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.
Progress in Camless Variable Valve Actuation with Two-Spring Pendulum and Electrohydraulic Latching
Sae Int. J. Engines
SAE 2013 World Congress & Exhibition ; 2013
Sae International Journal of Engines ; 6 , 1 ; 319-326
2013-04-08
8 pages
Conference paper
English
Progress in Camless Variable Valve Actuation with Two-Spring Pendulum and Electrohydraulic Latching
British Library Conference Proceedings | 2013
|Camless Variable Valve Actuation Designs with Two-Spring Pendulum and Electrohydraulic Latching
British Library Conference Proceedings | 2007
|Camless variable valve actuation designs with two-spring pendulum and electrohydraulic latching
Automotive engineering | 2007
|Camless Variable Valve Actuation Designs with Two-Spring Pendulum and Electrohydraulic Latching
SAE Technical Papers | 2007
|Adaptive lift control for a camless electrohydraulic valvetrain
Automotive engineering | 1998
|