Internal-combustion engines – Frame construction – Horizontal cylinder
Reexamination Certificate
2001-02-28
2003-09-30
Argenbright, Tony M. (Department: 3747)
Internal-combustion engines
Frame construction
Horizontal cylinder
C123S041080, C123S1960CP, C440S012500
Reexamination Certificate
active
06626140
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates generally to a new engine for use in, for example, personal watercraft. In particular, the present invention relates to a new four-stroke in-line engine that was developed with a view to the future stricter environmental and emission regulations. The engine has a power take off assembly located on one end for housing a plurality of engine components. This arrangement locates most of the engine component connections within a single housing. Furthermore, the connection assembly within the power take off housing permits the operation of multiple engine components with a single connection to the engine crankshaft.
BACKGROUND OF THE INVENTION
There is a very popular type of watercraft known as a “personal watercraft” which is designed to be operated primarily by a single rider. Although this type of watercraft is commonly employed for single riders, frequently provisions are made for accommodating additional passengers although the maximum number of passengers is more limited than conventional types of watercraft.
This type of watercraft is also generally quite sporting in nature and normally accommodates at least the rider on a type of seat in which the rider sits in a straddle fashion. The passenger's area is frequently open through the rear of the watercraft so as to facilitate entry and exit of the rider and passengers to the body of water in which the watercraft is operating, as this type of watercraft is normally ridden with passengers that are wearing swimming suits.
These personal watercraft are generally quite small so that they can be conveniently transported from the owner's home to a body of water for its use. Because of the small size, the layout of the components is extremely critical, and this gives rise to several design considerations that are peculiar to this type of watercraft. However, due to its sporting nature, it is also desirable that the watercraft be powered by an engine and propulsion device that is not only efficient but also generates sufficient power.
Traditionally, two-cycle engines have been used to power watercraft, including personal watercraft. These engines have the advantage that they are fairly powerful, relatively lightweight, and compact.
One particular disadvantage to the two-cycle engine is its emission content. Two-cycle engines generally exhaust larger quantities of hydrocarbons and other pollutants than four-cycle engines due to cylinder charging inefficiencies and the combustion of lubricating oil among other things. When measures are taken to reduce emissions of the two-cycle engine, other generally undesirable consequences can result, such as an increase in the weight of the engine, a reduction of its power output or the like. With concern for the environment and increasingly strict emissions requirements being instituted by various governing bodies. There is motivation to provide a power plant that reduces exhaust emissions while retaining other advantageous characteristics such as compactness, low weight and high power output.
Four-cycle engines are commonly used as power plants in other applications, such as automobiles. These engines have the advantage that their emissions output are generally desirably lower as compared to a two-cycle engine for a given power output.
Four-cycle engines are generally larger than two-cycle engines and present numerous design problems when locating the engine in a relatively small personal watercraft. These engines typically include starter assemblies, generators, cam shafts, etc. There, however, is no centralized location for interconnecting these elements, which leads to larger engine sizes and a greater potential for water penetration in water environments
OBJECTS OF THE INVENTION
It is an object of the present invention to provide a four stroke, in-line engine having a compact construction.
It is another object of the present invention to provide a four stroke, in-line engine having a modular construction to permit the interchange of parts between various engine models.
It is another object of the present invention to provide a four stroke, in-line engine having improved exhaust emission characteristics.
It is another object of the present invention to provide a four stroke engine having a narrow and low profile.
It is another object of the present invention to provide a four stroke engine having a low profile valve actuation assembly for controlling the operation of the intake and exhaust valves.
It is another object of the present invention to provide a cylinder head having a low profile to reduce engine height.
It is another object of the present invention to offset the placement of the intake valves and exhaust valves with respect to a vertical axis within the cylinder head to reduce engine height.
It is another object of the present invention to provide an improved spark plug mounting assembly for easy access within the cylinder head.
It is another object of the present invention to provide a Y-shaped intake rocker arm assembly providing a compact construction.
It is yet another object of the present invention to provide a four stroke engine having an improved oil collection system and oil holding tank.
It is another object to provide a four stroke engine which combines a closed loop cooling system and an open loop cooling system for enhanced cooling of the engine in accordance with the present invention.
It is another object to provide an open loop cooling system for cooling an exhaust manifold in accordance with the present invention, wherein the open loop cooling system enhances cooling of the crankcase and cylinder head.
It is another object to provide an open loop cooling system for cooling an exhaust manifold in accordance with the present invention, wherein the open cooling system lowers the temperature of the exhaust manifold such that the exhaust manifold functions as a heat sink for the crankcase and cylinder head.
It is another object of the present invention to provide a closed loop cooling system for selectively cooling the crankcase and cylinder head of the four stroke engine.
It is another object of the present invention to provide a closed loop cooling system having a selectively operable heat exchanger.
It is another object of the present invention to provide a supercharger for enhanced engine performance.
SUMMARY OF THE INVENTION
In accordance with the present invention, a four stroke internal combustion engine is disclosed having a power take off housing located at one end of the engine. The engine includes a crankcase having a crankshaft that is rotatably mounted therein. The crankshaft extends from one end of the crankcase. A cylinder head is connected to the crankcase. The crankcase and the cylinder head form at least one cylinder. Each cylinder includes at least one intake valve and at least one exhaust valve. A valve actuation assembly is located in the cylinder head and operates the intake and exhaust valves. A cam shaft is located in the cylinder head and operatively connected to the valve actuation assembly. In accordance with the present invention, the crankshaft is operatively connected to a drive shaft and the cam shaft. Furthermore, the crankshaft is operatively coupled within the power take off housing to at least one of a generator, an engine starting mechanism, a balance shaft, and a supercharger.
In accordance with the present invention, the connecting assembly connects the crankshaft to the drive shaft. The connecting assembly includes a connecting sleeve connected between an end of the crankshaft and an end of the drive shaft. The one end of the connecting sleeve is threadably connected to one of the crankshaft and the drive shaft. Another end of the connecting sleeve includes a plurality of teeth for engaging the other of the crankshaft and the drive shaft. The plurality of teeth engage at least one arcuate tooth on one of the crankshaft and the drive shaft. The teeth are lubricated by the engine lubrication system. The lubricant may be fed through a passageway in the crankshaft.
The cranks
Aichinger Manfred
Holzleitner Johann
Sonnleitner Michael
Tscherne Rudolf
Wolfsgruber Alois
Argenbright Tony M.
Bombardier-Rotax GmbH
Harris Katrina B.
Pillsbury & Winthrop LLP
LandOfFree
Four stroke engine having power take off assembly does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Four stroke engine having power take off assembly, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Four stroke engine having power take off assembly will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3112570