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1922-01-01
Technical Paper
220012
S D HERON
The paper reviews some of the salient points arising in the design and development of the modern high-output air-cooled cylinder. It is based to a very large extent upon the work of Dr. A. H. Gibson at the Royal Aircraft Establishment, which in turn was principally a development of the pioneer efforts of Renault, supplemented by some post-war work of the author for British companies and tests made by the engineering division of the Air Service. While the paper may, therefore, lack somewhat in originality, many of the results presented, it is stated, have not been published previously. The problems of an aircraft cylinder of approximately 40 b.hp. are dealt with primarily, but some aspects of automobile-engine cylinder design are considered. The first point treated is the heat to be dissipated, this being followed by a consideration of how to secure an even temperature-distribution in the various parts of the cylinder.
1922-01-01
Technical Paper
220006
O C BERRY, C S KEGERREIS
Stating that present internal-combustion engine fuel is too low in volatility for economical use and that this is the cause of engine-maintenance troubles, the authors believe that, since it is not possible to obtain the more volatile grades in sufficient quantity, the only hope of remedying this condition is to learn how to use the heavy fuel, and that the most promising method of doing this lies in the effective use of heat. As the experimental data regarding the best temperature at which to maintain the metal in a hot-spot manifold and the range of temperatures available in the exhaust gases are meager, the authors experimented in the Purdue University laboratory to secure additional data. They present a summary of the results.
1922-01-01
Technical Paper
220003
THOMAS MIDGLEY, W K Gilkey
The paper is intended to familiarize automotive engineers with the general subject of spectroscopy, by pointing out the various methods that can be employed to determine the actual instantaneous pressures obtained in normal combustion, the temperature-time card of the internal-combustion engine and the progress of the chemical reactions involved in normal and abnormal combustion. The subject of spectroscopy is outlined and explained, illustrations are presented of different types of spectra, and spectroscopes and their principles are discussed. The remainder of the paper is devoted to an outline of what the spectroscope can reveal about the nature of combustion.
1922-01-01
Technical Paper
220029
E W TEMPLIN
Stating that the means and methods of transporting freight over the highways are governed by six factors, the author enumerates them as being the number of ton-miles of goods to be shipped, the shipping points and destinations, the kinds of highway available, the types of vehicle most suitable, the cost of operation per ton-mile and the rates that should be charged for the service. The purpose of the paper is not to answer these questions but to determine whether present practice is headed in the right direction. The conditions the highway must meet, in addition to the gross load of the vehicles, are the maximum tire load, the pressure per square inch exerted by the tire upon the pavement and the value of any impact blow upon the pavement. The impact blows of pneumatic tires are practically negligible, while solid tires build up the impact to many times the weight of the wheel load; this is proved by impact tests of tires which are described in some detail and illustrated.
1922-01-01
Technical Paper
220030
C Fayette Taylor
After indicating the line of development since November, 1918, toward making the internal-combustion engine better adapted to aircraft service, the successful application of the supercharger to improve engine performance at great altitude is described and the over-dimensioned and over-compressioned engine also is discussed as a means toward that end. The use of anti-knock compounds to permit the use of high compression-ratios at small altitudes without knocking is commented upon and engine size is considered for both airplane and dirigible service. Further review includes air-cooling experiments in reference to the air-cooled radial engine, refinement of aviation-engine details, and improvements in aircraft powerplant parts and fuel-supply systems. For commercial aviation, powerplant reliability and low cost are stated as essentials. Illustrations are presented of the supercharger and of the engines and sylphon fuel-pump mentioned.
1922-01-01
Technical Paper
220035
O C BERRY
Economy tests carried out in France indicate that it is possible to obtain a larger number of miles per gallon from cars made there than from cars made in this Country. The author states that it would be well to make a careful study of the factors influencing car economy and to assure that our future car models take full advantage of all possible means of increasing their economy. Figures are presented showing the extent to which economy can be increased by changing such factors as the carbureter adjustment, time of the spark, rear-axle ratio and speed of driving. A car that normally will go 21 miles per gal. under favorable test conditions at 20 m.p.h. was increased to 43 miles per gal. at 20 m.p.h. The study is not complete but has gone far enough to demonstrate its value. This progress report is presented to stimulate thought.
