Patent ID: 9651137
Date: 2017-05-16
CPC Classifications: F16H

Claim:
1. A lubrication structure for a differential device including a differential case rotatably disposed inside a transmission case and having an inboard section rotatably supporting an axle, and a final driven gear on the differential case, the lubrication structure comprising: a bearing rotatably supporting the differential case to the transmission case; an oil seal between the transmission case and the axle; a lubrication oil guide groove on an inner surface of the transmission case, the lubrication oil guide groove communicating between the bearing and the oil seal; and a spiral oil groove on an inner periphery of the inboard section from an opening end of the inboard section toward a center in an axial direction of the differential device, wherein lubrication oil pumped up in the transmission case by the final driven gear and then flowed from the lubrication oil guide groove in between the bearing and the oil seal is supplied from the opening end of the inboard section to the spiral oil groove, wherein the opening end of the inboard section comprises: an end surface perpendicular to the axial direction at a position farthest from the center in the axial direction; a ledge positioned closer to the center in the axial direction than the end surface at a position adjacent to the end surface in a circumferential direction of the opening end; and a tapered section continuing to an inner diameter side of the ledge of the opening end, slanting toward an inner diameter side of the opening end and approaching the center, and wherein lubrication oil supplied from the lubrication oil guide groove to the opening end of the inboard section flows via the ledge to the tapered section and then from the tapered section into the spiral oil groove.