Patent ID: 8568178
Filing Date: 2013-10-29
Classification: B63H

Abstract:
1. A marine vessel propulsion apparatus comprising: an engine including a rotatably arranged crankshaft, the engine arranged to rotate a propeller by rotating the crankshaft in one rotation direction; a rotation speed detecting device arranged to detect a rotation speed of the crankshaft; a forward-reverse switching mechanism arranged to transmit the rotation of the crankshaft to the propeller, the forward-reverse switching mechanism arranged to be switched among a forward drive state in which the propeller is rotated in a forward drive rotation direction, a reverse drive state in which the propeller is rotated in a reverse drive rotation direction, and a neutral state in which a transmission of rotation between the crankshaft and the propeller is cut off; a shift position detecting device arranged to detect which state among the forward drive state, the reverse drive state, and the neutral state the forward-reverse switching mechanism is in; a liquid supplying device arranged to be driven by the engine and to supply a liquid to the engine; a flow passage arranged to be supplied with the liquid from the liquid supplying device when the crankshaft is rotating in the one rotation direction; a physical quantity detecting device arranged to detect, in the flow passage, a physical quantity of the liquid supplied from the liquid supplying device to the flow passage; and a controller arranged to acquire detection values of the rotation speed detecting device, the shift position detecting device, and the physical quantity detecting device, the controller executes a reverse rotation prevention control to control at least one of either the engine or the forward-reverse switching mechanism to prevent reverse rotation of the crankshaft in a case where a post-switching physical quantity, which is the physical quantity of the liquid in the flow passage after the forward-reverse switching mechanism has been switched from the forward drive state to the reverse drive state in a state where the crankshaft is rotating, is less than a predetermined first value.