Body structure
According to the force of the body, it can be divided into two types: bearing body and non-bearing body.
Load-bearing body
The load-bearing body has no frame. The body serves as the mounting base for the engine and chassis assembly. The body also functions as the frame and bears all the loads.
The structure in which the chassis components (engine, suspension, etc.) are directly mounted on the vehicle body is mainly composed of thin plates. In order to alleviate the stress on the mounting parts of the chassis and ensure the rigidity of the vehicle body, some vehicles will be equipped with a sub-frame. One end of the chassis is mounted on the sub-frame, and it is also mounted on the vehicle body.
advantage
1. Light weight, good overall bending and torsional stiffness;
2. The center of gravity is low, the floor of the cabin is low, and the height of the vehicle is small;
3. It is mainly for thin plate processing, and spot welding can be used, which is easy for mass production.
Disadvantage
1. Noise and vibration from the road and engine are easily transmitted to the vehicle body;
2. Because the entire body is used to ensure stiffness, it is difficult to modify.
The following figure is a semi-finished body of a load-bearing body. You can see that the shell, roof and floor of the body and the so-called A, B, and C columns are all connected together. In the stamping phase, the steel sheet is first stamped into different shapes and then welded into a complete body. These parts can be roughly divided into two types according to their functions: body covers and structural parts.
The so-called cover is a component that covers the surface of the body. Basically, the parts we see from the outside of the car are covered, such as doors, roofs, fenders, etc. They usually play a role of beauty and wind and rain. Generally, it is stamped from a steel plate with a thickness of not more than 1 mm. The thickness of a car's steel plate usually refers to these parts. In fact, the impact of these parts on the strength of the vehicle body is very limited, so we can no longer judge the collision safety of a car from the thickness of the body cover. Of course, thicker steels are better at resisting mild scratches.
