KOYO ELECTRONICS INDUSTRIES first learned about cobots in 2017. “A proposal was made by Inaba Denki Sangyo Co., Ltd., an official distributor of Universal Robots. As the robot is lightweight and space-saving, we didn’t need to make a major layout change and considered implementation,” Says Mr. Nakatani. The UR cobot has safety functions such as protective stops. The fact that it could be installed without a safety fence was a decisive factor in implementation.

UR3 was introduced in the touch panel quality inspection process. When the UR3 touches the touch panel with a stylus, “OK” is displayed if there is no quality error, and the green signal of a signal tower lights up. When an abnormality is detected, “NG” is displayed on the display, the red signal tower lights up, and the buzzer sounds continuously. As a result, the person in charge immediately notices the abnormality and can respond.

“We conducted risk assessments in accordance with our company’s safety standards and worked on ensuring the safety of workers. At the beginning of implementation, we made certain adjustments such as speed reduction as the staff was afraid of moving the robot at high speeds,” says Mr. Atsushi Fujita, Chief in the Production Technology Department “As the cobot works with higher accuracy and stability than humans, the quality of the work improved as a result.”

It took approximately three months from the delivery of the robot, to the system design, setup, testing, solving various problems, and operation on the line. The hardest part was connecting the UR robot to external devices such as a PLC and a PC. “It took about two weeks of trial and error, but we finally could build our own system that does not depend on any external resources, such as SIers,” Mr. Fujita said. In addition, the part that allows the cobot to hold the jig was improved. At first, it did not work properly because the jig was heavy, but they finally managed to make the jig easier to hold through repeated fine-tuned adjustments.

Ms.Yuki Oshiba, the person in charge of the inspection process, explains. “Humans tend to make mistakes when working with a touch-panel system, and we are happy to have cobots to do this work accurately and complete the task properly. Since our job was only to press the ON/OFF button, we can now do other duties while the robot is working, making the system very productive. When there is an abnormal shut-down, an alert is issued, and the person in charge of production technology will come by, so we can rest assured that no interruptions in production will happen."

Furthermore, as external resources were not used in the implementation of UR, investment in safety measures was minimal. Koyo Electronics was a surprised to see that investment capital could be recovered in just one year and is now considering UR cobots in other processes. “For example, in the substrate processing process, we are examining whether it can be used for sending the substrate that has completed a process to the next process, etc. By implementing the UR cobot, the number of post-inspection process personnel was reduced from two to one,” says Mr. Nakatani. “Not only has our company been able to improve productivity by allocating resources to another production process, but the experience from implementing this robot has built confidence and high hopes for future development.”