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The wheel rotation sensor developed for navigation system is small and light, and generates high output voltage of 0.37V p-p without a prc-amplifier when the gap between the sensor and the multi-polarized magnetic rotor is 2.0mm. The sensor has excellent resistance to environmental conditions. Several simulation tests and car evaluations were carried out and it is confirmed that the sensor generates enough output voltage and satisfies requirements for the system including the decrease of output voltage caused by temperature, gap variation while running, and so on.

Recently, SiCr clean steel wire for springs on automotive engine valves has been developed. This report describes the characteristics of valve springs subjected to a new manufacturing process using SiCr clean steel wire. The process developed by the authors is as follows: First, form a helical spring with SiCr clean steel wire. Next, quench using the distortion preventing technic --Marquenching--. Temper at a temperature lower than the conventional temperature. Shot peen to the surface layer of the spring. And lastly, polish electrolytically to remove micro surface defects formed through shot peening. Using this new manufacturing process, a valve spring with high fatigue resistance can be produced. At the test stress of 588MPa(τm)±490MPa (τa), the number of cycles to fracture was above 100 million, while the number of cycles to fracture was 4 million using the conventional process with the SiCr clean steel which has the best fatigue resistance for commercial use.

We have developed new P/M Al-Si wrought alloys having high strength and high wear resistance for use in the rotors and vanes of rotary car air conditioners. In addition, combined with the development of near-net-shape extrusion technologies, through a joint project with Diesel Kiki Co.,Ltd., we have succeeded in the world's first mass production of rotors made of P/M aluminum wrought alloy. In this paper, the properties and production technology of vanes and rotors made with new P/M Al-Si wrought alloys are presented.

An internal gear-type pump has advantages compared with an external involute gear-type pump, for example, higher mechanical or volumetric efficiency, considerable reduction of weight and dimension in the oil-pump system[1]. This paper presents characteristics of the internal gear type rotors with a modified trochoidal profile in the oil-pump system, and new P/M(Powder Metallurgy) aluminum alloys which satisfy required wear properties as the lubrication oil-pump rotors. Also, the advantage of high volumetric efficiency and discharge performance and excellent properties of the oil-pump rotor with a modified trochoid profile were combined with a R/S (Rapidly Solidified) aluminum alloy in the scavenging pump for racing car engine. Good results without wear or damage after an actual race are also reported.

The joining process of silicon nitride (S13N4) turbine rotor and steel metal shaft was investigated. The process consists of brazing procedures with multi-layer metallizing and complementary steps involving shrink fitting and non-destructive tests. In the course of the brazing steps, preliminary investigations using small specimens were conducted on the formation of a highly strengthened interface at high temperature and thermal stress reduction, and superior high temperature strength and heat cycle resistance were obtained. Rotary tests at high temperature were successfully completed using the rotor joined by this process.

ABS sensor rings for automotive use are becoming smaller and thinner because of the demand for low cost and light weight. Such small thin parts are easier to break as they must withstand the same severe conditions as larger heavier parts. Superior elongation properties, after corrosion testing, are necessary for avoiding breakage and to obtain superior corrosion resistance. We have, therefore, developed such high performance P/M stainless steel with superior elongation and corrosion resistance. Conventional stainless steel has uniform pores on its inner surface which makes allows water penetration thus making corrosion worse and decreasing elongation. It is possible to increase corrosion resistance by changing pore structure (e.g. decrease continual pores) through the addition of special alloys that accelerate the sintering process.

We have developed a new Carbon/Carbon composite (C/C) manufacturing process called the “Carbon Powder Sintering Method [1] (C.P.S.M.)”. This study was conducted to evaluate the friction characteristics of C/C manufactured by the C.P.S.M. as compared with C/C manufactured by conventional methods using a dynamometer. In general, C/C shows a high friction coefficient at a high temperature, but shows a low friction coefficient at room temperature. There is a transition temperature point between both friction coefficients. As a result of this study, it was found that the transition temperature of the C.P.S.M. C/C is lower than for any other conventional C/C.

In the expansion of composite material application, it is one of the most important subjects in assembly of aircraft structure how drilling of composite/metal stack should be processed in an efficient way. This paper will show the result of development of a drill bit for CFRP/Aluminum-alloy stack by Kawasaki Heavy Industries (KHI) and Sumitomo Electric Hardmetal (SEH). In order to improve workability and economic performance, the drill bit which enables drilling CFRP/Al-alloy stack: at 1 shot; from both directions; without air blow and coolant (just usual vacuuming); was required. A best mix drill bit which has smooth multi angles edge and pointed finishing edge was produced as a result of some trials. Developed drill bit achieved required performance and contributed to large cost reduction, labor hour saving, production speed increase and work environment improvement.

Oil-pump rotors with a trochoidal tooth shape have many advantages compared with others, but the trochoidal tooth shape has not been sufficiently analyzed theoretically. So it is very difficult for the pump designer to decide the specifications for the trochoidal tooth shape, and it is also difficult for the supplier to meet the pump designer's requirements. We have been conducting theoretical analyses of trochoidal gears for several years, and have developed a system for designing the tooth shape. We can rapidly design the tooth shape, which meets the requirements of the pump designer, and develop the market for trochoidal gears by using this system. This paper shows the outline of the theoretical analysis, the outline of oil-pump rotors attached to crank shafts in automobiles as an example of the development of trochoidal gears, and some test results.

The high reliability silicon nitride sintered body and the mirror finish grinding machining technique have been developed, which improved fuel efficiency by reducing weight and friction loss of the valve systems. This ceramics, consists of finer grains (mean grain size:1-3μm) has high strength (σ 3b=1600MPa) and high Weibull modulus (m>20). In the case of motoring test by using this ceramics as the cam follower of the valve systems, it has a durability of more than 10,000rpm., which is approx. 30% higher than that of conventional silicone nitride, against the impact load to which the cam followers were subjected at occurrence of valve bouncing.

As the social aaareness of the need for greater automobile safety has risen, autonolive parts manufacturers have focused a lot of new research and development to aulomotive brake systems. Aith the much rapid advances and steady cost reductions in microelectronics technology, highly reliable, electronically controlled lour-thee1 antilock brake systems (ABS) are beginning to gain broad acceptance. Horever, wide acceptance of ABS depends upon the system and having superior performance, and high reliability at an affordable price. The toothed wheels (sensor rings) used for measuring the wheel velocity in the ABS require high precision in the pitch error of the teeth and specific magnetic properties in order to accurately detect wheel velocity, which is the first signal for brake control. Moreover, as these sensor rings are located close to the wheel, they require increased corrosion resistance ability higher than any other automotive parts.