Patent ID: 7704183

Claim:
An outboard motor comprising: a drive shaft including a pinion gear arranged at one end of the drive shaft; a first driven gear engaged with the pinion gear; a second driven gear engaged with the pinion gear; a first propeller shaft connected to a second propeller; and a second propeller shaft connected to a first propeller; wherein the first driven gear is engaged with the pinion gear and with the second propeller shaft during each of forward, neutral, and reverse modes of the outboard motor, and the second driven gear is engaged with the pinion gear and with the first propeller shaft during each of the forward, neutral, and reverse modes of the outboard motor; the first propeller and the second propeller rotate in directions opposite to each other during the forward mode and during the reverse mode; the outboard motor further includes: a transmission ratio changing unit operatively connected to the drive shaft, the transmission ratio changing unit arranged to rotate the drive shaft at two different speeds; and a shift switching unit operatively connected to the drive shaft and disposed below the transmission ratio changing unit, the shift switching unit arranged to rotate the drive shaft in a first direction during the forward mode, not rotate the drive shaft during the neutral mode, and rotate the drive shaft in a second direction during the reverse mode; and the transmission ratio changing unit and the shift switching unit are housed in a rower transmission mechanism.