Agma Ansi Iso1328 1 99
Agma Ansi Iso1328 1 99
Agma Ansi Iso1328 1 99
American
National
Standard
ABSTRACT
This standard contains the ISO 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 tolerances and an informative annex for allowable values of profile form, profile slope, helix form and helix slope
deviations are provided.
Published by
ii
Contents
Page
Foreword . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1
Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2
Normative reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3
Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4
Symbols and abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5
Structure of the system of accuracy for gears . . . . . . . . . . . . . . . . . . . . . . . . . . .
6
Formulae for allowable values of gear deviations of accuracy grade 5 . . . . . .
7
Allowable values of gear deviations relevant to corresponding flanks . . . . . . .
iv
1
1
1
6
7
8
8
Tables
1
2
3
4
Figures
1
2
3
4
Pitch deviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Profile deviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Helix deviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Tangential composite deviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2
3
5
6
Annexes
A
B
Bibliography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
iii
Foreword
[The 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 ANSI/AGMA ISO
1328--1, Cylindrical Gears -- ISO System of Accuracy -- Part 1: Definitions and Allowable
Values of Deviations Relevant to Corresponding Flanks of Gear Teeth.]
This standard was developed by ISO Technical Committee 60 as an International Standard
with ANSI/AGMA participation. It was first 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 ANSI/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
ANSI/AGMA 2000--A88. Differences include, but are not limited to:
-- Accuracy grade numbering system is reversed, such that the smallest number
represents the smallest tolerance;
-- Tolerances are established by geometric mean values of relevant ranges of
parameters in tables, not by formulas;
-- Relative magnitudes of elemental tolerances for a single grade are in a different
proportion;
-- The profile evaluation range and helix evaluation range, where the tolerances
are applied, are defined for less flank area than in ANSI/AGMA 2000--A88;
--
--
iv
ACTIVE MEMBERS
W.A. Bradley . . . .
D.R. Choiniere . .
J. Clatworthy . . . .
B.L. Cox . . . . . . .
T.C. Glasener . . .
G.G. Grana . . . . .
D. Heinrich . . . . .
Consultant
Profile Engineering, Inc.
Fassler AG
Lockheed Martin Energy Sys.
Xtek, Incorporated
The Gleason Works
Xtek, Incorporated
B. Hofrichter . . . .
I. Laskin . . . . . . . .
S. Lindley . . . . . .
D.A. McCarroll . .
D.R. McVittie . . . .
L.J. Smith . . . . . .
G.A. Luetkemeier
J. Marfice . . . . . .
D. Matzo . . . . . . .
M. May . . . . . . . . .
P.A. McNamara .
W.J. Michaels . . .
M. Milam . . . . . . .
T. Miller . . . . . . . .
M. Nanlawala . . .
M. Octrue . . . . . .
T. Okamoto . . . . .
J.A. Pennell . . . . .
K.R. Price . . . . . .
R.S. Ramberg . . .
V.Z. Rychlinski . .
D.H. Senkfor . . . .
S. Shariff . . . . . . .
E.L. Storm . . . . . .
T. Waldie . . . . . . .
R.F. Wasilewski .
F.M. Young . . . . .
P. Zwart . . . . . . .
Rockwell Automation/Dodge
Caterpillar, Inc.
Northwest Gears, Inc.
The Gleason Works
Caterpillar, Inc.
Sundstrand Corporation
Amarillo Gear Company
The Cincinnati Gear Co.
IIT Research Institute
CETIM
Nippon Gear Company, Ltd.
Univ. of Newcastle--Upon--Tyne
Eastman Kodak Company
The Gear Works -- Seattle, Inc.
Brad Foote Gear Works, Inc.
Precision Gear Company
PMI Food Equipment Group
Consultant
Philadelphia Gear Corporation
Arrow Gear Company
Frorest City Gear Company
Caterpillar, Inc.
ASSOCIATE MEMBERS
M. Antosiewicz . .
M.J. Barron . . . . .
R.E. Brown . . . . .
M.K. Considine . .
R. Considine . . . .
J.S. Cowan . . . . .
M.E. Cowan . . . .
B. Cowley . . . . . .
C. Dick . . . . . . . . .
H.D. Dodds . . . . .
R. Green . . . . . . .
D. Gregory . . . . .
B. Gudates . . . . .
J.S. Hamilton . . .
H. Harary . . . . . . .
G. Henriot . . . . . .
J. Horwell . . . . . .
S. Johnson . . . . .
T. Klemm . . . . . . .
D.E. Kosal . . . . . .
J. Koshiol . . . . . .
W.E. Lake . . . . . .
A.J. Lemanski . . .
vi
2 Normative reference
3 Definitions
1 Scope
This part of ISO 1328 establishes a system of
accuracy relevant to corresponding flanks of individual cylindrical involute gears.
It specifies appropriate definitions for gear tooth
accuracy terms, the structure of the gear accuracy
system and the allowable values of pitch deviations,
total profile deviations and total helix deviations.
