The JIS B 1702-1 standard, titled "Cylindrical gears—ISO system of flank tolerance classification—Part 1: Definitions and allowable values of deviations relevant to flanks of gear teeth," provides a comprehensive framework for the accuracy and quality of individual cylindrical involute gears. It was revised in 2016 to align with international ISO standards. Key Features and Scope
Tolerance Classification System: It establishes a system for classifying the accuracy of gear tooth flanks, moving away from older numerical grading systems (like the previous JIS B 1702:1976) toward the ISO-aligned system.
Definitions of Deviations: The standard provides formal definitions and calculation methods for several types of gear errors:
Pitch Deviations: Including single pitch, cumulative pitch, and total pitch deviations.
Profile Deviations: Measuring how much the actual tooth profile differs from a theoretical involute curve.
Helix (Lead) Deviations: Measuring the deviation of the tooth trace from its intended axial path.
Allowable Values: It specifies the maximum permissible deviation values (tolerances) for different accuracy classes. Common classes found in industrial catalogs include Class 5 (high precision ground gears) and Class 9 (general use).
Annexes for Evaluation: The standard includes informative annexes for advanced analysis, such as: Zone-based tolerance evaluation (Annex A).
Second-order analysis method for profile and helix deviations (Annex B). Allowable runout values (Annex E). Reference Documents
You can find further technical details and specific tables in the following resources:
Official Preview: A technical preview of the JIS B 1702-1:2016 is available via the Japanese Standards Association (JSA).
Detailed Accuracy Guides: Manufacturers like KHK Gears and QTC Metric Gears provide technical catalogs that explain how these JIS standards apply to specific gear products.
Technical Explanations: A summary of Gear Accuracy Standards per JIS B 1702 can be found on Scribd.
JIS B 1702-1:2016 Cylindrical gears -- ISO system of flank tolerance
The JIS B 1702-1:2016 standard, titled "Cylindrical gears—ISO system of flank tolerance classification—Part 1: Definitions and allowable values of deviations relevant to flanks of gear teeth," is a Japanese Industrial Standard that aligns with ISO systems to classify gear accuracy. You can find a preview of the official document at the Japanese Standards Association (JSA) or purchase the full PDF from retailers like Intertek Inform and the ANSI Webstore.
Below is a draft of a technical summary/white paper based on the specifications of this standard.
Technical Paper: Application of JIS B 1702-1 in Gear Accuracy Classification 1. Introduction
The JIS B 1702-1:2016 standard provides a rigorous framework for the tolerance classification of tooth flanks in individual cylindrical involute gears. By establishing standardized definitions and allowable deviation values, it ensures interchangeability and performance reliability in mechanical systems. 2. Scope and Definitions
This part of the JIS B 1702 series specifically addresses deviations relevant to the flanks of gear teeth. It defines critical parameters for measuring accuracy, including:
Pitch Deviations: Including single pitch error, pitch variation, and accumulated pitch error.
Profile Deviations: The deviation of the actual tooth profile from the ideal involute curve.
Helix (Lead) Deviations: Accuracy along the width of the gear tooth. 3. The Tolerance Classification System
The standard utilizes a grade-based system (typically ranging from Grade 0 to Grade 12) to categorize gear precision.
High-Precision Grades: Used in high-speed or high-load applications where noise and vibration must be minimized.
Commercial Grades: Suitable for general machinery where moderate tolerances are acceptable. 4. Methodologies for Evaluation
Accuracy is determined through specific measurement techniques outlined in the standard's informative annexes:
Annex B: Evaluation of profile and helix deviations using second-order analysis. Annex C: Filtering methods for profile and helix data. Annex E: Runout evaluation guidelines. 5. Conclusion
Adherence to JIS B 1702-1:2016 allows manufacturers to communicate precision levels clearly using a globally recognized ISO-aligned language. This standardization is essential for the design of high-performance spur and helical gears in modern engineering. JIS B 1702-1:2016 - Cylindrical gears - ANSI Webstore
Finding a direct, legal free PDF download of JIS B 1702-1 ("Involute gears -- Part 1: Rating of surface stress and bending stress") is generally not possible because it is a copyrighted standard sold by the Japanese Standards Association (JSA).
However, there are several highly useful resources and papers that explain, apply, and compare this standard, which are often more helpful for engineers than the raw standard document itself.
