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A new process has been developed for the manufacture of passenger car wheels to reduce the effect of the wheel on vehicle shake. The process is now in production and the resulting improvements in uniformity are detailed here.

This paper describes a program conducted on a 1971 Continental Mark III to derive profiles of engine compartment temperatures for analysis of severe environment conditions to which primary wire would be subjected. Also covered are solutions to provide primary wire material selection, routing, and protective devices for specific problem areas.

Machining techniques that reduce the amplitude of low-speed radial uniformity measurements and their effects on smooth-road vehicle vibrations were investigated. The methods ranged from simple concentric and eccentric truing suited for service work to a servo-controlled tire-wheel assembly measuring and corrective machine installed at an auto assembly plant. These methods produce significant reduction of the measured low-speed radial uniformity. Corresponding vehicle evaluation showed significant reduction of smooth-road shake-a 1 per wheel revolution vibration-but little change of higher order vibrations. The simplicity of eccentric truing, combined with its predictable reduction of shake, provides a service fix for smooth-road shake.

Several new features have been developed for light-duty cranking motors which reduce costs, improve manufacturing productivity, and improve reliability. These include a face type commutator which combines the function of current collection and connection to the armature windings, fully insulated plastic molded brushgear, a single field coil to replace the four coils of a conventional four pole field system, a five roller extruded roller clutch, and a solenoid with a two part sintered iron body.

Irradiation of polymers by electrons or gamma rays effects cross-linking and increases high-temperature capabilities. Cross-linking does not, however, increase resistance to chemical degradation of a polymer. Changes in formulation can inhibit high-temperature oxidative degradation. The results of tests on the high-temperature stability of a series of polyvinylchloride formulations is presented, showing that changes in formulation accompanied by radiation cross-linking improve the ability of an insulation to function in high-temperature environments.

This paper introduces a design method, suitable for use on a computer, which predicts the performance of a cranking motor from the geometry of the machine and the material characteristics. The versatility of this method is illustrated by describing its use to produce optimum motor designs, to determine the effect of manufacturing and material specification tolerances, and to investigate marginal variations of component parameters in cranking systems.

This paper describes special winterization aids and petroleum products that have been developed to make possible the operation of automotive machinery, on an emergency basis, at temperatures as low as -70 F. A package of five basic petroleum products appropriate for use on the North Slope of Alaska has served there successfully for several years at temperatures consistently in the -40 F range. The products may be blended to obtain additional properties. The motor gasoline and diesel fuels developed for this package are discussed, along with the pour point and viscosity properties of Arctic winter lubricants-motor oils, ATF and torque fluids, hydraulic oils, gear oils, and greases.

We are currently faced with the possibility of operating millions of passenger cars and trucks on gasolines free of lead whereas they were designed to operate with leaded gasoline. The studies discussed in this paper illustrate the potential engine damage in the form of exhaust-valve seat wear that could result from such a move. This work shows that the inclusion of phosphorus in zero-lead gasoline is not a complete solution to the exhaust-valve seat wear problem, but that as little as 0.5 gm of lead per gallon in gasoline can provide complete exhaust-valve seat wear protection under relatively severe conditions of speed and load. Comparison of photomicrographs of exhaust valves and exhaust valve seats run with zero-lead and 0.5 gm leaded gasolines permits speculation on the mechanism responsible for exhaust valve seat wear in engines fueled with zero-lead gasoline.

Precombustion chamber engines are among the lowest emission power sources available today. Due to excellent fuel-air mixing and complete combustion, HC and CO emissions are extremely low. NO2 levels are also relatively low because of the divided chamber “quench effect.” Because of the low HC and CO levels, effort has been concentrated on lowering NO2 levels. Retarded timing, inlet air cooling, through the use of aftercoolers, water induction, and exhaust recirculation have all shown beneficial results. Smoke levels are minimized by selective matching of engine and turbocharger to assure adequate air for combustion.

The products of diesel combustion, including hydrocarbons, nitric oxide, carbon monoxide, and exhaust smoke are being controlled by current and future emission standards of federal and state governments. Fuel injection parameters, including tip design, injection timing, rate of injection, and the number and size of tip orifices were investigated with the unit injector, used in Detroit Diesel engines, for influence on these emissions. Results are presented to show control of hydrocarbon emissions by injector tip design. Reduction in nitric oxide emissions by changing injection parameters is limited by increased exhaust smoke and carbon monoxide and losses in fuel economy. Emission levels with the standard injector and an experimental injector, combining several injection parameter revisions, are compared with the 1973 California emission standards for diesel engines.

