Search Results

Discussion of four factors pertinent to any overall ride evaluation. These factors are frame beaming, fifth wheel location, special body mountings, and variable loading conditions on tandem truck and tractor ride. The methodology for measuring the characteristics of these factors is reviewed and practical solutions for improved ride are given.

The presentation here of a computer program simulating an engine cycle emphasizes mechanical factors under the control of the engine designer rather than scientific aspects of combustion. Data secured by measuring valves, manifolds, and other parts on a flow bench are used to calculate instantaneous flow in and out of the cylinder for the firing engine. Heat transfer, finite time of combustion, and variable specific heat of the gas are also calculated. The program is particularly well adapted to indicating the direction and relative magnitude of the effect of changing one variable, such as valve size, at a time.

Empirical equations which describe, individually, the magnitude of the most important factors determining the cycle efficiency and motoring friction of an engine are derived from experimental data. These equations are organized into a computational procedure which recognizes the interdependence of these factors and provides a method for estimating the overall efficiency of any given engine. A mathematical experiment using this analytical method is described. The results of this experiment are presented to show the overall effect of these factors when varied individually or in combinations on a hypothetical engine.

Under a new program of quality control in the field of powder metallurgy automotive parts called quality assurance, the supplier is made a closer partner with the buyer to get a more dependable part that consistently meets all requirements and specifications. The quality assurance program consists of review of potential suppliers, contract negotiations, initial quality assurance surveys, and routine quality assurance surveys.

Investigations of the non-flame oxidation of exhaust gas hydrocarbons and carbon monoxide are reported. These investigations cover basic studies of the relationship of temperature, oxygen, and residence time to oxidation rates with external, supplementary, exhaust gas heating. Reaction (oxidation) is then shown to be possible without supplementary heat in the test installation of a homogeneous reactor on one cylinder of a V-8 engine on an engine dynamometer. Vehicle tests were then conducted to determine the operational characteristics and oxidation performances of a series of multi-cylinder reactors mounted on 292-cubic-inch-displacement engines. Unique methods of air introduction and heat conservation are described. These reactors were capable of effectively decreasing exhaust concentrations of hydrocarbon and carbon monoxide while the vehicles were driven over a traffic route. Tests of two reactors designed especially for fast warm-up are reported.

THE AUTOMOTIVE industry has not yet taken full advantage of all the superiorand peculiar properties of the new elastomers. To accomplish this, components must be designed around the material in contrast to the more normal procedure of fitting a material to an established design. Examples of progress are: colored rubbers that withstand weather indefinitely; elastomers that seal the most deteriorating hydraulic and lubricating fluids at temperatures in excess of those practical from the standpoint of the stability of the fluids themselves and the effects of heat upon metal components; the fact that the long-sought 100,000-mile tire is imminent. This paper discusses the properties and potentials of some of the new elastomers, with some possible applications.*

THE Free-Piston Engine Program described in this paper was concerned with determining thermodynamic relationships of small, high-speed engines. The purpose was to establish proper engine geometry and mechanical design which could then be applied to developing larger automotive engines. The author outlines the problems encountered during the Program's beginnings: starting system, powerplant assembly, cooling system, and lubrication. The results indicated that the free-piston engine would be particularly applicable to the farm tractor. The author thinks that such a powerplant may equal or better the diesel engine in economy.

INVOLUTE SPLINES enjoy three major advantages over their straight-sided counterparts: 1. New design concepts have given a more rational approach to clearances and errors. 2. Manufacturing is cheaper and more accurate. 3. Gaging is simpler. Thus, the involute spline standard of SAE and ASA continue to take precedence over the older straight-sided standards.

RUMBLE is a low-frequency noise heard in high compression engines and accompanied by high rates of pressure rise. Thus, rumble indicates a rapid combustion process. This paper describes a method of studying this problem: by detection of flame fronts by ionization gaps. Results of experiments show that rumble is caused by deposit ignition in the end-gas region. These multiple ignitions occur after the normal flame front has progressed partially across the chamber. The authors conclude that this type of deposit ignition is generally a self-sustaining process, lasting until the deposits are burned out at a particular engine performance level. When the level is increased, the process repeats itself.

AMONG the many outstanding advantages of the shell molding process of casting crankshafts, as described here, are the following: 1. Manner in which entire process responds to a high degree of automation. 2. Close tolerances that can be maintained from casting to casting. 3. Raw sand requirements are reduced from 125 lb (previous method) to 20 lb. 4. Results in 70% reduction in weight of chips produced. 5. Resulting crankshafts have highest wear resistance and exceptional endurance. 6. Gives additional design leeway: Allowing the most efficient distribution of weight. Contributing to engine compactness by varying the casting contour to prevent potential interferences.

