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The cutting and welding of lithium-ion battery for EV using the fiber laser will become an applied technology that steals the limelight, and it can provide both flexibility and quality of the battery manufacturing process suddenly all over the world. We report the newest technology for the processing property and some advantage with newly developed 3 kW fiber laser. In the welding experiment, the aluminum lid of t1.5 mm was evaluated in the case of A1050 and t0.5 mm by using the fiber laser of 1 kW and the quality in the surface and the cross section when the fillet was welded was evaluated. The welded condition was CW (Continuous Wave), 800W and 60 mm/s, was able to even up half the welding depth of about 0.7 mm of the lid side as long as the section photograph was observed, and was able to judge a chemical liquid to be good quality as a seam welding.

This paper reviews the development of the new four-stroke diesel engine oil standards, JASO DH-2 and DL-1 (JASO M335-05) for Japanese automotive diesel engines equipped with after treatment devices, e.g. Diesel Particulate Filter (DPF) to meet the new long-term emissions regulations. These standards have been introduced in Japan in April 2005. The standards prescribe the minimum performance for engine oils conforming to Japan-made four-stroke diesel engines with aftertreatment devices using low sulfur diesel fuel (less than or equal to 0.005 mass % sulfur). The engine test requirements for these new standards are basically the same as those of the JASO DH-1 automotive diesel engine oil standard (JASO M-355 2000) to meet engine oil performances with soot dispersancy (ASTM D 5967-99), piston detergency (JASO M336-98), thermal and oxidation stability (ASTM Seq. IIIE and IIIF), and anti-wear performance (JASO M354-99).

The preliminary design of the Japanese Experiment Module (JEM) has started in January 1990. As a result of the JEM configuration review activity which was focused on the development cost and schedule prior to getting into the preliminary design, a part of the JEM Environmental Control and Life Support System (ECLSS) functions was changed. This paper presents the JEM ECLS system baseline and the subsystem configuration at the start of the Phase C/D. Also the outline of the preliminary cabin air ventilation testing which started in March 1989 is described.

Two types of high pressure injection equipment, which can produce a pressure of 250MPa, have been developed. One is a hydraulic pressure intensified type, having a “GRADUAL RISE AND SHARP CUT” injection rate pattern. The other is a pressure accumulator type, having a “SQUARE” injection rate pattern. These equipments have been evaluated with a high pressure vessel for analyzing the effect of injection pressure and injection rate upon the characteristics of non-evaporating fuel spray. High speed photography, shadow photography, holography and image analysis techniques were used for these studies. It was found that the fuel injected under high pressure forms finer droplets and produces a leaner mixture. It was also found that several differences exist in the structure of fuel spray between the accumulator type and the pressure intensified type. The reasons for these differences are discussed herein.

Characteristics of diesel combustion with high pressure fuel injection were investigated, using a supercharged and charge air cooled single cylinder engine. Observation and analysis of combustion was performed using high speed schlieren photography at a definite low level NOx emission, while varying the parameters of both injection pressure and swirl ratio. Engine performance at a high injection pressure was evaluated in combination with shallow dish type combustion chamber and 8 hole nozzle. Two different intake ports (higher and lower swirl ratio) were used for the evaluation. Conventional injection system in combination with toroidal cavity and 4 hole nozzle was compared as a base line. It is generally said that quiescent combustion system is suitable for higher injection pressure configuration. According to the observed result of combustion photographs, however, higher swirl ratio shows better mixing than a lower swirl ratio, which was also confirmed by the performance test.

Direct and Schlieren Photographing of the combustion process in an actual D.I. diesel engine have been investigated, and by comparing both direct and schlieren methods with cylinder pressure measurement, the characteristics of mixing, ignition and burning process were analyzed. The different combustion characteristics induced by various in-cylinder air motions were also observed. The injected fuel spray jet pattern, which impinged on the combustion chamber wall, seems to affect the mixing process due to combination with in-cylinder air motion. The development of fuel jet spray was observed and compared with some theoretical treatments. The contribution of turbulence on combustion both in pre-mixed and diffusion type burning period was recognized and the effect of swirl especially on diffusion burning period was also confirmed.

The application of the P/M and P/F methods in the production of automotive parts was investigated and compared to the conventional methods of casting and forging, with special attention paid to the areas of cost and energy conservation. In relatively light parts weighing 200-500 grams, the use of P/M and P/F with pure iron powder resulted in a significant savings in both cost and energy consumption. In the heavier parts, however, this cost reduction was not realized because of the high cost for materials.