Car Beauty Knowledge -- Overall Structure of a Car
I have worked in the local car repair industry for many years and now I would like to share my experience with everyone.
Cars are usually composed of four parts: the body, engine, electrical equipment, and chassis.
1. Body
The body is where the driver works, as well as the place for carrying passengers and goods. It should provide the driver with convenient operating conditions, as well as provide passengers with a comfortable and safe environment or ensure that the goods remain undamaged. A typical truck body includes components such as front sheet metal parts, cab, and cargo compartment; a typical three-box sedan consists of an engine compartment, trunk, and passenger compartment.
2. Engine
The function of the engine is to burn fuel and output power. Most cars use reciprocating internal combustion engines. They are generally composed of several parts including the engine block, crankshaft connecting rod mechanism, valve train, supply system, cooling system, lubrication system, ignition system (used by gasoline engines), starting system, etc.
3. Electrical Equipment
Electrical equipment is composed of power units, engine starting systems and ignition systems, automobile lighting and signal devices, etc. In addition, modern cars are increasingly equipped with various electronic devices, such as microprocessors, microcomputers, and various artificial intelligence devices, significantly improving the performance of automobiles!
4. Chassis
The chassis receives power from the engine to make the car move and ensures that the car travels normally according to the driver's operation. The chassis mainly consists of the following parts:
1) Transmission System: Transmits the engine's power to the drive wheels. The transmission system includes components such as the clutch, gearbox, drive shaft, and drive axle.
2) Running Gear: Connects all assemblies and components into a single unit and supports the entire vehicle to ensure normal travel. The running gear includes components such as the frame, front axle (non-drive axle), drive axle housing, wheels (steering wheels and drive wheels), suspension (front suspension and rear suspension), etc.
3) Steering System: Ensures that the car can travel in the direction chosen by the driver, consisting of a steering wheel-equipped steering gear and steering linkage.
4) Braking System: Slows down or stops the car and ensures that the car remains reliably parked after the driver leaves. Each car's braking system includes several independent braking systems, each consisting of an energy supply device, control device, transmission device, and brake.
Maximum Speed of the Car
Refers to the maximum speed a car can reach on a level, good asphalt or concrete road surface under windless conditions. The maximum speed listed in the car's manual is measured over the final 500 meters of a 1.6-kilometer test section at the highest gear and full throttle. The maximum speeds of current highway sedans range from 120 kilometers per hour to 280 kilometers per hour. There are also specially designed racing cars and sports cars whose top speeds can approach or even exceed 400 kilometers per hour (some pure speed racing cars are equipped with jet engines, reaching close to 1000 kilometers per hour, requiring drag parachutes for braking!).
Acceleration Time (Acceleration Capability)
Refers to the ability of a car to increase its speed while driving, usually expressed in terms of acceleration time and distance. Acceleration capability includes two aspects: stationary start-up acceleration and overtaking acceleration. Stationary start-up acceleration refers to the time it takes for a car to continuously shift gears from a stationary state to the highest gear and accelerate to a certain distance or speed. There are two ways to express this: the number of seconds required to accelerate from a speed of 0 to one kilometer (or 400 meters, or 1/4 mile); the number of seconds required to accelerate from a speed of 0 to 50 kilometers per hour (80 kilometers per hour, 100 kilometers per hour, 50 miles per hour). Of course, the shorter the time, the better. For compact cars, the acceleration from 0 to 100 kilometers per hour generally exceeds 10 seconds; for mid-to-high-end cars, it is usually around 10 seconds or less; some racing cars and sports cars have an acceleration time from 0 to 100 kilometers per hour that can be less than four seconds. Overtaking acceleration refers to the time it takes to fully accelerate from the lowest stable speed of the highest gear or sub-highest gear to a certain high speed. When overtaking on the road, traveling alongside the overtaken vehicle for a period of time is most prone to accidents, so overtaking acceleration is very important. The quality of overtaking acceleration has a lot to do with the torque characteristics of the engine, and it is best for the maximum torque segment of the engine to decrease slightly smoothly.
Overall Performance of the Car
Besides the highest speed, acceleration time, minimum turning diameter, fuel consumption, and wind resistance coefficient, the main performance parameters of a car also include indicators representing its passability, such as maximum climbing gradient, minimum ground clearance, approach angle, departure angle, longitudinal passing angle, etc.
Ground Clearance of the Car
Refers to the distance between the ground and the rigid objects on the bottom of the vehicle. The minimum ground clearance in the car specification table refers to the distance between the ground (flat) and the lowest point of the rigid objects on the bottom of the vehicle. Determining the ground clearance involves factors like fuel tank height and the lowest contour line of the engine.
Maximum Climbing Gradient of the Car
Refers to the maximum climbing gradient a car can achieve while driving in first gear on a good road surface. For off-road vehicles, climbing ability is a quite important indicator because they often need to drive on bad roads or even no roads. Generally, they are required to climb slopes of no less than 60% or 30 degrees; cargo trucks are required to have a climbing ability of about 30%; sedans have higher top speeds and frequently drive on better roads, so their climbing ability is not emphasized. Generally, their climbing ability is around 20%.
Minimum Turning Diameter of the Car
Refers to the diameter of the trajectory circle of the outermost end of the outer wheel when the steering wheel is turned to the extreme position on a wide and flat area. Because left turns and right turns are slightly different, the average value is taken after performing left turns three times. The smaller this value, the better the maneuverability and flexibility of the vehicle. This is one of the performance indicators where small vehicles can outshine large luxury cars.
Fuel Consumption (Fuel Economy)
"Fuel consumption per hundred kilometers" (fuel economy indicators in European and American countries are "liters of fuel per mile") refers to the number of liters of fuel consumed while driving 100 kilometers. This indicator is divided into the following two types. One is the equal-speed fuel consumption per hundred kilometers: the national standard stipulates the fuel consumption while driving one hundred kilometers at an equal speed in the highest gear under rated load on a level and good road surface; the other is the cycle condition fuel consumption per hundred kilometers: the fuel consumption while driving one hundred kilometers according to the combination of various specified typical driving conditions. Manufacturers mostly refer to the equal-speed fuel consumption per hundred kilometers at economic speed when promoting the fuel consumption of their car products (this speed can be calculated from the engine's external characteristic curve at the lowest fuel consumption point). The cycle condition fuel consumption per hundred kilometers is closer to the actual operation of the car, and the difference between the two is quite obvious. Therefore, if the manufacturer claims that the car consumes only 6.5L per hundred kilometers, but your actual result is tenL, you must understand what's going on.
This article was collected online by the Car Beauty Talent Recruitment Network. Please visit China Auto Beauty Talent Network for car beauty talents.
Source: http://www.qcmrrc.com/