Search Results

The U. S. Customs Service is working through international organizations to further its policy of facilitating the flow of cargo in international trade while interdicting the movement of contraband. These organizations, with United States participation, seek to harmonize customs procedures worldwide by developing international conventions and preparing recommendations to member states. The Service is also moving toward an automated merchandise processing system and is adapting its procedures to rapid technological advances in land and water transportation in the fields of containerization and the movement of cargo by lighters carried aboard seagoing vessels.

Containerization was the first step in a globally standardized physical distribution system. It precipitated a system of intermodal unit loads and modular packaging dimensions known as “Total Pack.” As part of this system, reasons are presented why the air-cargo mode should adopt an intermodal unit-load 54.00 × 45.00 in (1372 × 1143 mm). Usage of intermodal and interline containers is traced through the entire distribution system, including solutions to key problems.

The objective of the study was to estimate and explore the potential for reducing the costs of new urban mass transportation systems. The significance of major components of the capital investment cost was determined for guideway systems. Specific methods of reducing the cost of the most significant components were identified and examined in detail. These methods are (1) economies of scale in construction, (2) reductions in the requirement for guideways by utilizing a dual-mode vehicle, (3) eliminating tunnels by using super-elevated guideways, (4) new tunneling, (5) joint purchase of vehicles by several systems, and (6) reductions in initial vehicle purchases by reductions in the maintenance float. Three major conclusions were reached in this paper. First, there appears to be no opportunity to dramatically reduce the cost of urban transportation. All potential reductions are on the order of 5 to 10 percent.

Existing transit services in the Washington, D.C. area are faced with increasing costs and diminishing patronage, resulting in declining service. Top priority tasks are to provide for the improvement of existing bus services, planning for integrated and efficient bus operation before, during and after construction of the rail rapid transit system; and initiation of new and expanded passenger and service improvements. Future transit planning must recognize, however, that land use and travel patterns dictate the choice of travel mode. In fact, highway improvements will also be required in order to serve the land development and travel generated by the transit lines themselves.

Valence or bumper filler panels as well as other exterior automotive body components of painted elastomers have been used and are being considered more extensively for future models. Three types of materials are the prime candidates: EPDM rubber and thermoplastic or thermoset urethanes. The parts, however, must perform adequately within the automotive design criteria framework of MVSS regulations, cost, fabrication, appearance, and style.

A study was made of details of friction characteristics of several kinds of clutch-facing materials of resin mold type. With particular attention given to the low-speed slip area, the following was made clear: There exists a thin film on the friction surfaces of facing and mating materials. A thin film is presumed to be a visco-elastic substance which is susceptible to momentum and affects, to a great extent, friction and wear characteristics.

This paper discusses how to turn a 3-point inertia belt into a passive seat-belt system. The main objectives of the program were to prove that it would be possible to use existing seatbelt systems to cope with future requirements for occupant restraints and that therefore existing anchor points (or at least the existing systems) could be used. The aim was to use only existing techniques in order to reach a high reliability standard and to design a system that also could meet current homologation requirements. A prototype was developed with a combination of a 3-point seat belt with running loop with an inertia reel at the central lap belt, in combination with loops around the webbing of the seat belt running along cable-operated tracks. The prototype met all the objectives.

A simple model of the engagement process for paper friction materials has been conceived, consisting of squeeze film, squash film, and adhesive contact phases. In support of the model, laboratory test results are presented of paper clutch squeeze and squash film behavior in a new laboratory test fixture. Also scanning electron microscope photographs, profilometer data, and clutch inertia dynamometer friction and wear results are discussed in the context of the new engagement model.

This paper presents a summary of studies initiated by the British Technical Council to examine the repeatability and reproducibility of cold crank simulator results obtained on European cross-graded engine oils used in gasoline and diesel engines, and also to relate the results obtained to actual cranking speeds. The study of various components of engine cranking resistance on low-temperature starting behavior confirms that only those having oil viscosity dependence are related to temperature. Results obtained on engine startability and the cranking of used lubricants show significant increases in cranking speed as a result of fuel dilution, but show the converse for high insoluble contents (up to 10%). An advantage in cold startability is shown for the low end of the 20W specification compared to the high, but magnitude depends very much on the individual engine.

There are numerous engineering solutions to the energy management problem in low-speed vehicle bumper impact situations. This paper covers a North American Rockwell volute spring energy storage assembly. Selection of a system involves price, performance, installation, weatherability, reliability, etc. Extensive tests-pendulum corner impact, barrier, and pendulum-were carried out and showed that the volute spring assembly on a test vehicle withstood more than 100 impacts without evidence of failure.

The choice of material for a particular application depends on many factors, including cost, availability, appearance, strength, fabricability, and corrosion resistance. Frequently, use of a monolithic metal is compromised by one or more of its properties. The metallurgical materials systems concept provides a means of designing specific properties into a single composite material. Two or more metals are bonded at the atomic level to form a clad metal that meets the precise requirements of a specific application. In this report technical factors involved in designing corrosion-resistance materials systems are considered. Advantages and limitations are discussed and specific automotive engineering applications are used.