Individualism is still the prime factor in any system. All managers tend to drift into establishing routines that work best for themselves. Unfortunately, these routines may not be compatible with other office requirements. Information needs to be compiled for all levels of management to assist decision-making processes. Financial reporting to stockholders, lending institutions, and governmental agencies is also a must. Practicality, cost, and time available tend to be limiting factors in satisfying everyone's data needs. Variation in the figures shown in this paper can be used to assist managers responsible for one to any number of pieces of equipment in the day-to-day activities.

The increased industrial and commercial activities in the Arctic areas of the world have led to the development of special performance lubricants to meet these requirements. The technical requirements to meet the exigencies of commercial operation in the Arctic are discussed along with several lubricant approaches. The relative merits of the various types of lubricants including synthesized fluids, are presented together with the different areas of application.

The Twister testbed was operated on the Alaskan North Slope for three weeks in March and April 1970. Although the testbed configuration was somewhat removed from that required in terms of a “working” vehicle, it was believed that sufficient operating information could be obtained to develop an overall assessment of its potential. The trials indicated that Twister was capable of running over terrain typical to the North Slope at speeds three to five times faster than existing commercial vehicles. Twister's ride was substantially better when compared to existing vehicles. Although deep snow occasionally stopped the vehicle, the self-recovery capability permitted the accumulation of 800 miles of test operation, of which 500 miles were cross-country, without any need for assistance by another vehicle.

An electronic, fully automatic overload indicating system was developed and successfully applied to mobile construction type cranes. A mini-computer monitors the signals from boom load and boom angle transducers. It computes the resultant percentage of rated lifting capacity based on the crane's rating chart. A plug-in program card furnishes the safe operating limits from the rating chart.

A new concept of gear specification, called the “base pitch concept” is presented. This concept provides an explanation of and aids in understanding the functioning of involute gear teeth in action. It provides the gear designer with a system for interpretation and analysis of the results of information obtained from standard involute profile charts. A gear drawing specification which eliminates unnecessary information is presented.

The advantages of using the scanning electron microscope (SEM) to characterize automotive particles are described. The sample, collected using an Andersen sampler, is bombarded with electrons and the resultant x-rays are analyzed with an energy dispersive spectrometer. After many particles were observed, classifications were made for individual particles of one structural type greater than 3 μ in size; agglomerates, single masses of particles less than 1 μ; fines, particles of 500-1000 Å; and atypical particles. It is felt that with the advances in methods and technology this procedure will provide a strong basis for future sampling characterization and identification.

Hierarchical computer systems are an effective way of combining the features of mini- and maxi-computers in automation projects. By distributing the functions in a multi-computer system, the mini-computers can retain the responsiveness and reliability of simple configurations while the more extensive information handling is performed by the larger host computers. This approach overcomes most of the problems found with independent small control systems on one hand and over-extended, centralized computer systems on the other. This philosophy is illustrated with actual applications at Ford Motor Co.

The “real world” of highway truck operation sometimes differs from the technical world of simulation models, laboratory and proving ground tests and mathematical equations. At this time this is a matter of real concern. Federal standards now being proposed and effected appear to be based on the maximum performance-or greater-that can be built into a vehicle fresh off the production line. Generally speaking, when the truck or trailer comes off the production line it is, or should be, at the peak of its lifetime performance. Therefore, it is disturbing to see a trend, at state and federal levels, to impose new truck standards or standards even more severe on vehicles in actual operation, especially combinations of vehicles whose individual units, even though adequate when tested alone, cannot, when combined, attain such individual unit standards-that is, without exorbitant costs which will eliminate them entirely from the highways.

This paper gives a comprehensive analysis of tire-road traction, utilizing new experimental and analytical techniques. It introduces a concept of traction envelope for evaluation of the overall tire traction properties in all operating modes on a common basis. It establishes feasibility of laboratory techniques for tire wet traction measurements and shows good correlation between road and laboratory measurements and also between road measurements on different surfaces. Comparative evaluation between new and conventional techniques for measuring tire traction on the road in cornering with and without power application are given.

An analysis was made of vibration phenomena in the steering system of a vehicle, when the front wheels have some amount of unbalance. The program included vehicle running tests and bench tests to ascertain some of the factors influencing vibration behavior. A mathematical model of the vibration system was simulated on a digital computer in as much detail as possible. The resultant understanding of the dynamics of the system as a whole led to an extensive theoretical analysis of selected key parameters.