Toyota’s New Hybrid Unit “L4A0”

Toyota developed a new hybrid unit “L4A0” for the new Tundra, which creates both good drivability and environmental performance. To ensure off-road, towing performance and typical truck driving characteristics, the unit is based on a transmission with a torque converter and a multi-plate lock up clutch, with a motor-generator and K0 clutch installed between the engine and transmission. The motor-generator and K0 clutch are built into a module, making it possible to create new hybrid units by combining the module with various transmissions. The unit features many different motor controls. For example, in the case of step-in acceleration input, in order to achieve the desired output torque, typically a kick-down shift is necessary [1]; however, by utilizing “L4A0” both high response and high power output is achieved even without a kick-down shift. This is accomplished by assisting the engine with the motor-generator even when the engine torque is delayed at low engine speeds. Simultaneously, this contributed to better fuel economy by allowing the engine to work at optimum speeds [1-3]. Another feature is the high-response and shock-less engine start that is achieved by cranking the engine with the motor-generator via the K0 clutch.

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  • Supplemental Notes:
    • Abstract reprinted with permission of SAE International.
  • Authors:
    • Tan, Guodong
    • Ikemura, Masashi
    • Hasegawa, Yoshio
    • Ohki, Takao
    • Baba, Masayuki
    • Nakamura, Atsuro
    • Herring, Craig
    • Niinomi, Atsushi
    • Hamano, Makoto
    • Mizoguchi, Yasuhiro
  • Conference:
  • Publication Date: 2022-3-29

Language

  • English

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Filing Info

  • Accession Number: 01841822
  • Record Type: Publication
  • Source Agency: SAE International
  • Report/Paper Numbers: 2022-01-0656
  • Files: TRIS, SAE
  • Created Date: Apr 6 2022 2:18PM