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Thermosetting liquid urethanes processed by reaction injection molding (RIM) can be reinforced with glass fibers. Special considerations of both the materials and the process system elements are required due to the characteristics of the reinforcement. Typically, slurries are prepared with milled glass fibers and one or both of the liquid urethane components. Then the urethane components are combined with mechanical and/or impingement mixing and injected into a mold. The resulting composites show increased stiffness and reduced thermal expansion due to the glass fiber reinforcement. These new material systems are expected to be used in many applications requiring good dimensional stability over a wide temperature range.

Sheet molding compound (SMC) has been used for functional or fascia automotive parts such as front and rear panels for several years. When properly formulated, processed, and molded, SMC has a potentially substantial role in the manufacture of more structurally demanding automotive parts. Through variations in the materials, equipment and processing techniques, different types of SMC can be produced. These are random fiber SMC (SMC-R); continuous fiber SMC (SMC-C); and directional fiber SMC (SMC-D). Representative formulations show how static mechanical properties are dependent upon glass content, glass orientation, and on the test temperature. Based on equivalent performance, these systems are lighter in weight than steel and are generally less costly, on a material basis, than aluminum.

The addition of a high molecular weight Silicone Fluid to most thermoplastics results in numerous processing advantages and cost savings. These fluids are mechanically blended with the resin melt to form stable polyblends. Addition to injection molding equipment or extruders can be accomplished either by utilizing a small metering pump or adding the fluid in a pelletized concentrate form similar to color concentrates. Excellent dispersion of the fluid in the resin results when done properly by either method. The fluid remains in the molded or extruded part in the form of small cells or droplets 2 - 4μ in size. The fluid exhibits no tendency to migrate or bleed. Fabricated parts may be decorated without the need for part cleanup.

This paper investigates the dynamic response characteristics of multilayer panels containing polyurethane foam layers. Results of driving point impedance tests on multilayer beam and circular plate structures in the frequency range 200hz - 3khz are compared with corresponding results obtained using commercial damping coatings. It is shown that configurations consisting of metal and solid polymer facings with foam cores exhibit highly attenuated response at selected frequencies. The hypothesis that the layered foam configuration acts as a dynamic vibration absorber is confirmed using a mathematical model of a sandwich beam which permits transverse deformation of the core.

Reduction in vehicle weight is a key goal for today's automobile design. This is being accomplished, in part, by replacement of metal components with lighter weight, multifunctional engineering plastics and composites. Additional weight reduction potential exists, however, through the use of high performance plastic parts from aramid and polyimide resins. The weight reducing value attributable to parts from these materials emanates from their high performance properties, and not necessarily their light weight. Superior properties allow the aramid and polyimide parts to be used in applications involving bearing loads, moving contact speeds and temperatures found too severe for other plastics. The principal benefit of their use is the designer's ability to downsize companion metal parts and to more readily incorporate lightweight metals such as aluminum.

During the last decade Powder Forging, a technique by which very precise components of high mechanical integrity and requiring minimal machining can be produced, has been the subject of intensive development activity. Powder Forging has now reached maturity; many parts are in volume commercial production, and all indications are that growth prospects are excellent. Users of parts are becoming increasingly aware of the machining, labour, investment and energy savings that can arise from adoption of the process. GKN Forgings Limited now has about thirty parts in commercial production, and a new self-contained operating Company has been established devoted entirely to Powder Forging. The paper reviews the current status of Powder Forging and describes by reference to actual components the economic and technical factors that dictate the types of parts that are best suited to manufacture by this method. Future growth predictions for Powder Forgings are discussed.

Automobile panels are stiffened in a variety of ways to meet engineering design criteria. Current example panels are numerous and include the roof, deck lid, hood, floor pan, etc. If lightweight, low modulus materials (e.g., aluminum, sheet molding compound) are to be considered for automobile panels, it can be anticipated that some form of stiffening will be necessary. In this paper, one particular type of stiffened panel, a two-layer panel consisting of a trapezoidally corrugated plate and a flat plate fastened together, is examined analytically and experimentally. A technique for modeling the panel with finite elements is developed. Rather than assigning “smeared-out” properties to the stiffeners, the fidelity of the panel is retained by modeling it as a double-layer structure (instead of as a plate) so that local deformations are also allowed.

An easy-to-use pre-processor system through which finite element analysis can be applied to routine design works is needed. We have developed a general purpose pre-processor system to be used for body structures and a number of other automobile parts. It can apply to shell, beams and/or solid structures, and has functions to generate input data, to check structures by drawing and to calculate the section constants of beam elements. It has become possible to discuss the detail design of structures because we could obtain a fine mesh models easily from complicated structures such as a automobile body.

The moving baseline of conventional engines and passenger cars utilizing such engines in the period 1975-1985 is developed from a review of recent trends in vehicle design and conventional engine and transmission development. The moving baseline is given in terms of engine specific weight and volume and vehicle fuel economy and energy intensity on both the EPA urban and highway cycles. Recent advances in conventional engine and vehicle design have lead to significant improvements in all the baseline areas. These improvements are discussed quantitatively in the paper.

