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As automotive electronic systems aiming for a safe and secure automobile society continue to develop, the control specifications of the ECU are becoming increasingly complex. When attempting to validate control specifications that cooperatively control different control specifications, control specification developers must consider various validation viewpoints. They narrow down the validation viewpoints based on rules from past experience, describe timing charts, and validate the specifications. However, due to complicated specifications, empirical rules do not pass, and specification mismatches are often found after actual systems completion. On the other hand, a block diagram simulator is a tool to verify control specifications. Since these tools are aimed at modeling and verifying the system design, it is efficient to describe how to implement the system. However, first it is necessary to verify the consistency between the model and the specifications.

Diesel Particulate Filter (DPF) has become a standard after treatment device to remove particulate matter (PM) exhausted from diesel engines. Cordierite and Silicon Carbide are commonly used materials for construction of DPF. Customers, however, require further improvement concerning the performance of DPF. Cordierite has low limitation of PM loading capacity due to its lower thermal shock resistance, while silicon carbide has higher back-pressure due to its larger grain size. Generally, silicon nitride which is one of the typical thermal resistant ceramics has high mechanical strength and thermal shock resistance. Kubota's development of porous silicon nitride is structured with controlled small grain crystals of elongated hexagonal systems. This enables high PM filtration efficiency with low back pressure increase and higher filtering efficiencies for smaller PM.

Reducing the oxides of nitrogen (NOx) and particulate matter (PM) from Diesel engine exhaust gas has become very important problem in view of the protection of environment and the saying energy. But it is difficult to reduce both emissions significantly at the same time by engine modifications and operating condition control. Because, their characteristics have a trade off relation. Therefore many investigators are studying the aftertreatment technique of Diesel engine emissions such as a PM trap filter, EGR, etc. The aftertreatment technique is expected that engine operating condition limits will be loose and engine efficiency will be improved. A few years ago, Iwamoto showed that Zeolite catalyst could reduce the NOx with hydrocarbon reducing agents under oxygen rich condition[1]*. After that, many researchers have been investigating Zeolite catalysts[2]-[4].

This paper presents some of our various test data, newly developed testing method and valuable field data about reliability of Variable Geometry Turbine (VGT) turbocharger. Influential parameters are reviewed item by item. Establishing durability of VGT nozzle and link system is essential for developing VGT turbocharger. However that is not enough to achieve reliability target of VGT turbocharger system only since operating range and conditions of VGT turbocharger is different from conventional system. It was also necessary to optimize other components such as thrust bearing, sealing mechanism and compressor wheel etc. to severer conditions than conventional system.

The use of automatic transmissions is continually increasing because of their ease of operation. Transmission performance requirements that have become more important in recent years include smooth shift quality and a shift schedule that matches the driver's intentions. An electronically controlled automatic gearbox, which sets the shift schedule according to the vehicle speed and throttle valve opening, provides a dramatic improvement in shift quality over its hydraulically controlled counterpart. However, even with an electronically controlled automatic transmission, shift hunting occurs when driving uphill or towing an object Based on the use of fuzzy logic, a technique has been developed for estimating running resistance, represented by the road gradient. This technique has been incorporated in a new shift schedule control method that eliminates shin hunting Research is now under way on a fuzzy logic technique for inferring the driver's intention to accelerate

Many kinds of turbochargers have been mounted to engines for automotive use. Now, conventional, wastegated, variable geometry turbocharger and many systems are available. These turbocharged engines have many advantages, such as a high specific output power and good efficiency. Diesel engines are more suitable to turbocharging than spark ignition engines. But recently for a growing interest in acid rain and green house effect problems, regulations of engine exhaust gas emission have been tightened in Japan, USA and Europe. NOx and particulate matter from automotive engines must be reduced. In the USA, transient response of boost pressure has been important also for the EPA transient test mode. To cope with these regulations, diesel engine manufacturers demand turbocharger makers to provide far higher boost pressure than ever to supply more air to engines to improve combustion process.

