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1926-01-01
Technical Paper
260060
E. E. WILSON
The purpose of the paper is to point out the basic policies which have resulted in the fostering of air-cooled-engine development by the Navy, and to indicate where the development has led. Two roles played by naval aviation are designated “air service” and “air force.” The former term refers to the functions of naval aircraft which are contributory to the ships of the fleets, such as scouting and the control of gun-fire. The latter term refers to the functions which involve the use of aircraft as an integral and component part of the Navy's striking force, such as combat, bombing and torpedo launching. Seven different types of aircraft are required by the Navy for its different purposes, these being airplanes for training, fighting, observation, scouting, torpedoing, bombing, and patrol use.
1925-01-01
Technical Paper
250018
J W White
Inasmuch as the use of low-pressure tires has become established, the conditions of car design affected by them are reviewed, particular reference being had to the members of the chassis included under the term unsprung weight, namely, the axles, the wheels and the tires. Referring to the principles that underlie basic design, the author first investigates the effect on the steering of such changes and compromises from the perfect structure as failure of the king-pin to coincide with the vertical load-plane, the inclination of the king-pin toward the wheel, or the wheel toward the king-pin, or both, and the giving of a toe-in to the front wheels. Further modifications have served to reduce the car shock, to add to the strength of all the parts by increasing the dimensions, to improve the spring-suspension, and to reduce the car weight per passenger.
1924-01-01
Technical Paper
240045
HUGH G BERSIE
Classes of service already provided by the street-car and the passenger automobile influence the expectations of the motorbus passenger regarding the quality of transportation service afforded by the motorbus. If an operator persuades people to ride in his motorbuses, it will be because they offer safety, economy, convenience and comfort to a greater degree than that offered by competitive transportation media. Since the public has demonstrated that, under favorable conditions, it will patronize the motorbus to an extent that yields a profit to the operators, the future success of this means of transportation lies wholly within the control of the motorbus builders and those who operate it. Of the factors that determine the degree of success attained, motorbus-body design bulks very large. Discussion of the subject is presented from the viewpoint of the passenger, as the motorbus approaches him, as he enters it and as he judges the quality of transportation it affords.
1924-01-01
Technical Paper
240048
JAMES W CAIN
Referring to the McKeen gasoline-driven car and one of the gasoline-electric type that were introduced in the early part of the present century and were the pioneers among self-propelled cars for railroad use, the author ascribes their limited success to their excessive weight and to engine and transmission troubles. Both these types, he thinks, might have been developed successfully had the gasoline engine been in its present state of efficiency and reliability. The early attempts having been more or less unsuccessful, the construction of all types was discontinued during the war. More recently the progress in the design and construction of highway motor-trucks has caused them to be adapted to railroad service by applying flanged tires to the rear wheels, pivotal pony-trucks forward and a motorbus body for the carrying of passengers and a limited amount of baggage.
1924-01-01
Technical Paper
240036
JOHN A C WARNER
The ascertaining of the factors that determine the riding-qualities of automobiles and the methods employed in studying these factors and the lines along which research should be directed in an effort to improve riding conditions are proposed in this paper with a view to encouraging further helpful discussion of the riding-qualities problem. Relative to the first of these questions, the factors treated in this paper comprise (a) road characteristics with respect to the vehicle; (b) the vertical, the longitudinal and the transverse motions of an automobile, as well as small vibrations or oscillations of high frequency; (c) vehicle characteristics, such as springing, accessory control, tires, wheels, chassis frame, seating, body, engine and transmission, steering-gear, brakes, heating, ventilating and lighting.
1924-01-01
Technical Paper
240039
JOHN J MCELROY
An air-spring and a steel-spring combination has a characteristic load-curve that allows maximum flexibility in the general working-range of the axle yet has an increasing resistance to dissipate large shock-loads. By varying the compression volume in the air-spring, the load curve of the combination can be made more flexible or stiffer as occasion demands. Tests show that the steel-spring vibration alone had a duration of 5½ sec. with a period of 87.2 vibrations per min.; the combination, a 3-sec. duration with 60.0 vibrations per min. Field tests of front-axle movement were made, the test apparatus for these and other tests being illustrated and explained. The maximum axle-movement either above or below the normal line is increased when using air-springs, and the subsequent rebound shows more action on the underside of the normal line, the general tendency of the air-springs being to float the chassis on a slightly higher plane at the time of rebound.
