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The problem of the rotating cylindrical shell under the action of a stationary point load is treated in detail as a means of approximating the action of a tire while rolling. Comparison is made between calculated and measured load deflection curves, using a model very similar to the postulated cylindrical shell. There is reasonable correlation between such dynamic load deflection characteristics as predicted from the model and obtained experimentally, so that some support is lent to the eventual application of this model as an analog for real pneumatic tire studies.

Methods of manufacturing and characteristics of polished plate, float, sheet, clear, tinted, shaded, tempered, laminated, and special glasses are briefly described. Codes, laws, and specifications governing automotive glass use are reviewed. Present practices in automotive glass use are presented; future possibilities, compatible with apparent automotive trends, are discussed with particular attention to thin glass, electrically heated, and “roof” glasses.

An elastically supported cylindrical shell is used to represent the motion of a pneumatic tire in the plane of the wheel. This is an attempt to utilize shell motion as an analog to the plane motion of the pneumatic tire tread. The idea is suggested by the constructional features of a pneumatic tire, both from the point of view of mass distribution and the distribution of elastic stiffness. The equations of motion for such a model are derived by reference to conventional energy methods. In this derivation, the influence of internal pressure and elastic support of the shell is taken into account. The frequencies are determined as functions of the mode shape, and it is shown that nodes, as well as antinodes, rotate with an angular velocity somewhat less than the angular velocity of the rotating pneumatic tire, to an extent determined by the particular mode shape in question.

Methods are presented for calculating dynamic contact patch areas of an elastically supported cylindrical shell used to model the dynamic rolling of a loaded pneumatic tire. These areas are shown to be influenced considerably by rolling velocity, constructional parameters of the tire, and its loss characteristics. Dynamic pressure distributions within contact patch areas are obtained analytically, and the techniques involved are given. The shell is used as a basis for calculating load carrying and drag properties of a pneumatic tire so that various tire parameters may be approximated. The results given here are typical of information obtainable from such a model.

Corrosion of automobile bodies is caused by electrochemical action from a hostile environment. Prevention of corrosion is complicated by factors of environment, design, manufacturing, and inherent characteristics of materials. These factors are discussed in some detail, as are the problems generated by new materials such as galvanized steel and zinc rich primers. Various methods of imparting corrosion resistance are considered as well as those finally adopted. Electrocoating appears to approach the ideal protection.

Regulatory bodies, both Federal and State, are currently very active in proposing new brake regulations in the interest of safety. Some have already been enacted and many more are sure to come. They will contain many “firsts” in brake legislation, some of them good and some bad. It is certain that in many instances a reevaluation of existing brake systems will be necessary while in other cases development of new components will be required. The automotive industry should do all it can to promote legislation which is based on sound engineering principles.

Many new air brake component designs and brake system developments for commercial vehicles are a direct result of state and federal current and proposed legislation. Air brake systems are more complex where brake laws specify operating function of the equipment rather than vehicle brake performance. Steady improvement in brakes and brake systems will continue as we establish performance standards of brake control and braking effectiveness.

A group of industrial gas turbine fuel controls has recently been developed which shows considerable promise for use on industrial gas turbines. The basic design philosophy was to provide fuel controls consisting of fuel metering valves and standard industrial governors to meet the majority of individual customer requirements. These new metering valves schedule fuel flow as a function of compressor discharge pressure, and include flow schedule biases by inlet temperature and turbine temperature, and adjustments for fuel specific gravity and Btu content.

The high-speed performance of the conventional multi-cylinder coil ignition system is limited by the reduced contact dwell times with increasing speed, and by the mechanical limitations of cam operated contact breakers. The introduction of semiconductor devices, and their continued development, has enabled a racing eight-cylinder contactless ignition system to be produced, capable of providing ignition for engine speeds up to 15,000 rpm. This system is described, along with a transistor assisted contacts system and a contactless system for conventional vehicles.

Combustion tests utilizing liquid propane have successfully demonstrated that this fuel can be burned in a natural gas turbine combustion system, provided the liquid does not vaporize in the fuel nozzle. Procedures for nozzle design are given and modifications of the existing natural gas fuel system for dual-fuel application are discussed.

