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This paper examines the turbulent past and uncertain future of improving vehicle occupant protection through NHTSA vehicle safety regulations and mandatory seat belt legislation. The paper analyzes the pros, cons, and controversies associated with automatic restraints and mandatory seat belt laws. It emphasizes the conflicting data, reports, and testimonies presented to the NHTSA prior to its July 11, 1984 ruling. Recommendations are also presented on how best to protect vehicle occupants through regulation and legislation.

A computer simulation model to predict the thermal responses of an on-highway heavy duty diesel truck in transient operation was used to study several important cooling system design and operating variables. The truck used in this study was an International Harvester COF-9670 cab-over-chassis vehicle equipped with a McCord radiator, Cummins NTC-350 diesel engine, Kysor fan-clutch and shutter system, aftercooler, and standard cab heater and cooling system components. Input data from several portions of a Columbus to Bloomington, Indiana route were used from the Vehicle Mission Simulation (VMS) program to determine engine and vehicle operating conditions for the computer simulation model. The thermostat-fan, thermostat-shutter-fan, and thermostat-winterfront-fan systems were studied.

A set of control functions have been investigated for a computer controlled diesel cooling system, using the vehicle engine cooling system code. Various engine operating conditions such as the engine load, engine speed, and ambient temperature are considered as the controlling variables in the control loops. The truck simulated in the study was an International Harvester COF-9670 cab over chassis heavy-duty vehicle equipped with a standard cab heater, a Cummins NTC-350 diesel engine with a McCord radiator and standard cooling system components and after-cooler. The vehicle also had a Kysor fan-clutch and shutter system. Comparison simulation tests between the conventional cooling system and the computer controlled cooling system using the Vehicle-Engine-Cooling Computer System model under different ambient and route conditions show that the computer controlled cooling system would offer the following benefits: 1.

Simple diagnostic techniques exist which allow verification/ diagnosis of gasoline fueled, piston engine oil consumption. Use of these techniques can improve customer satisfaction, allow first time correction of the discrepancy, and reduce repair time and cost.

The automotive industry faces severe challenges in meeting both legislated requirements and market-place forces of the 1980’s. Many of these challenges impact on topcoat finishing of appearance parts. The purpose of this paper is to identify these forces and to describe anticipated needs and changes in topcoat finishing in response to these forces. The impact of specific legislation and the approaches being used for resolution are discussed.

This paper highlights the results of a program to study the effects of truck aerodynamics, splash, and spray. The approach has involved state of the art review and assessment, analysis, laboratory tests, model scale wind tunnel experiments, full scale tests, cost effectiveness analysis, and field evaluations. This paper summarizes the latter activities. The emphasis has been on devices fixed to trucks which can modify the air flow properties around the truck and reduce the formation and propagation of splash and spray as experienced by adjacent motorists. Such devices have been conceptualized, developed as prototypes, and tested under full scale and over the road conditions.

In order to improve the reliability of seals for automotive application in practical use, it is considered that further basic investigations concerning sealing characteristics of seals are necessary. However, it has been found, from analyzing seals decided in the market as defective parts, that the troubles of seals in the market are mainly caused by both wrong handling for seals and the use under wrong operating condition which has not been expected by manufacturers of seals. Therefore, in order to improve the reliability of seals, it is important to investigate in detail troubles on functional characteristics of seals and their countermeasures. In this paper, on oil seals, O-rings, water pump seals and dust cover seals as seals for automotive application, the results of investigations are discussed.

Data on exhaust emissions were obtained from a group of 1970 model-year vehicles operating over a range of ambient temperatures. The work is providing a baseline against which current-production vehicles can be compared, thus enabling a more complete assessment of automotive emissions reduction achievements. The vehicle fleet represented the 1970 model-year nationwide mix. The 25 cars were tested at 25°, 50°, 75°, and 100° F over the Environmental Protection Agency urban Federal test procedure, highway fuel economy test, and New York City driving cycles. Both temperature and driving cycle were found to have significant effects on exhaust emissions. The conditions which yielded the greatest adverse effects on emissions were: 1) low temperature--urban driving cycle, and 2) high temperature--New York City driving cycle. The data also indicate that the use of air conditioners causes increased emission levels.

With the completion of nine RRIM prototype programs at Davidson, the feasibility of producing RRIM automotive body panels has been demonstrated. The advantages RRIM offers to the automotive industry are documented by data obtained in these programs and emphasized with anin depth case study of one part. A set of material and design guidelines are presented which will help to ensure successful realization of RRIM’s benefits.

The RIM (Reaction Injection Molding) processing of several amine-cured epoxy resin systems has been shown to give a family of high modulus, high strength moldings with short “in mold” times. The mechanical properties of the RIM thermosets obtained from six different epoxy resin formulations are discussed in detail and the performance properties of epoxies and other RIM materials are compared.

