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The first part of this paper describes air and gasoline heat-aging tests on various type 66 nylon resins. The results are pertinent for evaluating the suitability of these nylons for automotive applications such as the emission control canister and the gasoline vapor-liquid separator. In addition, data are presented to demonstrate that road salt caused no deterioration on test bars made from various 66, 610, and copolymer nylon resins which are in contact with galvanized zinc sheets in an acid environment. The second part of this paper discusses a survey which was made of a variety of automotive parts made of 66 nylon and acetal homopolymer to determine their quality after extended service. Parts, including body, chassis, engine, and transmission components, were removed from high mileage cars. Parts were evaluated for changes in dimension and strength. Their general condition was found to be excellent.

The quality of mixture formation and the combustion process is of significant importance for reducing the hydrocarbon emissions of small two stroke engines. The scope of this work was to investigate the mixture conditions after the exhaust closes and after the end of combustion depending on various engine operating points. For this experimental investigation a Gas Sampling Valve (GSV) was combined with a flame ionisation detector (FID) and a CO2-analyser. Using this technique, it was possible to measure the hydrocarbon concentration after end of combustion. Furthermore the local residual gas concentration after exhaust closes was determined. To allow for a comparison of the experimental results with calculations with CFD codes, in cylinder pressure measurement and exhaust gas measurements are done additionally.

In regard to small utility engines used in lawn and garden equipment and other commercial or industrial equipment, exhaust emission regulations have been implemented since 1995 in USA. In the State of California, USA, California Air Resources Board (CARB) Tier 2 emission regulations became effective from 2000. At this stage, the handheld engines are almost two-stroke engines, but this Tier 2 emission regulations are very stringent for HC emissions. In addition, the handheld engines are small, and so they do not have enough muffler volume to be equipped with larger catalysts. This paper describes the newly developed catalyst for two-stroke small engines, which is compact and excellent in HC conversion, to meet above requirements.

A numerical calculation method, which enables the analysis of gear train behavior including non-linear elements in a motorcycle engine, was established. During the modeling process, it was confirmed that factors such as bearing distortion, radial bearing clearance and elastic deformation of a tooth flank could not be neglected because they effect the rotation behavior. To keep a high accuracy, those factors were included in the simulation model, after they were converted into the rigidity elements along the rotational direction of each gear model. In addition, the model was combined with a crankshaft behavior calculation model for a driving and excitation source. A time domain numerical integration method was used to perform the transient response simulation across a wide range of engine speeds. A jump phenomenon of response behavior of the driven gear was predicted that is a characteristic of non-linear response. The phenomenon was also observed in a physical test.

This paper discusses the features and systems of a new compact skid steer loader. Special features of the new loader are a single member lift arm and worm gear wheel drives. The general systems of the machine will be discussed along with the special PTO option.

The MTS 329LT six degree-of-freedom road test simulator (6DOF RTS) provides additional controls for camber and steer moments resulting in more realistic simulation results compared with results for a 4DOF RTS. However, the 6DOF RTS requires that additional transducers be installed on the data acquisition vehicle to provide the road load information necessary to control these additional moments. Occasionally, road load data available for drive file development may not include the necessary information for controlling steer and camber moments (typically for 4DOF applications). Under such circumstances, it is still possible to develop drive files for solid-axle-type rear suspensions. A technique used to accomplish this task is presented in this paper.

With the intent of attend the Annex 10 performance specifications of the Economic Commission for Europe (ECE-R13), translated on NBR 14354/1999, it was necessary to develop a load sense valve installation layout also to the 6×4 vehicles. This work shows the steps for the development of the load sense valve installation and calibration on 6×4 vehicles, considering the valve performance on the two traction axles and preventing brake locking under low friction track conditions, under empty conditions use or with low load. The design required a detailed layout in order to develop a load sense valve attachment system considering the movement of both traction axles, as well as respecting the vehicle initial project physical limits; adjusting it to one of the available valve cams in the market; intending to develop a durable design and at the same time of low variable cost, with low tooling costs and that does not add much complexity to the production line.

