Electric Vehicle Transmission System

The booming development of the electric vehicle industry has driven demand for high-efficiency, low-noise gear transmission systems. However, most domestic gear manufacturers still rely on traditional processing methods, resulting in a technological gap compared to international standards. To address this, AIM-HI has actively pursued technology upgrades by developing advanced gear processing technologies such as dry cutting and power skiving. We have also introduced closed-loop manufacturing techniques to enhance gear design and analysis capabilities, aiming to develop high-efficiency, low-noise gear transmission systems and narrow the gap with global leaders.
Additionally, we emphasize the development of domestically produced equipment, aiming for high-efficiency, low-carbon manufacturing using self-developed advanced machinery. We have introduced sophisticated gear measurement and inspection equipment to improve product quality and have actively promoted industry collaboration. These efforts aim to foster cooperation among domestic gear manufacturers for joint development of high-performance gear systems, integrating resources to create greater industrial value. AIM-HI has already initiated collaboration talks with several machine tool manufacturers, seeking to accelerate R&D and industrial applications through close industry-academic cooperation and boost the international competitiveness of Taiwan’s electric vehicle gear systems.
In 2024, our team, in collaboration with ITRI, successfully developed new differential gears for heavy-duty vehicles and manufactured them using self-developed machines. The bevel gear achieved a module of 9.5 mm and a gear cutting precision of DIN 6, surpassing international brands which offer module 7 mm at the same standard. Using dry cutting — an efficient and low-pollution method — the processing time was reduced to one-third, and the cutting force increased from 150Nm to 250Nm, showcasing the technical capability of our in-house gear machines and green manufacturing processes. We also researched gearbox design, contact pattern planning, and multi-axis toolpath programming, using Siemens controllers to establish a data tracking system that records and stores ten types of cutting data in CSV format for future AI learning. In power skiving, we tested various gears used in EVs, robots, and planetary systems — including external spur gears, internal gears, and face gears — and produced detailed measurement and surface contact analysis reports.
Key Technologies in 2024:

1. Low-Carbon, High-Efficiency Gear Manufacturing and Quiet Gear Design
   For EV reducers requiring high-speed, high-torque, and quiet gear features, we adopted additive manufacturing for gear blanks followed by efficient machining to enable smart manufacturing and enhance production efficiency and innovation. We have developed gear calculation, design, and manufacturing methods, along with efficient power skiving techniques, and published several SCI journal papers and conference reports.
2. Self-Developed Machinery and Smart Manufacturing Applications (4 Machines Completed)
   By using self-developed gear machines, we created multi-axis intelligent processing technologies and designed low-noise, high-precision transmission components through industry collaboration. These high-efficiency techniques reduce processing time and costs. We have completed the domestic development of four gear machines and are preparing two more models focused on low-pollution, high-efficiency production.
3. Gear Pair Inspection and Final Product Validation
   We used high-precision gear measuring instruments to analyze gear tooth topography and fed error data back to the manufacturing process to correct tool paths in a closed-loop system, ensuring quiet gear designs. Further testing included gear meshing, noise analysis, and vibration and temperature assessments of assembled gearboxes. We modified reducer designs based on real-world use cases and established a complete testing protocol to ensure product quality and performance.