GB/T 11366-2025Basic terminology of planetary drives (English PDF)

Foreword

This document complies with the provisions of GB/T 1.1-2020 "Standardization Work Guidelines Part

1.Structure and Drafting Rules of Standardization Documents". Drafting. This document replaces GB/T 11366-1989 "Basic Terminology of Planetary Transmissions". Compared with GB/T 11366-1989, except for structural adjustments and... Aside from editorial changes, the main technical changes are as follows:

a) Change the term "planetary gear transmission mechanism" to "planetary gear drive" (see 3.1, 1989 edition 3.1);

b) The definitions of "planetary gear" and "planet carrier" have been changed, and the permitted terms "planetary gear", "carrier", and "swing arm" have been added (see

3.2 and 3.6). (Sections

3.4 of the 1989 edition)

c) Added the terms and definitions for "output component" and "output shaft" (see

d) The following terms have been removed. "2K-H type planetary gear transmission mechanism", "3K type planetary gear transmission mechanism", and "KVH type planetary gear transmission machine". The terminology and definition of "structure" (see 3.5-

3.7 of the 1989 edition);

e) Added relevant terms and definitions for "classification" (see Chapter 4);

f) Added "NGW type", "NW type", "NN type", "ZUWGW type", "N type", "NGWN type", "WW type", and "2K-H type" The terms and definitions of "3K type," "KHV type," "2K-V type," and "KH type" are provided in sections 4.1.1-

4.1.7 and 4.2.1-4.2.5.

g) The following terms have been deleted. "involute internal gear pair with few tooth difference", "circular arc gear pair with few tooth difference", "circular arc spur gear", and "ordinary epicycloid circular arc spur gear". The terms and definitions for "variable amplitude epicycloid spur gear" and "variable amplitude involute spur gear" (see sections

4.13 of the 1989 edition) are as follows: 4.13.1~4.13.3);

1 Scope

GB/T 11366-2025 is the Chinese national standard on basic terminology of planetary drives, in the field of mechanical systems and components. The /T suffix marks it as a recommended standard: it is not compulsory by itself, but it becomes binding as soon as a contract, a tender or a customer specification calls it up - which in practice is how most foreign buyers meet it. It was issued on 31 October 2025 by the State Administration for Market Regulation; Standardization Administration of China, and has been in force since 1 May 2026. Classification: ICS 21.200, CCS J17. This page is published from the official record of the standard held by the Chinese standards administration: the identification, the dates, the classification and the issuing body are taken from there. The clause text, the tables and the numeric limits are in the document itself, which is delivered complete in English translation.

This document defines the basic terminology and definitions related to the general concepts, classifications, and applications of planetary transmissions. This document applies to the definition of various planetary transmission types, including low tooth difference, harmonic, Ravina, and Simpson types. Planetary roller screw, planetary cycloid.

2 Normative references

This document has no normative references.

3 General Concepts

3.1 Planetary gear drive A transmission system consisting of a central gear, planetary gears, a planetary carrier, and an output component.

Note. The center gear (including the sun gear and internal gear ring), planetary gears, planet carrier, and output components are collectively referred to as the basic components of a planetary gear transmission. See Figure 1. Index number explanation. 1

---Internal gear ring; 2

---Planetary gears; 3

---Input axis; 5

---Planet Carrier; 6

---Output components. Figure