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This paper presents the system concepts of the Kinematic Analysis Method (KAM). The KAM system enables the design engineer to automate the analysis of a wide variety of mechanical linkages. This is the second in a series of papers from the IBM Automotive and Machine Design Group, which originated the KAM system.

An experimental computer programmed system has been developed to aid in the analysis of planar and spatial linkage mechanisms. Linkages are described to the system in a simple FORTRAN-like language. The system compiles and solves the equations, which define position, motion, and force for the linkage. The design of the system is based on concepts developed for computer aids to engineering in other fields and on recent developments of analytic methods for mechanical design. Basic requirements of any design analysis system were identified during the programming of the system.

The significance of diesel fuel physical properties with respect to fleet performance and economy has been reviewed. Relationships between certain of the key properties are discussed, and the importance of a balanced diesel fuel described.

Good gasoline mileage is a result of a carefully developed vehicle, high quality fuel, and sound maintenance. A gradual improvement in gasoline has permitted more efficient engines. Highest engine efficiency is achieved by utilizing the maximum useful compression ratio, and by meticulous tailoring of carburetors, distributors, cooling systems, and other components to each engine model. Because these components are closely matched and are subject to deterioration in service, good maintenance is a primary part of obtaining all of the gasoline mileage that was built into the fleet vehicle.

The internal combustion engine cylinder head gasket is the most complex of all gasket applications. This is due to the variety of seals and sealing conditions which must be achieved in a single gasket. Some of the physical characteristics studied for such gaskets include spring rate, stress relaxation, torque loss, and permeability of current materials and elements used in these constructions. The effects of temperature, sealing stress, thickness, geometry, and engine operation on the properties of gaskets are discussed. In one of the theoretical derivations given, a mathematical model of a viscoelastic material is used to explain the results of certain experimental testing. Major emphasis is placed on spring rate and stress relaxation, which are directly related to fluctuations of sealing pressure and loss of torque which must be controlled in order to achieve satisfactory sealing.

The cost of fuel is a major expense item for long-haul fleet operators. There are many factors which affect fuel economy. The following are reviewed in this paper: the operational requirements, the engine, the engine installation, the gearing, the driver and the maintenance procedures. Each item is discussed and specific recommendations are made on how to improve fuel economy.

The correlation of extensive engine cranking data obtained by the Coordinating Research Council (CRC) with equally extensive viscometric data obtained by ASTM has shown that the low-temperature cranking characteristics of engine oils can be predicted by two high shear viscometers, the Ferranti-Shirley and the Forced-Ball (corrected for gel viscosity). The data collected also show that the extrapolated kinematic viscosity of multigraded engine oils has little or no value in predicting the low-temperature cranking characteristics of such oils. The abilities of other viscometers to correlate with the engine cranking data are also considered.

If bearing wear is not controlled, complete axle deterioration may result from loss of preload which affects the rigidity of the gear mounting. The effect of excessive gear wear debris on hypoid axle tapered roller bearing wear and influence of various lubricants on the wear rate have been evaluated in both car and laboratory dynamometer tests. Modifying the gear geometry to eliminate high pressure areas of gear contact and selection of the optimum gear oil, as a result of these tests, have been successful in reducing bearing wear.

The need for a viscometer to accurately predict the cranking characteristics of oils in engines at low temperatures led to the development of a reciprocating viscometer. This paper describes the development of this viscometer including studies made using model aircraft engines to test the feasibility of the approach. Data are presented on various test oils to show correlation between engine viscosities determined in full scale engines and corresponding data obtained in the model aircraft engines and reciprocating viscometers. Results show that this viscometer has the ability to predict low temperature cranking properties of engine oils in full scale engines.

This paper presents a progress report on the development of low temperature viscometric techniques by ASTM Section B on Flow Properties of Non-Newtonian Fluids. These techniques are based on engine cranking studies obtained by the Coordinating Research Council. Two techniques involving three viscometers are reported.

This paper discusses the use of vector algebra to obtain the motion of elements of linkages falling within the scope of the KAM system. Both the mathematical and the programming techniques used to obtain the velocities and accelerations are discussed in detail. The procedure used results in a set of linear equations and thus provides an exact solution.

This is the third paper in a series of six papers describing the KAM (Kinematic Analysis Method) system, which is a computer oriented generalized approach to solving linkage mechanisims consisting of single or multiple series loops of one or more degrees of freedom. The generalized position solution section of KAM is described herein along with its scope and limitations

The program for force and torque analysis of planar and spatial linkages is part of the KAM (Kinematic Analysis Method) system. A general set of force and moment equilibrium equations has been developed. The program generates the parameters for the equations from a computer stored description (the plex) of a linkage and then solves the equations for all static forces and torques.

This is the sixth paper in a series of six papers describing the KAM (Kinematic Analysis Method) system being developed by the IBM Automotive and Machine Design Project. The system will be used in the analysis of most industrial linkages for which an explicit position solution exists. This paper describes the application of vector algebra to a linkage mechanism that is more complex than those classes acceptable to the KAM system. The intent here is to outline the methods developed, and their advantages, for such an application of vector algebra.

After reviewing the present state of diesel engine design art as applied to vehicle applications, the paper analyzes future application requirements and outlines possible paths of engine development. In general, future requirements demand engines of higher output, lighter weight, better fuel economy, and smoke-free operation. A better understanding of vehicle load demands and careful matching of engine and drive-line will be required. Reference to extensive recent research developments shows that the diesel engine industry will be prepared to meet this challenge to provide the customer the best possible engine in terms of return on his investment.

The purpose of this paper is to define the important considerations facing the chassis designer in selecting a power-plant for a heavy duty vehicle. An assessment of the merits and demerits of optional approaches to the problem is made. Future trends in the factors determining powerplant selection are discussed.

In spite of dominance in aircraft and serious penetration of nonvehicle industrial markets, gas turbine powerplants are found only in a very few industrial vehicles. It has been necessary to evolve sophisticated turbines to challenge diesel and gasoline reciprocators on an economic basis, since no overwhelming functional advantages can be credited to vehicle turbines (in contrast with aircraft engines). With progress in recent years, this “break-even” point has been reached in some market areas, and the next decade, with continuing increases in gas temperature and stage pressure ratios, will see a rapid broadening of the turbine-powered vehicle market.

The purpose of this paper is to project the performance and economic objectives of over-the-road powerplants in the decade of the 1970’s. The influencing factors for this projection are trends in: intercity ton miles of freight, size and weight legislation, the interstate highway system maximum legal speed laws, and operating costs of interstate carriers. These factors set the stage and establish the horizon for over-the-road vehicles of tomorrow.

Side sealing oil rings and valve guide seals are keeping oil economy at a satisfactory level in contemporary passenger car engines. Barrel face compression ring designs show improvement in oil and blowby control over traditional configurations. Metallized molybdenum coated compression rings offer improved ring life where chromium plate scuffing is present. Chromium plate, though, is still unsurpassed for abrasive wear resistance. A new technique, using sonic energy for measuring ring conformability, is being used for research and development. A high magnification automatic ring face contour gage allows better production control and more accurate experimental ring evaluation.

Passenger car engine poppet valves operate in a critical temperature range by virtue of their function and environment. Certain engine design parameters such as the shape of the valve head, cylinder head valve layout, stem-guide relationship, fuel-air ratio, and compression ratio exert a direct influence on their temperature and performance. In operation, abnormal combustion phenomena may further increase the normally high valve temperature. This paper describes the effect of these factors on valve temperature.