AGMA-ISO-1328-1-1999.pdf
STD-AGMA IS0 1328-L-ENGL E üb87575 00Uhi220 ThT ANSZ/AGMA ZSO 1328- 1 (IS0 1328- 1: 1995 IDT) AMERICAN NATIONAL STANDARD Cylindrical Gears - IS0 System of Accuracy - Part 1: Definitions and Allowable Values of Deviations Relevant to Corresponding Flanks of Gear Teeth AGMA STANDARD COPYRIGHT American Gear Manufacturers Association, Inc. Licensed by Information Handling Services COPYRIGHT American Gear Manufacturers Association, Inc. Licensed by Information Handling Services Am er i can Nat ion al Cylindrical Gears - IS0 System of Accuracy - Part 1: Definitions andAlIo wable Values of Deviations Relevant to Corresponding Flanks of Gear Teeth ANSI/AGMA IS0 1328-1 Approval of an American National Standard requires verification by ANSI that the require- ments for due process, consensus, and other criteria for approval have been met by the standards developer. Consensus is established when, in the judgment of the ANSI Board of Standards Review, substantial agreement has been reached by directly and materially affected interests. Substantial agreement means much more than a simple majority, but not necessarily una- nimity. Consensus requires that all views and objections be considered, and that a concerted effort be made toward their resolution. The use of American National Standards is completely voluntary: their existence does not in any respect preclude anyone, whether he has approved the standards or not, from manufacturing, marketing, purchasing, or using products, processes, or procedures not conforming to the standards. The American National Standards Institute does not develop standards and will in no circumstances give an interpretation of any American National Standard. Moreover, no person shall have the right or authority to issue an interpretation of an American National Standard in the name of the American National Standards Institute. Requests for interpre- tation of this standard should be addressed to the American Gear Manufacturers Association. CAUTION NOTICE: AGMA technical publications are subject to constant improvement, revision, or withdrawal as dictated by experience. Any person who refers to any AGMA technical publication should be sure that the publication is the latest available from the As- sociation on the subject matter. Fables or other self-supporting sections may be quoted or extracted. Credit lines should read: Extracted from ANSVAGMA IS0 1328-1 I Cylindrical Gears - IS0 System ofAccu- racy - Part 7: Definitions and Allowable Values of Deviations Relevant to Corresponding Flanks of Gear Teeth, with the permission of the publisher, the American Gear Manufacturers Association, 1500 King Street, Suite 201 Alexandria, Virginia 22314.1 Standard Approved November 17,1999 ABSTRACT This standard contains the IS0 system of accuracy relevant to corresponding flanks of individual cylindrical involute gears. It provides definitions for gear tooth accuracy terms, the structure of the gear accuracy system and the allowable values of pitch, profile and helix deviations. A normative annex for tangential composite toler- ances and an informative annex for allowable values of profile form, profile slope, helix form and helix slope deviations are provided. Published by American Gear Manufacturers Association 1500 King Street, Suite 201, Alexandria, Virginia 22314 Copyright O 1999 by American Gear Manufacturers Association All rights reserved. No part of this publication may be reproduced in any form, in an electronic retrieval system or otherwise, without prior written permission of the publisher. Printed in the United States of America ISBN: 1-55589-733-9 ii COPYRIGHT American Gear Manufacturers Association, Inc. Licensed by Information Handling Services COPYRIGHT American Gear Manufacturers Association, Inc. Licensed by Information Handling Services B U b B 7 5 7 'i 0 U 0 b 2 2 2 5 3 2 111 ANSI. AGMA .so 1328-1 AMERICAN NATIONAL STANDA F-. 3 Contents Page Foreword . iv 1 scope . 1 2 Normative reference . 1 3 Definitions . 1 4 Symbols and abbreviations . 6 5 Structure of the system of accuracy for gears . 7 6 Formulae for allowable values of gear deviations of accuracy grade 5 8 7 Allowable values of gear deviations relevant to corresponding flanks . 8 Tables 1 Single pitch deviation, *fPt 9 2 Total cumulative pitch deviation, Fp . 11 3 Total profile deviation, Fa 13 4 Total helix deviation. Fg . 15 Figures I Pitch deviations . 2 2 Profile deviations . 3 Tangential composite deviations . 6 Tolerances for tangential composite deviations . 17 Values of profile and helix form and slope deviations 21 3 Helixdeviationc . 5 4 Annexes A 6 Bibliography . . 29 . 