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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.

The image processing technology using ITV cameras has been developed as a new type of sensor which can be used for many purposes. Especially, it is hopeful that the improvement of the traffic flow measuring system applying this technology can increase safety in tunnels on expressways. In this paper, we describe about the results of the development of this technology until present. And, the prospect in the future.

The Dynamic Navigation System is an information-providing type navigation and route guidance system. Fundamentally the system is suited for phased implementation. Some measures, however, must be taken in advance to enhance it to the advanced phase. For these measures, information providing data formats, travel time collection methods and small-delay system architecture have been studied. As a result, the flexible data composition for information provision, the on-board travel time measurement for efficient and accurate data collection and the autonomous communication network concept called ‘HYPO NET’ have been proposed.

With the rapid advances in electronic control within automobiles, the junction block (J/B), primarily used for electrical transmission and electrical wiring, has begun to house electronic control units. It is evolving into an active component with smart functions that also controls vehicle devices, at the core of the wiring harness. We have developed a method using CAE to predict the fatigue failure life of J/B brackets for use as a design-assist tool in the early stage of J/B development. Failure of J/B brackets starts with the repetitive stress generated in the brackets during resonance. This stress is maximum at primary natural vibration which is the lowest frequency during resonance. By accurately estimating the above-mentioned stresses using CAE, we established a method to determine the number of vibrations at which fatigue failure of the J/B bracket would occur (fatigue failure life) from the fatigue failure life characteristics of the material.

Through CAE (Computer Aided Engineering) analysis, a method in verifying the reliability of wire harnesses has been developed. The relative displacement of the engine causes the battery cable to bend repeatedly; this may result in cable breakage. By investigating the breakage mechanism of battery cables, we have found a correlation between the strain change and cable breakage. Furthermore, the dynamic profile through CAE analysis has been established, and it is also possible to calculate its strain. Using this method, we can limit the amount of actual tests and predict the bending life of battery cables.

Sumitomo Electric Industries (SEI), which has been producing its first generation ABS since 1987, has continued its R & D efforts to develop a second generation ABS better suited to a wider range of vehicles. A Compact ABS has been successfully developed, which has realized the smallest and lightest 3/4-channel hydraulic unit known to the authors, taking full advantage of the newly developed flow control valve.

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.

This paper describes an Automobile Navigation System with Multi-Source Guide Information. One of the features of this system is accurate location detection, which uses refined map-matching method incorporating a high accuracy rotation sensor, Fiber Optic Gyroscope (FOG). The system shows the position of the vehicle on a CRT map display and can also provide useful information, such as the locations of hotels, golf courses, etc., by using a CD-ROM disc. In addition to this information, this system can play CD-ROM discs based on the CDCRAFT standard. By means of this standard, software vendors can produce multimedia entertainment, such as a sightseeing guide with voice. Also, this system can display road and traffic information from the roadside radio beacons of the Vehicle Information & Communication System (VICS). This navigation system has been installed in Nissan's 1991 model Cedric, Gloria and CIMA.

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.

Fiber-optic data links have been developed for use in vehicle navigation systems, especially for the communication of CD data. The links consist of transmitters, receivers, and cable assemblies. The transmitters, which include only LEDs, must have driver circuits on their exteriors. In the receiver section, a PD, an amplifier, and a TTL compatible comparator are all integrated into the custom designed IC which is hermetically sealed into an originally developed metal package. Small optical connectors and heat-resistant plastic fiber cords with sufficient reliability and good operability for automotive uses have also been developed.

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.

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.

We developed a remote control unit (Hereinafter referred to as the controller) employing mainly an eight-directional joystick with push-button function. And it has good operational feeling. As previous joysticks generated operator feeling via springs, so the click sensation could not be felt. We thought that a good click feeling can be obtained by applying rubber contacts to the switch element of the joystick. Additionally, in order to include the push-button functions, we supported the operant unit with biaxial bearing and employed a sliding-knob structure penetrating this operant unit. Also in order to obtain a uniform operator feeling for all eight directions, we applied eight rubber contacts and gave the switches eight contacts. In order to restrain the rise in IC costs with the increase to eight contacts, we introduced an eight-contact four- output switch matrix and a one-contact three-electrode pattern.

Pollution is worsening in cities. The exhaust gas from vehicles is the main cause of air pollution in cities. The major drawback of the diesel engine is the Particulate Matter (PM) contained in the exhaust fumes which is also said to lead to cancer. For about 20 years many tests have been conducted in order to reduce PM in diesel exhaust gas. However the exhaust gas in present diesel engines contains a significant amount of PM. This is because there is no practical material for the Diesel Particulate Filter (DPF). Conventional ceramic materials have problems such as cracking and melting during regeneration and conventional metal materials lack adequate corrosion resistance for practical use. The authors present a new type of DPF made of metal porous matter (Celmet) which is designed with a thermal construction and simple control system in order to solve the problem of diesel exhaust gas.

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.

Recently, powder metal parts have been used in a lot of automobiles. One typical powder metal part is a helical gear. Compacting helical gears is much different from conventional compacting, because a part of the tool rotates on its own axis. The important points are as follows: (1) how to guide the upper punch into a die smoothly and to fit in it, (2) how to rotate the die/punch smoothly in order that the part of gear trains may not be broken by twisting stress during pressing process and (3) how to prevent green compacts from having crack/lamination. The larger the helix angle, the more difficult its compacting. The compacting of complicated shapes such as helical gears with an irregular shape or another helical gear is more difficult. Powder metal helical gears are produced because powder metal is suitable for mass production at low cost. Most powder metal helical gears are simple shapes such as helical gears only outside or inside.

We have developed a new type of system to prevent disc brake squealing. The rotor vibration radiates the squeal noise, therefore if the rotor vibration can be stopped electronically, no squeal is generated. Based on this concept, the Electronic Control Canceling System for a Disc Brake Noise ( ECCN ) was developed for the opposed type brake which has four brake pistons. The ECCN consists of four piezoelectric elements and one electronic control unit, and can stop the low-frequency squeal of 2∼4kHz by using a small amount of energy with the noise dynamometer and the test vehicle.

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.

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.

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.