+fpt
pt
k pt
+Fpk
theoretical
actual
In this example Fpk = Fp3
Figure 1 -- Pitch deviations
2
Key
i)
Design profile:
Actual profile:
unmodified involute
with minus material deviations in the reduction zone
ii)
Design profile:
Actual profile:
iii)
Design profile:
Actual profile:
ROOT
E F
fH
LAE
LAF
ff
-L
LAE
LAF
LAF
ff
fH
L--
L--
-L
LAE
LAF
LAE
LAF
LAE
LAF
E F
L
LAE
LAF
E F
+
--
-L
LAE
+
F
E F
+
iii)
LAE
LAF
fH
LAE
LAF
E F
-L
-L
ii)
ROOT
E F
TIP
A
+
ff
--
ROOT
E F
TIP
A
+
TIP
A
i)
: Mean profile
: Actual profile
: Design profile
E F
3.4.2 tooth--to--tooth tangential composite deviation (fi): Value of the tangential composite
deviation over a displacement of one pitch. (See
figure 4.)
Key
i)
Design helix:
Actual helix:
unmodified helix
with minus material deviations in the reduction zone
ii)
Design helix:
Actual helix:
iii)
Design helix:
Actual helix:
II
fH
-L
II
II
+
II
fH
--
ff
--
--
II
+
--
--
L
b
II
+
ff
-L
iii)
II
-L
i)
ii)
II
+
ff
II
+
fH
: Mean helix
: Actual helix
: Design helix
-L
Accuracy grade
Reference face
II
Non--reference face
Facewidth
Reference diameter
Module
pt
Transverse pitch
Number of teeth
F
LAE
ff
ff
fH
1)
fH1)
f i
fpt1)
Fi
Fp
LAF
Fpk
Fi
f i
25
23
21
19
17
15
13
11
Tooth No. 1
Figure 4 -- Tangential composite deviations
_____________
These deviations can be plus or minus.
1)
1 25
10
11
12
13
14
15
16
Annex A
(normative)
Tolerances for tangential composite deviations
A.1 General
Unless otherwise specified in procurement documents, the measurement of tangential composite
deviations is not mandatory. Tolerances for these
deviations are therefore not included in the main
body of this part of ISO 1328.
However, when agreed between the supplier and
purchaser, the method, preferably accompanied by
a check of tooth contact, can sometimes be applied
to replace some of the other inspection processes.
Definitions of the tooth--to--tooth tangential composite deviation and of the total tangential composite
deviation are given in 3.4.
Tolerance values for tooth--to--tooth tangential composite deviations f i are calculated either by multiplying the numerical values f i /K given in table A.1 by
the factor K (K is as defined in A.2.1) or with the
formulae given in A.2.1 for accuracy grade 5 and, for
any other accuracy grade, by applying the same
calculation rules as those stated in clause 5. For
rounding the deviation values, the rules stated in
clause 5 shall apply for (f i /K) K.
Tolerance values for total tangential composite
deviations Fi for accuracy grade 5 are calculated
with the formula given in A.2.2. Rules for calculating
the values of different accuracy grades and for
rounding of deviation values are the same as those
stated in clause 5.
When checking the tangential composite deviation
accuracy grade, the gear to be inspected shall mesh
with a master gear at an appropriate centre distance
(i.e., with a certain backlash) whilst contact is
restricted to only one set of corresponding flanks, by
applying a light but sufficient load.
f i = K 4.3 + f pt + F =
i.e.,
K = 0.2
+ 4
for < 4
K = 0.4 for 4
If the facewidths of the product gear and master gear
are different, the calculation of is to be carried out
using the smaller facewidth.
If the profile and/or the helix of the teeth are
extensively modified, the effective values of and K
under test conditions can be so strongly affected that
these must be taken into account when assessing
the results of measurement. In these cases, special
agreements on test conditions and evaluation on
recorded diagrams are advisable.
A.2.2 Total tangential composite deviation, Fi, is
calculated as follows:
F i = F p + f i
17
18
19
20
Annex B
(informative)
Values of profile and helix form and slope deviations
[The foreword, footnotes and annexes, if any, are provided for informational purposes only and should not be
construed as a part of ANSI/AGMA ISO 1328--1, Cylindrical Gears -- ISO System of Accuracy -- Part 1: Definitions
and Allowable Values of Deviations Relevant to Corresponding Flanks of Gear Teeth.]
B.1 General
Since the form and slope deviations of profiles and
helices are not individually subject to mandatory
tolerances, none are provided as normative elements in this part of ISO 1328. However, as form and
slope deviations have a substantial influence on the
performance characteristics of the gear, relevant
values are given in tables B.1 to B.3. Definitions of
profile and helix form and slope deviations are given
in 3.2.3 and 3.2.4 and in 3.3.3 and 3.3.4.
B.2 Formulae for values of accuracy grade 5
B.2.1 Profile form deviation ff=, is calculated from
f f= = 2.5 m + 0.17 d + 0.5
21
22
23
24
25
Table B.3 -- Helix form deviation, ff, and helix slope deviation, fH
26
27
Bibliography
The following documents are either referenced in the text of ANSI/AGMA ISO 1328--1, Cylindrical Gears -- ISO
System of Accuracy -- Part 1: Definitions and Allowable Values of Deviations Relevant to Corresponding Flanks
of Gear Teeth or indicated for additional information.
1)
ISO 53: 1974, Cylindrical gears for general and heavy engineering -- Basic rack.
2)
ISO 54:1977, Cylindrical gears for general engineering and for heavy engineering -- Modules and
diametral pitches.
3)
4)
5)
ISO/TR 10064--2:1996, Cylindrical gears -- Code of inspection practice -- Part 2: Inspection related to
radial composite deviations, runout, tooth thickness and backlash.
28
PUBLISHED BY
AMERICAN GEAR MANUFACTURERS ASSOCIATION
1500 KING STREET, ALEXANDRIA, VIRGINIA 22314