BS ISO 19347:2015 pdf download.Synchronous belt drives — Imperial pitch trapezoidal profile system — Belts and pulleys
1 Scope
This International Standard specifies the principal characteristics of synchronous endless belts and pulleys for use in synchronous endless belt drives 1) for mechanical power transmission and where positive indexing or synchronization is required.
The principal characteristics includes the following:
a) belt nominal tooth dimensions;
b) belt length and width dimensions and tolerances;
c) belt length-measurement specifications;
d) pulley grooves dimensions and tolerances;
e) pulley dimensions and tolerances;
f) pulley quality specification.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 254, Belt drives —Pulleys — Quality, finish and balance
ISO 1101, Geometrical product specification (GPS) — Geometrical tolerancing — Tolerances of form,orientation, location and run-out
3 Profiles
Seven profiles for synchronous drives are standardized: MXL, XXL, XL, L, H, XH, XXH.
The profiles and the corresponding belt pitches are given in Table 1.
4 Belt dimensions and tolerances
4.1 Belt tooth dimensions
The nominal belt tooth dimensions are the same for one-sided and double-sided belts; they are given in Table 2 and are shown in Figures 1, 2, and 3.
Two types of double-sided synchronous belts are standardized. Type A (see Figure 2) has symmetrical teeth and Type B (see Figure 3) has staggered teeth.