“Historic” MOTOMAN robot in operation at wheelchair specialist MEYRA GmbH
11. October 2018
A wheelchair incorporates more high-tech than one might expect: for each wheelchair about twelve metres of tubing and other bar material must be cut, bent, drilled, welded, coated and assembled. MEYRA GmbH, founded more than 80 years ago and based in Kalldorf, is one of the best known and most successful wheelchair manufacturers, and also a supplier of rehabilitation aids. The global enterprise produces top quality wheelchairs and rehab equipment on a floor space of over 30,000 m². With individual solutions according to the slogan “We move people”, MEYRA GmbH offers mobility and independence to people with handicaps. The wheelchair specialist’s spirit of innovation is reflected not only in the ongoing development of products and services, but also in its choice of production machines. MEYRA GmbH was one of the first companies to employ a welding robot in production. It is precisely this robot that has now been welding for over 30 years – reliably and in premium quality.
Robot as a production driver
The demand for high-quality wheelchairs rose so rapidly in the 1980s that MEYRA GmbH was obliged to move to larger premises, and production at the Kalldorf site started in 1984. Tell Putsch, works manager at MEYRA GmbH looks back: “Our production figures continued to increase after the move to Kalldorf. Within only a short time the newly occupied factory space and personnel were working to capacity. Our company had to seek new, innovative techniques to enable it to fulfil all orders in the accustomed high quality and to the agreed deadline. The solution was found at robot specialist Yaskawa, which had just produced its first welding robot. “The then brand new V12B-RX significantly increased the production capacity of MEYRA GmbH and made the forerunner in wheelchair technology a pioneer of robot welding technology.
V12B-RX welding robot
The six-axis robot with a payload of 12 kg and a repeatability of 0.2 mm immediately set a benchmark in terms of precision and output. Already in the 1980s, the robot operator-friendliness achieved by Yaskawa was such that after a brief introduction by a Yaskawa robot professional the employees of MEYRA GmbH were able to independently program the welding robot. The first robot operator is already in retirement, but the robot itself has not yet even considered ending its career.
Gerd Hunger, pre-production manager and long-time programmer/operator of the Yaskawa welding robot, describes his work with the V12B-RX: “Earlier, the welding robot was operated continuously in two shifts, but over the past eight years we have used the V12B-RX less frequently. Nowadays the trend in production is towards individual fabrication. This calls for more personnel deployment and less robot support. Nevertheless, the V12B-RX is still used on a regular basis, when larger quantities of the same component have to be welded, e.g. wheelchair frames or small parts. Even after 30 years, the quality of the welding seams has not diminished, and with the exception of a few wearing parts, nothing on the robot needs to be repaired.”
Retrofit as a cost-effective alternative to new acquisition
It is no coincidence that after more than 30 years the V12B-RX welding robot still delivers high-quality welding seams. The long life of the products has always been an integral part of Yaskawa’s corporate philosophy. With a focus on sustainability and economic efficiency, the Japanese robot specialist systematic has developed retrofit programmes that breathe new life into the old robots.
An increasing awareness for costs and resources has resulted in extended use of industrial production plants. Entrepreneurial risk increases with the likelihood of a mechanical defect. In the case of a malfunction, production may be interrupted for several days. The solution is often to replace old robots with new ones. As an attractive alternative to new acquisition, Yaskawa offers systematic retrofit programmes for time-worn robots. The robots undergo an overhaul at regular intervals, or are replaced by an already overhauled robot. On average about 60% of the wearing parts of a robot are completely renewed in the course of a retrofit.
On account of the permanently high level of motion stress to which they are subjected, the manipulators are the focus of most retrofit measures. They are thoroughly cleaned, repainted, put through their paces in a 24-hour test run and recalibrated. A fixed price that is determined according to the robot’s payload offers maximum investment security. In addition, Yaskawa increases the warranty period on replaced components by one year.