Understanding JIS B 1702-1: The Standard for Gear Accuracy The JIS B 1702-1 standard is the primary Japanese Industrial Standard for classifying the accuracy of cylindrical involute gears. Established by the Japanese Standards Association (JSA), it provides the technical definitions and allowable deviation values for tooth flanks, ensuring precision in mechanical systems ranging from heavy industrial machinery to high-precision robotics. Overview of JIS B 1702-1:2016
The current version of this standard is JIS B 1702-1:2016, which officially replaced the older 1998 and 1976 editions. It is largely harmonized with the international standard ISO 1328-1:1995, allowing Japanese manufacturers to maintain global compatibility. Scope and Application
This part of the JIS B 1702 series specifically covers the "ISO system of flank tolerance classification". It applies to individual cylindrical gears rather than gear pairs. The standard defines:
Accuracy Grades: It describes 13 grades of gear accuracy, ranging from Grade 0 (the highest precision) to Grade 12 (the lowest).
Measurement Parameters: Accuracy is determined by evaluating specific deviations, including: Single Pitch Deviation ( fptf sub p t end-sub
): The difference between the actual measured pitch and the theoretical circular pitch.
Total Profile Deviation: Measures how closely the actual tooth profile matches the ideal involute curve.
Total Helix Deviation: Evaluation of the tooth trace or lead error. Technical Constraints
The tolerances outlined in JIS B 1702-1 apply to gears within specific geometric ranges: Reference Diameter ( ): 5 mm to 15,000 mm. Normal Module ( ): 0.5 mm to 70 mm. Number of Teeth ( ): 5 to 1,000. Helix Angle ( ): Up to 45°. Comparison with Related Standards jis b 1702-1 pdf
The JIS B 1702 series is divided into multiple parts to address different measurement methods and materials: Accuracy of Gears | KHK
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) Understanding JIS B 1702-1: The Standard for Gear
: 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
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:
While technical summaries provide an overview, the actual JIS B 1702-1 PDF document is required for manufacturing and compliance. The standard contains complex look-up tables for tolerance values based on the module, reference diameter, and tooth width. It is largely harmonized with the international standard
Where to find the official PDF:
If you are designing gears for an international market, understanding how JIS B 1702-1 differs from other standards is critical.
The standard contains dozens of numeric tables (e.g., Table 1 through Table 12) that provide allowable deviation values in micrometers. These tables depend on:
JIS B 1702-1 specifically defines the tolerances for cylindrical involute gears. It applies to both external and internal gears with straight, helical, or herringbone teeth.
The primary purpose of this standard is to ensure the interchangeability of gears and to guarantee that they meet the necessary quality levels for smooth operation, load capacity, and noise reduction. It establishes a system to classify gear accuracy into grades, allowing designers to specify the exact level of quality required for a specific application—from high-precision robotics to general industrial machinery.
Once you acquire the official PDF, do not read it cover to cover. Skip to these critical tables:
JIS B 1702-1 is a Japanese Industrial Standard specifying terminology, classifications, and requirements for protective gloves for industrial use — part 1 covers general definitions and basic requirements that apply across glove types used in industry.
