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In order to develop the valve rocker arm material for the new type engine, we investigated various materials whose chemical compositions were selected using 30% chromium cast iron, which had shown good results in screening evaluation tests, as the basis. High chromium cast irons are well known for their abrasive wear resistance, but it has been very difficult to apply them for use as rocker arm material because their machinability is very poor, and because it is difficult for them to have a regular microstructure. In this paper, both the manufacturing method for the rocker arm which decreases the disadvantages that high chromium cast iron have and the rocker arm material best suited for this method are described.

The automobile industry currently faces many challenges which may greatly impact on its foundry operations. One of these challenges, consumers'' demand for greater fuel efficiency, can be met by reducing the weight of castings used in automobiles, and minimizing engineering tolerances. In answer to this particular demand, engine foundries have begun to either produce cylinder blocks or other castings with aluminum rather than cast iron. However, if a reduction in weight (thin wall and near-net shaping) can be realized with cast iron, there would be numerous merits from the perspective of cost and compactness and there would be much more flexibility in automotive parts design.

This research developed a new measurement technology for thermal analysis of the heat radiation from a hybrid transaxle case surface to the air and improved the heat radiation performance. This heat flux measurement technology provides the method to measure heat flux without wiring of sensors. The method does not have effects of wiring on the temperature field and the flow field unlike the conventional methods. Therefore, multipoint measurement of heat flux on the case surface was enabled, and the distribution of heat flux was quantified. To measure heat flux, thermal resistances made of plastic plates were attached to the case surface and the infrared thermography was used for the temperature measurement. The preliminary examination was performed to confirm the accuracy of the thermal evaluation through heat flux measurement. The oil in the transaxle was heated and the amount of heat radiation from the case surface was measured.

This paper describes the application of a life prediction method for stainless steel exhaust manifolds. Examination of the exhaust manifold cracks indicated that many of the failures could be attributed to out-of-phase thermal fatigue due to compressive strains that occur at high temperatures. Therefore, the plastic strain range was used as the crack initiation criteria. In addition, the comparison of the calculated thermal fatigue stress-strain hysteresis to the experimental hysteresis made it clear that it was essential to use the stress-strain data that was obtained through tensile and compression testing by keeping the test specimens at the maximum temperature of the thermal fatigue test mode. A finite element crack prediction method was developed using the aforementioned material data and good results were obtained.

At the engine restart, when the temperature of the catalytic converter is low, additional fuel consumption would be required to warm up the catalyst for controlling exhaust emission.The aim of this study is to find a thermally optimal way to reduce fuel consumption for the catalyst warm up at the engine restart, by improving the thermal retention of the catalytic converter in the cool down process after the previous trip. To make analysis of the thermal flow around the catalytic converter, a 2-D thermal flow model was constructed using the thermal network method. This model simulates the following processes: 1) heat conduction between the substrate and the stainless steel case, 2) heat convection between the stainless steel case and the ambient air, 3) heat convection between the substrate and the gas inside the substrate, 4) heat generation due to chemical reactions.

This paper describes a new 2.4-liter 16-valve in-line four-cylinder engine, 2TZ-FE, which has been mounted horizontally on a new minivan, the TOYOTA PREVIA. This engine has the TOYOTA original compact 4-valve DOHC system (scissors gear mechanism), and TOYOTA's newest technologies, such as 75 deg. slant cylinder and Separated accessory Drive System. The compact configuration reduces the height of this engine to only 44Omm (17.3-inches). Engine location is under the flat floor on the midship rear-wheel-drive vehicle and allows the PREVIA to have a spacious cabin with walkthrough. Its high performance, 103kW at 500Orpm and 209Nm at 4000rpm, has been achieved through updated technologies, such as: Knock Controll System (KCS), well studied intake system and exhaust manifold which is made of stainless steel double pipe. At the same time, high reliability and quietness have been achieved for the 2TZ-FE by TOYOTA's updated technologies.

