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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.

Diamond-like carbon (DLC) coating has excellent properties like high hardness and low friction. So it has attracted considerable attention in recent years as a low-friction coating material. However, some DLC coatings display increased wear in oil containing Mo-DTC (Molybdenum-dithiocarbamates). Wear analyses of sliding surface after block-on-ring tests were conducted suggest that the decomposition product from Mo-DTC, MoO3, reacts with active sites in the DLC to promote the wear of DLC.

Display devices are required to have some fundamental functions which are brightness & gradation, colorfullness, resolution & sharpness, response time, and suitable size of the picture. Since the CRT (Cathode Ray Tube) is superior to the other display devices in these requirements, it can offer much information efficiently and effectively. Their visibility should not be evaluated only on the basis of some standards for office automation systems. From the point of view of human factors, visibility investigations of the CRTs for automobiles are examined. In this paper the relationship between the chromaticity difference and the luminance contrast for drivers to read the picture easily, and the luminance of the background in the CRTs for drivers not to be dazzled in the nighttime driving are clarified.

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.

TOYOTA has developed the world's first eight-speed automatic transmission (AA80E) for front-engine, rear-drive passenger cars. The AA80E developed for high-torque engines raises the level of power performance and fuel efficiency. To meet the size requirements needed for mounting in a passenger car application, an 8-speed geartrain, torque converter, transmission case and hydraulic control device were all newly-developed. Furthermore, the AA80E has benefited from technical developments to achieve an extremely high level of quietness and shifting performance. In this paper, the details of the AA80E are introduced.

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.

This paper describes an analysis of the rise in timing belt temperature occuring under high engine speed operation that was made to establish the cause of heat deterioration of the belt materials. Surface temperatures of the belt were accurately measured by correcting thermo-vision detected radiations to eliminate environmental radiation. The temperature profile of a belt cross-section was obtained by a specially developed thermo-couple device. The experimental results indicated that heat generated by the belt contributes significantly to the temperature rise and that the primary cause of the heat generation is bending hysteresis of the belt cords. In addition, a description is made of a method of calculating the rate of heat generation in the belt. In this simulation method, the energy dissipated as heat is calculated from the bending strains and loss moduli of the belt materials. Calculated results were found to agree well with experimental results.

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.

For a vehicle fatigue and strength testing system, two methods are usually used to accurately simulate the road-load on the test bench: one is the “separation of road-load into multi-axial loads” method and the other is the “compensation with frequency response function” method. These methods have remarkably improved the abnormality detection capability and accuracy of bench testing. For power steering or other units, however, the road-load points drift while the vehicle is driven. Further more, the road-load is applied in a complex manner to the vehicle. These factors make it difficult to separate the road-load into multi-axial loads and to provide stable measurement of the frequency response function. Thus, further progress of these methods has been delayed. The objective of this study was to make the bench testing of power steering units possible.

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.

Recently, the California Air Resources Board (CARB) has proposed a new set of evaporative emissions and “Useful Life” standards, called LEVII EVAP regulations, which are more stringent than those of the enhanced EVAP emissions regulations. If the new regulations are enforced, it will become increasingly important for the carbon canister to reduce Diurnal Breathing Loss (DBL) and to prevent deterioration of the canister. Therefore, careful studies have been made on the techniques to meet these regulations by clarifying the working capacity deterioration mechanism and the phenomenon of DBL in a carbon canister. It has been found that the deterioration of working capacity would occur if high boiling hydrocarbons, which are difficult to purge, fill up the micropores of the activated carbon, and Useful Life could be estimated more accurately according to the saturated adsorption mass of the activated carbon and the canister purge volume.

The human body undergoes a variety of changes as it ages through adulthood. These include both morphological (structural) changes (e.g., increased thoracic kyphosis) and material changes (e.g., osteoporosis). The purpose of this study is to evaluate structural changes that occur in the aging bony thorax and to assess the importance of these changes relative to the well-established material changes. The study involved two primary components. First, full-thorax computed tomography (CT) scans of 161 patients, age 18 to 89 years, were analyzed to quantify the angle of the ribs in the sagittal plane. A significant association between the angle of the ribs and age was identified, with the ribs becoming more perpendicular to the spine as age increased (0.08 degrees/year, p=0.012). Next, a finite element model of the thorax was used to evaluate the importance of this rib angle change relative to other factors associated with aging.

