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The wear mechanisms of the methanol engine were studied using dynamometer tests. Formic acid from methanol combustion mixes with the lubricant oil and attacks the metal surfaces. The iso tacho prorissis method was successfully applied to analyze the formic acid content of the used oil. A large amount of condensed water is also formed by methanol combustion and accelerates the wear. Wear can be effectively reduced by shortening lubricant oil change intervals, by using a special oil and by durable surface treatment of engine parts.

In-wheel motors (IWM) will be a key technology that contributes to the popularization of electric vehicles. Combining electric drive with IWM enables both good vehicle dynamics and a roomy interior. In addition, the responsiveness of IWM is also capable of raising dynamic control performance to an even higher level. IWM enable vertical body motion control as well as direct yaw control, electric skid control, and traction control. This means that IWM can replace most control actuators used in a vehicle chassis. The most important technology for IWM is to enable the motor to coexist with the brake and the suspension arms inside the wheel. The IWM drive unit described in this paper can be installed with a front double wishbone suspension, the most difficult configuration.

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.

In recent years, many various energy sources have been investigated as replacements for traditional automotive fossil fuels to help reduce CO2 emissions, respond to instabilities in the supply of fossil fuels, and reduce emissions of air pollutants in urban areas. Toyota Motor Corporation considers the plug-in hybrid vehicle (PHV), which can efficiently use electricity supplied from infrastructure, to be the most practical current solution to these issues. For this reason, Toyota began sales of the Prius Plug-in Hybrid in 2012 in the U.S., Europe and Japan. This is the first PHV to be mass-produced by Toyota Motor Corporation. Prior to this, in December 2009, Toyota sold 650 PHVs through lease programs for validation testing in the U.S., Europe and Japan. Additional 30 PHVs were introduced in China in March 2011 for the same objective.

The SEA model of wind noise requires the quantification of both the acoustic as well as the turbulent flow contributions to the exterior pressure. The acoustic pressure is difficult to measure because it is usually much lower in amplitude than the turbulent pressure. However, the coupling of the acoustic pressure to the surface vibration is usually much stronger than the turbulent pressure, especially in the acoustic coincidence frequency range. The coupling is determined by the spatial matching between the pressure and the vibration which can be described by the wavenumber spectra. This paper uses measured vibration modes of a vehicle window to determine the coupling to both acoustic and turbulent pressure fields and compares these to the results from an SEA model. The interior acoustic intensity radiating from the window during road tests is also used to validate the results.

The design requirement for more efficient vehicle moves a compact car toward front wheel drive arrangement, which requires an entire redesign of its power train. Toyota, with systematic approach from its planning stage, has developed a new automatic transmission series including one 3-speed and two 4-speed transmissions. An extensive examination on gear train arrangements enabled the 3-speed light, compact and highly reliable under the arrangement of Simpson gear train, and freewheel shifts with one-way clutches at every shifting. Two different 4th gear packages with freewheel shift are combined with the 3-speed unit to provide the versatility for the 4-speed units in various installations. Besides, these transmissions feature lock-up clutch converter, oil pump of a new tooth profile and two different control systems: hydraulic and electro-hydraulic.

The third generation four valve lean combustion engine controlled by newly designed combustion pressure sensor has been developed. This combustion sensor composed of a metal diaphragm and a thin silicone layer formed on devitron piece detects the combustion pressure in the No.1 cylinder. Comparing with the lean mixture sensor equipped in the first and second generation lean combustion engine, the lean misfire limit was detected directly with this sensor, and the lean operation range was expanded, which realized lower fuel consumption and NOx emission. The output torque fluctuation was minimized by precisely compensating the fuel supplied to individual cylinder based on the crank angle sensor signal. Separated dual intake ports, one with the swirl control valve and the other with helical port shape was designed and a twin spray injection nozzle was equipped between those ports. The swirl ratio was lowered from 2.2 to 1.7.

A compact and high-performance five-speed automatic transmission(A350E) has been developed for passenger cars. The development of this transmission has been aimed at improvement in acceleration performance in the low and medium speed range and at smooth acceleration. A five-speed automatic transmission with a simple gear train has been completed by means of the industry's first modern control theory aided shifting technique.

Lean mixture operation and high transient response has been accomplished by the introduction of newly designed Central Injection (Ci) system. This paper describes the effects of Ci design variables on its performance. Lean mixture operation has been attained by optimizing the injection interval, injection timing and fuel spray angle in order to improve the cylinder to cylinder air-fuel ratio distribution. Both air-fuel distribution and transient engine response are affected by the fuel spray angle. Widening the fuel spray angle improves the air-fuel distribution but worsen the transient engine response. This inconsistency has been solved by off-setting the injector away from the center axis of the throttle body and optimizing the fuel spray angle.

To prevent global warming, further reductions in carbon dioxide are required. It is therefore important to promote the spread of electric vehicles powered by internal combustion engines and electric vehicles without internal combustion engines. As a result, emissions from hybrid electric vehicles equipped with internal combustion engines should be further reduced. Interest in catalytic reactions in an electric field with a higher catalytic activity compared to conventional catalysts has increased because this technology consumes less energy than other electrical heating devices. This study was therefore undertaken to apply a catalytic reaction in an electric field to an exhaust emission control. First, the original experimental equipment was built with a high voltage system used to conduct catalytic activity tests.