1924-01-01
Technical Paper
240038
S P HESS
Riding-comfort is defined as the transportation of an automobile passenger in so easy a manner that the trip will be a pleasure and not a hardship. Since spring-suspension constitutes the basis of riding comfort in passenger-cars, the paper deals with some of the important factors that determine correct chassis spring-suspension. An analysis made by the National Automobile Chamber of Commerce of replies received to a questionnaire it circulated among 20,000 car-owners is presented in proof of the genuine interest the motoring public has in the riding-quality of a car and the variable factors that have an influence on spring-suspension are stated to be the type of spring used, its physical dimensions, the amounts of sprung and unsprung weight, frame construction, wheelbase dimension and the kind of material used. Horizontal, vertical and sidewise motions of a car are analyzed, and a periodicity chart is shown for passenger cars of from 112 to 116-in. wheelbase.
1924-01-01
Technical Paper
240026
J F WINCHESTER
Solicitation of sales and the delivery of the product to the customer constitute the most important operative features of the motor-truck fleet supervised by the author. Endeavor is made to install the vehicles in the various fields along standardized lines. The volume and the extent of the business and the topographical conditions of each locality determine the size and the mechanical equipment of the vehicle that is employed, and it is installed only after a study of all the conditions pertaining to its operation. Adequate training of vehicle operators, not only along mechanical lines but also as direct sales representatives of the company, is made a feature; and so is accident prevention. These interests are promoted in various standard ways and are furthered by the publication of “house organs.” After a vehicle is installed the slogan adopted is: Keep It Moving With a Pay Load.
1924-01-01
Technical Paper
240027
R E PLIMPTON
Operating costs and their relation to the age of the vehicle have been a subject of controversy for some time. One faction maintains that after a certain indefinite period it is economy to salvage or junk the equipment and replace the vehicles with later uptodate designs. The opposing faction believes that the costs depending on maintenance and operating efficiency can be kept fairly constant. Comparing a motor truck with a locomotive they cite the opinion of railroad officials that when proper running repairs are made locomotives can be maintained continuously in the same service and retain their original earning capacity for many years. When new locomotives are built it is usually for the purpose of replacing types that have become obsolete and the old ones are then relegated to some other branch of the service.
1924-01-01
Technical Paper
240023
RICHARD W MEADE
Double-deck horse-drawn buses did not meet with much favor in the United States, but from the earliest days have been popular with persons of all classes in England, probably due in part to the British nation's love of outdoors and in part to the governmental policy of prohibiting the carrying of passengers in excess of the seating-capacity. Packed vehicles continued to be characteristic of transportation in this Country until public service regulation in the early days of the present century required that a reasonable number of seats should be provided. When the number of passengers was limited to the number of seats, at the time of the introduction of motorbuses on Fifth Avenue in New York City, the failure of the experiment was predicted, whereas subsequent service has proved it to be the cornerstone of success. London double-deck tramcars with 78 seats require about 3 sq. ft. of street space per passenger, while the latest type with 50 seats require about 4 sq. ft.
1923-01-01
Technical Paper
230027
F C HORNER
The author discusses the factors that must be considered in solving the transportation problems and then describes the operation of the English-railway cartage-system in some detail under the two main divisions of delivery and collection. An important feature of the system is that of the control afforded by locating a controller, or dispatcher, in a central office and holding him responsible for the movements of the carmen, or drivers. The details of this control are explained. The field for the motor truck in railway-terminal service is outlined and a presentation is made of the merits and demerits of unit containers, together with an illustrated description of the English “fiats,” or demountable bodies. Other subjects treated include cartage costs, tonnage hauled, unified control of cartage and expressions of opinion quoted from numerous English trade organizations.