Roadway departure mitigation systems for helping to avoid and/or mitigate roadway departure collisions have been introduced by several vehicle manufactures in recent years. To support the development and performance evaluation of the roadway departure mitigation systems, a set of commonly seen roadside surrogate objects need to be developed. These objects include grass, curbs, metal guardrail, concrete divider, and traffic barrel/cones. This paper describes how to determine the representative color of these roadside surrogates. 24,762 locations with Google street view images were selected for the color determination of roadside objects. To mitigate the effect of the brightness to the color determination, the images not in good weather, not in bright daylight and under shade were manually eliminated. Then, the RGB values of the roadside objects in the remaining images were extracted.

Recently, use of aluminum engine parts has increased for fuel economy and power improvements. Aluminum cylinder heads, for example, are currently used in most engines. But, only low performance engine coolants are available for prevention of heat-transfer corrosion of aluminum cylinder heads. The authors have studied a laboratory test method that is able to accurately evaluate the performance of engine coolants for prevention of aluminum cylinder head corrosion. And we have developed the new test method by changing the test specimen temperature higher and the engine coolant temperature lower than the ASTM D4340 test. The new test has been confirmed engine bench test. We evaluated further the performance of many engine coolants of the world for prevention of aluminum cylinder head corrosion using the new test. We have known that there were a lot of poor performance engine coolants in the world.

The driving simulator (DS) developed by Toyota Motor Corporation simulates acceleration using translational (XY direction) and tilting motions. However, the driver of the DS may perceive a feeling of rotation generated by the tilting motion, which is not generated in an actual vehicle. If the driver perceives rotation, a vestibulo-ocular reflex (VOR) is generated that results in an unnecessary correction in the driver's gaze. This generates a conflict between the vestibular and visual sensations of the driver and causes motion sickness. Although such motion sickness can be alleviated by reducing the tilting motion of the DS, this has the effect of increasing the amount of XY motion, which has a limited range. Therefore, it is desirable to limit the reduction in the tilting motion of the DS to the specific timing and amount required to alleviate motion sickness. However, the timing and extent of the VOR has yet to be accurately identified.

This paper describes application of sintered silicon nitride to the swirl lower-chamber in order to improve performance of turbocharged diesel engines. Various stress analyses by finite element method and stress measurements have been applied to determine the design specifications for the component, which compromise brittleness of ceramic materials. Material development was conducted to evaluate strength, fracture toughness, and thermal properties for the sintered bodies. Ceramic injection molding has been employed to fabricate components with large quantities in the present work. Quality assurance for the components can be made by reliability evaluation methods as well as non-destructive and stress loading inspections. It is found that the engine performance with ceramic component has been increased in the power out put of 9PS as compared to that of conventional engines.

Plug-in hybrid vehicles (PHVs) and/or electric vehicles (EVs) as sustainable mobility rapidly penetrate into a new market. Cruising ranges of PHVs and EVs strongly depend on the energy density of batteries. In this paper, we briefly introduce our achievements of metal air batteries as one of the innovative batteries with high energy density.

It may be possible to simplify the structure and control systems of a lithium-ion battery by replacing the conventional liquid electrolyte with a solid electrolyte, resulting in higher energy density. However, power performance is a development issue of batteries using a solid electrolyte. To increase battery power performance, in addition to lithium ionic conductivity within the bulk of the electrolyte, it is also necessary to boost the lithium ionic conductivity at the interface between the electrode active material and the electrolyte, and to boost electron and lithium ionic conductivity within the cathode and anode active material. This research studied the mechanism of resistance reduction by electrode surface modification. Subsequently, this research attempted to improve electron conductivity by simultaneously introducing oxygen vacancies and carrying out nitrogen substitution in the crystalline structure of the Li4Ti5O12 anode active material.

