Overview: This document outlines the specifications and guidelines for selecting and using KHK stock helical gears, detailing catalog numbers, material types, gear characteristics, and application hints.

Catalog Numbering: KHK gears are identified by a catalog number format that includes material type, gear type, module, number of teeth, and helix direction.

Types of Helical Gears: The document describes two main types of KHK helical gears: KHG (Ground Helical Gears) and SH (Helical Gears). KHG gears use a transverse module style, while SH gears use a normal module style, and they are not interchangeable.

Material and Heat Treatment: KHG gears are made from SCM440 material and undergo thermal refining and induction hardening, whereas SH gears are made from S45C material.

Gear Characteristics: KHK helical gears are noted for their quiet operation, compact size, and cost-effectiveness, suitable for high-speed rotation applications.

Selection and Usage: Users must specify the helix direction when ordering. The document includes a mating gear selection chart and cautions for selecting gears based on strength and application conditions.

Technical Information: Detailed technical information is provided on allowable bending strength, surface durability, and calculation assumptions based on JGMA standards.

Application Hints: Guidelines for performing secondary operations, such as reboring and heat treatment, are provided to ensure safe and effective gear use.

Specifications: Detailed specifications for various gear models, including module, number of teeth, helix direction, and dimensions, are presented in tabular form.

Important Considerations: The document emphasizes understanding product tables, caution notes, and the need for precise assembly to avoid issues like noise and vibration.

Specifications: Detailed specifications for ground and steel helical gears include precision grades, material (S45C), and tooth hardness (less than 194HB). Gears are categorized by module and number of teeth, with specific dimensions for bore, hub diameter, pitch diameter, outside diameter, face width, hub width, and total length.

Allowable Torque and Backlash: Tables show allowable torque in N・m and kgf・m, along with backlash measurements in mm, based on assumed usage conditions.

Product Characteristics: The document notes that allowable torques are calculated values and backlash values are theoretical. It also mentions axial thrust forces and that right-handed and left-handed helical gears in the same module are designed to mesh as a pair, but SH gears are not interchangeable with KHG type helical gears.

Caution on Secondary Operations: Secondary operations should be performed cautiously, as gear teeth are induction hardened, preventing operations on tooth areas. Cutting off the entire hub may cause deformation due to residual stress.

Additional Notes: The document references additional sections for more detailed information on helical gears and secondary operations, indicating specific pages in a technical reference.