The use of simple teeth surfaces in non-conjugate gears

Nowadays, the dominant place in the practical use of rotational motion transmission mechanisms has conjugate, and, in particular, teeth gear. Reproduction of high-order surfaces used in conjugated gears requires the use of sophisticated and expensive equipment. An alternative to such gears are approximate gears. The paper analyzes the possibility of using gears with non-conjugate engagement when using the simplest surfaces - a plane, a cylinder and their various combinations, as the working surfaces of the teeth. It is shown that with the simplest outlines of the teeth it is possible to get the high-quality transmission. The results of mathematical modeling of approximate gears are presented. A comparison of the studied gears with the involute one in terms of the cyclic error of the tooth frequency is given. The resulting values of the position error and the gear ratio are minimal and, in particular, for multi-row gears can be negligible. The insensitivity of approximate gears to the errors in wheel manufacturing and gear assembly is shown. Several gear configurations and various motion transmission configurations are provided. Prospects for the use of gears with the simplest outlines of the teeth are associated with the lack of need for complex gear-processing equipment and the possibility of manufacturing and repair in the field conditions. In addition, such transmissions are indispensable for experimental installations because of the possibility of rapid changes in parameters that do not require significant time for design and manufacture.

gears, non-conjugate gears, approximate gearing, multi-row gear, drive gear, position error, simple tooth shapes