111 COPYRIGHT American Gear Manufacturers Association, Inc. Licensed by Information Handling Services COPYRIGHT American Gear Manufacturers Association, Inc. Licensed by Information Handling Services EI nb87575 00üb223 479 iia ANSIIAGMA IS0 1328-1 AMERICAN NATIONAL STANDARD Foreword r h e foreword, footnotes and annexes, if any, in this document are provided for informational purposes only and are not to be construed as a part of ANWAGMA IS0 1328-1, Cylindrical Gears - IS0 System of Accuracy - Part 1: Definitions and Allowable Values of Deviations Relevant to Corresponding Flanks of Gear Teeth. This standard was developed by IS0 Technical Committee 60 as an International Standard with ANWAGMA participation. It was firsi published on 1995-02-15 then corrected and reprinted 1997-02-01. In general, the information in this standard covers similar subjects as covered in AN SI/AGMA 2000-A88, Gear Classification and Inspection Handbook - Tolerances and Measuring Methods for Unassembled Spur and Helical Gears, that currently exists. The user of this American National Standard is alerted that differences exist between it and ANWAGMA 2000-A88. Differences include, but are not limited to: Accuracy grade numbering system is reversed, such that the smallest number Tolerances are established by geometric mean values of relevant ranges of Relative magnitudes of elemental tolerances for a single grade are in a different The “profile evaluation range” and “helix evaluation range”, where the tolerances The “K Chart” is not used for the permissible tolerance values; Runout is not included as one of the elements with a tolerance; Concepts of “mean measurement trace”, “design profile”, “slope deviation” and Therefore, the user of ANWAGMA IS0 1328-1 must be very careful when comparing tolerance values formerly specified using AN WAGMA 2000-A88. ANWAGMA IS0 1328-1 is an identical adoption of IS0 1328-1:1995. Annex A forms an integral part of ANWAGMA IS0 1328-1. Annexes B and C are for information only. This version was approved by the AGMA membership in June 1999. It was approved as an American National Standard on November 17, 1999. Suggestions for improvement of this standard will be welcome. They should be sent to the American Gear Manufacturers Association, 1500 King Street, Suite 201, Alexandria, Virginia 2231 4. - represents the smallest tolerance; - parameters in tables, not by formulas: - proportion ; - are applied, are defined for less flank area than in ANSI/AGMA 2000-A88; - - - “form deviation” are defined. iv COPYRIGHT American Gear Manufacturers Association, Inc. Licensed by Information Handling Services COPYRIGHT American Gear Manufacturers Association, Inc. Licensed by Information Handling Services PERSONNEL of the AGMA inspection and Handbook Committee Chairman Classification Section: E. Lawson Mahr Corporation Chairman Measuring Methods Section: R.E. Smith R. E. Smith Company ACTIVE MEMBERS W.A. Bradley D.R. Choiniere . . J. Clatworthy B.L. Cox . T.C. Glasener . G.G. Grana . D. Heinrich . Consultant Fassler AG Lockheed Martin Energy Sys. Xtek, Incorporated The Gleason Works Xtek, Incorporated B. Hofrichter Arrow Gear Company S. Lindley The Falk Corporation D.A. McCarroll . . ZF Industries D.R. McVittie . . , , Gear Engineers, inc. L.J. Smith Invincible Gear Company Profile Engineering, Inc. I. Laskin Consultant . ASSOCIATE MEMBERS M. Antosiewicz . . The Falk Corporation M.J. Barron . Oliver Gear, Inc. R.E. Brown . Caterpillar, Inc. M.K. Considine . . Considine Associates R. Considine Considine Associates J.S. Cowan . Eaton Corporation M.E. Cowan M it does not cover gear pairs as such. It is strongly recommended that any user of this part of IS0 1328 be very familiar with the methods and procedures outlined in ISO/TR 10064-1. Use of techniques other than those of ISOFR 10064-1 combined with the limits described in this part of IS0 1328 may not be suitable. Annex A gives formulae for tolerances for tangential composite deviations which are also criterions of IS0 quality, but are not mandatory inspection items. Annex 6 provides values on profile and helix form and slope deviations which sometimes serve as useful information and evaluation values but are not mandatory inspection items. 2 Normative reference The following standard contains provisions which, through reference in this text, constitute provisions of this part of IS0 1328. At the time of publication, the edition indicated was valid. All standards are subject to revision, and parties to agreements based on this part of IS0 1328 are encouraged to investigate the possibility of applying the most recent edition of the standard indicated below. Members of IEC and IS0 maintain registers of currently valid International Standards. ISOTTR 10064- 1 : 1992, Cylindrical gears - Code of inspection practice - Pari 7: Inspection of corre- sponding flanks of gear teeth. 3 Definitions For the purposes of this part of IS0 1328, the following definitions apply. For the symbols not explained in this clause, see clause 4. 3.1 Pitch deviations 3.1 .I single pitch deviation (fpt): Algebraic difference between the actual pitch and the corresponding theoretical pitch in the transverse plane, defined on a circle concentric with the gear axis at approximately mid-depth of the tooth. (See figure 1 .) 