In order to make the appropriate shape of metal, etc., according to the application, a method called cutting is used, in which metal is shaved with a special tool. Japan's cutting technology is highly regarded worldwide and has supported manufacturing for many years.
In cutting, if an abnormality occurs in the tool, accurate machining cannot be performed, so careful attention must always be paid to wear and tear. Experienced technicians have been able to grasp the machining and the condition of the tool by sensing all kinds of information such as vibration and sound during machining, the appearance of chips, and the condition of the machined surface with all five senses, and have always maintained an appropriate cutting condition to achieve high-quality machining.
"It has been said that cutting is a world of 'intuition, experience and courage.' Of course, these factors are important in the field, but we cannot keep records or compare products," said Daisuke Murakami, Advanced Materials Laboratory, Sumitomo Electric Industries. To solve this problem, Sumitomo Electric Industries developed Sensing Tool by using STREAL.
"At first, I was asked to make a tool that screams," said Murakami. In other words, it was important to be able to detect the abnormality of the tool immediately, and first of all, they examined the sensing using the acceleration sensor in the smartphone. However, it was difficult to obtain and analyze data for monitoring the machining conditions, so they were looking for other means.
Murakami first learned about STREAL in 2018 when he visited the laboratory of Katsuhiko Sakai, an associate professor (professor currently) at Shizuoka University, with whom he was collaborating. "STREAL was attached to the tool that a student brought," said Murakami. After hearing the explanation from Associate Professor Sakai, Murakami thought, "This is it!" and immediately inquired with Glosel (the company name at that time was Renesas Easton).
Yusuke Koike, who is active in Murakami's team, recalled, "Glosel was also looking for a market that could capitalize on STREAL's strengths. As we had a series of meetings, we got along well and decided to work together."
The development team aimed to accurately detect changes in machining conditions by measuring the strain of the holder near the machining point. This requires reading minute changes in the holder rigid and difficult-to-deform. This is because reducing the rigidity of the tool and making it easy to deform leads to a reduction in the quality of cutting.
Therefore, Murakami and his colleagues used STREAL, which can measure minute strains, to detect changes during machining without reducing rigidity as much as possible. "Conventional strain gauges were difficult to mount on tool holders due to wiring and other problems. On the other hand, STREAL was able to incorporate all the parts into the body and was able to clear the interference with the workpiece," said Koike.
Sensing Tool created by this ingenuity can detect a force that cannot be detected visually as much as by lightly pressing a hard holder with a finger. The data is then transmitted wirelessly to a PC placed outside the machining tool, and the machining conditions can be viewed in real time.
"We've heard a lot of requests from people who want to see what's going on during cutting," said Murakami. The use of Sensing Tool to meet these requests has already started, and the response has been great.
If the state of machining can be visualized, it is expected to optimize machining using accumulated data, reduce production losses, improve operational efficiency, and improve quality. STREAL continues to support them leveraging the characteristics of compact size, high accuracy, and low power consumption.
