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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.

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.

Environmental improvement is moving forward, due in part to the reduction of fuel consumption of automatic transmission(AT) vehicles as a result of social requirements in recent years and many measures have been implemented. Adoption of idling stop is a typical example introduced to reduce energy consumption while the vehicle is stopped to improve the urban environment. However, there are problems such as responsiveness and smoothness for an AT vehicle when the engine is stopped with the shift selector in “D” range. To overcome these problems, a new start clutch control system has been developed using an electric oil pump installed in a simple hybrid vehicle called a mild hybrid. As a result, a smooth feeling starting performance is achieved by operating the system in combination with the engine and other systems.

Toyota Motor Corporation developed the Fuel Cell Hybrid Vehicle (FCHV). The FCHV-4 is an evolution of the conventional fuel cell vehicle that has made immense improvements in efficiency. Both a fuel cell and a secondary battery are used as sources of energy for the hybrid system. By using these energy sources proportionally, the system can be kept at or near its optimum state. The FCHV-4's system is designed to improve the efficiency and aims for high responsiveness when the vehicle is in a transitional state. In the same way as most electric vehicles, and as in the gasoline powered hybrid “Prius”, the energy the traction motor creates during breaking can be used to regenerate the secondary. The fuel cell and traction motor inverter are connected directly, with the secondary battery connected through the DC/DC converter to the fuel cell in parallel.

Development of a new battery system for Toyota Estima Hybrid, the world's first minivan hybrid vehicle, has been completed. The battery pack that consists of 30 nickel metal hydride battery modules is compactly arranged under the 3rd seat in the cabin along with components such as the battery cooling blower and the ducts. This arrangement was designed in consideration of user's vehicle use, passengers' comfort and efficient battery-cooling performance.

For the first time ever, a new hybrid system using a 42-V power supply system has been developed for better fuel economy, lower emissions and urban environment. This paper introduces the system configuration, features and gives actual vehicle evaluation results. This system has a motor generator (hereinafter abbreviated as M/G) connected to the engine crankshaft via a belt, in place of the alternator on a conventional vehicle. The electronic control of the M/G has five functions, 1 restarting the stopped engine, 2 driving the vehicle when starting, 3 driving auxiliaries when the engine is stopped, 4 power generation during ordinary traveling and 5 regenerative braking on deceleration braking. By restarting the engine via a belt with motor driving control, a smooth starting without discomfort is achieved. Furthermore, using this motor to drive auxiliaries during idle increases the number of idle stop opportunities.

ϵ-caprolactam was polymerized in the interlayer space of montmorillonite, the clay mineral yielding a nylon-clay hybrid (NCH). X-ray and TEM measurements revealed that each template of the silicate, which was 1 nm thick, was dispersed in the nylon 6 matrix, and that the interlayer distance of clay increased continuously from 1.2 nm for the unintercalated material to 21.4 nm for the intercalated material. Thus, NCH is a polymer-based molecular composite or a nano-composite. NCH contains 1-15 vol% of monolayer clay. Injection-molded NCH showed excellent mechanical properties compared with nylon 6 in terms of tensile strength, tensile modulus and heat resistance. The tensile modulus of NCH was twice that of Nylon 6, and the heat distortion temperature increased from 65°C for nylon 6 to 145°C for the NCH containing only 1.6 vol% of a clay mineral. It was found that such excellent properties of an NCH system was due to the strong ionic interaction between nylon 6 and the silicate layer.

The effect of GTL diesel fuel on organic materials used in fuel delivery systems of vehicles was investigated. Specimens made from 16 kinds of organic materials were immersed in GTL diesel fuels synthesized at Refinery-A and Refinery-B (referred to as GTL-A and GTL-B, respectively) and then subjected to tensile testing. The tensile test results revealed that elongation of the nylon sample immersed in GTL-A was extremely small, about 4% of that of untreated nylon. In the light of this finding, the GTL diesel fuels and nylons before and after immersion test were analyzed in detail using about 20 analysis methods to determine the cause for poor elongation. The following points were found. (1) GTL-A consisted of low molecular-weight paraffins. (2) GTL-A had low molecular-weight i-paraffins. (3) The nylon immersed in GTL-A contained low molecular-weight paraffins. (4) The paraffins in the nylon immersed in GTL-A were richer in i-paraffins than the original GTL-A.

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.

After the Great East Japan Earthquake on March 11, 2011, Toyota Motor Corporation received considerable public response regarding the role of vehicles in emergencies from a large number of customers. These included comments about the usefulness of the electricity supply system in the Estima Hybrid during the long power outages caused by the earthquake. In response, Toyota decided to install this system in its other hybrid electric vehicles (HEVs) and plug-in hybrid electric vehicles (PHEVs). This system is capable of supplying power up to 1,500 watts, which means that it can be used to operate virtually every household electrical device. Since the engine starts automatically when the main battery capacity is depleted, a single vehicle can supply the daily power needs of a normal house in Japan for about four days, providing that the battery is fully charged and the fuel tank is full.