3.1.2 cumulative pitch deviation (Fpk): Algebraic difference over any sector of k pitches, between the actual length and the theoretical length of the relevant arc. (See figure 1 .) In theory, it is equal to the algebraic sum of the single pitch deviations of the same k pitches. NOTE I Unless otherwise specified, evaluation of Fpk is limited to sectors not larger than one-eighth of the cir- cumference. Hence, allowablevalues of deviationsFpk apply to sectors of which the number of pitches (k) ranges from 2 to the number nearest to z/8. Generally, evaluation of Fpy8 is sufficient. If for special applica- tions (e.g., or high speed gears) smaller sectors are also to be checked, the relevant value(s) of k should be specified. 1 COPYRIGHT American Gear Manufacturers Association, Inc. Licensed by Information Handling Services COPYRIGHT American Gear Manufacturers Association, Inc. Licensed by Information Handling Services 3.1.3 total cumulative pitch deviation (F,): Maximum cumulative pitch deviation of any sector (with k = 1 up to k = z) of the corresponding flanks of a gear. It is represented by the total amplitude of the cumulative pitch deviation curve. 3.2 Profile deviations 3.2.1 profile deviation: Amount by which an actual profile deviates from the design profile. It is in the transverse plane and normal to the involute profile. 3.2.1 .I usable length (LAF): Difference between the lengths of two transverse base tangents, of which one extends from the base circle to the outer limit and the other extends from the base circle to the inner limit of the usable profile. Depending on the design, the usable length is limited by the tooth tip, by the start of tip chamfer or tip rounding (point A). Towards the root of the tooth, the usable length is limited either by the beginning of the root fillet or by the undercut (point F). 3.2.1.2 active length (LAE): That part of the usable length which is related to the active profile. Towards the tooth tip, it has the same limit as the usable length (point A). Toward the root of the tooth, the active length extends to the endpoint E of the effective contact with the mating gear (start of the active profile). If the mating gear is unknown, point E is the start of the active profile of engagement with a rack having standard basic rack tooth proportions. 3.2.1.3 profile evaluation range (La): That pari of the usable length to which the tolerances of the specified accuracy grade shall apply. Unless otherwise specified, its length is equal to 92% of the active length LE, extending from point E. (See figure 2.) NOTE 2 It is the responsibility of the gear designer to assure that the profile evaluation range is adequate for the application. For the remaining 8% of LAE, which is the zone near the tip expressed by the difference between LAE and La, the following evaluation rules apply for the total profile deviation and the profile form deviation: a) excess material (plus deviation) which in- crease the amount of deviation shall be taken into account ; b) unless otherwise specified, for minus devi- ations, the tolerance shall be three times the toler- ance specified for the evaluation range La. NOTE 3 For analysis ofthe profile form deviation, eval- uations a) and b) are based on the mean profile trace defined in 3.2.1.5. 3.2.1.4 design profile: A profile consistent with the design specification. When not otherwise qualified, it is the profile in a transverse plane. NOTE 4 In a profile diagram, the profile trace of an un- modified involute generally appears as a straight line. In figure 2, the design profile traces are shown as chain-dotted lines. - - - - -theoretical In this example Fpk = Fp3 actual Figure 1 - Pitch deviations 2 COPYRIGHT American Gear Manufacturers Association, Inc. Licensed by Information Handling Services COPYRIGHT American Gear Manufacturers Association, Inc. Licensed by Information Handling Services - - - : Design profile : Actual profile _ _ _ : Mean profile i) Design profile: unmodified involute i i) Design profile: modified involute (example) iii) Design profile: modified involute (example) Actual profile: Actual profile: with minus material deviations in the reduction zone with minus material deviations in the reduction zone Actual profile: with excess of material in the reduction zone TIP A ROOT TIP ROOT TIP ROOT E F A. E F A E F _ - - L AE ii) A E F 2 La- LAE iii) A E F A E I- , A E F o 4 L LAF A E F a) Total profile deviation b) Profile form deviation c) Profile slope deviation Figure 2 - Profile deviations 3.2.1.5 mean profile of a measured flank: Atrace determined by subtracting from the ordinates of the design profile trace the corresponding ordinates of a straight-line gradient. This is to be so done that, within the evaluation range, the sum of the squares of deviations of the actual profile trace from the mean profile trace is minimal. Thus, the position and the gradient of the mean profile trace is found by the “least-squares method”. NOTE 5 This profile