Recently, Solid State Relay (SSR) using Power MOSFET or Intelligent Power Switch (IPS) has been increasingly used in automobile industries. Comparing with the mechanical relay, SSR offers relatively higher switching speed and reliability by its non-contact structure and self-protection function. Because of these outstanding features, SSR is often used in engine and safety control systems. A new SSR system for rear lamp control, which can offer higher levels of power line protection against overcurrent than conventional fuses. The SSR system has been developed utilizing Power MOSFET with a built-in overheat protection circuit (PW-MOS), high precision Current Sensing Resistor and newly developed Driver IC. The system functions and verification results on major issues are described as well as the future goals of such SSRs.

We have taken notice of Zn-Fe alloy electroplating with an eye to developing new corrosion-resistant steel sheets for automotive use with both cosmetic corrosion resistance and perforating corrosion resistance, and as a result of investigations into its paintability and corrosion resistance over the whole range of its compositions, we have come to a conclusion that steel sheets with two-layer Zn-Fe alloy electroplating that consists of a thin upper layer with a 75 to 85% Fe content and a lower layer with a 10 to 20% Fe content is the best choice.

This paper describes an outline of the Toyota FCHV-adv, a fuel cell vehicle with a practical cruising range of more than 500 km. The cold startability of the FCHV-adv was improved by modifying the FC stack and control system. As a result, the FCHV-adv is capable of starting at a temperature of -30°C. In the future, Toyota intends to improve durability and reduce costs and is continuing to cooperate with governments and energy businesses to establish infrastructure and make the necessary modifications to laws and regulations.

A precise control system for a molten ferrous alloy temperature above 1700 K after the completion of induction melting has been developed in order to produce high quality casting parts for automobiles. In this system, the molten ferrous alloy temperature is measured just one time by a disposable thermocouple after the melting. The system predicts the temperature transition after the measurement using an original thermal model, and adjusts the supplied electric power to the furnace automatically according to the predicted temperature. Using this thermal model, the system has attained control deviations within ±5K under the following temperature controls, and contributed to the quality control of casting parts and the energy-saving during furnace operations. Casting temperature for a cast-steel of 1813 K in a 300 kg capacity high-frequency induction furnace on the “Toyota Vacuum Casting Process”.

Authors have developed an apparatus which measures the piston temperature using electromagnetic induction. The characteristics of this apparatus are as follows; 1 Applicable to 6 points per cylinder and all cylinders 2 Capable of measuring while the engine is running from start to 6000r/min full-load operation 3 Wide measuring range; from -30 to 400 °C 4 High accuracy; ±2.5 °C 5 Quick and easy setup 6 High durability This technology contributes to realizing the best balance of piston reliability and matching of combustion conditions. In this report, authors analyzed its influences upon piston temperature when the ignition timing,the oil/water temperature or the oil flow from piston jet were changed, respectively.

This paper presents the numerical simulation method to predict the deactivation process of three-way catalytic converters. Three-way catalytic converter's deactivation typically results from thermal and chemical mechanisms. The major factor of thermal deactivation is the sintering of noble metal particles, which is known to depend on the ageing temperature and the oxygen concentration in the exhaust gas. The chemical deactivation is mainly caused by the poisoning, which has two effects on the catalyst deactivation. One effect is the loss of the catalyst activity, which is expressed by reduced frequency factors of reaction rates. Another effect is the suppression of the noble metal sintering. Poison deposits prevent the noble metal particles from moving in the washcoat, assisted by the reduced thermal loading of reaction heats, which is caused by the loss of the catalyst activity. Modeling these deactivation factors, we propose the rate expression of noble metal sintering.

This paper describes a new plastic coloring and forming system. The system greatly reduces the time and amount of raw materials necessary for color changes, and eliminates the need for manual cleaning during a color change. This system is well-suited for small-lot production with frequent color changes, as well as for automated production systems. The system is being used by auto parts makers, and is practical in a variety of other fields involved with the coloring and forming of plastics.

This paper describes the development of the electrical systems for the integrated control system which unified automobile electronic control systems and led to a dramatic improvement in vehicle dynamics. An outline of the system is presented first, followed by actual automobile application examples of electrical systems employing medium-speed multiplexing.