alphabetical order according to the Roman and Greek alphabets, on the one hand of the basic letter symbols, and on the other hand of the suffixes and signs which have been used in the establishment of this International Standard and a combination of which may possibly be used for the notation of any other term of geometrical data not explicitly mentioned in this International Standard.

Also numbered as ISO 701 (06/2005) Reviewed and confirmed by BSI, September 2005. (08/2005)
British Standards Institution

BS 3696-1:1977 Specification for master gears Spur and helical gears (metric module)
BS 978-5:1965 Specification for fine pitch gears Hobs and cutters
BS 4582-2:1978 Specification for fine pitch gears (metric module) Hobs and cutters
BS 3550:1963 Specification for involute splines
BS 5221:1987 Specification for general purpose, metric module gear hobs
BS 436-1:1967 Spur and helical gears Basic rack form, pitches and accuracy (diametral pitch series)
BS AU 252:1993 Specification for diametral pitch starter motor pinions for road vehicles
BS 436-3:1986 Spur and helical gears Method for calculation of contact and root bending stress limitations for metallic involute gears
BS 545:1982 Specification for bevel gears (machine cut)
BS 235:1987 Specification for gears for electric traction
BS 2518-2:1977 Specification for rotary form relieved gear cutters Metric module
BS 1807:1981 Specification for marine main propulsion gears and similar drives: metric module
BS 721-2:1983 Specification for worm gearing Metric units
BS 436-2:1970 Spur and helical gears Basic rack form, modules and accuracy (1 to 50 metric module)

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