1922-01-01
Technical Paper
220040
P M HELDT
The gradual trend toward overhead valves in automobile engines, as indicated by an increase in their use on American cars from 6 per cent in 1914 to 31 per cent in 1922, has been accelerated, in the opinion of the author, by their successful application to aircraft engines and by the publicity given them by their almost universal adoption on racing machines. Tractor engines recently brought out show the advantage of this construction.
1922-01-01
Technical Paper
220043
JOHN MAGEE
The author believes the piston-ring problem to be an engineering one worthy of serious study and that it should be possible to standardize types and sizes in a way that will go far toward elminating present difficulties. It is stated that cast iron is the only satisfactory metal suitable for use in the internal-combustion engine and that the foundry offers the greatest opportunity for improvement, in the elimination of poor castings. The superiority of individually cast rings is averred and a formula for their composition is given. Leakage and oil-pumping are discussed, followed by comment upon the width and form most desirable for piston-rings; and some of the difficulties of their manufacture are enumerated, together with suggested improvements, inclusive of inspection and testing methods.
1922-01-01
Technical Paper
220042
FERDINAND JEHLE, FRANK JARDINE
The lightness and high thermal conductivity of aluminum pistons are conceded and the paper deals principally with their thermal properties, inclusive of the actual operating temperature of the pistons, the temperature distributions in the piston and the effects of the cooling-water temperature and the piston material on the piston temperature. The apparatus is illustrated and described, and charts are presented and commented upon in connection with a discussion of the results obtained. Theories affecting piston design are presented and discussed, reference being made to diagrams relating to design procedure: The work is supplementary to that done in 1921 by the authors, which they presented in a similar paper to which they refer.
1922-01-01
Technical Paper
220024
B M IKERT
After generalizing on the need for greater consideration in automobile design for service and maintenance requirements, the author discusses the accessibility of car parts at some length with the idea of pointing out difficulties encountered by service-station mechanics when parts are inaccessible, this having a bearing also on the length of time required for repair work and the consequent increased cost to the car owner. Specific instances are given and illustrated in which improvements in design could be made to obviate trouble. These are inclusive of cylinders, cylinder blocks, pistons, bolts, cap-screws, nuts, valves, dashboard instruments and general take-up adjustment. Special emphasis is placed upon certain inaccessible parts that necessitate excessive dismantling.
1922-01-01
Technical Paper
220063
GEORGE E A HALLETT
The general method of procedure taken by the Air Service before beginning the actual design and construction of the necessary types of aircraft engine is outlined and the four steps of the development subsequent to a very complete study of existing domestic and foreign engines are stated. After checking over the layouts, if all the details are agreed upon by both the designer and the Engineering Division, the contract is placed, usually for two experimental engines, and the construction work is begun. Acceptance tests are made to demonstrate that the engine is capable of running at normal speed and firing on all cylinders. These are followed by the standard performance test made on the dynamometer at McCook Field. The results of the latter test determine whether the engine can enter the 50-hr. endurance test. The engine is then torn-down and inspected for wear. Suggested modifications are embodied in reconstructed engines which eventually fulfill the requirements.
1922-01-01
Technical Paper
220045
H G FARWELL
The author describes the major features of brake and clutch practice that he observed in 1920 while traveling in England, Belgium, Italy and France, comparing them briefly with American practice of the same period. He analyzes the types of brake and clutch used on 165 cars exhibited at the London automobile show of that year, giving the percentage of the different types in evidence. Numerous illustrations that are described and commented upon in greater or less detail appear in the paper and in the discussion which followed it, these being inclusive of most of the best-known types of brake and clutch in use in the United States and in Europe.
1922-01-01
Technical Paper
220047
H M Crane
The author indicates what the history of spring-suspension has been but discusses only the conventional type of four-wheeled design in which the front wheels are used for steering and the rear wheels for driving and braking. The problem of front-axle spring-suspension is mentioned, but that of proper rear-axle spring-suspension, especially for passenger cars, is discussed in detail because it is a much more difficult one. The advantages of the Hotchkiss drive for shaft-driven cars and some of its distinct disadvantages are stated, shaft-driven, rear-axle mountings being commented upon in explaining the factors that influenced the design of the spring-suspension device developed by the author. The advantageous features of this device are enumerated, inclusive of the effects of tire reactions.
