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1923-01-01
Technical Paper
230037
C P GRIMES
The author believes that the universal power unit will be direct air-cooled, but states that the direct air-cooled engine is now in the minority because, until very recently, there has not been a sufficiently broad series of established engineering facts and development work available to form a foundation for improvement. The satisfactory air-cooling of an 8 x 10-in. cylinder has been reported, and the development in a smaller cylinder of 138 lb. per sq. in. brake mean effective pressure; also, in a three-cylinder, air-cooled, radial-engine, a brake mean effective pressure of more than 125 lb. per sq. in. was developed and the engine endured beyond the ordinary expectations for water-cooled engines.
1923-01-01
Technical Paper
230012
E H LOCKWOOD
Annual Meeting Paper - The heat-dissipating properties of three types of radiator core have been investigated at the Mason Laboratory, Yale University. These include the fin-and-tube, the ribbon and the air-tube groups, so classified according to the flow of the water and the air. The ratio of the cooling surface to the volume is shown to be nearly the same in the fin-and-tube and the air-tube cores, while that of the ribbon core is somewhat greater. A formula is derived for computing the heat-transfer coefficient, which is defined as the number of heat units per hour that will pass from one square foot of surface per degree of temperature-difference between the air and the water and is the key to radiator performance, as by it almost any desired information can be obtained. When the heat-transfer coefficients have been found for a sufficiently wide range of water and air-flows the cooling capacity of a radiator can be computed for any desired condition.
1923-01-01
Technical Paper
230017
S VON AMMON
A record of an investigation of heavy-duty truck-axles carried out by the Bureau of Standards at the request of the motor transport division of the Quartermaster Corps, this paper deals in particular with the mechanical efficiency of the axles tested. The investigation included, in addition to several worm-drive Class-B Army-truck axles with different types of bearing, a number of axles usually designated respectively as “internal-gear” and “multiple-reduction” type. Each of these types was represented by axles in successful use in commercial trucks of 5-ton rating. In analyzing the results of the tests it was found possible to separate the losses into no-load losses and load losses; the total loss being the sum of these two. In general, the no-load losses were primarily controlled by the viscosity and the method of application of the lubricant. They were greater in those axles in which the parts rotating at high speeds were immersed most completely in the lubricant.
1923-01-01
Technical Paper
230048
F H FORD
Instead of representing light intensity by lines to indicate photometric values the author recommends an arrangement for denoting the intensity by varying degrees of tint on the surface of a chart that is supposed to represent the roadway. In the opening paragraph the thought is brought out that present-day automobile lighting-equipment is not designed in such a way as to make its performance a selling feature and the several reasons why the efficient distribution of light on the road has been overlooked are pointed out, emphasis being laid on the fact that the average car-designer is not an illuminating engineer, and that even if he did wish to use the best light available on the car he would have to make personal tests of the devices under all conditions of night driving before being in a position to recommend the most efficient head-lighting device.
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
230043
E FAVARY
The five types of final-drive now in use on motor vehicles are stated by the author to be (a) the chain-and-sprocket, (b) the bevel-gear, (c) the worm-gear, (d) the double-reduction and (e) the internal-gear. The advantages of each type as emphasized by its maker are presented and commented upon, and the same procedure is followed with reference to their disadvantages. Following these comparisons of the different drives, which cover about the first third of the paper, the bearing loads and shaft stresses of typical semi-floating and full-floating axles are calculated for the conditions (a) maximum torque plus the normal radial-load on the wheel, (b) the wheel locked and skidding forward when the brakes are applied and (c) the wheel skidding sidewise while the truck is moving. A tabulation of the results obtained from the mathematical calculations is included.
1923-01-01
Technical Paper
230041
Malcolm Loughead
ABSTRACT
1923-01-01
Technical Paper
230016
L VALENTINE PULSIFER
Annual Meeting and Detroit Section Paper - As the success or failure of the finish of an automobile depends largely on the finishing-varnish, a plea is made for more scientific analyses of the problems of automobile finishing and more care in selecting and applying a suitable varnish. The qualities to be desired in a finishing-varnish are divided into two classes: the shop qualities and the service qualities. The shop qualities include color, body or viscosity, working, flowing, setting, hardening, fullness and the safety of working. The service qualities, or those that enable the varnish to withstand the various conditions of use, include resistance to break-down under the chemical action of the actinic rays of sunlight, to the destructive action of moisture and the alkalis in mud and soap, to expansion and contraction, to vibration and to abrasion.