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.

The need for small personal mobility vehicles is growing as urbanization, the aging of society, traffic congestion, and parking become major issues, particularly in inner-city areas. The aging of society also means that more short trips within communities will be made. The i-REAL personal mobility vehicle is a next-generation single-passenger electric vehicle that enables the driver to move around town using a smaller amount of energy. This compact EV has three wheels: two front wheels driven by in-wheel motors and one rear wheel. According to the driver's needs, the i-REAL switches driving modes by changing its wheelbase. It can go slowly, allowing the driver to meet the eyes of passers-by when driving in parks, on sidewalks, or inside shopping malls. When on the road, it can lower its height and drive quickly like a bicycle or motorcycle. The body of the i-REAL leans automatically based on the speed and the turn angle to maintain the balance of the vehicle for any driver.

In order to reduce CO2, EV and Hybrid Vehicle (HV) are effective. Those type vehicles have different power train from conventional vehicle. Those new power trains drastically improve their efficiency from conventional vehicle with keeping same or superior power performance. On the other hand, those vehicles have the issue for thermal energy shortage during warming up process. The thermal energy is very large. The thermal energy seriously affect on the fuel economy for HV and the mileage for EV. In this paper, the power performance, the fuel economy and the effect of heat energy recovery from the exhaust gas are discussed for HV. For the power performance, the simulated acceleration time of 0-100km/h was 11.8sec and the measured vehicle time was 11.9sec. The error between simulation and actual measurement result was 1.2%. As for the fuel economy, the energy management using exhaust gas heat exchange system improved 10.3% of the fuel consumption during warming up.

We have developed the world's first 8-speed automatic transmission for transverse FWD/4WD vehicles. The aim of this new automatic transmission was to achieve world-class fuel economy while offering both smooth gear shift and sporty shift feeling suitable for luxury cars. This has been accomplished using wide spread gear ratio, outstanding low drag components and highly efficient hydraulic control system. In addition, we have achieved the compactness similar to current 6-speed automatic transmission by adopting new gear train and compact clutch layout. In this paper, the detail of this automatic transmission is introduced.

Vehicles have been more required to save energy against the background of the tendency of ecology. As the result of improving efficiency of internal combustion engines and adoption of electric power train, heat loss from engine coolant, which is used to heat the cabin, decreases and consequently additional energy may be consumed to maintain thermal comfort in the passenger compartment in winter. This paper is concerned with the humidity control system that realizes reduction of ventilation heat loss by controlling recirculation rate of the HVAC system by using highly accurate humidity sensor to evaluate risk of fogging on the windshield. As the results of the control, fuel consumption of hybrid vehicles decreases and maximum range of electric vehicles increases.

Our L2-automated driving system enabling a driver to take his/her hands off from the steering wheel is self-operating on a highway, allowing the vehicle to automatically change lanes and overtake slow-speed leading vehicles. It includes an OTA function, which can extend the ODD after the market launch. To realize these features in reasonably safer and more reliable ways, system architecture must be designed well under hardware and software implementation constraints. One such major constraint is the system must be designed to make the most out of the existing sensor configuration on the vehicle, where five peripheral radars and a front camera for ADAS as well as panoramic-view and rear-view cameras for monitoring are available. In addition, four LiDARs and a telephoto camera are newly adopted for ADS. Another constraint is the system must consist of reliable redundant components for fail-safe operation.

A new automotive interior component material, TSOP-5 has been developed by refining the technology utilized to develop TSOP-1, the high modulus and high flow material for bumper covers. This new interior component material has excellent molding capability (MI=30dg/min.) yet still maintains high impact resistance which enables the material to be used in areas such as the dash board as well as trim covers requiring to meet the FMVSS 214, the new side impact regulation or the FMVSS 201, the new soft upper trim regulation.

The combustion chamber deposit (CCD) forming tendency of gasoline components and detergents were investigated with laboratory tests ad engine dynamometer tests. In the dynamometer tests, the driving conditions under which fuels and detergents influence CCD formation were specified, and the effects of different gasoline components and detergent blends on CCD formation were examined. In the laboratory tests, the CCD forming process was investigated thoroughly [10]. The CCD forming tendency of aromatic compounds in gasoline were dependent not only on physical properties such as molecular weight, but also chemical structure (number or position of the alkyl substituents of aromatic molecules). As for oxygenates, engine dynamometer tests with MTBE blended gasoline yielded less CCD than the test without MTBE. The CCD forming tendency of detergents correlated with the thermal decompositon tendency of the detergent package and the concentration of the main agents.

The change of the fuel flow rate in an injector with mileage accumulation causes poor drivability and exhaust emission deterioration in Otto-type methanol fueled vehicles with a multi-point fuel injection system. This is one of the serious problems which needs to be solved for the practical use of methanol fueled vehicles. The investigation results reveal that the wear of contact surfaces between a valve needle and a valve body increases the resistance force for valve needle movement and causes the change of dynamic fuel flow rate in the injector. The effects of several countermeasures to solve this problem are evaluated.