1922-01-01
Technical Paper
220059
P E HAGLUND, I B SCOFIELD
The authors state the principles governing intensive quantity-production and describe the sources and methods of handling the basic materials that compose the Ford engine-cylinder. The fundamental plan of the River Rouge plant is outlined, illustrations being used to supplement the text that explains the reasons governing the location of the various units of the plant. Details are given of the use made of conveyors with the idea of keeping everything moving. The relation of the blast furnace and coke ovens to the engine cylinder are commented upon, the powerhouse and foundry are described, and the production of the cylinder is set forth step by step.
1921-01-01
Technical Paper
210012
C F KETTERING
Two distinct problems are involved in fuel research work, multi-cylinder distribution and the chemical constitution of the fuel mixture after it enters an engine cylinder. In discussing elementary combustion, the author refers to the components of the energy of combustion as gravitational, kinetic and barometric, and elaborates his theme with the aid of diagrams and charts showing normal and abnormal combustion. After emphasizing the necessity of theorizing at some length, anti-knock substances are discussed, inclusive of substances apparently dissimilar that have the same chemical constituents. The ignition point and fuel utilization are treated, followed by comments upon fuel studies that have been made, with accompanying indicator-cards. The future objectives of fuel research are outlined as being along lines of physical and of thermo-chemistry, the simple laws of elementary physics, and cooperation with the producers and refiners of the fuel.
1921-01-01
Technical Paper
210029
L L SCOTT
The paper describes the steam-operated 2-ton truck developed by E. C. Newcomb and the author. It has a direct drive-shaft from the engine to a rear-axle worm, with a 5 to 1 gear-reduction at the axle, and is operated without any transmission or clutch. The engine has been simplified since the author's first report on it in 1919, the changes relating to valve-gear, crankshaft and cam design. After presenting illustrations and describing them, the author gives nine specific advantageous features in this steam powerplant and comments upon them, submitting charts of torque curves which are analyzed. The engine control, fuel, oil and water consumption are next described and discussed and the results of acceleration tests are then shown in tabular form, with comments thereon.
1921-01-01
Technical Paper
210028
N J OCKSREIDER
In this day of transportation engineering, the requirements of each customer must be diagnosed accurately and the economic waste due to wrong selling eliminated. Stating that 32 classes of trades, divided into 350 sub-classes, use motor trucks, the author expresses the view that, in applying the science of selling by analysis, it is necessary to know the cost of shipping every pound of goods, deducing in turn the correct size of truck for a given kind of work. Referring to the fact that a truck cannot be designed to stand up under all conditions and that selling a truck which is unsuitable for a particular task means a dissatisfied customer, the author gives the opinion that a truck of mediocre merit will in many cases perform more satisfactorily than the best truck built operating under improper conditions.
1921-01-01
Technical Paper
210007
KINGSTON FORBES
The field of body engineering is broader than it is ordinarily considered to be; the author's intention is to bring to the attention of the automotive industry the breadth and scope of body engineering and outline the way this side of the industry can be considered and developed. After describing the body engineer's position, the author then discusses at some length the conflict between art and economy in this connection. He classifies a body-engineering department under the six main divisions of body construction, open and closed; sheet metal, body metal, fenders, hood, radiators and the like; trimming; top building; general hardware; painting and enameling, and comments upon each. Following this he elaborates the reasons for need of attention to details in body designing and mentions the opportunity there is at present for bringing the materials used in body construction to definite standards.
1921-01-01
Technical Paper
210038
BENJAMIN F BAILEY
The author uses some analogies of mechanical things to illustrate the underlying facts that must be considered in connection with electrical ingition, the first being that of an automobile starting under the influence of a constant force, which is analogous mechanically to the old touch-spark ignition circuit in that the velocity of the automobile corresponds with the velocity or speed at which the electricity is moving through the circuit. In similar manner the analogy is extended to include car acceleration and its acquirement of a certain store of energy as an illustration of electrical-energy storage as the current through an induction-coil is increased; and further analogies are made, numerous diagrams being presented. Battery and magneto-ignition similarities are treated in a similar way, short and long sparks are discussed pro and con and spark lag is considered in general terms.
