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The permanent magnet alternator as applied to automotive battery charging and portable engine service is discussed. Manufacturing procedure, magnetic material selections, and regulation means are described. Out put characteristics of several alternators are presented. Ignition on portable engines using the alternator is described.

The roller one-way clutch has achieved wide acceptance in today's passenger car automatic transmission and has proved itself able to operate satisfactorily under the high demands of this application. Careful attention to the various design parameters for the clutch and its races, and to development through test has resulted in excellent performance. The roller clutches being used in present transmissions are of the loose spring and roller type or the caged spring and roller type, both with individually spring energized rollers.

The benefits provided by phosphate coatings in reducing wear are ascribed to the controlled etching of the surface subjected to wear. Through tests it appears that the manganese phosphate coating is the most effective application, the reason being the number of larger pits formed by manganese phosphate and the greater amount of phosphate retained in these pits. Chemical reactions involved in the production of these coatings are reviewed together with a comparison of the reactions involved in some of the common phosphate coating baths. The effect of treatment of metal surface prior to coating and the type of coating bath used are compared by examining the coatings as produced and after burnishing. These coatings have been reported to provide wear resistance by removing surface irregularities after machining and lapping, increasing lubricating efficiency, and preventing welding under loads.

The characteristic wear of electroplated chromium on piston rings has changed over the past 15 years. The reasons for the change are discussed and a theory proposed for the wear mechanism. The theory is supported by engine test results, radioactive ring and cylinder studies, and metallographic exhibits.

Packaging Plastisols are liquid polyvinyl chloride dispersions which can be applied by conventional means such as spraying, dipping, and flow coating. They can be applied in film thickness of 2–300 mils and can be made to foam to give strippable coatings ranging from a soft resilent type to a hard tough type. However, they must be fused at 300–350 F. Plastisols have advantages of saving much space and labor. Also, they are fire retardant and resistant to exterior and chemical atmospheres. Parts can be coated, fused, and stacked in times ranging 3–10 minutes.

A design technique for applying pressure-lubricated plain journal bearings to small gas turbine engines is described in this paper. Design charts, failure criteria, and the concept of a load-speed diagram are presented for both film and boundary lubrication conditions, along with data on the successful application of journal bearings in the Ford Model 705 gas turbine engine.

Application of circumferential seals has shown this type of bore contact seal to have practically unlimited axial travel, to be an essentially fail-safe device, and to require minimal space requirements. Problems involving residual unbalance and sensitivity to pressure direction and fluid environment are examined, and steps that may alleviate such difficulties associated with circumferential seals are described.

This paper discusses the influence of rolling element and fluid film bearings on rotor dynamics of “high-speed” turbo-machinery. System critical speeds, rotor response to unbalance, instability, and turbulence are discussed. The types of fluid film bearings best suited for high-speed operation are identified. Examples of high-speed turbomachinery using rolling element, liquid film and gas bearings are presented.

An attempt is made to show some of the key mechanical difficulties inherent in designing shaft, bearing, and seal systems for three desirable types of small gas turbine engines. This is accomplished by showing the bearing, shaft, and seal system of a family of large turbine engines which has demonstrated its high reliability, high efficiency, and low cost per unit of power as the thermodynamic, material and structural component technology improves and as the design power requirement is reduced. Three different solutions to the problems posed above (for radically different applications) are offered. The first and second solutions are for sophisticated, efficient engines for weapon systems consideration (Types I & II). Solution three describes a potential industrial, low cost, high efficiency, moderately heavy engine. (Type III.) A summary is made of the key shaft, bearing, or seal problems which must be overcome for each of the three types of engines described.

Many propane conversions result in less than optimum performance because of a lack of information concerning variables and their resultant effect on engine performance, economy, and durability. Factors such as carburetor size, air-fuel ratio, spark advance, air cleaner restriction, exhaust back pressure, intake manifold heat, voltage requirements, spark plug selection and gap, riser height and design, and carburetor orientation are examined to increase the basic understanding of this fuel.

Curve-fitting functions are combined with transfer functions and special parameter groupings to demonstrate that amplitude-limiting effects of hydrodynamic bearings on vibrations associated with critical speeds of flexible rotors are due to nonlinear characteristics. It is shown that stable and/or critically-damped operation can be achieved by designing bearings within proper ranges of a “dynamic load number” and controlling unbalance expressed as principal axis deviation related to clearance. The form of the attitude angle function is shown to be particularly significant with respect to unbalance tolerance. Practical application techniques are illustrated.

Conventional calculations for rolling bearing application are not sufficiently accurate to satisfy the conditions of the speed and temperature environment of turbine engines. Abetted by high speed computers, modern rolling bearing analysis permits the more sophisticated optimization of rolling bearing selection, mounting and lubrication. A logical analysis and practical approach to bearing selection is presented using a typical turbine-driven power shaft as a model.

The complexity of developing automotive design to meet the competitive market demands has necessitated closely coordinated teamwork to solve the various engineering problems. This paper describes the development of the power unit and front axle of the Renault 16, from the initial specifications and engineering decisions through the manufacturing details and performance ratings of the final model.

A unique system has been devised to measure and telemeter critical temperatures of reciprocating engine components. A prototype has been used to measure the piston pin bearing temperature in a full-scale EMD 2-567D diesel engine.

This paper describes an automatic control safety monitoring and data logging system which uses a frequency modulation signal format. The theoretical aspects of FM signals are outlined and experimental data reported showing signal to noise ratios for vehicle recorded data. A new type of specialized digital computer and data logger is described and examples given of engine parameter computations.

Two experimental methods for determining scavenging efficiency of an operating two-stroke cycle spark ignition engine are discussed and compared. They are the gas sampling technique and the spark interruption technique. Necessary apparatus and instrumentation are described, as well as the method of operation.

This paper describes techniques that predict and analyze dynamic response of vehicles traversing random rough surfaces. Road irregularities are statistically classified by frequency and amplitude distribution. This classification determines the nature of random inputs to mathematical vehicle models and allows computer prediction of dynamic response of a simulated vehicle. Once inputs and models are defined, parametric analysis with output criteria specified statistically can be performed. This allows prediction of vehicle riding quality and evaluation of design concepts. Statistical analysis of accelerometer measurements on actual vehicles permits verification of the design process and meaningful comparison between vehicles.

A small-scale oxidation test for automatic transmission fluids has been developed. In the test air flow rates, temperature and catalytic activity can be closely controlled at desired levels. A test procedure for screening automatic transmission fluids is described. Data are presented illustrating the ability of the test to distinguish between different levels of oxidation resistance, the repeatability of the test, and the correlation achieved thus far with a presently used full-scale transmission oxidation test.

A comprehensive test program has been carried out to study the indicated effectiveness of personnel restraining devices in reducing injuries and fatalities in post office vehicle accidents. The program consisted of a series of simulated vehicle crashes utilizing a dynamic impact sled and three actual crash tests of postal vehicles. The seating configurations and restraint systems of the three basic types of postal vehicles were tested on the impact sled with an anthropomorphic dummy simulating the vehicle driver. Crash tests were simulated at various speeds, g levels, and angles of impact, with accelerometers and high-speed motion picture cameras used to monitor the significant variables observed during each impact test. At the conclusion of the simulated testing, a full-scale barrier impact test was conducted on each of the three types of vehicles under study.

While the collision of cars is not an exact science, the 1967 General Motors energy absorbing steering column shows what can be done in one area to improve the finished product through the achievement of a sequence of design goals. It is felt that, based on tests of a great number of vehicles, the energy absorbing column will definitely improve the driver’s chances of survival in a significant range of head-on collision conditions.