The severe temperatures encountered in aircraft at speeds above Mach 3 have created a need for highly efficient use of the fuel supply on board the aircraft as a heat sink for the cooling system. Since the fuel temperature limitations and heat rejection characteristics of the present fixed displacement fuel pumps represent inefficiencies in the system, the use of higher efficiency variable displacement piston type fuel pumps is analyzed. The design of such a pump is shown to be practical and within the present state of the art. It is shown that the effect of the change on the fuel control system is moderate and requires no new or untried techniques.

The problem of scaling down fuel control components for small (1000 hp or less) gas turbine engines and the tradeoff of cost versus performance is discussed. A comparison of design approaches versus requirements is presented to illustrate the type of compromises that must be considered. The effect of engine design requirements is presented in terms of control complexity and cost. Specific examples of design and the effect on cost of various requirements are discussed in detail. The examples of compromise versus cost are presented to illustrate “cost effectiveness” of performance requirements and a general method of how lower cost may be achieved.

The simple forced vortex pump design presented in this paper has demonstrated usefulness in satisfying the requirements of propulsion systems for aircraft and rocket motors. A simplified theory of design is expanded, and theoretical and actual performance curves along with sketches and photographs of this type of pump are presented. This pump, with its small size, light weight, high operating speed, and simplicity of design, establishes itself as a centrifugal type pump in a range of flows and pressures normally considered to be the domain of larger, heavier, more costly, and complex positive displacement pumps.

This paper describes a new electronic ignition system which provides trouble-free operation, while extending spark plug life to a warranted 50,000 miles or more. Design considerations are discussed that led to the development of a high-voltage capacitor discharge system whose performance justifies its premium cost. It describes how output voltage, available energy and output voltage rise time (the three major properties that determine overall ignition system performance) are used to establish the design features for new electronic ignition systems. Specific considerations are examined in detail, and appropriate mathematical computations are reviewed; for example, it is shown how energy storage and time constant relationships can be used to derive conditions for achieving ignition at higher engine speeds.

The American Motors disc brake is a development which represents a significant step forward in automotive brakes. This development was a joint program between American Motors and the Bendix Automotive Products Division, combining the engineering skills and experience of both corporations. This brake system, incorporating dual piston disc brakes on the front and non-servo drum brakes on the rear, was designed and developed against an advanced set of performance objectives. The new objectives recognize the increase in highway speeds on modern turnpikes calling for an increase in brake system high speed capabilities. The design of the American Motors disc brake involves operating pressures and temperatures requiring a lining of special characteristics. The development of a proper lining was a vital part of the overall engineering program. The use of Non-Servo drum brakes in the rear was the result of a complete review of the principles and objectives in front-to-rear brake balance.

This paper is a brief survey of the various methods in existence today for weighing heavy earthmoving construction equipment. Also considered are the problems, solutions of problems, and practices involved in the weighing of heavy construction equipment; and the progress made by LeTourneau-Westinghouse Co. in field weighing techniques.

The four-wheel brake system with separate parking brake was made available as standard equipment on the Chevrolet Corvette. This new system developed by Chevrolet and Delco Moraine meets specific sports car requirements such as increasing total braking effectiveness, giving more stopping power, and improving vehicle control through increased braking feel. The disc brake gives virtual fade free performance which is achieved through use of a ventilated disc which dissipates heat rapidly and keeps brake linings within their working temperature range. Intensive proving ground and road tests, as discussed in this paper, prove the overall performance of the disc brake system.

A brief review of the two classes of plastics, thermoplastic and thermo-setting resins, is presented. The physical and chemical properties of each class are described, and respective molding techniques detailed. Plastics in combination with metals are discussed, and production examples of this combination are described and illustrated.

The haulage cycle as a factor in successful operation of a mining property is described. At Kennecott a change over was made from rail to truck haulage as the best means for over burden removal. Factors determining efficient utilization of equipment in a haulage operation such as tonnage to be moved, grade and length of hauls, equipment capacity, maintenance, and weather conditions were evaluated. The method whereby computers were used to analyze these variables and to provide guide lines for optimum utilization of equipment is presented.