1921-01-01
Technical Paper
210039
LOUIS CHEVROLET, C W VAN RANST
In addition to using a smaller quantity of fuel per horsepower-hour, the small high-speed internal-combustion engine has other important features of advantage which are stated. The authors outline specifications intended to secure these advantages. The high-speed racing engine designed by the authors, which won the 500-mile race on the Indianapolis Speedway in 1920, is illustrated and described in detail, its distinctive features being commented upon. The automobile should be built to a higher standard for the use of the high-speed engine. The builder should work to a greater degree of precision and, as the working parts of the engine are all light and stressed fairly highly, this necessitates the use of properly heat-treated high-grade materials. Few small cars of this type seem to give satisfaction. The authors look for further developments to counteract this in the near future.
1921-01-01
Technical Paper
210034
G C DAVISON
It is stated that, in the commercial motor boat field, the boat owner must choose between the various types of internal-combustion engine, broadly speaking there being three forms of such engines available today in small and moderate sizes; (a) the gas engine, (b) the surface-ignition or hot-bulb engine and (c) the Diesel engine. Charts are presented which show certain approximate costs of operation of the three types for various sizes of engine. Fuel and lubricant economy are discussed in connection with the question of the choice between a Diesel and a hot-bulb engine and, in regard to mechanical operation, it is stated that there is little choice between any of the three types under discussion, since all are reliable. For sizes of 100 b. hp. and less, some form of hot-bulb or surface-ignition engine has the field to itself, but for sizes above 100 hp. the Diesel engine shows its superiority.
1921-01-01
Technical Paper
210035
HOLBROOK C GIBSON
The author describes the type, size and general characteristics of the engines with which the German submarines were equipped at the time of the surrender, after having personally inspected 183 of them at that time, and then presents the general details of construction of these engines, inclusive of comments thereon. The maneuvering gear for such engines receives lengthy consideration and the reliability of engines of this type is commented upon in some detail, the author having confirmed his opinion that the German submarine engine is extremely reliable. One of the controlling factors in the design is that the Germans had investigated steel casting to the point where the successful production of steel castings was an ordinary process, and the author believes this to have been largely responsible for the success of the German submarine engine.
1921-01-01
Technical Paper
210049
FRED C ZIESENHEIM
The paper is divided into three parts; the fuel problem, the selection of the most economical internal-combustion engine for adaptation to automotive purposes and the details of the development work undertaken. After stating the fuel problem, inclusive of production, volatility and price charts, the methods of increasing the engine-fuel supply, the characteristics of present engine fuels and general considerations regarding the selection and adaptation of the most economical engine are discussed. Classifying internal-combustion engines as being of low, medium or high compression, the essential factors, advantages and disadvantages of each class are commented upon in detail. High-compression engines are classified, as to their method of injecting the fuel into the combustion-chamber, into the three general classes of air, gas-pressure and mechanical injection.
1921-01-01
Technical Paper
210052
HERBERT CHASE
The objects of this paper are to (a) set down in convenient form for reference purposes particulars concerning American and British practice in clutch design, (b) compare the advantages and disadvantages of various types of clutch and (c) give some notes on the theory of design without attempting comprehensive treatment of the numerous factors involved. The descriptive portion deals almost entirely with clutches used on passenger cars and trucks, but some of the clutches described are applicable to other automotive uses. The notes on the theory of design apply in general to all automotive clutches. The clutches considered are divided into the four general classes of cone, single-plate, multiple-disc and shoe-or-band types, these being discussed at length and illustrated with drawings. After a consideration of the details of their design and a brief presentation of the subject of clutch brakes, the notes on the theory of clutch design are presented.
