Control method and arrangement of trunk and branch of automobile wiring harness

Because the vehicle has more electrical functions, the main part of the wiring harness contains a large number of loops, the wire diameter is large, and some main trunk areas are affected by the layout of surrounding parts. Corrugated tubes, insulating tape or other protective materials must be wrapped to protect the main trunk area during assembly. Difficult. The too large and rigid trunk of the wire harness also makes it difficult to control the direction of the wire harness, the assembly process is laborious, and it is difficult to ensure the quality of the assembly. In view of the above problems, this article mainly introduces the design considerations for the optimization of the trunk branch of the lower wiring harness.

(1) the size and hardness of the trunk

If the diameter of the wiring harness is too large, sufficient space must be reserved when bending at a certain angle. Generally, the bending radius of the wiring harness should be greater than twice the diameter of the wiring harness to avoid damage to the wiring harness and the connector due to the small bending space [2].

In the process of three-dimensional wiring harness layout, the uncontrollability of the wiring harness should be fully considered, and the reliability of the layout should be evaluated in combination with the actual vehicle assembly experience. The bending of the wire harness should avoid sharp edges of sheet metal and edges of peripheral parts as much as possible to prevent damage to the wire harness.

(2) Control of reserved length harness

The reserved length needs to ensure the docking of the connector, while avoiding abnormal noise and interference. It needs to be analyzed by data analysis of previous models and verified by actual cars to obtain a reasonable length requirement. At the same time, it is possible to avoid damage to the wiring harness by increasing the external cut-resistant wrapping of the wiring harness, and adding cutting-proof adhesive tape to the surrounding sharp parts, and to reduce abnormal noise by wrapping the sponge.

(3) Harness via

The wire harness needs to pass through a sheet metal hole, and the diameter of the sheet metal hole is at least 1.3 times the connector size. This is for the efficiency of wiring harness assembly, and also to ensure the integrity of the parts when the wiring harness passes through the hole.

This requirement also applies when the wiring harness passes through the closed cavity. Some wiring harness arrangements need to pass through the inner and outer panels of the tailgate, the cavity between the inner and outer panels of the side panels, etc. In the direction of the wire harness passing path, the diameter of the cavity space cross-section is greater than 1.3 times the connector.

In addition, it is also required that the interior of the cavity through which the wire harness passes is smooth and unobstructed, and there must be no obstructions such as bolts and body reinforcement plate edges in the cavity. Such as
This: one is to ensure that the harness does not interfere with sharp objects; the other is to prevent the harness from stagnation when it is difficult to control the direction of the harness through the closed cavity.

(4) The wiring harness affects the gap difference

When designing, you can press out the wiring harness assembly path to the outside of the fixed sheet metal surface of the harness. At the same time, you can use a flat card buckle to make the wiring fit the sheet metal more and increase the gap between the wiring harness and the trim.