This paper concerns an introduction on how to lead the 7 degrees of freedom (7DOF) model for understanding the vehicle-fluctuation during straight running. Despite the steering wheel being fixed at on-center by anchor rod connected to the floor, vehicle run with a very slow lateral fluctuation, of which amplitude is small but becomes maximum at a certain speed zone, was observed by a vehicle test on a flat road of the proving ground. For understanding this phenomenon, I provided the motion equation of the 7DOF model. By analysis using the motion equation, the existence of a speed zone where the amplitude becomes maximum is confirmed. This appears when the rear compliance steer is the proverse compliance steer and disappears by changing it to the adverse compliance steer. Where, the adverse/proverse compliance steer mean the characteristics of compliance steer that increase/decrease the side-slip angle versus the vector direction of the vehicle(1).

This paper presents the results of experiments conducted with a two-stroke engine that was the world's first such engine to comply with the emissions regulations applied to small off-road engines by the U.S. state of California in 2000. This engine is fitted with a scavenging passage that runs around the crankcase before the scavenging port. The aim of this research was to investigate how changes in the quantity of heat transferred to the fresh air as a result of varying the length of the scavenging passage would affect the state of combustion and exhaust gas composition. An ion probe was fitted to the end zone of the combustion chamber in order to detect the state of combustion. A voltage of 60 V was applied to the ion probe and measurements were made of the voltage drop that occurred due to the presence of high concentrations of ions (H3O+, C3H3+, CHO+, etc.) at the flame front.

The automotive industry continues to develop new powertrain technologies aimed at reducing overall vehicle level fuel consumption. The ongoing trends of “downsizing” and “down speeding” have led to the development of turbocharged engines with low displacement and high torque density. In order to meet the launch response requirements with these engines as well as fuel economy needs, transmissions with large ratio spreads will need to be developed. Due to the lack of torque amplification from the torque converter, the next generation of dual clutch transmissions (DCT) will need to have larger launch ratios and ratio spreads than currently available in production today. This paper discusses the development of a new family of DCT (called “xDCT”) for use in front wheel drive vehicles, aimed at meeting some of these challenges. The xDCT family features two innovative concepts, the idea of “gear generation” and “supported shifts”.

In designing new valve train system, it is useful to predict the complicated dynamic characteristics correctly by CAE simulation at the initial stage. In this paper, a modeling technique of mechanical system simulation and the simulation results about the dynamic characteristics of the diesel engine valve train are shown. From the measured results, it is found that the valve spring plays an important role in the dynamic characteristics of valve train. Based on the results, we propose a new model which use beam coupled the displacement and shearing stress and gap elements to express the valve spring. The model is proved very well to express not only the same-pitch valve spring but also the different-pitch valve spring. As a result, the prediction of the dynamic characteristics of the valve train provides a lot of effective data and hint for the developing valve train design of a newly designed diesel engine.

SIGNIFICANT REDUCTION IN THE TRANSPORTATION COST PER TON MILE OF BULK PRODUCTS IS ATTAINABLE BY THE PROPER ADAPTATION OF A TRUCK TRAIN TRANSPORT. IMPROVED HAUL ROADS, GREATER DISTANCES, AND INCREASED DEMAND FOR MINE PRODUCTS AT COMPETITIVE PRICES ARE RESULTING IN A RE-EVALUATION OF ALL COST ASPECTS OF MATERIAL MOVEMENT. THE TRUCK TRAIN CONCEPT USING RELATIVELY SMALLER TIRES THAN LARGE PIT TRUCKS OPENS THE DOOR TO REDUCED OPERATING COSTS BY LOWERING CYCLE TIMES AND COST PER MILE OF TIRES AND CAPITAL INVESTMENT.

A sequentially stratified scavenged engine is characterised by the principle that the cylinder is first scavenged by pure air, followed by the air/fuel mixture. The air is introduced into the upper part of the scavenging ducts through a piston port or a reed valve. To take full advantage of the stratified scavenged principle, the scavenging ducts have to be designed in a way, so that they can accommodate all the air that is delivered into the scavenging ducts. When converting a conventional two-stroke engine into a stratified scavenging engine, it is also important that the tuning and basic scavenging characteristics of the standard engine are not deteriorated. In this paper it is shown how these two aspects can be combined. Together with a theoretical approach for dimensioning the volume and length of the scavenging ducts, it gives a guideline on how to design the basic engine layout, for a stratified scavenged two-stroke engine.

