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Researches and developments of electronic transmission control have been made along with the progresses of electronical technologies in order to meet the requirements of decreasing fuel consumption as well as improving drivability. And nowadays many kinds of electronically controlled transmissions have been applied to a variety of cars. In this paper, a history of electronic transmission control from the first control systems mounted on TOYOTA CORONA in 1970s for the first time in the world to the newest ones having a lock-up function for fluid coupling (Torque Converter) as well as progresses of the respective electronical transmissions to their practical uses will be explained.

Semi-active suspension is one of many effective devices to improve vehicle stability, controllability and riding comfort. A practical means to realize semi-active suspension is to vary the damping force of the shock absorber. In this paper, we propose a new type of shock absorber using a piezoelectric sensor and actuator. The piezoelectric sensor and actuator are built into the piston rod which is a part of the shock absorber. The piezoelectric element provides a fast response and a high actuation force. We used the piezoelectric element in shock absorbers in order to take advantage of these two features. High level compatibility between stability, controllability and riding comfort is expected, since damping force changes very quickly using this new type of shock absorber. In this paper, several topics are discussed. First, a general description of the damping force control system with simple configuration is explained.

As a part of a project to develop high performance, compact and lightweight vehicle radiators, a highly corrosion resistive fin has been developed, especially for use in the salt-laden environment. It is a thin plate with a mutual diffusion layer of Cu-Zn formed on either surface. Owing to this composite structure, not only the corrosion resistance is double that of Cu-Sn alloy fins that are currently in use with a thickness over 20% smaller than the latter (38 μm vs 50 μm), but the corrosion of the bonding solder has been reduced to one half because the Cu-Zn diffused layer has brought about substantial reduction in the fin's surface potential.

This paper introduces a new type of radiator that has been developed with the objective being, high performance (compact size), light weight, and high quality in the field of copper/brass radiators that are superior in heat conduction, lower in price, yet there is still more room for improvement. The development of a new copper/brass radiator with the objective being higher performance (more compact), lighter weight, and higher quality has been completed. The synthetic study covered is not only an in-depth analysis of performance and structure, but the new development of materials and production engineering. As a result, the new radiator has a minimum of 10% increased performance, a minimum of 25% weight reduction, and its corrosion resistance is more than twice that of a conventional radiator.

The new generation engines currently being developed tend to require cold type spark plugs, which are prone to fouling. This paper describes the development of a new Coil on Plug ignition system that resolves this problem by using the high energy and the fast secondary voltage rise time of a capacitive ignition while maintaining inductive ignition characteristics for good ignitability. To evaluate the effectiveness of the system, spark plug insulation resistance was monitored and cold tests were conducted. The results demonstrated that the new ignition system is remarkably effective: insulation resistance remains high and startability and driveability are unaffected under conditions normally leading to excessive misfires and failure to start with a conventional inductive system. To satisfy environmental concerns, automobile manufactures are increasingly turning to high compression ratio engines in view of their improved performance.

1 Attenuation of acoustic noise from automobile components is important for passenger comfort. Since the alternator is one of the major sources of noise, many manufacturers have studied the various mechanisms which generate noise within an alternator as well as the methods to reduce the noise level. This paper presents the dynamic properties of the alternator with respect to the acoustic noise during current generation, and introduces a vibration damping structure based on experimental modal analysis. Rotating magnetic forces in a magnetic circuit (stator and rotor) can excite numerous structural resonances, resulting in acoustic noise. A modal analysis performed on the major magnetic circuit of the alternator (Nippondenso Co., Ltd.) revealed that the stator has elliptic, triangular and rectangular mode shapes in the radial coordinate plane, while the rotor does not have any significant resonances in the same 0 - 3 kHz region.

The smaller and lighter SV-06 sliding vane type compressor has been developed as the successor of the swash plate type 10P08 compressor for mini-car air conditioning applications. The SV-06 is the first vane type compressor in the world which utilizes an aluminum cylinder and rotor to achieve weight reduction. This was accomplished by introducing several new features to the design, such as a boron treated vane and smooth cylinder profile. Thinner vanes and a high performance oil separator were also introduced for compactness. This paper presents the many design features that allow small size and low weight while maintaining compressor performance and reliability, and focuses on the most important technology: (1) Abrasion Characteristics of Boron Treated Vane Against Al-Si Alloy (2) Oil Separator Performance

Concerns on environmental protection are being intensified throughout the world in recent years. Of those concerns, depletion of the ozone layer in the atomosphere caused by CFC emission into the atomosphere is the target of serious concern as shown in Fig. 1. At present, the use of CFC production is restricted by regulations at the global level, and CFC will be phased out by the end of 1995. In this regard, the authors have developed a new vehicle air conditioner to adapt to a new refrigerant HFC-134a, which is gentle to the ozone layer, and to replace CFC-12. The new refrigerant system was introduced to the market in October, 1991, and the replacement will be almost completed by the end of 1993 for the Lexus and Toyota production vehicles. This paper describes the development of the new compressor lubricant, seal rubber, hose and desiccant by taking into consideration the materials concerned and the number of technological issues involved in the new refrigerant, HFC-134a.

