1、 SAE Technical Standards Board Rules provide that: “This report is published by SAE to advance the state of technical and engineering sciences. The use of this report is entirely voluntary, and its applicability and suitability for any particular use, including any patent infringement arising there
2、from, is the sole responsibility of the user.” SAE reviews each technical report at least every five years at which time it may be reaffirmed, revised, or cancelled. SAE invites your written comments and suggestions. Copyright 2010 SAE International All rights reserved. No part of this publication m
3、ay be reproduced, stored in a retrieval system or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of SAE. TO PLACE A DOCUMENT ORDER: Tel: 877-606-7323 (inside USA and Canada) Tel: 724-776-4970 (outside USA)
4、 Fax: 724-776-0790 Email: CustomerServicesae.org SAE WEB ADDRESS: http:/www.sae.org SAE values your input. To provide feedback on this Technical Report, please visit http:/www.sae.org/technical/standards/j649_201001J649 JAN2010 SURFACE VEHICLE RECOMMENDED PRACTICE Issued 1957-01 Revised 2010-01 Supe
5、rseding J649 MAY2000 Automatic Transmission FunctionsTerminology RATIONALE This document has been revised for improved clarification and terminology updates to current nomenclature. 1. SCOPE The following is a list of the most common terminology used in describing automatic transmission functions. 2
6、 REFERENCES There are no referenced publications specified herein. 3. DEFINITIONS 3.1 Friction Launch The use of a friction driving member in launching a vehicle from a standing position. 3.2 Fluid Launch The use of a hydrodynamic or hydrostatic drive unit in launching a vehicle from a standing pos
7、ition. 3.3 Converter Clutch Engagement The transition from hydrodynamic to mechanical drive normally accomplished through the application of a friction element. 3.4 Shift A control system actuated change in the functioning of the torque transmitting drive (this could be a gear train, a hydrodynamic
8、or hydrostatic drive unit, electrical or friction drive mechanism, and so forth) which results in a change in torque ratio and speed ratio. 3.5 Upshift A shift which results in a decrease in torque ratio and an increase in speed ratio. SAE J649 Revised JAN2010 Page 2 of 3 3.6 Downshift A shift which
9、 results in an increase in torque ratio and a decrease in speed ratio. 3.7 Power Shift A shift which occurs without interruption of drive. 3.8 Torque Break or Torque Interrupt Shift A shift which occurs while the drive is interrupted. 3.9 Overlap Shift A shift during which the torque transmitting el
10、ements of more than one driving ratio are engaged simultaneously for a short interval. 3.10 Underlap Shift A shift during which the releasing clutch slips due to the torque transmitted being higher than the clutch torque capacity for a short interval before the applying element can hold the transmit
11、ted torque. 3.11 Freewheel or Non-Synchronous Shift A torque shift in which a one-way clutch is involved as an element of one of the drive ratios from which or to which a shift is made. 3.12 Manual Shift A shift which results from the action of the manually operated part of the control system. 3.13
12、Automatic Shift A shift which results from the action of the automatically operating part of the control system. 3.14 Inhibited Shift A shift which is automatically prevented under certain predetermined conditions of operation. 3.15 Backout Shift An upshift which occurs with a reduction in throttle
13、opening with vehicle in motion. 3.16 Coastdown Shift A downshift which occurs with closed throttle and vehicle decelerating. 3.17 Part Throttle Shift A shift which is obtained at a throttle position short of full throttle. 3.18 Wide Open Throttle Shift A shift which is obtained at maximum throttle p
14、osition. SAE J649 Revised JAN2010 Page 3 of 3 4. NOTES 4.1 Marginal Indicia A change bar (I) located in the left margin is for the convenience of the user in locating areas where technical revisions, not editorial changes, have been made to the previous issue of this document. An (R) symbol to the l
15、eft of the document title indicates a complete revision of the document, including technical revisions. Change bars and (R) are not used in original publications, nor in documents that contain editorial changes only. PREPARED BY THE SAE AUTOMATIC TRANSMISSION & TRANSAXLE TECHNICAL STANDARDS COMMITTEE