Here is a guide to useful resources regarding JIS B 1702-1: jis b 1702-1 pdf
JIS B 1702-1 is more than just a chart of numbers; it is the backbone of gear quality control in Japan. For engineers sourcing components from Japanese suppliers or manufacturing for the Japanese market, understanding the specific deviation allowances in this standard is mandatory to ensure mechanical reliability and minimize transmission noise.
JIS B 1702-1 standard, titled "Cylindrical gears — ISO system of flank tolerance classification — Part 1: Definitions and allowable values of deviations relevant to corresponding flanks of gear teeth,"
is the Japanese Industrial Standard for gear precision, based directly on ISO 1328-1 Overview of JIS B 1702-1
This standard establishes a classification system for the accuracy of cylindrical involute gears. It replaced the older 1976 version of JIS B 1702, shifting from a "grade" system (0–9) to a "tolerance class" system (equivalent to ISO 0–12) to align Japanese manufacturing with international benchmarks. Key Technical Aspects Accuracy Classes : It defines 13 tolerance classes, where represents the highest precision (master gears) and represents the lowest. Measurement Parameters
: The standard focuses on individual tooth deviations, including: Profile Deviation ( cap F sub alpha
The difference between the actual and theoretical tooth profile. Helix Deviation ( cap F sub beta
The accuracy of the tooth along its width (axial direction). Pitch Deviation ( cap F sub p
The spacing accuracy between adjacent teeth and the cumulative spacing over the entire gear.
: It applies to gears with pitch diameters up to 10,000 mm and modules ranging from 0.5 to 70. Practical Application
Engineers use JIS B 1702-1 to specify the required precision for gears based on their end-use. For example: High-speed turbines typically require Class 4 or 5. General industrial machinery often utilizes Class 8 or 9. Automotive transmissions
usually demand Class 6 or 7 for noise reduction and durability. Accessing the PDF Because JIS standards are copyrighted by the Japanese Standards Association (JSA)
, official PDF copies are generally not available for free. You can obtain the document through: JSA Web Store
: The primary source for the official Japanese and English translated versions. ANSI Webstore / IHS Markit
: International resellers that provide digital access to industrial standards. comparison table
between the old JIS grades and the current ISO-aligned classes?
JIS B 1702-1 is the Japanese Industrial Standard for cylindrical gear flank tolerance, adopting ISO 1328-1 to define accuracy grades (0-12) for gear quality control. The standard provides detailed mathematical formulas and tolerance tables for designing and inspecting precision machinery components, ensuring compatibility with international benchmarks. For purchasing the official PDF, visit the Japanese Standards Association (JSA) website.
JIS B 1702-1 standard, officially titled "Cylindrical gears — ISO system of flank tolerance classification — Part 1: Definitions and allowable values of deviations relevant to flanks of gear teeth,"
is the primary Japanese industrial standard for defining the accuracy and tolerances of individual cylindrical involute gears. 日本規格協会 JSA GROUP Webdesk Standard Overview Current Version : JIS B 1702-1:2016.
: Specifies the tolerance classification system for tooth flanks of individual cylindrical involute gears, including definitions for gear flank tolerance terms and allowable values. Key Parameters Defined Pitch Deviations : Single pitch deviation ( f sub p t end-sub ) and total cumulative pitch deviation. Profile Deviations
: Total profile deviation, profile form deviation, and profile slope deviation. Helix (Lead) Deviations
: Total helix deviation, helix form deviation, and helix slope deviation. Accuracy Grades : Defines 13 grades of gear accuracy (0 through 12), where is the highest accuracy and is the lowest. Intertek Inform Where to Access the PDF
You can obtain official or preview copies of the standard through the following sources: Japanese Standards Association (JSA)
: The official publisher. A preview of the 2016 edition is available on the JSA Webdesk ANSI Webstore ANSI Webstore provides the full document for purchase and subscription. Intertek Inform : This platform offers the current JIS B 1702-1:2016 and historical versions like the 1998 edition.
: User-uploaded versions (often for viewing or with a subscription) can be found for the 2016 version gear accuracy summaries Technical Application For practical engineering application, manufacturers like
provide extensive technical references that translate these JIS standards into usable tables for gear design and selection. differences
between the current 2016 version and the older 1998 or 1976 standards? Jis B 1702-1 | PDF - Scribd
Understanding JIS B 1702-1: A Guide to Gear Accuracy Standards (PDF & Basics)
When designing or sourcing gears, understanding accuracy standards is crucial for performance, noise reduction, and longevity. The JIS B 1702-1
standard is the go-to reference for gear engineers, particularly in Asian manufacturing.