1923-01-01
Technical Paper
230030
Georg H. Madelung
ABSTRACT
1923-01-01
Technical Paper
230039
J G VINCENT, W R GRISWOLD
Stating the fundamental characteristics of the modern motor-car under the headings of performance, safety, economy, comfort and taste, the authors define these terms and discuss each basic group. The specifications of the car in which the single-eight engine is installed are given, and the reasons governing the decision to use an eight-cylinder-in-line engine are enumerated. Following a somewhat lengthy discussion of the components of engine performance, the design of the engine is given detailed consideration under its divisions of crankshaft design and the methods employed, gas distribution, the operation of the fuelizer, cylinders, valve gear and the arrangement of the accessories. Transmission design and the wearing quality of gears receive similar treatment.
1923-01-01
Technical Paper
230038
R ABELL
Specification is made of 13 essential factors that the author believes are necessary for attaining better engine performance; he then describes how improved results have been obtained by the use of a single-valve mechanism on an engine having an unusually high compression-ratio and using ordinary gasoline as fuel. The latest type of engine built with the single-valve mechanism is illustrated, and detailed descriptions of its development, design and operation are given, together with comments upon its factors of advantage and data obtained from tests. In designing this single-valve mechanism, the primary object was to solve the problem of positively closing poppet-valves without using springs and thus to produce a type of engine that would operate efficiently at greater speeds than are possible with spring-closed valves. Another object was to reduce the temperature of the exhaust-valve.
1923-01-01
Technical Paper
230025
BRAINERD TAYLOR
The paper is a presentation of a practical solution for the coordination of military and commercial transport with rail and water transport. The necessity for combining and coordinating transportation facilities with the idea of organizing a homogeneous transportation network of waterways, railways and highways, proved to be the essence of success in military operations during the World War. The utter inadequacy of pre-war and war-time transport facilities, when organized in the separate fields of railroad, maritime shipping and port operations, and the decentralized elements of highway transport, caused the United States Army to make a comprehensive study and plan of the world's war-time transportation with particular attention to the organization of motor transport as the necessary factor in coordinating all transportation facilities. The salient features and general principles of this study and the resultant plan are stated.
1923-01-01
Technical Paper
230023
C M EASON
The author (Chicago Tractor Meeting paper) divides the history of the application of mechanical power to farm work into three periods, reviews each one and comments upon the various phases of progressive development that influence the type of tractor most desirable for satisfying present needs. The requirements of farm work are outlined, and the different types of tractor built and being constructed to meet these demands are reviewed, discussion of large versus small tractors, type of drive, power needed, control, methods of operation and the factors constituting general-purpose service being included. So far as adopting the tractor for farm usage is concerned, the author believes that the present limitation of such utilization lies with the tractor industry and with tractor engineers, rather than with the farmer.
1923-01-01
Technical Paper
230056
E E LA SCHUM
The magnitude of the business of the American Railway Express Co. requires that careful consideration be given to the details necessary for economical operation. The equipment comprises 12,755 vehicles, of which approximately one-third are motor-driven and have a carrying capacity of more than one-half the total. On July 1, 1918, when all the express companies were merged into one organization, it was found that the motor-vehicle equipment included 59 different makes and 131 different models. Among the 377 trucks built by one company were 21 different models. Diversity of equipment, of course, complicates the maintenance problem and adds to the cost. Additional expense is incurred frequently by purchasing and experimenting with parts offered by makers of accessories such as carbureters, spark-plugs, wheels and the like. Careful inspection, adequate lubrication and the adoption of “stitch-in-time” methods will save needless expense.
