On the Measurement of Temperature Flashes on Spur Gear Teeth : 1st Report, The Case of Meshing with a Pair of Ground Standard Gears

Abstract

As a basic experiment on gear scoring, the surface temperatures of gear teeth are measured. So far, we can find the experiment for measuring the mean surface temperatures of gear teeth. But it is significant in considering a countermeasure of scoring that from another point of view we know the change of the instantaneous temperature with the change of the meshing position. In our experiment the thermocouple consisted of a constantan pinion and a steel wheel, and the thermoelectricity produced in it was observed by oscilloscope. As a result we reached the following conclusion : (1) On the relation between the meshing position and the surface temperature of gear teeth, the experimental value is nearly equal to the value calculated theoretically. (2) As the surface temperature of gear teeth is largely influenced by the load distribution, it is most desirable for designing the gear that we try to change the profile of gear teeth so that the surface temperature may be minimum, and to avoid the local contact of gears. (3) The surface temperature of gear teeth rises in proportion to the circumferential speed of gears in the range of lower speeds, but in the range of higher speeds its change becomes small. Speaking of the influence of loads, the temperature changes in proportion to 1/2 the power of the load, but in the range of higher speeds the change becomes small.