In this paper, a new electro-hydraulic variable valve actuator (EHVVA) (21) is presented. The EHVVA is capable of variable valve timing, lift,anddurationthroughcontrol ofactuationsolenoid valves and supply pressure with very low cost. Two frequently used lifts (high and low lifts) are achieved mechanically using a hydrau-lic lift controlled sleeve.
A Review of variable engine valve timing, SAE Paper 880386 (4) Nuccio, P.: Variable Valve Timing as a Means to Control Engine Load, FISITA 82071 (5) Lenz, H.: Initial test result of an electro-hydraulic variable-valve actuation system of a firing test, SAE Paper 890678 (6) Suzuki, J.: Study of improving Fuel Economy by Early Intake Valve.
In hydraulic system of injection machine, electro-hydraulic proportional flow valve is used to change complex variable pump output flow and power in order to adapt to load change and energy saving.In this paper ,it introduces the working principle of electro-hydraulic proportional flow valve and how control the complex variable pump.Variable valve technique can significantly improve the performance of the automobile engine and reduce pollution emission by varying valve timing, valve duration and valve lift. Variable valve system which is based on electro-hydraulic drive has the advantages of better stability, low noise and simple structure. In this paper, a variable valve system which is based on electro-hydraulic drive.FIAT is mass-producing the first fully variable intake valve train, which is based on electro-hydraulic valve drive (5, 6). The variable valve drive is one of the key technologies for fuel.
Explore Collection Variable Valve Optimization, 2008,2010. Search. Viewing 1 to 16 of 16. 1.. This paper presents the current research activity about an electro-hydraulic camless valve actuation system for internal combustion engines.
In this paper describes a new electro-hydraulic valve train systems, a research grade system used on single cylinder engines capable of meeting follows specifications: - Each valve can be fully independently controlled - Each valve have a variable valve left and can be latched at a steady lift positions.
A continuous variable valve timing and lift system by hydraulic volume adjustable (CVVTL) for both intake and exhaust valves of Spark Ignition (SI) engine is introduced in this paper. Unlike existing hydraulic variable valve systems, the CVVTL does not use the electro-hydraulic valves. A four-cylinder CVVTL prototype of engine cylinder head was built, and the valve movement laws of the.
A continuous variable valve lift (VVL) mechanism for a diesel engine is proposed in this research. The hydraulic mechanism, which consists of a driving plunger, a driven plunger, a hydraulic cylinder, and a hydraulic oil tank, is the key part of the VVL mechanism. Simulation is conducted to study the relationship between maximum valve lift and rotation angle of driving plunger.
Abstract: Taking the Woodward's UG-25plus electro-hydraulic governor for research object, this paper established mathematical model of the electro-hydraulic speed governing system of diesel engine. By means of simulink simulation, analyzed the main factors which affect dynamic characteristics of hydraulic actuator, emphatically Analyzed influence of damping ratio, natural frequency and flow.
In this paper, a new electro-hydraulic variable valve actuator (EHVVA) (9) is presented. The EHVVA is capable of variable valve timing, lift and duration through control of actuation solenoid valves and supply pressure with very low cost. Two frequently used lifts (high and low) are achieved mechanically using a hydraulic lift controlled sleeve.
This paper focuses on exploring the dynamics and control of an electro-hydraulic fully flexible valve actuation system. Challenges and approaches for developing variable valve actuation systems are first outlined and discussed. Dynamic model of the electro-hydraulic actuator was obtained based on experimental data.
In modern four-stroke automotive engine technology, variable valve timing and lift control offer potential benefits for making a high-performance engine. In this paper, a novel design named dual-mode electrohydraulic fully variable valve train (EHFVVT) for both engine intake and exhaust valves is introduced. The system is mainly controlled by either proportional flow control valves or.
This paper presents a detailed model of a novel electropneumatic valve actuator for both engine intake and exhaust valves. The valve actuator’s main function is to provide variable valve timing and variable lift capabilities in an internal combustion engine.
The Rexroth-SYDFE is an electro-hydraulic control system based on an axial piston variable displacement pump for controlling pressure, flow and power without throttling losses in the energy line. The advantages are robustness, high efficiency, energy efficiency as well as a dynamic and highly accurate regulation.
While a fully variable electro-hydraulic valve train system might be the 'ideal' solution technically for maximum flexibility in the timing and control of the valve events, its complexity, associated costs, and high power consumption make its implementation on low cost high volume applications unlikely.