Torsion-resistant energy chain in compact X-ray robot in radiotherapy

A large number of cables for medical equipment must be installed in the radiation-protected treatment room. The limited ceiling height and the compact panelling of the patient positioning system make cable routing difficult. The main reason for the very large number of cables is that no electronic components may be used in the radiation room. These could be damaged by radiation. The connections of all sensors, motors and electrical components must be routed over a long distance to a radiation-free room. For this purpose, it was necessary to realise the most efficient cable routing possible, as the installation space in the next radiation-free area can be very limited. Due to the complex movements performed by the patient positioning system, cable guides for torsional stress were also necessary. The most difficult part was to find electromagnetic compatibility-capable cables with a very small bend radius and torsional strength. These are necessary in order to fulfil the electromagnetic compatibility limits for medical devices despite the long cable.

Limited space with maximum movement and a large amount of cable present an almost unsolvable problem for cable routing. In the exacure system, this challenge was overcome by using two of our systems and a variety of cables. An E2/000 plastic-energy chain from the 3400 series is installed in the linear axis. This allowed the installation height to be reduced without restricting functionality.
On the robot, the patient couch with imaging unit must be rotatable by up to ± 200 degrees and tiltable by ± 10 degrees. The cables must be routed along the robot under the panelling and be guided along with the patient couch's rotational movements. The risks of torsion in the cable harnesses and tearing of the cable harness must be taken into account. These requirements were met with a triflex® energy chain. Previous solutions were built up towards the front in the direction of the therapy beam. The new optimised arrangement builds up to the side and allows more cable, e.g. for X-ray technology, to be brought close to the patient without reducing the treatment volume. The triflex® chain also enables optimum integration with drastically reduced installation and commissioning time. In addition, the complete package including all connectors was purchased pre-assembled as a readychain® solution.