A Fully Flexible Valve Actuation System for Internal Combustion Engines

In this study, the mechanical design of a fully flexible valve actuation system (FFVA) for intake valves of naturally aspirated internal combustion engines is optimized. The original FFVA design used a connecting rod in order to transform the rotating motion of the actuator to translating motion of the valve. In the improved design introduced here, the connecting rod is replaced by a flexible linkage. This step is taken in order to eliminate wear and play in the mechanical connections. A detailed design procedure is presented to optimize the heavy fatigue load on this element. Simulations and experimental tests are carried out in order to validate the system performance. It is shown that valve trajectory and energy consumption of the actuation system obtained by simulations are consistent with those observed experimentally. The present redesigned FFVA system then provides more reliable valve motion than previously shown designs.

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Improved Mechanical Design for a Fully Variable Electromechanical Valve Actuation System for Internal Combustion Engines

Volume 11: New Developments in Simulation Methods and Software for Engineering Applications; Safety Engineering, Risk Analysis and Reliability Methods; Transportation Systems ◽

10.1115/imece2010-38711 ◽

2010 ◽

Author(s):

Hossein Rokni Damavandi Taher ◽

Rudolf J. Seethaler ◽

Abbas S. Milani

Keyword(s):

Internal Combustion Engines ◽

Mechanical Design ◽

Experimental Tests ◽

Internal Combustion ◽

Combustion Engines ◽

Mechanical Vibrations ◽

Actuation System ◽

Ohmic Losses ◽

Valve Motion ◽

Valve Actuation

This study aims to improve the mechanical design of a fully flexible valve actuation system (FFVA) for intake valves of internal combustion engines. Optimization procedures for increasing the reliability and efficiency of the mechanical design of the FFVA system are presented. Simulations and experimental tests are carried out in order to validate the system performance. It is shown that position, velocity and acceleration of the valve obtained by simulations are consistent with those observed experimentally. Furthermore, it is observed that the mechanical vibrations are considerably reduced in the redesigned FFVA system. As a result, current levels and ohmic losses in the electric motor are also reduced. The present redesigned FFVA system then provides more reliable valve motion and better efficiency than the previously shown design [25].

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Friction and Pumping Losses Estimation in Flex Internal Combustion Engines with Variable Valve Actuation System Using Chamber Pressure Measurement

10.4271/2012-36-0363 ◽

2012 ◽

Cited By ~ 1

Author(s):

Lucymara R. Alvarenga ◽

Marcela E. Vianna ◽

Marcio C. Pierobom ◽

Rodrigo V.G. Andrade

Keyword(s):

Pressure Measurement ◽

Internal Combustion Engines ◽

Internal Combustion ◽

Chamber Pressure ◽

Combustion Engines ◽

Variable Valve Actuation ◽

Actuation System ◽

Variable Valve ◽

Valve Actuation

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A Cogging Torque Assisted Motor Driven Valve Actuation System for Internal Combustion Engines

Volume 1: 15th International Conference on Advanced Vehicle Technologies; 10th International Conference on Design Education; 7th International Conference on Micro- and Nanosystems ◽

10.1115/detc2013-13182 ◽

2013 ◽

Cited By ~ 1

Author(s):

Bradley A. Reinholz ◽

Rudolf J. Seethaler

Keyword(s):

Internal Combustion Engines ◽

High Efficiency ◽

Acoustic Emissions ◽

Internal Combustion ◽

Performance Criteria ◽

Combustion Engines ◽

Cogging Torque ◽

Actuation System ◽

Stringent Performance ◽

Valve Actuation

Electromechanical valve actuation (EVA) for internal combustion engines promises to significantly improve engine efficiency and lower emissions by reducing pumping losses and allowing for novel combustion strategies. However, current designs have not been able to meet the stringent performance criteria for reliability, efficiency, acoustic emissions, weight, and cost that are required by the automotive industry. This paper describes a novel cogging torque assisted motor driven (CTAMD) valve actuation system that promises to meet both the performance and robustness requirements. In contrary to existing EVA systems that recover the kinetic valve energy using a mechanical spring system, the CTAMD system recovers kinetic energy in a magnetic field. This allows for high efficiency while maintaining a simple and elegant electromechanical design. This paper describes the characteristics of CTAMD systems and outlines an electromechanical design for such a system. Then computer simulations of the proposed design are used to demonstrate the expected performance of the system. Finally, the simulated results are compared to other EVA systems to highlight the anticipated improvements.

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Experimental Validation of a Cogging Torque Assisted Valve Actuation System for Internal Combustion Engines

IEEE/ASME Transactions on Mechatronics ◽

10.1109/tmech.2015.2432100 ◽

2015 ◽

pp. 1-1 ◽

Cited By ~ 5

Author(s):

Bradley Reinholz ◽

Rudolf Seethaler

Keyword(s):

Internal Combustion Engines ◽

Experimental Validation ◽

Internal Combustion ◽

Combustion Engines ◽

Cogging Torque ◽

Actuation System ◽

Valve Actuation

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A Continuously Variable Poppet Valve Actuator for Internal Combustion Engines

Proceedings of the Institution of Mechanical Engineers Part A Power and Process Engineering ◽

10.1243/pime_proc_1986_200_026_02 ◽

1986 ◽

Vol 200 (3) ◽

pp. 187-195 ◽

Cited By ~ 11

Author(s):

S J Charlton ◽

M Shafie-Pour

Keyword(s):

Internal Combustion Engines ◽

Internal Combustion ◽

Combustion Engines ◽

Finite Element Program ◽

Rigid Body Dynamic ◽

Poppet Valve ◽

Actuation System ◽

Valve Motion ◽

Element Program ◽

Body Dynamic

The paper describes a continuously variable poppet valve actuation system which may be applied to internal combustion engines to render the valve motion controllable while the engine is running. The first phase of a programme to develop the device is described. The results of a rigid-body dynamic analysis are presented followed by a dynamic simulation of the mechanism using a proprietary finite element program. These give an insight into its operation and clarify some of the problems to be solved if the device is to be successfully applied.

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Review of Advancement in Variable Valve Actuation of Internal Combustion Engines

Applied Sciences ◽

10.3390/app10041216 ◽

2020 ◽

Vol 10 (4) ◽

pp. 1216 ◽

Cited By ~ 1

Author(s):

Zheng Lou ◽

Guoming Zhu

Keyword(s):

Internal Combustion Engines ◽

Internal Combustion ◽

Combustion Efficiency ◽

Combustion Engines ◽

Mechatronic Systems ◽

Variable Valve Actuation ◽

Increasing Demand ◽

Electro Magnetic ◽

Variable Valve ◽

Valve Actuation

The increasing concerns of air pollution and energy usage led to the electrification of the vehicle powertrain system in recent years. On the other hand, internal combustion engines were the dominant vehicle power source for more than a century, and they will continue to be used in most vehicles for decades to come; thus, it is necessary to employ advanced technologies to replace traditional mechanical systems with mechatronic systems to meet the ever-increasing demand of continuously improving engine efficiency with reduced emissions, where engine intake and the exhaust valve system represent key subsystems that affect the engine combustion efficiency and emissions. This paper reviews variable engine valve systems, including hydraulic and electrical variable valve timing systems, hydraulic multistep lift systems, continuously variable lift and timing valve systems, lost-motion systems, and electro-magnetic, electro-hydraulic, and electro-pneumatic variable valve actuation systems.

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