US 5,701,855 AGranted

Cartridge fuel internal combustion engine

AssigneeRyobi Ltd.

InventorsKatsumi Kurihara, Shiro Kawamoto, John E. Nemazi, William G. Conger

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Abstract

An internal combustion engine is provided with a cartridge containing a fuel/oil mixture where the fuel is liquid, normally gaseous fuel. The cartridges can be readily mounted or demounted from the engine, and provide flexibility of use coupled with easy starting. The use of the fuel/oil cartridges eliminates the need to separately mix oil and fuel, and eliminates substantial contact of the user with an oily fuel/oil mixture. The two cycle and four cycle cartridge-type engines are suitable for use in many hand-powered implements, including line trimmers, chain saws, leaf blowers, hedge trimmers, etc.

Claims20

Dependent claims

A two-cycle engine assembly of the type having a crankcase through which combustible air/fuel/oil mixture flows prior to introduction into a combustion chamber of the engine, the two-cycle engine assembly comprising:

a crankcase assembly having a crankcase housing forming an enclosed crankcase chamber, the crankcase housing surrounding a crankshaft pivotally mounted thereto;
a piston and connecting rod;
a cylinder assembly affixed to the crankcase housing and having a cylinder wall and enclosed end to define a combustion chamber in cooperation with the piston, the piston sealingly cooperating with the cylinder wall and reciprocally movable thereby by the connecting rod which pivotally attaches the piston to the crankshaft causing the piston to reciprocate as the crankshaft rotates, the cylinder assembly having an inlet extending through the cylinder wall to introduce the air/fuel/oil mixture into the crankcase chamber and a transfer passageway connecting the crankcase chamber to the combustion chamber to allow air/fuel/oil mixture to be displaced from the crankcase chamber to the combustion chamber, the cylinder assembly further provided with an exhaust port extending through the cylinder wall to facilitate the removal of post-combustion exhaust gases;
a connector having an inlet for receiving a pressurized cartridge containing the mixture of liquid normally gaseous fuel and oil, and an outlet for the fuel/oil mixture;
a pressure regulator cooperating with the connector outlet for providing the fuel/oil mixture at a controlled pressure;
a carburetor coupled to the inlet of the cylinder assembly for mixing the fuel/oil mixture supplied by the pressure regulator with air at a predetermined ratio throughout a range of flow conditions associated with normal engine operation;
wherein the air/fuel/oil mixture lubricates necessary portions of the two cycle engine assembly prior to introduction into the combustion chamber of the engine.

4 more elements

A four cycle engine assembly, comprising:

an engine block forming a cylindrical bore, an enclosed crankcase in communication with the cylindrical bore;
a piston reciprocally cooperating within said cylindrical bore;
a connecting rod assembly having a first bearing for pivotally cooperating with the piston, an elongated central region, and a second bearing spaced from the first bearing;
a crankshaft having a crankpin cooperating with the connecting rod second bearing, an elongated axial shaft pivotally mounted upon the engine block bearing journal and provided with a drive end, an output end, and a web counterweight;
a cylinder head assembly attached to the engine block to define a combustion chamber in cooperation with the cylinder bore and the piston, said cylinder head assembly having an intake port and an exhaust port;
a spark plug hole extending into the combustion chamber and an intake valve;
an exhaust valve and a spark plug, respectively cooperating with the intake and exhaust ports and spark plug hole;
a cam shaft driven by the crankshaft at 1/2 engine speed for sequentially activating the intake and exhaust valves;
optionally, a valve cover attached to the cylinder head to define a valve chamber;
a connector having an inlet for receiving a pressurized cartridge containing a mixture of liquid normally gaseous fuel and oil, and an outlet for the fuel/oil mixture;
a pressure regulator cooperating with the connector outlet for providing the fuel/oil mixture at a controlled pressure;
a carburetor for mixing the fuel/oil mixture with air at a predetermined ratio throughout a range of flow conditions associated with normal engine operation;
wherein the fuel/oil mixture supplied by the pressure regulator lubricates necessary portions of four cycle engine assemblies prior to introduction into the combustion chamber of the engine.

10 more elements

Dependencies are inferred from the claim text.