Omron improves safety and quality at DELPHI

The DELPHI factory at Flers near Douai/France, a modern industrial site inaugurated in 1996, is devoted to the manufacture of automotive air conditioning compressors for numerous manufacturers such as Opel, Renault, Nissan, GM, FIAT, BMW, Isuzu, Saab and even Ferrari. The factory produces more than 2 million compressors each year.

Omron has equipped the site with safety light curtains in order to protect operators’ hands in accordance with the obligations of European Directive 98/37/EC. In all, about fifty light curtains are installed on the machines, conveyors and various work bays. If a hand or object gets in the way, the photoelectric sensors of the light curtain cut the power supply to the work bay.

Ease of implementation

Safety sensor solution for safe applications DELPHI chose Omron light curtains for their ease of implementation; according to Mr. Witczak, Engineering Manager, “the compact nature of the Omron light curtains made it easier for us to install them on the existing equipment; another advantage is the rapid connection system with safety relays which simplify the wiring and eliminate the risk of errors, resulting in easier and quicker implementation.”

Omron is also working with DELPHI to improve quality. The factory produces about forty compressor models; the differences are mainly on the outside of the casings so as to comply with the mounting constraints of the various vehicles. To achieve zero defects it is essential that at the crucial stages of assembly, each compressor conforms to the model being manufactured.

Omron vision system detects the slightest error

Since August 2001, 3 cameras and 3 associated controllers have been installed. “Each part is photographed and the image is processed using a software package which then outputs either a ‘Good’ result or a ‘No Good’ result; if there is a problem, the work bay is automatically shut down and the part is examined: it’s the same principle as the Poka Yoke* method”, explains Mr. Witczak. The Omron vision system makes it possible to detect the slightest error by continuously comparing production with the model in the controller’s memory. This system replaces manual monitoring using measuring gauges, which was not entirely satisfactory.

Pursuit of excellence

“Our main concern is having as low a client return as possible. Our pursuit of excellence has led us to achieve a current client return of less than 20 PPM (parts per million), taking the last three years into account, which is in itself a remarkable result. The installation of the Omron equipment will enable us to dip further under this threshold”, adds Mr. Witczak. “We are also working with Omron for a variety of other reasons: our factory is equipped with both European and Japanese software which have reversed sequential logic standards! Omron easily adapts to suit both methods without the need for additional interfacing software and also has a very extensive range of products which encompasses almost all our needs.

Last but not least Omron accompanies its clients every step of the way, whether through After-Sales, product follow-up or commercial assistance and that is something which we greatly appreciate.”