The electrochemical action of stainless steel trim in direct electrical contact with auto body steel can promote accelerated rusting of body steel in crevices where paint may be defective or damaged. Rain, snow, and/or road splash containing deicing salts and other contaminants provide the electrolyte. A dissimilar metal battery is created under such conditions resulting in the less noble body steel undergoing rapid galvanic attack. Attempts to prevent this type of corrosion have been investigated in the laboratory and by actual service testing. The various methods evaluated included electrical insulation to interrupt the flow of galvanic currents and the use of a third sacrificial metal which would provide cathodic protection. Among the many third metal systems tested, the aluminum striping concept was proved to be the most practical as well as the most effective for suppressing objectionable galvanic rust of autobody steel.

Automotive emphasis on reliability and reduced warranty costs is opening up new concepts in printed circuit switches. The economy of using a printed circuit board to provide electrical interconnections between circuits also provides consistency in high production, reduces labor, and the number of manufacturing operations. The printed circuit board approach offers the creative design engineer increased freedom in design approach since the printed circuit board is a structural member as well as an insulator with selective electrical circuitry. It is possible to use the printed circuit for contacts and minimize the number of electrical interfaces; however, each design must be evaluated on an individual basis. Printed circuit switches also offer an extension of printed circuit connector technology, connecting directly to the printed circuit board. Printed circuit connectors are easily attached on assembly line for fast, reliable electrical connections.

Hard back printed circuit switches, also known as on-circuit switches, offer an opportunity for switch designs which are reduced in complexity and enhanced in reliability in single switch mode concepts. On-circuit switching also offers the opportunity for the consolidation of two or more switching modes into one assembly which can have reliability, cost, convenience, and styling advantages; as well as leading to simplification of connecting wiring harnesses. While having the advantages noted, the on-circuit switching concept also has limitations. Failure of the printed circuit due to mechanical wear and/or electrical erosion is a major concern. Careful selection of switching modes must be made so that electrical load and endurance requirements do not exceed the ability of the device. The Achilles Heel of the concept is at the interface between the movable switch contact and the stationary contact, which is integral with the printed circuit board.

In 1972 models for sale in California, Buick first employed programmed-metered exhaust gas dilution of the engine intake charge as the major means of reducing Oxides of Nitrogen (NOx) emission levels. With more stringent NOx emission standards applicable nationally to 1973 light duty vehicles, it is probable that similar systems will be more widely used. The major considerations in the decision to use this means of reducing NOx emissions, the design details of the total system, and the field experience to date is discussed. The author concludes with some thought on the limit of usefulness of Exhaust Gas Recirculation for NOx reduction, and further refinements needed to approach that limit.

The first attempts in corrosion preventative maintenance in vehicle bodies came about in the early Sixties. Air Force TO 36-1-5, Army TM 38-600, Post Office V-5-65 and NAV DOCKS P-300 were quite general in their descriptions and defined areas on the vehicle to be rustproofed. The material applied and geographical areas requiring rustproofing were general as well. The first materials used were proprietary in some cases; specifications in others. Currently, MIL-STD-1223M is used to specify rustproofing at the time of procurement rather than after the vehicle has arrived at the point of use.

Performance of packed bed type catalytic converters in controlling hydrocarbon (HC)-carbon monoxide (CO) mass emissions is investigated using a one-dimensional plug flow math model. Converter operation is explained, and the effects that some gas stream conditions and basic parameter values have on converter emission control performance during warmup are evaluated. It is shown that total mass emissions passed by the converter during warmup can be minimized by maintaining gas mass flow and HC-CO concentrations at low values. Converter warmup performance is highly sensitive to changes in bead diameter and catalyst kinetics, but it is relatively insensitive to changes in bed area/length ratio and bed void fraction. New information is presented dealing with the modeling of platinum kinetics, bead temperature stability, and mass and heat transfer j-factors for packed beds.

Because of low nitrogen oxide emissions, a version of the Renault R17 TS equipped with a high-performance engine was selected for the American market. This paper discusses problems encountered in adapting a Bosch electronic fuel injection system to a 1600 cm3 engine to meet American standards up to 1974. The principal problems solved were those posed by intermediary operating speeds. This study also gives an idea of the pollution limits which can be obtained with an injection system which incorporates various important adjustment factors. Engine specifications are presented, as are decriptions of the electric regulation, electric and pneumatic cold-start, and fuel feeding circuits. The various modifications to the engine are also described.

The automobile industry places a major emphasis on reducing car interior noise levels to attain a more pleasant and comfortable ride. In recent years, improved superhighways, allowing higher car speeds, have created a rise in the aspiration wind noise due to high aerodynamic pressure differentials causing air to pass by the body seals. No longer is a car body sealed merely against water leaks. With the increased use of air conditioning in cars, the closed side windows have lowered the ambient interior noise, thereby exposing the broad band frequency aspiration wind noise. A need for an objective method for the quality control and development of body seals was imminent. This report analyzes the aspiration wind noise parameters and presents two objective methods of measuring aspiration wind noise. These methods, using a meter, replace the previously used method of subjective evaluation of the loudness of wind noise.

In its treatment of acoustical leaks in passenger car bodies, this paper considers the general principle of noise control in a passenger compartment, the concept of acoustical leaks, examples of such leaks, and design guidelines for acoustical isolation. The paper states that the basic problems can actually be designed into vehicles through lack of understanding of acoustical principle, and various examples are given in illustration. Remedies for some of these deficiences are also proposed. Finally, design principles formulated to eliminate acoustic leaks are presented.