Transmission

A transmission comprising a first shaft unit connected to a drive shaft of a drive unit,

• wherein the first shaft unit includes:
• a first shaft connected to the drive shaft, the first shaft including a first shaft raceway surface that is formed by a groove extending in a circumferential direction on an outer peripheral surface of the first shaft;
• a first output gear provided on the first shaft and configured to rotate integrally with the first shaft;
• a first outer ring attached to a first support part supporting the first shaft and provided so as to surround the first shaft raceway surface, the first outer ring including a first outer ring raceway surface on an inner peripheral surface thereof;
• and
• a plurality of ball-shaped first rolling elements disposed between the first shaft raceway surface and the first outer ring raceway surface,
• wherein the groove forming the first shaft raceway surface has a pair of groove edge parts extending in the circumferential direction of the outer peripheral surface of the first shaft,
• wherein the groove edge part on a side closer to the first output gear has a diameter larger than a diameter of the other groove edge part,
• wherein the first rolling elements, the first shaft raceway surface, and the first outer ring raceway surface constitute a deep groove ball bearing, and
• wherein a load point between the first rolling element and the first shaft raceway surface and a load point between the first rolling element and the first outer ring raceway surface are positioned on a line perpendicular to the first shaft.