EXPERIMENTAL AND NUMERICAL INVESTIGATION OF THE MESHING CYCLE AND CONTACT RATIO IN SPIRAL BEVEL GEARS

The load carrying capacity of spiral bevel gears is governed by the wa y load is distributed between meshing tooth pairs, which is highly dep endent on the actual contact ratio as the gears mesh. Previous experim ental studies have shown that the AGMA calculated contact ratio is sub stantially different from that found in practice, because of the shape and dimensions of the bearing pattern produced by the load transmitte d between meshing gear teeth. Given the geometrical complexity of spir al bevel gear tooth profiles, a Tooth Contact Analysis computer progra m is used to determine the location of the path of contact, the dimens ions of the bearing pattern under load and the associated contact rati o. The objectives of this paper are to experimentally and numerically study the relationships between the bearing pattern of selected spiral bevel gear sets and their load meshing cycles, to evaluate the actual contact ratio, and to calculate and compare the corresponding AGMA co ntact ratio to measurements and values calculated by a Loaded Tooth Co ntact Analysis computer program. (C) 1998 Elsevier Science Ltd.