Rotating energy supply system in rotatable wind tunnel balance in automotive industry

Profile

• What was needed: rotating energy supply with reverse bend radius (RBR), E4/4 system
• Requirements: independent feeding of power cables, measuring and control cables and fluid cables, taking electromagnetic compatibility (EMC) criteria into account, a compact and cost-effective system that can be implemented with short installation times
• Industry: automotive industry
• Success for the customer: the rotating energy supply systems used can implement rotation angles of up to 540° in the smallest installation space, the design is so flexible that around 140 assembly hours could be saved compared to previous projects

Cut-out with the rotating energy supplies. In this area, the separation of the individual chains can be seen very well.

Problem

In the area of a wind tunnel balance, the electrical and fluidic connection had to be solved in a user-friendly way, taking into account the required rotation angle +- 180°. Independent feeding of power cables, measuring and control cables and fluid cables had to be ensured in compliance with electromagnetic compatibility criteria. Another requirement for the cable guidance for the wind tunnel balance was to implement a system that was as compact and cost-effective as possible with only a short installation time. The mechanical trough structure should be very flexible with regard to the connection points on the existing machine frame in order to be able to easily compensate for positional inaccuracies and height differences. Another of Horiba's objectives was to use the solution for another electromagnetic compatibility test rig with a similar basic design and a rotation angle of +- 197.5°. The application travels at a maximum of 2°/s.

Solution

In close co-operation with the customer, a solution was found to implement both applications, i.e. the cable guidance for the wind tunnel balance and the EMC test rig, with one basic mechanical system. Today, the cables are guided in  three energy chains with reverse bend radius (RBR) of E4/4 (Series 5050), which are used in different lengths and with different interior separations. The rotating energy supply systems travel in guide troughs and can now achieve a rotation angle of up to 540° in one plane in a minimum of installation space. The basic mechanical structure was designed so flexibly in terms of adjustment options in a collaborative effort that about 140 assembly hours were saved compared to previous projects. To achieve the compact design, chainflex cables were also used for the power cables.

Schematic diagram of a wind tunnel balance

Section of the wind tunnel balance in the construction phase. The outer trough is anchored to the ground via levelling elements. The inner trough is rotatable and connected to the base frame via flexible adjustment elements.

Section of the cable inlet of the power cables.