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Gas shielded metal arc welding is generally applied to automobile chassis parts. However, the weld parts with the E-coat show poor corrosion resistance. Therefore, the corrosion mechanism of the weld parts was investigated. The results found two reasons why the weld parts corroded faster than the non weld parts:(1)inadequate phosphating (2)defects in the E-coat. After detailed investigation, it was clarified that the major cause of poor corrosion resistance was the defects in the E-coat caused by slags formed on the surface of the weld bead. Therefore the amount of slag has to be decreased to improve the corrosion resistance. The effect of shielding gas composition on the amount of slag was then investigated. In the case of Ar and oxidizing gas mixture, the corrosion resistance improved as the oxidizing gas content decreased. This was due to the reduction of slags.

A model of a timing belt analyzed by FEM (a general non-linear finite element program:ABAQUS) successfully confirmed the mechanism that generates belt cord stress. Analysis revealed a good correlation between the experimental and computed results of stress distribution of the belt cord. Through calculation, it was discovered that belts broke near the tooth root, which is the point of maximum stress of the cord.

The main result of this paper is a real-time closed loop demonstration of spark advance control by interpretation of ionization current signals. The advantages of such a system is quantified. The ionization current, obtained by using the spark plug as a sensor, is rich on information, but the signal is also complex. A key step in our method is to use parameterized functions to describe the ionization current [1]. The results are validated on a SAAB 2.3 1, normally aspirated, production engine, showing that the placement of the pressure trace relative to TDC is controlled using only the ionization current for feedback.

Present corrosion testing procedures for brake fluids assess the properties of fresh fluids under some forms of environmental stress (e.g., water content, elevated temperature). These tests may not accurately predict corrosion protection properties of fluid after the years of continuous service typical of North American practice. This paper describes the development of laboratory accelerated aging procedures which reproduce the chemical changes occurring in brake fluids during long-term service. Short-duration vehicular tests with these lab-aged fluids have reproduced specific modes of corrosion previously observed only after long-term customer use.

This paper presents a system concept for detecting combustion misfire. The relevant research grew out of the more stringent requirements for On-Board Diagnostic systems (OBDII) mandated by the California Air Resources Board (CARB), effective as of model year 1997 onward. The system concept is based on evaluation of variations in crankshaft speed. Processes using engine roughness are applied in non-critical operating areas and/or on engines with a small number of cylinders. The modulation process is used in more critical areas. Research was done using a 12-cylinder engine and indicated the potential to comply with the California Air Resources Board's regulations for the model year (MY) 1997 and later.

The influence of variable air-fuel ratio inside a spark ignition engine is examined by the use of an ionization sensor. The measured ion currents are used for predicting the local air-fuel ratio in the vicinity of the spark plug. In order to support the results, a theoretical analysis has been made. An instationary chemical kinetic model burning a mixture of iso-octane and n-heptane is used for the calculations. The results are used to reconstruct the crank angle resolved ion current that has been measured in an engine. This technique has been developed in order to offer a supplementary low-cost facility of controlling the air-fuel ratio within the combustion chamber of an engine.

Wire bonding has become one of the primary methods of interconnection for automotive-electronic units. This includes: ignition modules, pressure sensors, voltage regulators, anti-lock braking modules, air-bag systems, distributoriess ignition modules, etc. As the technologies in the automotive field increases, both the wire bonders and the wire have to keep pace. One of the improvements over the past few years was the development of corrosion resistant wire used for automotive-electronic applications. Corrosion resistant wire is unique in that there are some essential dopants in the wire that prevent the wire from physical damage.

Results of experimental studies of the JDC (Jet Dispersion Combustion) method to stimulate burning in SI piston engines are presented. The principle of the method is to disperse combustion gases originated from the homogeneous charge flame kernel throughout whole combustion chamber by means of the gas jet introduced in the chamber from outside. Emphasis is placed on relationships between system parameters and pollutant emissions. Results of exhaust gas composition measurements are presented at various jet directions. In general, at any engine load, the external air injection tends to decrease CO and HC contents in the exhaust gas, and NOx concentration remains basically unchanged. At idling conditions, it was possible to decrease remarkably CO concentration (even below 0.2 % by volume) without increasing HC and NOx levels. The measured exhaust gas composition was strongly dependent on the injection direction.

