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In emerging markets, Port Fuel Injection (PFI) technology retains a higher market share than Gasoline Direct Injection (GDI) technology. In these markets fuel quality remains a concern even despite an overall improvement in quality. Typical PFI engines are sensitive to fuel quality regardless of brand, engine architecture, or cylinder configuration. One of the well-known impacts of fuel quality on PFI engines is the formation of Intake Valve Deposits (IVD). These deposits steadily accumulate over time and can lead to a deterioration of engine performance. IVD formation mechanisms have been characterized in previous studies. However, no test is available on a state-of-the-art engine to study the impact of fuel components on IVD formation. Therefore, a proprietary engine test was developed to test several chemistries. Sixteen fuel blends were tested. The deposit formation mechanism has been studied and analysed.

Engine friction reduction is an effective means to improve fuel consumption. Fluid friction reduction of main bearing is examined for engine friction reduction in cold condition. As one of the examinations, it was focused on low temperature of lubricating oil in the early stage during engine cold start. In hydrodynamic lubrication, the oil film temperature is maintained by balance between heat generation and heat transfer. The heat generation is generated by shear of lubricating oil. The factors of the heat transfer, the following elements are considered as follows, A) The heat transfer to a crank shaft, B) The heat transfer to a bearing, C) The heat transfer by convection. If the heat generation is constant, oil film temperature is increased by reduction of heat transfer. It is considered that the reduction of oil leakage and reduction of the heat transfer by convection is equivalent.

The new 2GR-FKS / FXS engines were developed to achieve stringent fuel economy and emission targets and respond to recent innovations in the field. The major parts of the 2GR-FKS/FXS engines were re-designed based on the well-received dynamic performance and fuel economy aspects of the 2GR-FE engine. The aims of this development were as follows. 1 Best-in-class power performance 2 Environmental performance that maximizes thermal efficiency and complies with fuel economy and emission regulations in each country by a wide margin 3 Engine response typical of V6 engines through drastic weight reduction of moving parts To achieve these conflicting aims, the developed engines use a modified version of the D-4S fuel injection system, which enables selective use of direct and port injection, in addition to advanced technologies such as variable valve technology (VVT) with a mid-position lock system and an exhaust port cooling system.

The new Toyota FCV “Mirai” has reduced the weight, size, and cost of the high-pressure hydrogen storage system while improving fueling performance. The four 70 MPa tanks used on the 2008 Toyota FCHV-adv were reduced to two new larger diameter tanks. The laminated structure of the tanks was optimized to reduce weight, and a high-strength low-cost carbon fiber material was newly developed and adopted. The size of the high-pressure valve was reduced by improving its structure and a high-pressure sensor from a conventional vehicle was modified for use in a high-pressure hydrogen atmosphere. These innovations helped to improve the weight of the whole storage system by approximately 15% in comparison with Toyota FCHV-adv, while reducing the number of component parts by half and substantially reducing cost. The time required to fuel the FCV was greatly reduced by chilling the filling gas temperature at the hydrogen filling station to −40°C (as per SAE J2601).

Fuel efficiency improvement measures are focusing on both cold and hot conditions to help reduce CO2 emissions. Recent technological trends for improving fuel economy such as hybrid vehicles (HVs), engine start and stop systems, and variable valve systems feature expanded use of low-temperature engine operation regions. Under cold conditions (oil temperature: approximately 30°C), fuel consumption is roughly 20% greater than under hot conditions (80°C). The main cause of the increased friction under cold conditions is increased oil viscosity. This research used the motoring slipping method to measure the effect of an improved crankshaft bearing, which accounts for a high proportion of friction under cold conditions. First, the effect of clearance was investigated. Although increasing the clearance helped to decrease friction due to the oil wedge effect, greater oil leakage reduced the oil film temperature increase generated by the friction.

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.

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.

In recent years, a number of different Blind Spot Monitor (BSM) systems have become more and more popular in North American automotive market. The BSM system advises the driver of vehicles travelling in adjacent lanes when these vehicles are also in the driver's outside rearview mirror blind spots. Similarly, when the vehicle is backing up from a parking spot, cross-traffic vehicles can be in the driver's outside mirror blind spots. In this situation, the Rear Cross Traffic Alert (RCTA) system alerts the driver when the driver shifts the vehicle in the reverse gear and there are approaching cross-traffic vehicles. The benefits of RCTA system was presented by [1]. The RCTA alert studied in this paper is given by playing an audible sound and by flashing the outside mirror indicators. The RCTA and BSM systems share the same vehicle sensors and most of their vehicle components.

The hole diameter of injection nozzles in diesel engines has become smaller and the nozzle coking could potentially cause injection characteristics and emissions to deteriorate. In this research, engine tests with zinc-added fuels, deposit analyses, laboratory tests and numerical calculations were carried out to clarify the deposit formation mechanisms. In the initial phase of deposit formation, lower zinc carboxylate formed close to the nozzle hole outlet by reactions between zinc in the fuel and lower carboxylic acid in the combustion gas. In the subsequent growth phase, the main component changed to zinc carbonate close to nozzle hole inlet by reactions with CO₂ in the combustion gas. Metal components and combustion gases are essential elements in the composition of these deposits. One way of removing these deposits is to utilize cavitations inside the nozzle holes.

Oil film thickness is one of the most important issues for optimization of bearing design. A technique has been developed to measure oil film thickness by noting the change in capacitance between the shaft and a thin-film electrode of several micrometers thickness formed on the surface of a bearing. The authors applied this technique to the main journals of an automobile engine and measured the oil film thickness up to maximum speed and full load. The oil film thickness became thinner with increased engine load, and then turned thicker with increased engine speed.

