Investigation on the high-cycle tooth bending fatigue and thermo-mechanical behavior of polymer gears with a progressive curved path of contact

A systematic combination of experimental and numerical methods was employed in a comprehensive study on the high-cycle tooth bending fatigue of polymer gears with a progressive curved path of contact (S-gears). A polymer/polymer combination was tested where the drive gear was made of POM and the driven one from PA 66. Gears were tested at three different torque levels, i.e. 0.6 Nm, 0.8 Nm, and 1.0 Nm, with no additional lubrication and until gear failure. S-gear pairs showed increased durability over the involute gear pairs. A 100% pronounced lifespan increase was observed at the tested load 0.6 Nm.