| 摘要 |
<p>A steerable drive axle (10) for a motor vehicle including a rigid tubular housing (12), a pair of steering knuckles (24A, 24B) at opposite ends of the rigid tubular housing, an expanded chamber in the middle of the rigid tubular housing open on one side (28) for access to a differential gear set in the expanded chamber, a differential cover (30) for closing the open side (28) of the expanded chamber, and an electrically-powered steering apparatus on the cover linked to the steering knuckles. The electrically-powered steering apparatus includes a rack bar passage (36) in the differential cover, a rack bar (38) supported in the rack bar passage for linear translation and linked to the steering knuckles, a pinion head (60) rotatably supported on the differential cover having a pinion gear (68) meshing with a rack gear (70) on the rack bar, an electric motor (72) mounted on the differential cover, and a speed reducer (82) on the differential cover between the pinion head and an output shaft (76) of the electric motor. In a preferred embodiment, the speed reducer consists of a pair of planetary gear sets (84A, 84B) affording double reduction torque multiplication between the electric motor and the pinion head.</p> |
