Gear Transmission Applications
The loads imposed on gears in gear transmissions vary according to the type of gears used. In the simplest case of spur gears, the load is calculated as follows:
M = 9 550 000 H / n (N· m)
P k = M / r
S k = P k tan ø
where
| M : |
Torque applied to gear (N·mm) |
| P k : |
Tangential force on gear (N) |
| S k : |
Radial force on gear (N) |
| K c : |
Combined force imposed on gear (N) |
| H : |
Power transmitted (kW) |
| n : |
Speed (rpm) |
| r : |
Pitch circle radius of drive gear (mm) |
| ø: |
Pressure angle |
In addition to the theoretical load calculated above, vibration and shock (which depend on how accurately the gear is finished) should be included using the gear factor f g by multiplying the theoretically calculated load by this factor. The values of f g should generally be those in the table. When vibration from other sources accompanies gear operation, the actual load is obtained by multiplying the load factor by this gear factor.
| Values of Gear Factor f g |
| Gear finish accuracy |
f g |
| Precision ground gears |
1 ~ 1.1 |
| Ordinary machined gears |
1.1 ~ 1.3 |
