Transmission

A transmission comprising:

• a first shaft to which power is inputted;
• a second shaft that is disposed along the first shaft;
• a plurality of transmission gears that each have a drive gear disposed on the first shaft and a driven gear disposed on the second shaft, the drive gear and the driven gear engaging each other, wherein the drive gear is relatively rotatable with respect to the first shaft or the driven gear is relatively rotatable with respect to the second shaft;
• a plurality of hubs that are each disposed on the first shaft so as to be aligned with the drive gear or on the second shaft so as to be aligned with the driven gear and that are each relatively unrotatable with respect to the first shaft or the second shaft;
• a clutch ring that is mounted on each of the hubs so as to be relatively movable in the axial direction, that interlocks the drive gear or the driven gear with the hub at a first position in the axial direction, and that moves from the first position to a second position in the axial direction to separate the drive gear or the driven gear and the hub from each other;
• and
• an operating portion that moves the clutch ring in the axial direction,
• wherein one of the hub and the clutch ring has a protrusion that protrudes in the radial direction,
• wherein the other of the hub and the clutch ring has a groove portion in which the protrusion relatively moves in the rotational direction and in the axial direction,
• wherein the groove portion has a first wall and a second wall that is opposite to the first wall in the rotational direction, the second wall and the first wall abutting on the protrusion to integrally rotate the hub and the clutch ring,
• wherein the first wall has a first portion that inclines with respect to the axial direction and that generates a force in the axial direction from the first position toward the second position in the protrusion,
• wherein the first wall has a first retaining portion that is joined to the first portion and that prevents relative movement of the protrusion from the first position toward the second position during coasting in which power is transmitted from the driven gear to the drive gear, and
• wherein an angle θ1 between a plane parallel to an axis and the first retaining portion is set to 0°<θ1≤90°.