JIS B 0121:1999

This Standard specifies symbols for geometrical data for use in gear notation. It consists essentially of two parts: - on the one hand, the principal symbols, composed either of a single basic letter, or of a basic letter and suffix or sign which are generally inseparable for the given term; - 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. The Annex A 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 Standard and a combination of which may possibly be used for the notation of any other term of geometrical data not explicitly mentioned in the Standard.