IN 1957 Ford introduced in its passenger cars a new rear axle incorporating a straddle-mounted pinion. This paper describes the development and features of the 2¼-in. offset axle. The author thinks the most interesting feature of the development problem was the design of the hypoid gears. The 1957 gears were designed with the deepest possible teeth to give maximum fatigue strength. They maintained the conventional scheme of 50 deg on the pinion and about 15 deg on the gear.

THIS paper describes the development and utilization of a new Ford free-piston power-plant, the model 519. Mr. Noren traces the development of the engine from the initial idea to the point where commercial utilization could be considered. Mr. Erwin describes one commercial use: in the Typhoon tractor. The ratio of size and weight to horsepower is favorable for farm tractors, being smaller and lighter than equivalent diesel engines. The performance of the tractor has been satisfactory thus far, operating smoothly and being practically vibration-free, with little noise. The advantages of the free-piston gasifier, as reported by the authors, are: flexibility, fuel economy, no need for auxiliary starting engine, economical manufacture of a wide range of engine sizes, adaptability to a wide range of fuels, and good torque characteristics.

THIS paper discusses the free-piston engine which is being investigated by Ford. The analytic method for calculating free-piston-gasifier thermodynamic performance over the complete operating range is discussed for the given limitations and conditions. Using these analytical methods, an automotive-size free-piston and matched turbine was designed, built, and tested.

AMONG the difficulties usually associated with measurement of combustion-chamber volume by liquid methods are amount of time required, contamination of combustion-chamber deposits, and inaccuracies arising from entrapped air. Use of a gaseous fluid such as air as the measuring medium eliminates most of the objectionable features of volume measurement with liquids. Techniques utilizing air for volume measurement fall into two basic classifications: dynamic or sonic methods, and static or pneumatic systems. Cylinder leakage and acoustic damping by engine deposits affect the accuracy of volume measurements based on dynamic properties of combustion-chamber volume, hence small volumes occupied by combustion-chamber carbon deposits must be measured separately by static or pneumatic means.

IN THE first part of this paper dealing with the metallurgical aspects of the camshaft-tappet problems met with in the design of the new Ford overhead-valve V8 engines, Messrs. Laird and Stevens describe the events which led to the adoption of the as-cast alloy-iron camshaft, nitro-carburized martensitic tappet combination. The combination cited works well in the engines described, but it is not implied that it will perform satisfactorily elsewhere. In the second portion of the paper, Mr. Iles discusses the test schedule devised in connection with the development of the camshaft-tappet materials in the new engines. It is stated that important findings will occur when such tests involve a large number of parts, making possible the study of results on a frequency basis. Tests have shown that a predominantly martensitic tappet structure results in superior performance in combination with the as-cast alloy-iron camshaft used.

THIS paper reports on progress to date in the development of high-temperature alloys for automotive gas turbines. Strict limitations have been set on the alloying elements in order to keep costs down — the cost factor being the main reason for this alloy search. The materials discussed here, which meet the alloy limitations and the temperature and stress requirements, fall into three classes: 1. Iron-base chromium - manganese - nitrogen austenitic alloys. 2. Iron-aluminum ferritic alloys. 3. Cast ferritic alloys with up to 12% chromium and some titanium, vanadium, molybdenum, and tungsten.

ONE plastic model is worth 40 lb of blueprints and 40 hr of the explaining that goes along with the prints, according to engineers who have worked with the new plastic “toys” which can serve as perfectly scaled miniatures for virtually every phase of automobile design and manufacture. The extensive benefits occasioned by this revolution in methods may be summarized thus: 1. Shortens design development time by providing a third-dimension evolvement of structure and form. 2. Used in advance discussions for compromising engineering and manufacturing problems, showing construction so clearly that troublesome problems are foreseen; thus enabling clear-cut, reliable decisions with a minimized chance of encountering major revisions. 3. Show in one minute what could not be found on prints for hours, saving time over any other methods, while generating valuable counterproposals reducing costs, operations, man-hours, and so forth. 4.

PROPER protection of metal parts operating as bearing surfaces, or in contact under relatively heavy loads, during the break-in period often means the difference between successful operation and failure. Various surface coatings have been investigated to discover which ones will give this protection. The authors discuss here three types of surface treatment for cast-iron and steel that do give superior wear and scuff resistance.