Exhaust system for outboard motor
AssigneeYamaha Marine Kabushiki Kaisha
InventorsYukinori Kashima, Hiroyuki Tsunekawa
Life of this patent
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Abstract
An outboard motor includes a housing unit mounted on an associated watercraft. An engine is disposed above the housing unit. The engine defines a first exhaust passage communicating with a combustion chamber of the engine. The housing unit defines a second exhaust passage communicating with the first exhaust passage. The second exhaust passage communicates with outside through at least an underwater exhaust discharge port formed at a portion of the housing unit. An air intake device communicates with either the first exhaust passage or the second exhaust passage. The air intake device includes a one-way valve that allows air to enter the first or second exhaust passage and inhibits exhaust gases from moving beyond the one-way valve.
Claims32
An outboard motor comprising a housing unit adapted to be mounted on an associated watercraft, an internal combustion engine disposed above the housing unit, the engine defining a first exhaust passage communicating with a combustion chamber of the engine, the housing unit defining a second exhaust passage communicating with the first exhaust passage, the second exhaust passage communicating with an outside of the outboard motor through an exhaust discharge port formed at a portion of the housing unit, a primary air delivery unit arranged to deliver air to the combustion chamber, the primary air delivery unit having a throttle valve, a secondary air delivery unit arranged to deliver supplemental air to the combustion chamber, the secondary air delivery unit coupled with a portion of the primary air delivery unit at a location downstream of the throttle valve, and an air intake device communicating with the secondary air delivery unit and either the first exhaust passage or the second exhaust passage, the air intake device including a one-way valve connected to the secondary air delivery unit and at least one of the first and second exhaust passages so as to allow at least a portion of the supplemental air to enter the first or second exhaust passage and to inhibit exhaust gases from moving beyond the one-way valve.
An outboard motor comprising a housing unit adapted to be mounted on an associated watercraft, an internal combustion engine disposed above the housing unit, the engine including an engine body defining a combustion chamber, a first air delivery system arranged to deliver air to the combustion chamber, the first air delivery system having a throttle valve, a second air delivery system arranged to deliver supplemental air to the combustion chamber, the second air delivery system connected to a portion of the first air delivery system at a location positioned downstream of the throttle valve, an exhaust system arranged to guide exhaust gases from the combustion chamber to outside through an exhaust discharge port formed at a portion of the housing unit, an air intake device communicating with the exhaust system and the second air delivery system, the air intake device including a one-way valve that allows a portion of the supplemental air to enter the exhaust system and inhibits the exhaust gases from moving beyond the one-way valve.
An outboard motor comprising a housing unit adapted to be mounted on an associated watercraft, an internal combustion engine disposed above the housing unit, the engine including an engine body defining a combustion chamber, an air induction system arranged to guide air to the combustion chamber, the air induction system including a plenum chamber, an exhaust system arranged to guide exhaust gases from the combustion chamber to outside through an exhaust discharge port formed at a portion of the housing unit, an air intake device communicating with the exhaust system, the air intake device including a one-way valve that allows the air to enter the exhaust system and inhibits exhaust gases from moving beyond the one-way valve, the air intake device drawing the air from the plenum chamber, the exhaust discharge port including first and second outlets, the first outlet being submerged when the outboard motor is in a propelling position of the associated watercraft, the second outlet being not submerged when the outboard motor is in the propelling position of the associated watercraft, the exhaust system being divided into first and second sections, the first section being connected to the first outlet, the second section being connected to the second outlet, the air intake device being connected to the second section.
An outboard motor comprising a housing unit adapted to be mounted on an associated watercraft, an internal combustion engine disposed above the housing unit, the engine defining a combustion chamber therein, a first air delivery system arranged to deliver air to the combustion chamber, the first air delivery system having an air regulating device, a second air delivery system arranged to deliver supplemental air to the combustion chamber, the second air delivery system communicating with a portion of the first air delivery system at a location downstream of the regulating device, an exhaust system arranged to guide exhaust gases from the combustion chamber to outside through an exhaust discharge port formed at a portion of the housing unit, and means for delivering a portion of the supplemental air to the exhaust system when the exhaust system generates negative pressure.
An outboard motor comprising a housing unit adapted to be mounted on an associated watercraft, an internal combustion engine disposed above the housing unit, the engine including an engine body defining a combustion chamber, an air induction system arranged to guide air to the combustion chamber, an exhaust system arranged to guide exhaust gases from the combustion chamber through an exhaust discharge, an air intake device communicating with the exhaust system, the air intake device including a one-way valve that allows the air to enter the exhaust system and inhibits exhaust gases from flowing through the one-way valve, the exhaust discharge including first and second outlets, the first outlet being submerged when the outboard motor is in a propelling position, the second outlet being above the water surface when the outboard motor is in the propelling position, the exhaust system being divided into first and second sections, the first section communicating with the first outlet, the second section communicating with the second outlet, the air intake device being connected to the second section.
An outboard motor comprising an internal combustion engine that has a combustion chamber, a first air delivery system that delivers air to the combustion chamber, the first air delivery system having an air regulating device, a second air delivery system that delivers supplemental air to the combustion chamber, the second air delivery system communicating with a portion of the first air delivery system at a location downstream of the regulating device, an exhaust system that routes exhaust gases from the combustion chamber, and a third air delivery system that delivers a portion of the supplemental air to the exhaust system when the exhaust system generates a negative pressure.
An outboard motor comprising internal combustion engine that has an engine body, the engine body defining a combustion chamber, a first air delivery system that delivers air to the combustion chamber, the first air delivery system having at least one plenum chamber disposed generally on a first side of the engine body, an exhaust system that routes exhaust gases from the combustion chamber, and a second air delivery system that delivers air to the exhaust system when the exhaust system generates a negative pressure, the second air delivery system not receiving the air supplied to the exhaust system from the first air delivery system.
Dependencies are inferred from the claim text.