Electromagnetic Valve Actuation System With Two Configurations

2009 ◽  
Author(s):  
Rudolf Seethaler ◽  
Konrad Duerr
Keyword(s):  
High Speed ◽  
Digital Simulation ◽  
Valve Train ◽  
Electromagnetic Valve ◽  
High Speed Engine ◽  
Actuation System ◽  
Control Scheme ◽  
Cam Profile ◽  
Actuation Devices ◽  
Valve Actuation

Electromagnetic valve actuation systems for automotive combustion engines must provide extremely fast valve motion when the engine speed is high, but they also need to ensure low valve seating velocities during engine idle. These two constraints are difficult to combine in conventional spring assisted electromagnetic valve actuation devices that operate at a fixed resonance frequency. This paper focuses on a mechanism with two distinct configurations for low and high speed engine operations respectively. The mechanism is based on two pivoting cams. The synthesis of the cam profile ultimately determines the performance of the actuation system. An algorithm is presented that provides a time optimum cam profile for the high speed cam. The low speed cam is designed to allow for servo control of the valve system. A control scheme that aims to minimize electric losses in the drive system is also introduced. Both the cam synthesis algorithms and the control algorithm are applied to a typical automotive valve train and a digital simulation is used to validate the effectiveness of the mechanical cam design and control scheme.

Effects of design and operating parameters on the static and dynamic performance of an electromagnetic valve actuator

2003 ◽  
Vol 217 (3) ◽  
pp. 193-201 ◽  
Author(s):  
S-H Park ◽  
J Lee ◽  
J Yoo ◽  
D Kim ◽  
K Park
Keyword(s):  
Simulation Model ◽  
New Technology ◽  
Dynamic Performance ◽  
Operating Parameters ◽  
Computer Simulation Model ◽  
Neutral Position ◽  
Electromagnetic Valve ◽  
Actuation System ◽  
Si Engines ◽  
Actuation Devices

The electromagnetic valve (EMV) actuation system is a new technology for improvement in fuel effciency and reduction in emissions in spark ignition (SI) engines. It can provide more flexibility in valve event control compared with conventional variable valve actuation devices. However, a more powerful and effcient actuator design is needed for this technology to be applied in mass production engines. This paper presents the effects of design and operating parameters on the static and dynamic performances of the actuator. Employing the finite element method (FEM), the flow pattern of the magnetic flux is analysed and the resultant magnetic forces of several cases of core and armature designs are calculated. A computer simulation model has been set up to identify the dynamic behaviour of the EMV system. The effects of external disturbances such as cylinder pressure, armature neutral position and current supply time are also analysed. To verify the accuracy of the simulation model, an experimental study is also carried out on a prototype actuator. It is found that there is relatively good agreement between the experimental data and the results from the simulation model. The newly designed actuator is successfully operated on the test bench up to about 6000 r/min, which is the range of rated speed of most production SI engines. Through the whole speed range, the actuator maintains good performance in valve timing and event control.

Nonlinear Transient Response of a High Speed Driven Valve System and Stresses in Valve Springs for Internal Combustion Engines

1989 ◽  
Vol 111 (3) ◽  
pp. 264-271 ◽  
Author(s):  
K. Nagaya
Keyword(s):  
High Speed ◽  
Internal Combustion Engines ◽  
Three Dimensional ◽  
Beam Theory ◽  
Internal Combustion ◽  
Valve Train ◽  
Combination Method ◽  
Combustion Engines ◽  
Valve System ◽  
Cam Profile

This paper presents a method for solving the dynamic response problems of a driven valve system and the stress problem of valve springs for internal combustion engines. In this system there is hysteresis behavior in the spring constants during the rotation of the cam shaft. To treat this nonlinearity, the rigidity of each section is assumed to be one of a partly linear spring. For the valve trains, the cam profile is complex in general. To treat a general cam profile, this paper applies a combination method of the Fourier expansion, the Laplace transform and the analytical connection methods, and gives a response of valve trains. This paper also presents a theoretical result for the stresses in the valve spring due to the motion of the valve train based on the three dimensional curved beam theory.

Analysis and Optimization of High-Speed Gasoline Engine Cam Profile

2013 ◽  
Vol 278-280 ◽  
pp. 184-188
Author(s):  
Yuan Li ◽  
Jing Yang ◽  
Ke Li
Keyword(s):  
Contact Stress ◽  
High Speed ◽  
Gasoline Engine ◽  
Simulation Software ◽  
Valve Train ◽  
Intake Valve ◽  
Abnormal Sound ◽  
Cam Profile ◽  
Overall Performance ◽  
Train Simulation

In this paper, to solve the problems of tappet damaged seriously and mechanisms abnormal sound that existed in a high-speed gasoline engine, the valve train simulation software AVL-TYCON was applied to perform both kinematic and dynamic analysis. The results show that the original speed and acceleration curves of intake valve train are not smooth enough and the contact stress is excessive high. The intake cam was then redesign to improve the overall performance of the engine, and results are verified through experiments

Improve Dynamic Performance on High Speed by Application of Electromagnetic Valve Actuation

2013 ◽  
Vol 462-463 ◽  
pp. 826-829
Author(s):  
Jiang Tao Xu
Keyword(s):  
Theoretical Basis ◽  
High Speed ◽  
Dynamic Performance ◽  
Electromagnetic Valve ◽  
Air Intake ◽  
Opening Stage ◽  
Variable Valve ◽  
Valve Actuation

This paper base on electromagnetism valve technology, the intake valves of a car driven by electromagnetic valve, by cooperating average torque of engine with prototype by 6000 RPM engine, then found that the average torque can be increased by 5.679% after changing the intake valves with electromagnetic valves. The increasing torque contributed to increasing the air intake in the opening stage and off stage improved, and provided a theoretical basis for the promotion of the electromagnetic variable valve in automotive.

Design of Cam Profile Based on Miller-Cycle

2010 ◽  
Vol 43 ◽  
pp. 588-593
Author(s):  
Sheng Li Wei ◽  
Wu Qiang Long ◽  
Zhong Wang ◽  
Xian Yin Leng
Keyword(s):  
Diesel Engine ◽  
High Speed ◽  
Optimization Design ◽  
Valve Train ◽  
Miller Cycle ◽  
Intake Valve ◽  
Closing Time ◽  
Order Polynomial ◽  
Cam Profile ◽  
General Method

The necessity which high-order polynomials are used for optimization design of cam profile is analyzed in valve train of high-speed engines. Basing on the basic idea of Miller-cycle delayed intake valve closing time to reduce the compression ratio, this method is used for re-optimize design of the cam profile in CY4D47 diesel engine. The general method is given by the five-order polynomial. So, the improved cam profile equations can be obtained, then, the lift, velocity, acceleration and Jerk curves are got, lastly, the cam profile are drew by AutoCAD soft.

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