Precision grade JIS grade
N9 (JIS B1702-1: 1998) JIS grade 5 (JIS B1702:
section of gear Aluminum-Bronze Screw Gears Normal plane
Gear teeth Standard complete depth
pressure angle 20°
Helix angle 45°
① When mating screw gears produced from the same material they may trigger abrasion and scoring. It is recommended to mate Screw Gears composed of different materials.
② The allowable torques confirmed in the table are the calculated values based on the assumed utilization conditions.
③ The backlash values demonstrated in the table will be the theoretical values for the backlash in the standard direction of a set ofidentical gears in mesh.
④ For offset shaft applications, match a RH with a RH, or LH with a LH, to make a group of screw gears. For parallel shaft applications, mesh reverse hands (RH and LH) of helical gear sets.
⑤ If the bore diameter can be less than φ 4, then your bore tolerance class is certainly H8. If the bore diameter is certainly φ 5 or φ 6, and the hole length (total duration) exceeds 3 times the diameter, then the class is also H8.