In this study, it is purpose to make clear the effect of cavitation phenomenon on the spray atomization. In this report, the cavitation phenomenon inside the nozzle hole was visualized and the pressure measurements along the wall of the nozzle hole were carried out by use of 25-times enlarged acrylic nozzle. For the representatives of regular gasoline, single and two-component fuels were used as a test fuel. In addition, various cavitating flow patterns same as experimental conditions were simulated by use of Barotropic model incorporated in commercial code of Star-CD scheme, and compared with experimental results.

A new hybrid transmission has been developed for New compact class vehicles. The development of this transmission has been aimed at improving fuel economy and achieving the weight reduction and compact size. In order to achieve these goals, the gear train and motor have been newly designed and advanced technology applied. This paper describes the major features and performance of this transmission in detail.

Toyota has developed a new system, which uses integrated control of powertrain by PowerTrain Management (PTM), in order to improve driving comfort and reliability. This system is currently in use on Lexus's new LS460. This system is composed of 4 parts: a generation part, a mediating part, a modification part and a distribution part. In each part, processes are based on drive power and torque. In the generation part, requests from a programmed model driver, Driving Support Computer and Vehicle Dynamics Integrated Management (VDIM) are generated and expressed by drive power. In the mediating part, most suitable vehicle drive power was selected among the requests. In the modification part, the selected request is modified using a programmed powertrain model, which considers internal combustion engine condition and powertrain response and transmission's tolerance. In the distribution part, optimized engine torque and gear ratio are processed.

Toyota has developed the world's first 8-speed automatic transmission (AA80E) for RWD automobiles. The transmission will first be used in the all-new Lexus LS460. In addition, a novel control system has been developed to maximize the predictability, response, efficiency, and initial quality of the powertrain while utilizing the high number of gear steps.

The slit nozzle in the fuel injection valve for a direct injection spark ignition gasoline engine forms a thin, fan-shaped spray. The fan-shaped spray is characterized by high dispersion, comparatively high penetration, and fine atomization. This enables it to form a stable air-fuel mixture. However, further improvement of engine performance requires that the spray characteristics (particularly the level of atomization) be improved. Since the spray characteristics are strongly influenced by the fuel flow within the nozzle, it was clarified this effect by visual analyses of the fuel flow inside the nozzle using enlarged acrylic slit nozzles. The results demonstrated that vortices that are formed within the nozzle sac are continuously propagated in a periodic manner within the sac and that they influence the streamline of fuel flow from the sac to the slit.

Newly designed gears are subject to higher loads that demand a steel that is capable of greater pitting resistance. The application of shot peening to gears has been increasing to improve tooth root strength, but pitting resistance had not been necessarily high. This study examines the effect of alloying additions mainly on tempering resistance and the formation of a non-martensitic layer. The developed high Si-Mo type steel shows excellent pitting resistance, even in shot peened gears, as compared to that of conventional steels due to high tempering resistance and the thin, uniform non-martensitic layer. This new steel is of practical use in some multi-speed automatic transmission gears.

The authors developed a useful analysis method of the rotational-angle of gear under transient state using the Hilbert Transform because the conventional method was not available under the transient state. Here, under the transient state the gear revolution speed was changed from 600r/min to 2000r/min in 0.35 seconds. A key technology of this method was that Hilbert Transform method, which used to be applicable only for steady data was improved so that it could treat transient data. Hence, the following procedures were developed. 1. The rotation of gear-teeth was detected by a gap-sensor pair, which can cancel the measuring error due to fluctuation of gear shaft. 2. The frequency of such signals varied significantly by the gear-revolution speed. Transient gear-teeth detection signals obtained at a constant sampling rate were converted to almost-constant frequency signals over the data series axis using a trigger pulse obtained per gear revolution.

1 A new hybrid transmission (P310) has been developed for FWD 3-liter engine class sports utility vehicles. The development of this transmission has been aimed at improving power performance and fuel economy, achieving the world's top-level weight reduction and compact size, while maintaining high torque capacity. In order to achieve these goals, the gear train and motor have been newly designed, and advanced technology has been applied. Moreover, this hybrid transmission achieves seamless acceleration and quiet performance. This paper describes the major features and performance of this transmission in detail.

In recent years, there has been a growing need for excellent automobile safety. The number of vehicle with active safety systems such as ABS, Brake Assist and VSC (Vehicle Stability Control) is dramatically increasing. A current brake control systems tend to generate activating noise and uncomfortable brake pedal feeling, which they have to restrain its positive use during ordinary braking. To improve this point, a new brake control system has been developed. This paper introduces the configuration, functions and effects of the system. The new hydraulic modulator adopts a gear pump (trochoid pump) and linear solenoid valves. This allows the modulator to be controlled silently and smoothly. As a result, it becomes possible to apply hydraulic pressure in the normal operating range at any time and a high level of performance is realized. Several new benefits were added to the current control system.

A new, free-cutting steel, hereafter referred to as “non-lead-added free-cutting steel”, has been developed with the intention of replacing currently applied lead containing free cutting steel. The ultimate goal of this project is to provide a new lead-free steel grade that will contribute to the removal of environmentally harmful substances from automobile parts. In this project, we have targeted the development of a material that would demonstrate levels of machinability and other mechanical properties equivalent to those of the conventional free-cutting steel to which sulfur (S), lead (Pb) and calcium (Ca) or combinations, thereof have been added. The fine dispersion of sulfide, modified by adding Mg and Ca, is most effective in enhancing the chip breakability that would otherwise deteriorate due to the absence of lead. The practical application of the non-lead-added free-cutting steel has rendered the goal of total removal of lead from special steel products highly obtainable.