This post breaks down what JIS B 1702-1 covers, the difference between old and new standards, and where to find the technical specifications. What is JIS B 1702-1? JIS B 1702-1 The JIS B 1702-1 standard, titled "Cylindrical gears—ISO
(Cylindrical gears—ISO system of flank tolerance classification) is a Japanese Industrial Standard that defines the accuracy grades for the tooth flanks of individual cylindrical involute gears. It sets the allowable deviations (tolerances) for: Pitch Errors: Single pitch, cumulative pitch. Tooth Profile Error: How closely the gear teeth match the ideal involute curve. Helix Error (Lead Error): The accuracy of the tooth alignment across the face width. Key Takeaways: JIS B 1702-1:2016 vs. 1998
The standard has evolved to align with international ISO standards. JIS B 1702-1:2016 (Current):
Replaces the 1998 version, focusing on flank tolerance classification. JIS B 1702-1:1998 (Historical):
Often referred to in older designs, covering 13 grades of accuracy (0–12). "N" Grade:
If you see "N" before a grade (e.g., N7), it indicates it follows the newer JIS B 1702 standards rather than the obsolete 1976 standard. Gear Accuracy Grades (N0–N12)
JIS B 1702-1 defines 13 grades (grouped from 0, the highest precision, to 12, the lowest). Application Grade Type of Gear
High-precision, high-speed (Robotics, Aircraft, Machine tools)
General precision (Automotive transmissions, High-load industrial) General purpose (General industrial machinery) N9 – N12 Lower precision (Conveyors, Slow agricultural machinery) Where to Access the JIS B 1702-1 PDF
As a technical standard, the full text of JIS B 1702-1 is protected by copyright. You can purchase the official documentation from the following sources: JSA (Japanese Standards Association) Webdesk The primary source for English editions. TechStandardsStore Authorized provider of JIS PDFs. Standards Supply Another reputable source for purchasing the document. Key Technical Aspects for Designers Module Range:
The standards are typically applied to gears with a normal module (
) from 0.1mm to 2.0mm in some specialized standards, or much larger in general industrial applications. Measuring Techniques: It is recommended to use the procedures outlined in ISO/TR 10064-1 to evaluate the deviations defined in JIS B 1702-1. Pairing with JIS B 1702-2: While Part 1 focuses on individual tooth flank accuracy, JIS B 1702-2
covers radial composite deviations (how the gear performs when meshed).
Disclaimer: Standards documents are updated periodically. Always check the Japanese Standards Association website for the most recent revision. Accuracy of Gears | KHK
JIS B 1702-1 is the Japanese Industrial Standard for the ISO system of flank tolerance classification for cylindrical gears. It provides the technical definitions and allowable values for gear tooth deviations, serving as the primary benchmark for gear precision in Japanese engineering. Core Purpose and Scope
This standard establishes a system to classify the accuracy of individual cylindrical involute gears. It focuses on "flank tolerance," which refers to the physical accuracy of the tooth's surface.
Part 1 Focus: Definitions and allowable values for deviations relevant to the flanks of gear teeth.
Applicability: It applies to both spur and helical gears with parallel axes.
Current Version: The most recent revision is JIS B 1702-1:2016, which replaced the 1998 version to align more closely with International ISO standards. Key Technical Elements
The document defines several types of tooth deviations that impact gear performance:
Pitch Deviations: Errors in the spacing between teeth, affecting the smoothness of rotation.
Profile Deviations: Variations from the theoretical involute curve, which can cause noise and vibration.
Helix Deviations: Errors in the orientation of the tooth along the gear's axis (lead errors).
Runout: The variation in the radial position of the teeth relative to the gear's center. Practical Implementation
In industrial catalogs (like those from Misumi or KHK), you will often see gear precision rated by "Class". Jis B 1702-1 | PDF - Scribd
The JIS B 1702-1 standard, titled "Cylindrical gears — ISO system of flank tolerance classification — Part 1: Definitions and allowable values of deviations relevant to flanks of gear teeth," is the definitive Japanese technical guideline for gear accuracy. The current version, JIS B 1702-1:2016, aligns Japanese industrial practices with international ISO standards to ensure global interchangeability. 1. Scope and Application
This standard establishes a system for classifying the accuracy of individual cylindrical involute gears.
Target Components: Specifically covers spur and helical gears.
Metric System: It is fundamentally a metric standard, often used alongside ISO 1328-1.
