-1,Module (m)
Both the axial module of the worm and the end-face module of the worm gear are standard values.
-3,Worm Diameter Coefficient (q)
2, Transmission Ratio (i)
• Formula: i = z2/z1 (When the worm serves as the driving component).
• Recommended standard transmission ratios: 5, 7.5, 10, 12.5, 15, 20, 25, 30, 40, 50, 60, 70, 80.
3,Geometric Dimension Calculation
Pitch Circle Diameter o For the worm: d1 = q⋅m; for the worm gear: d2 = m⋅z2.
4, Meshing Conditions
-1,Correct Meshing Conditions o The axial tooth pitch of the worm is equal to the tooth pitch of the worm gear's pitch circle. o When the crossed angle is 90°, the lead angle of the worm is equal to the helix angle of the worm gear and they have the same direction of rotation.
5, Precautions for Parameter Selection
- Number of Worm Threads and Transmission Efficiency o A small number of threads (such as a single thread) can achieve a large transmission ratio and self-locking, but the efficiency is low; a larger number of threads leads to higher efficiency but greater processing difficulty.
- Limitations on the Number of Worm Gear Teeth o Avoid too few teeth causing undercutting or too many teeth resulting in insufficient stiffness.
- Lead Angle and Self-locking o Self-locking can be achieved when the lead angle is less than 3.5°.