In diesel engines with combustion-optimised for fuel consumption or emissions, mechanically-induced noise tends to control the overall engine noise level with that due to piston slap being predominant. Previous studies, mainly experimental, have helped to clarify the mechanism of the piston slap phenomenon and have suggested methods of control. This paper presents the latest results of a theoretical analysis of the piston slap dynamics which yields predictions of some optimum piston design features for low piston slap-induced noise related to the estimated mechanical efficiency of the engine.

In order to meet governmental requirements for automotive fuel economy, light weight materials must replace conventional materials. Reinforced reaction injection molded (RRIM) polyurethanes are expected to play a major role in weight reduction. Variations which must be considered in producing RRIM include the machinery, resin matrix, reinforcing material, and processing effects. Suitable production equipment appears to have been developed. Milled glass fiber reinforced RIM appears ready to compete on a commercial basis with SMC and BMC for exterior automotive applications. RRIM parts are self-supporting in thin sections, have a coefficient of thermal expansion approaching that of steel, and have very low shrinkage rates.

As a follow up to earlier publications, this paper reports on recent work carried out in Europe, within CEC, in the field of high shear reology aimed at defining a simple method to measure viscosity as seen by the engine. Seven SAE 15W–50 calibration oils were tested in a large number of high shear viscometers, engine tests and rigs in order to determine if any correlation was possible. The work has shown that the low shear viscosity does not correlate with the behaviour of the oil in the engine and that the viscosity under high shear conditions is from 70 to 90% of the low shear viscosity. Correlation was found between high shear viscometers and power loss/oil-flow in engines. Further work on lower viscosity oils is underway.

This paper consists of the prepared discussions and author closures from the two SAE/ASTM viscosity related symposia held in 1979 (Part V). The first symposium was held in Detroit, Michigan as part of the February–March SAE Congress and Exposition meeting and the second symposium was held in Dearborn, Michigan during the June SAE Passenger Car Meeting. The eight papers presented in these two symposia (Part V) were bound into a booklet along with four papers from the February, 1980 SAE/ASTM Viscosity Symposium (Part VI) held during the SAE Congress and Exposition meeting. These discussions and author closures for Part V only provide a supplement to SAE SP-460 and ASTM STP-621-S4.

Development work has been carried out on a turbo charged direct injection diesel engine with methanol, ethanol and gasoline. Using additives to increase the cetane number, emulsion with diesel fuel, forced ignition with diesel injected prior to the alternative fuel, by a separate injection system and carburation are the methods which have been investigated. Spark ignited diesel has been studied and is commented on to complete the picture. The intention of the paper is to evaluate these methods.

A liquid-crystal display using the twisted nematic mode was developed for an automotive instrument panel. A low viscosity, quick response liquid crystal of wide nematic range (−30 to 85°C) was designed with the aid of the molecular theory for viscosity of liquid crystals. A liquid crystal less than 20 cp at 25°C with wide mesomorphic range (−30 to 85°C) was developed. A display with this material gave quick response, about one and one-half seconds at −30°C. For the most uniform response and widest viewing angle, a liquid crystal molecular alignment of low tilt angle was developed. A simple rubbing alignment technique was used which is compatible to glass sealing. A polarizer resistive to high temperature and high humidity was applied. The display can be operated with good performance and high reliability.

The paper traces from the introduction of the internal combustion engine the numerous attempts that have been made to understand the fundamental origins of noise. It relates the progress made from very early subjective assessments to the present day sophisticated experimental and theoretical analyses.

A general pupose LCD driver chip set employing a (2/3) multiplexing scheme is presented. Mask programmable options of either four (4) or (3) common backplanes are provided. A master/slave approach is employed to yield a more optimum system expansion of frontplanes. Temperature tracking of liquid crystal threshold shift can readily be implemented off chip. Internal clock timing can be generated by either an on board oscillator circuit or an external clock source.

Systematically reviewed are the fundamentals of Electronic Fuel Management (EFM). Included is a discussion of five EFM areas: 1) air sensing concepts 2) fuel metering concepts 3) fuel delivery to the cylinders 4) fuel preparation with the air 5) calculation hardware (ECM) Presented as a part of the air sensing section is a summary of the physical principles that may be applied to compressible fluid mass air flow rate measurement. Finally, an example of digital computer control of a timed speed density system is reviewed.

This paper provides information on theory and design methods used to tailor pneumatic spring rate and natural frequency. Equations utilized in the design procedure are presented, and the interaction of the important variables is discussed. The vital role of laboratory testing and validation is emphasized. Although the paper is restricted to pneumatic spring design, peripheral equipment such as leveling valves and auxiliary reservoirs are addressed