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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.

Automotive radar is one of the most important key technologies in sensors for Intelligent Transport Systems (ITS). It is considered very important to conduct analysis of the results which the radar took under various road conditions. In this paper, we shall report the results of a 76GHz automotive millimeter-wave radar using SS modulation technique, which were evaluated on roads under various situations. For example, multi-path was observed from the results that were analyzed from inside a tunnel. We believe that the results are very useful for development of the object discrimination algorithm.

Fuel efficient SAE 5W-20 automotive gasoline engine oils with molybdenum dithiocarbamates (MoDTCs) type friction modifiers were developed. The additive formulations were optimized with a motor-driven valve train friction test. The valve train friction was measured for both new oils and used oils, which had been prepared in a fired operation with bench engines, in order to evaluate the durability of the fuel efficiency. The combinations of MoDTCs, zinc dithiophosphates (ZnDTPs) and calcium salicylate type metallic detergents were found to be effective in reducing valve train friction and in improving its durability. From the results obtained, two oils, which had different ZnDTP formulations, were manufactured for evaluating field test performance. The SAE viscosity grade of the two oils was set at 5W-20 out of consideration of the reduction of hydrodynamic friction. Field test performance was evaluated with vehicles used for commuting in the Yokohama area.

A bench engine test for evaluating the fuel efficiency of automotive crankcase oils using modern engines was developed. The fuel consumption was primarily proportional to the viscosity of the oils down to 5 mm2/s at operating temperatures, indicating that the use of low-viscosity oil was effective in improving fuel efficiency. This may be because the oil film would be formed easily, since sliding parts, such as valve train systems, in modern engines are finely finished. Organo molybdenum dithiocarbamates were effective in improving fuel efficiency at high temperature. A 2.7% improvement in fuel efficiency relative to conventional SAE 10W-30 oils was achieved by the combination of low-viscosity SAE 5W-20 oils and organo molybdenum dithiocarbamates under constant operating conditions with engine speed 1,500 rpm and torque 37.2 N•m.

The effects of lubricant composition on low temperature wear were studied in low-to-medium temperature cyclic mode engine tests fueled with M-85. The wear characteristics on the cylinder bore, piston rings, bearings and cam lobes were dependent on the lubricant formulations, in particular the detergent chemistry. Calcium borate overbased detergents were found to be suitable for formulating methanol-capable automotive lubricants. Cylinder bore wear could be prevented by preserving the alkalinity of the lubricants during the tests. Valve train wear in M-85 engine tests was correlated with JASO motor-driven valve train wear tests using emulsified oils. The piston ring wear was at a similar level to that of gasoline fuels. Bearing wear was not significant and could be well correlated with the wear scar of the used oils measured with the four ball tests and was found to be of an abrasive nature.

Currently both the SAE and ISO are working on the standardization of distributed multiplex transmission protocols, and the Japanese Society of Automotive Engineers (JSAE) is in the process of evaluating the performance and reliability of a number of communication protocols with a view to contributing to this work of standardization.(1) This paper summarizes that aspect of the JSAE's communication protocol evaluation program that concerns response. CSMA /CD with non-destructive arbitration systems that are used in motor vehicles resemble ordinary CSMA/CD systems in that transmission delay times vary in accordance with traffic. Thus when there is a stringent need for response, it is essential to make judgments on the basis of the probability in terms of delay time. It is, however, impossible to determine delay probabilities experimentally due to the problem of the number of test runs, and this creates a need for methods using simulation and analysis.

A bench test was performed with Toyota 1500 cc OHC engines using a modified AMA mode in order to determine the change in performance, such as oxidation stability, thermal stability and antiwear performance, of gasoline engine oils as a consequence of their degradation. For the purpose of analyzing the relationship between the degradation of engine oils and their performance in detail, engine tests were performed without any new oil supply. The remaining performance of used oils was discussed in connection with both the degradation of engine oils and the depletion of oxidation inhibitors. The oxidation inhibitors, such as ZDTP, diarylamine and high molecular weight phenol, remaining in used oils were measured quantitatively with liquid chromatography. Oxidation stability, thermal stability and antiwear performance were measured with TFOUT, the hot tube test and the four ball test, respectively.

A new electronic controller for continuously varying the speed of windshield wiper motor has been developed. It permits conventional wiper motors without any modification to be set at any speed, low to high, for sophisticated wiper operation. Speed control is based on PWM and power MOS FETs. Fundamental problems peculiar to this method such as audible noise generation, R.F. noise generation, starting torque reduction, and speed drift due to load variation have been solved. Further, provided with the controller, the motor can keep its preset speed constant against changes in voltage, temperature, and torque. The controller, packaged in a small unit, is available at a low cost, and durable under severe automotive environment.