Estimation of Transmission Error of Cylindrical Involute Gears by Tooth Contact Pattern.

The correlation between the transmission error of gears and some factors which are usually considered to express characteristics of a tooth contact pattern, such as areal percentage and total length of simultaneous contact lines, is examined, but very poor correlation is found. A new method of estimating the transmission error from a tooth contact pattern is introduced. This is a method of supposing a triangular shape for the composite error on the actual contact line, which results in the ridge figure of the composite error surface as a function of the tooth contact pattern. The transmission error is derived as a function of this ridge figure. The results estimated by this method showed fairly good correlation with the actual transmission error, especially for a low transmitting load. Based on this method, an index value to estimate the amplitude of transmission error of a gear pair by the observation of tooth contact pattern is also introduced.