Precision Grades: The standard defines 13 grades of gear accuracy, ranging from Grade 0 (highest precision) to Grade 12 (lowest precision). 2. Primary Measurement Definitions
JIS B 1702-1 focuses on "flank deviations," which are errors in the physical shape and positioning of the gear teeth: Deviation Type Description Single Pitch Deviation fptf sub p t end-sub or legal liability in commercial use.
The difference between the actual measured pitch and the theoretical circular pitch between adjacent teeth. Total Cumulative Pitch Deviation Fpcap F sub p
The maximum difference between the actual and theoretical distance over any number of teeth. Total Profile Deviation Fαcap F sub alpha
Measures how much the actual tooth profile deviates from the ideal involute curve. Total Helix Deviation Fβcap F sub beta
Errors in the axial direction (lead error), which can cause poor tooth contact and noise. 3. Key Updates (Old vs. New Standards)
Modern gear design often distinguishes between the "Old JIS" (B 1702:1976) and the "New JIS" (B 1702:1998/2016).
Grade Prefixes: New standard grades are often prefixed with an "N" (e.g., Grade N5) to distinguish them from the old 0-8 scale.
ISO Alignment: The 1998 revision and the current 2016 version were specifically designed to match ISO system of flank tolerance to facilitate international trade. 4. Technical Resources and Compliance
Page 1. JIS. JAPANESE. INDUSTRIAL. STANDARD. Translated and Published by. Japanese Standards Association. JIS B 1702-1. (JGMA/JSA) 日本規格協会 JSA GROUP Webdesk
JIS B 1702-1:2016 Cylindrical gears -- ISO system of flank tolerance
The JIS B 1702-1 is a Japanese Industrial Standard that defines the accuracy and tolerance classification for cylindrical gears (spur and helical gears). It was last revised in 2016 and is technically aligned with the international standard ISO 1328-1. 🔩 Core Purpose
This standard provides the framework for classifying the quality of a gear based on its deviations. It is essential for engineers and manufacturers to ensure that gears fit correctly and perform predictably in machinery. 📋 Key Components
The standard focuses on four primary types of gear deviations:
Pitch Deviations: Differences in the distance between corresponding points on adjacent teeth.
Profile Deviations: Deviations of the actual tooth profile from the theoretical involute shape.
Helix Deviations: Variations in the tooth surface along the axial direction (lead error).
Tangential Composite Deviations: Combined errors measured as the gear rotates. 📊 Understanding Accuracy Grades
Grade System: Gears are assigned a numeric grade (typically 0 to 12).
Higher Precision: Lower numbers (e.g., Grade 0 or 1) indicate extremely high precision, used in aerospace or master gears.
Standard Industrial: Grades 6 through 9 are common for general industrial machinery.
Rough Work: Higher numbers indicate looser tolerances for less critical applications. 🔗 Where to Access the PDF
The full document is protected by copyright and typically requires a purchase or a subscription.
Official Source: You can buy the official English or Japanese version through the Japanese Standards Association (JSA) Webdesk.
Previews & Guides: Technical summaries and calculation guides are often available via manufacturers like KHK Gears or Scribd for educational purposes.
📍 Key Anchor: This standard is part of a 3-part series; Part 2 covers radial composite deviations, and Part 3 specifically addresses injection-molded plastic gears.
The JIS B 1702-1 PDF is copyrighted material. Free distribution via public websites is illegal. However, there are legitimate ways to obtain it:
| Source | Method | Cost | Notes | |--------|--------|------|-------| | JSA Web Store (Japanese Standards Association) | Direct purchase and download | ~¥4,200 + tax | Official PDF with digital watermarking. | | KIKAKU (JISC’s official portal) | Free web viewing, but no PDF download | Free | Allows read-only access; printing disabled. | | ISO Store (for identical ISO 1328-1:2013) | Purchase PDF | ~¥12,000 | More expensive than JIS version. | | National Standard Bodies (e.g., ANSI in USA, BSI in UK) | Resell as adopted standard | Varies | Often bundled with commentary. |
Important: Websites claiming to offer a “free PDF download” of JIS B 1702-1 (e.g., docplayer, pdfcoffee, chomikuj) are almost always uploading copyrighted material without authorization. Downloading from such sites may expose you to malware, outdated drafts, or legal liability in commercial use.
Here is the hard truth for those looking for a zero-cost download: Most free PDFs of JIS B 1702-1 are either illegal copies, outdated drafts, or watermarked previews.
The Japanese Standards Association strictly enforces copyright. Unlike open-source software manuals, industrial standards are revenue streams for national bodies.