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The objective of this work is to generate a robust slipping-clutch model that will be employed as a component for driveline dynamic simulations. The model was mainly focused on the relatively detailed slipping-clutch interface temperature evaluation. The core reason for including interface temperature computation is to better estimate the dynamic coefficient of friction. The contribution of this work is in the development of a simplified close-form approach to solve the thermal field problem at the clutch interface. Compared with implicit numerical methods (such as the finite difference method), the close-form approach reduces the computational cost significantly. In addition, this model can be embedded in commercially available simulation software (such as MATLAB1 and EASY52) without the need to consider the numerical integration methods, which generally are a concern when implicit numerical methods are used.

Driveline vibration is usually associated with friction clutch dynamics. However, the roller One-Way Clutch (OWC) can also be a source of vibration. The OWC has two basic operational modes: 1) Engaged, and 2) Freewheel. In this paper we will develop a means to predict the freewheel-mode resonant response of a roller OWC system. The study begins by making some fundamental simplifying assumptions, which lead us to an equivalent OWC system spring rate, kowc. The roller OWC system is then modeled as a simple mass-spring-mass system, from which the application of appropriate boundary conditions yield the desired fundamental resonant frequencies. This analysis method is then applied to a number of roller OWC systems, and the results are compared to numerical simulation and experimental results.

In 1997, Chesney and Kremer wrote a paper entitled Generalized Equations for Roller One-Way Clutch Analysis and Design [1]. The paper explained both the static and dynamic behavior of roller One-Way Clutches (OWC), and described the practical application of esoteric stress equations to the design of roller OWCs. This paper offers a similar analysis of another member of the one-way clutch family, namely Sprag one-way clutches. Sprag one-way clutches are clutches that freewheel in one direction, but transmit torque due to the geometry of the sprag, when the races are rotated in the opposite relative direction. Specifically, the paper discusses the theory of operation, equilibrium equations, system deflections, system stresses, and dynamic behavior of a sprag one-way clutch. The paper derives and explains the fundamental equations in terms of dimensionless units, in order to enable the use of either English or metric units.

In 1973, Sauzedde [1] wrote a paper that is commonly considered the benchmark document on roller One-Way Clutch (OWC) analysis and design. Among other topics, Sauzedde led the reader through analyses on contact stress, outer ring hoop stress, and roller centrifugal force computations. Following this seminal paper, several enhancements were presented, further refining the original equations [2] and better describing roller mechanics [3]. At the time these papers were written, the automotive industry in the U.S. predominantly used the English system of measure. The use of English units often obscured the original derivations of constants used in the equations. The purpose of this paper is to present the equations used in roller OWC analysis and design in terms of dimensionless units.

One-way clutch performance is dependent on its mating races. If a race fails, the clutch fails. Accurate structural analysis of the race is necessary to expedite the clutch system design. Several equations are available for this purpose. Sauzedde [1] presented hoop stress equations for the outer race based on the work of Timoshenko [2]. The objective of this work is to verify the results of these stress equations. This will be accomplished by comparing the stress results from a series of finite element analysis models to the results of the equations. Good agreement between the two methods has been found.

A condition which directly influences the dynamic performance of the roller clutch is roller float. Roller float is defined as a condition where the roller loses contact with the roller-way. Runout of the roller-way can create this condition. When the over-running speed of the inner race is high enough and the roller-way runout great enough, the roller inertia force will be of sufficient magnitude to overcome the spring force. To investigate this condition the method of kinematic equivalence is employed. The analytical results indicate the potential hazards of excessive raceway runout, and these results are supported with experimental evidence.