need to increase engine thermal efficiency. The four strokes employed are intake stroke, compression stroke, expansion stroke, and exhaust stroke. In addition to these four strokes,this invention adds a secondary process having two additional strokes for scavenging the combustion chamber with fresh air. This additional two stroke scavenging process employs a fresh air intake stroke and a fresh air exhaust stroke to expel remaining gases.
Working of the apparatus
The overall cycle of thi sengine comprises the four strokes of a normal four stroke internal combustion engine including an intake stroke, compression stroke, expansion stroke and exhaust stroke;in which output power is generated, and a second scavenging process having two strokes, which is performed after these four strokes.The new two strokes introduced does the following:
1)intake stroke which introduces only air into the combustion chamber
2)exhaust stroke in which the remaining burnt gas in the combustion chamber is scavenged which otherwise, during the subsequent compression stroke inhibits the propagation of flame through the charge mixture due to residual gases.
In this apparatus, the cam shaft of the IC Engine is provided with an additional lobe on each cam which is rotated at a rate of one-third that of the crankshaft so that one complete cycle of the first process and second process is performed on every three revolutions of the crankshaft.Thus we have the intake cam and th eexhaust cam. The intake stroke of the first process and intake air stroke of the second scavenging process is achieved by separate lobes of the intake cam.And the exhaust stroke of the first process and the exhaust air stroke of the scavenging process are performed by separate lobes of the exhaust cam. The intake charge is recieved through i carburetor . the carburetor has two tracts:
1) primary tract through which air/fuel mixture is supplied during the intake stroke,
2)secondary tract through which fresh air is supplied during the air intake stroke of the second process.The operation of this tract is done by a solenoid valve responsive to the rotation of the cam shaft which controls the operation of the secondary tract to supply fresh air to the combustion chamber. This is accomplished through the use of an air flow controlling piston which controls the amount of air flow through the secondary fresh air flow passage in response to the temperature of the engine. Temp of engine is constantly tracked by temperature sensing washer installed under the spark plug. Due to this control mechanism, as the temperature of the engine increases, the amount of air flow through the engine is increased to cool the