Precision grade JIS grade N9 (JIS B1702-1: 1998) JIS grade 5 (JIS B1702: 1976)
section of gear Normal plane
Gear teeth Standard full depth
pressure angle 20°
Helix angle 45°
① When mating screw gears manufactured from the same material they may Aluminum-Bronze Screw Gears trigger abrasion and scoring. It is suggested to mate Screw Gears made up of different materials.
② The allowable torques proven in the table are the calculated values according to the assumed usage conditions.
③ The backlash values demonstrated in the table will be the theoretical ideals for the backlash in the normal 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 create a group of screw gears. For parallel shaft applications,
mesh reverse hands (RH and LH) of helical equipment sets.
⑤ If the bore diameter is certainly less than φ 4, then your bore tolerance class is definitely H8. If the bore diameter is definitely φ 5 or φ 6, and the hole length (total size) exceeds 3 times the diameter, then the class is also H8.