This content is not included in your SAE MOBILUS subscription, or you are not logged in.
Progress in Camless Variable Valve Actuation with Two-Spring Pendulum and Electrohydraulic Latching
- Zheng David Lou - Jiangsu Gongda Power Technologies Ltd. ,
- Qiangquan Deng - Jiangsu Gongda Power Technologies Ltd. ,
- Shao Wen - Jiangsu Gongda Power Technologies Ltd. ,
- Yunhai Zhang - Jiangsu Gongda Power Technologies Ltd. ,
- Mengjin Yu - Jiangsu Gongda Power Technologies Ltd. ,
- Ming Sun - Jiangnan University ,
- Guoming Zhu - Michigan State University
ISSN: 1946-3936, e-ISSN: 1946-3944
Published April 08, 2013 by SAE International in United States
Citation: Lou, Z., Deng, Q., Wen, S., Zhang, Y. et al., "Progress in Camless Variable Valve Actuation with Two-Spring Pendulum and Electrohydraulic Latching," SAE Int. J. Engines 6(1):319-326, 2013, https://doi.org/10.4271/2013-01-0590.
Camless Variable Valve Actuation (VVA) technologies have been known for improving fuel economy, reducing emissions, and enhancing engine performance. VVA can be divided into electro-magnetic, electro-hydraulic, and electro-pneumatic actuation. A family of camless VVA designs (called LGD-VVA or Gongda-VVA) has been presented in an earlier SAE publication (SAE 2007-01-1295) that consists of a two-spring actuation, a bypass passage, and an electrohydraulic latch-release mechanism. The two-spring pendulum system is used to provide efficient conversion between the moving mass kinetic energy and the spring potential energy for reduced energy consumption and to be more robust to the operational temperature than the conventional electrohydraulic actuation; and the electrohydraulic mechanism is intended for latch-release function, energy compensation and seating velocity control. This paper presents the prototype design of a variable valve-time and two-lift LGD-VVA with bench and engine test results. The designed actuator is able to achieve 3 ms opening and closing response time with satisfactory valve seating velocity and low energy consumption. This is all achieved with a cost-effective design and open-loop control.