A large scale graphic vacuum fluorescent display was developed. The display is packaged in a panel size of 54.0 x 350.0 (mm) with 24 x 264 pixels (11 digits when a character consists of 24 x 24 pixels). Self-standing grid system was adopted to make finer grid divisions. To attain uniform luminance and prevent cross talk, the quadruplex anode matrix system was utilized. Wire dampers were used as an anti-vibration measure. To prevent thermal deformation of the grid, glass paste was applied to cover the grid bonding.

The adoption of the newly developed self-standing grid construction allows a more flexible layout of the electrodes and location of the grids, while reducing the number of grid leads. These improvements make it possible to minimize the lead pitch and to increase the flexibility of the lead out position. For example, the leads of the new clip-on type displays will allow them to be condensed on one side of the display, while in the case of the ordinary Vacuum Fluorescent Displays (VFDs) the leads are located on both the top and the bottom. By connecting flat cables to the minimized leads, a clip-on VFD was successfully developed, which is excellent in terms of mounting flexibility, circuit maintenance, system cost and function. The manufacturing process and features of the clip-on VFD will be described later.

Vacuum Fluorescent Displays (VFD's) are being used widely as the informational display panel in the automobile because they are a self-emissive, high luminance display device that feature crisp and easy-to-read images. This paper reports on the development of a VFD that can be directly driven by the outputs of a single chip microcomputer operating from a 12 volt supply. This system is most ideal for automotive applications.

A. closed loop control system has been developed to minimize vehicle acceleration fluctuation during power-on upshift of an automatic transmission. This system senses the revolution speed of torque converter turbine runner, and controls the hydraulic pressure of clutch actuating cylinder during the shift sequence using a linear solenoid type electro-hydraulic pressure modulation valve so as to regulate the turbine runner speed on schedule. By the torsional rigidity of drive train, shorter torque phase brings smoother shifting. Opposing requirement exist to complete the torque phase quickly and to carefully limit clutch torque capacity. Discernment of clutch facing contact using pressure sensors is able to satisfy the requirement.

To produce high quality appearance interior parts, precise pattern forming or gloss reduction of three-dimensional door trim cover materials are utilized. In the preparation of formed trim cover using polyvinyl chloride (PVC), prior pattern forming on original cover material or post-pattern forming with vacuum forming dies are employed. In the latter case, the die is usually made of epoxy resin. Although vacuum holes are prepared on the resin die as necessary, the lack of uniformity in air permeability causes inferior pattern transferability. In this development, special porous ceramic die is used as die material so that trim cover material can be evenly sucked through the fine pores on its surface. As a result, a door trim forming die of superior pattern transferability has realized.

It has been reported by several researchers that the L-jetronic fuel injection system offers better idle speed stability than the D-jetronic one in port fuel injection engines. However, the volume between the throttle valve and the intake valves in the L-jetronic system acts as a first order lag element in the system and causes air-fuel ratio fluctuation which, in turn, induces idle speed hunting under certain conditions. This study employs computer simulation to determine the influence of three parameters on idle speed stability: (1) flywheel inertia, (2) intake manifold volume, and (3) air-fuel ratio calibration. It also explores means of improving idle speed stability by controlling the air-fuel ratio and ignition timing. The use of actual engine torque data to estimate the generated torque from the amount of air and fuel in each combustion cycle was the unique feature of this study.

Since 1979, Nissan Motor Company's, Electronic Concentrated Engine Control System (ECCS) has been meeting various vehicle and engine needs. These needs include fuel economy, smooth operation, powerful acceleration, and a minimum of exhaust emmissions. The system has been regularly enhanced with the introduction of up-to-date sensors and actuators and improved control strategy and programs. This paper describes the various new control technology that has been added to the ECCS in recent years. It refers to the fail-safe or back-up system and self-diagnosis system, both of which have been very important for system reliability due to the increasing use of electronic control.

For purpose of clarifying the effect of quantity of lubricating oil supplied to the seal lip portion on sealing characteristics of oil seals, relations between the typical constructional applications of the fitting portion for oil seals and the quantity of the lubricating oil supplied to the oil seals are discussed. Then the necessary minimum quantity of the lubricating oil for preventing the seal lip from wear is investigated. And it is clarified that the decrease in sealing characteristics occurs when the lubricating oil is supplied insufficiently to the seal lip portion and, finally, the countermeasure is discussed.