1923-01-01
Technical Paper
230011
S D HERON
Stating that most of the copying of aircraft practice in post-war car-design has proved a failure because the fundamental difference in duty has not been realized, the author proposes to show wherein the automobile designer and the engine builder can profit by the use of practice developed for air-cooled aircraft engines and, after generalizing on the main considerations involved, discourses on the simplicity of layout of the efficient air-cooled cylinder as a preface to a somewhat detailed discussion regarding cylinder design and performance, inclusive of valve location, type of finning and form of cylinder-head.
1923-01-01
Technical Paper
230013
HERBERT CHASE
Stating that automotive literature presents surprisingly little helpful information concerning the faults of the steering-systems used on automotive vehicles and that, in spite of the fact that so many of the faults are self-evident, they frequently are overlooked in actual practice, the author includes with the presentation of his own investigations summaries of the views expressed by numerous well-qualified automotive engineers and discusses these steering-gear faults in some detail. Beginning with the subject of safety, consideration is given successively to the causes of hard steering, the angular position of knuckle-pivots, knuckle-pivot location, the foregather or toe-in of wheels, castering or trailing effect, wheel-wabble, drag-link location, irreversibility, steering-gear type comparisons, tie-rods and tie-rod arms.
1923-01-01
Technical Paper
230047
J E HALE
THE author describes the results of a deliberate attempt to make motor vehicles ride on air that is at a low pressure, through the usage of an air-cushion tire having greater carcass flexibility than is usual and by enlarging the size of the tire section so as to provide a greater area of contact between the tire and the pavement. The goal tried for was to increase the area of contact sufficiently so that air pressures ranging from 20 to 35 lb. per sq. in. could be employed in actual practice. Fundamental conditions are considered first, followed by statements as to what advantages the air-cushion tires containing air at low pressure give to a car. The effects on car operation are presented at some length, inclusive of considerations regarding car speed, steering ability, front-wheel shimmy, traction, braking control, blow-outs, side-sway, and other factors of influence.
1923-01-01
Technical Paper
230029
E P Warner
The author discusses commercial-airplane design in general terms, considering the subject under the main divisions of economy, safety, speed and comfort. Under economy, mention is made of possible reductions of first cost by designing for long life and reliability, the effect of the former on the depreciation allowance being obviously advantageous. Airplane size is debated also, the trend of progress being seemingly toward the giant airplane. Safety is stated to be dependent upon reliability, structural strength, stability, control, fire prevention and reduction of risk of injury to passengers in the event of a crash. Minimizing the results of a crash is considered suggestively. Speed is governed almost solely by the ratio of wing loading to power loading; hence, speed will always be kept as low as possible without loss of business to competing transportation enterprises. Included among desirable measures to secure comfort are adequate ventilation and the elimination of noise.
1923-01-01
Technical Paper
230052
H. P HARRISON
To install conveyors in a going automobile manufacturing plant of moderate size, without interrupting production, and with a minimum amount of rearrangement of the plant and an investment commensurate with the saving to be effected, was the problem, the solution of which is herein described. The conditions that determined whether power-driven or gravity-actuated conveyors should be used are discussed and the various types required for handling raw stock, for machining operations, for sub-assemblies and for finished assemblies are indicated.
1923-01-01
Technical Paper
230049
OSCAR A KNIGHT
In production grinding the progress made during the past few years has been along the line of grinding multiple parts simultaneously, such as piston-rings, ball and roller-bearing cups and so forth. This kind of grinding brought about the use of wider wheels to cover the entire surface of the work, whereas formerly narrow wheels had been used with the traversing table method. With the development of these operations came the cylindrical grinding of square and distributor cams; also square shafts, using the oscillating cam-grinding attachments; piston-relief grinding with the same attachments; and two-wheel or double-wheel grinding for such parts as steering-knuckles and pinion shafts of different diameters or where two diameters are separated by some protrusion, as in steeringgear worm-shafts.