Hayes Lemmerz has published papers (Ref 1 and 2 ) where different rotor designs were investigated to increase airflow velocity. We also have published the dynamometer test's data to show the 100 degrees F drop in temperature and 50% drop in deformation in rotors with 5% increase in airflow velocity (Ref 3). In the previous paper (Ref 4), the increase of 37.2% of airflow velocity in a 72 curved fin rotor design, was shown. In this paper, we are showing the results of dynamometer testing the 72 curved fin rotor design. When the 72 curve fin rotor design is compared to current production design, the 72 curve fin rotor design shows, a 140° F (60° C) drop in temperature during heating and cooling cycles. Hayes Lemmerz is testing this rotor design on standard vehicle tests ( LACT and DST). The results of these tests would be presented in another paper.

Hayes Lemmerz has pursued fin configurations in straight and curved fin rotors to achieve high airflow velocity. The largest increase in airflow velocity of 37.2% is achieved by curving fins to a specific entry and exit angle and increasing surface area by increasing fin number. There is a need for funneling air into the narrow entry in the hub area. The new “Hayes Air Director” successfully channels air into the curved fins. Hayes Lemmerz is in the process of casting rotors with curved fins and the air director idea. Dynamometer and vehicle tests will follow. The current renwood model of the rotor design shows 34.8 to 37.2% increase in airflow velocity when tested on the Hayes Airflow machine.

This paper presents some experimental and theoretical results of a low emission two-stroke cycle spark ignition engine for chainsaws, applied a stratified scavenging method to reduce Total Hydrocarbon (THC) emission caused by air/fuel mixture short-circuiting during the scavenging process. Stratified scavenging methods are applied reed valves to control air sucked into transfer ports for stratified scavenging during sucking process. The new chainsaw engine, however, is applied piston valves instead of the reed valves to keep the same size and to be simple structure as conventional Schnurle scavenging engine chainsaws. The piston has grooves built with both sides. The grooves connect an air inlet to transfer ports to suck air into the transfer ports during the sucking process. The new chainsaw, having the same power as conventional chainsaws, is reduced THC emission to about 1/3 of conventional one and can meet to EPA Phase II regulation on and after 2005 without catalyst.

Automotive pollutant emissions have been drastically restricted during the last ten years. These emission standards are now concerning small two-stroke engine. In order to reach future emission standard, it is essential to improve the scavenging flow, and especially the trapping efficiency of the engines. It is also interesting to have a tool for predicting the scavenging performances of an engine before the firing engine situation, which takes place late in the time scale of a development. A special test bench has been developed by D2T Group to visualize and quantify the scavenging process. It was also modelled with CFD tools, and a good correlation was observed between calculations and experimentations. This shows a good potential to reduce time and money spent in an engine development.

The 75 Ah actively cooled bipolar battery continues to undergo LEO life testing at 40% DOD and to date has completed 13,000 cycles. The EOC and EOD voltages indicate that there is slight degradation in the overall battery performance. The primary influence in this decline is considered to be one cell's poor performance. The potential for extended cycle life capability of bipolar batteries has been demonstrated. Ten 4-cell passively cooled bipolar batteries are on test at Space Systems/Loral (SS/L). Characterization testing has been completed. The results indicate that high capacity utilizations can be maintained at various discharge rates. Performance differences were noted and seem to be related to battery design variations. Further testing is planned.

In order to meet the new stringent emission limits for small handheld power tools technologies like methods to improve the scavenging process and after treatment devices are deployed. Additionally, professional machines such as chain saws add particular requirements to avoid mechanical failures. By precise control of the carburetion it is possible to yield the necessary reduction of the emission level yet to maintain the performance of the engine. Thus, the development of an Electronically Controlled Carburetion System to reduce the exhaust emissions of small IC engines for handheld power tools was initiated at the WHZ, Germany. Key requirements of such a system are: low cost, high reliability, low electrical power consumption, high accuracy in metering the fuel demand of the engine. First results are promising. A correlation between exhaust gas temperature and the fuel demand of the engine was confirmed for both, wide open throttle and part load operation.

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.