1923-01-01
Technical Paper
230057
J LYMAN LARSON
A tract comprising several acres of “tamarack” swamp, drained with tile the previous fall and cleared of stumpage the following spring, was utilized to obtain accurate information regarding the tractor and the plowing equipment required for the heavy operations of first breaking of the peat soil, which was from 5 to 7 ft. deep. The paper describes the equipment used, gives details of the procedure and presents the data that were obtained. Three different types of tractor and two types of plow, the latter having either a marsh or a breaker bottom and equipped both with and without a furrow pusher were used. Specifications of the tractors and the plows are given and commented upon, graphs and tabulations of the results being presented also. Power requirements on timbered peat and on grass marsh are compared and the efficiency of the plowing equipment is discussed.
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
220018
G DOUGLAS JONES
Stating that the trend of tractor development must be toward the small tractor that is capable of handling all of the power work on a farm, the author quotes farm and crop-acreage statistics and outlines diversified farming requirements, inclusive of row-crop cultivation. Tractor requirements are stated to be for a sturdy compact design to meet the demands of the diversified farm, which include plowing, seeding, cultivating, hauling and belt-power usage, and these requirements are commented upon in general terms. Consideration is given to farm implements in connection with tractor operation, and the placing of cultivating implements ahead of the tractor is advocated.
1922-01-01
Technical Paper
220017
O B ZIMMERMAN, T G SEWALL
The authors enumerate some of the questions that are involved and, after outlining a previous paper on the subject of plows, analyze these questions in part by the aid of diagrams and applied mathematics. Comparative draft data are presented in tabular form and commented upon, as well as comparative hitch-length data. Tractor reactions are explained and discussed in some detail in a similar manner, special attention being given to the reactions on a slope and up-hill. The reactions on cross-furrow slopes are considered, comparisons being made between two tractors that were reported upon in the University of Nebraska tests. The factors involving tractor stability and resistance against overturn are analyzed. The authors state that the analysis presents a definite method of attack for the more correct solution of the proper hitching-point, as well as being a study relating to lug design.
1922-01-01
Technical Paper
220050
R E PLIMPTON
The author enumerates the distinctive features of buses designed for city, for inter-city and for country service and comments upon them, presenting illustrations of these types of bus. Steam and electric motive power are discussed and the chassis components for bus service are considered in some detail. The general types of bus body are treated, together with the influences of climatic conditions and local preferences. Comfort and convenience factors are discussed at some length and the problems of heating, lighting and ventilation are given constructive attention. Fare-collection devices and methods are commented upon, and the State and local legal regulations are referred to in connection with their effect upon bus operation. Illustrations are included and a table showing condensed specifications for city buses is presented.
1922-01-01
Technical Paper
220049
G A Green
In the paper an attempt is made to answer the broader phases of the questions: What constitutes a bus? and In what respects does a bus differ from other classes of automotive equipment? by establishing the principles on which the design and operation of motorbuses should be based. The treatment of the subject is in the main impersonal, although specific references to the practice of the Fifth Avenue Coach Co. and illustrations of its equipment are made to emphasize the points brought out. The questions of the unwisdom of overloading, rates of fare and the service requirements are discussed briefly as a preface to the paper proper. The factors controlling bus design are stated to be (a) safety, (b) comfort and convenience of the public and (c) minimum operating cost. The various subdivisions of each are commented on in some detail, and numerous illustrations and tabular data supplement the text.
1921-01-01
Technical Paper
210033
OSCAR W. SJOGREN
Before taking up the results of the tests, the author states briefly the provisions of the Nebraska tractor law, the kind of tests conducted and the equipment used. Applications covering 103 different tractors were received during the season; of the 68 that appeared for test, 39 went through without making any changes and 29 made changes. The results of the tests are described and illustrated by charts. The fuel consumption was studied from the three different angles of volumetric displacement, engine speed and the diameter of the cylinders, the tractors being classified accordingly and the results presented in charts which are analyzed. The weaknesses of the tractor as shown by the tests are commented upon at some length with a view to improvement of the product.