1923-01-01
Technical Paper
230028
B G LEIGHTON
1923-01-01
Technical Paper
230046
John F Duby
Since accurate wheel-alignment is of much greater importance than has been realized generally and because so much confusion existed regarding proper methods of securing it, the author explains a method for obtaining correct alignment that will insure easy steering and cause the least amount of tire wear. Correct wheel-alignment is defined and the differences between front-wheel and rear-wheel alignment-requirements are stated. “Toe-in” and “camber” are analyzed, their requisite values are discussed and the manner of determining them is explained. Axle-tilt and wheel-wabble are considered also in their relation to the subject, and a summary is given of the proper procedure to secure correct wheel-alignment.
1923-01-01
Technical Paper
230053
A F SHORE
A statement is made of nine items suggested by the Iron and Steel Division of the Society for consideration with reference to securing greater uniformity in practice when making precision hardness-tests with the scleroscope. Plumbness of the instrument is an important factor and lateral vibrations have a bad effect; these are discussed and surface smoothness of the test-specimen is considered in relation to its effect on accuracy. Other factors treated are the influence of metal-scale on scleroscope readings, the condition of the hammer diamond, and the effect of the mass of the test-specimen. Extreme under-weight specimens, inert and over-weight masses, the effect of hardness on mass and the effect of thickness of the test-specimen receive consideration, together with points concerning testing near test-specimen edges, the effect of curved surfaces and how test-specimens are held. A lengthy comparison between Brinell and scleroscope hardness-testing is made.
1923-01-01
Technical Paper
230033
H L HORNING
Since the detonation tendency of the fuel is the limiting factor in the development of power and the efficiency with which the fuel can be burned, the author considers this phase of the subject with the idea of laying down the principles on which better economy can be attained through higher compression. The subject is discussed in regard to the causes of detonation and the methods of controlling them because detonation limits the compression at which an engine can run. The phenomenon of detonation is analyzed, the author's opinion being that increasing the temperature causes an increasing frequency of radiant-energy impulses and that, finally, it reaches a point where the frequency corresponds with the critical rate of the electrons that bind the elements together; thus, it breaks them asunder and then the velocity attains the highest rate possible in a gas of that density and temperature.
1923-01-01
Technical Paper
230026
J F MURPHY
The author describes a system of automotive transportation for intra-city hauling and the moving of merchandise between railroad terminals that has enabled the company he represents to serve the city of St. Louis and the railroad terminals there with a high degree of efficiency through the utilization of tractor and semi-trailer units and a thorough supervision of their movements. The units are described and illustrated, and the conditions governing their usage are set forth. The salient features of the paper include discussions of the necessity for adequate terminals, off-track versus on-track railroad depots, the volume of tonnage, tractor and semi-trailer operation and methods of procedure and control, weight and protection of loads, haulage distance, economy and a specific statement of the principal advantages gained through the use of automotive equipment of the type described.
1922-01-01
Technical Paper
220057
A J BAKER
1922-01-01
Technical Paper
220065
C N MONTEITH
The author presents, in outline only, the various features of airplane-development investigation that have been prosecuted. After mentioning the principal types of airplane designed and built shortly before the armistice and the types in service on the battle front at that time, four specific requirements for increasing the speed, the rate of climb and the ability to reach great altitudes are enumerated and commented upon, the further statement being made that an increase in performance can result from any one or from a combination of all four. Remarks upon design features are interspersed with the discussion of performance improvements, brief explanations being given of the variable-area and the variable-camber-wing schemes, the idea of having a thick wing-section with trailing and leading edges hinged, and that of modifying the wing-section by making the leading edge a small detachable airfoil that can be shifted.
1922-01-01
Technical Paper
220064
Edward P Warner
Aerodynamic analysis relates mainly to questions of performance and stability, the latter including both maneuverability and control, but the designer's problems concern chiefly the prediction of the best possible performance. Accurate analysis, which would include a summation of the elemental resistances of an aircraft part by part and the making of many corrections, supplemented by tests of models in a wind-tunnel, involves much labor and expense. When a preliminary choice of dimensions and specifications for a new type of an airplane is to be made or there is a question of the performance attainable with a given load and power, a shorter method becomes necessary. This is to be found in the derivation of simplified formulas and graphs.
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.

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