In a previous paper (Part 1 of this series), nylon-66 specimens were immersed in two GTL diesel fuels (GTL-A and GTL-B) and then subjected to tensile testing. The tensile test results revealed that the elongation of the specimen immersed in GTL-A was dramatically reduced. The GTL diesel fuels and nylon specimens before and after immersion were analyzed to determine the cause of the decline in elongation. It was found that the poor elongation was caused by penetration and oxidation of low molecular-weight paraffins and that the ease of penetration and oxidation of paraffin depended on the structure of paraffin. In this paper, the low molecular-weight paraffins detected in GTL-A were mixed to produce model fuels. Then, pieces of nylon cut from the tensile test specimen, were immersed in the model fuels. In addition, partial oxidation products of the paraffin (alcohol, aldehyde or ketone and acid) were used in immersion tests of the nylon pieces.

In this paper, the authors have developed a new measuring method of the liquid fuel film thickness on walls, such as intake ports, the combustion chamber and cylinder liner of a Port Fuel Injection (PFI) engine, and clarified the fuel film behavior under various running conditions when Fiber-based Laser-Induced Fluorescence (Fiber-based LIF) was applied to the newly developed method. The thickness of the fuel film is measured by detecting the intensity of fluorescence from the film that is irradiated by a He-Cd laser. A single optical fiber is used to simultaneously transmit the laser beam and the fluorescence from the film. In addition, the S/N ratio of the fluorescence is improved by using a He-Cd laser of which the wavelength (λ=442nm) is able to efficiently irradiate test fuel doped 2-3-butandione. Using this method, the fuel film thickness on the wall of the PFI engine was analyzed in two case studies.

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.

The authors developed a high-reliability low-cost gold-plated connector for automobiles. The connector is covered with three plated layers, nickel, palladium-nickel alloy, and gold. The three-layer plating helps to reduce the required thickness of gold. This paper describes the reasons why palladium-nickel plating was adopted and compares the corrosion resistance, oxidation resistance and wear resistance of three-layer-plated materials with those of conventional gold-plated materials. In addition, the characterisitics of three-layer-plated connectors were compared with those of conventional gold-plated connectors. It was found that the reliability of three-layer-plated connectors was as high as that of conventional gold-plated connectors.

In the field of automotive body electronic control such as control of door locks, power windows, and wipers, there is a growing need of multiplexing communication to reduce the amount of wire harnesses. To meet this need, we developed a multiplexing communication protocol particularly suited to the body electronic control. Based on the developed protocol, we designed a communication control IC and a simple driver/receiver circuit with a few discrete components. The bus access method of the communication is the CSMA/CD with nondestructive bit arbitration, and its bit rate is 5 kbps. Its transmission media is a single wire. The communication IC has a multiplexing control block and a serial I/O block for an interface with a host CPU. It was fabricated using CMOS technology and has a chip of 2.6mm x 3.0mm in size that contains about 5,000 transistors. The driver/receiver circuit consists of one transistor, one capacitor and several resistors.

A high strength and high toughness new bainitic steel has been developed which shows comparable mechanical properties, fatigue property, and machinability to those of quenched and tempered SAE 5140. The heat treatment of the bainitic steel is aging after hot forging in order to improve ratio of 0.2% proof stress and tensile strength (i.e. yield ratio) and to avoid warpage associated with quenching. The new bainitic steel has been applied to the slender and lightweight lower arms for automotive suspension. As a result, the total production costs in the lower arms have been reduced by nearly 15 percent.

The new intelligent VVT (Variable Valve Timing) -i, is one of the systems developed to improve engine performance. The pulley unit is one of the most important mechanical components of the system. We developed a suitable process for the four main parts of the VVT-i pulley in order to achieve the target performance at a minimal cost. The requirements for the mechanical component, the pulley unit, include light weight and compact design as well as a quick response time. To satisfy these requirements, we developed three helical gears having unique profiles and high accuracy, and a timing pulley which must prevent pressurized oil from leaking. The inner gear is a helical gear with external teeth,and a key way on its inside diameter. The piston gear is a helical gear of which the inside and outside teeth have opposite helix angles. We developed a unique powder compacting technology for these two gears. The timing pulley is also made of sintered metal alloy.

This paper contains an explanation of a Multiplex Wiring System with Optical Data-Link for cars, which has been installed in the Toyota “Century” since 1982. In this system, a total of 64 signals related to door wiring are transmitted in a multiplex fashion, and the number of wires from the front right-hand door to the interior could be reduced from 46 wires, which were used with conventional wiring techniques, to 10 wires including 2 plastic optical fibers. This system also has various control functions which includes a door-lock control function. In order to give high reliability to this system, we have developed a new optical data-link as well as a new custom micro-computer. And in the automobile industry, such a large scale multiplex wiring system having high reliability is very innovative in our opinion and will surely have a large impact in the future.

A camshaft for an automobile engine is generally made of chilled cast iron. But, because of increased demand for higher performance engines, a camshaft with many camshaft has been expected. The cam intervals were necessarily narrow. So it was difficult to manufacture the conventional chilled cast iron camshaft at a moderate price. In the case of a rocker-arm type valve mechanism, higher wear resistance was necessary. After due consideration to solve these problems, development of surface remelted chilled layer camshafts by Toyota's unique manufacturing method has been accomplished. In 1984 Toyota Motor Corporation started the mass-production of this camshaft, first for the new 1.0 liter 1E engine, and then for the 1.3 liter 2E engine. In this paper, the excellent wear resistance, the low manufacturing cost and the characteristic manufacturing method are described.