| 摘要 |
<p>This face gear has a plurality of annularly arranged gear teeth (8). A recess (10) for holding grease or another lubricant is formed in the tooth surface (9) of each gear (8). A recess formation area (alpha), which is the area in which the recess (10) is formed, is provided to the tooth bottom (8b) side in relation to the pitch point (P) in each gear tooth (8). In other words, a recess (10) is not formed in the portion of the tooth surface (9) on the tooth tip (8a) side from the pitch point (P). As a result, the gear teeth can be effectively lubricated while minimizing instability in the meshing state between gears.</p> |
