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It is important to reduce the viscosity of automatic transmission fluid (ATF) in order to improve fuel economy. However, in general, low viscosity fluid can cause metal fatigue, wear, and seizure. It is necessary to increase the viscosity of the fluid at higher temperatures to maintain the durability of the automatic transmission (AT). The key point is the selection of the base oil and the viscosity index improver (VII) with both a high viscosity index (VI) and excellent shear stability. On the basis of this concept, a new generation high performance ATF named WS was developed. WS can achieve the highest level of fuel economy, while maintaining the durability of the AT.

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.

In the field of automotive gasoline engines, new products aiming at greater fuel economy and cleaner exhaust gases are under development with the aim of preventing environmental destruction. Severe ignition environments such as lean combustion, stronger charge motion, and large quantities of EGR require ever greater combustion stability. In an effort to meet these requirements, an iridium plug has been developed that achieves high ignitability and long service life through reduction of its diameter, using a highly wear-resistant iridium alloy as the center electrode.(1)(2) Recently, direct injection engines have attracted attention. In stratified combustion, a feature of the direct injection engine, the introduction of rich air-fuel mixtures in the vicinity of the plug ignition region tends to cause carbon fouling. This necessitates plug carbon fouling resistance.

A new 3-way catalyst with NOx conversion performance for lean-burn engines has been developed. The catalyst oxidizes NOx and stores the resulting nitrate, which is then reduced by HC and CO during engine operation around the stoichiometric air/fuel ratio. Both the composition of the storage component and the particle sizes of the noble metal were optimized. In addition, a special air fuel mixture control has been developed to make the best of the NOx storage-reduction function. The present catalyst showed 90% conversion efficiency and improved fuel economy by 4% in the Japanese 10-15 mode test cycle. The efficiency remained at 60% or more after durability test.

In response to increasing demands for measures to conserve the global environment and the introduction of more stringent CO2 emissions regulations around the world, the automotive industry is placing greater focus on reducing levels of CO2 through the development of fuel-efficient technologies. With the aim of improving fuel economy, a new continuously variable transmission (CVT) has been developed for 2.0-liter class vehicles. This new CVT features various technologies for improving fuel economy including a coaxial 2-discharge port oil pump system, wider ratio coverage, low-viscosity CVT fluid, and a flex start system. This CVT is also compatible with a stop and start (S&S) system that reduces fuel consumption by shutting off the engine while the vehicle is stopped. In addition, the development of the CVT improves driveability by setting both the driving force and engine speed independently.

A description is made of new control methods to improve response of wheel slip regulation. These methods enabled a new Traction Control (TRC) system based on throttle control rather than brake pressure to be developed. Major points are as follows: (1) Use of fuel injection cut-off to minimize delay (2) Additional adaptive throttle control logic By these means, a response nearly equal to that with brake pressure control is achieved at lower cost and with a considerable weight saving. Furthermore, the system, by suppressing noise and vibration, enhances the driver's control ability.

In response to global demands for environmental conservation, the automotive industry is placing greater focus on the development of fuel-efficient technologies to help reduce global CO2 emissions. With the aim of simultaneously improving fuel economy and driveability, TOYOTA has developed a new continuously variable transmission (CVT) vehicles in North America equipped with a 1.8-liter engine [1]. This new CVT features various technologies for improving fuel economy, including: the world's first coaxial 2-discharge port oil pump system, wider ratio coverage, a flex start system, low-viscosity CVT fluid, and a higher final gear ratio. This paper outlines the configuration, characteristics, performance, and new technologies of this CVT.

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.

We developed a new Manual Transmission Gear Oil (MTF) named LV for improved fuel economy and CO2 reduction. MTF LV is a low viscosity fluid to reduce stir losses at lower temperatures. In general, low viscosity fluids can cause metal fatigue, wear and seizure. The MTF LV was designed to overcome these problems by maintaining the oil film thickness after it is deteriorated and improving the wear characteristics with additives. As a result, the MTF LV provides equal or better durability than the current MTF. In addition, it also has good performance at low temperatures, better shift feeling characteristics, and improved oxidation stability.

Toyota has developed a new sports shift control system introduced in the world's first eight-speed automatic transmission (AA80E), which is implemented in the “LS 460” and has been adopted in the “IS F” (upcoming 2008 model). This enables the IS F to be a vehicle that also permits the enjoyment of driving on circuits as well as achieving that “fun-to-drive” image. In sports driving, as achieved by the conventional torque converter-type automatic transmissions, shift response performance for shift operation and linearity performance for accelerator operations were challenges to tackle. On the contrary, the newly developed sports shift control system has resolved these challenges and enables the IS F to be capable of responding to a driver's intention quickly and accurately, letting the driver truly experience satisfaction.

