automobileOn-board harnessIt is the backbone of automobile circuit. Without wiring harness, there is no car circuit. With the increase of people's requirements for safety, comfort, economy and emissions, the car harness becomes more and more complex, but the space of the car harness is getting smaller and smaller. Therefore, how to improve the overall performance design of automobile harnesses has become the focus of attention. Automobile harness manufacturers are no longer simply engaged in the design and manufacture of harnesses, and it has become a trend to carry out preliminary development work with automobile manufacturers.

On-board harness and fixing design of the whole vehicle:

（1） Harness packaging design: the harness is outsourced to wear, flame retardant, anti-corrosion, interference prevention, noise reduction and beautification. Generally, according to the working environment and space, the following dressings are formulated

Plan. The engine harness has a harsh working environment, so it is completely wrapped by bellows, which has high flame retardance, water resistance and high mechanical strength. Working environment of front cabin

It is also relatively poor. Most branches are also wrapped with flame retardant corrugated pipes, while some branches are wrapped with PVC pipes. The working space of the instrument line is small and the environment is relatively good. It can be wrapped or taped

Wrap. The working space of the door line and roof line is small, which can be completely wrapped with adhesive tape, and some branches can be wrapped with industrial plastic cloth; The thinner roof line can be directly adhered to the body with sponge tape. Since there are many contact parts between the chassis wire and the body, wrap them with corrugated pipes to prevent harness abrasion.

（2） Performance analysis of vehicle harness using different raw materials

1. The bellows usually occupies 60% or more of the bundle dressing. It is mainly characterized by good wear resistance, and high temperature resistance, flame resistance and heat resistance in high temperature zone. The temperature resistance of bellows is between - 40 and 150 ° C. Its materials are usually divided into PP and PA2. PA material is superior to PP material in flame retardance and wear resistance;

2. The tape plays a binding, wear-resisting, insulating, flame retardant, noise reduction, marking and other functions in the bundle, generally accounting for about 30% of the wrapping material. The harness tape is generally divided into three types: PVC tape, air flow mesh tape and cloth base tape. PVC tape has good abrasion resistance and flame retardancy; The temperature resistance is about 80 ° C, the noise reduction effect is poor, and the price is cheap. The material of flannel belt and cloth base belt is PET. The binding and noise reduction effect of flannelette tape is the best, and the temperature resistance is about 105 ° C; The cloth base tape has the best abrasion resistance, and the temperature resistance is about 150 ° C. The common disadvantage of flannel tape and cloth base tape is that it is not flame retardant and expensive.

3.3 Fixing design of wire harness The central electrical box is usually fixed with steel strips, bolts, etc., or directly installed on the vehicle body by the fixed structure designed by the electrical box itself. Generally, each harness is fixed in the main body hole through plastic cable ties, hooks, etc. The main body holes are mostly round or elliptical holes with diameters of 5mm, 6mm and 7mm. The sheath between the harnesses is usually fixed and installed on the vehicle body by the sheath bracket. The body lines of Sea Lion, MPV and other larger models are long and thick, and are usually fixed on the body to reduce vibration and noise.