Patent ID: 8517782
Filing Date: 2013-08-27
Classification: B63H

Abstract:
1. A marine vessel propulsion device comprising: an engine including a throttle valve arranged to open and close an air intake passage; a jet propulsion unit driven by the engine, the jet propulsion unit including a jet port arranged to jet water to a rear of a hull, and to change a direction of the water jetted from the jet port to right and left; a reverse gate arranged to change in opening degree between a fully closed position of covering an entirety of the jet port when the jet port is viewed from a jetting direction of the jet propulsion unit and a fully opened position of not covering the jet port at all, and arranged so that at the fully closed position the water jetted from the jet port is guided toward a front of the hull; a steering device arranged to be operated by an operator to change the direction of the water jetted by the jet propulsion unit to the right and the left; a lever arranged to be operated by the operator to set an opening degree of the throttle valve of the engine and the opening degree of the reverse gate, and arranged to be moved in the order of a maximum output forward drive position, to a gate fully opened position, to a forward drive starting position, to a neutral position, to a reverse drive starting position, and to a maximum output reverse drive position; a lever position keeping unit arranged to keep the lever at the forward drive starting position, the neutral position, and the reverse drive starting position, respectively; a throttle opening degree operating unit that increases the opening degree of the throttle valve in conformance to an operation amount of the lever from the gate fully opened position when the lever is between the gate fully opened position and the maximum output forward drive position, increases the opening degree of the throttle valve in conformance to the operation amount of the lever from the reverse drive starting position when the lever is between the reverse drive starting position and the maximum output reverse drive position, fixes the opening degree of the throttle valve at a predetermined first opening degree when the lever is between the reverse drive starting position and the forward drive starting position, and sets the opening degree to no less than the first opening degree when the lever is between the forward drive starting position and the gate fully opened position; and a reverse gate keeping unit including a control unit that keeps the reverse gate at the fully opened position when the lever is positioned in a range from the gate fully opened position to the maximum output forward drive position, keeps the reverse gate at the fully closed position when the lever is positioned in a range from the reverse drive starting position to the maximum output reverse drive position, keeps the reverse gate at a first partially closed position of only partially covering the jet port when the lever is positioned at the neutral position, and keeps the reverse gate at a second partially closed position of only partially covering the jet port and being closer to the fully opened position than the first partially closed position when the lever is positioned at the forward drive starting position; wherein the throttle opening degree operating unit controls the throttle valve to be set at the first opening degree when the lever is positioned in a range from the forward drive starting position to the gate fully opened position.