Transmission error is an important physical quantity used to describe the deviation degree between the actual angle and the theoretical angle of the driven gear when the helical gear pair is engaged. Its fluctuation degree reflects the transmission stability of the helical gear pair, and has an impact on the helical gear vibration noise that cannot be ignored. However, the higher the Hertz contact stress on the tooth surface, the easier the helical gear is to fatigue failure (mainly pitting) under the same material.
Many researches believe that gear transmission error and Hertz contact stress are important indicators to evaluate the vibration and noise characteristics of helical gear pairs and the strength (service life) of helical gears. Considering that there are many indicators to measure the meshing performance of helical gears, this paper only explores the influence of helical gear parameters on its transmission error, Hertz contact stress and transmission efficiency.
According to the suggestions on the selection of pressure angle and helix angle for new energy vehicles, and in combination with the actual parameters of the helical gear pair studied in this topic, the selection range of pressure angle and helix angle is set as 15 °~22.5 ° and 30 °~33 ° respectively, and the tooth width of small gear and big gear is set as 22mm~40mm and 20mm~50mm respectively.