Toyota Hybrid System (THS), the powertrain that combines a gasoline engine and an electric motor was first introduced in December 1997. It became the first mass-produced hybrid passenger vehicle in the world, gaining a reputation as a highly innovative vehicle, and its cumulative worldwide sales have exceeded 120,000 units. In 2003, THS had a further evolution. The “new-generation Toyota Hybrid System (THS II)” would be introduced on the new Prius. This report shall explain “THS II”, which achieved drastic improvements in power performance and fuel economy, while securing the most stringent emission standard Advanced Technology Partial Zero Emission Vehicle (ATPZEV).

Requirements to reduce emissions and improve vehicle fuel economy continue to increase, spurred on by agreements such as the Kyoto Protocol. Lubricants can play a role in improving fuel economy, as evidenced by the rise in the number of engine oil specifications worldwide that require fuel economy improvements. A novel friction modifier technology has been developed to further improve vehicle fuel economy. The development of this novel friction modifier technology which contains only N,O,C,H was previously published along with the initial demonstration of performance in motorized Toyota engines. In order to validate this performance in fired engine tests, oil was evaluated in a Toyota Corolla Fielder with a 1500 cc gasoline engine. Testing was conducted in the Japanese 10-15 and JC08 modes, as well as the European EC mode, and the US FTP mode.

High visibility electronic analog instruments with the blackface lens, lighting up pointers, and back lit dials are used in increasing number for automotive instrumentation. Now, we have developed a new instrument called Optical Space-Vision Instrumentation incorporating the above electronic analog instrument with virtual image by double reflection mechanism. The purpose of this development is to reduce reading time through far-focus and to improve visibility through high contrast. As part of this instrumentation, we also developed a new pointer that uses fluorescent material without a light-emitting element. This paper describes the construction and the engineering technology associated with this instrumentation. According to our test results, this instrument has realized a shorter reading time and higher contrast.

The camshaft for an automobile engine is generally made of chilled cast iron. Due to increasing demand for higher performance, lawer maintenance and better fuel economy, it is difficult to make the cast iron camshaft lighter and/or more durable. In order to overcome these problems, development of an integral camshaft comprised of a sintered alloy cam piece for better wear resistance and steel tube for weight saving has been accomplished. In 1981 Toyota Motor Corporation successively started the mass-production of the sintered intergral camshaft for the new 1.8 liter ls engine. The significant advantages are as follows; (1) Weight saving (2) Excellent wear resistance (3) Improvement of lubrication system (4) Saving machining cost

The EMT (Elastomer Modified Thermoplastics) currently used in passenger car bumper fascia are limited in retaining low CLTE (Coefficient of Linear Thermal Expansion) and impact resistance, although they are highly rigid, which allows a reduction in weight, and also have high flowability during injection molding. We have developed a new bumper material called “Super Olefin Polymer” using a unique theory based upon a reversal of the current concept. The current polymer design concept of the EMT material is to compound and disperse the EPR (Ethylene Propylene Rubber) into the resin matrix such as polypropylene. We reversed the domain and the matrix, and treated the resin phase as the filler and the elastomer phase as the matrix.

In order to meet requirements for lower fuel consumption, we have developed a technique for significantly decreasing valve train friction for a direct acting OHC engine. Droplets of pure titanium generated by the titanium nitride coating process of the shims improves the surface roughness of the cams, which eliminates the need to polish the cams. In an engine with these shims, the surface roughness of the cams is considerably improved within a few minutes of initial operation by the polishing action of the droplets. Valve train friction is greatly reduced by improving the surface roughness of the cams and shims, which results in better fuel economy.

The 1ZZ-FE engine is a newly developed in-line 4-cylinder, 1.8-liter, DOHC 4-valve engine mounted in the new Corolla. Abounding in new technologies including the laser-clad valve seat, high-pressure die-cast aluminum cylinder block, and the small-pitch chain drive DOHC, coupled with the fundamentally reviewed basic specifications, the new engine is compact and lightweight, offering high performance and good fuel economy. Anticipating even more stringent emission regulations in the future, in addition to the revision of the engine body, the layout of the exhaust system has been improved to enhance warm-up performance of the converter.

Toyota has been introducing several hybrid vehicles (HV) as a countermeasure to concerns related to the automotive mobility like CO2 reduction, energy security, and emission reduction in urban areas. A next step towards an even more effective solution for these concerns is a plug-in hybrid vehicle (PHV). This vehicle combines the advantages of electric vehicles (EV), which can use clean electric energy, and HV with it's high environmental potential and user-friendliness comparable to conventional vehicles such as a long cruising range. This paper describes a newly developed plug-in hybrid system and its vehicle performance. This system uses a Li-ion battery with high energy density and has an EV-range within usual trip length without sacrificing cabin space. The vehicle achieves a CO2 emission of 59g/km and meets the most stringent emission regulations in the world. The new PHV is a forerunner of the large-scale mass production PHV which will be introduced in a year.

Toyota has developed a new continuously variable transmission (CVT) named “Super CVT”. The Super CVT has a wide ratio coverage and adopts a newly developed integrated control system with a direct injection gasoline engine (D-4) equipped with electronically controlled throttle. The combined package has achieved good fuel economy and a high overall level of performance. This paper shows the major features and performance of the Super CVT.

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.