Design News for Mechanical and Design Engineers

In the early days of industrialization there was a marked lack of safety equipment. The cost of unguarded cutting machines, open belt and chain drives, and the struggle to keep unreliable machines running was no doubt apparent in the number of accidents that occurred. Today the situation has changed, and the supply of safety equipment for machines is a thriving industry in itself.

Design News: Adding safety devices to machines and processes often slows them down and increases complexity. How do you resolve the conflict between providing an adequate level of safety and efficient production?

BAUR: With regard to the installation of safety devices, close cooperation with machine builders has to take place, right at the early design stages of a machine. Only then can solutions be found which do not impair the performance of machines and processes. The inclusion of intelligent safety technology in design is one of the primary methods used in countering undesirable sequences in machine operation. One example of this is the muting system which differentiates between the passage of production materials and parts of the human body through the protection barrier.

Q: We often speak of safety for man and machine. Can we lump them together into one?

A: No! Although there are interrelating aspects, we make a strong differentiation between the two. Safety engineering for machines encompasses the technical realization of the machine, enabling the monitoring of machine functions. This activity prevents machine downtimes, minimizes disturbances in the production process and, above all, keeps product quality up to specification. On the other hand, when referred to persons, safety engineering specifically covers the protection of operators and others from any hazards that may be present. The protection of life and limb is quite different from the protection of the machines themselves.

Q: Is the market for safety devices mainly driven by standards?

A: Manufacturers, including those producing safety devices, have responsibility for the quality of their own products. This compels them to take appropriate measures to ensure product quality. Of course, current, and often forthcoming standards, must be taken into consideration at the early design stages. Generally, you could say that standards tend to increase development effort and lengthen development times.

Q: Do intelligent sensors and actuators play a significant role or does the intelligence reside solely in the machine controller?

A: Within the field of safety technology, intelligent sensors are becoming increasingly important. This is primarily because the demand throughout industry for flexibility in production is growing stronger. Consequently, production engineers expect to be able to make changes to production processes without a lot of complicated manual reconfiguration work on the safety equipment. Intelligent safety devices provide versatile adaptation to production processes without any increase in the risk to personnel. At wenglor we have gone even further than the standards require and have included many additional functions such as muting, blanking, and cycling modes.

Q: How do you see the trends for the future?

A: For our part at wenglor we intend to continue to develop new products and improve existing ranges, exploiting the latest advances in technology. Our customers expect this and we have to remain competitive. We currently have a new Category 4 safety light barrier in development—just to mention one example. More generally though, I expect the main theme in the future will be increasing sensor versatility with equipment having to become smarter to fulfill this requirement.