The Engineering Resource For vancing Mobility 400 COMMONWEALTH DRIVE WARRENDALE, PA 15096 820459 An Easy Way to Know the Gear Ratio of Automatic Transmission by Using the Relative Speed Diagram Shinsei Maruyama The Institute of Vocational Training (Japan) International Congress & Exposition Detroit, Michigan February 22-26, 1982Downloaded from SAE International by University of New South Wales, Wednesday, September 19, 2018The appearance of the code at the bottom of the first page of this paper indicates SAE's consent that copies of the paper may be made for personal or internal use, or for the personal or internal use of specific clients. This consent is given on the con- dition, however, that the copier pay the stated per article copy fee through the Copyright Clearance Center, Inc., Operations Center, 21 Congress St., Salem, MA 01970 for copying beyond that permitted by Sections 107 or 108 of the U.S. Copyright Law. This consent does not extend to other kinds of copying such as copying for general distribution, for advertising or promotional purposes, for creating new collec- tive works, or for resale. Papers published prior to 1978 may also be copied at a per paper fee of $2.50 under the above stated conditions. SAE routinely stocks printed papers for a period of three years following date of publication. Direct your orders to SAE Order Department. To obtain quantity reprint rates, permission to reprint a technical paper or per- mission to use copyrighted SAE publications in other works, contact the SAE Publica- tions Division. ISSN 0148-7191 Copyright 1982 Society of Automotive Engineers, Inc.Downloaded from SAE International by University of New South Wales, Wednesday, September 19, 2018820459 An Easy Way to Know the Gear Ratio of Automatic Transmission by Using the Relative Speed Diagram Shinsei Maruyama The Institute of Vocational Training (Japan) WHEN OVERHAULING AND ADJUSTING AN AUTO- MOBILE, first of all, it is necessary to understand its mechanism and function; for example, it is difficult to adjust an auto- matic transmission without the knowledge of its mechanism and function. The basic point of such knowledge is to know the gear ratio of the transmission. To know the gear ratio of the transmission having planetary gears, so-called a method of fixed mechanism (a gluing method) has been used. However, with this method, it was usually not easy to know the gear ratio of the complicated automatic transmission. The author developed an easy way to calculated the gear ratio by using a simple relative speed diagram. With this method, as even a graduate of junior high school can calculate the gear ratio of relatively com- plicated automatic transmission, the methodis widely used at vocational centers, vocational schools and junior colleges of vocational training dotted all over Japan effectively. RELATIVE SPEED Relative speed of a linear motion In Fig.l, car A is cruising at a speed of VA 70 km/h, while the speed of car B is ' VB=100 km/h. When car B passes car A, a person in car B feels as if car A is going back i.e., it seems to.him that car A is moving at a speed of VA-VB while car B is stopped. The speed difference VA-VB is called the relative speed of car A against car B (with car B as a basis) and is written using a notation V as follows:AB ABSTRACT It is usually not easy to know the gear ratio of automatic transmission with planetary gears. The author developed an easy way to calculate the gear ratio by using a simple relative speed diagram. With this method, as even a graduate of junior high school cancalculate the gear ratio of relatively complicated automatic transmission, the method is widely used at vocational centers, vocational schools and junior colleges of vocational training dotted all over Japan effectively. 0148-7191/8210222-0459802.50 Copyright 1982 Society of Automotive Engineers, Inc,Downloaded from SAE International by University of New South Wales, Wednesday, September 19, 2018A B C (a)