Outboard motor
An outboard motor includes a first housing, a second housing, a propeller shaft, and a steering mechanism. The steering mechanism includes a first pinion gear, a second pinion gear, a first rack, and a second rack. The first pinion gear is connected to the first housing or the second housing. The second pinion gear is connected to the first pinion gear. The first rack includes first teeth. The first teeth mesh with the first pinion gear and are arranged side by side with each other in a first direction. The first rack is movable in the first direction. The second rack includes second teeth. The second teeth mesh with the second pinion gear and are arranged side by side with each other in a second direction. The second teeth have a smaller module than the plurality of first teeth. The second rack is movable in the second direction.
1. An outboard motor comprising:
a first housing;
a second housing supported by the first housing and steerable around a steering axis;
a propeller shaft in the second housing and extending in a front-rear direction of the outboard motor; and
a steering mechanism to steer the second housing around the steering axis, the steering mechanism including:
a first pinion gear connected to the first housing or the second housing;
a second pinion gear connected to the first pinion gear;
a first rack including a plurality of first teeth that mesh with the first pinion gear and arranged side by side with each other in a first direction, the first rack being movable in the first direction; and
a second rack including a plurality of second teeth that mesh with the second pinion gear, arranged side by side with each other in a second direction, and have a smaller module than the plurality of first teeth, the second rack being movable in the second direction.
2. The outboard motor according to claim 1 , wherein a length of the second rack in the second direction is smaller than a length of the first rack in the first direction.
3. The outboard motor according to claim 1 , wherein
in a case where a steering angle of the second housing is in a first range, the first rack is movable in the first direction to rotate the first pinion gear and steer the second housing; and
in a case where the steering angle of the second housing is in a second range that is larger than the first range, the second rack is movable in the second direction to rotate the second pinion gear and steer the second housing.
4. The outboard motor according to claim 3 , wherein
the first rack includes a first relief portion; and
in a case where the steering angle of the second housing is in the second range, the first relief portion faces the first pinion gear to allow the first pinion gear to idle with respect to the first rack.
5. The outboard motor according to claim 1 , further comprising a first hydraulic actuator to move the first rack in the first direction.
6. The outboard motor according to claim 1 , further comprising a second hydraulic actuator to move the second rack in the second direction.
7. The outboard motor according to claim 6 , wherein
in a case where the steering angle of the second housing is in a first range, the first rack is movable in the first direction to rotate the first pinion gear and steer the second housing;
in a case where the steering angle of the second housing is in a second range that is larger than the first range, the second rack is movable in the second direction to rotate the second pinion gear and steer the second housing; and
in a case where the steering angle of the second housing is in the first range, the second hydraulic actuator is operable to release hydraulic pressure to the second rack to allow the second rack to move in the second direction.
8. The outboard motor according to claim 1 , wherein the first direction is the front-rear direction of the outboard motor.
9. The outboard motor according to claim 1 , wherein the second direction is the front-rear direction of the outboard motor.