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Lean combustion has been well known to be an effective method to improve the thermal efficiency. However, leaner mixture is prone to cause the unstable combustion and poorer unburned hydrocarbon (UTHC) emissions. Pre-chamber turbulent jet combustion has been proved to enhance the combustion stability under ultra-lean conditions. However, more NOx is formed during the combustion, resulting in the fact that the tailpipe NOx emission is too high to be still not available for the real application. In this report, in order to achieve a higher air excess ratio while keeping lower UTHC emissions, and especially NOx emission, a new combustion technique which combined pre-chamber jet combustion with fuel reforming was proposed and experimentally demonstrated on a pre-chamber engine.

Toyota Motor Corporation has developed a new 2.0L Inline 4- Cylinder (I4) Gasoline Direct Injection Engine, the second Naturally Aspirated (NA) engine of the Toyota New Global Architecture (TNGA) engine series, to meet our customers’ expectations for drivability, performance, and fuel economy. The high speed combustion technologies adopted previously in our 2.5 L NA conventional and Hybrid Vehicle (HV) engines for the 2018 Toyota Camry are necessary for high engine power and thermal efficiency. To adopt our high speed combustion technology on engines with different displacements, the turbulence intensity has been defined as the target index of combustion speed. The basic engine structure has been revised by using Computational Fluid Dynamics (CFD) analysis to achieve the combustion target.

Since changes in market trends occur faster compared to the past and the market itself has become extremely diversified, the production line in plants needs to feature higher levels of flexibility and agility. To achieve goals, one possible option is the use of a single-spindle ultra-high-speed machine with a parallel link mechanism, which would substitute the conventional multi-spindle machine. Multi-spindle-type machinery has been widely used in aluminum component machining/transferring facilities, including, among others, those for cylinder blocks and cylinder heads. To ensure the required production line flexibility, it is necessary to modify the machinery to minimize the investment and lead time for new model production. This paper reports on the background, target and structure of parallel link-type machinery.

The mainstream solution in the machining line for aluminum engine components; i.e., cylinder blocks and cylinder heads, has been provided by a transfer line featuring a multi-spindle machining device. In spite of the advantages it can offer, the conventional system is found less appropriate for meeting recent demands. These demands are; minimized investment for adapting the system to new production, and enhanced flexibility to cope with more diversified manufacturing demands. A possible answer would be machinery that simultaneously achieves production efficiency similar to that of the multi- spindle machine and the flexibility of the NC machine. To achieve this goal, the "HVT-6000," an ultra-high-speed machining center featuring a tilt- positioning mechanism using direct drive (DD) motors, was developed.

Many projecting rod-type antennas, which stick to vehicles, are spoiling vehicle proportion and making wind shield noise. A flat and low-profile antenna, especially which can be conform to the vehicle body's contours. This paper proposes a new flat and low-profile antenna. The developed Band-Combining Flat (BCF) antenna is composed of multiple antenna elements, each characterized by high gain but narrow bandwidth. In order to realize TV reception, we have developed a band combining technology for the plural antenna elements. The characteristics of the BCF antenna are verified on a surface of an actual vehicle. The BCF antenna has performance for fine reception of TV broadcasting in VHF and UHF bands with high gain characteristic.

A new chemical process of forming a non-corrosive flux for aluminum brazing has been investigated. The flux is built up onto an aluminum surface in a layer form, which consists of K2AlF5·H2O or K2AlF5-H2O/Zn codeposition. The K2AlF5-H2O layer formed through a chemical reaction between the aluminum metal and an aqueous treating solution gives a good adherency to the substrate and acts as the flux for brazing. The codeposition flux has an advantage of eliminating a pre-zincplating for sacrificial corrosion, since a Zn diffusion layer is formed on the aluminum surface at the brazing process.