Farm Power And Machinery (1+1)

Working of I.C. Engine

• In IC engine the piston which is reciprocating in the cylinder is tight fit in the cylinder. Rings are inserted in the circumferential grooves of the piston to prevent leakage of gases from sides of the piston. Usually a cylinder is bored in a cylinder block and a gasket, made of copper sheet or asbestos is inserted between the cylinder and the cylinder head.
• The combustion space is provided at the top of the cylinder head where combustion takes place. There is a rod called connecting rod for connecting the piston and the crankshaft. A pin called gudgeon pin or wrist pin is provided for connecting the piston and the connecting rod of the engine. The end of the connecting rod which fits over the gudgeon pin is called small end of the connecting rod.
• The other end which fits over the crank pin is called big end of the connecting rod. The crankshaft rotates in main bearings which are fitted in the crankcase. A flywheel is provided at one end of the crankshaft for smoothening the uneven torque, produced by the engine. In I.C. engine the connecting rod converts the reciprocating motion of piston into rotary motion of the crankshaft. There is an oil sump at the bottom of the engine which contains lubricating oil for lubricating different parts of the engine.

The cycle of internal combustion engine can be completed in two ways:
a. When the cycle is completed in two revolutions of the crankshaft or four strokes of the piston, it is called four stroke cycle engine.
b. When the cycle is completed in one revolution of the crankshaft or two strokes of the piston, it is called two stroke cycle engine.