1921-01-01
Technical Paper
210030
N J SMITH
The object of this paper is to point out some of the difficulties of motor-truck maintenance and to suggest lines of improvement. The buyer and user of a motor truck sometimes experiences disappointments due to the lack of coordination between the engineering and sales departments of a truck company. The term “service” is often misunderstood by the purchaser and misrepresented by the salesman, which results in dissatisfied customers. Salesmen should have accurate information on the service policy of their company and on all guarantees which they are authorized to make. After rehearsing many of the difficulties encountered in truck maintenance, the author discusses in some detail the needed improvements in truck design, passing then to details of maintenance practice and methods of handling repairs.
1921-01-01
Technical Paper
210031
J C THORPE
The paper treats of the service, commercial and technical aspects of the subject in turn. The author calls attention to the fact that there can be no such thing as free service, because the customer pays in the end, and gives a specific definition of service. He argues that the engineering departments should urge upon merchandising departments intelligent distribution through dealers, the stocking of an adequate supply of parts and the maintaining of a well qualified mechanical force for the purpose of making engineering development work in the form of farm power automotive apparatus effective. There is a great need for a suitable system of training mechanics for tractor service work, and there should be a definite plan to assure that men making repairs and adjustments in the field are well qualified.
1921-01-01
Technical Paper
210027
J B HANEY
The author describes the progress of the work of artillery motorization in the year 1920, beginning this with a statement of the recommendations made by the Westervelt Board, appointed by the War Department to make a study of the subject, for the development of track-laying equipment, the use of wheeled trailers on which the track laying materiel could be loaded and towed over good roads by trucks, and in regard to the possibility of incorporating trailer wheels in the track-laying vehicles themselves. The various types of materiel constructed during 1920 are illustrated, described and commented upon, inclusive of heavy tractors, supply and maintenance equipment, gun-mounts and tanks. It is stated that the recommendations of the Westervelt Board will be the basis of armament development for some time to come.
1921-01-01
Technical Paper
210003
H M CRANE
In recent years automobile engines for racing purposes have been very generally rated in accordance with their piston displacement. The natural result has been to encourage the highest possible engine speeds to attain the greatest possible piston displacement per minute. Features of engine design that have been developed under this rule include enormous valve areas, usually obtained by a multiplicity of valves, huge inlet pipes and carbureters, extreme valve-timing and very light reciprocating parts, all of which are undesirable in commercial engines. To encourage the design of engines of a type developing higher efficiency at lower engine speeds, the suggestion is made that a rule be formulated under which cars will be rated in accordance with the piston displacement per mile actually used by them. Such a rule would involve rear-wheel diameter and gear-ratio, as well as the piston displacement of the engine.
1921-01-01
Technical Paper
210002
F W CALDWELL
It is of course impossible to consider propeller design very much in detail in a paper of this nature. It can be said, however, that the airfoil theory, in connection with the inflow theory, has given very good results and proved exceedingly valuable for the aerodynamic design of propellers. Both theories, however, in the present state of knowledge, must be applied with a number of empirical factors. Propeller-design theories and the subject of aerodynamics are discussed mathematically, as well as the elements governing the best propeller diameter for obtaining the highest thrust. Consideration is given in detail to steel, adjustable-pitch and reversible propellers as well as to those made of laminated construction consisting of sheets of paper fabric impregnated with bakelite as a binder. The mathematical considerations that apply to propellers when reversed in flight, the time and distance required to stop when landing and the propeller stresses are enumerated and commented upon.
1921-01-01
Technical Paper
210017
A L PUTNAM
As the engine is the most important unit of a complete automobile chassis, it has had a major share of attention in its development and is far in advance of the rest of the machine as a result. Consequently, at least for the passenger-car engineer, improvements in the automobile as a road vehicle offer greater scope and reward than improvements in engines, particularly as all such improvements are reflected in direct proportion instead of being minimized by adverse operating conditions. The attitude has been common of not worrying about a fraction of 1-per cent loss here and there when such an enormous loss occurs at the exhaust pipe and radiator. Other varying and intermittent losses in the aggregate are not insignificant and, when multiplied by millions of cars, become millions of gallons of fuel and oil. The author's aim is to call attention to some of these losses, with suggestions as to means and methods of correction.
Viewing 19951 to 19980 of 20059