摘要 |
A differential apparatus includes a differential casing, a pair of helical side gears and a pairs of helical pinion gears. The helical pinion gears are accommodated in bores formed in the differential casing, respectively. When it is expected that a helix angle of tooth trace of the helical pinion gear would be decreased by the vehicle's driving, one of the helical pinion gears is formed in advance so that the tooth depths are gradually decreased from axial ends of the helical pinion gear toward the axial intermediate potion. Conversely, when it is expected that a helix angle of tooth trace of the pinion gear would be increased by the vehicle's driving, one of the helical pinion gears is formed in advance so that the tooth depths are gradually increased from the axial ends of the helical pinion gear toward the axial intermediate potion. With the arrangement, even if the helical pinion gears are slanted, the helical pinion gear can be in uniform contact with the bore over the whole tooth width, so that it is possible to prevent an occurrence of the eccentric abrasion and seizure.
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