Mechanical Motion

There are a great many forms of motion. An incalculable number of bodies are in motion on the earth, which in its turn is rotating about its axis and also travelling around the sun, while the sun itself and all its planets are in movement relative to the stars, which in their turn are also moving through space. But in all these instances we have to do with only one form of motion - the motion of bodies themselves. Science has established that heat light, electricity, and chemical and many other phenomena are also forms of motion. Furthermore life itself in all its manifestations is а form of motion.

The perpetual movement of matter causes all natural phenomena about us.

Motion occurs in space and in time, therefore space and time are inseparable from matter in motion. When a body changes its position in respect to other bodies, we say it is in motion. Thus relative change in position of a body is called "mechanical motion".

The science dealing with the laws of mechanical motion is called "mechanics".

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C arburettor Engine- карбюраторний двигун

1 — fan belt ремінь вентилятора; 2 — generator генератор; 3 — fan вентилятор; 4 — piston pin поршневий палець; 5 — small end of connecting rod верхня головка шатуна; 6 — water jacket водяна рубашка; 7 — spark plug свічка запалювання; 8 — cylinder циліндр; 9 — piston поршень; 10 — poppet-valve тарільчатий клапан; 11 — exhaust manifold вихлопний збірник; 12 — inlet manifold всмоктуючий коллектор; 13 — flywheel маховик; 14 — main bearing ко­рінний підшипник; 15 — oil pan піддон картера; 16 — crankshaft колінчатий вал; 17 — camshaft розпредільний вал; 18 — cam кулачок; 19 — tappet толкатель; 20 — big end of connecting rod нижня головка шатуна; 21 — main bearing корінний підшипник; 22 — journal корінна шийка (вала)

The small end of the connecting rod is rotatably con­nected to the piston by the piston pin. The big end of the connecting rod is also rotatably connected with the crank­shaft. The flywheel is located on the rear end of the crank­shaft. It is equipped with a toothed rim for meshing with the starter pinion. Piston with piston pin, connecting rod and crankshaft with flywheel are called crank-drive as­sembly.

Inlet of the fuel-air mixture into the cylinder and out­let of the burned gases are controlled by valves. The valves are actuated by the camshaft generally supported in the crankcase. Valves, camshaft and camshaft drive are forming the control mechanism of the engine.

The crankcase bottom is closed by the oil pan holding the oil required for lubrication. The oil pan is connected to the crankcase.

The liquid fuel is mixed with air and vaporized in the carburettor. This fuel-air mixture enters cylinder and com­bustion chamber. Inside the combustion chamber, the fuel-air mixture is ignited and burned by a spark jumping at the electrodes of a spark plug.

The generator is located at and driven by the engine. When the engine is running at sufficient speed, the gene­rator supplies the ignition current and charges the sto­rage battery.

The starting motor is a small electric motor. When it is actuated, a driving pinion is shifted and meshes with the toothed rim of the flywheel. Thus the crank-drive as­sembly begins cranking (working).

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