Abstract

Hydraulic Continuously Variable Transmissions (“CVT”) have a large capacity for power transmission and have achieved proven results in industrial machines. Research was conducted on hydraulic CVT for use in passenger cars with large engine displacement, particularly in the areas of fuel economy performance, high-speed performance and quietness where passenger cars have higher demands compared to industrial machines. An HMT (Hydro Mechanical Transmission), which has the highest efficiency of all hydraulic CVT, was adopted to improve efficiency at cruising which greatly affects fuel economy when cruising at high speeds. In addition, the lock-up brake mechanism and the hydraulic pump and motor portions were improved to reduce agitation, resulting in a 6% improvement in efficiency when cruising at 50 mph. The hydraulic motor rotates at high speed during high-speed cruising, but centrifugal force has little effect and prospects for durability were obtained by adopting a bowl type slipper and improving the cooling method. A method for reducing noise was also derived by focusing on fluctuations of swash plate movement, which are correlated with noise.

References

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Author (organization or company)

• Takashi IINO（Tochigi R&D Center）
• Akihito OKUDA（Tochigi R&D Center）
• Kazuaki SAKAI（Tochigi R&D Center）
• Mikihiro TAKANO（Tochigi R&D Center）
• Tetsushi ASANO（Tochigi R&D Center）
• Koichi FUSHIMI（Tochigi R&D Center）
• Masashi TANAKA（Tochigi R&D Center）

Publication Information

Article of Honda R&D Technical Review Vol.14 No.1 (57 - 66)

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Citation Information