Experience Leads to Success

MOHR (Germany) - This plastics and metal working company uses Stäubli 6-axis-robots in fully automated cells for metal gearshaft coating and printed circuit boards, as well as in fully automated assembly cells for heated windshield wiper nozzles for the automotive industry. Six Stäubli robots - models RX130, RX90, RX90 L and RX60 - are used to tend the Demag Ergotech and Arburg injection molding machines. Another three Stäubli RX industrial robots are used for additional assembly applications.

Eleven years ago, a small 6-axis-robot marked the beginning of the first fully automated cell at MOHR, integrating injection molding, assembly and 100% quality control. The most important requirement was the ability to deliver flawless products, eliminating increased costs due to defective parts.

From this first robotic experience, the former production supervisor Paul BUND and his team tried to solve more difficult automation problems, such as a manufacturing cell for the indicator control switch of the Audi A4 / A8. For this application, a Stäubli RX 130 was chosen for loading and unloading the injection-molding machine. Equipped with a multiple revolving gripper, the robot picks two metal inserts from a vibrating conveyor as well as two prefabricated printed circuit boards from a pallet. After the injection operation has ended, the finished coated parts are picked from the tool of the injection molding machine; the inserts and printed circuit boards to be extruded are inserted into the tool with an accuracy of less than 5/100 mm. The finished parts are then fed to a stamping and high-voltage testing device. Afterwards they pass an optical control to detect any mold faults. Depending on the inspection results, the finished parts are finally palletized or fed to a reject conveyor. The robot's high speed fulfilled the cycle time requirement of less than 40 seconds.

The MOHR engineers tried to handle even smaller parts, which had to be positioned even more precisely. The specificity of the new manufacturing cell is a 2x2 tool mounted on a turntable, consisting of two pairs of cavities which extrude the sensor connectors for BMW motor control with polyphenylene at a temperature of 136°C.  A Stäubli RX90 L tends both pairs of cavities, situated inside and outside the tool.

The advantages of the Stäubli RX industrial robots lie within the highly precise positioning enabling a fast and exact pick and place of the extruded parts. Furthermore, the Stäubli RX industrial robots are powered by a controller with the powerful V+ programming language which enables the control of the robot from machine tending to production control.

STÄUBLI is a 100+ year old, 2,400-employee Company with annual revenues of over 700 million Swiss Francs, headquartered in Switzerland. The STÄUBLI Group commitment to customer satisfaction is proven by worldwide office locations offering a 'first class' level of services such as training and maintenance.

In its production facility located in the heart of the French Alps a few miles south of Geneva (Switzerland), STÄUBLI's Robotics Division invests 12 % of its revenues in Research and Development. An innovation and quality strategy has led STÄUBLI to be awarded ISO 9001 for its three divisions: textile, connectors and robotics.

For additional information, please contact
Marketing Manager
Stäubli Corporation - Robotics Division
201 Parkway West
Duncan, SC 29334
USA
Tel. 864-433-1980
Fax. 864-486-5497
[email protected]