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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 response to global demands for environmental conservation, the automotive industry is placing greater focus on the development of fuel-efficient technologies to help reduce global CO2 emissions. With the aim of simultaneously improving fuel economy and driveability, TOYOTA has developed a new continuously variable transmission (CVT) vehicles in North America equipped with a 1.8-liter engine [1]. This new CVT features various technologies for improving fuel economy, including: the world's first coaxial 2-discharge port oil pump system, wider ratio coverage, a flex start system, low-viscosity CVT fluid, and a higher final gear ratio. This paper outlines the configuration, characteristics, performance, and new technologies of this CVT.

Countries and regions around the world are tightening emissions regulations in reaction to the increasing awareness of environmental conservation. At the same time, growing concerns about the depletion of raw materials as vehicle ownership continues to increase is prompting automakers to look for ways of decreasing the use of platinum-group metals (PGMs) in the exhaust systems. This research has developed a new catalyst with strong robustness against fluctuations in the exhaust gas and excellent nitrogen oxide (NOx) conversion performance. This catalyst incorporates rhodium (Rh) clusters with a particle size of several nanometers, and stabilized CeO2-ZrO2 solid-solution (CZ) with a pyrochlore crystal structure as a high-volume oxygen storage capacity (OSC) material with a slow O2 storage rate.

Toyota Motor Corporation has developed a new 6-speed automatic transmission (U660E) for the front-wheel drive vehicles and large displacement engines. The U660 E was adapted to achieve improved environmental protection, and meet safety standards, which are large concerns for the society and customer satisfaction, by being small, light, highly efficient, quick response, and high shift quality. Toyota fundamentally improved both the hardware and software of the control system to meet these important goals.

In the field of automobile disk wheels, demands for aluminum wheels have been increasing for the reason of ride comfort and better appearance. And over 90 percent of luxurious passenger cars are equipped with aluminum wheels. This trend is spurred also by the demand for higher fuel efficiency for the cause of environmental protection, which calls for weight reduction of automobiles. This paper reports our research on manufacturing light-weight, high-quality aluminum cast wheels; covering the entire process from basic design to casting, and placing emphasis on the following three points. 1) Determination of optimum wheel configuration through computer simulation 2) Selection of optimum material composition 3) Optimization of the thin plate casting conditions Combination of the above technologies developed for the purpose of weight reduction resulted in the weight reduction of approximately 20% over the conventional aluminum wheels.