This paper describes a thick film ZrO2 NOx sensor feasible for diesel and gasoline engine applications, and introduces modification items from the previous concept design.(1) The modification items comprise simplifying the sensing element design to reduce output terminals for package design and applying temperature control to the sensing element in order to minimize sensor performance dependency on gas temperature. The NOx sensor indicates a stable linear signal in proportion to NOx concentration in a wide range of temperature, A/F and NOx concentration as a practical condition on both gasoline and diesel engines. The NOx sensor shows a good response in hundred msec. and a sharp signal following NOx generation in a transient state as well. Besides, another type of a NOx sensor is proposed for low NOx measurement in a practical use, by an electromotive force(EMF) voltage instead of a pumping current.

The actuator is the essential part of the automatic control system of the diesel crankshaft rotation frequency. The actuator on base of the linear electromagnet is considered. The purpose of this paper is to determine the conditions of receiving minimum of the weight and to optimize the parameters of the actuator. The exact calculation of the leakage of the magnetic flux and the parameters of magnetic circuit allows to find the characterisctics of the actuator precisely. In order to investigate the magnetic field in the axi-simmetric and planar complex shaped bodies such a stator and rotor of the electrical machines we have to solve Maxwell equations in these bodies. In this paper we use the Finite element method to calculate the magnetic field because it makes possible to avoid the dificulties connected with the complex shape of the system. The results of this paper allows to choose the material, configuration and parameters of the actuator optimally.

An experimental study was performed, using cycle-resolved laser Doppler velocimetry (LDV) technique, to characterize the exhaust flow structure inside a catalytic converter retro-fitted to a firing four-cylinder gasoline engine over different operating conditions. A small fraction of titanium (IV) isopropoxide was dissolved in gasoline to generate titanium dioxide during combustion as seeding particles for LDV measurements. It was found that in the front plane of the catalytic monolith, the velocity is highly fluctuating due to the pulsating nature of the engine exhaust flow, which strongly depends on the engine operating conditions. Under unloaded condition, four pairs of major peaks are clearly observed in the time history of the velocity, which correspond to the main exhaust events of each individual cylinder.

A computer model has been developed to predict exhaust hydrocarbon emission levels from spark ignition engines. The model incorporates the two presently accepted main sources of unburned hydrocarbons: the top land piston-ring crevice and the oil film absorption/desorption process. The main innovation shown by the model is the consideration of the combustion period in the calculation of the unburned hydrocarbons concentration. Both the oil film and the crevice are divided into small volume elements. The flame position during combustion is monitored, so that it can be determined for each volume element if absorption or desorption in the oil film is taking place, and if the flow to the crevice is of burned or unburned mixture. The model shows that failure to consider the combustion event leads to an underestimation of about 18% of the HC desorbed from the oil film, and to an overestimation of around 14% of the HC released from the crevice.

Effective use of power integrated circuit packages in automotive systems requires thermal models. This paper provides detailed information on the transient and steady state characterization and modeling of power SOIC packages. Sixteen and twenty four pin wide body SOICs are analyzed in FR4 and polyimide systems. Model extraction, generation, and validation are presented. To validate the model, data taken in an electronic fuel injection system is analyzed and then compared to the simulation results. The model results show 3 % correlation to the actual data.

The five output switching power supply incorporates a switching supply, a protected switching supply slave, and three linear regulators. These regulators can supply automotive modules and sensors with all the voltage levels they need to operate. The system application is discussed showing the need for each of the outputs. Next the IC is described block by block, with detail given to the switching supply. System performance and application issues are also covered.

