PREFACE

This book is written chiefly for the mechanical engineer who is involved in one way or another with electromechanical components. In the last 15 years or so the two main disciplines of electrical and mechanical engineering have become more closely linked than ever before. This marriage has provided many bonuses in form of greater flexibility of design, longer service with less maintenance, cost reduction, and other benefits. These benefits are especially heartwarming to those engineers who are designing, producing, maintaining, specifying, or even studying ways and means to bring about improvements in their own or their company's fields of professional and industrial endeavor.
This growth electromechanical components, however, has not been accompanied by any widely published information and technical reference data that is both integrated and coherent. It is true, of corse, that many technical society papers and magazine articles on various phases of the subject have appeared from time to time. Also, manufacturers' literature has always been available for specific components. But nowhere is there a readily available book for an engineer who wishes to orientate himself in this rapidly growing field and avail himself of factual engineering reference data. Even engineering handbooks that are otherwise quite inclusive tend to have a blind spot for this important area. This book is written to provide comprehensive engineering information and technical data for any engineer who is involved, one way or another, in the general spectrum of electromechanical components.
I should like to define the boundaries of this coverage: the term electromechanical has tended to be applied to many devices that are actually electronic-mechanical rather than electrical-mechanical. Computers, recorders, plotting devices, metering, electronic control, and other similar areas of electronics and cybernetics are not dealt with here, since it is felt that those ares are more in the domain of the electronics engineer than the mechanical engineer.
Included here is the basic "bread-and-butter" information for mechanical engineers who find themselves having to know about such components as electromagnets, solenoids and relays, special-purpose electric motors, synchros, various types of switches and timers, electromechanical clutches, brake speed reducers, timing devices, and mechanical applications of photo and load cells. In short, all the electromechanical help that an engineer may need in his work as a mechanical engineer and which, it seems, does not appear to be anywhere available in one complete source, will, it is hoped, be found in this book.

Douglas C. Greenwood