In the diesel engine field, increasingly strict emission regulations and customer requirements have necessitated advanced technology. One important subject for diesel engines is cold startability and white smoke under cold conditions. In this paper, the combustion mechanism of a multi cylinder engine under cold conditions is discussed. First, during a starting condition, it is proved that the cold flame, which is caused by previously misfired fuel during intermittent combustion, promotes good combustion on the following cycle. Secondly, following engine starting, it is estimated that there is minimum fuel quantity above which combustion is carried out. The minimum fuel quantity depends upon the temperature of the combustion chamber. Unbalance between the minimum fuel quantity and actual injection quantity results in white smoke emission.

In recent years, designers have attributed increasing importance to reducing noise in car interiors, and various improvements have led to a steady decrease each year in said interior noise. More recently, there has been abundant research on quantitative and qualitative approaches to interior noise, including studies on improving sound quality, such as elimination of rumbling noise and creating a feeling of linearity. Particularly engine noise, one of the major causes of interior noise, has been studied from various angles and significantly reduced in recent years. This has led in turn to increased interest in air induction noise which was a relatively minor noise source in the past. One method of reducing induction noise is the addition of several resonators to the induction system. Induction system components, including resonators, have a major effect on engine output and fuel consumption.

In the diesel field, innovative technology development has been desired for fuel injection system from the points of severe emission reduction to meet increasingly stringent emission regulation year by year respecting environmental protection and product improvement for various customer requirements including fuel consumption improvement. We have been pursuing the ideal fuel injection system which is called “ECD-U2” to meet above expectations. “ECD-U2” is the injection system of highly pressurized fuel with optimum injection timing by using of the injector controlled by high speed response magnetic valve. This system also has the fuel injection pattern controllability in one injection ( injection rate ) as one of the greatest asset. This report focuses on the new injector structure development to achieve desirable injection rate shaping for diesel engine combustion.

To improve vihicle compartment comfort, there has been a great demand for the development of odor filters which reduce odors, especially external diesel exhaust odors. Therefore, in efficiently developing cabin air filter combining dust removal and deodorant functin, a quantitative formula which enables acquisition of the correlation between sensory evaluation values and instrumental analysis values of odors has been designed and verified. We developed a deodorizing filter that effectively deodorized with minimal use of deodorant, combined with a dust filter based on these figures, to develop a high-performance air conditioning cabin air filter.

In the fall of 1984, Toyota marketed a new engine control system through the use of a commercial single-chip microcomputer. Engine control functions have been optimally allocated between the system's hardware and software, and three new circuit modules have been developed for the calculation of basic injected fuel amount, and knock control, ignition control. This has resulted in a large scale reduction of the load on the system's microcomputer, which has made the use of commercially available microcomputers possible, thus cutting costs while at the same time increasing the functions and reliability of the system.

This paper describes the development of the two-dimensional semiconductor device simulator called DS2* and its application in automotive power MOSFET design. DS2 clarifies carrier motions in MOSFETs under various operating conditions and calculates the current characteristics in intense electric fields in order to evaluate the device breakdown. Simulation results with p channel power MOSFETs for automotive application indicate that on resistance is significantly dependent on device miniaturization and that device breakdown is caused by one of three mechanisms which are, avalanche from the surface layer, reach through arid punch through.

EMI suppresion capacitors and filters are common in automobile electronics today, but they are insufficient for heavy concentrations of wideband electromagnetic radiation. To resolve this problem, a highly-integrated Ceramic Absorber was developed to efficiently shield against frequencies from 1MHz to 1000MHz, which is mountable on the control circuit board easily, as it is the form of a flat plate strip line. This filter provides the signal line with an electromagnetic absorption effect through line transmission characteristics. Research into ceramic materials was required to determine the specific dielectric constants and frequency characteristics of ferroelectric ceramic materials. The development objective was material with optimum dielectric dispersion, as determined from research into energy absorption based on the Debye dielectric dispersion theory.

Performance optimization of small diesel engines is greatly owing to the matched improvements between combustion chamber and fuel injection system. Fuel injection characteristics are especially important to realize optimum engine performance in all speed range. In recent years, lower noise and white smoke reduction during cold temperature operation have been strongly required for agricultural and industrial application, which are the same technical trend as automotive's. As these two requirements are in the trade - off relationship from a combustive point of view, it is very complicated to realize both at the same time. Therefore, fuel injection characteristics are analyzed in detail for important factors such as injection pressure pattern, its behavior and injection timing so that the aimed optimum engine performance is obtained. This paper describes an optimization example of achieving simultaneous reduction of white smoke and noise by fuel injection characteristics' improvements.