Although we may be transitioning towards electric vehicles and alternative fuels, conventional cars still rely heavily on internal combustion engines to power their wheels. A combination of thousands of mechanical and electronic parts works together seamlessly to power your car.
Fuel combustion in a cylinder creates energy which drives pistons up and down, connected to a crankshaft which converts linear motion into rotational energy that propels your car wheels.
Cylinder
Car engines serve a vital purpose in powering our cars: turning fuel with spark ignition into mini, controlled explosions that power your wheels and turn linear motion into rotational movement. Cylinders house these explosions that help turn linear into rotational movement.
A cylinder is a three-dimensional shape composed of two flat ends connected by circular surfaces to form two flat surfaces resembling circles, joined together with an arched surface that resembles a tube. Cylinders in engine engines feature pistons which move up and down within their combustion chamber; when reaching its lowest stroke point, spark plugs ignite gas/air mixtures that burn and produce high pressure gases that push back up through its stroke; these high pressure gases powering your crankshaft and driving wheels.
Your car engine contains multiple cylinders located within its cylinder head. Each of these cylinders are protected from friction with its walls by an oil droplet ring enclosing them; their size and shape have an impactful influence on performance – engine configuration with more cylinders can generally produce more power, but that extra power requires extra fuel which lowers gas mileage; some technologies such as turbocharging or supercharging boost power without increasing the number of cylinders required to reach full potential.
Crankshaft
The pistons move up and down within their cylinder, producing mechanical energy which the crankshaft converts to rotational energy to drive your car’s wheels. This massive and extremely heavy piece of equipment sits at the bottom of your engine block with main bearing journals and crank pin bearings, connecting rods offset in zig-zag patterns from its axis and connected to piston pins (big ends of pistons).
Connecting rods and pistons are rapidly accelerated from rest to very high velocity twice during each crankshaft revolution, creating significant forces on connecting rod beams and small ends, piston pin and ring packages, crankshaft journals and bearings, as well as counterweights cast into crankshaft journals to counterbalance these forces.
The crankshaft operates the camshaft to open and close cylinder valves during each combustion cycle, using a timing sprocket on its front to coordinate camshaft rotation with piston up-and-down movement. As it spins at engine speeds of several thousand revolutions per minute, its delicate balance must remain uncompromised.
Valve Train
Car engines use explosive combustion to convert chemical energy into mechanical motion that moves your wheels. But for that to occur, the piston needs to be pushed up and down within its cylinder by expanding gases (see first image), which requires a valve mechanism which opens and closes at just the right moment ( see second image).
Valve Train systems regulate the opening and closing of valves by controlling their timing and lift profiles with care. At its heart lies the camshaft, which sits either in the head or block of an engine and contains series of carefully designed lobes which control timing and lift profiles for all of the valves in its care.
These lobes are activated by the crankshaft through rubber or metallic timing belts, chains or gears; their camshaft then rotates at approximately half speed of the crankshaft, with their lobes then pushing on pushrods or rocker arms which push up or down on valves in response.
Flat tappets with ball ends designed to accommodate misalignments are shown above; their primary task is to transfer force from a cam lobe onto a rocker arm that pivots on an axle stud in its middle and finally to push rod that contacts valve stem. As piston descends, force from rocker arm pushes on push rod contacts valve stem, opening or closing as needed depending on piston motion.
