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The development of a mathematical model of StillerSmith Mechanism for the application of a 4-cylinder plunger pump system is presented. The magnitude and direction of the internal dynamic load are obtained by solving a set of equations using the overall geometric parameters, prescribed motions, inertia distribution, and applied torques on the system. The simulation presented here yields the history of the internal loads, which are then normalized with respect to the required peak output load on the plungers, through an entire rotary cycle. The approach allows for the development of further design criteria through parametric sensitivity studies.

Continuously variable transmissions (CVTs) are usually used in small vehicles due to power limitations on the variable elements. Continuously variable power-split transmissions (CVPST) were developed in order to reduce the fraction of power passing through the variable elements [1,2]. The configuration presented in this paper includes a planetary gear train (PGT), which in combination with the CVT allows the power to be split and therefore increase the power envelope of the system. The PGT also provides a branch that can be used in a hybrid electric vehicle (HEV) operation through an electric motor. A conceptual design of a CVPST for a HEV is presented in this paper. The objectives are to show the different operational modes, with diagrams, perform a power analysis, develop the velocity and force equations and finally show the performance of the system with an example application.

The basic design of a purely rotary motion engine has potentially many advantages over the conventional piston-crank internal combustion engine. Although only one rotary engine has been successfully placed into production, rotary mechanisms still show promise in the market place. A comprehensive review of rotary engine concepts is presented with an emphasis placed on the last 30 years. Suggestions are made as to where research concentrations should be placed to improve the progress of a rotary engine.

This paper describes the strategy for engineering design, modeling, and analysis of a planetary - CVT (Continuously Variable Transmission) system. The uniqueness of this mechanism arrangement resides in the combination of features associated to two conventional systems, namely a planetary gear train and a CVT pulley system, acting as a power circulation control unit. The pulley system features a manually activated control over the variable pitch ratios of the CVT, by means of which the overall system input/output velocity and power ratios can be controlled according the operational requirements. By using the belt drive as a feedback control unit (as opposed to the main driveline), one of the major problems or limitations of conventional CVT arrangements is overcome, namely the belt capacity of the system. Specifically, the output torque obtained through the planetary output shaft is greater than the torque circulating through the pulleys.

The mechanism considered here, combines the functions of a planetary gear train and a continuously variable transmission (CVT) system, through a circulating power control unit, which results by connecting the sun-gear shaft and the ring-gear rotation through a variable pitch pulley system. The mechanism is simple and does not require clutches for its operation. Three basic configurations are presented, two of them produce a power feedback effect and a third one produces a power split forward, without a “geared neutral” condition. Parametric analysis is carried out in relation to the circulating power split feature in order to to assist in the design of an optimum configuration for light-weight applications. A parametric approach is used to generate a model that can be used to perform parametric sensitivity analysis.

A family of transmission systems based on a “Planetary Gear - CVT” mechanism is presented here. The systems considered consist of two compound planetary gear trains connected through a CVT pulley system to provide the power/torque split and recirculation function, without the use of additional clutches and/or chain drives. A two degree of freedom system results in which one of the degrees of freedom is directly related to the CVT ratio. The mechanisms considered here combine the gear reduction function of compound planetary gear trains with the continuously variable trans- used as a circulating power control unit. The kinematics and dynamics of this family of systems is presented with emphasis on the belt forces, torques on the various shafts and the overall input/output velocity ratios through the CVT ratio span. Then a parametric analysis is conducted to characterize the effect of the various functional ratios and parameters of the system in terms of the overall performance.

In this paper, a new method for the hydro-dynamic analysis of a sliding cylinder in a fully lubricated parallel track is presented. The method is an extension of Booker's “Mobility Method” (developed for cylindrical journal bearings) to the case of sliding cylinders, in which the clearance between the track and the cylinder, the viscosity of the lubricant, the radius and length of the pin, the sliding velocity and the applied transverse load determine the hydrodynamic behavior of the cylinder. In the Rand Cam™ Engine [1]*, the axicycloidal motion of vanes is driven by a rotor and a cylindrical cam, and one of the alternative designs to provide this function is based on a cylindrical pin sliding within a track which follows the profile of the motion of the main cams of the engine. This function is very important for the engine, since it separates the load bearing function from the sealing function left to the apex-like seals.

Continuously variable transmissions, commonly known as CVT's, have been shown to be feasible alternatives to the conventional multi-step gear transmissions (standard or automatic) typically used in automotive applications. Most CVT applications, however, rely on a shaft-to-shaft transmission arrangement, in which the belt-sheave action limits the load capacity of the transmission, particularly at the high power ranges (low speed, high torque). In this paper, a system based on a combined planetary gear train and a continuously variable pulley system is presented. The uniqueness of this arrangement is that the variable pulleys provide a power/torque split and recirculation function, which, when combined with the planetary gear train function, produces a continuously variable power split transmission system.

A comprehensive review of low-heat rejection engine concepts is presented. Areas examined include the materials being considered for these engines; fuels including coal; the effects of high temperature upon emissions; tribology with ceramics; exhaust heat utilization systems; and applications of these engines. Inconsistencies in the literature arc discussed.

With few exceptions most internal combustion engines use a slider-crank mechanism to convert reciprocating piston motion into a usable rotational output. One such exception is the Stiller-Smith Mechanism which utilizes a kinematic inversion of a Scotch yoke called an elliptic trammel. The device uses rigid connecting rods and a floating/eccentric gear train for motion conversion and force transmission. The mechanism exhibits advantages over the slider-crank for application in internal combustion engines in areas such as balancing, size, thermal efficiency, and low heat rejection. An overview of potential advantages of an engine utilizing the Stiller-Smith Mechanism is presented.

Continuously variable transmissions promise to improve the performance and drivability of vehicles. The design and implementation of continuously variable transmissions for medium or large displacement (power) engines have been hampered by the power limitations of the belts. A continuously variable transmission with a power split design (CVPST) has been developed to minimize the loading on the belt while providing for increased power transfer compared to existing designs. To aid in the design and development of this CVPST, a simulator program has been developed. The simulator can be used to optimize the CVPST and to compare with other transmissions. Finally, an optimized CVPST design is presented.