Marine propulsion – Means for accomodating or moving engine fluids – Cooling for engine
Reexamination Certificate
1998-03-02
2001-06-12
Morano, S. Joseph (Department: 3617)
Marine propulsion
Means for accomodating or moving engine fluids
Cooling for engine
Reexamination Certificate
active
06244915
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates in general to an engine, and in particular to a fuel system and arrangement for a marine engine.
2. Description of Related Art
Personal watercraft have become popular in recent years. This type of watercraft is sporty in nature; it turns swiftly, is easily maneuverable, and accelerates quickly. Personal watercraft today commonly carry one rider and one or two passengers.
A relatively small hull of the personal watercraft commonly defines a rider's area above an engine compartment. An internal combustion engine frequently powers a jet propulsion unit which propels the watercraft. A plurality of engine mounts support the engine within the engine compartment in front of a tunnel formed on the underside of the watercraft. The jet propulsion unit is located within the tunnel and is driven by a drive shaft connected to the engine.
Personal watercraft often employ an inline, multi-cylinder, crankcase compression, two-cycle engine. The engine conventionally lies within the engine compartment with the in-line cylinders aligned along a longitudinal axis of the watercraft hull. An exhaust system communicates with the cylinders of the engine and extends to a discharge that is located near the stem of the watercraft. In this manner, exhaust gases are expelled from the watercraft's and the engine compartment.
Air must be supplied to the engine from outside the hull for use in the combustion process. Typically, air flows through one or more ducts in the hull into the engine compartment, and then through an intake system of the engine to combustion chambers of the engine.
Fuel is also supplied to the engine for use in the combustion process. In order to accurately meter the fuel and improve engine operating efficiency and performance, fuel injectors can be used to inject fuel into the combustion chambers or to form a fuel/air charge before such charge enters the combustion chambers. Each injector has an electrically-operated valve which selectively opens and closes, controlling the flow of fuel through the injectors to the engine. Typically, a high pressure fuel pump is used to supply pressurized fuel to each fuel injector via a fuel rail. The fuel system continuously supplies fuel from a fuel tank to the fuel injectors while returning excess fuel to the fuel tank through a return line.
In order to keep the size of the watercraft small and center of gravity low, the engine compartment is made very small, thus necessitating that the engine be compact. One problem with this arrangement is that hot exhaust gases flowing through the exhaust system may be routed very close to other components of the engine, damaging them or resulting in their poor performance. This is true for the fuel pump where the heat from the exhaust system may damage the fuel pump or shorten its useful life. Elevation of the fuel temperate within the delivery and return lines, as well as within the fuel pump, can also affect the fuel air ratio of the charge formed by the fuel injectors.
Some prior watercraft have increased the width of the watercraft in order to separate the fuel supply system from the exhaust system. Such watercraft, however, sacrifice the handling performance of the watercraft due to the resulting wider hull; the wider hull can not turn as sharp.
Moreover, the associated engines have also employed a wider width in order to provide a component arrangement wherein the position of the fuel rail is positioned on one side of the engine, away from the exhaust system, in a suspended position. However, due to the sporty nature of the watercraft, the fuel supply pipe experiences vigorous impact as the watercraft jumps and lands when speeding across the body of water in which it is operated. The high pressure fuel supply pipe thus can be damaged when supported in this position and directly mounted to the hull.
SUMMARY OF THE INVENTION
One aspect of the present invention involves arranging the components of the fuel supply system to provide a compact engine while promoting air cooling of at least a portion of the fuel supply system. In one mode, the small watercraft has a hull defining an engine compartment. An internal combustion engine is located within the engine compartment and drives a propulsion device carried by the hull. At least one air duct communicates with the engine compartment through at least one outlet opening. An induction system is connected to the engine and includes an air inlet. A fuel supply system includes a fuel delivery line and a fuel return line that communicate with a fuel tank and together define a fuel loop. A fuel rail communicates with the fuel loop and with a plurality of fuel injectors mounted in the engine, and the fuel delivery and return lines are arranged within the hull of the watercraft such that at least a portion of one of the lines extends between the air duct outlet end and the air inlet of the induction system. In this manner, at least a portion of the fuel supply system is air cooled in order to position portions of the fuel supply system in relatively close proximity to the engine's exhaust system while reducing the effect of heat on the fuel supply system.
An additional aspect of the present invention involves reducing the impact experienced by at least some components of the fuel supply system when the watercraft skips over the body of water on which is it planing. In one mode, the small watercraft comprises a hull defining a rider's area behind a bow of the hull. The rider's area is sized to accommodate at least one rider. An internal combustion engine is located in an engine compartment defined within the hull. The engine includes an output shaft that drives a drive shaft of a propulsion device of the watercraft, and a fuel supply system. The fuel supply system includes a fuel tank connected to a fuel delivery line and to a fuel return line that together define a fuel loop. A fuel pump communicates with the fuel loop and is mounted on the engine. A fuel rail communicates with the fuel pump and with a plurality of fuel injectors mounted in the engine. At least a portion of the fuel delivery line and/or the fuel pump is coupled to the hull by a plurality of shock-absorbent mounts that lie between the hull and these components of the fuel system. The mounts reduce the amount of shock experienced by the fuel pump and/or a portion the fuel delivery line as the watercraft bounces across the body of water when in use. In a more preferred mode, the mounts are engine mounts that support the engine within the engine compartment of the watercraft hull.
Further aspects, features, and advantages of the present invention will become apparent from the detailed description of the preferred embodiments which follow.
REFERENCES:
patent: 3948206 (1976-04-01), Tyler
patent: 4416638 (1983-11-01), Ellis
patent: 5022355 (1991-06-01), Billingsley et al.
patent: 5197436 (1993-03-01), Ozawa
patent: 5231958 (1993-08-01), Takahashi et al.
patent: 5241931 (1993-09-01), Radel
patent: 5259352 (1993-11-01), Gerhardy et al.
patent: 5353760 (1994-10-01), Zager
patent: 5367998 (1994-11-01), Shiohara et al.
patent: 5429095 (1995-07-01), Aodai et al.
patent: 5732685 (1998-03-01), Nakamura
patent: 5902158 (1999-05-01), Nakase et al.
patent: 6015321 (2000-01-01), Ozawa et al.
Knobbe Martens Olson & Bear LLP
Morano S. Joseph
Wright Andrew
Yamaha Hatsudoki Kabushiki Kaisha
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