1921-01-01
Technical Paper
210050
H H Platt
The purpose of piston rings in an internal-combustion engine is to reduce to a minimum the leakage of gas from and the seepage of oil into the combustion-chamber. Asserting that the widely held idea that the leakage of gas past the piston can be eliminated by the use of good piston-rings is incorrect, the author states three possible paths for such gas-leakage and, after commenting upon them, discusses diagonal and lap joints and the subject of leakage with special reference to them. After considering the design of rings for gas-tightness, the author shows a fortunate mathematical relationship, in connection with the application of uniform radial pressures, regarding the bending-moment stresses. Oil leakage is treated in a similar manner and the conclusion is reached that the properties of the material used are of extreme importance.
1921-01-01
Technical Paper
210047
F C MOCK
The author selects and sets forth some of the main laws and basic considerations influencing carbureter action. A brief defense of the carbureter as a means of supplying fuel to an engine is made, as compared with the fuel-injection method, and conditions in the cylinder, the manifold and the carbureter during normal operation are stated. The relations of throttle positions, manifold vacuum and engine torque are discussed, followed by an exposition of the effect of manifold vacuum upon vaporization. The subject of air-flow in carbureters is treated at some length and the venturi-tube form of air-passage is commented upon in considerable detail. The flow of air through air-valves, fuel-flow and mixture-proportion requirements are given detailed consideration, the last being inclusive of passenger-car, motor-truck, tractor, motorboat and airplane needs. The essentials for obtaining accurate information with regard to carbureter and engine tests are outlined.
1921-01-01
Technical Paper
210045
C A FRENCH
Stating that the knowledge now available does not permit an exact scientific definition of flame and giving the reasons, in this paper the author regards flames as gases rendered temporarily visible by reason of chemical action, discusses their physical rather than their chemical aspects and, unless otherwise indicated, refers to the flames of common gasoline and kerosene only. To gain a reasonably clear understanding of the requirements and characteristics of the different kinds of flame, it is necessary to begin with a study of atoms and molecules. The author therefore discusses the present atomic theory, the shape of the atom and molecular structure, and follows this with a lengthy detailed description of the beginning of combustion. The requirements and characteristics of the inoffensive variety of combustion are considered next and nine specific remedies are given for use in accomplishing the burning of heavy fuels with a blue flame in present engines.
1921-01-01
Technical Paper
210048
W S JAMES
The paper analyzes and states the factors affecting the power requirements of cars as rubber-tired vehicles of transportation over roads and the factors affecting the amount of power supplied the car as fuel to produce at the road the power required for transportation. Quantitative values are given wherever possible to indicate the present knowledge of the relation between the factors involved, and the text is interspersed with numerous references, tables, charts and diagrams. Among other important factors specifically discussed are mixing and vaporization, charge quantity control, the heat of combustion, gas-pressure, transformation loss and power transmission efficiency. Six appendices contributed by other associates of the Bureau of Standards are included.
1921-01-01
Technical Paper
210046
G P DORRIS
About 1917 the heavy ends of the fuel sold as gasoline required such an amount of heat to vaporize them that the expression “crankcase dilution” appeared; now they have increased to a maximum boiling-point of 446 deg. fahr., which has made it necessary to go still farther in the direction of heat application. After a brief consideration of the relative heat-absorption of air and fuel and the time factor in its relation to vaporizing, the author describes experiments with a specially designed manifold for increased vaporization efficiency and presents photographs of the device. With this type of manifold it has been possible to eliminate crankcase oil dilution completely and effect a reduction in carbonization. The lubrication efficiency has been improved, as well as other features that are enumerated.
1921-01-01
Technical Paper
210043
DUGALD CLERK
The distinguished author begins with a short account of the principal actions common to all internal-combustion engines and then proceeds to a more detailed account of the experiments that have been made to develop the theory and establish the properties of the flame working fluid of those engines. The divisions of the paper are headed (a) short statement of cylinder actions, (b) the air standard, (c) flame, the actual working fluid, (d) knocking, pinking and detonating, (e) air and exhaust supercompression, (f) residual turbulence, (g) gaseous explosions, (h) flame propagation and recompression, (i) the specific heat of flame, and (j) conclusions. After treating (a) in considerable detail, the author discusses present efficiencies and knowledge in regard to the limits of the thermal efficiency possible in internal-combustion engines under (b), (c), (d) and (e), going into considerable detail and presenting and analyzing numerous diagrams and charts.