Particulate in the automotive emission gas is, whether the source of the engine is gasoline or diesel, a continuous target for the analysis because of its harmful feature to the environment, however, the actual measurement has been requiring various complicated procedures with lengthy time. The experiment is given by a measuring device which enables the direct measurement of a single particulate individually based on Helium Microwave Induced Plasma (MIP). This new device consists of three main parts: 1) the introducing section to induce a particulate on the filter as diffusing separately by He sonic velocity, 2) the exciting section with He plasma torch of high energy, and 3) the detecting section with 4 monochromators. Also, the automatic calibration function assures the accurate measurement, saving the manual calibration beforehand. The analyzer allows to measure the particles one by one. This consequence allows the high precision results with a fast, easy operation.

A fast response electromechanical sampling valve has been used to collect samples from the exhaust of a spark ignition engine. The variations in concentration of unburned fuel and other hydrocarbon species through the engine cycle have been analyzed by gas chromatography. The results have pointed out that most of the unburned fuel comes from sources located in the lower part of the combustion chamber, such as piston-ring crevices and oil film absorption/desorption. The appearance of non-fuel HC species in the exhaust have been related to the post-flame oxidation process of the unburned fuel. A high-frequency flame ionization detector (fast FID) was employed to measure the cyclic variation of the total exhaust hydrocarbons.

An exhaust air fuel ratio sensor (A/F sensor), which is applied to a 1997 model year LEV vehicle was developed. This sensor enables the detection of the exhaust gas air fuel ratio, both lean and rich of stoichiometric. This A/F sensor was developed from a lean mixture sensor, which has a proportional output to the exhaust gas air fuel ratio in the lean region only, by widening the detection range to rich air fuel ratios to 12:1. This sensor is comprised of a zirconia solid electrolyte and a platinum electrode with a ceramic coating used as a diffusion layer. As a result of improvements, it has a effective air fuel ratio range from 12 to 18 as required for LEV vehicles with model based air fuel control systems. It has a fast light off, -- within 20 seconds -- to minimize exhaust hydrocarbon content. Further, it has fast response times, less than 200 msec., to improve air fuel ratio controllability.

The primary goal of this research was to investigate the feasibility of measuring the oil film thickness in a journal bearing using an optical film thickness sensor earlier developed at Michigan Technological University. A bearing oil film thickness testing facility was designed to provide precise control of the sensor calibration and experimental measurements. The calibration of the sensor was achieved by the use of an in-bearing calibration setup that allowed manual changes of film thickness by moving the bearing sensor within the bearing. By varying the speed from 350 to 1100 RPM and the load from 0 to 55 kg in a journal bearing, the sensor was able to measure changes in oil film thickness from 0 to 25 μm. The trends caused by changing the load or speed were seen to be consistent with a mathematical model based on the two dimensional Reynolds equation for journal bearing design.

This paper reviews solid-state gas sensing techniques that could be developed to supersede the NDIR bench and the electrochemical cell that are presently used in the majority of aftermarket emission analysers. Techniques considered include acoustic wave devices, chemfets, chemi-resistors and optical devices. Technical performance, e.g. sensitivity, selectivity, stability and speed of response, are assessed and compared. Manufacturability, cost, interfacing and processing requirements are also examined. The capability for inclusion in a hand-held analyser unit is the key consideration. Techniques that meet the review criteria are identified and recommendations are made as to requirements for further research and development.

Investigation of operating parameters have been carried out for an FTIR system dedicated for emission analysis. Discussions are focused on the key parameters, such as spectral resolution, gas cell dimensions, quantification algorithm, and sample gas treatment. The spectral resolution has to be determined so that the scan rate is high enough to make transient analysis, the minimum detection limit is low enough to carry out high sensitivity measurement, and no cross sensitivity can be recognized. A trade-off relationship between the response and the sensitivity exists for the gas cell design. Small volume of the cell is desirable when gas replacement is considered. On the other hand, the sensitivity can be increased by enlarging the cell volume to obtain long optical path. Both quantification algorithm and the sample gas treatment have to be well arranged to obtain accurate concentration values of the gas compounds sampled from the tailpipe.