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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.

Sumitomo Electric Industries (SEI) has developed the “Variable Flow Valve” (= VFV), which is small, low cost, and suitable for the precise control of hydraulic systems. With the VFV, the hydraulic flow can be regulated continuously by controlling the electric current. The VFV is able to regulate the flow of low viscosity fluid: under high pressure; in the low flow range; smoothly, quietly, and with quick response. We are confident that the performance and reliability of the VFV allow it to be applied to vehicle brake systems, and also hopes to find applications to other hydraulic systems.

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.

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 1990, The Japanese National Police Agency (NPA) planned a nationwide two-year research project including field experiments, “Travel Time Estimation and Prediction” aimed at realizing a reliable method of providing travel time information to drivers (1)*. The project was conducted by the Japan Traffic Management Technology Association and three system manufacturers (Sumitomo Electric, OMRON and Matsushita Communication) collaborated on research and experimental work. Several methods of estimating and predicting travel time were developed and evaluated in three major cities (Tokyo, Yokohama and Osaka). Four models, Sandglass, Delay Time, Auto Regressive and Neural Network Models were developed and evaluated using detector and license plate reader information, and field survey data in the three major cities. The first year evaluation results are described here.

A diesel particulate filter (DPF) using porous metal for a filter, due to its high thermal conductivity, and a radiation heater for a regeneration device, due to its uniform distribution of temperature, has been developed. When high trapping efficiency is required, filter thickness should be increased. However, the thicker filter has a problem of low regeneration efficiency caused by the declination of temperature in the direction of thickness in the filter. In order to improve regeneration efficiency, a filter-heater structure which achieves uniform distribution of temperature was designed by using computer simulation and confirmed good regeneration efficiency of this structure in the experiment.

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.

The weight of wire harnesses increases with the growing number of systems used in the vehicle in recent years. For the purpose of reducing the weight of wire harnesses, aluminum instead of the conventional copper is getting popular as a wire conductor. The conventional Al wire, however, is not able to be used for small gauge wires such as the sizes of 0.35mm2 and 0.5mm2 and wires used in the engine compartment due to its insufficient conductor strength. For this reason, we tried to develop a stronger aluminum alloy that has conductor strength equivalent to or stronger than that of copper. For the first time in the industry, we have successfully developed a high-strength aluminum alloy wire. Starting with the application of 0.35mm2 wire for engine wire harnesses, we began mass production in April 2015. This paper reports the development of high-strength aluminum alloy that can be used for small gauge wires and wires used in the engine compartment.

From the viewpoint of reducing the environmental impacts by automobile emission, improving fuel efficiency is essential. That is why automobiles need to be lightened. However, more and more electrical systems have been necessary in an automobile to ensure safety and comfort. With the increase in the number of electrical systems, the weight of Electrical Distribution System (EDS) also has become increased. In order to reduce the weight of EDS, it was decided to evaluate a change of material from copper to aluminum. In fact, aluminum wires have been used for high-voltage wires, but they have almost never been used for low-voltage wires. SUMITOMO ELECTRIC GROUP developed an aluminum wire that is available for low-voltage wire harnesses and started mass production of the wire from October 2010. In this paper, I'm reporting mainly on our development of a new aluminum alloy that can be used for aluminum wires.

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.