Pre-collision system (PCS) that basically consists of warning buzzer, brake-assist and automatic brake functions is designed to help mitigate injury occurring in frontal impacts where preceding vehicles are impacted from the rear. Since the benefit of each function is influenced by drivers' reaction before collision, it is difficult to estimate quantitative effectiveness for improvement. This paper proposes an approach to establish a Safety Impact Methodology (SIM) for the effectiveness estimation of a PCS by utilizing driving simulator (DS) test results and Event Data Recorder (EDR) data. The estimation procedure consists of four steps. Firstly, the PCS functions were modeled as linear transfer functions with gain, delay, etc. Test vehicle's properties were measured and modeled as an example. Secondly, the transfer functions were applied to each DS test result, and the speed reduction from travel speed to impact speed was calculated by the model assuming that PCS was installed.

The deterioration of the friction reducing properties of engine oils containing molybdenum dithiocarbamates (MoDTCs) in service was studied. A quantitative analysis of MoDTCs and zinc dithiophosphates (ZDTPs) remaining in aged oils revealed that ZDTPs were consumed faster than MoDTCs. The consumption rate of ZDTPs was slow in the presence of MoDTCs and peroxide-decomposing antioxidants. The frictional properties of aged oils were evaluated with a reciprocating friction tester (SRV tester). The friction coefficient measured with the SRV tester was correlated to the properties of the aged oils, such as the TAN increase, TBN, and concentration of remaining ZDTPs.

It may be possible to simplify the structure and control systems of a lithium-ion battery by replacing the conventional liquid electrolyte with a solid electrolyte, resulting in higher energy density. However, power performance is a development issue of batteries using a solid electrolyte. To increase battery power performance, in addition to lithium ionic conductivity within the bulk of the electrolyte, it is also necessary to boost the lithium ionic conductivity at the interface between the electrode active material and the electrolyte, and to boost electron and lithium ionic conductivity within the cathode and anode active material. This research studied the mechanism of resistance reduction by electrode surface modification. Subsequently, this research attempted to improve electron conductivity by simultaneously introducing oxygen vacancies and carrying out nitrogen substitution in the crystalline structure of the Li4Ti5O12 anode active material.

The use of brakes on public roads depends on traffic conditions and the road itself. In order to research into brake usage on various roads and under various conditions, a micro-computer data logging system was developed. The recorded data were analyzed by a large computer and the severity of brake usages was defined. The relationship between the severity and the brake disc rotor temperature was derived, and used to predict brake pad wear/life. The predicted wear coincided fairly clossly with measured wear.

The deactivation process of automotive catalysts by lead and phosphoruos were studied. The accelerated poisoning test were performed. The activity evaluation and characterisation of poisoned pellet oxidation catalysts showed the following origin of poisoning deactivations. Lead interacts with active materials and phosphorus covers over catalysts to reduce these catalytic performance. In the case of phosphorus and lead co-existence, the activity decreases rapidly because leadphosphate plugges pores of the support. In monolithic catalysts, highly axial distributions of poisons was obserbed. This characteristic distribution is advantageous for the durability of the catalyst.

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.

With the progress of super computers in recent years, a number of studies on “Computational Fluid Dynamics” (CFD) have been carried out, and various schemes for Navier-Stokes equations have been presented. Similar methods have also been applied to automotive engineering - aerodynamics, for exampre - in order to determine flow phenomena. In this paper, the application of numerical simulations to the flow cavitation that occurs in some part of orifices in the vehicle hydraulic system, will be discussed. Authors have developed a CFD program for the clarification of flow phenomena in such orifices. Using the relationship between calculated results and measured results of noise levels in such orifices, a new method for estimation of the occurrence of flow cavitation has also been developed. As a result, a new orifice configuration capable of preventing the cavitation has been designed.