Components of R&D are critical to the industry’s innovation and ability to meet customers’ specific needs. Take Chicago-based Winzeler Gear, for example. Founded in 1940 as the Winzeler Manufacturing & Tool Company by Harold Winzeler, the company has made a name for itself in the precision molded plastic gearing industry through its aggressive and creative approach to R&D.
When Harold first pursued manufacturing plastic gears, he was thinking ahead of his time.
“Plastic gearing is a relatively new field compared to metal gearing that really started in the mid to late 50s with injection molded plastic, because it is one that a lot of people don’t understand,” said John Winzeler, Harold’s son and Winzeler Gear’s current owner and president. “R&D is an important part of our product design process. We don’t just manufacture parts to drawings. We assist our clients with complete product design, which includes running the stress calculations, selecting the material, creating the tolerances, and everything required to manufacture the part.”
According to Winzeler, his company has found that its larger customers have “outsourced their brains,” meaning that they are not focused on the design side or R&D of these types of products.
“To provide support to our clients and to bring innovative solutions to the table, we’ve embarked on an R&D program with our research and development laboratory that has been running for 15 to 20 years to understand the performance of gears through dynamic testing, and then differentiating and understanding the performance of the materials,” Winzeler said.
According to Winzeler, there’s a significant amount of data available on the strength and performance of materials in metal gearing; however, that data does not exist for plastics.
“We’re trying to better understand plastics, because in many cases, the data isn’t available to take material data and put it into gear-calculated computer formulas and get accurate information,” Winzeler said. “You’re much more predictable with metal than you are with plastic. With plastic gearing, it has a lot to do with the lubrication system. Whether there is a lubrication system or not, the lubrication system makes a huge difference in the durability or the load-carrying capability of the plastics.”
Of course, such great strides in R&D come at a cost, but Winzeler said he looks at it as a necessity if his company is going to be globally competitive and help its clients make differentiating projects.
“We have to be involved in R&D because our customers are not,” Winzeler said. “Where they may be working on systems testing, we’re working on individual gears and material knowledge. Most of our research is done with Bradley University in Peoria, Illinois, which has one of the better undergraduate engineering programs in the Midwest. We started out with undergraduate students, which led to projects that were worked on by graduate students, and now we have undergraduate students, graduate students, and professors helping run the research in concert with our engineers.”
As it is with Winzeler Gear, creativity is also a driving force at Penn State University’s Gear Research Institute (GRI), which has been conducting pre-competitive research in various industry-sponsored consortiums and single-client R&D programs since the 1980s. The majority of the institution’s experience is in component-level performance testing, including rolling contact fatigue, single tooth bending fatigue, single tooth impact, four square gear fatigue, scoring resistance, and loss-of-lube gear testing. In conjunction with the university’s Applied Research Laboratory (ARL)’s Drivetrain Technology Center, the two provide performance, metallurgical and metrological characterization, and root cause failure analysis services to the gear industry.
“We have uncovered problems that I like to call ‘opportunities for improvement’ for sponsors in all areas of manufacturing, from raw material quality issues to problems with material removal leading to insufficient case depth and problems with post processing techniques like shot peening, honing, or isotropic surface finishing,” said Aaron Isaacson, the managing director of the GRI and head of the Drivetrain Technology Center at the ARL. “Almost everything we do revolves around gear manufacturing and ways to make sure it is done properly.”
As an example, the Drivetrain Technology Center has recently developed a unique gear finishing process called Ausform finishing, which completes hardening and roll finishing in a single process that eliminates the need for grinding. The result is a gear with similar quality and bending fatigue strength, but superior contact fatigue performance.
According to Isaacson, the GRI and ARL have seen a great deal of interest recently in their loss of lubrication (or oil-off) test capability, both with roller specimens and gears.
“New requirements for increased flight time without oil in helicopter gearboxes have led to a lot of work in this area,” Isaacson said. “When a gearbox loses lubrication, the friction between the meshing teeth increases, resulting in higher heat generation. The oil system is the primary means of heat removal for the gears. Without oil, the heat generated leads to numerous problems in a very short time. We’ve been testing things such as low friction coatings to steels with very high tempering temperatures and everything in between.”
Additionally, Isaacson said that he and his teams have been working to improve the efficiency of meshing gears, including the reduction of friction.
“Regardless of industry, everyone cares about improving efficiency,” Isaacson said. “The auto industry wants to reduce fuel consumption and the aerospace industry wants to carry less oil or reduce the size of their cooling systems. Our test lab is equipped with roller and gear test rigs that are able to measure changes in efficiency, which often result from improving the surface finish, adding a low friction coating, changing the lubricant, adding a lubricant additive, or a variety of other possibilities.”