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The new Jatco CVT8 High Torque (CVT8 HT) was developed for use on front-wheel-drive vehicles fitted with a large displacement engine. The development objectives set for this new CVT with a high torque capacity were outstanding fuel economy, size and weight reductions. To achieve those targets, a high torque capacity CVT chain was newly developed in cooperation with LuK GmbH & Co. KG. This article describes the efforts undertaken to develop increasing torque capacity.

It was found that pitting resistance of gears is strongly influenced by resistance to temper softening of carburized steel. The investigation about the influence of chemical compositions on hardness after tempering revealed that silicon, chromium and molybdenum are effective elements to improve resistance to temper softening and pitting resistance. Considering the production of gears, molybdenum is unfavorable because it increases hardness of normalized or annealed condition. Developed new steel contains about 0.5 mass% of silicon and 2.7 mass% chromium. The new steel has excellent pitting resistance and wear resistance. Fatigue and impact strength are equivalent to conventional carburized steels. Cold-formability and machinability of the new steel are adequate for manufacturing gears because of its ordinary hardness before carburizing. The new steel has already been put to practical use in automatic transmission gears. Application test results are also reported.

Two concepts of rocket based combined cycle for single stage rocket are examined. Concept of SSR power plant consisted of liquid rocket engine and liquid air cycle engine is proposed and substantiated. The advantage of LACE with mixed air+oxygen oxidizer over pure LACE is shown. This combination provides increase of payload fraction of SSR up to 2.7% of the vehicle initial mass compared to rocket with pure LRE. Performance and specific mass of the combined engine are determined. Optimal range of oxidizer/hydrogen mixture ratio is shown. Methods of liquefaction ratio increase are discussed. Second concept considers LRE cycle integration with atmospheric air separation system. The main feature of the scheme is that air separation system provides positive thrust at the initial acceleration. With the same assumption for mass estimation, the concept shows close results to LACE/LRE combination in terms of rocket payload fraction.

The application of both high strength gear steels and shot peening technology has succeeded in strengthening automotive transmission gears. This technology, though, improves mainly the fatigue strength at the tooth root, but not the pitting property at the tooth face. Therefore, demand has moved to the development of new gear steels with good pitting resistance. In order to improve pitting resistance, the authors studied super carburizing which is characterized by carbide dispersion in the case, especially processed with a plasma carburizing furnace. Firstly, the influence of the carburizing temperature and carburizing period on the carbide morphology was investigated and the optimum carburizing conditions were determined. Secondly, the fatigue strength and pitting resistance was evaluated using carbide dispersed specimens.

An electronic monitor for car use using a 5.9-inch diagonal full color TFT-LCD (Thin Film Transistor Liquid Crystal Display) has been newly developed and is now being manufactured. The LCD monitor has several merits when compared to a CRT (Cathode Ray Tube) monitor: reduced dimensions (especially in its depth), lighter weight and lower power consumption. This paper introduces the LCD monitor and the technologies developed for each of its element: the new LCD panel, the back light system, the signal processing circuit and the temperature compensation technology.

Kyocera silicon nitride SN220M has been developed for automotive applications. Its charactaristics have been well established and examined. This paper presents the static fatigue behavior, along with physical properties and a review of automotive applications of the SN220M. Also, high performance silicon nitride materials, SN251 for gas turbine and SN235 for automotive applications, are discussed for further increase of engine performance.