Development of Plastic Gear for Power Transmission : Economical Methods for Increasing Load-carrying Capacity

Loading capacity of POM gear under oil lubrication

“…For small-lot gear production, mechanical cutting is usually used considering the production cost, which can reduce the cost of gear molds compared to injection molding. On the contrary, polymer gears in mass production can be processed by injection molding to reduce manufacturing costs (Terashima et al, 1986). Based on the preliminary research on the durability of injection molded POM gears (Lu et al, 2020), this paper discusses the fatigue performance and failure modes of POM gears processed by mechanical cutting.…”

“…On the other hand, the lubricating oil had a certain thickness of the oil film formed on the meshing tooth flank, which not only reduced the friction, but also avoided direct contact between the gears to a certain extent and protected the integrity of the POM gear tooth surface. The experimental results are compared with the durability test results of injection molded POM gears under oil lubrication provided by FZG researchers (Terashima et al, 1986). Compared with the machined POM gear in this experiment, the failure mode of FZG injection molded POM gear was different.…”

“…due to their relatively low manufacturing cost, lower operating noise and vibration performance, and material self-lubrication (Smith and Ulrich, 2012). With the application of new materials, the optimization of manufacturing processes, and the development of various reinforcement methods such as fibers or particles, the loadbearing capacity of polymer gears has been gradually improved, so that it can maintain the original excellent performance as well as meet the needs of medium and low power transmission fields such as automatic transmissions and small engines (Terashima et al, 1986;Kapelevich and McNamara, 2005). In recent years, as the demand for vibration and noise reduction in the transmission system has become stronger, the contradiction between the strength of the polymer gear and the demand in the transmission still cannot be balanced, and the fatigue strength of the polymer gear is still a great challenge in the application of polymer gears in the transmission.…”

“…Currently, POM gears account for up to 70% of the polymer gear market share (Walter, 2004;Jaster, 2012). Many studies related to POM gears show that POM gears have great potential in the field of high-power transmission (Terashima et al, 1986;Hasl et al, 2018). Kalin and Kupec (2017) studied the influence of temperature on the service performance of POM gear under dry operation and reported that the fatigue life of POM gear could be significantly improved with relatively low temperature.…”

“…It can be seen from the table that the failure modes of POM gear are various from that of other materials under the same working condition, meanwhile, the failure mode of POM gears might also change according to different working conditions. Mao et al,1996;Mao, 2007;Mao et al,2009 STEEL gear-POM gear Oil lubrication Tooth root breakage Terashima et al, 1986 Studies have shown that oil lubrication can improve the operation of POM gears, thereby improving the carrying capacity and reliability of POM gears (Yu et al, 2020a;Hasl et al, 2019), and the influence of oil lubrication on the performance of POM gears needs further study. This paper analyzes the main failure characteristics of gears under oil Zhong, Song, Liu, Wei and Lu, Journal of Advanced Mechanical Design, Systems, and Manufacturing, Vol.16, No.1 (2022) lubrication conditions through experimental research.…”