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Over the past decades, the automotive industry has made significant efforts to improve engine fuel economy by reducing mechanical friction. Reducing friction under cold conditions is becoming more important in hybrid vehicle (HV) and plug-in hybrid vehicle (PHV) systems due to the lower oil temperatures of these systems, which results in higher friction loss. To help resolve this issue, a new internal gear fully variable discharge oil pump (F-VDOP) was developed. This new oil pump can control the oil pressure freely over a temperature range from -10°C to hot conditions. At 20°C, this pump lowers the minimum main gallery pressure to 100 kPa, thereby achieving a friction reduction effect of 1.4 Nm. The developed oil pump achieves a pressure response time constant of 0.17 seconds when changing the oil pressure from 120 kPa to 200 kPa at a temperature of 20°C and an engine speed of 1,600 rpm.

This paper reports the results of a study into a preview control that uses the displacement of the road surface in front of the vehicle to improve for front and rear actuator responsiveness delays, as well as delays due to calculation, communication, and the like. This study also examined the effect of a preview control using the eActive3 electric active suspension system, which is capable of controlling the roll, pitch, and warp modes of vehicle motion.

Understanding of the oil film formation mechanism around a piston skirt is very important to reduce the friction loss at piston skirt. We have investigated lubricant oil film behavior around piston skirt which is affected by piston slap under motoring condition. In this study, a cylinder liner of a commercial engine is displaced with a quartz cylinder. Photographic observations of oil film behavior between the cylinder liner and the piston skirt were performed with two kinds of methods; direct monochromatic photography and LIF (Laser Induced Fluorescence) image using a high speed camera. The oil film distributions were determined from oil boundary observed by the direct photography, and oil film thickness was estimated from the LIF intensity. Differences of the oil film distributions and the oil film thickness depending on piston shapes were investigated for four types of pistons.

Recently, plastic air intake manifold (PAIM) has been adopted into gasoline and diesel engines as standard equipment. The advantages of the PAIM are light mass weight, low cost, high thermal-insulation efficiency and reduction of air pressure loss compared with a metal air intake manifold. However, in order to bring the advantages of the PAIM into play, many issues including static burst, noise and vibration, and so on should be settled in its design process. In this paper, the performance prediction and application example of PAIM are introduced.

It is well known that the self-aligning torque decreases before lateral force is saturated. Focusing on this self-aligning torque change, an estimation method has been developed to detect the friction condition between steered wheels and road surface before the lateral force reaches the friction limit. The lateral grip margin (LGM) is defined based on the self-aligning torque change, which is obtained using the EPS torque and motor current information. The LGM is theoretically analyzed based on the tire model and experimentally verified through the full-scale vehicle test. Moreover, the estimated LGM is applied for the chassis control systems to improve the vehicle dynamics performance.

Exhaust emission regulation has become stricter year by year because of the global movements of environment protection. In consequence, turbocharger application to diesel engines became indispensable. Especially a variable geometry turbocharger (VGT) is perceived as the essential item. Of late years, the diesel engine has a trend of higher exhaust temperature to increase specific output. At the same time, needs of the turbocharger application to the gasoline engine has been rising again in order to reduce the size. In spite of this trend of the emission temperature increment, VGT of the variable nozzle vane type which is commonly available in the current market has problems of high temperature resistance due to its complex structure. AISIN SEIKI has developed a variable flow turbocharger (VFT), which is able to resolve those problems.

This paper describes the investigation into the contact pressure and incidental deformation on the contact surface of the piston skirt which comes in contact with the cylinder bore in operation. Focused on the single piston static tests in the first place, relationship between the contact pressure on said skirt and the strains developed inside the skirt, and the relationship between the deformation of skirt face and the strains inside the skirt were studied. Then, the dynamic contact pressure onto the skirt in operation and the amount of deformation were calculated based on the relationships mentioned above using the factor of dynamic strains measured on an engine in operation. The deformation of skirt calculated using said dynamic strains was verified by the direct measurement of the skirt deformation. It was demonstrated that the thrust side of a piston skirt was largely deformed due to enlarged contact pressure caused by the piston slap subsequent to firing top dead center.

As a process that enables the high-speed and continuous forming of lengthy materials with a constant cross-sectional configuration, roll forming offers much higher productivity than the stamping process. However, in case a change must be made to the shape of the cross section, the material must normally be stamped or joined with a part containing a separate shape. This affects productivity, increases the number of pieces, and degrades the material's appearance. This report describes the roll-forming technology that we developed, in which the cross section of the material can be changed gradually. This method adopts a system which uses a movable and rotatable roll-stand that enables high-speed, continuous roll-forming processes.

While exhaust gas emission standards are becoming severe, turbochargers which have a good performance and wide operating range are required. At Aisin Seiki, we have started development of the SJ (swirl jet) turbocharger to cope with these requirements without increasing costs. In this paper, we describe the features and effects of the SJ turbocharger.

In this paper, we discuss vehicle directional stability and introduce advanced stability control (ASTC) to stabilize the vehicle during severe cornering. Vehicle behavior in a transient steering condition during severe cornering was analyzed by computer simulation. It was found that applying an external yaw moment makes the vehicle more stable. The effect of controlling the brake force response is also evaluated by simulation to determine the brake actuator response criteria. The actual vehicle test was performed with a pylon slalom using a hydraulic brake actuator. It is verified that the ASTC stabilizes the vehicle for transient steering maneuvers.

Development of a system which utilizes technology for the recognition of a vehicle's surroundings. Research is currently taking place in many countries, the goals of which are to improve a vehicle's safety and convenience by reducing driver strain through the automation of the recognition, judgment, and operation capabilities that are needed when driving an automobile. To recognize the vehicle's surroundings, we have adopted an image sensor system which offers superior three-dimensional recognition capabilities. In this paper, we will introduce a inter vehicle distance control system which controls the vehicle's throttle and braking functions by detecting the position of the driving lane and the distance to the vehicle in front based on the images obtained by a CCD camera.

Automating the inspection of the piston combustion chamber volume is difficult and prevents establishing an unmanned machining process of the piston in the future. So, we developed an inspection technique which uses a Range Finder, non-contact visual sensor, and calculate the chamber volume by integrating 3D position data. We applied this real-time measurement technique which enables 100 % inspection to our production lines. Then, we developed the “Defect Free Production Line”, which calibrates itself by feeding back the measured volume data to the machining process. Our paper will explain this inspection technique and our “Defect Free Production Line”.

Aiming at improved reliability and cost reduction of position sensors for automobiles, we tackled with the challenge of developing long life contact type potentiometer which has a simple construction and cost advantage. We made clear the wear characteristics of the resistor materials and the mechanism how noise occurs, and developed a long life, low noise resistor material, and the double - layer resistor structure which has excellent characteristic in durability. We also clarified the ways of using brushes according to applications through the investigation of the relationship between the contact shape and the amount of wear of the resistor. Based on these investigation, we have developed a highly reliable throttle position sensor and a long life vehicle height sensor.

Recently two-mass flywheels have adopted in various types of engines to decrease torsional engine vibrations. A two-mass flywheel has a resonance frequency below the idle speed. Thus, it must be provided with an energy dissipating mechanism to avoid a resonance problem. Consequently, flywheel's damping effectiveness at practical engine speeds is decreased because the energy dissipating mechanism restricts relative displacement of the two-mass flywheel. In this work, a new prototype two-mass flywheel was evaluated and found to be effective in improving two important qualities of such devices; (1) its ability to decrease torsional vibrations (2) its ability to avoid resonance problems during engine startup.