Recent improvements in digital microprocessor hardware have given impetus to synthesizing a consistent set of central-processor engine-system control laws. As an approach to the problem, algorithms for control of airflow, EGR and spark advance were postulated, considering interactions of engine torque, fuel consumption, exhaust emissions, cold-starting and driveability. Development of an analog, real-time driver/vehicle model provided appropriate transient vehicle loads to the experimental engine/transmission/digital controller implementation throughout cold-start vehicular driving cycles. A Transient System Optimization procedure applied continuously over the federal urban driving schedule, including cold start, validated the postulated control laws.

This paper describes a new 6 cylinder, inline diesel which has been developed to power medium sized trucks and for industrial applications and which is currently in monthly production of 2,000 units. The engine is characterized by the use of direct fuel injection system, square toroidal combustion chamber, glow plug as a starting aid, thin dry chrome plated cylinder liners, engine stop system using air shutter, and newly-developed variable speed RLD-K governor with torque control cam, all of which are discussed here from aspects of design and experiment. Also covered are family engine concept and emission and noise control approaches.

In order to properly evaluate the consequences of replacing conventional Otto-cycle engines with alternate power systems, comparisons must be carried out at the vehicle level with functionally equivalent cars. This paper presents the development and application of a procedure for establishing equivalent vehicles. A systematic weight propagation methodology, based on detailed weight breakdowns and influence factors, yields the vehicle weight impacts due to changes in engine weight and power. Performance-matching criteria, utilizing a vehicle simulation program, are then employed to establish Otto-engine-equivalent vehicles, whose characteristics can form the basis for alternative engine evaluations.

This paper on disc brakes for passenger cars with incorporated automatically adjusted handbrake mechanisms traces the way in which the experience with various alternative Girling adjuster systems is leading to recommended design- and development parameters for such devices.

The brakes are applied automatically at the time of any system failure. The parking brake is operated by the parking/emergency switch on the dash panel or the ignition switch, without physical effort as found in the conventional hydraulic brake systems. Full-power parking/emergency brakes and fail-safe concepts have been accomplished in the straight-air brake systems. However, duplication of these systems to hydraulic brake systems incurred some difficulties due to the physical properties of fluid, and it is generally concluded that the parking/emergency brakes must be mechanical brakes, and the hydraulic pressure should not be maintained for extended periods of time. The electro-mechanical method employing a detent system is a breakthrough in restraining spring force during normal operation.

Duhamel's theorem is used to integrate an analytical slab solution with a nodal solution to utilize the advantages of each method. The analytical part of the model provides a detailed temperature distribution through the rotor rims which is used to estimate the rim thermal stresses. Experimental results are used to derive a model of the vent cooling. Brake dynamometer tests are compared to the calculated results to verify the model. Some examples of parameter variations are given that show typical model capabilities.

This paper gives analytical expansion to the possibilities facing a designer when dealing with detail design problems of the Girling Colette caliper. A feature of this caliper is the flexibility with which it can be tuned to encompass the total requirements of the installation.

Our institute, J.A.R I., has built a new wind tunnel to accommodate full-sized vehicles. Various newly developed ideas were incorporated in this facility, which, nearly 100 m long, is of Eiffel type with two test sections arranged lengthwise that can be used simultaneously and efficiently. Wind velocity ranges from 2.5 to 57 m/s in the first test section, which is 3 m (H)x4 m(W)x10 m(L). In the second test section, which is 5 m(H)x6 m(W)x13 m (L), the wind velocity ranges from 1 to 23 m/s. The facility enables a wide range of aerodynamic experiments to be conducted with 1/5 scale models up to full-sized passenger cars in the first test section, as well as with heavy duty trucks and buses in the second test section.

Primary design factors with regard to outside mirrors are curvature, size and spatial localization. Experiments were conducted to find the effects of these factors in relation to visibility and the size of field of view. Investigations to determine visibility requirements were static testing and field testing. The results show that convex mirrors with 47 inch radius of curvature are most preferable for the visibility requirements. Required size of field of view was established taking into account the size of direct field, vehicle size and lateral distance to another car.

The concept of interoperability is based upon standardization of combat vehicles at the subsystem level. Past attempts at international system level development have been frustrated by such factors as a diversity of design philosophy, deployment schedules, production unit cost, and an economic need to maintain commonality with existing national fleets. The logistics potential of common equipment has resulted in renewed interest concerning the use of standardized components. In addition, the heretofore unaddressed area of common crew/equipment interfaces is being investigated. Through careful attention to human factors, a measure of system level standardization may be attained.

Performance and exhaust emissions of five unthrottled open-chamber stratified charge engine designs are compared on an equivalent basis, to illustrate the effects of the different strategies used to mix the fuel and air and to provide data useful for those currently engaged in stratified charge engine development.